WorldWideScience

Sample records for thermal electric generation

  1. Solar energy thermally powered electrical generating system

    Science.gov (United States)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  2. Electricity pricing model in thermal generating stations under deregulation

    International Nuclear Information System (INIS)

    Reji, P.; Ashok, S.; Moideenkutty, K.M.

    2007-01-01

    In regulated public utilities with competitive power markets, deregulation has replaced the monopoly. Under the deregulated power market, the electricity price primarily depends on market mechanism and power demand. In this market, generators generally follow marginal pricing. Each generator fixes the electricity price based on their pricing strategy and it leads to more price volatility. This paper proposed a model to determine the electricity price considering all operational constraints of the plant and economic variables that influenced the price, for a thermal generating station under deregulation. The purpose of the model was to assist existing stations, investors in the power sector, regulatory authorities, transmission utilities, and new power generators in decision-making. The model could accommodate price volatility in the market and was based on performance incentive/penalty considering plant load factor, availability of the plant and peak/ off peak demand. The model was applied as a case study to a typical thermal utility in India to determine the electricity price. It was concluded that the case study of a thermal generating station in a deregulated environment showed that the electricity price mainly depended on the gross calorific value (GCV) of fuel, mode of operation, price of the fuel, and operating charges. 11 refs., 2 tabs., 1 fig

  3. Dispersed solar thermal generation employing parabolic dish-electric transport with field modulated generator systems

    Science.gov (United States)

    Ramakumar, R.; Bahrami, K.

    1981-01-01

    This paper discusses the application of field modulated generator systems (FMGS) to dispersed solar-thermal-electric generation from a parabolic dish field with electric transport. Each solar generation unit is rated at 15 kWe and the power generated by an array of such units is electrically collected for insertion into an existing utility grid. Such an approach appears to be most suitable when the heat engine rotational speeds are high (greater than 6000 r/min) and, in particular, if they are operated in the variable speed mode and if utility-grade a.c. is required for direct insertion into the grid without an intermediate electric energy storage and reconversion system. Predictions of overall efficiencies based on conservative efficiency figures for the FMGS are in the range of 25 per cent and should be encouraging to those involved in the development of cost-effective dispersed solar thermal power systems.

  4. Solar thermal electricity generation

    Science.gov (United States)

    Gasemagha, Khairy Ramadan

    1993-01-01

    This report presents the results of modeling the thermal performance and economic feasibility of large (utility scale) and small solar thermal power plants for electricity generation. A number of solar concepts for power systems applications have been investigated. Each concept has been analyzed over a range of plant power ratings from 1 MW(sub e) to 300 MW(sub e) and over a range of capacity factors from a no-storage case (capacity factor of about 0.25 to 0.30) up to intermediate load capacity factors in the range of 0.46 to 0.60. The solar plant's economic viability is investigated by examining the effect of various parameters on the plant costs (both capital and O & M) and the levelized energy costs (LEC). The cost components are reported in six categories: collectors, energy transport, energy storage, energy conversion, balance of plant, and indirect/contingency costs. Concentrator and receiver costs are included in the collector category. Thermal and electric energy transport costs are included in the energy transport category. Costs for the thermal or electric storage are included in the energy storage category; energy conversion costs are included in the energy conversion category. The balance of plant cost category comprises the structures, land, service facilities, power conditioning, instrumentation and controls, and spare part costs. The indirect/contingency category consists of the indirect construction and the contingency costs. The concepts included in the study are (1) molten salt cavity central receiver with salt storage (PFCR/R-C-Salt); (2) molten salt external central receiver with salt storage (PFCR/R-E-Salt); (3) sodium external central receiver with sodium storage (PFCR/RE-Na); (4) sodium external central receiver with salt storage (PFCR/R-E-Na/Salt); (5) water/steam external central receiver with oil/rock storage (PFCR/R-E-W/S); (6) parabolic dish with stirling engine conversion and lead acid battery storage (PFDR/SLAB); (7) parabolic dish

  5. Solar thermal electric power generation - an attractive option for Pakistan

    International Nuclear Information System (INIS)

    Khan, N.A

    1999-01-01

    Solar Thermal Energy is being successfully used for production of electricity in few developed countries for more than 10 years. In solar Electric Generating Systems high temperature is generated by concentrating solar energy on black absorber pipe in evacuated glass tubes. This heat is absorbed and transported with the help of high temperature oil in to highly insulated heat exchanger storage tanks. They are subsequently used to produce steam that generates power through steam turbines as in standard thermal power plants. Various components involved in Solar thermal field have been developed at the Solar Systems Laboratory of College of EME, NUST Rawalpindi. It is considered as a cost effective alternate for power generation. The research has been partially sponsored by Ministry of Science and Technology under its Public Sector Development Program (PSDP) in (1996-1998). Parabolic mirror design, fabrication, polishing, installation, solar tracking, absorber pipe, glass tubes, steam generation al have been developed. This paper will cover the details of indigenous technological break through made in this direction. (author)

  6. Full-energy-chain analysis of greenhouse gas emissions for solar thermal electric power generation systems

    International Nuclear Information System (INIS)

    Norton, B.; Lawson, W.R.

    1997-01-01

    Technical attributes and environmental impacts of solar thermal options for centralized electricity generation are discussed. In particular, the full-energy-chain, including embodied energy and energy production, is considered in relation to greenhouse gas emission arising from solar thermal electricity generation. Central receiver, parabolic dish, parabolic trough and solar pond systems are considered. (author)

  7. Ocean thermal gradient as a generator of electricity. OTEC power plant

    Science.gov (United States)

    Enrique, Luna-Gomez Victor; Angel, Alatorre-Mendieta Miguel

    2016-04-01

    The OTEC (Ocean Thermal Energy Conversion) is a power plant that uses the thermal gradient of the sea water between the surface and a depth of about 700 meters. It works by supplying the heat to a steam machine, for evaporation, with sea water from the surface and cold, to condense the steam, with deep sea water. The energy generated by the power plant OTEC can be transferred to the electric power grid, another use is to desalinate seawater. During the twentieth century in some countries experimental power plants to produce electricity or obtaining drinking water they were installed. On the Mexico's coast itself this thermal gradient, as it is located in tropical seas it occurs, so it has possibilities of installing OTEC power plant type. In this paper one type OTEC power plant operation is represented in most of its components.

  8. Low-cost distributed solar-thermal-electric power generation

    Science.gov (United States)

    Der Minassians, Artin; Aschenbach, Konrad H.; Sanders, Seth R.

    2004-01-01

    Due to their high relative cost, solar electric energy systems have yet to be exploited on a widespread basis. It is believed in the energy community that a technology similar to photovoltaic (PV), but offered at about $1/W would lead to widespread deployment at residential and commercial sites. This paper addresses the investigation and feasibility study of a low-cost solar thermal electricity generation technology, suitable for distributed deployment. Specifically, we discuss a system based on nonimaging solar concentrators, integrated with free-piston Stirling engine devices incorporating integrated electric generation. We target concentrator-collector operation at moderate temperatures, in the range of 125°C to 150°C. This temperature is consistent with use of optical concentrators with concentration ratios on the order of 1-2. These low ratio concentrators admit wide angles of radiation acceptance and are thus compatible with no diurnal tracking, and no or only a few seasonal adjustments. Thus, costs and reliability hazards associated with tracking hardware systems are avoided. Further, we note that in the intended application, there is no shortage of incident solar energy, but rather it is the capital cost of the solar-electric system that is most precious. Thus, we outline a strategy for exploiting solar resources in a cost constrained manner. The paper outlines design issues, and a specific design for an appropriately dimensioned free-piston Stirling engine. Only standard low-cost materials and manufacturing methods are required to realize such a machine.

  9. Inspection maintenance and planning of shutdown in thermal electric generating plants

    International Nuclear Information System (INIS)

    Dezordi, W.L.; Correa, D.A.; Kina, M.

    1984-01-01

    The schedule shutdown of an industrial plant and, more specifically, of an electrical generating station, is becoming increasingly important. The major parameters to be taken into account for the planning of such a shutdown are basically of economic-financial nature such as costs of the related services (materials, equipment, manpower, etc), loss of revenue caused by the station's shutdown as well as by the station availability, and other requirements expected from it by the Load Dispatch and consumers. Improving the equipment's performances and the station's availability are the fundamental objectives to be strived for. The authors present in this paper, in an abridged form, the planning tools used for thermal electric generating plants shutdowns for inspections, maintenance and design changes implementation. (Author) [pt

  10. Economic aspects of Solar Thermal Technologies for electricity generation

    International Nuclear Information System (INIS)

    Meinecke, W.

    1993-01-01

    Economic results of German studies are presented, which compare the four solar thermal technologies for electricity generation (parabolic trough collector system, central receiver system, parabolic dish/Stirling system, solar chimney plant). These studies were carried out by Interatom (today Siemens/KWU) in Bergisch Gladbach, Flachglas Solartechnik in Koln and Schlaich Bergermann and Partner in Stuggart under contract of DLR in Koln. Funds were made available by the German Ministry of Research and Development (BMFT). The results indicate that all of the investigated technologies have the potential to reduce the generating costs and that in the future costs of below 0.30 DM/kWh could be expected under excellent insolation conditions (e.G. 2850 kWh/m''2 a direct insolation as in California/USA). (Author) 25 refs

  11. Natural gas and electricity generation in Queensland

    International Nuclear Information System (INIS)

    Webb, G.

    2001-01-01

    The focus of this article is on electricity generation in Queensland. Black coal accounted for 97 percent, while natural gas made up only 1 percent of the fuel used in thermal power generation in 1997-98. The share of natural gas in thermal electricity generation is expected to rise to 21 percent by 2014-2015, because of the emphasis on natural gas in Queensland's new energy policy. Since 1973-1974, Queensland has led the way in electricity consumption, with an average annual growth rate of 6.8 percent but the average thermal efficiency has fallen from 38.0 percent in 1991-1992, to 36.6 percent in 1997-1998

  12. Investigation of Solar Hybrid Electric/Thermal System with Radiation Concentrator and Thermoelectric Generator

    Directory of Open Access Journals (Sweden)

    Edgar Arturo Chávez Urbiola

    2013-01-01

    Full Text Available An experimental study of a solar-concentrating system based on thermoelectric generators (TEGs was performed. The system included an electrical generating unit with 6 serially connected TEGs using a traditional semiconductor material, Bi2Te3, which was illuminated by concentrated solar radiation on one side and cooled by running water on the other side. A sun-tracking concentrator with a mosaic set of mirrors was used; its orientation towards the sun was achieved with two pairs of radiation sensors, a differential amplifier, and two servomotors. The hot side of the TEGs at midday has a temperature of around 200°C, and the cold side is approximately 50°C. The thermosiphon cooling system was designed to absorb the heat passing through the TEGs and provide optimal working conditions. The system generates 20 W of electrical energy and 200 W of thermal energy stored in water with a temperature of around 50°C. The hybrid system studied can be considered as an alternative to photovoltaic/thermal systems, especially in countries with abundant solar radiation, such as Mexico, China, and India.

  13. Gas in electricity generation [In New Zealand

    International Nuclear Information System (INIS)

    Devine, K.

    1995-01-01

    Gas is New Zealand's major thermal fuel for electricity generation. This paper describes what influences the volumes of gas burnt by ECNZ, and forecasts future gas demands for electricity generation. It also reviews the uncertainties associated with these forecasts and likely competition in building new electricity generating stations and outlines the strategy now being formulated to accommodate them. Because ECNZ's generation system is hydro-based, relatively small rapid changes in hydrological conditions can significantly affect the amount of gas used. This situation will change over time with major increases in thermal generation likely to be needed over the next 20 years. However, there are considerable uncertainties on gas supply and electricity demand levels in the long run, which will complicate investment and fuel decisions. (Author)

  14. Electric power generator

    International Nuclear Information System (INIS)

    Carney, H.C.

    1977-01-01

    An electric power generator of the type employing a nuclear heat source and a thermoelectric converter is described wherein a transparent thermal insulating medium is provided inside an encapsulating enclosure to thermally insulate the heat source and thermoelectric generator. The heat source, the thermoelectric converter, and the enclosure are provided with facing surfaces which are heat-reflective to a substantial degree to inhibit radiation of heat through the medium of the encapsulating enclosure. Multiple reflective foils may be spaced within the medium as necessary to inhibit natural convection of heat and/or further inhibit radiation

  15. Electric Motor-Generator for a Hybrid Electric Vehicle

    OpenAIRE

    Odvářka, Erik; Mebarki, Abdeslam; Gerada, David; Brown, Neil; Ondrůšek, Čestmír

    2009-01-01

    Several topologies of electrical machines can be used to meet requirements for application in a hybrid electric vehicle. This paper describes process of an electric motor-generator selection, considering electromagnetic, thermal and basic control design. The requested electrical machine must develop 45 kW in continuous operation at 1300 rpm with field weakening capability up to 2500 rpm. Both radial and axial flux topologies are considered as potential candidates. A family of axial flux machi...

  16. On the possibility of generation of cold and additional electric energy at thermal power stations

    Science.gov (United States)

    Klimenko, A. V.; Agababov, V. S.; Borisova, P. N.

    2017-06-01

    A layout of a cogeneration plant for centralized supply of the users with electricity and cold (ECCG plant) is presented. The basic components of the plant are an expander-generator unit (EGU) and a vapor-compression thermotransformer (VCTT). At the natural-gas-pressure-reducing stations, viz., gas-distribution stations and gas-control units, the plant is connected in parallel to a throttler and replaces the latter completely or partially. The plant operates using only the energy of the natural gas flow without burning the gas; therefore, it can be classified as a fuelless installation. The authors compare the thermodynamic efficiencies of a centralized cold supply system based on the proposed plant integrated into the thermal power station scheme and a decentralized cold supply system in which the cold is generated by electrically driven vapor-compression thermotransformers installed on the user's premises. To perform comparative analysis, the exergy efficiency was taken as the criterion since in one of the systems under investigation the electricity and the cold are generated, which are energies of different kinds. It is shown that the thermodynamic efficiency of the power supply using the proposed plant proves to be higher within the entire range of the parameters under consideration. The article presents the results of investigating the impact of the gas heating temperature upstream from the expander on the electric power of the plant, its total cooling capacity, and the cooling capacities of the heat exchangers installed downstream from the EGU and the evaporator of the VCTT. The results of calculations are discussed that show that the cold generated at the gas-control unit of a powerful thermal power station can be used for the centralized supply of the cold to the ventilation and conditioning systems of both the buildings of the power station and the neighboring dwelling houses, schools, and public facilities during the summer season.

  17. Impacts of propagating, frustrated and surface modes on radiative, electrical and thermal losses in nanoscale-gap thermophotovoltaic power generators

    Science.gov (United States)

    Bernardi, Michael P.; Dupré, Olivier; Blandre, Etienne; Chapuis, Pierre-Olivier; Vaillon, Rodolphe; Francoeur, Mathieu

    2015-01-01

    The impacts of radiative, electrical and thermal losses on the performances of nanoscale-gap thermophotovoltaic (nano-TPV) power generators consisting of a gallium antimonide cell paired with a broadband tungsten and a radiatively-optimized Drude radiator are analyzed. Results reveal that surface mode mediated nano-TPV power generation with the Drude radiator outperforms the tungsten radiator, dominated by frustrated modes, only for a vacuum gap thickness of 10 nm and if both electrical and thermal losses are neglected. The key limiting factors for the Drude- and tungsten-based devices are respectively the recombination of electron-hole pairs at the cell surface and thermalization of radiation with energy larger than the cell absorption bandgap. A design guideline is also proposed where a high energy cutoff above which radiation has a net negative effect on nano-TPV power output due to thermal losses is determined. It is shown that the power output of a tungsten-based device increases by 6.5% while the cell temperature decreases by 30 K when applying a high energy cutoff at 1.45 eV. This work demonstrates that design and optimization of nano-TPV devices must account for radiative, electrical and thermal losses. PMID:26112658

  18. Thermal electric effects and heat generation in polypyrrole coated PET fabrics

    OpenAIRE

    Avloni, J.; Florio, L.; Henn, A. R.; Sparavigna, A.

    2007-01-01

    Polypyrrole chemically synthesized on PET gives rise to textiles with a high electric conductivity, suitable for several applications from antistatics to electromagnetic interference shielding devices. Here, we discuss investigations on thermal electric performances of the polypyrrole coated PET in a wide range of temperatures above room temperature. The Seebeck coefficient turns out to be comparable with that of metal thermocouple materials. Since polypyrrole shows extremely low thermal diff...

  19. Electric power generation the changing dimensions

    CERN Document Server

    Tagare, D M

    2011-01-01

    "This book offers an analytical overview of established electric generation processes, along with the present status & improvements for meeting the strains of reconstruction. These old methods are hydro-electric, thermal & nuclear power production. The book covers climatic constraints; their affects and how they are shaping thermal production. The book also covers the main renewable energy sources, wind and PV cells and the hybrids arising out of these. It covers distributed generation which already has a large presence is now being joined by wind & PV energies. It covers their accommodation in the present system. It introduces energy stores for electricity; when they burst upon the scene in full strength are expected to revolutionize electricity production. In all the subjects covered, there are references to power marketing & how it is shaping production. There will also be a reference chapter on how the power market works"--Provided by publisher.

  20. Feasibility study of Thermal Electric Generator Configurations as Renewable Energy Sources

    Science.gov (United States)

    Akmal Johar, Muhammad; Yahaya, Zulkarnain; Faizan Marwah, Omar Mohd; Jamaludin, Wan Akashah Wan; Najib Ribuan, Mohamed

    2017-10-01

    Thermoelectric Generator is a solid state device that able to convert thermal energy into electrical energy via temperature differences. The technology is based on Seebeck effect that was discovered in year 1821, however till now there is no real application to exploit this capability in mass scale. This research will report the performance analysis of TEG module in controlled environment of lab scale model. National Instrument equipment and Labview software has been choosen and developed to measure the TEG module in various configurations. Based on the experiment result, an additional passive cooling effort has produced a better ΔT by 7°C. The optimal electrical loading of single TEG is recorded at 200Ω. As for circuit connections, series connection has shown superior power output when compared to parallel connection or single TEG. A series connection of two TEGs has produced power output of 416.82μW when compared to other type connections that only produced around 100μW.

  1. Electrical power systems for distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, T.A.; Huval, S.J. [Stewart & Stevenson Services, Inc., Houston, TX (United States)

    1996-12-31

    {open_quotes}Distributed Generation{close_quotes} has become the {open_quotes}buzz{close_quotes} word of an electric utility industry facing deregulation. Many industrial facilities utilize equipment in distributed installations to serve the needs of a thermal host through the capture of exhaust energy in a heat recovery steam generator. The electrical power generated is then sold as a {open_quotes}side benefit{close_quotes} to the cost-effective supply of high quality thermal energy. Distributed generation is desirable for many different reasons, each with unique characteristics of the product. Many years of experience in the distributed generation market has helped Stewart & Stevenson to define a range of product features that are crucial to most any application. The following paper will highlight a few of these applications. The paper will also examine the range of products currently available and in development. Finally, we will survey the additional services offered by Stewart & Stevenson to meet the needs of a rapidly changing power generation industry.

  2. Performance results of a solar greenhouse combining electrical and thermal energy production

    NARCIS (Netherlands)

    Sonneveld, P.J.; Swinkels, G.L.A.M.; Campen, J.B.; Tuijl, van B.A.J.; Janssen, H.J.J.; Bot, G.P.A.

    2010-01-01

    Performance results are given of a new type of greenhouse, which combines reflection of near infrared radiation (NIR) with electrical power generation using hybrid photovoltaic cell/thermal collector modules. Besides the generation of electrical and thermal energy, the reflection of the NIR will

  3. Prospects for solar thermal electricity generation - an introduction

    International Nuclear Information System (INIS)

    DeLaquil, P.

    1991-01-01

    The future potential for solar thermal electric power plants is quite significant. The size of the renewable energy resource base for the United States of America alone is almost 500 times its current primary energy consumption. Unfortunately, the levels of current utilization are quite small. Why have these technologies not made a larger contribution to today's market? The answer is that significant barriers still exist. (orig.)

  4. Solar thermal aided power generation

    International Nuclear Information System (INIS)

    Hu, Eric; Yang, YongPing; Nishimura, Akira; Yilmaz, Ferdi; Kouzani, Abbas

    2010-01-01

    Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO 2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature. Solar thermal is another way to use solar energy to generate power. Many attempts to establish solar (solo) thermal power stations have been practiced all over the world. Although there are some advantages in solo solar thermal power systems, the efficiencies and costs of these systems are not so attractive. Alternately by modifying, if possible, the existing coal-fired power stations to generate green sustainable power, a much more efficient means of power generation can be reached. This paper presents the concept of solar aided power generation in conventional coal-fired power stations, i.e., integrating solar (thermal) energy into conventional fossil fuelled power generation cycles (termed as solar aided thermal power). The solar aided power generation (SAPG) concept has technically been derived to use the strong points of the two technologies (traditional regenerative Rankine cycle with relatively higher efficiency and solar heating at relatively low temperature range). The SAPG does not only contribute to increase the efficiencies of the conventional power station and reduce its emission of the greenhouse gases, but also provides a better way to use solar heat to generate the power. This paper presents the advantages of the SAPG at conceptual level.

  5. High-performance flat-panel solar thermoelectric generators with high thermal concentration

    Science.gov (United States)

    Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J. Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

    2011-07-01

    The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m-2) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity.

  6. High-performance flat-panel solar thermoelectric generators with high thermal concentration.

    Science.gov (United States)

    Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

    2011-05-01

    The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m(-2)) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity. © 2011 Macmillan Publishers Limited. All rights reserved

  7. Experimental investigation on thermal management of electric vehicle battery with heat pipe

    International Nuclear Information System (INIS)

    Rao Zhonghao; Wang Shuangfeng; Wu Maochun; Lin Zirong; Li Fuhuo

    2013-01-01

    Highlights: ► The thermal management system of electric vehicle battery with heat pipes was designed. ► Temperature rise is a key factor for the design of power battery thermal management system. ► Temperature distribution is inevitable to reference for better design of heat pipes used for heat dissipation. ► Heat pipes are effective for power batteries thermal management within electric vehicles. - Abstract: In order to increase the cycle time of power batteries and decrease the overall cost of electric vehicles, the thermal management system equipped with heat pipes was designed according to the heat generated character of power batteries. The experimental result showed that the maximum temperature could be controlled below 50 °C when the heat generation rate was lower than 50 W. Coupled with the desired temperature difference, the heat generation rate should not exceed 30 W. The maximum temperature and temperature difference are kept within desired rang under unsteady operating conditions and cycle testing conditions. Applying heat pipes based power batteries thermal management is an effective method for energy saving in electric vehicles.

  8. Optimization of low temperature solar thermal electric generation with Organic Rankine Cycle in different areas

    International Nuclear Information System (INIS)

    Jing, Li; Gang, Pei; Jie, Ji

    2010-01-01

    The presented low temperature solar thermal electric generation system mainly consists of compound parabolic concentrators (CPC) and the Organic Rankine Cycle (ORC) working with HCFC-123. A novel design is proposed to reduce heat transfer irreversibility between conduction oil and HCFC-123 in the heat exchangers while maintaining the stability of electricity output. Mathematical formulations are developed to study the heat transfer and energy conversion processes and the numerical simulation is carried out based on distributed parameters. Annual performances of the proposed system in different areas of Canberra, Singapore, Bombay, Lhasa, Sacramento and Berlin are simulated. The influences of the collector tilt angle adjustment, the connection between the heat exchangers and the CPC collectors, and the ORC evaporation temperature on the system performance are investigated. The results indicate that the three factors have a major impact on the annual electricity output and should be the key points of optimization. And the optimized system shows that: (1) The annual received direct irradiance can be significantly increased by two or three times optimal adjustments even when the CPC concentration ratio is smaller than 3.0. (2) Compared with the traditional single-stage collectors, two-stage collectors connected with the heat exchangers by two thermal oil cycles can improve the collector efficiency by 8.1-20.9% in the simultaneous processes of heat collection and power generation. (3) On the use of the market available collectors the optimal ORC evaporation temperatures in most of the simulated areas are around 120 C. (author)

  9. Economic impact of latent heat thermal energy storage systems within direct steam generating solar thermal power plants with parabolic troughs

    International Nuclear Information System (INIS)

    Seitz, M.; Johnson, M.; Hübner, S.

    2017-01-01

    Highlights: • Integration of a latent heat thermal energy storage system into a solar direct steam generation power cycle. • Parametric study of solar field and storage size for determination of the optimal layout. • Evaluation of storage impact on the economic performance of the solar thermal power plant. • Economic comparison of new direct steam generation plant layout with state-of-the-art oil plant layout. - Abstract: One possible way to further reduce levelized costs of electricity of concentrated solar thermal energy is to directly use water/steam as the primary heat transfer fluid within a concentrated collector field. This so-called direct steam generation offers the opportunity of higher operating temperatures and better exergy efficiency. A technical challenge of the direct steam generation technology compared to oil-driven power cycles is a competitive storage technology for heat transfer fluids with a phase change. Latent heat thermal energy storages are suitable for storing heat at a constant temperature and can be used for direct steam generation power plants. The calculation of the economic impact of an economically optimized thermal energy storage system, based on a latent heat thermal energy storage system with phase change material, is the main focus of the presented work. To reach that goal, a thermal energy storage system for a direct steam generation power plant with parabolic troughs in the solar field was thermally designed to determine the boundary conditions. This paper discusses the economic impact of the designed thermal energy storage system based on the levelized costs of electricity results, provided via a wide parametric study. A state-of-the-art power cycle with a primary and a secondary heat transfer fluid and a two-tank thermal energy storage is used as a benchmark technology for electricity generation with solar thermal energy. The benchmark and direct steam generation systems are compared to each other, based respectively

  10. Thermoacoustic magnetohydrodynamic electrical generator

    International Nuclear Information System (INIS)

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1986-01-01

    A thermoacoustic magnetohydrodynamic electrical generator is described comprising a magnet having a magnetic field, an elongate hollow housing containing an electrically conductive liquid and a thermoacoustic structure positioned in the liquid, heat exchange means thermally connected to the thermoacoustic structure for inducing the liquid to oscillate at an acoustic resonant frequency within the housing. The housing is positioned in the magnetic field and oriented such that the direction of the magnetic field and the direction of oscillatory motion of the liquid are substantially orthogonal to one another, first and second electrical conductor means connected to the liquid on opposite sides of the housing along an axis which is substantially orthogonal to both the direction of the magnetic field and the direction of oscillatory motion of the liquid, an alternating current output signal is generated in the conductor means at a frequency corresponding to the frequency of the oscillatory motion of the liquid

  11. Distributed generation incorporated with the thermal generation for optimum operation of a smart grid considering forecast error

    International Nuclear Information System (INIS)

    Howlader, Harun Or Rashid; Matayoshi, Hidehito; Senjyu, Tomonobu

    2015-01-01

    Highlights: • Optimal operation of the thermal generation for the smart grid system. • Different distributed generations are considered as the power generation sources. • Forecast error of the renewable energy systems is considered. • Controllable loads of the smart houses are considered to achieve the optimal operation. • Economical benefits can be achieved for the smart grid system. - Abstract: This paper concentrates on the optimal operation of the conventional thermal generators with distributed generations for a smart grid considering forecast error. The distributed generations are considered as wind generators, photovoltaic generators, battery energy storage systems in the supply side and a large number of smart houses in the demand side. A smart house consists of the electric vehicle, heat pump, photovoltaic generator and solar collector. The electric vehicle and heat pump are considered as the controllable loads which can compensate the power for the forecast error of renewable energy sources. As a result, power generation cost of the smart grid can reduce through coordinated with distributed generations and thermal units scheduling process. The electric vehicles of the smart house are considered as the spinning reserve in the scheduling process which lead to lessen the additional operation of thermal units. Finally, obtained results of the proposed system have been compared with the conventional method. The conventional method does not consider the electric vehicle in the smart houses. The acquired results demonstrate that total power generation cost of the smart grid has been reduced by the proposed method considering forecast error. Effectiveness of the proposed method has been verified by the extensive simulation results using MATLAB® software

  12. Electrically Driven Thermal Management: Flight Validation, Experiment Development, Future Technologies

    Science.gov (United States)

    Didion, Jeffrey R.

    2018-01-01

    Electrically Driven Thermal Management is an active research and technology development initiative incorporating ISS technology flight demonstrations (STP-H5), development of Microgravity Science Glovebox (MSG) flight experiment, and laboratory-based investigations of electrically based thermal management techniques. The program targets integrated thermal management for future generations of RF electronics and power electronic devices. This presentation reviews four program elements: i.) results from the Electrohydrodynamic (EHD) Long Term Flight Demonstration launched in February 2017 ii.) development of the Electrically Driven Liquid Film Boiling Experiment iii.) two University based research efforts iv.) development of Oscillating Heat Pipe evaluation at Goddard Space Flight Center.

  13. Development of a 3 kW double-acting thermoacoustic Stirling electric generator

    International Nuclear Information System (INIS)

    Wu, Zhanghua; Yu, Guoyao; Zhang, Limin; Dai, Wei; Luo, Ercang

    2014-01-01

    Highlights: • A 3 kW double-acting thermoacoustic Stirling electric generator is introduced. • 1.57 kW electric power with 16.8% thermal-to-electric efficiency was achieved. • High mechanical damping coefficient greatly decreases the system performance. • Performance difference is significant, which also decreased system performance. - Abstract: In this paper, a double-acting thermoacoustic Stirling electric generator is proposed as a new device capable of converting external heat into electric power. In the system, at least three thermoacoustic Stirling heat engines and three linear alternators are used to build a multiple-cylinder electricity generator. In comparison with the conventional thermoacoustic electricity generation system, the double-acting thermoacoustic Stirling electric generator has advantages on efficiency, power density and power capacity. In order to verify the idea, a prototype of 3 kW three-cylinder double-acting thermoacoustic Stirling electric generator is designed, built and tested. Based on the classic thermoacoustic theory, numerical simulation is performed to obtain the thermodynamic parameters of the engine. And distributions of key parameters are presented for a better understanding of the energy conversion process in the engine. In the experiments, a maximum electric power of about 1.57 kW and a maximum thermal-to-electric conversion efficiency of 16.8% were achieved with 5 MPa pressurized helium and 86 Hz working frequency. However, we find that the mechanical damping coefficient of the piston is dramatically increased due to the deformation of the cylinder wall caused by high thermal stress during the experiments. Thereby, the system performance was greatly reduced. Additionally, the performance differences between three engines and three alternators are significant, such as the heating temperature difference between three heater blocks of the engines, the piston displacement and the output electric power differences between

  14. Stirling engines for low-temperature solar-thermal-electric power generation

    Science.gov (United States)

    der Minassians, Artin

    This dissertation discusses the design and development of a distributed solar-thermal-electric power generation system that combines solar-thermal technology with a moderate-temperature Stirling engine to generate electricity. The conceived system incorporates low-cost materials and utilizes simple manufacturing processes. This technology is expected to achieve manufacturing cost of less than $1/W. Since solar-thermal technology is mature, the analysis, design, and experimental assessment of moderate-temperature Stirling engines is the main focus of this thesis. The design, fabrication, and test of a single-phase free-piston Stirling engine prototype is discussed. This low-power prototype is designed and fabricated as a test rig to provide a clear understanding of the Stirling cycle operation, to identify the key components and the major causes of irreversibility, and to verify corresponding theoretical models. As a component, the design of a very low-loss resonant displacer piston subsystem is discussed. The displacer piston is part of a magnetic circuit that provides both a required stiffness and actuation forces. The stillness is provided by a magnetic spring, which incorporates an array of permanent magnets and has a very linear stiffness characteristic that facilitates the frequency tuning. In this prototype, the power piston is not mechanically linked to the displacer piston and forms a mass-spring resonating subsystem with the engine chamber gas spring and has resonant frequency matched to that of the displacer. The fabricated engine prototype is successfully tested and the experimental results are presented and discussed. Extensive experimentation on individual component subsystems confirms the theoretical models and design considerations, providing a sound basis for higher power Stirling engine designs for residential or commercial deployments. Multi-phase Stirling engine systems are also considered and analyzed. The modal analysis of these machines proves

  15. Technical assessment of discarded tires gasification as alternative technology for electricity generation.

    Science.gov (United States)

    Machin, Einara Blanco; Pedroso, Daniel Travieso; de Carvalho, João Andrade

    2017-10-01

    Concern about contamination associated with the disposal of tires has led to the search for technologies to reuse discarded tires, which include the use of Tire Derived Fuel (TDF) as fuel in advanced thermal-conversion processes, this allows the energy use of these wastes at affordable costs and reduces the environmental impact on scrap tires disposal. A theoretical assessment of the technical viability of TDF gasification for electric and thermal power generation, from the producer gas combustion in an internal combustion engine and in a gas turbine, was performed. The combustion of producer gas derived from the gasification of TDF in an internal combustion engine driving a generator (ICE-G) appears as the more efficient route for electricity generation when compared with the efficiency obtained with the use of gas turbine (GT-G). A higher global efficiency, considering the electric and thermal generation efficiency can be expected with the use of TDF producer gas in GT-G, where is expected an overall efficiency of 77.49%. The assessment shows that is possible produces up to 7.67MJ and 10.62MJ of electric and thermal energy per kilogram of TDF gasified using an ICE-G and up to 6.06MJ and 13.03MJ of electric and thermal energy respectively per kilogram of gasified TDF using a GT-G. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Solar thermal energy conversion to electrical power

    International Nuclear Information System (INIS)

    Trinh, Anh-Khoi; González, Ivan; Fournier, Luc; Pelletier, Rémi; Sandoval V, Juan C.; Lesage, Frédéric J.

    2014-01-01

    The conversion of solar energy to electricity currently relies primarily on the photovoltaic effect in which photon bombardment of photovoltaic cells drives an electromotive force within the material. Alternatively, recent studies have investigated the potential of converting solar radiation to electricity by way of the Seebeck effect in which charge carrier mobility is generated by an asymmetric thermal differential. The present study builds upon these latest advancements in the state-of-the-art of thermoelectric system management by combining solar evacuated tube technology with commercially available Bismuth Telluride semiconductor modules. The target heat source is solar radiation and the target heat sink is thermal convection into the ambient air relying on wind aided forced convection. These sources of energy are reproduced in a laboratory controlled environment in order to maintain a thermal dipole across a thermoelectric module. The apparatus is then tested in a natural environment. The novelty of the present work lies in a net thermoelectric power gain for ambient environment applications and an experimental validation of theoretical electrical characteristics relative to a varying electrical load. - Highlights: • Solar radiation maintains a thermal tension which drives an electromotive force. • Voltage, current and electric power are reported and discussed. • Theoretical optimal thermoelectric conversion predictions are presented. • Theory is validated with experimentally measured data

  17. Enhanced Efficiency of Thermoelectric Generator by Optimizing Mechanical and Electrical Structures

    Directory of Open Access Journals (Sweden)

    Jinlong Chen

    2017-09-01

    Full Text Available Much attention has been paid to the application of low temperature thermal resources, especially for power generation in recent years. Most of the current commercialized thermal (including geothermal power-generation technologies convert thermal energy to electric energy indirectly, that is, making mechanical work before producing electricity. Technology using a thermoelectric generator (TEG, however, can directly transform thermal energy into electricity through the Seebeck effect. TEG technology has many advantages such as compactness, quietness, and reliability because there are no moving parts. One of the biggest disadvantages of TEGs is the low efficiency from thermal to electric energy. For this reason, we redesigned and modified our previous 1 KW (at a temperature difference of around 120 °C TEG system. The output power of the system was improved significantly, about 34.6% greater; the instantaneous efficiency of the TEG system could reach about 6.5%. Laboratory experiments have been conducted to measure the output power at different conditions: different connection modes between TEG modules, different mechanical structures, and different temperature differences between hot and cold sides. The TEG apparatus has been tested and the data have been presented. This kind of TEG power system can be applied in many thermal and geothermal sites with low temperature resources, including oil fields where fossil and geothermal energies are coproduced.

  18. Determining an energy-optimal thermal management strategy for electric driven vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Suchaneck, Andre; Probst, Tobias; Puente Leon, Fernando [Karlsruher Institut fuer Technology (KIT), Karlsruhe (Germany). Inst. of Industrial Information Technology (IIIT)

    2012-11-01

    In electric, hybrid electric and fuel cell vehicles, thermal management may have a significant impact on vehicle range. Therefore, optimal thermal management strategies are required. In this paper a method for determining an energy-optimal control strategy for thermal power generation in electric driven vehicles is presented considering all controlled devices (pumps, valves, fans, and the like) as well as influences like ambient temperature, vehicle speed, motor and battery and cooling cycle temperatures. The method is designed to be generic to increase the thermal management development process speed and to achieve the maximal energy reduction for any electric driven vehicle (e.g., by waste heat utilization). Based on simulations of a prototype electric vehicle with an advanced cooling cycle structure, the potential of the method is shown. (orig.)

  19. Reversible temperature regulation of electrical and thermal conductivity using liquid–solid phase transitions

    Science.gov (United States)

    Zheng, Ruiting; Gao, Jinwei; Wang, Jianjian; Chen, Gang

    2011-01-01

    Reversible temperature tuning of electrical and thermal conductivities of materials is of interest for many applications, including seasonal regulation of building temperature, thermal storage and sensors. Here we introduce a general strategy to achieve large contrasts in electrical and thermal conductivities using first-order phase transitions in percolated composite materials. Internal stress generated during a phase transition modulates the electrical and thermal contact resistances, leading to large contrasts in the electrical and thermal conductivities at the phase transition temperature. With graphite/hexadecane suspensions, the electrical conductivity changes 2 orders of magnitude and the thermal conductivity varies up to 3.2 times near 18 °C. The generality of the approach is also demonstrated in other materials such as graphite/water and carbon nanotube/hexadecane suspensions. PMID:21505445

  20. Reversible temperature regulation of electrical and thermal conductivity using liquid-solid phase transitions.

    Science.gov (United States)

    Zheng, Ruiting; Gao, Jinwei; Wang, Jianjian; Chen, Gang

    2011-01-01

    Reversible temperature tuning of electrical and thermal conductivities of materials is of interest for many applications, including seasonal regulation of building temperature, thermal storage and sensors. Here we introduce a general strategy to achieve large contrasts in electrical and thermal conductivities using first-order phase transitions in percolated composite materials. Internal stress generated during a phase transition modulates the electrical and thermal contact resistances, leading to large contrasts in the electrical and thermal conductivities at the phase transition temperature. With graphite/hexadecane suspensions, the electrical conductivity changes 2 orders of magnitude and the thermal conductivity varies up to 3.2 times near 18 °C. The generality of the approach is also demonstrated in other materials such as graphite/water and carbon nanotube/hexadecane suspensions.

  1. Possibilities for retrofitting of the existing thermal electric power plants using solar power technologies

    International Nuclear Information System (INIS)

    Matjanov, Erkinjon K.; Abduganieva, Farogat A.; Aminov, Zarif Z.

    2012-01-01

    Full text: Total installed electric power output of the existing thermal electric power plants in Uzbekistan is reaches 12 GW. Thermal electric power plants, working on organic fuel, produce around 88 % of the electricity in the country. The emission coefficient of CO 2 gases is 620 gram/kwph. Average electric efficiency of the thermal electric power plants is 32.1 %. The mentioned above data certifies, that the existing thermal electric power plants of Uzbekistan are physically and morally aged and they need to be retrofitted. Retrofitting of the existing thermal electric power plants can be done by several ways such as via including gas turbine toppings, by using solar technologies, etc. Solar thermal power is a relatively new technology which has already shown its enormous promise. With few environmental impacts and a massive resource, it offers a comparable opportunity to the sunniest Uzbekistan. Solar thermal power uses direct sunlight, so it must be sited in regions with high direct solar radiation. In many regions, one square km of land is enough to generate as much as 100-120 GWh of electricity per year using the solar thermal technology. This is equivalent to the annual production of a 50 MW conventional coal or gas-fired mid-load power plant. Solar thermal power plants can be designed for solar-only or for hybrid operation. Producing electricity from the energy in the sun's rays is a straightforward process: direct solar radiation can be concentrated and collected by a range of Concentrating Solar Power technologies to provide medium- to high temperature heat. This heat is then used to operate a conventional power cycle, for example through a steam turbine or a Stirling engine. Solar heat collected during the day can also be stored in liquid or solid media such as molten salts, ceramics, concrete or, in the future, phase-changing salt mixtures. At night, it can be extracted from the storage medium thereby continuing turbine operation. Currently, the

  2. Solar thermal organic rankine cycle for micro-generation

    Science.gov (United States)

    Alkahli, N. A.; Abdullah, H.; Darus, A. N.; Jalaludin, A. F.

    2012-06-01

    The conceptual design of an Organic Rankine Cycle (ORC) driven by solar thermal energy is developed for the decentralized production of electricity of up to 50 kW. Conventional Rankine Cycle uses water as the working fluid whereas ORC uses organic compound as the working fluid and it is particularly suitable for low temperature applications. The ORC and the solar collector will be sized according to the solar flux distribution in the Republic of Yemen for the required power output of 50 kW. This will be a micro power generation system that consists of two cycles, the solar thermal cycle that harness solar energy and the power cycle, which is the ORC that generates electricity. As for the solar thermal cycle, heat transfer fluid (HTF) circulates the cycle while absorbing thermal energy from the sun through a parabolic trough collector and then storing it in a thermal storage to increase system efficiency and maintains system operation during low radiation. The heat is then transferred to the organic fluid in the ORC via a heat exchanger. The organic fluids to be used and analyzed in the ORC are hydrocarbons R600a and R290.

  3. Electrically conductive carbon nanofiber/paraffin wax composites for electric thermal storage

    International Nuclear Information System (INIS)

    Zhang Kun; Han Baoguo; Yu Xun

    2012-01-01

    Highlights: ► Carbon nanofiber (CNF)/paraffin wax composite is found to be a promising electric thermal storage material. ► The thermal storage capacity of CNF/paraffin wax composite is five times of traditional electric thermal storage material. ► CNF is shown to be an effective conductive filler for the composite. - Abstract: The research of electric thermal storage (ETS) has attracted a lot of attention recently, which converts off-peak electrical energy into thermal energy and release it later at peak hours. In this study, new electric thermal storage composites are developed by employing paraffin wax as thermal storage media and carbon nanofiber (CNF) as conductive fillers. Electric heating and thermal energy release performances of the CNF/paraffin wax composites are experimentally investigated. Experimental results show that, when the composites are heated to about 70 °C, the developed electrically conductive CNF/paraffin wax composites present a thermal storage capacity of about 280 kJ/kg, which is five times of that of traditional thermal storage medium such as ceramic bricks (54 kJ/kg). The CNF/paraffin wax composites can also effectively store the thermal energy and release the thermal energy in later hours.

  4. Electrical and thermal modeling of railguns

    International Nuclear Information System (INIS)

    Kerrisk, J.F.

    1984-01-01

    Electrical and thermal modeling of railguns at Los Alamos has been done for two purposes: (1) to obtain detailed information about the behavior of specific railgun components such as the rails, and (2) to predict overall performance of railgun tests. Detailed electrical and thermal modeling has concentrated on calculations of the inductance and surface current distribution of long parallel conductors in the high-frequency limit and on calculations of current and thermal diffusion in rails. Inductance calculations for various rail cross sections and for magnetic flux compression generators (MFCG) have been done. Inductance and current distribution results were compared with experimental measurements. Twodimensional calculations of current and thermal diffusion in rail cross sections have been done; predictions of rail heating and melting as a function of rail size and total current have been made. An overall performance model of a railgun and power supply has been developed and used to design tests at Los Alamos. The lumped-parameter circuit model uses results from the detailed inductance and current diffusion calculations along with other circuit component models to predict rail current and projectile acceleration, velocity, and position as a function of time

  5. Development of the ultra high efficiency thermal power generation facility

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Toshihiro

    2010-09-15

    In order to prevent global warming, attention is focused on nuclear power generation and renewable energy such as wind and solar power generation. The electric power suppliers of Japan are aiming to increase the amount of nuclear and non-fossil fuel power generation over 50% of the total power generation by 2020. But this means that the remaining half will still be of thermal power generation using fossil fuel and will still play an important role. Under such circumstances, further efficiency improvement of the thermal power generation and its aggressive implementation is ongoing in Japan.

  6. Thermodynamic analysis of pumped thermal electricity storage

    International Nuclear Information System (INIS)

    White, Alexander; Parks, Geoff; Markides, Christos N.

    2013-01-01

    The increasing use of renewable energy technologies for electricity generation, many of which have an unpredictably intermittent nature, will inevitably lead to a greater need for electricity storage. Although there are many existing and emerging storage technologies, most have limitations in terms of geographical constraints, high capital cost or low cycle life, and few are of sufficient scale (in terms of both power and storage capacity) for integration at the transmission and distribution levels. This paper is concerned with a relatively new concept which will be referred to here as Pumped Thermal Electricity Storage (PTES), and which may be able to make a significant contribution towards future storage needs. During charge, PTES makes use of a high temperature ratio heat pump to convert electrical energy into thermal energy which is stored as ‘sensible heat’ in two thermal reservoirs, one hot and one cold. When required, the thermal energy is then converted back to electricity by effectively running the heat pump backwards as a heat engine. The paper focuses on thermodynamic aspects of PTES, including energy and power density, and the various sources of irreversibility and their impact on round-trip efficiency. It is shown that, for given compression and expansion efficiencies, the cycle performance is controlled chiefly by the ratio between the highest and lowest temperatures in each reservoir rather than by the cycle pressure ratio. The sensitivity of round-trip efficiency to various loss parameters has been analysed and indicates particular susceptibility to compression and expansion irreversibility

  7. Nuclear Power as a Basis for Future Electricity Generation

    Science.gov (United States)

    Pioro, Igor; Buruchenko, Sergey

    2017-12-01

    It is well known that electrical-power generation is the key factor for advances in industry, agriculture, technology and the level of living. Also, strong power industry with diverse energy sources is very important for country independence. In general, electrical energy can be generated from: 1) burning mined and refined energy sources such as coal, natural gas, oil, and nuclear; and 2) harnessing energy sources such as hydro, biomass, wind, geothermal, solar, and wave power. Today, the main sources for electrical-energy generation are: 1) thermal power - primarily using coal and secondarily - natural gas; 2) “large” hydro power from dams and rivers and 3) nuclear power from various reactor designs. The balance of the energy sources is from using oil, biomass, wind, geothermal and solar, and have visible impact just in some countries. In spite of significant emphasis in the world on using renewables sources of energy, in particular, wind and solar, they have quite significant disadvantages compared to “traditional” sources for electricity generation such as thermal, hydro, and nuclear. These disadvantages include low density of energy, which requires large areas to be covered with wind turbines or photovoltaic panels or heliostats, and dependence of these sources on Mother Nature, i.e., to be unreliable ones and to have low (20 - 40%) or very low (5 - 15%) capacity factors. Fossil-fueled power plants represent concentrated and reliable source of energy. Also, they operate usually as “fast-response” plants to follow rapidly changing electrical-energy consumption during a day. However, due to combustion process they emit a lot of carbon dioxide, which contribute to the climate change in the world. Moreover, coal-fired power plants, as the most popular ones, create huge amount of slag and ash, and, eventually, emit other dangerous and harmful gases. Therefore, Nuclear Power Plants (NPPs), which are also concentrated and reliable source of energy

  8. Study of thermoelectric systems applied to electric power generation

    International Nuclear Information System (INIS)

    Rodriguez, A.; Vian, J.G.; Astrain, D.; Martinez, A.

    2009-01-01

    A computational model has been developed in order to simulate the thermal and electric behavior of thermoelectric generators. This model solves the nonlinear system of equations of the thermoelectric and heat transfer equations. The inputs of the program are the thermoelectric parameters as a function of temperature and the boundary conditions, (room temperature and residual heat flux). The outputs are the temperature values of all the elements forming the thermoelectric generator, (performance, electric power, voltage and electric current generated). The model solves the equation system using the finite difference method and semi-empirical expressions for the convection coefficients. A thermoelectric electric power generation test bench has been built in order to validate and determine the accuracy of the computational model, which maximum error is lower than 5%. The objective of this study is to create a design tool that allows us to solve the system of equations involved in the electric generation process without needing to impose boundary conditions that are not known in the design phase, such as the temperature of the Peltier modules. With the computational model, we study the influence of the heat flux supplied as well as the room temperature on the electric power generated.

  9. Integrated Electrical and Thermal Grid Facility - Testing of Future Microgrid Technologies

    Directory of Open Access Journals (Sweden)

    Sundar Raj Thangavelu

    2015-09-01

    Full Text Available This paper describes the Experimental Power Grid Centre (EPGC microgrid test facility, which was developed to enable research, development and testing for a wide range of distributed generation and microgrid technologies. The EPGC microgrid facility comprises a integrated electrical and thermal grid with a flexible and configurable architecture, and includes various distributed energy resources and emulators, such as generators, renewable, energy storage technologies and programmable load banks. The integrated thermal grid provides an opportunity to harness waste heat produced by the generators for combined heat, power and cooling applications, and support research in optimization of combined electrical-thermal systems. Several case studies are presented to demonstrate the testing of different control and operation strategies for storage systems in grid-connected and islanded microgrids. One of the case studies also demonstrates an integrated thermal grid to convert waste heat to useful energy, which thus far resulted in a higher combined energy efficiency. Experiment results confirm that the facility enables testing and evaluation of grid technologies and practical problems that may not be apparent in a computer simulated environment.

  10. High-frequency thermal-electrical cycles for pyroelectric energy conversion

    International Nuclear Information System (INIS)

    Bhatia, Bikram; Damodaran, Anoop R.; Cho, Hanna; Martin, Lane W.; King, William P.

    2014-01-01

    We report thermal to electrical energy conversion from a 150 nm thick BaTiO 3 film using pyroelectric cycles at 1 kHz. A microfabricated platform enables temperature and electric field control with temporal resolution near 1 μs. The rapid electric field changes as high as 11 × 10 5  kV/cm-s, and temperature change rates as high as 6 × 10 5  K/s allow exploration of pyroelectric cycles in a previously unexplored operating regime. We investigated the effect of phase difference between electric field and temperature cycles, and electric field and temperature change rates on the electrical energy generated from thermal-electrical cycles based on the pyroelectric Ericsson cycle. Complete thermodynamic cycles are possible up to the highest cycle rates tested here, and the energy density varies significantly with phase shifts between temperature and electric field waveforms. This work could facilitate the design and operation of pyroelectric cycles at high cycle rates, and aid in the design of new pyroelectric systems

  11. Natural gas and electricity generation in New South Wales

    International Nuclear Information System (INIS)

    Webb, G.

    2001-01-01

    In its Profile of the Australian Electricity Industry, ABARE noted that NSW was the first State in Australia to unbundle the operations of its State owned electricity industry. The process commenced in 1991, when the Electricity Commission of NSW was renamed Pacific Power and reorganised into six generation and transmission sectors. The power generation fuel mix for NSW in 1999-2000 was as follows: black coal, 97 percent and natural gas, 3 percent. NSW has also imported some brown coal generated electricity from Victoria in recent years. The import of cheap brown coal power from this State due to a marked increase in the availability of brown coal base-load generators in the Latrobe Valley forced some surplus black coal generating capacity in NSW to be withdrawn from the marketplace. Four generating units were closed down in 1998 two 500 MW units at Liddell and two 300 MW units at Munmorah. Further prospects for natural gas are reported to be good; its share in the thermal electricity generation market is forecasted to rise from 3 percent in 1999-2000 to 12 percent in 2014-1015

  12. Evaluation of the Effect of Operating Parameters on Thermal Performance of an Integrated Starter Generator in Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Moo-Yeon Lee

    2015-08-01

    Full Text Available The belt-driven-type integrated starter generator motor in a hybrid electric vehicle is vulnerable to thermal problems owing to its high output power and proximity to the engine. These problems may cause demagnetization and insulation breakdown, reducing the performance and durability of the motor. Hence, it is necessary to evaluate the thermal performance and enhance the cooling capacity of the belt-driven type Integrated Starter Generator. In this study, the internal temperature variations of the motor were investigated with respect to the operating parameters, particularly the rotation speed and environment temperature. At a maximum ambient temperature of 105 °C and rotation speed (motor design point of 4500 rpm, the coil of the motor was heated to approximately 189 °C in generating mode. The harsh conditions of the starting mode were analyzed by assuming that the motor operates during the start-up time at a maximum ambient temperature of 105 °C and rotation speed (motor design point of 800 rpm; the coil was heated to approximately 200 °C, which is close to the insulation temperature limit. The model for analyzing the thermal performance of the ISG was verified by comparing its results with those obtained through a generating-mode-based experiment

  13. Thermal and Electrical Analysis of Mars Rover RTGs

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred; Or, Chuen T; Skrabek, Emanuel A

    2012-01-19

    The RTG designs described in the preceding paper in these proceedings were analyzed for their thermal and electrical performance. Each analysis consisted of coupled thermal, thermoelectric, and electrical analyses, using Fairchild-generated specialized computer codes. These were supplemented with preliminary structural and mass analyses. For each design, various cases representing different operating conditions (water-cooled/radiation-cooled, BOM/EOM, summer/winter, day/night) and different thermoelectric performance assumptions (from conservative to optimistic) were analyzed; and for every case, the heat flow rates, temperatures and electrical performance of each layer of thermoelectric elements and of the overall RTG were determined. The analyses were performed in great detail, to obtain accurate answers permitting meaningful comparisons between different designs. The results presented show the RTG performance achievable with current technology, and the performance improvements that would be achievable with various technology developments.

  14. Electro-thermal analysis of Lithium Iron Phosphate battery for electric vehicles

    Science.gov (United States)

    Saw, L. H.; Somasundaram, K.; Ye, Y.; Tay, A. A. O.

    2014-03-01

    Lithium ion batteries offer an attractive solution for powering electric vehicles due to their relatively high specific energy and specific power, however, the temperature of the batteries greatly affects their performance as well as cycle life. In this work, an empirical equation characterizing the battery's electrical behavior is coupled with a lumped thermal model to analyze the electrical and thermal behavior of the 18650 Lithium Iron Phosphate cell. Under constant current discharging mode, the cell temperature increases with increasing charge/discharge rates. The dynamic behavior of the battery is also analyzed under a Simplified Federal Urban Driving Schedule and it is found that heat generated from the battery during this cycle is negligible. Simulation results are validated with experimental data. The validated single cell model is then extended to study the dynamic behavior of an electric vehicle battery pack. The modeling results predict that more heat is generated on an aggressive US06 driving cycle as compared to UDDS and HWFET cycle. An extensive thermal management system is needed for the electric vehicle battery pack especially during aggressive driving conditions to ensure that the cells are maintained within the desirable operating limits and temperature uniformity is achieved between the cells.

  15. Summary assessment of solar thermal parabolic dish technology for electrical power generation

    Science.gov (United States)

    Penda, P. L.; Fujita, T.; Lucas, J. W.

    1985-01-01

    An assessment is provided of solar thermal parabolic dish technology for electrical power generation. The assessment is based on the development program undertaken by the Jet Propulsion Laboratory for the U.S. Department of Energy and covers the period from the initiation of the program in 1976 through mid-1984. The program was founded on developing components and subsystems that are integrated into parabolic dish power modules for test and evaluation. The status of the project is summarized in terms of results obtained through testing of modules, and the implications of these findings are assessed in terms of techno-economic projections and market potential. The techno-economic projections are based on continuation of an evolutionary technological development program and are related to the accomplishments of the program as of mid-1984. The accomplishments of the development effort are summarized for each major subsystem including concentrators, receivers, and engines. The ramifications of these accomplishments are assessed in the context of developmental objectives and strategies.

  16. Point of view regarding the antitrust policy related to the electricity and thermal power generation sector in Romania

    International Nuclear Information System (INIS)

    Alexe, Fl.; Ionescu, M.

    1996-01-01

    At present, generation, transmission and selling of power in Romania is actually a monopoly of RENEL (The Romanian Electricity Authority). Moreover, RENEL covers an important share of the heat required by the great district heat consumers and industry (steam). Medium and long term programs for RENEL restructuring aims at moving the power distribution and selling sectors out of RENEL and at restructuring the generation sector. The present papers focuses mainly on those issues related to power generation sector privatization meant to promote a real competition in the field of power generation. To reach this purpose new regulations are necessary to ensure the access to the power system of various consumers satisfying certain technical requirements. This regards also all the independent power producers of electricity and possibly of thermal power (for instance the cogeneration power plants with less than or close to 50 MW). At the same time new concepts such as 'contracted power' and 'transit (wiring) tax' should be implemented in the near future in the business relations. Competition in this field will lead to the development of power market and the enhancement of power investments. (author). 3 refs

  17. Nuclear Power and Ghana's Future Electricity Generation

    International Nuclear Information System (INIS)

    Ennison, I.; Dzobo, M.

    2011-01-01

    One of the major challenges facing Ghana in her developmental efforts is the generation of adequate and affordable electricity to meet increasing demand. Problems with the dependency on hydro power has brought insecurity in electricity supply due to periodic droughts. Thermal power systems have been introduced into the electricity generation mix to complement the hydro power supply but there are problems associated with their use. The high price of crude oil on the international market has made them expensive to run and the supply of less expensive gas from Steps are being taken to run the thermal plants on less expensive gas from Nigeria has delayed due to conflicts in the Niger Delta region and other factors. The existing situation has therefore called for the diversification of the electricity generation mix so as to ensure energy security and affordable power supply. This paper presents the nuclear option as a suitable alternative energy source which can be used to address the energy supply problems facing the nation as well the steps being taken towards its introduction in the national energy mix. In addition, electricity demand projections using the MAED model as well as other studies are presented. The expected electricity demand of 350000 GWh (4000MWyr) in 2030, exceeds the total electricity supply capability of the existing hydropower system, untapped hydro resources and the maximum amount of gas that can be imported from Nigeria through the West Africa pipeline. Also presented is a technological assessment on the type of nuclear reactor to be used. The technological assessment which was done based on economics, grid size, technological maturity, passive safety and standardization of reactor design, indicate that a medium sized pressurized water reactor (i.e. a PWR with capacity 300MW to 700MW) is the most favourable type of reactor. In addition the challenges facing the implementation of the nuclear power programme in Ghana are presented. (author)

  18. Hydrolysis Batteries: Generating Electrical Energy during Hydrogen Absorption.

    Science.gov (United States)

    Xiao, Rui; Chen, Jun; Fu, Kai; Zheng, Xinyao; Wang, Teng; Zheng, Jie; Li, Xingguo

    2018-02-19

    The hydrolysis reaction of aluminum can be decoupled into a battery by pairing an Al foil with a Pd-capped yttrium dihydride (YH 2 -Pd) electrode. This hydrolysis battery generates a voltage around 0.45 V and leads to hydrogen absorption into the YH 2 layer. This represents a new hydrogen absorption mechanism featuring electrical energy generation during hydrogen absorption. The hydrolysis battery converts 8-15 % of the thermal energy of the hydrolysis reaction into usable electrical energy, leading to much higher energy efficiency compared to that of direct hydrolysis. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The Efficiency Improvement by Combining HHO Gas, Coal and Oil in Boiler for Electricity Generation

    Directory of Open Access Journals (Sweden)

    Chia-Nan Wang

    2017-02-01

    Full Text Available Electricity is an essential energy that can benefit our daily lives. There are many sources available for electricity generation, such as coal, natural gas and nuclear. Among these sources, coal has been widely used in thermal power plants that account for about 41% of the worldwide electricity supply. However, these thermal power plants are also found to be a big pollution source to our environment. There is a need to explore alternative electricity sources and improve the efficiency of electricity generation. This research focuses on improving the efficiency of electricity generation through the use of hydrogen and oxygen mixture (HHO gas. In this research, experiments have been conducted to investigate the combined effects of HHO gas with other fuels, including coal and oil. The results show that the combinations of HHO with coal and oil can improve the efficiency of electricity generation while reducing the pollution to our environment.

  20. Electrical generator

    International Nuclear Information System (INIS)

    Purdy, D.L.

    1976-01-01

    A nuclear heart pacer having a heat-to-electricity converter including a solid-state thermoelectric unit embedded in rubber which is compressed to impress hydrostatic precompression on the unit is described. The converter and the radioactive heat source are enclosed in a container which includes the electrical circuit components for producing and controlling the pulses; the converter and components being embedded in rubber. The portions of the rubber in the converter and in the container through which heat flows between the radioactive primary source and the hot junction and between the cold junction and the wall of the container are of thermally conducting silicone rubber. The 238 Pu primary radioactive source material is encapsuled in a refractory casing of WC-222 (T-222) which in turn is encapsuled in a corrosion-resistant casing of platinum rhodium, a diffusion barrier separating the WC-222 and the Pt--Rh casings. The Pt--Rh casing is in a closed basket of tantalum. The tantalum protects the Pt--Rh from reacting with other materials during cremation of the host, if any. The casings and basket suppress the transmission of hard x rays generated by the alpha particles from the 238 Pu. The outside casing of the pacer is typically of titanium but its surface is covered by an electrically insulating coating, typically epoxy resin, except over a relatively limited area for effective electrical grounding to the body of the host. It is contemplated that the pacer will be inserted in the host with the exposed titanium engaging a non-muscular region of the body

  1. Mechanical, Thermal, and Electrical Energy Storage in a Single Working Body: Electrification and Thermal Effects upon Pressure-Induced Water Intrusion-Extrusion in Nanoporous Solids.

    Science.gov (United States)

    Grosu, Yaroslav; Mierzwa, Michał; Eroshenko, Valentine A; Pawlus, Sebastian; Chorażewski, Mirosław; Nedelec, Jean-Marie; Grolier, Jean-Pierre E

    2017-03-01

    This paper presents the first experimental evidence of pronounced electrification effects upon reversible cycle of forced water intrusion-extrusion in nanoporous hydrophobic materials. Recorded generation of electricity combined with high-pressure calorimetric measurements improves the energy balance of {nanoporous solid + nonwetting liquid} systems by compensating mechanical and thermal energy hysteresis in the cycle. Revealed phenomena provide a novel way of "mechanical to electrical" and/or "thermal to electrical" energy transformation with unprecedented efficiency and additionally open a perspective to increase the efficiency of numerous energy applications based on such systems taking advantage of electricity generation during operational cycle.

  2. Status of thermal power generation in India-Perspectives on capacity, generation and carbon dioxide emissions

    International Nuclear Information System (INIS)

    Ghosh, Subhodip

    2010-01-01

    India's reliance on fossil-fuel based electricity generation has aggravated the problem of high carbon dioxide (CO 2 ) emissions from combustion of fossil fuels, primarily coal, in the country's energy sector. The objective of this paper is to analyze thermal power generation in India for a four-year period and determine the net generation from thermal power stations and the total and specific CO 2 emissions. The installed generating capacity, net generation and CO 2 emissions figures for the plants have been compared and large generators, large emitters, fuel types and also plant vintage have been identified. Specific emissions and dates of commissioning of plants have been taken into account for assessing whether specific plants need to be modernized. The focus is to find out areas and stations which are contributing more to the total emissions from all thermal power generating stations in the country and identify the overall trends that are emerging.

  3. Implementation of portfolio theory to the analysis of electricity generation in Mexico

    International Nuclear Information System (INIS)

    Esquivel E, J.; Ramirez S, J. R.; Palacios H, J. C.

    2014-10-01

    As part of the activities of economic analysis to the National Energy Strategy 2013-2027 of Mexico has been developed a computational platform to support decision-making based on the risk and performance in obtaining the optimum combination of technologies involved in the electricity generation. To this end, they consider five technologies: combined cycle, thermal coal, nuclear, hydro and wind. Each technology has been analyzed independently based on the total cost of generation level (given in dl s/KWh or dl s/MWh), leaning on documents as the Poise 2012-2026 and COPAR 2013. Subsequently by portfolio theory proposed by Markowitz, that combination of technologies that provide a greater benefit in the electricity generation is determined. In this study we consider two base work areas on which the proposed portfolios are reflected. The conformation of work areas is derived from the National Energy Strategy 2013-2027, considering a scenario with fossil technologies (combined cycle, thermal coal and nuclear) and other, making greater emphasis on the use of renewable technologies (combined cycle, hydro and wind). Finally, four portfolios are presented, each one with different percentages of ownership of technology in electricity generation, verifying the risk and performance of each combination. Of the analyzed portfolios, one corresponds to the mix of technologies which are currently in the country. The remaining derive the percentage share of combined-cycle technology, by subtracting 10% of their contribution and distributing it in three ways: by increasing the 10% share of nuclear technology; increasing 10% contribution of thermal coal technology and finally, extending the 5% of the electricity generation of nuclear technology and 5% increase in the electricity generation by wind technology. (Author)

  4. Environmental degradation costs in electricity generation: The case of the Brazilian electrical matrix

    International Nuclear Information System (INIS)

    Alves, Laura Araujo; Uturbey, Wadaed

    2010-01-01

    The main purpose of this paper is to emphasize the importance of including environmental degradation costs in the long-term planning of the Brazilian electricity sector. To this aim, environmental external costs associated to both hydro-power and thermal-power electricity generation are investigated. Monetary valuation methodologies are applied and environmental degradation costs, expressed in per kWh of generated energy, are obtained for the main types of generation sources of the Brazilian electricity matrix. Both local pollution due to particulate matter emissions and global warming effects are assessed. A classification of the sources from the point of view of their impact on the environment is given. Degradation costs associated to the installed capacity expansion in the Brazilian electricity sector during the time horizon 2007-2016 are estimated. These resulting costs represent lower boundary damage estimates associated only with the energy to be generated during the period. Results indicate that local pollution caused by a small number of plants could be even more costly to society than global warming and, also, show the importance of considering not only unitary damage costs but the participation of each source on the generated energy during the time horizon, as a guide to planning and policy making.

  5. Influence of winding construction on starter-generator thermal processes

    Science.gov (United States)

    Grachev, P. Yu; Bazarov, A. A.; Tabachinskiy, A. S.

    2018-01-01

    Dynamic processes in starter-generators features high winding are overcurrent. It can lead to insulation overheating and fault operation mode. For hybrid and electric vehicles, new high efficiency construction of induction machines windings is proposed. Stator thermal processes need be considered in the most difficult operation modes. The article describes construction features of new compact stator windings, electromagnetic and thermal models of processes in stator windings and explains the influence of innovative construction on thermal processes. Models are based on finite element method.

  6. Electric Motor Thermal Management

    Energy Technology Data Exchange (ETDEWEB)

    Bennion, Kevin S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-01

    Thermal management enables more efficient and cost-effective motors. This Annual Merit Review presentation describes the technical accomplishments and progress in electric motor thermal management R&D over the last year. This project supports a broad industry demand for data, analysis methods, and experimental techniques to improve and better understand motor thermal management.

  7. Electrical power system integrated thermal/electrical system simulation

    International Nuclear Information System (INIS)

    Freeman, W.E.

    1992-01-01

    This paper adds thermal properties to previously developed electrical Saber templates and incorporates these templates into a functional Electrical Power Subsystem (EPS) simulation. These combined electrical and thermal templates enable the complete and realistic simulation of a vehicle EPS on-orbit. Applications include on-orbit energy balance determinations for system load changes, initial array and battery EPS sizing for new EPS development, and array and battery technology trade studies. This effort proves the versatility of the Saber simulation program in handling varied and complex simulations accurately and in a reasonable amount of computer time. 9 refs

  8. Electric Motor Thermal Management R&D. Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Bennion, Kevin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-04-01

    With the push to reduce component volumes, lower costs, and reduce weight without sacrificing performance or reliability, the challenges associated with thermal management increase for power electronics and electric motors. Thermal management for electric motors will become more important as the automotive industry continues the transition to more electrically dominant vehicle propulsion systems. The transition to more electrically dominant propulsion systems leads to higher-power duty cycles for electric drive systems. Thermal constraints place significant limitations on how electric motors ultimately perform, and as thermal management improves, there will be a direct trade-off between motor performance, efficiency, cost, and the sizing of electric motors to operate within the thermal constraints. The goal of this research project is to support broad industry demand for data, analysis methods, and experimental techniques to improve and better understand motor thermal management. Work in FY15 focused on two areas related to motor thermal management: passive thermal performance and active convective cooling. Passive thermal performance emphasized the thermal impact of materials and thermal interfaces among materials within an assembled motor. The research tasks supported the publication of test methods and data for thermal contact resistances and direction-dependent thermal conductivity within an electric motor. Active convective cooling focused on measuring convective heat-transfer coefficients using automatic transmission fluid (ATF). Data for average convective heat transfer coefficients for direct impingement of ATF jets was published. Also, experimental hardware for mapping local-scale and stator-scale convective heat transfer coefficients for ATF jet impingement were developed.

  9. Conceptual design of a demonstration reactor for electric power generation

    International Nuclear Information System (INIS)

    Asaoka, Y.; Hiwatari, R.; Okano, K.; Ogawa, Y.; Ise, H.; Nomoto, Y.; Kuroda, T.; Mori, S.; Shinya, K.

    2005-01-01

    Conceptual study on a demonstration plant for electric power generation, named Demo-CREST, was conducted based on the consideration that a demo-plant should have capacities both (1) to demonstrate electric power generation in a plant scale with moderate plasma performance, which will be achieved in the early stage of the ITER operation, and foreseeable technologies and materials and (2) to have a possibility to show an economical competitiveness with advanced plasma performance and high performance blanket systems. The plasma core was optimized to be a minimum size for both net electric power generation with the ITER basic plasma parameters and commercial-scale generation with advance plasma parameters, which would be attained by the end of ITER operation. The engineering concept, especially the breeding blanket structure and its maintenance scheme, is also optimized to demonstrate the tritium self-sustainability and maintainability of in-vessel components. Within the plasma performance as planned in the present ITER program, the net electric power from 0 MW to 500 MW is possible with the basic blanket system under the engineering conditions of maximum magnetic field 16 T, NBI system efficiency 50%, and NBI current drive power restricted to 200 MW. Capacities of stabilization of reversed shear plasma and the high thermal efficiency are additional factors for optimization of the advanced blanket. By replacing the blanket system with the advanced one of higher thermal efficiency, the net electric power of about 1000 MW is also possible so that the economic performance toward the commercial plant can be also examined with Demo-CREST. (author)

  10. The performance of residential micro-cogeneration coupled with thermal and electrical storage

    Science.gov (United States)

    Kopf, John

    Over 80% of residential secondary energy consumption in Canada and Ontario is used for space and water heating. The peak electricity demands resulting from residential energy consumption increase the reliance on fossil-fuel generation stations. Distributed energy resources can help to decrease the reliance on central generation stations. Presently, distributed energy resources such as solar photovoltaic, wind and bio-mass generation are subsidized in Ontario. Micro-cogeneration is an emerging technology that can be implemented as a distributed energy resource within residential or commercial buildings. Micro-cogeneration has the potential to reduce a building's energy consumption by simultaneously generating thermal and electrical power on-site. The coupling of a micro-cogeneration device with electrical storage can improve the system's ability to reduce peak electricity demands. The performance potential of micro-cogeneration devices has yet to be fully realized. This research addresses the performance of a residential micro-cogeneration device and it's ability to meet peak occupant electrical loads when coupled with electrical storage. An integrated building energy model was developed of a residential micro-cogeneration system: the house, the micro-cogeneration device, all balance of plant and space heating components, a thermal storage device, an electrical storage device, as well as the occupant electrical and hot water demands. This model simulated the performance of a micro-cogeneration device coupled to an electrical storage system within a Canadian household. A customized controller was created in ESP-r to examine the impact of various system control strategies. The economic performance of the system was assessed from the perspective of a local energy distribution company and an end-user under hypothetical electricity export purchase price scenarios. It was found that with certain control strategies the micro-cogeneration system was able to improve the

  11. Comparative assessment of electricity generation options in the Philippines

    International Nuclear Information System (INIS)

    Leonin, T.V.; Mundo, M.Q.; Venida, L.L.; Arriola, H.; Madrio, E.

    2001-01-01

    The development of a country specific data base on energy sources, facilities and technologies is presented in this paper. It also identified feasible national electricity generating options and electric power system expansion alternatives for the period 2000-2020, and conducted comparative assessments of these options based on economic and environmental considerations. The possible role of nuclear power in the country's future electric energy was also studied. The comparison of three electricity generating options were considered: coal-fired thermal power plant without flue gas desulfurization (FGD), coal-fired thermal power plant with FGD and combined cycle power plant with 300 MW generating capacity each. Based on the analysis of three alternatives, the use of coal-fired power plants equipped with flue gas desulfurization (FGD) should be seriously considered. The government is expected to pursue the full development of local energy sources such as hydropower, geothermal, coal, natural gas and other new and renewable energy sources. However, there will still be a major need for imported oil and coal fuel which will likely supply unidentified energy sources beyond 2010. In the case of nuclear power, the government has not firmed up definite plans for any construction of nuclear power plants after 2010. However, the long term energy development plan still includes the operation of at least two nuclear power plants by the 2020 and this long term range program has not been revised in the recent published updates. (Author)

  12. Evaluation of a portfolio of electricity generation, using dynamics of systems

    International Nuclear Information System (INIS)

    Franco Barrera, Juan Felipe; Dyner R, Isaac

    2004-01-01

    The construction of a Technological Portfolio in charge of a firm of electricity generation in Colombia leads to its study; among other is the case of Empresas Publicas de Medellin (EEPPM.), because this company is nowadays-building new electricity projects in Colombia. EEPPM. will provide electricity using a new technology in Colombia, which is wind power, for the national grid joining hydraulic and thermal generation. A System Dynamics (SD) model was constructed to represent the national power system, specially the EEPPM. Generation facilities, combining both hydraulic and thermal plants along with the new wind farm of EEPPM, the new Technological Portfolio can be represented. SD is useful to learn about the different variables considered in the model, in order to represent interactions, delays and feedbacks that are present in the considered system. The study of the EEPPM portfolio performance allows to understand not only the impact of the high investment in wind power technology, but to study its possible benefits for the portfolio, like Risk and Value at Risk (VaR) reductions. Furthermore, the simulations show the advantage of wind power generation during dry seasons, as ENSO oscillation

  13. Electricity storage using a thermal storage scheme

    Energy Technology Data Exchange (ETDEWEB)

    White, Alexander, E-mail: ajw36@cam.ac.uk [Hopkinson Laboratory, Cambridge University Engineering Department, Trumpington Street, Cambridge. CB2 1PZ (United Kingdom)

    2015-01-22

    The increasing use of renewable energy technologies for electricity generation, many of which have an unpredictably intermittent nature, will inevitably lead to a greater demand for large-scale electricity storage schemes. For example, the expanding fraction of electricity produced by wind turbines will require either backup or storage capacity to cover extended periods of wind lull. This paper describes a recently proposed storage scheme, referred to here as Pumped Thermal Storage (PTS), and which is based on “sensible heat” storage in large thermal reservoirs. During the charging phase, the system effectively operates as a high temperature-ratio heat pump, extracting heat from a cold reservoir and delivering heat to a hot one. In the discharge phase the processes are reversed and it operates as a heat engine. The round-trip efficiency is limited only by process irreversibilities (as opposed to Second Law limitations on the coefficient of performance and the thermal efficiency of the heat pump and heat engine respectively). PTS is currently being developed in both France and England. In both cases, the schemes operate on the Joule-Brayton (gas turbine) cycle, using argon as the working fluid. However, the French scheme proposes the use of turbomachinery for compression and expansion, whereas for that being developed in England reciprocating devices are proposed. The current paper focuses on the impact of the various process irreversibilities on the thermodynamic round-trip efficiency of the scheme. Consideration is given to compression and expansion losses and pressure losses (in pipe-work, valves and thermal reservoirs); heat transfer related irreversibility in the thermal reservoirs is discussed but not included in the analysis. Results are presented demonstrating how the various loss parameters and operating conditions influence the overall performance.

  14. Biomass gasification for electricity generation with internal combustion engines. Process efficiency

    International Nuclear Information System (INIS)

    Lesme-Jaén, René; Garcia Faure, Luis; Recio Recio, Angel; Oliva Ruiz, Luis; Pajarín Rodríguez, Juan; Revilla Suarez, Dennis

    2015-01-01

    Biomass is a renewable source of energy worldwide increased prospects for its potential and its lower environmental impact compared to fossil fuels. By processes and energy conversion technologies it is possible to obtain fuels in solid, liquid and gaseous form from any biomass. The biomass gasification is the thermal conversion thereof into a gas, which can be used for electricity production with the use of internal combustion engines with a certain level of efficiency, which depends on the characteristics of biomass and engines used. In this work the evaluation of thermal and overall efficiency of the gasification in Integrated Forestry Enterprise of Santiago de Cuba, designed to generate electricity from waste from the forest industry is presented. Is a downdraft gasifier reactor, COMBO-80 model and engine manufacturing Hindu (diesel) model Leyland modified to work with producer gas. The evaluation was carried out for different loads (electric power generated) engine from experimental measurements of flow and composition of the gas supplied to the engine. The results show that the motor operates with a thermal efficiency in the range of 20-32% with an overall efficiency between 12-25%. (full text)

  15. The Efficiency Improvement by Combining HHO Gas, Coal and Oil in Boiler for Electricity Generation

    OpenAIRE

    Chia-Nan Wang; Min-Tsong Chou; Hsien-Pin Hsu; Jing-Wein Wang; Sridhar Selvaraj

    2017-01-01

    Electricity is an essential energy that can benefit our daily lives. There are many sources available for electricity generation, such as coal, natural gas and nuclear. Among these sources, coal has been widely used in thermal power plants that account for about 41% of the worldwide electricity supply. However, these thermal power plants are also found to be a big pollution source to our environment. There is a need to explore alternative electricity sources and improve the efficiency of elec...

  16. Economic aspects of grid connected solar electricity generation

    International Nuclear Information System (INIS)

    Pharabod, F.

    1993-01-01

    Experience gained with available solar thermal technologies enlighten on options for research and development on solar electricity generation. The proposed analysis of new solar technologies concerns market, costs and profit viewpoint: - Systems under development have to fit with consumers' needs and utilities' specifications, technology is not the only item to study. - Expense headings depend on technological options and operation procedures such as size of the plant, solar only or hybrid concept. - Anticipation of revenues highly depends on direct insolation quality and on local conditions for introducing the electric power generated into the network: daily direct insolation measurements and annual local load curve are prerequisite data. Strategic advantages regarding environment and sustainable development are to be pointed out, specially in industrialized countries or for projects including financing institutions. As far as generating electric power on the grid is a major challenge in the development of a number of countries in the sun belt, cooperation between industrialized and developing countries, under the auspices of international organization, has to be promoted. (Author) 12 refs

  17. On the evolution, over four generations of paraboloidal dish solar thermal electric power systems

    International Nuclear Information System (INIS)

    Kaneff, S.

    1993-01-01

    After a decade of supplying useful power, the White Cliffs Paraboloidal Dish Solar Thermal Power Station (1100 km west of Sydney) is still operational and has provided major lessons and experience for subsequent developments; particularly for the Molokai/Alburquerque unit built jointly with Power Kinetics Inc (of Troy, USA) for the US Department of Energy. This has, in turn, given valuable guidance for the third generation system now nearing completion in Canberra and employing new collector concepts refined for commercial production and viability. Unlike much dish-oriented R and D, we consider systems of dish arrays supplying central plant as a more attractive proposition than assemblies of dish/engine units, for all but very small systems (<2 MWe). Development has recently commerce on the fourth generation technology which result in a 2 MWe dish system within 2 years, expected to be followed closely by a system of 10 to 20 MWe, preparatory to still larger systems, as the technology evolves and experience is gained. The rationale in this progression in based on the achievement of commercial cost-effectiveness in competition with other energy sources. The direction of evolution is becoming clear and application of the technology to broader spheres than electricity generation is likely. Because of the nature of production methods employed and the ease of installation, system implementation can be rapid. (Author) 29 refs

  18. Power Generation from a Radiative Thermal Source Using a Large-Area Infrared Rectenna

    Science.gov (United States)

    Shank, Joshua; Kadlec, Emil A.; Jarecki, Robert L.; Starbuck, Andrew; Howell, Stephen; Peters, David W.; Davids, Paul S.

    2018-05-01

    Electrical power generation from a moderate-temperature thermal source by means of direct conversion of infrared radiation is important and highly desirable for energy harvesting from waste heat and micropower applications. Here, we demonstrate direct rectified power generation from an unbiased large-area nanoantenna-coupled tunnel diode rectifier called a rectenna. Using a vacuum radiometric measurement technique with irradiation from a temperature-stabilized thermal source, a generated power density of 8 nW /cm2 is observed at a source temperature of 450 °C for the unbiased rectenna across an optimized load resistance. The optimized load resistance for the peak power generation for each temperature coincides with the tunnel diode resistance at zero bias and corresponds to the impedance matching condition for a rectifying antenna. Current-voltage measurements of a thermally illuminated large-area rectenna show current zero crossing shifts into the second quadrant indicating rectification. Photon-assisted tunneling in the unbiased rectenna is modeled as the mechanism for the large short-circuit photocurrents observed where the photon energy serves as an effective bias across the tunnel junction. The measured current and voltage across the load resistor as a function of the thermal source temperature represents direct current electrical power generation.

  19. Possibilities of electricity generation from solar and other renewable resources in Turkey

    International Nuclear Information System (INIS)

    Tasdemiroglu, E.

    1993-01-01

    The paper begins by reviewing the conventional power generation in the country. Increasing power demand due to rapid industrialization as well as the environmental consequences of power generation will be discussed. The potential of renewable energy resources including solar, biomass, wind, and wave and their role in the power generation will be pointed out. Among the strong alternatives are thermal power plants, and rural electricity production by photovoltaic and by small wind machines. Finally, the technical economic difficulties in adapting renewable electricity generation systems for the conditions of the country will be discussed. (Author) 22 refs

  20. Nuclear reactor capable of electric power generation during in-service inspection

    International Nuclear Information System (INIS)

    Nakamura, Shinsuke; Nogami, Hitoshi.

    1992-01-01

    The nuclear power plant according to the present invention can generate electric power even in a period when one of a pair of reactors is put to in-service inspection. That is, the nuclear power plant of the present invention comprises a system constitution of two nuclear reactors each of 50% thermal power and one turbine power generator of 100% electric power. Further, facilities of various systems relevant to the two reactors each of 50% thermal power, as a pair, are used in common as much as possible in order to reduce the cost for construction and maintenance/ inspection. Further, a reactor building and a turbine building disposed in adjacent with each for paired two reactors each of 50% thermal power are arranged vertically. This arrangement can facilitate the common use of the facilities for various systems and equipments to attain branching and joining of fluids in reactor feed water systems and main steam system pipelines easily with low pressure loss and low impact shocks. The facility utilization factor of such reactors is remarkably improved by doubling the period of continuous power generation. As a result, economic property is remarkably improved. (I.S.)

  1. Thermal burn and electrical injuries among electric utility workers, 1995-2004.

    Science.gov (United States)

    Fordyce, Tiffani A; Kelsh, Michael; Lu, Elizabeth T; Sahl, Jack D; Yager, Janice W

    2007-03-01

    This study describes the occurrence of work-related injuries from thermal-, electrical- and chemical-burns among electric utility workers. We describe injury trends by occupation, body part injured, age, sex, and circumstances surrounding the injury. This analysis includes all thermal, electric, and chemical injuries included in the Electric Power Research Institute (EPRI) Occupational Health and Safety Database (OHSD). There were a total of 872 thermal burn and electric shock injuries representing 3.7% of all injuries, but accounting for nearly 13% of all medical claim costs, second only to the medical costs associated with sprain- and strain-related injuries (38% of all injuries). The majority of burns involved less than 1 day off of work. The head, hands, and other upper extremities were the body parts most frequently injured by burns or electric shocks. For this industry, electric-related burns accounted for the largest percentage of burn injuries, 399 injuries (45.8%), followed by thermal/heat burns, 345 injuries (39.6%), and chemical burns, 51 injuries (5.8%). These injuries also represented a disproportionate number of fatalities; of the 24 deaths recorded in the database, contact with electric current or with temperature extremes was the source of seven of the fatalities. High-risk occupations included welders, line workers, electricians, meter readers, mechanics, maintenance workers, and plant and equipment operators.

  2. Equivalent Electrical Circuits of Thermoelectric Generators under Different Operating Conditions

    Directory of Open Access Journals (Sweden)

    Saima Siouane

    2017-03-01

    Full Text Available Energy harvesting has become a promising and alternative solution to conventional energy generation patterns to overcome the problem of supplying autonomous electrical systems. More particularly, thermal energy harvesting technologies have drawn a major interest in both research and industry. Thermoelectric Generators (TEGs can be used in two different operating conditions, under constant temperature gradient or constant heat flow. The commonly used TEG electrical model, based on a voltage source in series with an electrical resistance, shows its limitations especially under constant heat flow conditions. Here, the analytical electrical modeling, taking into consideration the internal and contact thermal resistances of a TEG under constant temperature gradient and constant heat flow conditions, is first given. To give further insight into the electrical behavior of a TEG module in different operating conditions, we propose a new and original way of emulating the above analytical expressions with usual electronics components (voltage source, resistors, diode, whose values are determined with the TEG’s parameters. Note that such a TEG emulation is particularly suited when designing the electronic circuitry commonly associated to the TEG, to realize both Maximum Power Point Tracking and output voltage regulation. First, the proposed equivalent electrical circuits are validated through simulation with a SPICE environment in static operating conditions using only one value of either temperature gradient or heat flow. Then, they are also analyzed in dynamic operating conditions where both temperature gradient and heat flow are considered as time-varying functions.

  3. Demonstration tokamak fusion power plant for early realization of net electric power generation

    International Nuclear Information System (INIS)

    Hiwatari, R.; Okano, K.; Asaoka, Y.; Shinya, K.; Ogawa, Y.

    2005-01-01

    A demonstration tokamak fusion power plant Demo-CREST is proposed as the device for early realization of net electric power generation by fusion energy. The plasma configuration for Demo-CREST is optimized to satisfy the electric breakeven condition (the condition for net electric power, P e net = 0 MW) with the plasma performance of the ITER reference operation mode. This optimization method is considered to be suitable for the design of a demonstration power plant for early realization of net electric power generation, because the demonstration power plant has to ensure the net electric generation. Plasma performance should also be more reliably achieved than in past design studies. For the plasma performance planned in the present ITER programme, net electric power from 0 to 500 MW is possible with Demo-CREST under the following engineering conditions: maximum magnetic field 16 T, thermal efficiency 30%, NBI system efficiency 50% and NBI current drive power restricted to 200 MW. By replacing the blanket system with one of higher thermal efficiency, a net electric power of about 1000 MW is also possible so that the performance of the commercial plant with Demo-CREST can also be studied from the economic point of view. The development path from the experimental reactor 'ITER' to the commercial plant 'CREST' through the demonstration power plant 'Demo-CREST' is proposed as an example of the fast track concept. (author)

  4. Thermoelectric System in Different Thermal and Electrical Configurations: Its Impact in the Figure of Merit

    Directory of Open Access Journals (Sweden)

    Alexander Vargas-Almeida

    2013-05-01

    Full Text Available In this work, we analyze different configurations of a thermoelectric system (TES composed of three thermoelectric generators (TEGs. We present the following considerations: (a TES thermally and electrically connected in series (SC; (b TES thermally and electrically connected in parallel (PSC; and (c parallel thermally and series electrical connection (SSC. We assume that the parameters of the TEGs are temperature-independent. The systems are characterized by three parameters, as it has been showed in recent investigations, namely, its internal electrical resistance, R, thermal conductance under open electrical circuit condition, K, and Seebeck coefficient α. We derive the equivalent parameters for each of the configurations considered here and calculate the Figure of Merit Z for the equivalent system. We show the impact of the configuration of the system on Z, and we suggest optimum configuration. In order to justify the effectiveness of the equivalent Figure of Merit, the corresponding efficiency has been calculated for each configuration.

  5. Transmutor demo unit and thermal into electrical energy transformation problems

    International Nuclear Information System (INIS)

    Matal, O.; Fiedler, J.

    1999-01-01

    In the three circuits layout of the transmutor the heat is transferred from the primary through the secondary circuits by a favourable heat carrier into the tertiary circuit where the thermal into electrical energy transformation in turbo-generator comes into force. Properties as well as parameters of the heat carrier in the secondary circuit affect basically both the conceptual layout of the tertiary circuit and consequently investments costs for its realization and the effectiveness of the transformation of thermal into electrical energy. For several heat carriers considered for the transmutor secondary circuit particular tertiary circuit concepts for the demonstration transmutor unit of approx. 15 W thermal power rate are analyzed, layout features and possibilities of turbogenerator selection are commented and investment costs as well as effectiveness of thermal into electrical energy transformation are estimated. Some of the results are as follows: (i) Heat carrier properties influence thermodynamics of the TDU water/steam cycle substantially. One of the dominant parameters is the melting (freezing) temperature of the heat carrier. (ii) Heat carrier properties influence investment costs of components of the TDU tertiary circuit substantially. Dominantly influenced are costs of the steam generator, steam turbine and high pressure regeneration system. (iii) If the heat carrier has to be a molten salt than a salt with a low melting temperature is recommended to be selected, for example KHF2. (iv) Eutectic alloy Pb-Bi as the heat carrier serves changes to design the TDU with efficient thermodynamics, with acceptable low investment costs of the tertiary as well as secondary circuit components and with an acceptable level of the nuclear safety

  6. Thermo-economic optimization of the impact of renewable generators on poly-generation smart-grids including hot thermal storage

    International Nuclear Information System (INIS)

    Rivarolo, M.; Greco, A.; Massardo, A.F.

    2013-01-01

    Highlights: ► We model a poly-generation grid including thermal storage and renewable generators. ► We analyze the impact of random renewable generators on the grid performance. ► We carry out the grid optimization using a time-dependent thermo-economic approach. ► We present the importance of the storage system to optimize the RES impact. - Abstract: In this paper, the impact of not controllable renewable energy generators (wind turbines and solar photovoltaic panels) on the thermo-economic optimum performance of poly-generation smart grids is investigated using an original time dependent hierarchical approach. The grid used for the analysis is the one installed at the University of Genoa for research activities. It is based on different prime movers: (i) 100 kWe micro gas turbine, (ii) 20 kWe internal combustion engine powered by gases to produce both electrical and thermal (hot water) energy and (iii) a 100 kWth adsorption chiller to produce cooling (cold water) energy. The grid includes thermal storage tanks to manage the thermal demand load during the year. The plant under analysis is also equipped with two renewable non-controllable generators: a small size wind turbine and photovoltaic solar panels. The size and the management of the system studied in this work have been optimized, in order to minimize both capital and variable costs. A time-dependent thermo-economic hierarchical approach developed by the authors has been used, considering the time-dependent electrical, thermal and cooling load demands during the year as problem constraints. The results are presented and discussed in depth and show the strong interaction between fossil and renewable resources, and the importance of an appropriate storage system to optimize the RES impact taking into account the multiproduct character of the grid under investigation.

  7. Thermally controlled comb generation and soliton modelocking in microresonators.

    Science.gov (United States)

    Joshi, Chaitanya; Jang, Jae K; Luke, Kevin; Ji, Xingchen; Miller, Steven A; Klenner, Alexander; Okawachi, Yoshitomo; Lipson, Michal; Gaeta, Alexander L

    2016-06-01

    We report, to the best of our knowledge, the first demonstration of thermally controlled soliton mode-locked frequency comb generation in microresonators. By controlling the electric current through heaters integrated with silicon nitride microresonators, we demonstrate a systematic and repeatable pathway to single- and multi-soliton mode-locked states without adjusting the pump laser wavelength. Such an approach could greatly simplify the generation of mode-locked frequency combs and facilitate applications such as chip-based dual-comb spectroscopy.

  8. Investigating the water consumption for electricity generation at Turkish power plants

    Science.gov (United States)

    El-Khozondar, Balkess; Aydinalp Koksal, Merih

    2017-11-01

    The water-energy intertwined relationship has recently gained more importance due to the high water consumption in the energy sector and to the limited availability of the water resources. The energy and electricity demand of Turkey is increasing rapidly in the last two decades. More thermal power plants are expected to be built in the near future to supply the rapidly increasing demand in Turkey which will put pressure on water availability. In this study, the water consumption for electricity generation at Turkish power plants is investigated. The main objectives of this study are to identify the amount of water consumed to generate 1 kWh of electricity for each generation technology currently used in Turkey and to investigate ways to reduce the water consumption at power plants expected to be built in the near future to supply the increasing demand. The various electricity generation technology mixture scenarios are analyzed to determine the future total and per generation water consumption, and water savings based on changes of cooling systems used for each technology. The Long-range Energy Alternatives Planning (LEAP) program is used to determine the minimum water consuming electricity generation technology mixtures using optimization approaches between 2017 and 2035.

  9. Recouping the thermal-to-electric conversion loss by the use of waste heat

    International Nuclear Information System (INIS)

    Bradley, W.J.

    1976-01-01

    This paper looks at ways to recoup the thermal-to-electric conversion loss of our thermal power generating stations. These stations now produce twice as much low-grade waste heat as they do electricity. We can improve the situation in two ways: by improving the station efficiency, and by utilizing the low-grade heat beneficially. The following options are examined: N 2 O 4 turbines condensing at 10 deg C; power from moderator waste heat; 50 MW heat pump for district heating; industrial parks with integrated waste heat upgrading station. (author)

  10. Thermal and electrical conductivities of Cd-Zn alloys

    International Nuclear Information System (INIS)

    Saatci, B; Ari, M; Guenduez, M; Meydaneri, F; Bozoklu, M; Durmus, S

    2006-01-01

    The composition and temperature dependences of the thermal and electrical conductivities of three different Cd-Zn alloys have been investigated in the temperature range of 300-650 K. Thermal conductivities of the Cd-Zn alloys have been determined by using the radial heat flow method. It has been found that the thermal conductivity decreases slightly with increasing temperature and the data of thermal conductivity are shifting together to the higher values with increasing Cd composition. In addition, the electrical measurements were determined by using a standard DC four-point probe technique. The resistivity increases linearly and the electrical conductivity decreases exponentially with increasing temperature. The resistivity and electrical conductivity are independent of composition of Cd and Zn. Also, the temperature coefficient of Cd-Zn alloys has been determined, which is independent of composition of Cd and Zn. Finally, Lorenz number has been calculated using the thermal and electrical conductivity values at 373 and 533 K. The results satisfy the Wiedemann-Franz (WF) relation at T 373 K), the WF relation could not hold and the phonon component contribution of thermal conductivity dominates the thermal conduction

  11. Method for protecting an electric generator

    Science.gov (United States)

    Kuehnle, Barry W.; Roberts, Jeffrey B.; Folkers, Ralph W.

    2008-11-18

    A method for protecting an electrical generator which includes providing an electrical generator which is normally synchronously operated with an electrical power grid; providing a synchronizing signal from the electrical generator; establishing a reference signal; and electrically isolating the electrical generator from the electrical power grid if the synchronizing signal is not in phase with the reference signal.

  12. Thermal electric power production

    International Nuclear Information System (INIS)

    Boehmer, S.

    2001-01-01

    The basic principle of a thermal power plant is to heat up water in the pipe system of a boiler to generate steam, which exits the boiler with high pressure and releases its energy to a tandem-arranged turbine. This energy is transmitted to a generator over a common shaft. The generated electricity is fed into the power supply system. The processed steam is condensed to water by means of a condenser and transferred back into the pipe system of the boiler (feed water circuit). In general the following techniques are applied for the combustion of solid, liquid and gaseous fuels: dry bottom boiler, wet bottom boiler, grate firing, fluidized bed combustion, gasification systems - integrated gasification combined cycle (IGCC), oil firing technique, gas firing technique. Residues from power plants are generated by the following processes and emission reduction measures: separation of bottom ash or boiler slag in the boiler; separation of fly ash (particulate matter) by means of filters or electric precipitators; desulphurization through lime additive processes, dry sorption or spray absorption processes and lime scrubbing processes; desulphurization according to Wellmann-Lord and to the Walther process; reduction of NO x emissions by selective catalytic reduction (SCR). In this case spent catalyst results as a waste unless it is recycled. No residues are generated by the following measures to reduce NO x emissions: minimization of nitrogen by selective non-catalytic reduction (SNCR); adaptations of the firing technology to avoid emissions - primary measures (low-NO x burners, CO reduction). However, this may change the quality of fly ash by increasing unburnt carbon. Combustion of fossil fuels (with the exception of gaseous fuels) and biomass generates large quantities of residues - with coal being the greatest contributor - either from the fuel itself in the form of ashes, or from flue gas cleaning measures. In coal-fired power plants huge amounts of inorganic residues

  13. Study on thermal electric conversion system for FBR plant. Investigation for effective EVST waste heat recovery system

    International Nuclear Information System (INIS)

    Maekawa, Isamu; Kurata, Chikatoshi

    2004-02-01

    Recently, it has been important to reuse discharged heat energy from present nuclear plant, especially from sodium cooled FBR, which are typical high temperature system, in the view of reduction of environmental burden and improvement of heat efficiency for plant. The thermal electric conversion system can work only the temperature difference and has been applied to the limited fields such as space or military, however, that results show good merits for reliability, maintenance free, and so on. Recently, the development of new thermal electric conversion elements has made remarkable progress. In this study, for the effective utilization of waste heat from Monju', the prototype plant of FBR, we made an investigation of electric power generating system maintaining the cooling faculty by applying the thermal electric conversion system to sodium cooling line of EVST. Using the new type iron based thermal electric conversion elements, which are plentiful, economical and good for environmental harmonization, we have calculated the amount of heat exchange and power generation from sodium cooling line of EVST, and have investigated the module sizing, cost and subject to be settled. The results were , (1)The amount of power generation from sodium cooling line of EVST is smaller about one figure than motive power of sodium cooler fan. However, if Seebeck coefficient and heat conductivity of iron based thermal electric conversion elements shall be improved, power from sodium cooling line shall be able to cover the motive power. (2) The amount of heat released from sodium cooling line after the installation of thermal electric conversion module covers the necessity to maintain the sodium cooling faculty. (3) In case of the installation of module to the sodium cooler, it should be reconstructed because of tube arrangement modification. In case of the installation of module to the sodium connecting line, air ventilation system is needed to suppress the room temperature. (4) As

  14. How is Electricity Generated from Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lajnef, D.

    2015-01-01

    Nuclear power is a proven, safe and clean source of power generation. A nuclear power plant is a thermal power station in which the heat source is a nuclear reactor. As is typical in all conventional thermal power stations the heat is used to generate steam which drives a steam turbine: the energy released from continuous fission of the atoms of the fuel is harnessed as heat in either a gas or water, and is used to produce steam. Nuclear Reactors are classified by several methods. It can be classified by type of nuclear reaction, by the moderator material, by coolant or by generation. There are several components common to most types of reactors: fuel, moderator, control rods, coolant, and containment. Nuclear reactor technology has been under continuous development since the first commercial exploitation of civil nuclear power in the 1950s. We can mention seven key reactor attributes that illuminate the essential differences between the various generations of reactors: cost effectiveness, safety, security and non-proliferation, fuel cycle, grid appropriateness and Economics. Today there are about 437 nuclear power reactors that are used to generate electricity in about 30 countries around the world. (author)

  15. The environmental paradox in generation: How South America is gradually becoming more dependent on thermal generation

    International Nuclear Information System (INIS)

    Arango, Santiago; Larsen, Erik R.

    2010-01-01

    There has been an increasing focus on global warming, emission of green house gases (GHG), and the problems this might create. In this article, we review the trend in sustainable and renewable electricity generation in South America, where the generation portfolio increasingly depends on thermal generation, in particular gas. South America is a region that has relatively low emissions, but the current development is not desirable in environmental terms. We analyze the underlying reasons for this development, which is related to security of supply, deregulation, and the cost of renewable energy. We review and discuss the policies to promote renewables in the region. We analyze the potential advantages and drawbacks of different types of market interventions, such as direct subsidies that create potentially strong market distortions, more sophisticated market interventions that might be less intrusive but not necessarily as effective as, e.g. firm energy markets. We also review market-based solutions such as the Clean Market Mechanism and its potential, and the use of renewable electricity in non-interconnected zones, which might be one of the most economically attractive applications of renewables. However, without a stronger and more aggressive intervention from the governments in the region it is unlikely that the increase in thermal generation can be stopped. (author)

  16. A review on battery thermal management in electric vehicle application

    Science.gov (United States)

    Xia, Guodong; Cao, Lei; Bi, Guanglong

    2017-11-01

    The global issues of energy crisis and air pollution have offered a great opportunity to develop electric vehicles. However, so far, cycle life of power battery, environment adaptability, driving range and charging time seems far to compare with the level of traditional vehicles with internal combustion engine. Effective battery thermal management (BTM) is absolutely essential to relieve this situation. This paper reviews the existing literature from two levels that are cell level and battery module level. For single battery, specific attention is paid to three important processes which are heat generation, heat transport, and heat dissipation. For large format cell, multi-scale multi-dimensional coupled models have been developed. This will facilitate the investigation on factors, such as local irreversible heat generation, thermal resistance, current distribution, etc., that account for intrinsic temperature gradients existing in cell. For battery module based on air and liquid cooling, series, series-parallel and parallel cooling configurations are discussed. Liquid cooling strategies, especially direct liquid cooling strategies, are reviewed and they may advance the battery thermal management system to a new generation.

  17. Harvesting electrical energy from torsional thermal actuation driven by natural convection.

    Science.gov (United States)

    Kim, Shi Hyeong; Sim, Hyeon Jun; Hyeon, Jae Sang; Suh, Dongseok; Spinks, Geoffrey M; Baughman, Ray H; Kim, Seon Jeong

    2018-06-07

    The development of practical, cost-effective systems for the conversion of low-grade waste heat to electrical energy is an important area of renewable energy research. We here demonstrate a thermal energy harvester that is driven by the small temperature fluctuations provided by natural convection. This harvester uses coiled yarn artificial muscles, comprising well-aligned shape memory polyurethane (SMPU) microfibers, to convert thermal energy to torsional mechanical energy, which is then electromagnetically converted to electrical energy. Temperature fluctuations in a yarn muscle, having a maximum hot-to-cold temperature difference of about 13 °C, were used to spin a magnetic rotor to a peak torsional rotation speed of 3,000 rpm. The electromagnetic energy generator converted the torsional energy to electrical energy, thereby producing an oscillating output voltage of up to 0.81 V and peak power of 4 W/kg, based on SMPU mass.

  18. Electrical and thermal conductivities in dense plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Faussurier, G., E-mail: gerald.faussurier@cea.fr; Blancard, C.; Combis, P.; Videau, L. [CEA, DAM, DIF, F-91297 Arpajon (France)

    2014-09-15

    Expressions for the electrical and thermal conductivities in dense plasmas are derived combining the Chester-Thellung-Kubo-Greenwood approach and the Kramers approximation. The infrared divergence is removed assuming a Drude-like behaviour. An analytical expression is obtained for the Lorenz number that interpolates between the cold solid-state and the hot plasma phases. An expression for the electrical resistivity is proposed using the Ziman-Evans formula, from which the thermal conductivity can be deduced using the analytical expression for the Lorenz number. The present method can be used to estimate electrical and thermal conductivities of mixtures. Comparisons with experiment and quantum molecular dynamics simulations are done.

  19. Parametric performance analysis of a concentrated photovoltaic co-generation system equipped with a thermal storage tank

    International Nuclear Information System (INIS)

    Imtiaz Hussain, M.; Lee, Gwi Hyun

    2015-01-01

    Highlights: • Both thermal and electrical powers varied by changing surface area of collector. • Thermal stratification and total system power were increased at critical flow rate. • Parametric analysis of the CPVC system offers to determine the desired outcome. • Thermal and electrical outputs varied by changing the focal length of Fresnel lens. - Abstract: This article presents a parametric study of a concentrated photovoltaic co-generation (CPVC) system with an attached thermal storage tank. The CPVC system utilized dual-axis tracker and multiple solar energy collector (SEC) modules and forced cooling system. Each SEC module comprised 16 triple-junction solar cells, copper tube absorbers, and 16 Fresnel lenses were aligned against each solar cell. This study investigated all possible parameters that can affect the CPVC system performance, including the collector area, solar irradiation, inlet temperature, and mass flow rate. The surface area of the collector and the thermal power were increased by increasing the number of SEC modules connected in series; however, the electrical power output decreased from the first to the fourth SEC module consecutively. At the measured optimal flow rate, mixing and thermal diffusion in the storage tank were decreased, and the total power generation from the CPVC system was increased. Variations in the thermal and electrical power outputs were also observed when the focal length of the Fresnel lens was changed. This parametric analysis enables the CPVC system to obtain the desired output by varying the combination of operational and geometrical parameters

  20. Electrical-thermal coupling of induction machine for improved ...

    African Journals Online (AJOL)

    Electrical-thermal coupling of induction machine for improved thermal performance. ... Nigerian Journal of Technology ... The interaction of its electrical and mechanical parts leads to an increase in temperature which if not properly monitored ...

  1. Investigation of the Promotion of Wind Power Consumption Using the Thermal-Electric Decoupling Techniques

    Directory of Open Access Journals (Sweden)

    Shuang Rong

    2015-08-01

    Full Text Available In the provinces of north China, combined heat and electric power generations (CHP are widely utilized to provide both heating source and electricity. While, due to the constraint of thermal-electric coupling within CHP, a mass of wind turbines have to offline operate during heating season to maintain the power grid stability. This paper proposes a thermal-electric decoupling (TED approach to release the energy waste. Within the thermal-electric decoupling system, heat storage and electric boiler/heat pump are introduced to provide an auxiliary thermal source during hard peak shaving period, thus relying on the participation of an outside heat source, the artificial electric power output change interval could be widened to adopt more wind power and reduce wind power curtailment. Both mathematic models and methods are proposed to calculate the evaluation indexes to weight the effect of TED, by using the Monte Carlo simulation technique. Numerical simulations have been conducted to demonstrate the effectiveness of the proposed methods, and the results show that the proposed approach could relieve up to approximately 90% of wind power curtailment and the ability of power system to accommodate wind power could be promoted about 32%; moreover, the heating source is extended, about 300 GJ heat could be supplied by TED during the whole heating season, which accounts for about 18% of the total heat need.

  2. Solar thermal power systems point-focusing thermal and electric applications projects. Volume 1: Executive summary

    Science.gov (United States)

    Marriott, A.

    1980-01-01

    The activities of the Point-Focusing Thermal and Electric Applications (PETEA) project for the fiscal year 1979 are summarized. The main thrust of the PFTEA Project, the small community solar thermal power experiment, was completed. Concept definition studies included a small central receiver approach, a point-focusing distributed receiver system with central power generation, and a point-focusing distributed receiver concept with distributed power generation. The first experiment in the Isolated Application Series was initiated. Planning for the third engineering experiment series, which addresses the industrial market sector, was also initiated. In addition to the experiment-related activities, several contracts to industry were let and studies were conducted to explore the market potential for point-focusing distributed receiver (PFDR) systems. System analysis studies were completed that looked at PFDR technology relative to other small power system technology candidates for the utility market sector.

  3. Improving Thermal and Electrical Efficiency in Photovoltaic Thermal Systems for Sustainable Cooling System Integration

    Directory of Open Access Journals (Sweden)

    Mohammad Alobaid

    2018-06-01

    Full Text Available Research into photovoltaic thermal systems is important in solar technologies as photovoltaic thermal systems are designed to produce both electrical and thermal energy, this can lead to improved performance of the overall system. The performance of photovoltaic thermal systems is based on several factors that include photovoltaic thermal materials, design, ambient temperature, inlet and outlet fluid temperature and photovoltaic cell temperature. The aim of this study is to investigate the effect of photovoltaic thermal outlet water temperatures and solar cell temperature on both electrical and thermal efficiency for different range of inlet water temperature. To achieve this, a mathematical model of a photovoltaic thermal system was developed to calculate the anticipated system performance. The factors that affect the efficiency of photovoltaic thermal collectors were discussed and the outlet fluid temperature from the photovoltaic thermal is investigated in order to reach the highest overall efficiency for the solar cooling system. An average thermal and electrical efficiency of 65% and 13.7%, respectively, was achieved and the photovoltaic thermal mathematical model was validated with experimental data from literature.

  4. Electric Motor Thermal Management R&D

    Energy Technology Data Exchange (ETDEWEB)

    Bennion, Kevin

    2016-06-07

    Thermal management enables more efficient and cost-effective motors. This Annual Merit Review presentation describes the technical accomplishments and progress in electric motor thermal management R&D over the last year. This project supports a broad industry demand for data, analysis methods, and experimental techniques to improve and better understand motor thermal management.

  5. Southeast Regional Assessment Study: an assessment of the opportunities of solar electric power generation in the Southeastern United States

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    The objective of this study was to identify and assess opportunities for demonstration and large scale deployment of solar electric facilities in the southeast region and to define the technical, economic, and institutional factors that can contribute to an accelerated use of solar energy for electric power generation. Graphs and tables are presented indicating the solar resource potential, siting opportunities, energy generation and use, and socioeconomic factors of the region by state. Solar electric technologies considered include both central station and dispersed solar electric generating facilities. Central stations studied include solar thermal electric, wind, photovoltaic, ocean thermal gradient, and biomass; dispersed facilities include solar thermal total energy systems, wind, and photovoltaic. The value of solar electric facilities is determined in terms of the value of conventional facilities and the use of conventional fuels which the solar facilities can replace. Suitable cost and risk sharing mechanisms to accelerate the commercialization of solar electric technologies in the Southeast are identified. The major regulatory and legal factors which could impact on the commercialization of solar facilities are reviewed. The most important factors which affect market penetration are reviewed, ways to accelerate the implementation of these technologies are identified, and market entry paths are identified. Conclusions and recommendations are presented. (WHK)

  6. Electromechanically generating electricity with a gapped-graphene electric generator

    Science.gov (United States)

    Dressen, Donald; Golovchenko, Jene

    2015-03-01

    We demonstrate the fabrication and operation of a gapped-graphene electric generator (G-GEG) device. The G-GEG generates electricity from the mechanical oscillation of droplets of electrolytes and ionic liquids. The spontaneous adsorption of ionic species on graphene charges opposing electric double-layer capacitors (EDLCs) on each half of the device. Modulating the area of contact between the droplet and graphene leads to adsorption/desorption of ions, effectively charging/discharging each EDLC and generating a current. The flow of current supports a potential difference across the G-GEG due to the device's internal impedance. Both the magnitude and polarity of the induced current and voltage show a strong dependence on the type of ionic species used, suggesting that certain ions interact more strongly with graphene than others. We find that a simple model circuit consisting of an AC current source in series with a resistor and a time-varying capacitor accurately predicts the device's dynamic behavior. Additionally, we discuss the effect of graphene's intrinsic quantum capacitance on the G-GEG's performance and speculate on the utility of the device in the context of energy harvesting.

  7. The limits to solar thermal electricity

    International Nuclear Information System (INIS)

    Trainer, Ted

    2014-01-01

    The potential and limits of solar thermal power systems depend primarily on their capacity to meet electricity demand in mid-winter, and the associated cost, storage and other implications. Evidence on output and costs is analysed. Most attention is given to central receivers. Problems of low radiation levels, embodied energy costs, variability and storage are discussed and are found to set significant difficulties for large scale solar thermal supply in less than ideal latitudes and seasons. It is concluded that for solar thermal systems to meet a large fraction of anticipated global electricity demand in winter would involve prohibitive capital costs. - Highlights: • Output and capital cost data for various solar thermal technologies is examined. • Special attention is given to performance in winter. • Attention is also given to the effect of solar intermittency. • Implications for storage are considered. • It is concluded that there are significant limits to solar thermal power

  8. Conversion of Low Quality Waste Heat to Electric Power with Small-Scale Organic Rankine Cycle (ORC) Engine/Generator Technology

    Science.gov (United States)

    2016-06-01

    block (expander) that allows gas expansion and converts the energy into rotational work, • an electric induction generator driven from the power block...is in the form of waste heat – thermal energy emitted via hot exhaust and heat removal systems associated with engine and other electric generator ...than 250 ºC), improves energy efficiency by reducing energy consumption associated with electrical generation and reduces greenhouse gas emissions

  9. Solar thermal power plants for heat and electricity generation; Presentacion de plantas termosolares para generacion de calor y energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Estrada Cajigal, V [Solartronic S. A. de C. V., Cuernavaca (Mexico); Manzini, F; Sanchez, A [Laboratorio de Energia Solar (IIM-UNAM), Temixco (Mexico)

    1993-12-31

    Solar thermal technology is presented for concentration into a point for the production of heat and energy in small and large scale, emphasis is made on the capacity for the combination with current technologies using fossil fuels for electricity generation and process steam, increasing the global efficiency of the power plants and notably reducing the pollutants emission to the air during the insolation hours. It is successfully compared with other solar-thermal technologies. [Espanol] Se presenta la tecnologia termosolar de concentracion puntual para produccion de calor y de energia en pequena y gran escala, se enfatiza su capacidad de combinacion con las tecnologias actuales que utilizan combustibles fosiles para produccion de electricidad y vapor de proceso, aumentando la eficiencia global de las plantas y reduciendo notablemente sus emisiones contaminantes a la atmosfera durante las horas de insolacion. Se le compara exitosamente con otras tecnologias termosolares.

  10. Solar thermal power plants for heat and electricity generation; Presentacion de plantas termosolares para generacion de calor y energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Estrada Cajigal, V. [Solartronic S. A. de C. V., Cuernavaca (Mexico); Manzini, F.; Sanchez, A. [Laboratorio de Energia Solar (IIM-UNAM), Temixco (Mexico)

    1992-12-31

    Solar thermal technology is presented for concentration into a point for the production of heat and energy in small and large scale, emphasis is made on the capacity for the combination with current technologies using fossil fuels for electricity generation and process steam, increasing the global efficiency of the power plants and notably reducing the pollutants emission to the air during the insolation hours. It is successfully compared with other solar-thermal technologies. [Espanol] Se presenta la tecnologia termosolar de concentracion puntual para produccion de calor y de energia en pequena y gran escala, se enfatiza su capacidad de combinacion con las tecnologias actuales que utilizan combustibles fosiles para produccion de electricidad y vapor de proceso, aumentando la eficiencia global de las plantas y reduciendo notablemente sus emisiones contaminantes a la atmosfera durante las horas de insolacion. Se le compara exitosamente con otras tecnologias termosolares.

  11. Thermal efficiency improvements - an imperative for nuclear generating stations

    International Nuclear Information System (INIS)

    Hassanien, S.; Rouse, S.

    1997-01-01

    A one and a half percent thermal performance improvement of Ontario Hydro's operating nuclear units (Bruce B, Pickering B, and Darlington) means almost 980 GWh are available to the transmission system (assuming an 80% capacity factor). This is equivalent to the energy consumption of 34,000 electrically-heated homes in Ontario, and worth more than $39 million in revenue to Ontario Hydro Nuclear Generation. Improving nuclear plant thermal efficiency improves profitability (more GWh per unit of fuel) and competitiveness (cost of unit energy), and reduces environmental impact (less spent fuel and nuclear waste). Thermal performance will naturally decrease due to the age of the units unless corrective action is taken. Most Ontario Hydro nuclear units are ten to twenty years old. Some common causes for loss of thermal efficiency are: fouling and tube plugging of steam generators, condensers, and heat exchangers; steam leaks in the condenser due to valve wear, steam trap and drain leaks; deposition, pitting, cracking, corrosion, etc., of turbine blades; inadequate feedwater metering resulting from corrosion and deposition. This paper stresses the importance of improving the nuclear units' thermal efficiency. Ontario Hydro Nuclear has demonstrated energy savings results are achievable and affordable. Between 1994 and 1996, Nuclear reduced its energy use and improved thermal efficiency by over 430,000 MWh. Efficiency improvement is not automatic - strategies are needed to be effective. This paper suggests practical strategies to systematically improve thermal efficiency. (author)

  12. The generation of pollution-free electrical power from solar energy.

    Science.gov (United States)

    Cherry, W. R.

    1971-01-01

    Projections of the U.S. electrical power demands over the next 30 years indicate that the U.S. could be in grave danger from power shortages, undesirable effluence, and thermal pollution. An appraisal of nonconventional methods of producing electrical power is conducted, giving particular attention to the conversion of solar energy into commercial quantities of electrical power by solar cells. It is found that 1% of the land area of the 48 states could provide the total electrical power requirements of the U.S. in the year 1990. The ultimate method of generating vast quantities of electrical power would be from a series of synchronous satellites which beam microwave power back to earth to be used wherever needed. Present high manufacturing costs of solar cells could be substantially reduced by using massive automated techniques employing abundant low cost materials.

  13. Integration of plug-in hybrid electric vehicles in a regional wind-thermal power system

    International Nuclear Information System (INIS)

    Goeransson, Lisa; Karlsson, Sten; Johnsson, Filip

    2010-01-01

    This study investigates consequences of integrating plug-in hybrid electric vehicles (PHEVs) in a wind-thermal power system supplied by one quarter of wind power and three quarters of thermal generation. Four different PHEV integration strategies, with different impacts on the total electric load profile, have been investigated. The study shows that PHEVs can reduce the CO 2 -emissions from the power system if actively integrated, whereas a passive approach to PHEV integration (i.e. letting people charge the car at will) is likely to result in an increase in emissions compared to a power system without PHEV load. The reduction in emissions under active PHEV integration strategies is due to a reduction in emissions related to thermal plant start-ups and part load operation. Emissions of the power sector are reduced with up to 4.7% compared to a system without PHEVs, according to the simulations. Allocating this emission reduction to the PHEV electricity consumption only, and assuming that the vehicles in electric mode is about 3 times as energy efficient as standard gasoline operation, total emissions from PHEVs would be less than half the emissions of a standard car, when running in electric mode.

  14. Apparatuses and methods for generating electric fields

    Science.gov (United States)

    Scott, Jill R; McJunkin, Timothy R; Tremblay, Paul L

    2013-08-06

    Apparatuses and methods relating to generating an electric field are disclosed. An electric field generator may include a semiconductive material configured in a physical shape substantially different from a shape of an electric field to be generated thereby. The electric field is generated when a voltage drop exists across the semiconductive material. A method for generating an electric field may include applying a voltage to a shaped semiconductive material to generate a complex, substantially nonlinear electric field. The shape of the complex, substantially nonlinear electric field may be configured for directing charged particles to a desired location. Other apparatuses and methods are disclosed.

  15. Electric power generation

    International Nuclear Information System (INIS)

    Pinske, J.D.

    1981-01-01

    Apart from discussing some principles of power industry the present text deals with the different ways of electric power generation. Both the conventional methods of energy conversion in heating and water power stations and the facilities for utilizing regenerative energy sources (sun, wind, ground heat, tidal power) are considered. The script represents the essentials of the lecture of the same name which is offered to the students of the special subject 'electric power engineering' at the Fachhochschule Hamburg. It does not require any special preliminary knowledge except for the general principles of electrical engineering. It is addressing students of electrical engineering who have passed their preliminary examination at technical colleges and universities. Moreover, it shall also be of use for engineers who want to obtain a quick survey of the structure and the operating characteristics of the extremely different technical methods of power generation. (orig.) [de

  16. Heat and electricity generating methods

    International Nuclear Information System (INIS)

    Buter, J.

    1977-01-01

    A short synopsis on the actual methods of heating of lodgings and of industrial heat generation is given. Electricity can be generated in steam cycles heated by burning of fossil fuels or by nuclear energy. A valuable contribution to the electricity economy is produced in the hydroelectric power plants. Besides these classical methods, also the different procedures of direct electricity generation are treated: thermoelectric, thermionic, magnetohydrodynamic power sources, solar and fuel cells. (orig.) [de

  17. CHP in Switzerland from 1990 to 1998. Thermal power generation including combined heat and power

    International Nuclear Information System (INIS)

    Kaufmann, U.

    1999-01-01

    The results of a study on thermal power generation in Switzerland show that combined heat and power (CHP) systems have grown rapidly. Statistics are presented on the development of CHP-based power and also on thermal power stations without waste heat usage. Figures are given for gas and steam turbine installations, combined gas and steam turbine stations and motor-driven CHP units. Power production is categorised, separating small and large (over 1 Megawatt electrical) power generation facilities. On-site, distributed power generation at consumers' premises and the geographical distribution of plant is described

  18. Electrical Generation for More-Electric Aircraft Using Solid Oxide Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Whyatt, Greg A.; Chick, Lawrence A.

    2012-04-01

    This report examines the potential for Solid-Oxide Fuel Cells (SOFC) to provide electrical generation on-board commercial aircraft. Unlike a turbine-based auxiliary power unit (APU) a solid oxide fuel cell power unit (SOFCPU) would be more efficient than using the main engine generators to generate electricity and would operate continuously during flight. The focus of this study is on more-electric aircraft which minimize bleed air extraction from the engines and instead use electrical power obtained from generators driven by the main engines to satisfy all major loads. The increased electrical generation increases the potential fuel savings obtainable through more efficient electrical generation using a SOFCPU. However, the weight added to the aircraft by the SOFCPU impacts the main engine fuel consumption which reduces the potential fuel savings. To investigate these relationships the Boeing 787­8 was used as a case study. The potential performance of the SOFCPU was determined by coupling flowsheet modeling using ChemCAD software with a stack performance algorithm. For a given stack operating condition (cell voltage, anode utilization, stack pressure, target cell exit temperature), ChemCAD software was used to determine the cathode air rate to provide stack thermal balance, the heat exchanger duties, the gross power output for a given fuel rate, the parasitic power for the anode recycle blower and net power obtained from (or required by) the compressor/expander. The SOFC is based on the Gen4 Delphi planar SOFC with assumed modifications to tailor it to this application. The size of the stack needed to satisfy the specified condition was assessed using an empirically-based algorithm. The algorithm predicts stack power density based on the pressure, inlet temperature, cell voltage and anode and cathode inlet flows and compositions. The algorithm was developed by enhancing a model for a well-established material set operating at atmospheric pressure to reflect the

  19. Radioisotopes Thermal Generators and its applications; Generadores térmicos de radioisótopos y sus aplicaciones

    Energy Technology Data Exchange (ETDEWEB)

    Ahnert, C.

    2016-07-01

    An historical review of the technologies for electricity generation using the decay heat of the radioisotopes is done. The technologies to convert the heat into electricity in the RTG (Radioisotopes Thermal Generators) Systems are described. The past, todays and future applications of RTG are described, to provide electricity to equipment in spatial satellites and spacecraft, lighthouse tower and sea bouys, submarine rovers, etc. At the end the safety characteristics and international regulations for RTG are mentioned.

  20. High thermal conductivity connector having high electrical isolation

    Science.gov (United States)

    Nieman, Ralph C.; Gonczy, John D.; Nicol, Thomas H.

    1995-01-01

    A method and article for providing a low-thermal-resistance, high-electrical-isolation heat intercept connection. The connection method involves clamping, by thermal interference fit, an electrically isolating cylinder between an outer metallic ring and an inner metallic disk. The connection provides durable coupling of a heat sink and a heat source.

  1. The potential of nuclear energy to generate clean electric power in Brazil

    International Nuclear Information System (INIS)

    Stecher, Luiza C.; Sabundjian, Gaiane; Menzel, Francine; Giarola, Rodrigo S.; Coelho, Talita S.

    2013-01-01

    The generation of electricity in Brazil is concentrated in hydroelectric generation, renewable and clean source, but that does not satisfy all the demand and leads to necessity of a supplementary thermal sources portion. Considering the predictions of increase in demand for electricity in the next years, it becomes necessary to insert new sources to complement the production taking into account both the volume being produced and the needs of environmental preservation. Thus, nuclear power can be considered a potential supplementary source for electricity generation in Brazil as well as the country has large reserves of fissile material, the generation emits no greenhouse gases, the country has technological mastery of the fuel cycle and it enables the production of large volumes of clean energy. The objective of this study is to demonstrate the potential of nuclear energy in electricity production in Brazil cleanly and safely, ensuring the supplies necessary to maintain the country's economic growth and the increased demand sustainable. For this, will be made an analysis of economic and social indicators of the characteristics of our energy matrix and the availability of our sources, as well as a description of the nuclear source and arguments that justify a higher share of nuclear energy in the matrix of the country. Then, after these analysis, will notice that the generation of electricity from nuclear source has all the conditions to supplement safely and clean supply of electricity in Brazil. (author)

  2. Characterization of solar thermal concepts for electricity generation: Volume 1, Analyses and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.A.; Dirks, J.A.; Brown, D.R.; Drost, M.K.; Antoniac, Z.A.; Ross, B.A.

    1987-03-01

    This study is aimed at providing a relative comparison of the thermodynamic and economic performance in electric applications of several concepts that have been studied and developed in the DOE solar thermal program. Since the completion of earlier systems comparison studies in the late 1970's, there have been a number of years of progress in solar thermal technology. This progress has included development of new solar components, improvements in component and system design detail, construction of working systems, and collection of operating data on the systems. This study provides an updating of the expected performance and cost of the major components and the overall system energy cost for the concepts evaluated. The projections in this study are for the late 1990's time frame, based on the capabilities of the technologies that could be expected to be achieved with further technology development.

  3. Thermal Performance of Motor and Inverter in an Integrated Starter Generator System for a Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Sung Chul Kim

    2013-11-01

    Full Text Available If the integrated starter generator (ISG motor and inverter operate under continuously high loading conditions, the system’s performance and durability will decrease and the heat dissipation requirements will increase. Therefore, in this study, we developed two cooling designs for the ISG motor and inverter, and then carried out both a model analysis and an experiment on the fluid flow and thermal characteristics of the system under various operating conditions. As the outdoor temperature increased from 25 °C to 95 °C, the coil temperature of the air-cooled motor increased by about 82 °C. Under the harsh-air condition of 95 °C, the coil of the air-cooled motor increased to a maximum temperature of about 158.5 °C. We also determined that the temperature of the metal-oxide-semiconductor field-effect transistor (MOSFET chip in the liquid-cooled inverter increased to a maximum temperature of about 96.8 °C under a coolant flow rate of 4 L/min and a coolant temperature of 65 °C. The observed thermal performance of the ISG motor and inverter using the proposed cooling structures was found to be sufficient for heat loads under various real driving conditions for a hybrid electric vehicle (HEV.

  4. Quantity, Quality, and Availability of Waste Heat from United States Thermal Power Generation.

    Science.gov (United States)

    Gingerich, Daniel B; Mauter, Meagan S

    2015-07-21

    Secondary application of unconverted heat produced during electric power generation has the potential to improve the life-cycle fuel efficiency of the electric power industry and the sectors it serves. This work quantifies the residual heat (also known as waste heat) generated by U.S. thermal power plants and assesses the intermittency and transport issues that must be considered when planning to utilize this heat. Combining Energy Information Administration plant-level data with literature-reported process efficiency data, we develop estimates of the unconverted heat flux from individual U.S. thermal power plants in 2012. Together these power plants discharged an estimated 18.9 billion GJ(th) of residual heat in 2012, 4% of which was discharged at temperatures greater than 90 °C. We also characterize the temperature, spatial distribution, and temporal availability of this residual heat at the plant level and model the implications for the technical and economic feasibility of its end use. Increased implementation of flue gas desulfurization technologies at coal-fired facilities and the higher quality heat generated in the exhaust of natural gas fuel cycles are expected to increase the availability of residual heat generated by 10.6% in 2040.

  5. Electricity generation cost

    International Nuclear Information System (INIS)

    Bald, M.

    1984-01-01

    Also questions of efficiency play a part in the energy discussion. In this context, the economic evaluation of different energy supply variants is of importance. Especially with regard to the generation of electric power there have been discussions again and again during the last years on the advantage of the one or the other kind of electric power generation. In the meantime, a large number of scientific studies has been published on this topic which mainly deal with comparisons of the costs of electric power generated by hard coal or nuclear energy, i.e. of those energy forms which still have the possibilities of expansion. The following part shows a way for the evaluation of efficiency comparisons which starts from simplified assumptions and which works with arithmetical aids, which don't leave the area of the fundamental operations. The general comprehensibility is paid for with cuts on ultimate analytical and arithmetical precision. It will, however, turn out that the results achieved by this method don't differ very much from those which have been won by scientific targets. (orig./UA) [de

  6. Electrical and thermal behavior of unsaturated soils: experimental results

    Science.gov (United States)

    Nouveau, Marie; Grandjean, Gilles; Leroy, Philippe; Philippe, Mickael; Hedri, Estelle; Boukcim, Hassan

    2016-05-01

    When soil is affected by a heat source, some of its properties are modified, and in particular, the electrical resistivity due to changes in water content. As a result, these changes affect the thermal properties of soil, i.e., its thermal conductivity and diffusivity. We experimentally examine the changes in electrical resistivity and thermal conductivity for four soils with different grain size distributions and clay content over a wide range of temperatures, from 20 to 100 °C. This temperature range corresponds to the thermal conditions in the vicinity of a buried high voltage cable or a geothermal system. Experiments were conducted at the field scale, at a geothermal test facility, and in the laboratory using geophysical devices and probing systems. The results show that the electrical resistivity decreases and the thermal conductivity increases with temperature up to a critical temperature depending on soil types. At this critical temperature, the air volume in the pore space increases with temperature, and the resulting electrical resistivity also increases. For higher temperatures , the thermal conductivity increases sharply with temperature up to a second temperature limit. Beyond it, the thermal conductivity drops drastically. This limit corresponds to the temperature at which most of the water evaporates from the soil pore space. Once the evaporation is completed, the thermal conductivity stabilizes. To explain these experimental results, we modeled the electrical resistivity variations with temperature and water content in the temperature range 20 - 100°C, showing that two critical temperatures influence the main processes occurring during heating at temperatures below 100 °C.

  7. Heat operated cryogenic electrical generator

    International Nuclear Information System (INIS)

    Fletcher, J.C.; Wang, T.C.; Saffren, M.M.; Elleman, D.D.

    1975-01-01

    An electrical generator useful for providing electrical power in deep space, is disclosed. The subject electrical generator utilizes the unusual hydrodynamic property exhibited by liquid helium as it is converted to and from a superfluid state to cause opposite directions of rotary motion for a rotor cell thereof. The physical motion of said rotor cell is employed to move a magnetic field provided by a charged superconductive coil mounted on the exterior of said cell. An electrical conductor is placed in surrounding proximity to said cell to interact with the moving magnetic field provided by the superconductive coil and thereby generate electrical energy. A heat control arrangement is provided for the purpose of causing the liquid helium to be partially converted to and from a superfluid state by being cooled and heated, respectively. (U.S.)

  8. Optimal joint scheduling of electrical and thermal appliances in a smart home environment

    International Nuclear Information System (INIS)

    Shirazi, Elham; Zakariazadeh, Alireza; Jadid, Shahram

    2015-01-01

    Highlights: • Thermal appliances are scheduled based on desired temperature and energy prices. • A discomfort index has been introduced within the home energy scheduling model. • Appliances are scheduled based on activity probability and desired options. • Starting probability depends on the social random factor and consumption behavior. - Abstract: With the development of home area network, residents have the opportunity to schedule their power usage in the home by themselves aiming at reducing electricity expenses. Moreover, as renewable energy sources are deployed in home, a home energy management system needs to consider both energy consumption and generation simultaneously to minimize the energy cost. In this paper, a smart home energy management model has been presented in which electrical and thermal appliances are jointly scheduled. The proposed method aims at minimizing the electricity cost of a residential customer by scheduling various type of appliances considering the residents consumption behavior, seasonal probability, social random factor, discomfort index and appliances starting probability functions. In this model, the home central controller receives the electricity price information, environmental factors data as well as the resident desired options in order to optimally schedule appliances including electrical and thermal. The scheduling approach is tested on a typical home including variety of home appliances, a small wind turbine, photovoltaic panel, combined heat and power unit, boiler and electrical and thermal storages over a 24-h period. The results show that the scheduling of different appliances can be reached simultaneously by using the proposed formulation. Moreover, simulation results evidenced that the proposed home energy management model exhibits a lower cost and, therefore, is more economical.

  9. Natural gas for electric power generation: Strategic issues, risks and opportunities

    International Nuclear Information System (INIS)

    Linderman, C.

    1992-01-01

    Natural gas is again being regarded as a significant fuel for electric power generation. It was once a predominant fuel for utilities in gas-producing areas, but natural gas consumption declined greatly after the 1973 oil shock because of reduced electricity demand and increased coal and nuclear generation. Moreover, wellhead price and other forms of regulation produced gas shortages in the 1970s. The resurgence of natural gas in future resource plans stems from its inherent ideal fuel characteristics: short lead time; low capital costs; small increments of modular capacity; delivered close to load centers; environmentally benign, preferable to oil and coal; and potential for high thermal efficiency in gas turbines. Natural gas, if available and attractively priced, is an ideal fuel for electric power generation. No other fuel shares these attractive characteristics, and utilities, facing higher than expected load growth, are relying on an increasing proportion of gas-fired combustion turbines, combined cycle plants, and cogeneration to meet a growing, yet uncertain, future demand for electricity. Despite these desirable operating characteristics, the varied past and uncertain future of natural gas markets raise legitimate concerns about the riskiness of current utility natural gas strategies. This report, which summarizes the major findings from research efforts, is intended to help utility decision-makers understand the full range of risks they face with natural gas electric power generation and to identify actions they can take to mitigate those risks

  10. An electrical method for the measurement of the thermal and electrical conductivity of reduced graphene oxide nanostructures.

    Science.gov (United States)

    Schwamb, Timo; Burg, Brian R; Schirmer, Niklas C; Poulikakos, Dimos

    2009-10-07

    This paper introduces an electrical four-point measurement method enabling thermal and electrical conductivity measurements of nanoscale materials. The method was applied to determine the thermal and electrical conductivity of reduced graphene oxide flakes. The dielectrophoretically deposited samples exhibited thermal conductivities in the range of 0.14-2.87 W m(-1) K(-1) and electrical conductivities in the range of 6.2 x 10(2)-6.2 x 10(3) Omega(-1) m(-1). The measured properties of each flake were found to be dependent on the duration of the thermal reduction and are in this sense controllable.

  11. A renewable electric power and heat autonomous generator; Un generateur autonome d'electricite et de chaleur renouvelables

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The society ENERGIESTRO developed an electric power and heat generator allowing the electricity and the renewable heat of a little building, without the electric network. The energy source comes from a thermal engine supplied by biofuels. The document presents the technical characteristics and the advantages of this innovation. (A.L.B.)

  12. Horizontal steam generator thermal-hydraulics

    Energy Technology Data Exchange (ETDEWEB)

    Ubra, O. [SKODA Praha Company, Prague (Czechoslovakia); Doubek, M. [Czech Technical Univ., Prague (Czechoslovakia)

    1995-09-01

    Horizontal steam generators are typical components of nuclear power plants with pressure water reactor type VVER. Thermal-hydraulic behavior of horizontal steam generators is very different from the vertical U-tube steam generator, which has been extensively studied for several years. To contribute to the understanding of the horizontal steam generator thermal-hydraulics a computer program for 3-D steady state analysis of the PGV-1000 steam generator has been developed. By means of this computer program, a detailed thermal-hydraulic and thermodynamic study of the horizontal steam generator PGV-1000 has been carried out and a set of important steam generator characteristics has been obtained. The 3-D distribution of the void fraction and 3-D level profile as functions of load and secondary side pressure have been investigated and secondary side volumes and masses as functions of load and pressure have been evaluated. Some of the interesting results of calculations are presented in the paper.

  13. Day-Ahead Self-Scheduling of Thermal Generator in Competitive Electricity Market Using Hybrid PSO

    DEFF Research Database (Denmark)

    Pindoriya, N.M.; Singh, Sri Niwas; Østergaard, Jacob

    2009-01-01

    in day-ahead energy market subject to operational constraints and 2) at the same time, to minimize the risk due to uncertainty in price forecast. Therefore, it is a conflicting biobjective optimization problem which has both binary and continuous optimization variables considered as constrained mixed......This paper presents a hybrid particle swarm optimization algorithm (HPSO) to solve the day-ahead selfscheduling for thermal power producer in competitive electricity market. The objective functions considered to model the selfscheduling problem are: 1) to maximize the profit from selling energy...... integer nonlinear programming. To demonstrate the effectiveness of the proposed method for self-scheduling in a dayahead energy market, the locational margin price (LMP) forecast uncertainty in PJM electricity market is considered. An adaptive wavelet neural network (AWNN) is used to forecast the dayahead...

  14. Integrated Vehicle Thermal Management - Combining Fluid Loops in Electric Drive Vehicles (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Rugh, J. P.

    2013-07-01

    Plug-in hybrid electric vehicles and electric vehicles have increased vehicle thermal management complexity, using separate coolant loop for advanced power electronics and electric motors. Additional thermal components result in higher costs. Multiple cooling loops lead to reduced range due to increased weight. Energy is required to meet thermal requirements. This presentation for the 2013 Annual Merit Review discusses integrated vehicle thermal management by combining fluid loops in electric drive vehicles.

  15. Thermo-electrical systems for the generation of electricity

    International Nuclear Information System (INIS)

    Bitschi, A.; Froehlich, K.

    2010-01-01

    This article takes a look at theoretical models concerning thermo-electrical systems for the generation of electricity and demonstrations of technology actually realised. The potentials available and developments are discussed. The efficient use of energy along the whole generation and supply chain, as well as the use of renewable energy sources are considered as being two decisive factors in the attainment of a sustainable energy supply system. The large amount of unused waste heat available today in energy generation, industrial processes, transport systems and public buildings is commented on. Thermo-electric conversion systems are discussed and work being done on the subject at the Swiss Federal Institute of Technology in Zurich is discussed. The findings are discussed and results are presented in graphical form

  16. Composite electric generator equipped with steam generator for heating reactor coolant

    International Nuclear Information System (INIS)

    Watabe, Masaharu; Soman, Yoshindo; Kawanishi, Kohei; Ota, Masato.

    1997-01-01

    The present invention concerns a composite electric generator having coolants, as a heating source, of a PWR type reactor or a thermonuclear reactor. An electric generator driving gas turbine is disposed, and a superheater using a high temperature exhaust gas of the gas turbine as a heating source is disposed, and main steams are superheated by the superheater to elevate the temperature at the inlet of the turbine. This can increase the electric generation capacity as well as increase the electric generation efficiency. In addition, since the humidity in the vicinity of the exit of the steam turbine is reduced, occurrence of loss and erosion can be suppressed. When cooling water of the thermonuclear reactor is used, the electric power generated by the electric generator driven by the gas turbine can be used upon start of the thermonuclear reactor, and it is not necessary to dispose a large scaled special power source in the vicinity, which is efficient. (N.H.)

  17. Simultaneous Thermal and Gamma Radiation Aging of Electrical Cable Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, Leonard S.

    2018-04-11

    The polymers used for insulation in nuclear power plant electrical cables are susceptible to aging during long term operation. Elevated temperature is the primary contributor to changes in polymer structure that result loss of mechanical and electrical properties, but gamma radiation is also a significant source of degradation for polymers used within relevant plant locations. Despite many years of polymer degradation research, the combined effects of simultaneous exposure to thermal and radiation stress are not well understood. As nuclear operators contemplate and prepare for extended operations beyond initial license periods, a predictive understanding of exposure-based cable material degradation is becoming an increasingly important input to safety, licensing, operations and economic decisions. We are focusing on carefully-controlled simultaneous thermal and gamma radiation accelerating aging and characterization of the most common nuclear cable polymers to understand the relative contributions of temperature, time, dose and dose rate to changes in cable polymer material structure and properties. Improved understanding of cable performance in long term operation will help support continued sustainable nuclear power generation.

  18. Bony ankylosis following thermal and electrical injury

    Energy Technology Data Exchange (ETDEWEB)

    Balen, P.F.; Helms, C.A. [Dept. of Radiology, Duke University Medical Center, Durham, NC (United States)

    2001-07-01

    Objective. Bony ankylosis has been described following trauma, paralysis, psoriasis, Reiter's syndrome, ankylosing spondylitis, juvenile chronic arthritis and rheumatoid arthritis. Reports of bony ankylosis following thermal and electrical injury are limited.Design and patients. Thirteen cases of burn-related joint ankylosis in four patients are presented.Conclusion. Patients with burns from thermal or electrical injury may develop bony ankylosis among other radiographic manifestations. This bony ankylosis may result either from bridging extra-articular heterotopic ossification with preservation of the underlying joint or from intra-articular fusion due to joint destruction. (orig.)

  19. The electric power engineering handbook electric power generation, transmission, and distribution

    CERN Document Server

    Grigsby, Leonard L

    2012-01-01

    Featuring contributions from worldwide leaders in the field, the carefully crafted Electric Power Generation, Transmission, and Distribution, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) provides convenient access to detailed information on a diverse array of power engineering topics. Updates to nearly every chapter keep this book at the forefront of developments in modern power systems, reflecting international standards, practices, and technologies. Topics covered include: * Electric Power Generation: Nonconventional Methods * Electric Power Generation

  20. Comparative risk assessment for electricity generation

    International Nuclear Information System (INIS)

    Thoene, E.; Kallenbach, U.

    1988-01-01

    The following conclusions are drawn: There is no 'zero-risk option' in electricity generation. Risk comparison meets with considerable problems relating to available data and methods. Taking into account the existing uncertainties, technology ranking in terms of risks involved cannot be done, but the major risk elements of the various electricity generating systems can be clearly identified. The risks defined cannot be interpreted so as to lead to an abolishment of certain techniques due to risks involved, particularly if one sees the risks from electricity generation in relation to other health hazards. The use of coal for electricity generation clearly ranks top with regard to occupational risks and hazards to public health. (orig./HP) [de

  1. A balanced strategy in managing steam generator thermal performance

    International Nuclear Information System (INIS)

    Hu, M. H.; Nelson, P. R.

    2009-01-01

    This paper presents a balanced strategy in managing thermal performance of steam generator designed to deliver rated megawatt thermal (MWt) and megawatt electric (MWe) power without loss with some amount of thermal margin. A steam generator (SG) is a boiling heat exchanger whose thermal performance may degrade because of steam pressure loss. In other words, steam pressure loss is an indicator of thermal performance degradation. Steam pressure loss is mainly a result of either 1) tube scale induced poor boiling or 2) tube plugging historically resulting from tubing corrosion, wear due to flow induced tube vibration or loose parts impact. Thermal performance degradation was historically due to tube plugging but more recently it is due to poor boiling caused by more bad than good constituents of feedwater impurities. The whole SG industry still concentrates solely on maintenance programs towards preventing causes for tube plugging and yet almost no programs on maintaining adequate boiling of fouled tubes. There can be an acceptable amount of tube scale that provides excellent boiling capacity without tubing corrosion, as operational experience has repeatedly demonstrated. Therefore, future maintenance has to come up balanced programs for allocating limited resources in both maintaining good boiling capacity and preventing tube plugging. This paper discusses also thermal performance degradation due to feedwater impurity induced blockage of tube support plate and thus subsequent water level oscillations, and how to mitigate them. This paper provides a predictive management of tube scale for maintaining adequate steam pressure and stable water level without loss in MWt/MWe or recovering from steam pressure loss or water level oscillations. This paper offers a balanced strategy in managing SG thermal performance to fulfill its mission. Such a strategy is even more important in view of the industry trend in pursuing extended power uprate as high as 20 percent

  2. Load following generation in nuclear power plants by latent thermal energy storage

    International Nuclear Information System (INIS)

    Abe, Yoshiyuki; Takahashi, Yoshio; Kamimoto, Masayuki; Sakamoto, Ryuji; Kanari, Katsuhiko; Ozawa, Takeo

    1985-01-01

    The recent increase in nuclear power plants and the growing difference between peak and off-peak demands imperatively need load following generation in nuclear power plants to meet the time-variant demands. One possible way to resolve the problem is, obviously, a prompt reaction conrol in the reactors. Alternatively, energy storage gives another sophisticated path to make load following generation in more effective manner. Latent thermal energy storage enjoys high storage density and allows thermal extraction at nearly constant temperature, i.e. phase change temperature. The present report is an attempt to evaluate the feasibility of load following electric power generation in nuclear plants (actually Pressurized Water Reactors) by latent thermal energy storage. In this concept, the excess thermal energy in the off-peak period is stored in molten salt latent thermal energy storage unit, and additional power output is generated in auxiliary generator in the peak demand duration using the stored thermal energy. The present evaluation gives encouraging results and shows the primary subject to be taken up at first is the compatibility of candidate storage materials with inexpensive structural metal materials. Chapter 1 denotes the background of the present report, and Chapter 2 reviews the previous studies on the peak load coverage by thermal energy storage. To figure out the concept of the storage systems, present power plant systems and possible constitution of storage systems are briefly shown in Chapter 3. The details of the evaluation of the candidate storage media, and the compilation of the materials' properties are presented in Chapter 4. In Chapter 5, the concept of the storage systems is depicted, and the economical feasibility of the systems is evaluated. The concluding remarks are summarized in Chapter 6. (author)

  3. Analysis of electrical and thermal stress effects on PCBM:P3HT solar cells by photocurrent and impedance spectroscopy modeling

    DEFF Research Database (Denmark)

    Torto, Lorenzo; Rizzo, Antonio; Cester, Andrea

    2017-01-01

    We investigated the effects of electrical stress and thermal storage by means of photocurrent, Impedance Spectroscopy and Open Circuit Voltage Decay models. The electrical stress damages only the active layer, by reducing the generation rate, the polaron separation probability and the carrier...... lifetime. The thermal stress also degrades the anode interface. This reflects on the appearance of an inflection in the I-V photocurrent shape close to the operative region....

  4. Incorporating Water Boiling in the Numerical Modelling of Thermal Remediation by Electrical Resistance Heating

    Science.gov (United States)

    Molnar, I. L.; Krol, M.; Mumford, K. G.

    2017-12-01

    Developing numerical models for subsurface thermal remediation techniques - such as Electrical Resistive Heating (ERH) - that include multiphase processes such as in-situ water boiling, gas production and recovery has remained a significant challenge. These subsurface gas generation and recovery processes are driven by physical phenomena such as discrete and unstable gas (bubble) flow as well as water-gas phase mass transfer rates during bubble flow. Traditional approaches to multiphase flow modeling soil remain unable to accurately describe these phenomena. However, it has been demonstrated that Macroscopic Invasion Percolation (MIP) can successfully simulate discrete and unstable gas transport1. This has lead to the development of a coupled Electro Thermal-MIP Model2 (ET-MIP) capable of simulating multiple key processes in the thermal remediation and gas recovery process including: electrical heating of soil and groundwater, water flow, geological heterogeneity, heating-induced buoyant flow, water boiling, gas bubble generation and mobilization, contaminant mass transport and removal, and additional mechanisms such as bubble collapse in cooler regions. This study presents the first rigorous validation of a coupled ET-MIP model against two-dimensional water boiling and water/NAPL co-boiling experiments3. Once validated, the model was used to explore the impact of water and co-boiling events and subsequent gas generation and mobilization on ERH's ability to 1) generate, expand and mobilize gas at boiling and NAPL co-boiling temperatures, 2) efficiently strip contaminants from soil during both boiling and co-boiling. In addition, a quantification of the energy losses arising from steam generation during subsurface water boiling was examined with respect to its impact on the efficacy of thermal remediation. While this study specifically targets ERH, the study's focus on examining the fundamental mechanisms driving thermal remediation (e.g., water boiling) renders

  5. Microgrid Control Strategy Utlizing Thermal Energy Storage With Renewable Solar And Wind Power Generation

    Science.gov (United States)

    2016-06-01

    iii Approved for public release; distribution is unlimited MICROGRID CONTROL STRATEGY UTLIZING THERMAL ENERGY STORAGE WITH RENEWABLE SOLAR AND WIND... control tracks increasing power generation in the morning. The batteries require a large amount of electrical power to charge every morning, as charge ...is 37 lost throughout the night. This causes the solar panels to output their maximum power generation. The MPPT control records when power

  6. A research on thermoelectric generator's electrical performance under temperature mismatch conditions for automotive waste heat recovery system

    Directory of Open Access Journals (Sweden)

    Z.B. Tang

    2015-03-01

    Full Text Available The thermoelectric generators recover useful energy by the function of thermoelectric modules which can convert waste heat energy into electricity from automotive exhaust. In the actual operation, the electrical connected thermoelectric modules are operated under temperature mismatch conditions and then the problem of decreased power output causes due to the inhomogeneous temperature gradient distribution on heat exchanger surface. In this case study, an individual module test system and a test bench have been carried out to test and analyze the impact of thermal imbalance on the output electrical power at module and system level. Variability of the temperature difference and clamping pressure are also tested in the individual module measurement. The system level experimental results clearly describe the phenomenon of thermoelectric generator's decreased power output under mismatched temperature condition and limited working temperature. This situation is improved with thermal insulation on the modules and proved to be effective.

  7. Thermal to Electric Energy Conversion for Cyclic Heat Loads

    Science.gov (United States)

    Whitehead, Benjamin E.

    Today, we find cyclic heat loads almost everywhere. When we drive our cars, the engines heat up while we are driving and cool while parked. Processors heat while the computer is in use at the office and cool when idle at night. The sun heats the earth during the day and the earth radiates that heat into space at night. With modern technology, we have access to a number of methods to take that heat and convert it into electricity, but, before selecting one, we need to identify the parameters that inform decision making. The majority of the parameters for most systems include duty cycle, total cost, weight, size, thermal efficiency, and electrical efficiency. However, the importance of each of these will depend on the application. Size and weight take priority in a handheld device, while efficiency dominates in a power plant, and duty cycle is likely to dominate in highly demanding heat pump applications. Over the past decade, developments in semiconductor technology has led to the creation of the thermoelectric generator. With no moving parts and a nearly endlessly scalable nature, these generators present interesting opportunities for taking advantage of any source of waste heat. However, these generators are typically only capable of 5-8% efficiency from conversion of thermal to electric energy. [1]. Similarly, advancements in photovoltaic cells has led to the development of thermophotovoltaics. By heating an emitter to a temperature so it radiates light, a thermophotovoltaic cell then converts that light into electricity. By selecting materials that emit light in the optimal ranges of the appropriate photovoltaic cells, thermophotovoltaic systems can potentially exceed the current maximum of 10% efficiency. [2]. By pressurizing certain metal powders with hydrogen, hydrogen can be bound to the metal, creating a metal hydride, from which hydrogen can be later re-extracted under the correct pressure and temperature conditions. Since this hydriding reaction is

  8. Optimisation of a Kalina cycle for a central receiver solar thermal power plant with direct steam generation

    DEFF Research Database (Denmark)

    Modi, Anish; Haglind, Fredrik

    2014-01-01

    Central receiver solar thermal power plants are regarded as one of the promising ways to generate electricity in near future. They offer the possibility of using high temperatures and pressures to achieve high efficiencies with standard power cycles. A direct steam generation approach can be used...

  9. Artificial Neural Network based control for PV/T panel to track optimum thermal and electrical power

    International Nuclear Information System (INIS)

    Ben Ammar, Majed; Chaabene, Maher; Chtourou, Zied

    2013-01-01

    Highlights: ► We establish a state model of PV/T panel. ► We study the effect of mass flow rate on PV/T efficiency. ► A real time PV/T control algorithm is proposed. ► A model based optimal thermal and electrical power operation point is tracked. - Abstract: As solar energy is intermittent, many algorithms and electronics have been developed to track the maximum power generation from photovoltaic and thermal panels. Following technological advances, these panels are gathered into one unit: PV/T system. PV/T delivers simultaneously two kinds of power: electrical power and thermal power. Nevertheless, no control systems have been developed in order to track maximum power generation from PV/T system. This paper suggests a PV/T control algorithm based on Artificial Neural Network (ANN) to detect the optimal power operating point (OPOP) by considering PV/T model behavior. The OPOP computes the optimum mass flow rate of PV/T for a considered irradiation and ambient temperature. Simulation results demonstrate great concordance between OPOP model based calculation and ANN outputs.

  10. An experimental study on energy generation with a photovoltaic (PV)-solar thermal hybrid system

    International Nuclear Information System (INIS)

    Erdil, Erzat; Ilkan, Mustafa; Egelioglu, Fuat

    2008-01-01

    A hybrid system, composed of a photovoltaic (PV) module and a solar thermal collector is constructed and tested for energy collection at a geographic location of Cyprus. Normally, it is required to install a PV system occupying an area of about 10 m 2 in order to produce electrical energy; 7 kWh/day, required by a typical household. In this experimental study, we used only two PV modules of area approximately 0.6 m 2 (i.e., 1.3x0.47 m 2 ) each. PV modules absorb a considerable amount of solar radiation that generate undesirable heat. This thermal energy, however, may be utilized in water pre-heating applications. The proposed hybrid system produces about 2.8 kWh thermal energy daily. Various attachments that are placed over the hybrid modules lead to a total of 11.5% loss in electrical energy generation. This loss, however, represents only 1% of the 7 kWh energy that is consumed by a typical household in northern Cyprus. The pay-back period for the modification is less than 2 years. The low investment cost and the relatively short pay-back period make this hybrid system economically attractive

  11. Thermal and electrical conductivities of high purity tantalum

    International Nuclear Information System (INIS)

    Archer, S.L.

    1978-01-01

    The electrical resistivity and thermal conductivity of three high purity tantalum samples have been measured as functions of temperature over a temperature range of 5K to 65K. Sample purities ranged up to a resistivity ratio of 1714. The highest purity sample had a residual resistivity of .76 x 10 -10 OMEGA-m. The intrinsic resistivity varied as T 3 . 9 from 10K to 31K. The thermal conductivity of the purest sample had a maximum of 840 W/mK at 9.8K. The intrinsic thermal resistivity varied as T 2 . 4 from 10K to 35K. At low temperatures electrons were scattered primarily by impurities and by phonons with both interband and intraband transitions observed. The electrical and thermal resistivity is departed from Matthiessen's rule at low temperatures

  12. Stochastic optimal generation bid to electricity markets with emissions risk constraints.

    Science.gov (United States)

    Heredia, F-Javier; Cifuentes-Rubiano, Julián; Corchero, Cristina

    2018-02-01

    There are many factors that influence the day-ahead market bidding strategies of a generation company (GenCo) within the framework of the current energy market. Environmental policy issues are giving rise to emission limitation that are becoming more and more important for fossil-fueled power plants, and these must be considered in their management. This work investigates the influence of the emissions reduction plan and the incorporation of the medium-term derivative commitments in the optimal generation bidding strategy for the day-ahead electricity market. Two different technologies have been considered: the high-emission technology of thermal coal units and the low-emission technology of combined cycle gas turbine units. The Iberian Electricity Market (MIBEL) and the Spanish National Emissions Reduction Plan (NERP) defines the environmental framework for dealing with the day-ahead market bidding strategies. To address emission limitations, we have extended some of the standard risk management methodologies developed for financial markets, such as Value-at-Risk (VaR) and Conditional Value-at-Risk (CVaR), thus leading to the new concept of Conditional Emission at Risk (CEaR). This study offers electricity generation utilities a mathematical model for determining the unit's optimal generation bid to the wholesale electricity market such that it maximizes the long-term profits of the utility while allowing it to abide by the Iberian Electricity Market rules as well as the environmental restrictions set by the Spanish National Emissions Reduction Plan. We analyze the economic implications for a GenCo that includes the environmental restrictions of this National Plan as well as the NERP's effects on the expected profits and the optimal generation bid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Electricity market opening and electricity generation system's expansion in Slovenia

    International Nuclear Information System (INIS)

    Kosnjek, Z.; Vidmar, M.; Bregar, Z.

    2000-01-01

    Slovenia is rapidly adopting the European Union (EU) legislation to make itself ready to be admitted the fifteen EU member countries. In the area of energy or electricity supply industry, Slovenia has consequently enforced the Energy law, which in its essence follows the idea of the Directive 96/92/EC. Globally, the Directive defines common rules of the internal electricity market within EU. Any EU member country is responsible for assuring a competitive electricity market and implementing corresponding instruments as foreseen by the Directive. The share of the national market opening is calculated on the basis of eligible customers' consumption versus the overall consumption in a particular member country. Also, the Directive defines the rate of the electricity market opening. It is interesting to note that the EU member countries have been opening their national electricity markets at a greater speed than specified by the Directive. The overall Slovenian Electricity Supply Industry shall have to adapt itself to new imperatives, whereby the greatest changes will by all means take place in the area of electricity generation. As the reaction of eligible domestic market customers is quite unpredictable, the direct electricity import from foreign countries can only be estimated on a variant basis. EU countries that have deregulated their electricity market have been, step by step, gaining valuable experiences. The majority of them show a considerable pressure on having prices of the EPS generation sector reduced. A similar development can by all means be expected in Slovenia, too. it is expected that the major burden of the electricity market liberalisation and electric power interconnecting within EU will be carried by the EPS generation sector. The analyses of developed variants show that the burden, imposed by the transition onto the market economy, will be predominantly carried by the coal fired electricity supply industry. Further development of electricity

  14. Strategies and options for electricity generation in Egypt up to 2020

    International Nuclear Information System (INIS)

    Yassin, I. M.; Megahed, M. M.; Motayasser, S. S.

    2004-01-01

    Over the period 1970-2000, the total primary energy requirements in Egypt have increased from 7.8 million tones of oil equivalent (Mtoe) to 44.2 Mtoe. In the same period, electricity generation has increased from 6.7 TWh to 73.3 TWh. The demand for both primary energy and electricity is expected to continue at higher growth rates in the future due to the ambitious governmental plans aiming at increasing the gross domestic product (GDP) at an average annual growth rate of 8% up to the year 2020. Because of the limited fossil fuel energy resources and the almost fully utilized hydro energy, Egypt has been considering for sometime the various options for satisfying the increasing demand for electricity, including nuclear energy. To this end, the Nuclear Power Plants Authority carried out a comparative study of the various strategies and options for electricity generation in Egypt with technical assistance from the International Atomic Energy Agency (IAEA) utilizing the DECADES Tool. The main objective of the study was to determine the optimal electricity generation mix up to the year 2020, including nuclear and renewable (solar and wind) energies. DECADES is restricted by some limitation that it did not take into its consideration modeling of some energy forms and systems such as simulation of Renewable Energy Options (REO), in particular thermal/solar and wind plants and simulation of Independent Power Producers (IPP). REO and IPP, as well as the nuclear energy option are expected to play an important role in the future electricity generation mix in Egypt. Therefore it is important to consider its effects economically and environmentally when studying the best expansion system in Egypt. This paper presents the modifications for DECADES modeling to enable simulation for the above energy forms and systems, as well as the results of the comparative assessment study.(author)

  15. Electricity generation in the world and Ukraine: Current status and future developments

    Directory of Open Access Journals (Sweden)

    Alexander Zvorykin

    2017-11-01

    Full Text Available Electricity generation is the key factor for advances in industry, agriculture, technology and the level of living. Also, strong power industry with diverse energy sources is very important for country independence. In general, electricity can be generated from: 1 non-renewable energy sources such as coal, natural gas, oil, and nuclear; and 2 renewable energy sources such as hydro, biomass, wind, geothermal, solar, and wave power. However, the major energy sources for electricity generation in the world are: 1 thermal power – primarily using coal (~40% and secondarily natural gas (~23%; 2 “large” hydro power plants (~17% and 3 nuclear power from various reactor designs (~11%. The rest of the energy sources for electricity generation is from using oil (~4% and renewable sources such as biomass, wind, geothermal and solar (~5%, which have just visible impact in selected countries. In addition, energy sources, such as wind and solar, and some others, like tidal and wave-power, are intermittent from depending on Mother Nature. And cannot be used alone for industrial electricity generation. Nuclear power in Ukraine is the most important source of electricity generation in the country. Currently, Ukrainian Nuclear Power Plants (NPPs generate about 45.5% of the total electricity followed with coal generation ‒ 38%, gas generation 9.6% and the rest is based on renewable sources, mainly on hydro power plants – 5.9%. Nuclear-power industry is based on four NPPs (15 Pressurized Water Reactors (PWRs including the largest one in Europe ‒ Zaporizhzhya NPP with about 6,000 MWel gross installed capacity. Two of these 15 reactors have been built and put into operation in 70-s, ten in 80-s, one in 90-s and just two in 2004. Therefore, based on an analysis of the world power reactors in terms of their maximum years of operation (currently, the oldest reactors are ~45-year old several projections have been made for future of the nuclear-power industry

  16. Solar electric power generation photovoltaic energy systems

    CERN Document Server

    Krauter, Stefan CW

    2007-01-01

    Solar electricity is a viable, environmentally sustainable alternative to the world's energy supplies. In support, this work examines the various technical parameters of photovoltaic systems. It analyzes the study of performance and yield (including optical, thermal, and electrical parameters and interfaces).

  17. Quasi-Static Electric Field Generator

    Science.gov (United States)

    Generazio, Edward R. (Inventor)

    2017-01-01

    A generator for producing an electric field for with an inspection technology system is provided. The generator provides the required variable magnitude quasi-static electric fields for the "illumination" of objects, areas and volumes to be inspected by the system, and produces human-safe electric fields that are only visible to the system. The generator includes a casing, a driven, non-conducting and triboelectrically neutral rotation shaft mounted therein, an ungrounded electrostatic dipole element which works in the quasi-static range, and a non-conducting support for mounting the dipole element to the shaft. The dipole element has a wireless motor system and a charging system which are wholly contained within the dipole element and the support that uses an electrostatic approach to charge the dipole element.

  18. Study of the electrical and thermal performances of photovoltaic thermal collector-compound parabolic concentrated

    Directory of Open Access Journals (Sweden)

    Ahed Hameed Jaaz

    2018-06-01

    Full Text Available The importance of utilizing the solar energy as a very suitable source among multi-source approaches to replace the conventional energy is on the rise in the last four decades. The invention of the photovoltaic module (PV could be the corner stone in this process. However, the limited amount of energy obtained from PV was and still the main challenge of full utilization of the solar energy. In this paper, the use of the compound parabolic concentrator (CPC along with the thermal photovoltaic module (PVT where the cooling process of the CPC is conducted using a novel technique of water jet impingement has applied experimentally and physically tested. The test includes the effect of water jet impingement on the total power, electrical efficiency, thermal efficiency, and total efficiency on CPC-PVT system. The cooling process at the maximum irradiation by water jet impingement resulted in improving the electrical efficiency by 7%, total output power by 31% and the thermal efficiency by 81%. These results outperform the recent highest results recorded by the most recent work. Keywords: Photovoltaic thermal collectors, Electrical performance, Thermal performance, Compound parabolic concentrator, Jet impingement

  19. Novel thermal management system using boiling cooling for high-powered lithium-ion battery packs for hybrid electric vehicles

    Science.gov (United States)

    Al-Zareer, Maan; Dincer, Ibrahim; Rosen, Marc A.

    2017-09-01

    A thermal management system is necessary to control the operating temperature of the lithium ion batteries in battery packs for electrical and hybrid electrical vehicles. This paper proposes a new battery thermal management system based on one type of phase change material for the battery packs in hybrid electrical vehicles and develops a three dimensional electrochemical thermal model. The temperature distributions of the batteries are investigated under various operating conditions for comparative evaluations. The proposed system boils liquid propane to remove the heat generated by the batteries, and the propane vapor is used to cool the part of the battery that is not covered with liquid propane. The effect on the thermal behavior of the battery pack of the height of the liquid propane inside the battery pack, relative to the height of the battery, is analyzed. The results show that the propane based thermal management system provides good cooling control of the temperature of the batteries under high and continuous charge and discharge cycles at 7.5C.

  20. Economic and Environmental Considerations for Zero-emission Transport and Thermal Energy Generation on an Energy Autonomous Island

    Directory of Open Access Journals (Sweden)

    Fontina Petrakopoulou

    2018-01-01

    Full Text Available The high cost and environmental impact of fossil-fuel energy generation in remote regions can make renewable energy applications more competitive than business-as-usual scenarios. Furthermore, energy and transport are two of the main sectors that significantly contribute to global greenhouse gas emissions. This paper focuses on the generation of thermal energy and the transport sector of a fossil fuel-based energy independent island in Greece. We evaluate (1 technologies for fully renewable thermal energy generation using building-specific solar thermal systems and (2 the replacement of the vehicle fleet of the island with electric and hydrogen-fueled vehicles. The analysis, based on economic and environmental criteria, shows that although solar thermal decreases greenhouse gases by 83%, when compared to the current diesel-based situation, it only becomes economically attractive with subsidy scenarios equal to or higher than 50%. However, in the transport sector, the sum of fuel and maintenance costs of fuel-cell and electric vehicles is found to be 45% lower than that of the current fleet, due to their approximately seven times lower fuel cost. Lastly, it will take approximately six years of use of the new vehicles to balance out the emissions of their manufacturing phase.

  1. D Surface Generation from Aerial Thermal Imagery

    Science.gov (United States)

    Khodaei, B.; Samadzadegan, F.; Dadras Javan, F.; Hasani, H.

    2015-12-01

    Aerial thermal imagery has been recently applied to quantitative analysis of several scenes. For the mapping purpose based on aerial thermal imagery, high accuracy photogrammetric process is necessary. However, due to low geometric resolution and low contrast of thermal imaging sensors, there are some challenges in precise 3D measurement of objects. In this paper the potential of thermal video in 3D surface generation is evaluated. In the pre-processing step, thermal camera is geometrically calibrated using a calibration grid based on emissivity differences between the background and the targets. Then, Digital Surface Model (DSM) generation from thermal video imagery is performed in four steps. Initially, frames are extracted from video, then tie points are generated by Scale-Invariant Feature Transform (SIFT) algorithm. Bundle adjustment is then applied and the camera position and orientation parameters are determined. Finally, multi-resolution dense image matching algorithm is used to create 3D point cloud of the scene. Potential of the proposed method is evaluated based on thermal imaging cover an industrial area. The thermal camera has 640×480 Uncooled Focal Plane Array (UFPA) sensor, equipped with a 25 mm lens which mounted in the Unmanned Aerial Vehicle (UAV). The obtained results show the comparable accuracy of 3D model generated based on thermal images with respect to DSM generated from visible images, however thermal based DSM is somehow smoother with lower level of texture. Comparing the generated DSM with the 9 measured GCPs in the area shows the Root Mean Square Error (RMSE) value is smaller than 5 decimetres in both X and Y directions and 1.6 meters for the Z direction.

  2. Electric vehicle charge patterns and the electricity generation mix and competitiveness of next generation vehicles

    International Nuclear Information System (INIS)

    Masuta, Taisuke; Murata, Akinobu; Endo, Eiichi

    2014-01-01

    Highlights: • The energy system of whole of Japan is analyzed in this study. • An advanced model based on MARKAL is used for the energy system analysis. • The impact of charge patterns of EVs on electricity generation mix is evaluated. • Technology competitiveness of the next generation vehicles is also evaluated. - Abstract: The nuclear accident of 2011 brought about a reconsideration of the future electricity generation mix of power systems in Japan. A debate on whether to phase out nuclear power plants and replace them with renewable energy sources is taking place. Demand-side management becomes increasingly important in future Japanese power systems with a large-scale integration of renewable energy sources. This paper considers the charge control of electric vehicles (EVs) through demand-side management. There have been many studies of the control or operation methods of EVs known as vehicle-to-grid (V2G), and it is important to evaluate both their short-term and long-term operation. In this study, we employ energy system to evaluate the impact of the charge patterns of EVs on both the electricity generation mix and the technology competitiveness of the next generation vehicles. An advanced energy system model based on Market Allocation (MARKAL) is used to consider power system control in detail

  3. Electrical and thermal properties of graphite/polyaniline composites

    Energy Technology Data Exchange (ETDEWEB)

    Bourdo, Shawn E., E-mail: sxbourdo@ualr.edu [Center for Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204 (United States); Warford, Brock A.; Viswanathan, Tito [Department of Chemistry, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204 (United States)

    2012-12-15

    A composite of a carbon allotrope (graphite) and an inherently conducting polymer, polyaniline (PANI), has been prepared that exhibits an electrical conductivity greater than either of the two components. An almost 2-fold increase in the bulk conductivity occurs when only a small mass fraction of polyaniline exists in the composite (91% graphite/ 9% polyaniline, by mass). This increase in dc electrical conductivity is curious since in most cases a composite material will exhibit a conductivity somewhere between the two individual components, unless a modification to the electronic nature of the material occurs. In order to elucidate the fundamental electrical properties of the composite we have performed variable temperature conductivity measurements to better understand the nature of conduction in these materials. The results from these studies suggest a change in the mechanism of conduction as the amount of polyaniline is increased in the composite. Along with superior electrical properties, the composites exhibit an increase in thermal stability as compared to the graphite. - Graphical abstract: (Left) Room temperature electrical conductivity of G-PANI composites at different mass ratios. (Right) Electrical conductivity of G-PANI composites at temperatures from 5 K to 300 K. Highlights: Black-Right-Pointing-Pointer Composites of graphite and polyaniline have been synthesized with unique electrical and thermal properties. Black-Right-Pointing-Pointer Certain G-PANI composites are more conductive and more thermally stable than graphite alone. Black-Right-Pointing-Pointer G-PANI composites exhibit a larger conductivity ratio with respect to temperature than graphite alone.

  4. Meeting residential space heating demand with wind-generated electricity

    International Nuclear Information System (INIS)

    Hughes, Larry

    2010-01-01

    Worldwide, many electricity suppliers are faced with the challenge of trying to integrate intermittent renewables, notably wind, into their energy mix to meet the needs of those services that require a continuous supply of electricity. Solutions to intermittency include the use of rapid-response backup generation and chemical or mechanical storage of electricity. Meanwhile, in many jurisdictions with lengthy heating seasons, finding secure and preferably environmentally benign supplies of energy for space heating is also becoming a significant challenge because of volatile energy markets. Most, if not all, electricity suppliers treat these twin challenges as separate issues: supply (integrating intermittent renewables) and demand (electric space heating). However, if space heating demand can be met from an intermittent supply of electricity, then both of these issues can be addressed simultaneously. One such approach is to use off-the-shelf electric thermal storage systems. This paper examines the potential of this approach by applying the output from a 5.15 MW wind farm to the residential heating demands of detached households in the Canadian province of Prince Edward Island. The paper shows that for the heating season considered, up to 500 households could have over 95 percent of their space heating demand met from the wind farm in question. The benefits as well as the limitations of the approach are discussed in detail. (author)

  5. Entropy generation method to quantify thermal comfort

    Science.gov (United States)

    Boregowda, S. C.; Tiwari, S. N.; Chaturvedi, S. K.

    2001-01-01

    The present paper presents a thermodynamic approach to assess the quality of human-thermal environment interaction and quantify thermal comfort. The approach involves development of entropy generation term by applying second law of thermodynamics to the combined human-environment system. The entropy generation term combines both human thermal physiological responses and thermal environmental variables to provide an objective measure of thermal comfort. The original concepts and definitions form the basis for establishing the mathematical relationship between thermal comfort and entropy generation term. As a result of logic and deterministic approach, an Objective Thermal Comfort Index (OTCI) is defined and established as a function of entropy generation. In order to verify the entropy-based thermal comfort model, human thermal physiological responses due to changes in ambient conditions are simulated using a well established and validated human thermal model developed at the Institute of Environmental Research of Kansas State University (KSU). The finite element based KSU human thermal computer model is being utilized as a "Computational Environmental Chamber" to conduct series of simulations to examine the human thermal responses to different environmental conditions. The output from the simulation, which include human thermal responses and input data consisting of environmental conditions are fed into the thermal comfort model. Continuous monitoring of thermal comfort in comfortable and extreme environmental conditions is demonstrated. The Objective Thermal Comfort values obtained from the entropy-based model are validated against regression based Predicted Mean Vote (PMV) values. Using the corresponding air temperatures and vapor pressures that were used in the computer simulation in the regression equation generates the PMV values. The preliminary results indicate that the OTCI and PMV values correlate well under ideal conditions. However, an experimental study

  6. Effective electrical and thermal conductivity of multifilament twisted superconductors

    International Nuclear Information System (INIS)

    Chechetkin, V.R.

    2013-01-01

    The effective electrical and thermal conductivity of composite wire with twisted superconducting filaments embedded into normal metal matrix is calculated using the extension of Bruggeman method. The resistive conductivity of superconducting filaments is described in terms of symmetric tensor, whereas the conductivity of a matrix is assumed to be isotropic and homogeneous. The dependence of the resistive electrical conductivity of superconducting filaments on temperature, magnetic field, and current density is implied to be parametric. The resulting effective conductivity tensor proved to be non-diagonal and symmetric. The non-diagonal transverse–longitudinal components of effective electrical conductivity tensor are responsible for the redistribution of current between filaments. In the limits of high and low electrical conductivity of filaments the transverse effective conductivity tends to that of obtained previously by Carr. The effective thermal conductivity of composite wires is non-diagonal and radius-dependent even for the isotropic and homogeneous thermal conductivities of matrix and filaments.

  7. Thermal Management of Power Electronics and Electric Motors for Electric-Drive Vehicles (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, S.

    2014-09-01

    This presentation is an overview of the power electronics and electric motor thermal management and reliability activities at NREL. The focus is on activities funded by the Department of Energy Vehicle Technologies Office Advanced Power Electronics and Electric Motors Program.

  8. Thermo-optically tuned photonic resonators with concurrent electrical connection and thermal isolation

    Science.gov (United States)

    Lentine, Anthony L.; Kekatpure, Rohan Deodatta; Zortman, William A.; Savignon, Daniel J.

    2016-06-14

    A photonic resonator system is designed to use thermal tuning to adjust the resonant wavelength of each resonator in the system, with a separate tuning circuit associated with each resonator so that individual adjustments may be made. The common electrical ground connection between the tuning circuits is particularly formed to provide thermal isolation between adjacent resonators by including a capacitor along each return path to ground, where the presence of the capacitor's dielectric material provides the thermal isolation. The use of capacitively coupling necessarily requires the use of an AC current as an input to the heater element (conductor/resistor) of each resonator, where the RMS value of the AC signal is indicative of the amount of heat that is generated along the element and the degree of wavelength tuning that is obtained.

  9. Stand alone solution for generation and storage of hydrogen and electric energy

    International Nuclear Information System (INIS)

    Gany, Alon; Elitzur, Shani; Valery

    2015-01-01

    A novel method enabling safe, simple, and controllable production, storage, and use of hydrogen as well as compact electric energy storage and generation via hydrogen- oxygen fuel cells has been developed. The technology indicates, in our opinion, a significant milestone in the search for practical utilization of hydrogen as an alternative energy source. It consists of an original thermal-chemical treatment / activation of aluminum powders to react spontaneously with water to produce hydrogen at regular conditions according to the reaction Al+3H 2 O=Al (OH) 3 +3/2H 2 . Only about 1-2% of lithium, based activator is applied, and any type of water including tap water, sea water and waste water may be used, making the method attractive for variety of applications. 11% of hydrogen compared to the aluminum mass can be obtained, and our experiments reveal 90% reaction yield and more. The technology has a clear advantage over batteries, providing specific electric energy of over 2 kW h/kg Al, 5-10 times greater than that of commonly used lithium-ion batteries. Combined with a fuel cell it may be particularly beneficial for stand-alone electric power generators, where there is no access to the grid. Such applications include emergency generators (e.g., in hospitals), electricity backup systems, and power generation in remote communication posts. Automotive applications may be considered as well. The technology provides green electric energy and quiet operation as well as additional heat energy resulting mainly from the exothermic aluminum-water reaction. (full text)

  10. Realistic generation cost of solar photovoltaic electricity

    International Nuclear Information System (INIS)

    Singh, Parm Pal; Singh, Sukhmeet

    2010-01-01

    Solar photovoltaic (SPV) power plants have long working life with zero fuel cost and negligible maintenance cost but requires huge initial investment. The generation cost of the solar electricity is mainly the cost of financing the initial investment. Therefore, the generation cost of solar electricity in different years depends on the method of returning the loan. Currently levelized cost based on equated payment loan is being used. The static levelized generation cost of solar electricity is compared with the current value of variable generation cost of grid electricity. This improper cost comparison is inhibiting the growth of SPV electricity by creating wrong perception that solar electricity is very expensive. In this paper a new method of loan repayment has been developed resulting in generation cost of SPV electricity that increases with time like that of grid electricity. A generalized capital recovery factor has been developed for graduated payment loan in which capital and interest payment in each installment are calculated by treating each loan installment as an independent loan for the relevant years. Generalized results have been calculated which can be used to determine the cost of SPV electricity for a given system at different places. Results show that for SPV system with specific initial investment of 5.00 cents /kWh/year, loan period of 30 years and loan interest rate of 4% the levelized generation cost of SPV electricity with equated payment loan turns out to be 28.92 cents /kWh, while the corresponding generation cost with graduated payment loan with escalation in annual installment of 8% varies from 9.51 cents /kWh in base year to 88.63 cents /kWh in 30th year. So, in this case, the realistic current generation cost of SPV electricity is 9.51 cents /kWh and not 28.92 cents /kWh. Further, with graduated payment loan, extension in loan period results in sharp decline in cost of SPV electricity in base year. Hence, a policy change is required

  11. Simulation of thermal stresses in anode-supported solid oxide fuel cell stacks. Part II: Loss of gas-tightness, electrical contact and thermal buckling

    Science.gov (United States)

    Nakajo, Arata; Wuillemin, Zacharie; Van herle, Jan; Favrat, Daniel

    Structural stability issues in planar solid oxide fuel cells arise from the mismatch between the coefficients of thermal expansion of the components. The stress state at operating temperature is the superposition of several contributions, which differ depending on the component. First, the cells accumulate residual stresses due to the sintering phase during the manufacturing process. Further, the load applied during assembly of the stack to ensure electric contact and flatten the cells prevents a completely stress-free expansion of each component during the heat-up. Finally, thermal gradients cause additional stresses in operation. The temperature profile generated by a thermo-electrochemical model implemented in an equation-oriented process modelling tool (gPROMS) was imported into finite-element software (ABAQUS) to calculate the distribution of stress and contact pressure on all components of a standard solid oxide fuel cell repeat unit. The different layers of the cell in exception of the cathode, i.e. anode, electrolyte and compensating layer were considered in the analysis to account for the cell curvature. Both steady-state and dynamic simulations were performed, with an emphasis on the cycling of the electrical load. The study includes two different types of cell, operation under both thermal partial oxidation and internal steam-methane reforming and two different initial thicknesses of the air and fuel compressive sealing gaskets. The results generated by the models are presented in two papers: Part I focuses on cell cracking. In the present paper, Part II, the occurrences of loss of gas-tightness in the compressive gaskets and/or electrical contact in the gas diffusion layer were identified. In addition, the dependence on temperature of both coefficients of thermal expansion and Young's modulus of the metallic interconnect (MIC) were implemented in the finite-element model to compute the plastic deformation, while the possibilities of thermal buckling

  12. Analytical thermal model validation for Cassini radioisotope thermoelectric generator

    International Nuclear Information System (INIS)

    Lin, E.I.

    1997-01-01

    The Saturn-bound Cassini spacecraft is designed to rely, without precedent, on the waste heat from its three radioisotope thermoelectric generators (RTGs) to warm the propulsion module subsystem, and the RTG end dome temperature is a key determining factor of the amount of waste heat delivered. A previously validated SINDA thermal model of the RTG was the sole guide to understanding its complex thermal behavior, but displayed large discrepancies against some initial thermal development test data. A careful revalidation effort led to significant modifications and adjustments of the model, which result in a doubling of the radiative heat transfer from the heat source support assemblies to the end domes and bring up the end dome and flange temperature predictions to within 2 C of the pertinent test data. The increased inboard end dome temperature has a considerable impact on thermal control of the spacecraft central body. The validation process offers an example of physically-driven analytical model calibration with test data from not only an electrical simulator but also a nuclear-fueled flight unit, and has established the end dome temperatures of a flight RTG where no in-flight or ground-test data existed before

  13. Experimental Evaluation of Simple Thermal Storage Control Strategies in Low-Energy Solar Houses to Reduce Electricity Consumption during Grid On-Peak Periods

    Directory of Open Access Journals (Sweden)

    Kyoung-Ho Lee

    2015-08-01

    Full Text Available There is growing interest in zero-energy and low-energy buildings, which have a net energy consumption (on an annual basis of almost zero. Because they can generate both electricity and thermal energy through the use of solar photovoltaic (PV and solar thermal collectors, and with the help of reduced building thermal demand, low-energy buildings can not only make a significant contribution to energy conservation on an annual basis, but also reduce energy consumption and peak demand. This study focused on electricity consumption during the on-peak period in a low-energy residential solar building and considers the use of a building’s thermal mass and thermal storage to reduce electricity consumption in summer and winter by modulation of temperature setpoints for heat pump and indoor thermostats in summer and additional use of a solar heating loop in winter. Experiments were performed at a low-energy solar demonstration house that has solar collectors, hot water storage, a ground-coupled heat pump, and a thermal storage tank. It was assumed that the on-peak periods were from 2 pm to 5 pm on hot summer days and from 5 pm to 8 pm on cold winter days. To evaluate the potential for utilizing the building’s thermal storage capacity in space cooling and heating, the use of simple control strategies on three test days in summer and two test days in the early spring were compared in terms of net electricity consumption and peak demand, which also considered the electricity generation from solar PV modules on the roof of the house.

  14. Comparison based on energy and exergy analyses of the potential cogeneration efficiencies for fuel cells and other electricity generation devices

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, M A [Ryerson Polytechnical Inst., Toronto, (CA). Dept. of Mechanical Engineering

    1990-01-01

    Comparisons of the potential cogeneration efficiencies are made, based on energy and exergy analyses, for several devices for electricity generation. The investigation considers several types of fuel cell system (Phosphoric Acid, Alkaline, Solid Polymer Electrolyte, Molten Carbonate and Solid Oxide), and several fossil-fuel and nuclear cogeneration systems based on steam power plants. In the analysis, each system is modelled as a device for which fuel and air enter, and electrical- and thermal-energy products and material and thermal-energy wastes exit. The results for all systems considered indicate that exergy analyses should be used when analysing the cogeneration potential of systems for electricity generation, because they weigh the usefulnesses of heat and electricity on equivalent bases. Energy analyses tend to present overly optimistic views of performance. These findings are particularly significant when large fractions of the heat output from a system are utilized for cogeneration. (author).

  15. Convective Heat Transfer Coefficients of Automatic Transmission Fluid Jets with Implications for Electric Machine Thermal Management: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Bennion, Kevin; Moreno, Gilberto

    2015-09-29

    Thermal management for electric machines (motors/ generators) is important as the automotive industry continues to transition to more electrically dominant vehicle propulsion systems. Cooling of the electric machine(s) in some electric vehicle traction drive applications is accomplished by impinging automatic transmission fluid (ATF) jets onto the machine's copper windings. In this study, we provide the results of experiments characterizing the thermal performance of ATF jets on surfaces representative of windings, using Ford's Mercon LV ATF. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients. Fluid temperatures were varied from 50 degrees C to 90 degrees C to encompass potential operating temperatures within an automotive transaxle environment. The jet nozzle velocities were varied from 0.5 to 10 m/s. The experimental ATF heat transfer coefficient results provided in this report are a useful resource for understanding factors that influence the performance of ATF-based cooling systems for electric machines.

  16. Electrical and thermal characteristics of Bi2212/Ag HTS coils for conduction-cooled SMES

    International Nuclear Information System (INIS)

    Hayakawa, N; Noguchi, S; Kurupakorn, C; Kojima, H; Endo, F; Hirano, N; Nagaya, S; Okubo, H

    2006-01-01

    In this paper, we investigated the electrical and thermal performance of conduction-cooled Bi2212/Ag HTS coils with 4K-GM cryocooler system. First, we measured the critical current I c for different ambient temperatures T 0 at 4.2 K - 40 K. Experimental results revealed that I c increased with the decrease in T 0 and was saturated at T 0 0 = 4.8 K. Experimental results revealed the criterion of thermal runaway, which was discussed in terms of heat generation and propagation in the test coil

  17. Feeble magnetic fields generated by thermal charge fluctuations in extended metallic conductors: Implications for electric-dipole moment experiments

    International Nuclear Information System (INIS)

    Lamoreaux, S.K.

    1999-01-01

    A simple formulation for calculating the magnetic field external to an extended nonpermeable conducting body due to thermal current fluctuations within the body is developed, and is applied to a recent experimental search for the atomic electric-dipole moment (EDM) of 199 Hg. It is shown that the thermal fluctuation field is only slightly smaller in magnitude than other noise sources in that experiment. The formulation is extended to permeable bodies, and the implications for general EDM experiments are discussed. copyright 1999 The American Physical Society

  18. Static and dynamic high power, space nuclear electric generating systems

    International Nuclear Information System (INIS)

    Wetch, J.R.; Begg, L.L.; Koester, J.K.

    1985-01-01

    Space nuclear electric generating systems concepts have been assessed for their potential in satisfying future spacecraft high power (several megawatt) requirements. Conceptual designs have been prepared for reactor power systems using the most promising static (thermionic) and the most promising dynamic conversion processes. Component and system layouts, along with system mass and envelope requirements have been made. Key development problems have been identified and the impact of the conversion process selection upon thermal management and upon system and vehicle configuration is addressed. 10 references

  19. Clean Energy Technologies: A Preliminary Inventory of the Potential for Electricity Generation

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, Owen; Worrell, Ernst

    2005-08-03

    The nation's power system is facing a diverse and broad set of challenges. These range from restructuring and increased competitiveness in power production to the need for additional production and distribution capacity to meet demand growth, and demands for increased quality and reliability of power and power supply. In addition, there are growing concerns about emissions from fossil fuel powered generation units and generators are seeking methods to reduce the CO{sub 2} emission intensity of power generation. Although these challenges may create uncertainty within the financial and electricity supply markets, they also offer the potential to explore new opportunities to support the accelerated deployment of cleaner and cost-effective technologies to meet such challenges. The federal government and various state governments, for example, support the development of a sustainable electricity infrastructure. As part of this policy, there are a variety of programs to support the development of ''cleaner'' technologies such as combined heat and power (CHP, or cogeneration) and renewable energy technologies. Energy from renewable energy sources, such as solar, wind, hydro, and biomass, are considered carbon-neutral energy technologies. The production of renewable energy creates no incremental increase in fossil fuel consumption and CO{sub 2} emissions. Electricity and thermal energy production from all renewable resources, except biomass, produces no incremental increase in air pollutants such as nitrogen oxides, sulfur oxides, particulate matter, and carbon monoxide. There are many more opportunities for the development of cleaner electricity and thermal energy technologies called ''recycled'' energy. A process using fossil fuels to produce an energy service may have residual energy waste streams that may be recycled into useful energy services. Recycled energy methods would capture energy from sources that would otherwise

  20. Concentrating solar thermal power as a viable alternative in China's electricity supply

    International Nuclear Information System (INIS)

    Chung-Ling Chien, John; Lior, Noam

    2011-01-01

    Study of low-carbon and pollution renewable alternatives for China revealed that concentrating solar thermal (CST) electric power generation was underemphasized in China's renewable energy plan. The analysis shows the competitive viability of CST: (1) China has the key prerequisites to make CST power generation economical including high-quality insolation and appropriate land, (2) CST's proven history, scale, and dispatchability makes it a good utility-scale power option, especially in the economically underdeveloped Western regions, (3) while CST power is currently more expensive than coal-fired electricity on a nominal basis, when costs of externalities are accounted for, CST, at 11.4 US cents/kWh, can become 57% cheaper than scrubbed coal and 29% cheaper than nuclear power, (4) CST power continues dropping in cost due to economies of scale and technological improvements and can potentially realize a levelized electricity cost of around 4 cents/kWh within ten years, (5) it would significantly rise in competitiveness if and when China completes the extensive smart grid for connecting its solar-abundant western regions with the high-demand eastern regions, (6) CST has the potential to positively impact Western China's economy, but proper policy and deal structure must be in place to ensure that the local community shares the benefit. - Highlights: ► We analyze inclusion of concentrating solar thermal (CST) power in China. ► We find that CST needs emphasis in China's renewable energy plan. ► The analysis shows that CST is competitive with coal if externalities are considered. ► We recommend a policy that would develop CST power generation in western regions. ► This would be of significant benefit to Western China's economy and to China.

  1. Projected costs of generating electricity

    International Nuclear Information System (INIS)

    2005-01-01

    Previous editions of Projected Costs of Generating Electricity have served as the reference in this field for energy policy makers, electricity system analysts and energy economists. The study is particularly timely in the light of current discussions of energy policy in many countries. The joint IEA/NEA study provides generation cost estimates for over a hundred power plants that use a variety of fuels and technologies. These include coal-fired, gas-fired, nuclear, hydro, solar and wind plants. Cost estimates are also given for combined heat and power plants that use coal, gas and combustible renewables. Data and information for this study were provided by experts from 19 OECD member countries and 3 non-member countries. The power plants examined in the study use technologies available today and considered by participating countries as candidates for commissioning by 2010-2015 or earlier. Investors and other decision makers will also need to take the full range of other factors into account (such as security of supply, risks and carbon emissions) when selecting an electricity generation technology. The study shows that the competitiveness of alternative generation sources and technologies ultimately depends on many parameters: there is no clear-cut ''winner''. Major issues related to generation costs addressed in the report include: descriptions of state-of-the-art generation technologies; the methodologies for incorporating risk in cost assessments; the impact of carbon emission trading; and how to integrate wind power into the electricity grid. An appendix to the report provides country statements on generation technologies and costs. Previous studies in the series were published in 1983, 1986, 1990, 1993 and 1998. (author)

  2. Improvement of Thermal and Electrical Conductivity of Epoxy/boron Nitride/silver Nanoparticle Composite

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seungyong; Lim, Soonho [Korea Institute of Science and Technology, Wanju (Korea, Republic of)

    2017-06-15

    In this study, we investigated the effect of BN (boron nitride) on the thermal and the electrical conductivity of composites. In case of epoxy/BN composites, the thermal conductivity was increased as the BN contents were increased. Epoxy/AgNP (Ag nanoparticle) nanocomposites exhibited a slight change of thermal conductivity and showed a electrical percolation threshold at 20 vol% of Ag nanoparticles. At the fixed Ag nanoparticle content below the electrical percolation threshold, increasing the amount of BN enhanced the electrical conductivity as well as thermal conductivity for the epoxy/AgNP/BN composites.

  3. Electro-thermal analysis and integration issues of lithium ion battery for electric vehicles

    International Nuclear Information System (INIS)

    Saw, L.H.; Ye, Y.; Tay, A.A.O.

    2014-01-01

    Highlights: • We modeled the electrical and thermal behavior of the Li-ion battery. • We validated the simulation results with experimental studies. • We compared the thermal performance of different size of cylindrical cells. • We investigated the integration issues of cylindrical cells into battery pack. - Abstract: Electrical and thermal characteristics of lithium-ion battery packs in electric vehicles in different operating conditions are important in order to design the battery pack thermal management system. In this work, electrical and thermal behaviors of different size of LiFePO 4 cylindrical cells are investigated under various operating conditions. The simulation results show good agreement with the experimental data under various operating modes. Due to the large thermal resistance of layered active material in a Li-ion cell, the temperature difference in the radial direction is significantly correlated with a diameter of cell and I t -rates. Compared with natural convection, strong forced convection will reduce the temperature uniformity in the cell and accelerate the thermal aging rate. Lastly, integration issues of the cells into a battery pack are discussed from mechanical, electrical, thermal, control and monitoring, manufacturing and maintenance aspects. These issues could impact the performance, cost, driving range and life cycle of the battery pack in electric vehicles

  4. Synthesis, structural and electrical characterizations of thermally ...

    African Journals Online (AJOL)

    Synthesis, structural and electrical characterizations of thermally evaporated Cu 2 SnS 3 thin films. ... The surface profilometer shows that the deposited films are rough. The XRD spectra identified the ... The electrical resistivity of the deposited Cu2SnS3 film is 2.55 x 10-3 Ωcm. The conductivity is in the order of 103 Ω-1cm-1.

  5. Have Market-oriented Reforms Decoupled China’s CO2 Emissions from Total Electricity Generation? An Empirical Analysis

    Directory of Open Access Journals (Sweden)

    Wei Shang

    2016-05-01

    Full Text Available Achieving the decoupling of electric CO2 emissions from total electricity generation is important in ensuring the sustainable socioeconomic development of China. To realize this, China implemented market-oriented reforms to its electric power industry at the beginning of 2003. This study used the Tapio decoupling index, the Laspeyres decomposition algorithm, and decoupling-related data from 1993 to 2012 to evaluate the effect of these reforms. Several conclusions can be drawn based on the empirical analysis. (1 The reforms changed the developmental trend of the decoupling index and facilitated its progress towards strong decoupling. (2 The results forecasted through fitting the curve to the decoupling index indicate that strong decoupling would be realized by 2030. (3 Limiting the manufacturing development and upgrading the generation equipment of the thermal power plants are essential for China to achieve strong decoupling at an early date. (4 China should enhance regulatory pressures and guidance for appropriate investment in thermal power plants to ensure the stable development of the decoupling index. (5 Transactions between multiple participants and electricity price bidding play active roles in the stable development of the decoupling index.

  6. Electric power in Canada 1993

    International Nuclear Information System (INIS)

    1994-01-01

    The electric power industry in Canada in 1993 is reviewed. Items discussed include: the international context of Canadian electricity; regulatory structures; electricity and the environment; electricity consumption; electricity generation; generating capacity and reserve; electricity trade; transmission; electric utility investment and financing; costing and pricing; electricity outlook; demand-side management; and non-utility generation. Information is appended on installed capacity and electrical energy consumption in Canada, installed generating capacity, conventional thermal capacity by principal fuel type, provincial electricity imports and exports, Canadian electricity exports by exporter and importer, generation capacity by type, installed generating capacity expansion in Canada by station, federal environmental standards and guidelines, and prices paid by major electric utilities for non-utility generation. 26 figs., 90 tabs

  7. Electrical and thermal characteristics of Bi2212/Ag HTS coils for conduction-cooled SMES

    Science.gov (United States)

    Hayakawa, N.; Noguchi, S.; Kurupakorn, C.; Kojima, H.; Endo, F.; Hirano, N.; Nagaya, S.; Okubo, H.

    2006-06-01

    In this paper, we investigated the electrical and thermal performance of conduction-cooled Bi2212/Ag HTS coils with 4K-GM cryocooler system. First, we measured the critical current Ic for different ambient temperatures T0 at 4.2 K - 40 K. Experimental results revealed that Ic increased with the decrease in T0 and was saturated at T0 account of temperature dependence of specific heat and thermal conductivity of the materials. We also measured the temperature rise of Bi2212/Ag HTS coil for different continuous current levels at T0 = 4.8 K. Experimental results revealed the criterion of thermal runaway, which was discussed in terms of heat generation and propagation in the test coil.

  8. Physical factors affecting the electrically assisted thermal bitumen recovery

    Energy Technology Data Exchange (ETDEWEB)

    Bogdanov, I.I.; Torres, J.-A.; Kamp, A.M. [CHLOE, University of Pau (France); Corre, B. [CSTJF, Total (France)

    2011-07-01

    In the heavy oil industry, thermal processes are used to enhance oil recovery by increasing the reservoir temperature which results in better oil mobility. Low frequency heating (LFH) is a technology using electrical conductivity of connate water to propagate current between electrodes, thus generating heat in the reservoir through the Joule effect. During the preheating and production periods, many physical factors may affect the LFH process and the aim of this study was to determine which factors affect the process and how, using a particular pattern of electrodes. Simulations were conducted using the CMG Stars reservoir simulator under different configurations, conditions and parameters. Important physical properties and operational conditions affecting the LFH process were determined and results showed that convection heat, bulk electrical conductivity and power distribution can be improved by salt water circulation. This paper highlighted the physical factors affecting LFH efficiency and these findings will be useful for future process design.

  9. Electrical properties of pressure quenched silicon by thermal spraying

    International Nuclear Information System (INIS)

    Tan, S.Y.; Gambino, R.J.; Sampath, S.; Herman, H.

    2007-01-01

    High velocity thermal spray deposition of polycrystalline silicon film onto single crystal substrates, yields metastable high pressure forms of silicon in nanocrystalline form within the deposit. The phases observed in the deposit include hexagonal diamond-Si, R-8, BC-8 and Si-IX. The peculiar attribute of this transformation is that it occurs only on orientation silicon substrate. The silicon deposits containing the high pressure phases display a substantially higher electrical conductivity. The resistivity profile of the silicon deposit containing shock induced metastable silicon phases identified by X-ray diffraction patterns. The density of the pressure induced polymorphic silicon is higher at deposit/substrate interface. A modified two-layer model is presented to explain the resistivity of the deposit impacted by the pressure induced polymorphic silicon generated by the thermal spraying process. The pressure quenched silicon deposits on the p - silicon substrate, with or without metastable phases, display the barrier potential of about 0.72 eV. The measured hall mobility value of pressure quenched silicon deposits is in the range of polycrystalline silicon. The significance of this work lies in the fact that the versatility of thermal spray may enable applications of these high pressure forms of silicon

  10. Future distributed generation: An operational multi-objective optimization model for integrated small scale urban electrical, thermal and gas grids

    International Nuclear Information System (INIS)

    Lo Cascio, Ermanno; Borelli, Davide; Devia, Francesco; Schenone, Corrado

    2017-01-01

    Highlights: • Multi-objective optimization model for retrofitted and integrated natural gas pressure regulation stations. • Comparison of different incentive mechanisms for recovered energy based on the characteristics of preheating process. • Control strategies comparison: performances achieved with optimal control vs. ones obtained by thermal load tracking. - Abstract: A multi-objective optimization model for urban integrated electrical, thermal and gas grids is presented. The main system consists of a retrofitted natural gas pressure regulation station where a turbo-expander allows to recover energy from the process. Here, the natural gas must be preheated in order to avoid methane hydrates. The preheating phase could be based on fossil fuels, renewable or on a thermal mix. Depending on the system configuration, the proposed optimization model enables a proper differentiation based on how the natural gas preheating process is expected to be accomplished. This differentiation is addressed by weighting the electricity produced by the turbo-expander and linking it to proper remuneration tariffs. The effectiveness of the model has been tested on an existing plant located in the city of Genoa. Here, the thermal energy is provided by means of two redundant gas-fired boilers and a cogeneration unit. Furthermore, the whole system is thermally integrated with a district heating network. Numerical simulation results, obtained with the commercial proprietary software Honeywell UniSim Design Suite, have been compared with the optimal solutions achieved. The effectiveness of the model, in terms of economic and environmental performances, is finally quantified. For specific conditions, the model allows achieving an operational costs reduction of about 17% with the respect to thermal-load-tracking control logic.

  11. Influence of thermodynamic properties of a thermo-acoustic emitter on the efficiency of thermal airborne ultrasound generation.

    Science.gov (United States)

    Daschewski, M; Kreutzbruck, M; Prager, J

    2015-12-01

    In this work we experimentally verify the theoretical prediction of the recently published Energy Density Fluctuation Model (EDF-model) of thermo-acoustic sound generation. Particularly, we investigate experimentally the influence of thermal inertia of an electrically conductive film on the efficiency of thermal airborne ultrasound generation predicted by the EDF-model. Unlike widely used theories, the EDF-model predicts that the thermal inertia of the electrically conductive film is a frequency-dependent parameter. Its influence grows non-linearly with the increase of excitation frequency and reduces the efficiency of the ultrasound generation. Thus, this parameter is the major limiting factor for the efficient thermal airborne ultrasound generation in the MHz-range. To verify this theoretical prediction experimentally, five thermo-acoustic emitter samples consisting of Indium-Tin-Oxide (ITO) coatings of different thicknesses (from 65 nm to 1.44 μm) on quartz glass substrates were tested for airborne ultrasound generation in a frequency range from 10 kHz to 800 kHz. For the measurement of thermally generated sound pressures a laser Doppler vibrometer combined with a 12 μm thin polyethylene foil was used as the sound pressure detector. All tested thermo-acoustic emitter samples showed a resonance-free frequency response in the entire tested frequency range. The thermal inertia of the heat producing film acts as a low-pass filter and reduces the generated sound pressure with the increasing excitation frequency and the ITO film thickness. The difference of generated sound pressure levels for samples with 65 nm and 1.44 μm thickness is in the order of about 6 dB at 50 kHz and of about 12 dB at 500 kHz. A comparison of sound pressure levels measured experimentally and those predicted by the EDF-model shows for all tested emitter samples a relative error of less than ±6%. Thus, experimental results confirm the prediction of the EDF-model and show that the model can

  12. An electricity generation planning model incorporating demand response

    International Nuclear Information System (INIS)

    Choi, Dong Gu; Thomas, Valerie M.

    2012-01-01

    Energy policies that aim to reduce carbon emissions and change the mix of electricity generation sources, such as carbon cap-and-trade systems and renewable electricity standards, can affect not only the source of electricity generation, but also the price of electricity and, consequently, demand. We develop an optimization model to determine the lowest cost investment and operation plan for the generating capacity of an electric power system. The model incorporates demand response to price change. In a case study for a U.S. state, we show the price, demand, and generation mix implications of a renewable electricity standard, and of a carbon cap-and-trade policy with and without initial free allocation of carbon allowances. This study shows that both the demand moderating effects and the generation mix changing effects of the policies can be the sources of carbon emissions reductions, and also shows that the share of the sources could differ with different policy designs. The case study provides different results when demand elasticity is excluded, underscoring the importance of incorporating demand response in the evaluation of electricity generation policies. - Highlights: ► We develop an electric power system optimization model including demand elasticity. ► Both renewable electricity and carbon cap-and-trade policies can moderate demand. ► Both policies affect the generation mix, price, and demand for electricity. ► Moderated demand can be a significant source of carbon emission reduction. ► For cap-and-trade policies, initial free allowances change outcomes significantly.

  13. Performance study of thermo-electric generator

    Science.gov (United States)

    Rohit, G.; Manaswini, D.; Kotebavi, Vinod; R, Nagaraja S.

    2017-07-01

    Devices like automobiles, stoves, ovens, boilers, kilns and heaters dissipate large amount of waste heat. Since most of this waste heat goes unused, the efficiency of these devices is drastically reduced. A lot of research is being conducted on the recovery of the waste heat, among which Thermoelectric Generators (TEG) is one of the popular method. TEG is a semiconductor device that produces electric potential difference when a thermal gradient develops on it. This paper deals with the study of performance of a TEG module for different hot surface temperatures. Performance characteristics used here are voltage, current and power developed by the TEG. One side of the TEG was kept on a hot plate where uniform heat flux was supplied to that. And the other side was cooled by supplying cold water. The results show that the output power increases significantly with increase in the temperature of the hot surface.

  14. Electrical conductivity of the thermal dusty plasma under the conditions of a hybrid plasma environment simulation facility

    Science.gov (United States)

    Zhukhovitskii, Dmitry I.; Petrov, Oleg F.; Hyde, Truell W.; Herdrich, Georg; Laufer, Rene; Dropmann, Michael; Matthews, Lorin S.

    2015-05-01

    We discuss the inductively heated plasma generator (IPG) facility in application to the generation of the thermal dusty plasma formed by the positively charged dust particles and the electrons emitted by them. We develop a theoretical model for the calculation of plasma electrical conductivity under typical conditions of the IPG. We show that the electrical conductivity of dusty plasma is defined by collisions with the neutral gas molecules and by the electron number density. The latter is calculated in the approximations of an ideal and strongly coupled particle system and in the regime of weak and strong screening of the particle charge. The maximum attainable electron number density and corresponding maximum plasma electrical conductivity prove to be independent of the particle emissivity. Analysis of available experiments is performed, in particular, of our recent experiment with plasma formed by the combustion products of a propane-air mixture and the CeO2 particles injected into it. A good correlation between the theory and experimental data points to the adequacy of our approach. Our main conclusion is that a level of the electrical conductivity due to the thermal ionization of the dust particles is sufficiently high to compete with that of the potassium-doped plasmas.

  15. Analysis Of ElectricalThermal Coupling Of Induction Machine ...

    African Journals Online (AJOL)

    The interaction of the Electrical and mechanical parts of Electrical machines gives rise to the heating of the machine's constituent parts. This consequently leads to an increase in temperature which if not properly monitored may lead to the breakdown of the machine. This paper therefore presents the Electrical and thermal ...

  16. A One-year, Short-Stay Crewed Mars Mission Using Bimodal Nuclear Thermal Electric Propulsion (BNTEP) - A Preliminary Assessment

    Science.gov (United States)

    Burke, Laura A.; Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2013-01-01

    A crewed mission to Mars poses a signi cant challenge in dealing with the physiolog- ical issues that arise with the crew being exposed to a near zero-gravity environment as well as signi cant solar and galactic radiation for such a long duration. While long sur- face stay missions exceeding 500 days are the ultimate goal for human Mars exploration, short round trip, short surface stay missions could be an important intermediate step that would allow NASA to demonstrate technology as well as study the physiological e ects on the crew. However, for a 1-year round trip mission, the outbound and inbound hy- perbolic velocity at Earth and Mars can be very large resulting in a signi cant propellant requirement for a high thrust system like Nuclear Thermal Propulsion (NTP). Similarly, a low thrust Nuclear Electric Propulsion (NEP) system requires high electrical power lev- els (10 megawatts electric (MWe) or more), plus advanced power conversion technology to achieve the lower speci c mass values needed for such a mission. A Bimodal Nuclear Thermal Electric Propulsion (BNTEP) system is examined here that uses three high thrust Bimodal Nuclear Thermal Rocket (BNTR) engines allowing short departure and capture maneuvers. The engines also generate electrical power that drives a low thrust Electric Propulsion (EP) system used for ecient interplanetary transit. This combined system can help reduce the total launch mass, system and operational requirements that would otherwise be required for equivalent NEP or Solar Electric Propulsion (SEP) mission. The BNTEP system is a hybrid propulsion concept where the BNTR reactors operate in two separate modes. During high-thrust mode operation, each BNTR provides 10's of kilo- Newtons of thrust at reasonably high speci c impulse (Isp) of 900 seconds for impulsive trans-planetary injection and orbital insertion maneuvers. When in power generation / EP mode, the BNTR reactors are coupled to a Brayton power conversion system allowing each

  17. Experimental study of camel powered electricity generation unit

    Science.gov (United States)

    Jakhar, O. P.; Choudhary, Rahul Raj; Budaniya, Mukesh; Kumar, Ashish

    2018-05-01

    Developing nations are facing a huge gap in generation and demand of electricity across the world. In present scenario the demand of electricity is increasing day by day and the shortfall of electricity has become one of the major obstructions in the development of rural areas. There is a big gap between electricity supply and demand. In India it is very difficult that to give twenty four hours electric supply in rural areas. The traditional use of camel as draught animal, for the purpose of transport of goods and agricultural work, has been drastically reduced during last few decades, due to advancements and cheaper availability of mechanical machineries. In this research paper we experimentally studied the camel powered electricity generation system at National Research Centre on Camels (NRCC) Bikaner. Camel Energy in form of high torque low speed can be converted into low torque high speed through motion converting system i.e. gear and pulley mechanism for high RPM output. This high RPM (more than 3000) output is used for electricity generation. The electricity generated can be used directly or stored in the battery and later may be used whenever it is required either for DC light or AC light using inverter. According to experimental study a camel can comfortably generate electricity up to 1KW by rotating shaft. The complete set up for electricity generation using camel power has been designed, developed and physically commissioned at National Research Centre on Camels (NRCC) Bikaner.

  18. Analysis of Large- Capacity Water Heaters in Electric Thermal Storage Programs

    Energy Technology Data Exchange (ETDEWEB)

    Cooke, Alan L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, David M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Winiarski, David W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carmichael, Robert T. [Cadeo Group, Washington D. C. (United States); Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fisher, Andrew R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-17

    This report documents a national impact analysis of large tank heat pump water heaters (HPWH) in electric thermal storage (ETS) programs and conveys the findings related to concerns raised by utilities regarding the ability of large-tank heat pump water heaters to provide electric thermal storage services.

  19. Hybrid Particle Swarm Optimization based Day-Ahead Self-Scheduling for Thermal Generator in Competitive Electricity Market

    DEFF Research Database (Denmark)

    Pindoriya, Naran M.; Singh, S.N.; Østergaard, Jacob

    2009-01-01

    in day-ahead energy market subject to operational constraints and 2) at the same time, to minimize the risk due to uncertainty in price forecast. Therefore, it is a conflicting bi-objective optimization problem which has both binary and continuous optimization variables considered as constrained mixed......This paper presents a hybrid particle swarm optimization algorithm (HPSO) to solve the day-ahead self-scheduling for thermal power producer in competitive electricity market. The objective functions considered to model the self-scheduling problem are 1) to maximize the profit from selling energy...... integer nonlinear programming. To demonstrate the effectiveness of the proposed method for self-scheduling in a day-ahead energy market, the locational margin price (LMP) forecast uncertainty in PJM electricity market is considered. An adaptive wavelet neural network (AWNN) is used to forecast the day...

  20. Least cost analysis of Belarus electricity generation system with focus on nuclear option

    International Nuclear Information System (INIS)

    Mikhalevich, A.; Yakushau, A.

    2004-01-01

    A basic feature of the Belarus electricity system is that about 50% of the installed power capacity is used to produce heat for the central heating supply system. The Republic has one of the most developed districts heating system in Europe. The installation started in 1930, and developed very fast after 1945. Co-generation of electricity and thermal energy in central power plants has played a fundamental role in the local economy. Presently, Belarus electricity generation system includes: Total installed capacities of condensing turbines 3665 MW; Total installed capacities of co-generation turbines 3889 MW. It is expected that in 2020 in accordance with electricity demand forecast peak load demand will be equaled approximately 9500 MW. Taking into account that operation time of 60 % existent co-generation turbine and 70 % of condensing turbine can be extended up to 2020 during the period 2005 - 2020 it is necessity to install about 1500 MW of new co-generation units and about 2000 MW of condensing turbines. To select the least cost scenario for electricity generation system expansion improved computer code WASP-IV for Windows had been used. As far code WASP-IV do not allow finding out optimal solution for electricity generation system with high share of co-generation directly the methodology of application of this program for this case had been developed. Methodology is based on utilization of code WASP-IV for simulation condensing turbines and module BALANCE for modeling co-generation part of the system. The scenarios for the electricity system expansion plan included only conventional technologies. Presently, the works connected with the preparedness for NPP construction in the Republic including site survey for NPP are being carried out. The first stage of siting process according to the IAEA classification has been completed. It was based on a set of criteria answered to A Safety Guide of the IAEA Site Survey for Nuclear Power Plants and requirements to be

  1. Electric power in Canada 1993

    International Nuclear Information System (INIS)

    1994-01-01

    The electric power industry in Canada in 1993 is reviewed. Items discussed include: the international context of Canadian electricity; regulatory structures; electricity and the environment; electricity consumption; electricity generation; generating capacity and reserve; electricity trade; transmission; electric utility investment and financing; costing and pricing; electricity outlook; demand-side management; and non-utility generation. Appended information is presented on installed capacity and electrical energy consumption in Canada, installed generating capacity, conventional thermal capacity by principal fuel type, provincial electricity imports and exports, Canadian electricity exports by exporter and importer, generation capacity by type, installed generating capacity expansion in Canada by station, federal environmental standards and guidelines, and prices paid by major electric utilities for non-utility generation. 23 figs., 95 tabs

  2. Electric power in Canada 1992

    International Nuclear Information System (INIS)

    1993-01-01

    The electric power industry in Canada in 1991 is reviewed. Items discussed include: the international context of Canadian electricity; regulatory structures; electricity and the environment; electricity consumption; electricity generation; generating capacity and reserve; electricity trade; transmission; electric utility investment and financing; costing and pricing; electricity outlook; demand-side management; and non-utility generation. Appended information is presented on installed capacity and electrical energy consumption in Canada, installed generating capacity, conventional thermal capacity by principal fuel type, provincial electricity imports and exports, Canadian electricity exports by exporter and importer, generation capacity by type, installed generating capacity expansion in Canada by station, federal environmental standards and guidelines, and prices paid by major electric utilities for non-utility generation. 26 figs., 90 tabs

  3. Review on Automotive Power Generation System on Plug-in Hybrid Electric Vehicles & Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Leong Yap Wee

    2016-01-01

    Full Text Available Regenerative braking is a function to recharge power bank on the Plug-in electric vehicles (PHEV and electric vehicles (EV. The weakness of this system is, it can only perform its function when the vehicle is slowing down or by stepping the brake foot pedal. In other words, the electricity recharging system is inconsistent, non-continuous and geography dependent. To overcome the weakness of the regenerative braking system, it is suggested that to apply another generator which is going to be parallel with the regenerative braking system so that continuous charging can be achieved. Since the ironless electricity generator has a less counter electromotive force (CEMF comparing to an ironcored electricity generator and no cogging torque. Applying the ironless electricity generator parallel to the regenerative braking system is seen one of the options which creates sustainable charging system compared to cored electricity generator.

  4. Thermal and stress analyses in thermoelectric generator with tapered and rectangular pin configurations

    International Nuclear Information System (INIS)

    Yilbas, Bekir Sami; Akhtar, S.S.; Sahin, A.Z.

    2016-01-01

    Thermal stress developed in thermoelectric generators is critical for long service applications. High temperature gradients, due to a large temperature difference across the junctions, causes excessive stress levels developed in the device pins and electrodes at the interfaces. In the present study, a thermoelectric generator with horizontal pin configuration is considered and thermal stress analysis in the device is presented. Ceramic wafer is considered to resemble the high temperature plate and copper electrodes are introduced at the pin junctions to reduce the electrical resistance between the pins and the high and low temperature junction plates during the operation. Finite element code is used to simulate temperature and stress fields in the thermoelectric generator. In the simulations, convection and radiation losses from the thermoelectric pins are considered and bismuth telluride pin material with and without tapering is incorporated. It is found that von Mises stress attains high values at the interface between the hot and cold junctions and the copper electrodes. Thermal stress developed in tapered pin configuration attains lower values than that of rectangular pin cross-section. - Highlights: • Different cold junction temperatures improves thermoelectric generator performance. • von Mises stress remains high across copper electrodes and hot junction ceramics. • von Mises stress reduces along pin length towards cold junction. • Pin tapering lowers stress levels in thermoelectric generator.

  5. Tuning of the Seebeck Coefficient and the Electrical and Thermal Conductivity of Hybrid Materials Based on Polypyrrole and Bismuth Nanowires.

    Science.gov (United States)

    Hnida, Katarzyna E; Pilarczyk, Kacper; Knutelski, Marcin; Marzec, Mateusz; Gajewska, Marta; Kosonowski, Artur; Chlebda, Damian; Lis, Bartłomiej; Przybylski, Marek

    2018-04-06

    The growing demand for clean energy catalyzes the development of new devices capable of generating electricity from renewable energy resources. One of the possible approaches focuses on the use of thermoelectric materials (TE), which may utilize waste heat, water, and solar thermal energy to generate electrical power. An improvement of the performance of such devices may be achieved through the development of composites made of an organic matrix filled with nanostructured thermoelectric materials working in a synergetic way. The first step towards such designs requires a better understanding of the fundamental interactions between available materials. In this paper, this matter is investigated and the questions regarding the change of electrical and thermal properties of nanocomposites based on low-conductive polypyrrole enriched with bismuth nanowires of well-defined geometry and morphology is answered. It is clearly demonstrated that the electrical conductivity and the Seebeck coefficient may be tuned either simultaneously or separately within particular Bi NWs content ranges, and that both parameters may be increased at the same time. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A thermal study of an encapsulated electrical transformer

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, A. [Unidad Geotermia, Temixco (Mexico). Instituto de Investigaciones Electricas; Espinosa-Paredes, G. [Universidad Autonoma Metropolitana, Vicentina (Mexico). Dpto. de Ingenieria de Procesos e Hidraulica; Hernandez, I. [Centro de Sistemas de Manufactura, Nuevo Leon (Mexico). Instituto Tecnologico y de Estudios Superiores de Monterrey

    2002-11-01

    A thermal study of a 45 KVA-prototype encapsulated transformer is described. Casting resin systems were used as insulating systems for encapsulated electric transformers. Normal transformer operation is at full load and, thus the conductor and insulating system becomes hot owing to current circulation through the winding. To determine the various temperature distributions throughout the transformer, the thermal properties of the insulating system and boundary conditions must be known, so that hot spots are located via numerical modelling and maximum permissible temperatures are not attained. Results presented herein include thermal conductivity, thermal diffusivity, and specific heat capacity. Thermal conductivity was obtained experimentally by means of the line-source technique at various temperatures, between room temperature and 155{sup o}C which is the thermal limit of class F insulators. The thermal diffusivity was obtained by parameter estimation by fitting an approximate analytical model to the temperature-time data of the thermal conductivity experiment. Specific heat capacity was obtained from the definition of thermal diffusivity and the insulating-system density. In order to improve the electrical performance of the transformer criteria, a numerical simulation of the different dielectric structures was made using computer program. The boundary conditions for the thermal simulation stage were also determined experimentally from temperature test runs. Finally, in order to obtain data for thermal design, a numerical simulation of the high tension winding was carried out. The thermal simulation stage was performed at different current densities in the conductor with and without electrostatic shields to determine the temperature field and maximum attainable temperatures. Maximum transformer temperature were found to be 15-20{sup o}C below its thermal limit and a correlation of maximum temperature as function of circulating current was developed for design

  7. Electricity generation using electromagnetic radiation

    Science.gov (United States)

    Halas, Nancy J.; Nordlander, Peter; Neumann, Oara

    2017-08-22

    In general, in one aspect, the invention relates to a system to create vapor for generating electric power. The system includes a vessel comprising a fluid and a complex and a turbine. The vessel of the system is configured to concentrate EM radiation received from an EM radiation source. The vessel of the system is further configured to apply the EM radiation to the complex, where the complex absorbs the EM radiation to generate heat. The vessel of the system is also configured to transform, using the heat generated by the complex, the fluid to vapor. The vessel of the system is further configured to sending the vapor to a turbine. The turbine of the system is configured to receive, from the vessel, the vapor used to generate the electric power.

  8. Renewable energy distributed power system with photovoltaic/ thermal and bio gas power generators

    International Nuclear Information System (INIS)

    Haider, M.U.; Rehman, S.U.

    2011-01-01

    The energy shortage and environmental pollution is becoming an important problem in these days. Hence it is very much important to use renewable power technologies to get rid of these problems. The important renewable energy sources are Bio-Energy, Wind Energy, Hydrogen Energy, Tide Energy, Terrestrial Heat Energy, Solar Energy, Thermal Energy and so on. Pakistan is rich in all these aspects particularly in Solar and Thermal Energies. In major areas of Pakistan like in South Punjab, Sind and Baluchistan the weather condition are very friendly for these types of Renewable Energies. In these areas Solar Energy can be utilized by solar panels in conjunction with thermal panels. The Photovoltaic cells are used to convert Solar Energy directly to Electrical Energy and thermal panels can be uses to convert solar energy into heat energy and this heat energy will be used to drive some turbine to get Electrical Energy. The Solar Energy can be absorbed more efficiently by any given area of Solar Panel if these two technologies can be combined in such a way that they can work together. The first part of this paper shows that how these technologies can be combined. Furthermore it is known to all that photovoltaic/thermal panels depend entirely on weather conditions. So in order to maintain constant power a biogas generator is used in conjunction with these. (author)

  9. Energy demand of electricity generation

    International Nuclear Information System (INIS)

    Drahny, M.

    1992-01-01

    The complex energy balance method was applied to selected electricity generation subsystems. The hydroelectric, brown coal based, and nuclear based subsystems are defined. The complex energy balance basically consists in identifying the mainstream and side-stream energy inputs and outputs for both the individual components and the entire electricity generation subsystem considered. Relationships for the complete energy balance calculation for the i-th component of the subsystem are given, and its side-stream energy inputs and outputs are defined. (J.B.). 4 figs., 4 refs

  10. A global fouling factor methodology for analyzing steam generator thermal performance degradation

    International Nuclear Information System (INIS)

    Kreider, M.A.; White, G.A.; Varrin, R.D. Jr.

    1998-06-01

    Over the past few years, steam generator (SG) thermal performance degradation has led to decreased plant efficiency and power output at numerous PWR nuclear power plants with recirculating-type SGs. The authors have developed and implemented methodologies for quantitatively evaluating the various sources of SG performance degradation, both internal and external to the SG pressure boundary. These methodologies include computation of the global fouling factor history, evaluation of secondary deposit thermal resistance using deposit characterization data, and consideration of pressure loss causes unrelated to the tube bundle, such as hot-leg temperature streaming and SG moisture separator fouling. In order to evaluate the utility of the global fouling factor methodology, the authors performed case studies for a number of PWR SG designs. Key results from two of these studies are presented here. In tandem with the fouling-factor analyses, a study evaluated for each plant the potential causes of pressure loss. The combined results of the global fouling factor calculations and the pressure-loss evaluations demonstrated two key points: (1) that the available thermal margin against fouling, which can vary substantially from plant to plant, has an important bearing on whether a given plant exhibits losses in electrical generating capacity, and (2) that a wide variety of causes can result in SG thermal performance degradation

  11. Thermal and Electrical Conductivity Measurements of CDA 510 Phosphor Bronze

    Science.gov (United States)

    Tuttle, James E.; Canavan, Edgar; DiPirro, Michael

    2009-01-01

    Many cryogenic systems use electrical cables containing phosphor bronze wire. While phosphor bronze's electrical and thermal conductivity values have been published, there is significant variation among different phosphor bronze formulations. The James Webb Space Telescope (JWST) will use several phosphor bronze wire harnesses containing a specific formulation (CDA 510, annealed temper). The heat conducted into the JWST instrument stage is dominated by these harnesses, and approximately half of the harness conductance is due to the phosphor bronze wires. Since the JWST radiators are expected to just keep the instruments at their operating temperature with limited cooling margin, it is important to know the thermal conductivity of the actual alloy being used. We describe an experiment which measured the electrical and thermal conductivity of this material between 4 and 295 Kelvin.

  12. Differential and directional effects of perfusion on electrical and thermal conductivities in liver.

    Science.gov (United States)

    Podhajsky, Ronald J; Yi, Ming; Mahajan, Roop L

    2009-01-01

    Two different measurement probes--an electrical probe and a thermal conductivity probe--were designed, fabricated, calibrated, and used in experimental studies on a pig liver model that was designed to control perfusion rates. These probes were fabricated by photolithography and mounted in 1.5-mm diameter catheters. We measured the local impedance and thermal conductivity, respectively, of the artificially perfused liver at different flow rates and, by rotating the probes, in different directions. The results show that both the local electrical conductivity and the thermal conductivity varied location to location, that thermal conductivity increased with decreased distance to large blood vessels, and that significant directional differences exist in both electrical and thermal conductivities. Measurements at different perfusion rates demonstrated that both the local electrical and local thermal conductivities increased linearly with the square root of perfusion rate. These correlations may be of great value to many energy-based biomedical applications.

  13. The influence of value of intensity of constant electric field on structure, thermal physic and conductivity nanocomposites epoxy resin-oxide metal

    International Nuclear Information System (INIS)

    Vilensky, V.O.; Demchenko, V.I.

    2009-01-01

    Influence of constant electric field on structure, specific thermal capacity, thermomechanical properties and electrical conduction nanocomposites on a basis epoxy resin and fillers Fe 2 O 3 , Al 2 O 3 is investigated. The received results show, that application of constant electric field gives the chance to influence level of perfection of crystal structure filler (Fe 2 O 3 ) in structure to a composite, thus the size of crystals decreases from 18.0 nm (for initial samples of composites) to 7.7 nm (for the composites generated under the influence of CEF). Nanocomposites generated in CEF characterization the higher values of a electrical conduction

  14. Steam generator thermal-hydraulics

    International Nuclear Information System (INIS)

    Inch, W.W.; Scott, D.A.; Carver, M.B.

    1980-01-01

    This paper discusses a code for detailed numerical modelling of steam generator thermal-hydraulics, and describes related experimental programs designed to promote in-depth understanding of three-dimensional two-phase flow. (auth)

  15. Generation of net electric power with a tokamak reactor under foreseeable physical and engineering conditions

    International Nuclear Information System (INIS)

    Hiwatari, R.; Asaoka, Y.; Okano, K.; Yoshida, T.; Tomabechi, K.

    2004-01-01

    This study reveals for the first time the plasma performance required for a tokamak reactor to generate net electric power under foreseeable engineering conditions. It was found that the reference plasma performance of the ITER inductive operation mode with β N = 1.8, HH = 1.0, andf nGW 0.85 had sufficient potential to achieve the electric break-even condition (net electric power P e net = 0MW) under the following engineering conditions: machine major radius 6.5m ≤ R p ≤ 8.5m, the maximum magnetic field on TF coils B tmax = 16 T, thermal efficiency η e 30%, and NBI system efficiency η NBI = 50%. The key parameters used in demonstrating net electric power generation in tokamak reactors are β N and fη GW . ≥ 3.0 is required for P e net ∼ 600MW with fusion power P f ∼ 3000MW. On the other hand, fη GW ≥ 1.0 is inevitable to demonstrate net electric power generation, if high temperatures, such as average temperatures of T ave > 16 keV, cannot be selected for the reactor design. To apply these results to the design of a tokamak reactor for demonstrating net electric power generation, the plasma performance diagrams on the Q vs P f (energy multiplication factor vs fusion power) space for several major radii (i.e. 6.5, 7.5, and 8.5 m) were depicted. From these figures, we see that a design with a major radius R p ∼ 7.5m seems preferable for demonstrating net electric power generation when one aims at early realization of fusion energy. (author)

  16. Green power perspectives on sustainable electricity generation

    CERN Document Server

    Neiva de Figueiredo, Joao

    2014-01-01

    Green Power: Perspectives on Sustainable Electricity Generation; João Neiva de Figueiredo and Mauro GuillénAn Overview of Electricity Generation Sources; Akhil Jariwala and Saumil JariwalaGermany's Energy Revolution; José Carlos Thomaz, Jr. and Sean MichalsonChina's Energy Profile and the Importance of Coal; Julia Zheng and Xiaoting ZhengChina's Search for Cleaner Electricity Generation Alternatives; Julia Zheng and Xiaoting ZhengRenewable Energy in Spain: A Quest for Energy Security; José Normando Bezerra, Jr.Renewable Energy in French Polynesia: From Unpredictable to Energy Independence? Dia

  17. Developments in fossil fuel electricity generation

    International Nuclear Information System (INIS)

    Williams, A.; Argiri, M.

    1993-01-01

    A major part of the world's electricity is generated by the combustion of fossil fuels, and there is a significant environmental impact due to the production of fossil fuels and their combustion. Coal is responsible for 63% of the electricity generated from fossil fuels; natural gas accounts for about 20% and fuel oils for 17%. Because of developments in supply and improvements in generating efficiencies there is apparently a considerable shift towards a greater use of natural gas, and by the year 2000 it could provide 25% of the world electricity output. At the same time the amount of fuel oil burned will have decreased. The means to minimize the environmental impact of the use of fossil fuels, particularly coal, in electricity production are considered, together with the methods of emission control. Cleaner coal technologies, which include fluidized bed combustion and an integrated gasification combined cycle (IGCC), can reduce the emissions of NO x , SO 2 and CO 2 . (author)

  18. Problems associated with accelerated thermal aging of electrical equipment

    International Nuclear Information System (INIS)

    Isgro, J.R.

    1984-01-01

    This paper discusses the potential problems that may be experienced when accounting for aging mechanisms in organic polymers when utilizing accelerated thermal aging techniques for electrical equipment qualification. Included are discussions of actual experiences and problems encountered in the qualification of electrical and electronic equipment for a complete nuclear power plant. The wide variety of approaches to thermal accelerated aging by various manufacturers of diverse equipment types provides depth to the discussion. A description of how to account for aging mechanisms is also presented

  19. Solar thermal electric power information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-02-01

    The results of a series of telephone interviews with groups of users of information on solar thermal electric power are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from five solar thermal electric power groups of respondents are analyzed: DOE-Funded Researchers, Non-DOE-Funded Researchers, Representatives of Utilities, Electric Power Engineers, and Educators. The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  20. Electrically and Thermally Conducting Nanocomposites for Electronic Applications

    Directory of Open Access Journals (Sweden)

    Daryl Santos

    2010-02-01

    Full Text Available Nanocomposites made up of polymer matrices and carbon nanotubes are a class of advanced materials with great application potential in electronics packaging. Nanocomposites with carbon nanotubes as fillers have been designed with the aim of exploiting the high thermal, electrical and mechanical properties characteristic of carbon nanotubes. Heat dissipation in electronic devices requires interface materials with high thermal conductivity. Here, current developments and challenges in the application of nanotubes as fillers in polymer matrices are explored. The blending together of nanotubes and polymers result in what are known as nanocomposites. Among the most pressing current issues related to nanocomposite fabrication are (i dispersion of carbon nanotubes in the polymer host, (ii carbon nanotube-polymer interaction and the nature of the interface, and (iii alignment of carbon nanotubes in a polymer matrix. These issues are believed to be directly related to the electrical and thermal performance of nanocomposites. The recent progress in the fabrication of nanocomposites with carbon nanotubes as fillers and their potential application in electronics packaging as thermal interface materials is also reported.

  1. Thermoelectric power generator for variable thermal power source

    Science.gov (United States)

    Bell, Lon E; Crane, Douglas Todd

    2015-04-14

    Traditional power generation systems using thermoelectric power generators are designed to operate most efficiently for a single operating condition. The present invention provides a power generation system in which the characteristics of the thermoelectrics, the flow of the thermal power, and the operational characteristics of the power generator are monitored and controlled such that higher operation efficiencies and/or higher output powers can be maintained with variably thermal power input. Such a system is particularly beneficial in variable thermal power source systems, such as recovering power from the waste heat generated in the exhaust of combustion engines.

  2. A hybrid solar photovoltaic-wind turbine-Rankine cycle for electricity generation in Turkish Republic of Northern Cyprus

    Directory of Open Access Journals (Sweden)

    Samuel Asumadu-Sarkodie

    2016-12-01

    Full Text Available This paper presents an energy demand model by designing a hybrid solar-wind-thermal power generation system of the Turkish Republic of Northern Cyprus, a promising substitute for the expensive battery banks. The study models the future energy demand of Turkish Republic of Northern Cyprus based on the IPCC emissions scenario A1B and A2 by designing a new hybrid solar-wind-thermal power system that satisfies the current and future requirements of firm capacity during peak periods. The study suggests an improvement in a hybrid solar-wind-thermal power system performance by predicting reliable outputs that can integrate renewable energy technologies to conventional power generation. The energy consumption prediction model emphasizes the energy requirement that has a growing demand from 300 to 400 GWh in scenario A1B and 150–450 GWh in scenario A2 from 2010 to 2050. The proposed design can meet 400 GWh of electricity demand in TRNC based on IPCC scenario A1B and 450 GWh of electricity demand in TRNC based on IPCC scenario A2. The percentage contribution of solar, wind and thermal energy for 2010, 2020, 2030, 2040 and 2050 are presented along with CO2 emissions and water consumption for each of the years.

  3. Production function application attempt in electricity generation forecasting

    International Nuclear Information System (INIS)

    Kamrat, W.; Augusiak, A.

    1996-01-01

    A modified Cobb-Douglas production function is applied to evaluate level of electricity generation for medium and long term prognosis (up to 2010) in an easy and simple way. The test calculations have been done for hard coal fired power plants, based on generation data supplied in Main Statistical Office of Poland publications.The model of electricity generation is defined using data on capital of a typical productivity power plant and its employment for time series 1980-90. The test calculation results based on the parameters of Rosenbroock's optimization procedure of electricity generation model are presented. The method described is distinguished for its high accuracy as compared to classical methods despite the relatively short time series. It is suitable for studies in electricity generation policy . 1 tab

  4. ANALYSIS OF THE SPECIAL FEATURES OF THE THERMAL PROCESS IN AN INDUCTION GENERATOR AT HIGH SATURATION OF THE MAGNETIC SYSTEM

    Directory of Open Access Journals (Sweden)

    V. Chenchevoi

    2017-06-01

    Full Text Available Purpose. Development of the method for the assessment of the thermal operation modes of an autonomous electrical power system with an induction motor, aiming at improvement of the reliability of electricity supply and the quality of electric energy. Methodology. Induction generator mathematical modeling taking into account the magnetic system saturation was used in the research. A heat model taking into account the excess of the temperature of the induction generator units in the mode of high saturation was developed. The obtained results were compared with the experimental data. Results. The paper contains the solution to the problem of improvement of the mathematical model sand methods for steel losses determination in there search of the operation modes of an autonomous uncontrolled induction generator taking into consideration the properties of the magnetic system in the mode of high saturation. The expression for determination of steel losses in the mode of high saturation is obtained. It enables the assessment of the induction generator thermal condition. Originality. The analytical dependence for the calculation of the steel losses in the mode of magnetic system saturation has been obtained for the first time. Practical value. The obtained expression for the calculation of the steel losses can be used for determination of the admissible time of generator operation at overload. It will allow avoiding broken winding insulation and complete use of the generator overload capacity. As a result, it will reduce possible irregularities of electricity supply due to the generator preliminary cutoff.

  5. Inductive thermal plasma generation applied for the materials coating

    International Nuclear Information System (INIS)

    Pacheco, J.; Pena, R.; Cota, G.; Segovia, A.; Cruz, A.

    1996-01-01

    The coatings by thermal plasma are carried out introducing particles into a plasma system where they are accelerated and melted (total or partially) before striking the substrate to which they adhere and are suddenly cooled down. The nature of consolidation and solidification of the particles allows to have control upon the microstructure of the deposit. This technique is able to deposit any kind of material that is suitable to be merged (metal, alloy, ceramic, glass) upon any type of substrate (metal, graphite, ceramic, wood) with an adjustable thickness ranging from a few microns up to several millimeters. The applications are particularly focused to the coating of materials in order to improve their properties of resistance to corrosion, thermal and mechanical efforts as well as to preserve the properties of the so formed compound. In this work the electromagnetic induction phenomenon in an ionized medium by means of electric conductivity, is described. Emphasis is made on the devices and control systems employed in order to generate the thermal plasma and in carrying out the coatings of surfaces by the projection of particles based on plasma

  6. Nuclear Power for Electricity Generation in Ghana: Issues and Challenges

    International Nuclear Information System (INIS)

    Nyarko, B.J.B.; Akaho, E.H.K.; Ennison, I.

    2011-01-01

    Ghana's electricity demand has been estimated to be growing at a high rate of about 7% per annum over the last ten years. This is due to the relatively high population growth, economic aspiration of the country and the extension of electricity to rural areas. Electricity supply, on the contrary, has been unable to meet the demand due to high dependency on rain-fed hydropower plants, which started operating in 1965 and currently account for about 68% of the total installed capacity. Within the last 28 years, climatic changes and draughts have caused the nation to experience three major power crises. These climate changes resulted in low inflows and thus reduced power generation from hydropower systems. To complement the hydropower systems, the Government in 1997 installed thermal plants based on light crude oil. However, due to the high crude oil prices on the international market in recent times have made the operation of these plants very expensive. Ghana's crude oil find can boost its energy supply when the oil exploration begins somewhere in 2010. For rural cooking, domestic biomass is employed. Ghana has no domestic coal resources. The Government of Ghana is concerned with: limited further growth potential of domestic hydro; high cost of imported oil and gas and environmental issues associated with use of imported coal. Small Solar and wind generation exist in some sectors, but potential large-scale development is not envisioned for the near future. With these in mind, the President of Ghana set up a Committee involving Stakeholder Institutions to formulate the Nuclear Power Policy and develop the basic elements of Nuclear Infrastructure and to assess the viability of introducing the nuclear power option in Ghana's energy mix. Cabinet took a decision to include the nuclear power for electricity generation after the Committee submitted his report to the President in 2008. (author)

  7. Generation of Electric Energy and Desalinating Water from Solar Energy and the Oceans Hydropower

    Science.gov (United States)

    Elfikky, Niazi

    Brief.All warnings and fears about the environment in our Earth planet due to the serious effects of the industrial revolution were certainly predicted early. But the eager contest and the powerful desire for more profits beside the human interest for welfare and development closed all minds about the expected severe destuctive impacts on our earth planet. Also, we have to remember that the majority of the African, Asian and Latin American countries are still in the first stage of their development and if they will be left to generate all their demand of energy by the conventional machine e.g (Fossil Fuel, Biofuel and Nuclear Fuel), then our Earth planet will confront an endless and ceasless severe destructive impacts due to the encroach of the released hot Carbon Doxide and hot vapours of Acids which will never forgive any fruitful aspect in our Earth Planet from destruction. 1. Importance of the New Project. Building the Extra cheap, clean Power plants with safe and smooth Operation in addition to the long life time in service for generating enough and plentiful electric energy the sustainable renwable resources will invigorate the foresaking of all Nuclear, Fossil and Biofuel power plants to avoide the nuclear hazards and stop releasing the hot carbon doxide, hot acids for the recovery of our ill environment. Also, the main sustainable, renewable, and cheap resources for generating the bulky capacity of the electric energy in our project are the Sun and the Oceans in addition to all Seas Surrounding all Continents in our Earth planet. Therefore, our recourses are so much enormous plentiful, clean, and renewable. 2. .Generation of Electricity from Solar Energy by Photovoltiac Cells (PVCs) or Concentrated Solar Power (CSP). Characteristics of Photovoltiac Cells (PVCs). It is working only by Sun's Light (Light photons) and its efficiency will decrease as the Solar Thermal Radiation will increase, i.e. as the temerature of the Solar Voltiac will increase, its output

  8. Simulation-based Investigation of Electric Power Generation by Using Gamma Radiation from Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Haneol; Yim, Mansung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    This study investigates the feasibility of using gamma radiation energy from spent nuclear fuels to produce electricity as emergency power source. The proposed electric power system includes electricity generation and storage. Electricity generation was based on conversion of gamma energy to light energy using a scintillator and then to electric energy using a solar cell. Generated electricity was to be stored in a battery as a power source. The efficiency of energy conversion and the extent of the resulting electric power source capability were examined by computer model-based simulation. Main factors which affect to total electric power generated include thermal power of nuclear power plant, average burn-up period for fuel rod, battery charging time, and scintillator thickness. The estimated total power generation and its possible application is discussed. Although the output power increases as scintillator becomes thicker, thick scintillator can be problem because of its high price. There are two ways to solve this problem. The first one is to use thin scintillator to whole fuel assembly area. The second one is to use thick scintillator to limited region. But the current per fuel assembly for the first case for 4000MWth, 72 month burnup is about several to tens of microampere scale, which is too small to charge. Because of this the system is supposed to have thick scintillator system with limited region. Based on the results, the generated electricity is expected to be insufficient to operate the safety injection pumps even at the maximum power output. This may be important for security purposes. Based on the current design, the solar cell efficiency is estimated to be around 1.5-4%. As the efficiency is a strong function of scintillation wavelength, improving the efficiency may be possible by broadening the wavelength through the use of multiple scintillators. Future work will also include validation of the results through experiments, and material reliability

  9. Simulation-based Investigation of Electric Power Generation by Using Gamma Radiation from Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Lee, Haneol; Yim, Mansung

    2014-01-01

    This study investigates the feasibility of using gamma radiation energy from spent nuclear fuels to produce electricity as emergency power source. The proposed electric power system includes electricity generation and storage. Electricity generation was based on conversion of gamma energy to light energy using a scintillator and then to electric energy using a solar cell. Generated electricity was to be stored in a battery as a power source. The efficiency of energy conversion and the extent of the resulting electric power source capability were examined by computer model-based simulation. Main factors which affect to total electric power generated include thermal power of nuclear power plant, average burn-up period for fuel rod, battery charging time, and scintillator thickness. The estimated total power generation and its possible application is discussed. Although the output power increases as scintillator becomes thicker, thick scintillator can be problem because of its high price. There are two ways to solve this problem. The first one is to use thin scintillator to whole fuel assembly area. The second one is to use thick scintillator to limited region. But the current per fuel assembly for the first case for 4000MWth, 72 month burnup is about several to tens of microampere scale, which is too small to charge. Because of this the system is supposed to have thick scintillator system with limited region. Based on the results, the generated electricity is expected to be insufficient to operate the safety injection pumps even at the maximum power output. This may be important for security purposes. Based on the current design, the solar cell efficiency is estimated to be around 1.5-4%. As the efficiency is a strong function of scintillation wavelength, improving the efficiency may be possible by broadening the wavelength through the use of multiple scintillators. Future work will also include validation of the results through experiments, and material reliability

  10. Doping dependence of electrical and thermal conductivity of nanoscale polyaniline thin films

    Energy Technology Data Exchange (ETDEWEB)

    Jin Jiezhu; Wang Qing [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 (United States); Haque, M A [Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, PA 16802 (United States)

    2010-05-26

    We performed simultaneous characterization of electrical and thermal conductivity of 55 nm thick polyaniline (PANI) thin films doped with different levels of camphor sulfonic acids (CSAs). The effect of the doping level is more pronounced on electrical conductivity than on thermal conductivity of PANIs, thereby greatly affecting their ratio that determines the thermoelectric efficiency. At the 60% (the molar ratio of CSA to phenyl-N repeat unit of PANI) doping level, PANI exhibited the maximum electrical and thermal conductivity due to the formation of mostly delocalized structures. Whereas polarons are the charge carriers responsible for the electrical conduction, phonons are believed to play a dominant role in the heat conduction in nanoscale doped PANI thin films.

  11. Thermal acclimation and thyroxine treatment modify the electric organ discharge frequency in an electric fish, Apteronotus leptorhynchus.

    Science.gov (United States)

    Dunlap, K D; Ragazzi, M A

    2015-11-01

    In ectotherms, the rate of many neural processes is determined externally, by the influence of the thermal environment on body temperature, and internally, by hormones secreted from the thyroid gland. Through thermal acclimation, animals can buffer the influence of the thermal environment by adjusting their physiology to stabilize certain processes in the face of environmental temperature change. The electric organ discharge (EOD) used by weak electric fish for electrocommunication and electrolocation is highly temperature sensitive. In some temperate species that naturally experience large seasonal fluctuations in environmental temperature, the thermal sensitivity (Q10) of the EOD shifts after long-term temperature change. We examined thermal acclimation of EOD frequency in a tropical electric fish, Apteronotus leptorhynchus that naturally experiences much less temperature change. We transferred fish between thermal environments (25.3 and 27.8 °C) and measured EOD frequency and its thermal sensitivity (Q10) over 11 d. After 6d, fish exhibited thermal acclimation to both warming and cooling, adjusting the thermal dependence of EOD frequency to partially compensate for the small change (2.5 °C) in water temperature. In addition, we evaluated the thyroid influence on EOD frequency by treating fish with thyroxine or the anti-thyroid compound propylthiouricil (PTU) to stimulate or inhibit thyroid activity, respectively. Thyroxine treatment significantly increased EOD frequency, but PTU had no effect. Neither thyroxine nor PTU treatment influenced the thermal sensitivity (Q10) of EOD frequency during acute temperature change. Thus, the EOD of Apteronotus shows significant thermal acclimation and responds to elevated thyroxine. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Electrical-Generation Scenarios for China

    Energy Technology Data Exchange (ETDEWEB)

    Kypreos, S.; Krakowski, R.A.

    2002-03-01

    The China Energy Technology Program (CETP) used both optimizing and simulation energy- economic-environmental (E3) models to assess tradeoffs in the electricity-generation sector for a range of fuel, transport, generation, and distribution options. The CETP is composed of a range of technical tasks or activities, including Energy Economics Modeling (EEM, optimizations), Electric Sector Simulation (ESS, simulations), Life Cycle Analyses (LCA, externalization) of energy systems, and Multi-Criteria Decision Analyses (MCDA, integration). The scope of CETP is limited to one province (Shandong), to one economic sector (electricity), and to one energy sector (electricity). This document describes the methods, approaches, limitations, sample results, and future/needed work for the EEM ( optimization-based modeling) task that supports the overall goal of CETP. An important tool used by the EEM task is based on a Linear Programming (LP) optimization model that considers 17 electricity-generation technologies utilizing 14 fuel forms (type, composition, source) in a 7-region transportation model of China's electricity demand and supply system over the period 2000-2030; Shandong is one of the seven regions modeled. The China Regional Electricity Trade Model (CRETM) is used to examine a set of energy-environment-economy E3-driven scenarios to quantify related policy implications. The development of electricity production mixes that are optimized under realistically E3 constraints is determined through regional demands for electricity that respond to exogenous assumptions on income (GDP) and electricity prices through respective time-dependent elasticities. Constraints are applied to fuel prices, transportation limits, resource availability, introduction (penetration) rates of specific technology, and (where applicable) to local, regional, and countrywide emission rates of CO{sub 2}, SO{sub 2} and NO{sub x}. Importantly, future inter- regional energy flows are optimized with

  13. Thermal performances of molten salt steam generator

    International Nuclear Information System (INIS)

    Yuan, Yibo; He, Canming; Lu, Jianfeng; Ding, Jing

    2016-01-01

    Highlights: • Thermal performances of molten salt steam generator were experimentally studied. • Overall heat transfer coefficient reached maximum with optimal molten salt flow rate. • Energy efficiency first rose and then decreased with salt flow rate and temperature. • Optimal molten salt flow rate and temperature existed for good thermal performance. • High inlet water temperature benefited steam generating rate and energy efficiency. - Abstract: Molten salt steam generator is the key technology for thermal energy conversion from high temperature molten salt to steam, and it is used in solar thermal power station and molten salt reactor. A shell and tube type molten salt steam generator was set up, and its thermal performance and heat transfer mechanism were studied. As a coupling heat transfer process, molten salt steam generation is mainly affected by molten salt convective heat transfer and boiling heat transfer, while its energy efficiency is also affected by the heat loss. As molten salt temperature increased, the energy efficiency first rose with the increase of heat flow absorbed by water/steam, and then slightly decreased for large heat loss as the absorbed heat flow still rising. At very high molten salt temperature, the absorbed heat flow decreased as boiling heat transfer coefficient dropping, and then the energy efficiency quickly dropped. As the inlet water temperature increased, the boiling region in the steam generator remarkably expanded, and then the steam generation rate and energy efficiency both rose with the overall heat transfer coefficient increasing. As the molten salt flow rate increased, the wall temperature rose and the boiling heat transfer coefficient first increased and then decreased according to the boiling curve, so the overall heat transfer coefficient first increased and then decreased, and then the steam generation rate and energy efficiency of steam generator both had maxima.

  14. Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

    Science.gov (United States)

    Bowman, Charles D.

    1992-01-01

    Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

  15. Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

    Science.gov (United States)

    Bowman, C.D.

    1992-11-03

    Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

  16. Solar-TEP - Development of materials for thermo-electric power generators; SOLAR-TEP - Materialentwicklung fuer solarthermoelektrische Stromerzeuger - Schlussbericht 2008

    Energy Technology Data Exchange (ETDEWEB)

    Robert, R.; Weidenkaff, A.

    2008-06-15

    This final report for the Swiss Federal Office of Energy (SFOE) reports on the development of materials for thermo-electric power generators. Cobaltate phases are discussed as being suitable materials for thermoelectric applications at high temperatures. These potential thermoelectric materials are characterised with respect to their crystal structure, microstructure, composition, and thermal stability. The Seebeck coefficient, thermal conductivity and electrical resistivity of polycrystalline cobaltates with perovskite-type and layered-cobaltite structure are evaluated for a wide temperature range. The large Seebeck coefficient exhibited by both perovskite-type and layered cobaltite phases is analysed using the Heikes formula. The work is illustrated with results obtained for various materials in graphical form.

  17. Thermal modeling of secondary lithium batteries for electric vehicle/hybrid electric vehicle applications

    Science.gov (United States)

    Al-Hallaj, Said; Selman, J. R.

    A major obstacle to the development of commercially successful electric vehicles (EV) or hybrid electric vehicles (HEV) is the lack of a suitably sized battery. Lithium ion batteries are viewed as the solution if only they could be "scaled-up safely", i.e. if thermal management problems could be overcome so the batteries could be designed and manufactured in much larger sizes than the commercially available near-2-Ah cells. Here, we review a novel thermal management system using phase-change material (PCM). A prototype of this PCM-based system is presently being manufactured. A PCM-based system has never been tested before with lithium-ion (Li-ion) batteries and battery packs, although its mode of operation is exceptionally well suited for the cell chemistry of the most common commercially available Li-ion batteries. The thermal management system described here is intended specifically for EV/HEV applications. It has a high potential for providing effective thermal management without introducing moving components. Thereby, the performance of EV/HEV batteries may be improved without complicating the system design and incurring major additional cost, as is the case with "active" cooling systems requiring air or liquid circulation.

  18. Thermal energy storage for electricity-driven space heating in a day-ahead electricity market

    DEFF Research Database (Denmark)

    Pensini, Alessandro

    2012-01-01

    Thermal Energy Storage (TES) in a space heating (SH) application was investigated. The study aimed to determine the economic benefits of introducing TES into an electricity-driven SH system under a day-ahead electricity market. The performance of the TES was assessed by comparing the cost...... of electricity in a system with a TES unit to the case where no storage is in use and the entire heat requirement is fulfilled by purchasing electricity according to the actual load. The study had two goals: 1. Determining how the size – in terms of electricity input (Pmax) and energy capacity (Emax...

  19. 18 CFR 801.12 - Electric power generation.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Electric power generation. 801.12 Section 801.12 Conservation of Power and Water Resources SUSQUEHANNA RIVER BASIN COMMISSION GENERAL POLICIES § 801.12 Electric power generation. (a) Significant uses are presently being made...

  20. Modeling of a Thermoelectric Generator for Thermal Energy Regeneration in Automobiles

    Science.gov (United States)

    Tatarinov, Dimitri; Koppers, M.; Bastian, G.; Schramm, D.

    2013-07-01

    In the field of passenger transportation a reduction of the consumption of fossil fuels has to be achieved by any measures. Advanced designs of internal combustion engine have the potential to reduce CO2 emissions, but still suffer from low efficiencies in the range from 33% to 44%. Recuperation of waste heat can be achieved with thermoelectric generators (TEGs) that convert heat directly into electric energy, thus offering a less complicated setup as compared with thermodynamic cycle processes. During a specific driving cycle of a car, the heat currents and temperature levels of the exhaust gas are dynamic quantities. To optimize a thermoelectric recuperation system fully, various parameters have to be tested, for example, the electric and thermal conductivities of the TEG and consequently the heat absorbed and rejected from the system, the generated electrical power, and the system efficiency. A Simulink model consisting of a package for dynamic calculation of energy management in a vehicle, coupled with a model of the thermoelectric generator system placed on the exhaust system, determines the drive-cycle-dependent efficiency of the heat recovery system, thus calculating the efficiency gain of the vehicle. The simulation also shows the temperature drop at the heat exchanger along the direction of the exhaust flow and hence the variation of the voltage drop of consecutively arranged TEG modules. The connection between the temperature distribution and the optimal electrical circuitry of the TEG modules constituting the entire thermoelectric recuperation system can then be examined. The simulation results are compared with data obtained from laboratory experiments. We discuss error bars and the accuracy of the simulation results for practical thermoelectric systems embedded in cars.

  1. Electrical energy in France in 2009

    International Nuclear Information System (INIS)

    2009-12-01

    The figures presented on this document account for the electricity flows recorded in Metropolitan France, including Corsica. Contents: national consumption; physical exchanges with foreign countries; electrical energy balance in France in 2009; net generation; noteworthy data for the year 2009 (daily maximum values of national consumption, thermal generation, hydro-electric generation, wind generation and balance of physical exchanges); electricity market: cross-borders contractual exchanges, balance responsible entities (Energy amount exchanged between balance responsible entities through the block exchange notifications), balancing mechanism (global amount of energy activated upwards and downwards), daily market coupling; power facilities: generating facilities in France (Nuclear, Fossil fuel thermal, Hydro-electric, Wind and Other renewable energy sources), transmission lines owned by RTE (circuit length in operation), transmission - transformers owned by RTE (installed capacity in operation); main transmission facilities commissioned during the year 2009 (substations connected to the RTE network and new or refurbished circuits)

  2. The energetics of electric organ discharge generation in gymnotiform weakly electric fish.

    Science.gov (United States)

    Salazar, Vielka L; Krahe, Rüdiger; Lewis, John E

    2013-07-01

    Gymnotiform weakly electric fish produce an electric signal to sense their environment and communicate with conspecifics. Although the generation of such relatively large electric signals over an entire lifetime is expected to be energetically costly, supporting evidence to date is equivocal. In this article, we first provide a theoretical analysis of the energy budget underlying signal production. Our analysis suggests that wave-type and pulse-type species invest a similar fraction of metabolic resources into electric signal generation, supporting previous evidence of a trade-off between signal amplitude and frequency. We then consider a comparative and evolutionary framework in which to interpret and guide future studies. We suggest that species differences in signal generation and plasticity, when considered in an energetics context, will not only help to evaluate the role of energetic constraints in the evolution of signal diversity but also lead to important general insights into the energetics of bioelectric signal generation.

  3. Power generation investment in electricity markets

    International Nuclear Information System (INIS)

    2003-01-01

    Most IEA countries are liberalizing their electricity markets, shifting the responsibility for financing new investment in power generation to private investors. No longer able to automatically pass on costs to consumers, and with future prices of electricity uncertain, investors face a much riskier environment for investment in electricity infrastructure. This report looks at how investors have responded to the need to internalize investment risk in power generation. While capital and total costs remain the parameters shaping investment choices, the value of technologies which can be installed quickly and operated flexibly is increasingly appreciated. Investors are also managing risk by greater use of contracting, by acquiring retail businesses, and through mergers with natural gas suppliers. While liberalization was supposed to limit government intervention in the electricity market, volatile electricity prices have put pressure on governments to intervene and limit such prices. This study looks at several cases of volatile prices in IEA countries' electricity markets, and finds that while market prices can be a sufficient incentive for new investment in peak capacity, government intervention into the market to limit prices may undermine such investment

  4. Mini-biomass electric generation

    Energy Technology Data Exchange (ETDEWEB)

    Elliot, G. [International Applied Engineering, Inc., Atlanta, GA (United States)

    1997-12-01

    Awareness of the living standards achieved by others has resulted in a Russian population which is yearning for a higher standard of living. Such a situation demands access to affordable electricity in remote areas. Remote energy requirements creates the need to transport power or fossil fuels over long distances. Application of local renewable energy resources could eliminate the need for and costs of long distance power supply. Vast forest resources spread over most of Russia make biomass an ideal renewable energy candidate for many off-grid villages. The primary objective for this preliminary evaluation is to examine the economic feasibility of replacing distillate and gasoline fuels with local waste biomass as the primary fuel for village energy in outlying regions of Russia. Approximately 20 million people live in regions where Russia`s Unified Electric System grid does not penetrate. Most of these people are connected to smaller independent power grids, but approximately 8 million Russians live in off-grid villages and small towns served by stand-alone generation systems using either diesel fuel or gasoline. The off-grid villages depend on expensive distillate fuels and gasoline for combustion in small boilers and engines. These fuels are used for both electricity generation and district heating. Typically, diesel generator systems with a capacity of up to 1 MW serve a collective farm, settlement and their rural enterprises (there are an estimated 10,000 such systems in Russia). Smaller gasoline-fueled generator systems with capacities in the range of 0.5 - 5 kW serve smaller farms or rural enterprises (there are about 60,000 such systems in Russia).

  5. The projected costs of electricity generation

    International Nuclear Information System (INIS)

    Cameron, R.; Keppler, J. H.

    2010-10-01

    This paper describes the outcomes from the joint report between the Nuclear Energy Agency and the International Energy Agency of the OECD on the projected costs of generating electricity. The study contains data on electricity generating costs for almost 200 power plants provided by 17 OECD member countries, 4 non-OECD countries and 4 industrial companies or industry organisations. The paper presents the projected costs of generating electricity calculated according to common methodological rules on the basis of the data provided by participating countries and organisations. Data were received for a wide variety of fuels and technologies, including coal, gas, nuclear, hydro, onshore and offshore wind, biomass, solar, wave and tidal. Cost estimates were also provided for combined heat and power plants, as well as for coal plants that include carbon capture. As in previous studies of the same series, all costs and benefits were discounted or capitalised to the date of commissioning in order to calculate the state of the electricity costs per MWh, based on plant operating lifetime data. In addition, the paper contains a discussion of a number of factors affecting the cost of capital, the outlook for carbon capture and storage and the working of electricity markets. (Author)

  6. Analysis of the energy portfolio for electricity generation

    International Nuclear Information System (INIS)

    Ramirez S, J. R.; Alonso V, G.; Esquivel E, J.

    2016-09-01

    The planning of electricity generation systems considers several factors that must be taken into account in order to design systems that are economical, reliable and sustainable. For this purpose, the Financial Portfolio Theory is applicable to the energy portfolio or the diversification of electricity generation technologies, such as is the combined cycle, wind, thermoelectric and nuclear. This paper presents an application of the Portfolio Theory to the national energy system, based on the total generation costs for each technology, which allows determining the average variance portfolio and the respective share of each of the electricity generation technologies considered, obtaining a portfolio of electricity generation with the maximum possible return for the risk taken in the investments. This paper describes the basic aspects of the Portfolio Theory and its methodology, in which matrices are implemented for the solution of the resulting Lagrange system. (Author)

  7. Electricity Self-Generation Costs for Industrial Companies in Cameroon

    Directory of Open Access Journals (Sweden)

    Diboma Benjamin Salomon

    2010-07-01

    Full Text Available Industrial production in developing countries (DC is frequently perturbed by electric energy supply difficulties. To overcome this problem, generators are used in self-generation of energy, but this leads to an increase of electricity-related expenses. This article assesses the impact of electricity self-generation on Cameroonian industrial companies. The model described in this article is based on data collected through a survey of a representative sample of industrial companies and from numerous previous thematic and statistical studies. The results of our analyses show that expenses related to electricity in industrial companies in Cameroon have increased five times due to electricity rationing and untimely power cuts. The article also suggests some solutions to improve the electricity self-generation capacity of industrial companies.

  8. Thermal and Electrical Characterization of Alumina Substrate for Microelectronic Applications

    International Nuclear Information System (INIS)

    Ahmad, S.; Ibrahim, A.; Alias, R.; Shapee, S. M.; Ambak, Z.; Zakaria, S. Z.; Yahya, M. R.; Mat, A. F. A.

    2010-01-01

    This paper reports the effect of sintering temperature on thermal and electrical properties of alumina material as substrate for microelectronic devices. Alumina materials in the form of green sheet with 1 mm thickness were sintered at 1100 deg. C, 1300 deg. C and 1500 deg. C for about 20 hours using heating and cooling rates of 2 deg. C/min. The densities were measured using densitometer and the microstructures of the samples were analyzed using SEM micrographs. Meanwhile thermal and electrical properties of the samples were measured using flash method and impedance analyzer respectively. It was found that thermal conductivity and thermal diffusivity of the substrate increases as sintering temperature increases. It was found also that the dielectric constant of alumina substrate increases as the sintering temperature increases.

  9. Thermal and Electrical Characterization of Alumina Substrate for Microelectronic Applications

    Science.gov (United States)

    Ahmad, S.; Ibrahim, A.; Alias, R.; Shapee, S. M.; Ambak, Z.; Zakaria, S. Z.; Yahya, M. R.; Mat, A. F. A.

    2010-03-01

    This paper reports the effect of sintering temperature on thermal and electrical properties of alumina material as substrate for microelectronic devices. Alumina materials in the form of green sheet with 1 mm thickness were sintered at 1100° C, 1300° C and 1500° C for about 20 hours using heating and cooling rates of 2° C/min. The densities were measured using densitometer and the microstructures of the samples were analyzed using SEM micrographs. Meanwhile thermal and electrical properties of the samples were measured using flash method and impedance analyzer respectively. It was found that thermal conductivity and thermal diffusivity of the substrate increases as sintering temperature increases. It was found also that the dielectric constant of alumina substrate increases as the sintering temperature increases.

  10. Direct thermal to electrical energy conversion using 9.5/65/35 PLZT ceramics in the ergodic relaxor phase.

    Science.gov (United States)

    Chin, Thomas K; Lee, Felix Y; McKinley, Ian M; Goljahi, Sam; Lynch, Christopher S; Pilon, Laurent

    2012-11-01

    This paper reports on direct thermal to electrical energy conversion by performing the Olsen cycle on 9.5/65/35 lead lanthanum zirconate titanate (PLZT). The Olsen cycle consists of two isothermal and two isoelectric field processes in the electric displacement versus electric field diagram. It was performed by alternatively dipping the material in hot and cold dielectric fluid baths under specified electric fields. The effects of applied electric field, sample thickness, electrode material, operating temperature, and cycle frequency on the energy and power densities were investigated. A maximum energy density of 637 ± 20 J/L/cycle was achieved at 0.054 Hz with a 250-μm-thick sample featuring Pt electrodes and coated with a silicone conformal coating. The operating temperatures varied between 3°C and 140°C and the electric field was cycled between 0.2 and 6.0 MV/m. A maximum power density of 55 ± 8 W/L was obtained at 0.125 Hz under the same operating temperatures and electric fields. The dielectric strength of the material, and therefore the energy and power densities generated, increased when the sample thickness decreased from 500 to 250 μm. Furthermore, the electrode material was found to have no significant effect on the energy and power densities for samples subject to the same operating temperatures and electric fields. However, samples with electrode material possessing thermal expansion coefficients similar to that of PLZT were capable of withstanding larger temperature swings. Finally, a fatigue test showed that the power generation gradually degraded when the sample was subject to repeated thermoelectrical loading.

  11. Electricity prices and generator behaviour in gross pool electricity markets

    International Nuclear Information System (INIS)

    O'Mahoney, Amy; Denny, Eleanor

    2013-01-01

    Electricity market liberalisation has become common practice internationally. The justification for this process has been to enhance competition in a market traditionally characterised by statutory monopolies in an attempt to reduce costs to end-users. This paper endeavours to see whether a pool market achieves this goal of increasing competition and reducing electricity prices. Here the electricity market is set up as a sealed bid second price auction. Theory predicts that such markets should result with firms bidding their marginal cost, thereby resulting in an efficient outcome and lower costs to consumers. The Irish electricity system with a gross pool market experiences among the highest electricity prices in Europe. Thus, we analyse the Irish pool system econometrically in order to test if the high electricity prices seen there are due to participants bidding outside of market rules or out of line with theory. Overall we do not find any evidence that the interaction between generator and the pool in the Irish electricity market is not efficient. Thus, the pool element of the market structure does not explain the high electricity prices experienced in Ireland. - Highlights: • We consider whether a gross pool achieves competitive behaviour. • We analyse the Irish pool system econometrically. • Results indicate the Irish pool system appears to work efficiently. • Generators appear to be bidding appropriately

  12. Experimental investigation on performance of lithium-ion battery thermal management system using flat plate loop heat pipe for electric vehicle application

    International Nuclear Information System (INIS)

    Putra, Nandy; Ariantara, Bambang; Pamungkas, Rangga Aji

    2016-01-01

    Highlights: • Flat plate loop heat pipe (FPLHP) is studied in the thermal management system for electric vehicle. • Distilled water, alcohol, and acetone on thermal performances of FPLHP were tested. • The FPLHP can start up at fairly low heat load. • Temperature overshoot phenomena were observed during the start-up period. - Abstract: The development of electric vehicle batteries has resulted in very high energy density lithium-ion batteries. However, this growth is accompanied by the risk of thermal runaway, which can cause serious accidents. Heat pipes are heat exchangers that are suitable to be applied in electric vehicle battery thermal management for their lightweight and compact size, and they do not require external power supply. This study examined experimentally a flat plate loop heat pipe (FPLHP) performance as a heat exchanger in the thermal management system of the lithium-ion battery for electric vehicle application. The heat generation of the battery was simulated using a cartridge heater. Stainless steel screen mesh was used as the capillary wick. Distilled water, alcohol, and acetone were used as working fluids with a filling ratio of 60%. It was found that acetone gave the best performance that produces a thermal resistance of 0.22 W/°C with 50 °C evaporator temperature at heat flux load of 1.61 W/cm"2.

  13. solar thermal power systems advanced solar thermal technology project, advanced subsystems development

    Science.gov (United States)

    1979-01-01

    The preliminary design for a prototype small (20 kWe) solar thermal electric generating unit was completed, consisting of several subsystems. The concentrator and the receiver collect solar energy and a thermal buffer storage with a transport system is used to provide a partially smoothed heat input to the Stirling engine. A fossil-fuel combustor is included in the receiver designs to permit operation with partial or no solar insolation (hybrid). The engine converts the heat input into mechanical action that powers a generator. To obtain electric power on a large scale, multiple solar modules will be required to operate in parallel. The small solar electric power plant used as a baseline design will provide electricity at remote sites and small communities.

  14. Electric power engineering in the Taiwan Chinese Republic

    International Nuclear Information System (INIS)

    Kozlov, V.B.

    1992-01-01

    The data charaterizing the status and prospects of development of electric power engineering in the Taiwan Chenese Republic are given. The Tainwan electric power consumptions are covered by operation of 56 large electric power plants (nuclear, thermal, hydroelectric ones). The marginal majority (58.1%) of the registered power is generated at thermal power plants. Electric power generation in 1991 amounted to 89639 million kWxh. At that 33878 million kWxh or about 37.9% were produced at NPPs

  15. Proposed Use of Zero Bias Diode Arrays as Thermal Electric Noise Rectifiers and Non-Thermal Energy Harvesters

    Science.gov (United States)

    Valone, Thomas F.

    2009-03-01

    The well known built-in voltage potential for some select semiconductor p-n junctions and various rectifying devices is proposed to be favorable for generating DC electricity at "zero bias" (with no DC bias voltage applied) in the presence of Johnson noise or 1/f noise which originates from the quantum vacuum (Koch et al., 1982). The 1982 Koch discovery that certain solid state devices exhibit measurable quantum noise has also recently been labeled a finding of dark energy in the lab (Beck and Mackey, 2004). Tunnel diodes are a class of rectifiers that are qualified and some have been credited with conducting only because of quantum fluctuations. Microwave diodes are also good choices since many are designed for zero bias operation. A completely passive, unamplified zero bias diode converter/detector for millimeter (GHz) waves was developed by HRL Labs in 2006 under a DARPA contract, utilizing a Sb-based "backward tunnel diode" (BTD). It is reported to be a "true zero-bias diode." It was developed for a "field radiometer" to "collect thermally radiated power" (in other words, 'night vision'). The diode array mounting allows a feed from horn antenna, which functions as a passive concentrating amplifier. An important clue is the "noise equivalent power" of 1.1 pW per root hertz and the "noise equivalent temperature difference" of 10° K, which indicate sensitivity to Johnson noise (Lynch, et al., 2006). There also have been other inventions such as "single electron transistors" that also have "the highest signal to noise ratio" near zero bias. Furthermore, "ultrasensitive" devices that convert radio frequencies have been invented that operate at outer space temperatures (3 degrees above zero point: 3° K). These devices are tiny nanotech devices which are suitable for assembly in parallel circuits (such as a 2-D array) to possibly produce zero point energy direct current electricity with significant power density (Brenning et al., 2006). Photovoltaic p-n junction

  16. Electric distribution systems and embedded generation capacity

    International Nuclear Information System (INIS)

    Calderaro, V.; Galdi, V.; Piccolo, A.; Siano, P.

    2006-01-01

    The main policy issues of European States are sustainable energy supply promotion and liberalization of energy markets, which introduced market competition in electricity production and created support mechanisms to encourage renewable electricity production and consumption. As a result of liberalization, any generator, including small-scale and renewable energy based units, can sell electricity on the free market. In order to meet future sustainability targets, connection of a higher number of Distributed Generation (DG) units to the electrical power system is expected, requiring changes in the design and operation of distribution electricity systems, as well as changes in electricity network regulation. In order to assist distribution system operators in planning and managing DG connections and in maximizing DG penetration and renewable sources exploitation, this paper proposed a reconfiguration methodology based on a Genetic Algorithm (GA), that was tested on a 70-bus system with DG units. The simulation results confirmed that the methodology represents a suitable tool for distribution system operators when dealing with DG capacity expansion and power loss issues, providing information regarding the potential penetration network-wide and allowing maximum exploitation of renewable generation. 35 refs., 4 tabs., 6 figs

  17. Numerical simulations on the temperature gradient and thermal stress of a thermoelectric power generator

    International Nuclear Information System (INIS)

    Wu, Yongjia; Ming, Tingzhen; Li, Xiaohua; Pan, Tao; Peng, Keyuan; Luo, Xiaobing

    2014-01-01

    Highlights: • An appropriate ceramic plate thickness is effective in alleviating the thermal stress. • A smaller distance between thermo-pins can help prolong lifecycle of the TE module. • Either a thicker or a thinner copper conducting strip effectively reduces thermal stress. • A suitable tin soldering thickness will alleviate thermal stress intensity and increase thermal efficiency. - Abstract: Thermoelectric generator is a device taking advantage of the temperature difference in thermoelectric material to generate electric power, where the higher the temperature difference of the hot-cold ends, the higher the efficiency will be. However, higher temperature or higher heat flux upon the hot end will cause strong thermal stress which will negatively influence the lifecycle of the thermoelectric module. This phenomenon is very common in industrial applications but seldom has research work been reported. In this paper, numerical analysis on the thermodynamics and thermal stress performance of the thermoelectric module has been performed, considering the variation on the thickness of materials; the influence of high heat flux on thermal efficiency, power output, and thermal stress has been examined. It is found that under high heat flux imposing upon the hot end, the thermal stress is so strong that it has a decisive effect on the life expectation of the device. To improve the module’s working condition, different geometrical configurations are tested and the optimum sizes are achieved. Besides, the side effects on the efficiency, power output, and open circuit voltage output of the thermoelectric module are taken into consideration

  18. Characterization of Contact and Bulk Thermal Resistance of Laminations for Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Cousineau, J. Emily [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bennion, Kevin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DeVoto, Doug [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mihalic, Mark [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Narumanchi, Sreekant [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-06-30

    The ability to remove heat from an electric machine depends on the passive stack thermal resistances within the machine and the convective cooling performance of the selected cooling technology. This report focuses on the passive thermal design, specifically properties of the stator and rotor lamination stacks. Orthotropic thermal conductivity, specific heat, and density are reported. Four materials commonly used in electric machines were tested, including M19 (29 and 26 gauge), HF10, and Arnon 7 materials.

  19. A Combined Optical, Thermal and Electrical Performance Study of a V-Trough PV System—Experimental and Analytical Investigations

    Directory of Open Access Journals (Sweden)

    Haitham M. Bahaidarah

    2015-04-01

    Full Text Available The objective of this study was to achieve higher efficiency of a PV system while reducing of the cost of energy generation. Concentration photovoltaics was employed in the present case as it uses low cost reflectors to enhance the efficiency of the PV system and simultaneously reduces the cost of electricity generation. For this purpose a V-trough integrated with the PV system was employed for low concentration photovoltaic (LCPV. Since the electrical output of the concentrating PV system is significantly affected by the temperature of the PV cells, the motivation of the research also included studying the ability to actively cool PV cells to achieve the maximum benefit. The optical, thermal and electrical performance of the V-trough PV system was theoretically modeled and validated with experimental results. Optical modeling of V-trough was carried out to estimate the amount of enhanced absorbed radiation. Due to increase in the absorbed radiation the module temperature was also increased which was predicted by thermal model. Active cooling techniques were studied and the effect of cooling was analyzed on the performance of V-trough PV system. With absorbed radiation and module temperature as input parameters, electrical modeling was carried out and the maximum power was estimated. For the V-trough PV system, experiments were performed for validating the numerical models and very good agreement was found between the two.

  20. An improved theoretical electrochemical-thermal modelling of lithium-ion battery packs in electric vehicles

    Science.gov (United States)

    Amiribavandpour, Parisa; Shen, Weixiang; Mu, Daobin; Kapoor, Ajay

    2015-06-01

    A theoretical electrochemical thermal model combined with a thermal resistive network is proposed to investigate thermal behaviours of a battery pack. The combined model is used to study heat generation and heat dissipation as well as their influences on the temperatures of the battery pack with and without a fan under constant current discharge and variable current discharge based on electric vehicle (EV) driving cycles. The comparison results indicate that the proposed model improves the accuracy in the temperature predication of the battery pack by 2.6 times. Furthermore, a large battery pack with four of the investigated battery packs in series is simulated in the presence of different ambient temperatures. The simulation results show that the temperature of the large battery pack at the end of EV driving cycles can reach to 50 °C or 60 °C in high ambient temperatures. Therefore, thermal management system in EVs is required to maintain the battery pack within the safe temperature range.

  1. Coal-fired electricity generation in Ontario

    International Nuclear Information System (INIS)

    2001-03-01

    This report examines coal-fired electricity generation in Ontario and recommends actions to be taken by the provincial government to protect the environment. The recommendations are also designed to assist in making decisions about the environmental safeguards needed for a competitive electricity industry. The report examines air emissions from coal-fired generating plants in the larger context of air pollution in the province; summarizes background information on key air pollutants; provides an individual profile of all coal-fired power stations in the province; and benchmarks Ontario's emissions performance by comparing it with 19 nearby U.S. jurisdictions. Current and proposed environmental controls for fossil fuel power generation in the province are elaborated. Options for maximizing environmental performance and the framework for strengthening environmental protection are reviewed. The report also contains a series of findings and recommendations which are deemed necessary before the moratorium imposed on the sale of coal-fired electricity plants imposed in May 2000, can be lifted. tabs., figs

  2. Nuclear Power for Future Electricity Generation in Ghana: Issues and Challenges

    International Nuclear Information System (INIS)

    Nyarko, B.J.B.; Akaho, E.H.K.; Ennison, I.

    2011-01-01

    Ghana's electricity demand has been estimated to be growing at a high rate of about 7% per annum over the last ten years. This is due to the relatively high population growth, economic aspiration of the country and the extension of electricity to rural areas. Electricity supply, on the contrary, has been unable to meet the demand due to high dependency on rain-fed hydropower plants, which started operating in 1965 and currently account for about 68% of the total installed capacity. Within the last 28 years, climatic changes and draughts have caused the nation to experience three major power crises. These climate changes resulted in low inflows and thus reduced power generation from hydropower systems. To complement the hydropower systems, the Government in 1997 installed thermal plants based on light crude oil. However, due to the high crude oil prices on the international market in recent times have made the operation of these plants very expensive. Ghana's crude oil find can boost its energy supply when the oil exploration begins somewhere in 2010. For rural cooking, domestic biomass is employed. Ghana has no domestic coal resources. The Government of Ghana is concerned with: limited further growth potential of domestic hydro; high cost of imported oil and gas and environmental issues associated with use of imported coal. Small Solar and wind generation exist in some sectors, but potential large-scale development is not envisioned for the near future. With these in mind, the President of Ghana set up a Committee involving Stakeholder Institutions to formulate the Nuclear Power Policy and develop the basic elements of Nuclear Infrastructure and to assess the viability of introducing the nuclear power option in Ghana's energy mix. Cabinet took a decision to include the nuclear power for electricity generation after the Committee submitted his report to the President in 2008. (author)

  3. Electricity generation modeling and photovoltaic forecasts in China

    Science.gov (United States)

    Li, Shengnan

    With the economic development of China, the demand for electricity generation is rapidly increasing. To explain electricity generation, we use gross GDP, the ratio of urban population to rural population, the average per capita income of urban residents, the electricity price for industry in Beijing, and the policy shift that took place in China. Ordinary least squares (OLS) is used to develop a model for the 1979--2009 period. During the process of designing the model, econometric methods are used to test and develop the model. The final model is used to forecast total electricity generation and assess the possible role of photovoltaic generation. Due to the high demand for resources and serious environmental problems, China is pushing to develop the photovoltaic industry. The system price of PV is falling; therefore, photovoltaics may be competitive in the future.

  4. Electricity trade: Generating benefits for British Columbians

    International Nuclear Information System (INIS)

    1994-01-01

    Electricity has been traded in British Columbia since the turn of the century. In 1988, the provincial government established the British Columbia Power Exchange Corporation (Powerex) to conduct electricity trade activities in order to make the most efficient use of the electrial system and generate benefits for British Columbians. The trade is made possible by an interconnected system linking producers and consumers in western Canada and the USA. Provincial participants in the trade include British Columbia Hydro, independent power producers, and cogenerators. Benefits of the electricity trade include generation of revenue from sale of surplus power, being able to buy electricity when the mainly hydroelectric provincial system is in a drought condition or when major shutdowns occur, and enabling postponement of development of new power projects. Powerex conducts its trade under provincial and federal permits and licenses. Different types of trade contracts are negotiated depending on the amount and availability of electricity and the kind of trade being conducted. Exchanges and coordination agreements allow transfer and return between utilities with no net export occurring, allowing balancing of loads between different reigons. Surplus electricity is bought or sold on a short- or long-term basis and on firm or non-firm terms. Electricity exports are not subsidized and are only allowed if the electricity is surplus to provincial needs and can be sold at a profit. A new provincial policy allows private industry to export long-term firm electricity; this involves construction of new private-sector generating facilities solely for the purpose of export. 1 fig

  5. On-line energy and battery thermal management for hybrid electric heavy-duty truck

    NARCIS (Netherlands)

    Pham, H.T.; Kessels, J.T.B.A.; Bosch, van den P.P.J.; Huisman, R.G.M.; Nevels, R.M.P.A.

    2013-01-01

    This paper discusses an integrated approach for energy and thermal management to minimize the fuel consumption of a hybrid electric heavy-duty truck. Conventional Energy Management Systems (EMS) operate separately from the Battery Thermal Management System (BTMS) in Hybrid Electric Vehicles (HEVs).

  6. Entropy generation of viscous dissipative flow in thermal non-equilibrium porous media with thermal asymmetries

    International Nuclear Information System (INIS)

    Chee, Yi Shen; Ting, Tiew Wei; Hung, Yew Mun

    2015-01-01

    The effect of thermal asymmetrical boundaries on entropy generation of viscous dissipative flow of forced convection in thermal non-equilibrium porous media is analytically studied. The two-dimensional temperature, Nusselt number and entropy generation contours are analysed comprehensively to provide insights into the underlying physical significance of the effect on entropy generation. By incorporating the effects of viscous dissipation and thermal non-equilibrium, the first-law and second-law characteristics of porous-medium flow are investigated via various pertinent parameters, i.e. heat flux ratio, effective thermal conductivity ratio, Darcy number, Biot number and averaged fluid velocity. For the case of symmetrical wall heat flux, an optimum condition with a high Nusselt number and a low entropy generation is identified at a Darcy number of 10 −4 , providing an ideal operating condition from the second-law aspect. This type of heat and fluid transport in porous media covers a wide range of engineering applications, involving porous insulation, packed-bed catalytic process in nuclear reactors, filtration transpiration cooling, and modelling of transport phenomena of microchannel heat sinks. - Highlights: • Effects of thermal asymmetries on convection in porous-medium are studied. • Exergetic effectiveness of porous media with thermal asymmetries is investigated. • 2-D temperature, Nusselt number and entropy generation contours are analyzed. • Significance of viscous dissipation in entropy generation is scrutinized. • Significance of thermal non-equilibrium in entropy generation is studied

  7. Perspectives of the electric power industry amid the transforming global power generation markets

    Science.gov (United States)

    Makarov, A. A.; Mitrova, T. A.; Veselov, F. V.; Galkina, A. A.; Kulagin, V. A.

    2017-10-01

    A scenario-based prognosis of the evolution of global power generation markets until 2040, which was developed using the Scaner model-and-information complex, was given. The perspective development of fuel markets, vital for the power generation industry, was considered, and an attempt to predict the demand, production, and prices of oil, gas, coal, and noncarbon resources across various regions of the world was made. The anticipated decline in the growth of the global demand for fossil fuels and their sufficiency with relatively low extraction expenses will maintain the fuel prices (the data hereinafter are given as per 2014 prices) lower than their peak values in 2012. The outrunning growth of demand for electric power is shown in comparison with other power resources by regions and large countries in the world. The conditions of interfuel competition in the electric power industry considering the changes in anticipated fuel prices and cost indicators for various power generation technologies were studied. For this purpose, the ratios of discounted costs of electric power production by new gas and coal TPPs and wind and solar power plants were estimated. It was proven that accounting the system effects (operation modes, necessary duplicating and reserving the power of electric power plants using renewable energy sources) notably reduces the competitiveness of the renewable power industry and is not always compensated by the expected lowering of its capital intensity and growth of fuel for TPPs. However, even with a moderate (in relation to other prognoses) growth of the role of power plants using renewable energy sources, they will triple electric power production. In this context, thermal power plants will preserve their leadership covering up to 60% of the global electric power production, approximately half using gas.

  8. Air pollution implications of Nigeria's present strategy on improved electricity generation

    Energy Technology Data Exchange (ETDEWEB)

    Sonibare, J.A. [Environmental Engineering Research Laboratory, Department of Chemical Engineering, Obafemi Awolowo University, Ile-Ife (Nigeria)

    2010-10-15

    One of the strategies being developed in Nigeria to increase the presently installed electricity generation of 6159 MW to the required 30,000 MW is the adoption of electric thermal plants. An emission factor approach is used in this paper to study the emission of uncontrolled air pollutants from all the existing and proposed thermal plants in the country. Calculations are performed to study the distribution of carbon monoxide (CO), oxides of nitrogen (NO{sub X}), particulate matters (PM), sulphur dioxide (SO{sub 2}), and volatile organic compounds (VOCs). The estimated emissions ranges are 978-24,607, 1635-41,148, 37-924, 19-472, and 11-286 ton/annum for CO, NO{sub X}, PM, SO{sub 2}, and VOCs, respectively. The present locations of these plants across the country are characterized by skewed emission distribution both per capita and across the land. Given the potential environmental and health impacts of these emissions, several measures are suggested to reduce future impacts and assist the country in achieving sustainable development. (author)

  9. Projected costs of electricity generation

    International Nuclear Information System (INIS)

    Cameron, R.

    2010-01-01

    This paper describes the outcomes of a study on the projected costs of generating electricity. It presents the latest data available on electricity generating costs for a wide variety of fuels and technologies, including coal, gas, nuclear, hydro, onshore and offshore wind, biomass, solar, wave and tidal. The study reaches 2 key conclusions. First, at a 5% real interest rate, nuclear energy is the most competitive solution for base-load electricity generation followed by coal-fired plants without carbon capture and natural gas-fired combined plants. It should be noted that coal with carbon capture has not reached a commercial phase. Second, at a 10% interest rate, nuclear remains the most competitive in Asia and North America but in Europe, coal without carbon capture equipment, followed by coal with carbon capture equipment, and gas-fired combined cycle turbines are overall more competitive than nuclear energy. The results highlight the paramount importance of interest rates (this dependence is a direct consequence of the nuclear energy's high capital costs) and of the carbon price. For instance if we assume a 10% interest rate and a cost of 50 dollar per tonne of CO 2 , nuclear energy would become competitive against both coal and gas. (A.C.)

  10. Incorporating environmental constraints to electricity generation in the city of Buenos Aires

    International Nuclear Information System (INIS)

    Dawidowski, Laura E.; Gomez, Dario R.; Bajano, Hector; Anbinder, Gustavo D.; Rey, Francisco C.

    1999-01-01

    A prototype for an integrated system that includes air quality constraints to the procedure that is presently in use to determine the daily economic dispatch of power plants in Argentina is proposed. The recent incorporation of new machines to the installed capacity of the three power plants located in the densely populated metropolitan area of Buenos Aires, the thermal-based future expansion of the power sector and the relatively high nitrogen oxides concentrations that can be associated to electricity generation in the city of Buenos Aires, served to motivate this work. The prototype attempts to generate a dispatch that is compatible with the environment taking into account the present economic dispatch, weather forecast and dispersion models to evaluate ambient air concentrations of nitrogen oxides (NO x ) caused by the combined operation of the thermal power plants. Although the prototype deals exclusively with NO x , since these are the pollutants of primary concern considering the fuel consumption pattern of argentinean power plants, its structure is general enough to take into account other pollutants such as sulfur dioxide and particulate matter. (author)

  11. Cooling of superconducting electric generators by liquid helium

    International Nuclear Information System (INIS)

    Nakayama, W.; Ogata, H.

    1987-01-01

    Superconducting generators have a great potential in future electric supply systems in increasing the efficiency of generators and in enhancing the stability of power network systems. Recognition of possible advantages over gas-cooled and water-cooled generators has led research institutes and manufacturers in several countries to wage substantial research and development efforts. The authors show the electric power capacities of the test generators already built, under construction, or in the planning stage. Since earlier attempts, steady improvements in the design of generators have been made, and experience of generator operation has been accumulated

  12. A large electrically excited synchronous generator

    DEFF Research Database (Denmark)

    2014-01-01

    This invention relates to a large electrically excited synchronous generator (100), comprising a stator (101), and a rotor or rotor coreback (102) comprising an excitation coil (103) generating a magnetic field during use, wherein the rotor or rotor coreback (102) further comprises a plurality...... adjacent neighbouring poles. In this way, a large electrically excited synchronous generator (EESG) is provided that readily enables a relatively large number of poles, compared to a traditional EESG, since the excitation coil in this design provides MMF for all the poles, whereas in a traditional EESG...... each pole needs its own excitation coil, which limits the number of poles as each coil will take up too much space between the poles....

  13. Developing an optimal electricity generation mix for the UK 2050 future

    International Nuclear Information System (INIS)

    Sithole, H.; Cockerill, T.T.; Hughes, K.J.; Ingham, D.B.; Ma, L.; Porter, R.T.J.; Pourkashanian, M.

    2016-01-01

    The UK electricity sector is undergoing a transition driven by domestic and regional climate change and environmental policies. Aging electricity generating infrastructure is set to affect capacity margins after 2015. These developments, coupled with the increased proportion of inflexible and variable generation technologies will impact on the security of electricity supply. Investment in low-carbon technologies is central to the UK meeting its energy policy objectives. The complexity of these challenges over the future development of the UK electricity generation sector has motivated this study which aims to develop a policy-informed optimal electricity generation scenario to assess the sector's transition to 2050. The study analyses the level of deployment of electricity generating technologies in line with the 80% by 2050 emission target. This is achieved by using an excel-based “Energy Optimisation Calculator” which captures the interaction of various inputs to produce a least-cost generation mix. The key results focus on the least-cost electricity generation portfolio, emission intensity, and total investment required to assemble a sustainable electricity generation mix. A carbon neutral electricity sector is feasible if low-carbon technologies are deployed on a large scale. This requires a robust policy framework that supports the development and deployment of mature and emerging technologies. - Highlights: • Electricity generation decarbonised in 2030 and nearly carbon neutral in 2050. • Nuclear, CCS and offshore wind are central in decarbonising electricity generation. • Uncertainty over future fuel and investment cost has no impact on decarbonisation. • Unabated fossil fuel generation is limited unless with Carbon Capture and Storage. • Decarbonising the electricity generation could cost about £213.4 billion by 2030.

  14. Alternative solutions for electricity generation

    International Nuclear Information System (INIS)

    Kuenstle, K.

    1976-01-01

    Ten illustrations - mainly comparitive ones - dealing with the possibilities of an economical energy conversion, in particular electricity generation, in the FRG are explained and commented upon. (UA) [de

  15. Wind electric power generation

    International Nuclear Information System (INIS)

    Koch, M. K.; Wind, L.; Canter, B.; Moeller, T.

    2002-01-01

    The monthly statistics of wind electric power generation in Denmark are compiled from information given by the owners of the private wind turbines. For each wind turbine the name of the site and of the type of turbine is given, and the power generation data are given for the month in question together with the total production in 2000 and 2001. Also the data of operation start are given. On the map of Denmark the sites of the wind turbines are marked. (SM)

  16. Wind electric power generation

    International Nuclear Information System (INIS)

    Koch, M.K.; Wind, L.; Canter, B.; Moeller, T.

    2001-01-01

    The monthly statistics of wind electric power generation in Denmark are compiled from information given by the owners of the private wind turbines. For each wind turbine the name of the site and of the type of turbine is given, and the power generation data are given for the month in question together with the total production in 1999 and 2000. Also the data of operation start are given. On the map of Denmark the sites of the wind turbines are marked. (CLS)

  17. Generation Companies’ Operative Strategies in the Spot Electricity Market

    Directory of Open Access Journals (Sweden)

    Tovar-Hernández J.H.

    2012-07-01

    Full Text Available In traditional regulation the obligation to meet the consumer demand was assumed, this guaranteed to generation companies the full recovery of their costs. However, in order to achieve greater efficiency, reduce the price of electricity, meet the continuously growing electricity consumption, and equalize prices in different regions, a new structure of the electricity industry has been created, where electric energy is traded through a market. Generation company’s future cash flows depend on day to day market participation, in order to satisfy all of their financial and economic requirements. In this paper, future cash flows required to fulfill with economic and financial commitments by a generation company immerse in this new market structure are studied. For this purpose, future cash flows are considered to be dependent on a single asset: electricity. Several scenarios with different fuel prices are generated in order to estimate the generation company’s future cash flows. The response of the competing generation companies is taken into account at each scenario. The fuel price changes are modelled using a concurrent binary tree.

  18. Feasibility study of superconducting power cables for DC electric railway feeding systems in view of thermal condition at short circuit accident

    Science.gov (United States)

    Kumagai, Daisuke; Ohsaki, Hiroyuki; Tomita, Masaru

    2016-12-01

    A superconducting power cable has merits of a high power transmission capacity, transmission losses reduction, a compactness, etc., therefore, we have been studying the feasibility of applying superconducting power cables to DC electric railway feeding systems. However, a superconducting power cable is required to be cooled down and kept at a very low temperature, so it is important to reveal its thermal and cooling characteristics. In this study, electric circuit analysis models of the system and thermal analysis models of superconducting cables were constructed and the system behaviors were simulated. We analyzed the heat generation by a short circuit accident and transient temperature distribution of the cable to estimate the value of temperature rise and the time required from the accident. From these results, we discussed a feasibility of superconducting cables for DC electric railway feeding systems. The results showed that the short circuit accident had little impact on the thermal condition of a superconducting cable in the installed system.

  19. Electrical and Thermal Conductivity and Conduction Mechanism of Ge2Sb2Te5 Alloy

    Science.gov (United States)

    Lan, Rui; Endo, Rie; Kuwahara, Masashi; Kobayashi, Yoshinao; Susa, Masahiro

    2018-06-01

    Ge2Sb2Te5 alloy has drawn much attention due to its application in phase-change random-access memory and potential as a thermoelectric material. Electrical and thermal conductivity are important material properties in both applications. The aim of this work is to investigate the temperature dependence of the electrical and thermal conductivity of Ge2Sb2Te5 alloy and discuss the thermal conduction mechanism. The electrical resistivity and thermal conductivity of Ge2Sb2Te5 alloy were measured from room temperature to 823 K by four-terminal and hot-strip method, respectively. With increasing temperature, the electrical resistivity increased while the thermal conductivity first decreased up to about 600 K then increased. The electronic component of the thermal conductivity was calculated from the Wiedemann-Franz law using the resistivity results. At room temperature, Ge2Sb2Te5 alloy has large electronic thermal conductivity and low lattice thermal conductivity. Bipolar diffusion contributes more to the thermal conductivity with increasing temperature. The special crystallographic structure of Ge2Sb2Te5 alloy accounts for the thermal conduction mechanism.

  20. Electrical and Thermal Conductivity and Conduction Mechanism of Ge2Sb2Te5 Alloy

    Science.gov (United States)

    Lan, Rui; Endo, Rie; Kuwahara, Masashi; Kobayashi, Yoshinao; Susa, Masahiro

    2017-11-01

    Ge2Sb2Te5 alloy has drawn much attention due to its application in phase-change random-access memory and potential as a thermoelectric material. Electrical and thermal conductivity are important material properties in both applications. The aim of this work is to investigate the temperature dependence of the electrical and thermal conductivity of Ge2Sb2Te5 alloy and discuss the thermal conduction mechanism. The electrical resistivity and thermal conductivity of Ge2Sb2Te5 alloy were measured from room temperature to 823 K by four-terminal and hot-strip method, respectively. With increasing temperature, the electrical resistivity increased while the thermal conductivity first decreased up to about 600 K then increased. The electronic component of the thermal conductivity was calculated from the Wiedemann-Franz law using the resistivity results. At room temperature, Ge2Sb2Te5 alloy has large electronic thermal conductivity and low lattice thermal conductivity. Bipolar diffusion contributes more to the thermal conductivity with increasing temperature. The special crystallographic structure of Ge2Sb2Te5 alloy accounts for the thermal conduction mechanism.

  1. Sustainability evaluation of decentralized electricity generation

    International Nuclear Information System (INIS)

    Karger, Cornelia R.; Hennings, Wilfried

    2009-01-01

    Decentralized power generation is gaining significance in liberalized electricity markets. An increasing decentralization of power supply is expected to make a particular contribution to climate protection. This article investigates the advantages and disadvantages of decentralized electricity generation according to the overall concept of sustainable development. On the basis of a hierarchically structured set of sustainability criteria, four future scenarios for Germany are assessed, all of which describe different concepts of electricity supply in the context of the corresponding social and economic developments. The scenarios are developed in an explorative way according to the scenario method and the sustainability criteria are established by a discursive method with societal actors. The evaluation is carried out by scientific experts. By applying an expanded analytic hierarchy process (AHP), a multicriteria evaluation is conducted that identifies dissent among the experts. The results demonstrate that decentralized electricity generation can contribute to climate protection. The extent to which it simultaneously guarantees security of supply is still a matter of controversy. However, experts agree that technical and economic boundary conditions are of major importance in this field. In the final section, the article discusses the method employed here as well as implications for future decentralized energy supply. (author)

  2. Liberation of electric power and nuclear power generation

    International Nuclear Information System (INIS)

    Yajima, Masayuki

    2000-01-01

    In Japan, as the Rule on Electric Business was revised after an interval of 35 years in 1995, and a competitive bid on new electric source was adopted after 1996 fiscal year, investigation on further competition introduction to electric power market was begun by establishment of the Basic Group of the Electric Business Council in 1997. By a report proposed on January, 1999 by the Group, the Rule was revised again on March, 1999 to start a partial liberation or retail of the electric power from March, 2000. From a viewpoint of energy security and for solution of global environmental problem in Japan it has been decided to positively promote nuclear power in future. Therefore, it is necessary to investigate how the competition introduction affects to development of nuclear power generation and what is a market liberation model capable of harmonizing with the development on liberation of electric power market. Here was elucidated on effect of the introduction on previous and future nuclear power generation, after introducing new aspects of nuclear power problems and investigating characteristic points and investment risks specific to the nuclear power generation. And, by investigating some possibilities to development of nuclear power generation under liberation models of each market, an implication was shown on how to be future liberation on electric power market in Japan. (G.K.)

  3. Parametric studies and optimisation of pumped thermal electricity storage

    International Nuclear Information System (INIS)

    McTigue, Joshua D.; White, Alexander J.; Markides, Christos N.

    2015-01-01

    Highlights: • PTES is modelled by cycle analysis and a Schumann-style model of the thermal stores. • Optimised trade-off surfaces show a flat efficiency vs. energy density profile. • Overall roundtrip efficiencies of around 70% are not inconceivable. - Abstract: Several of the emerging technologies for electricity storage are based on some form of thermal energy storage (TES). Examples include liquid air energy storage, pumped heat energy storage and, at least in part, advanced adiabatic compressed air energy storage. Compared to other large-scale storage methods, TES benefits from relatively high energy densities, which should translate into a low cost per MW h of storage capacity and a small installation footprint. TES is also free from the geographic constraints that apply to hydro storage schemes. TES concepts for electricity storage rely on either a heat pump or refrigeration cycle during the charging phase to create a hot or a cold storage space (the thermal stores), or in some cases both. During discharge, the thermal stores are depleted by reversing the cycle such that it acts as a heat engine. The present paper is concerned with a form of TES that has both hot and cold packed-bed thermal stores, and for which the heat pump and heat engine are based on a reciprocating Joule cycle, with argon as the working fluid. A thermodynamic analysis is presented based on traditional cycle calculations coupled with a Schumann-style model of the packed beds. Particular attention is paid to the various loss-generating mechanisms and their effect on roundtrip efficiency and storage density. A parametric study is first presented that examines the sensitivity of results to assumed values of the various loss factors and demonstrates the rather complex influence of the numerous design variables. Results of an optimisation study are then given in the form of trade-off surfaces for roundtrip efficiency, energy density and power density. The optimised designs show a

  4. Model Thermoelectric Generator TEG Small Modular As Micro Electricity Plant At Indonesia Part 1 Design And Material

    Directory of Open Access Journals (Sweden)

    Kisman M. Mahmud

    2015-08-01

    Full Text Available Thermoelectrically Generator TEG can generate electricity from the temperature difference between hot and cold at the junction thermoelectric module with two different semiconductor materials there will be a flow of current through the junction so as to produce a voltage. This principle uses the Seebeck effect thermoelectric generator as a base. By using these principles this study was conducted to determine the potential of the electric energy of the two Peltier modules which would be an alternative source for micro electricity plant using heat from methylated. The focus of this research is to design a model TEG Thermoelectric Generator Small Modular to produce the kind of material that is optimum for a TEG on the simulation Computer Aided Design CAD with a variety of four different materials that Bi2Te3 Bismuth Telluride PbTe-BiTe CMO-32 -62S Cascade and CMO-32-62S Calcium Manganese Oxide to its cold side using the heat sink fan and simulating heat aluminum plate attached to the hot side of the TEG modules with heat source of methylated. Model simulation results on TEG Small Modular micro electrical plant material obtained CMO-32-62S Cascade thermal material that has a value greater than 3 other material.

  5. New electricity generating installations - Czech experience

    International Nuclear Information System (INIS)

    Biza, K.; Pazdera, F.; Zdarek, J.

    2004-01-01

    Economically and technically are analysed alternatives for new electricity generation installations (GEN 111+ NPPs, finalization of NPPs under construction, lifetime extension of existing NPPs, coal plants and gas plants). Described are experienced with NPP Temelin (lessons learned from its design, construction, start-up and resent operation and service experience) and new Czech Energy Policy, where the nuclear energy is an important source for electricity generation. Discussed is also impact of potential trading with CO 2 limits and strategy on minimization of dependence on energy from politically unstable regions. Underlined is important role of preparation of young generation for safe and reliable long term operation of NPPs. General recommendation is to orient on finalization of NPPs under construction, lifetime extension of existing NPPs and long term orientation on new generation of NPPs (GEN III+ and GEN IV). (author)

  6. Scenarios of Expansion to Electric Generation Capacity

    Directory of Open Access Journals (Sweden)

    José Somoza-Cabrera

    2017-06-01

    Full Text Available We show the building scenarios of expansion to electric generation capacity enough to supply the demand to 2050. We were using the LEAP facility (Long-range Energy Alternatives Planning System, to simulate dispatch of electricity at minimum cost. Finally, we show the cost-benefice analysis of the technologies availability, included externality and CO2 emission limited. However that we included the externals cost in this analysis, it results insufficient to closed gap between fossil and renewable technologies of electric generation. Nevertheless, in some opportunities the renewable options had very important participations in the minimal cost scenario of expansion.

  7. Electricity generating system. [Wind/diesel/flywheel system

    Energy Technology Data Exchange (ETDEWEB)

    Moody, R.L.

    1992-02-05

    An electricity generating system is described which includes a water tank with electric heating elements connected to the water cooling system of a diesel engine which is heated by excess output of the system. Power in excess of that required by a load which is generated by a wind turbine driven generator runs up a flywheel and further excess is absorbed in the tank. A fan associated with a radiator connected to the tank may be operated to dissipate further excess power. When the load requirements exceed the output of the generators linked to the wind turbine and the flywheel the engine operates a synchronous alternator. (author).

  8. Thermal energy harvesting for application at MEMS scale

    CERN Document Server

    Percy, Steven; McGarry, Scott; Post, Alex; Moore, Tim; Cavanagh, Kate

    2014-01-01

    This book discusses the history of thermal heat generators and focuses on the potential for these processes using micro-electrical mechanical systems (MEMS) technology for this application. The main focus is on the capture of waste thermal energy for example from industrial processes, transport systems or the human body to generate useable electrical power.  A wide range of technologies is discussed, including external combustion heat cycles at MEMS ( Brayton, Stirling and Rankine), Thermoacoustic, Shape Memory Alloys (SMAs), Multiferroics, Thermionics, Pyroelectric, Seebeck, Alkali Metal Thermal, Hydride Heat Engine, Johnson Thermo Electrochemical Converters, and the Johnson Electric Heat Pipe.

  9. Natural gas utilization in Santa Cruz thermal-electric power; A utilizacao de gas natural em Santa Cruz

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, Mauricio F. de.; Lundeqvist, Carl G; Gomes, Gerson; Almeida, A E

    1994-12-31

    Use of natural gas as an alternative energy source on the thermo electric power plant of Santa Cruz are presented. Economic studies on hydroelectric power plants to use thermal generators during low water supply periods, costs of natural gas as a alternative energy fuel, and the engineer services to the conversion of fuel oil system, are discussed. 5 figs., 6 tabs.

  10. Improvement and evaluation of thermal, electrical, sealing and mechanical contacts, and their interface materials

    Science.gov (United States)

    Luo, Xiangcheng

    Material contacts, including thermal, electrical, seating (fluid sealing and electromagnetic sealing) and mechanical (pressure) contacts, together with their interface materials, were, evaluated, and in some cases, improved beyond the state of the art. The evaluation involved the use of thermal, electrical and mechanical methods. For thermal contacts, this work evaluated and improved the heat transfer efficiency between two contacting components by developing various thermal interface pastes. Sodium silicate based thermal pastes (with boron nitride particles as the thermally conductive filler) as well as polyethylene glycol (PEG) based thermal pastes were developed and evaluated. The optimum volume fractions of BN in sodium silicate based pastes and PEG based pastes were 16% and 18% respectively. The contribution of Li+ ions to the thermal contact conductance in the PEG-based paste was confirmed. For electrical contacts, the relationship between the mechanical reliability and electrical reliability of solder/copper and silver-epoxy/copper joints was addressed. Mechanical pull-out testing was conducted on solder/copper and silver-epoxy/copper joints, while the contact electrical resistivity was measured. Cleansing of the copper surface was more effective for the reliability of silver-epoxy/copper joint than that of solder/copper joint. For sealing contacts, this work evaluated flexible graphite as an electromagnetic shielding gasket material. Flexible graphite was found to be at least comparable to conductive filled silicone (the state of the art) in terms of the shielding effectiveness. The conformability of flexible graphite with its mating metal surface under repeated compression was characterized by monitoring the contact electrical resistance, as the conformability is important to both electromagnetic scaling and fluid waling using flexible graphite. For mechanical contacts, this work focused on the correlation of the interface structure (such as elastic

  11. Comparative Study on Electric Generation Cost of HTR with Another Electric Plant Using LEGECOST Program

    International Nuclear Information System (INIS)

    Mochamad-Nasrullah; Soetrisnanto, Arnold Y.; Tosi-Prastiadi; Adiwardojo

    2000-01-01

    Monetary and economic crisis in Indonesia resulted in impact of electricity and demand and supply planning that it has to be reevaluated. One of the reasons is budget limitation of the government as well as private companies. Considering this reason, the economic calculation for all of aspect could be performed, especially the calculation of electric generation cost. This paper will discuss the economic aspect of several power plants using fossil and nuclear fuel including High Temperature Reactor (HTR). Using Levelized Generation Cost (LEGECOST) program developed by IAEA (International Atomic Energy Agency), the electric generation cost of each power plant could be calculated. And then, the sensitivity analysis has to be done using several economic parameters and scenarios, in order to be known the factors that influence the electric generation cost. It could be concluded, that the electric generation cost of HTR is cheapest comparing the other power plants including nuclear conventional. (author)

  12. Self generation, small generation, and embedded generation issues

    International Nuclear Information System (INIS)

    2001-01-01

    The New Brunswick Market Design Committee for electric power restructuring has been directed to examine issues regarding cogeneration and small-scale, on-site generation and how they will fit within the framework of the bilateral contract market. The Committee will also have to deal with issues of generation embedded in a distribution system. The Committee has defined cogeneration as the simultaneous production of electricity and useful thermal energy. Self-generation has been defined as small-scale power generation by an end-user, while embedded generation has been defined as a generation facility that is located within a distribution utility but is not directly connected to the transmission system. The Committee has postponed its decision on whether embedded generation will be eligible to participate under the bilateral contract market for electricity. This report discusses general issues such as the physical support of generation, market support of generation, transition issues and policy issues. It also discusses generation support issues such as operating reserves, transmission tariff issues, and distribution tariffs. Market support issues such as transmission access for generation sales were also considered, along with market access for generation sales, and net metering for behind the meter generation. 7 refs., 1 tab

  13. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-06-13

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil - by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines are presented.

  14. Renewable Electricity Futures Study. Volume 2: Renewable Electricity Generation and Storage Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Augustine, C.; Bain, R.; Chapman, J.; Denholm, P.; Drury, E.; Hall, D.G.; Lantz, E.; Margolis, R.; Thresher, R.; Sandor, D.; Bishop, N.A.; Brown, S.R.; Cada, G.F.; Felker, F.

    2012-06-01

    The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%-90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT).

  15. Measurements on a solar greenhouse combining cooling and electrical energy production

    NARCIS (Netherlands)

    B. van Tuijl; Piet Sonneveld; H. Janssen; J. van Campen; G. Bot; Gert-Jan Swinkels

    2010-01-01

    Performance results are given of a new type of greenhouse, which combines reflection of near infrared radiation (NIR) with electrical power generation using hybrid photovoltaic cell/thermal collector modules. Besides the generation of electrical and thermal energy, the reflection of the NIR will

  16. Big-Data-Based Thermal Runaway Prognosis of Battery Systems for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jichao Hong

    2017-07-01

    Full Text Available A thermal runaway prognosis scheme for battery systems in electric vehicles is proposed based on the big data platform and entropy method. It realizes the diagnosis and prognosis of thermal runaway simultaneously, which is caused by the temperature fault through monitoring battery temperature during vehicular operations. A vast quantity of real-time voltage monitoring data is derived from the National Service and Management Center for Electric Vehicles (NSMC-EV in Beijing. Furthermore, a thermal security management strategy for thermal runaway is presented under the Z-score approach. The abnormity coefficient is introduced to present real-time precautions of temperature abnormity. The results illustrated that the proposed method can accurately forecast both the time and location of the temperature fault within battery packs. The presented method is flexible in all disorder systems and possesses widespread application potential in not only electric vehicles, but also other areas with complex abnormal fluctuating environments.

  17. Effect of energy-regenerative braking on electric vehicle battery thermal management and control method based on simulation investigation

    International Nuclear Information System (INIS)

    Huang, Jingying; Qin, Datong; Peng, Zhiyuan

    2015-01-01

    Highlights: • A two-degree-of-freedom lumped thermal model is developed for battery. • The battery thermal model is integrated with vehicle driving model. • Real-time battery thermal responses is obtained. • Active control of current by regenerative braking ratio adjustment is proposed. • More energy is recovered with smaller battery temperature rise. - Abstract: Battery thermal management is important for the safety and reliability of electric vehicle. Based on the parameters obtained from battery hybrid pulse power characterization test, a two-degree-of-freedom lumped thermal model is established. The battery model is then integrated with vehicle driving model to simulate real-time battery thermal responses. An active control method is proposed to reduce heat generation due to regenerative braking. The proposed control method not only subjects to the braking safety regulation, but also adjusts the regenerative braking ratio through a fuzzy controller. By comparing with other regenerative braking scenarios, the effectiveness of the proposed strategy has been validated. According to the results, the proposed control strategy suppresses battery temperature rise by modifying the charge current due to regenerative braking. The overlarge components of current are filtered out whereas the small ones are magnified. Therefore, with smaller battery temperature rise, more energy is recovered. Compared to the traditional passive heat dissipating, the proposed active methodology is feasible and provides a novel solution for electric vehicle battery thermal management.

  18. Life cycle assessment of electricity generation in Mexico

    International Nuclear Information System (INIS)

    Santoyo-Castelazo, E.; Gujba, H.; Azapagic, A.

    2011-01-01

    This paper presents for the first time a Life Cycle Assessment (LCA) study of electricity generation in Mexico. The electricity mix in Mexico is dominated by fossil fuels, which contribute around 79% to the total primary energy; renewable energies contribute 16.5% (hydropower 13.5%, geothermal 3% and wind 0.02%) and the remaining 4.8% is from nuclear power. The LCA results show that 225 TWh of electricity generate about 129 million tonnes of CO 2 eq. per year, of which the majority (87%) is due to the combustion of fossil fuels. The renewables and nuclear contribute only 1.1% to the total CO 2 eq. Most of the other LCA impacts are also attributed to the fossil fuel options. The results have been compared with values reported for other countries with similar electricity mix, including Italy, Portugal and the UK, showing good agreement. -- Highlights: → This paper presents for the first time a Life Cycle Assessment (LCA) study of electricity generation in Mexico. → 129 million tonnes of CO 2 eq. per year are emitted from 225 TWh of electricity generated per year of which 87% is due to the combustion of fossil fuels. → Coal technologies generate 1094 g CO 2 eq./kWh, heavy fuel oil 964 g CO 2 eq./kWh, and gas 468 g CO 2 eq./kWh; by contrast, nuclear and hydro emit 12 g CO 2 eq./kWh. → Heavy fuel oil contributes most to the life cycle environmental impacts (59-97%). → The results show good agreement with values reported for other countries with similar electricity mix, including Italy, Portugal and the UK.

  19. PV Thermal systems: PV panels supplying renewable electricity and heat

    NARCIS (Netherlands)

    Helden, van W.G.J.; Zolingen, van R.J.C.; Zondag, H.A.

    2004-01-01

    With PV Thermal panels sunlight is converted into electricity and heat simultaneously. Per unit area the total efficiency of a PVT panel is higher than the sum of the efficiencies of separate PV panels and solar thermal collectors. During the last 20 years research into PVT techniques and concepts

  20. External electric field driving the ultra-low thermal conductivity of silicene.

    Science.gov (United States)

    Qin, Guangzhao; Qin, Zhenzhen; Yue, Sheng-Ying; Yan, Qing-Bo; Hu, Ming

    2017-06-01

    The manipulation of thermal transport is in increasing demand as heat transfer plays a critical role in a wide range of practical applications, such as efficient heat dissipation in nanoelectronics and heat conduction hindering in solid-state thermoelectrics. It is well established that the thermal transport in semiconductors and insulators (phonons) can be effectively modulated by structure engineering or materials processing. However, almost all the existing approaches involve altering the original atomic structure of materials, which would be hindered due to either irreversible structure change or limited tunability of thermal conductivity. Motivated by the inherent relationship between phonon behavior and interatomic electrostatic interaction, we comprehensively investigate the effect of external electric field, a widely used gating technique in modern electronics, on the lattice thermal conductivity (κ). Taking two-dimensional silicon (silicene) as a model, we demonstrate that by applying an electric field (E z = 0.5 V Å -1 ) the κ of silicene can be reduced to a record low value of 0.091 W m -1 K -1 , which is more than two orders of magnitude lower than that without an electric field (19.21 W m -1 K -1 ) and is even comparable to that of the best thermal insulation materials. Fundamental insights are gained from observing the electronic structures. With an electric field applied, due to the screened potential resulting from the redistributed charge density, the interactions between silicon atoms are renormalized, leading to phonon renormalization and the modulation of phonon anharmonicity through electron-phonon coupling. Our study paves the way for robustly tuning phonon transport in materials without altering the atomic structure, and would have significant impact on emerging applications, such as thermal management, nanoelectronics and thermoelectrics.

  1. Wind electric power generation

    International Nuclear Information System (INIS)

    Groening, B.; Koch, M.; Canter, B.; Moeller, T.

    1995-01-01

    The monthly statistics of wind electric power generation in Denmark are compiled from information given by the owners of private wind turbines. For each wind turbine the name of the site and of the type of turbine is given, and the power generation data are given for the month in question together with the total production in 1988 and 1989. Also the data of operation start are given. On the map of Denmark the sites of the wind turbines are marked. The statistics for December 1994 comprise 2328 wind turbines

  2. Detailed partial load investigation of a thermal energy storage concept for solar thermal power plants with direct steam generation

    Science.gov (United States)

    Seitz, M.; Hübner, S.; Johnson, M.

    2016-05-01

    Direct steam generation enables the implementation of a higher steam temperature for parabolic trough concentrated solar power plants. This leads to much better cycle efficiencies and lower electricity generating costs. For a flexible and more economic operation of such a power plant, it is necessary to develop thermal energy storage systems for the extension of the production time of the power plant. In the case of steam as the heat transfer fluid, it is important to use a storage material that uses latent heat for the storage process. This leads to a minimum of exergy losses during the storage process. In the case of a concentrating solar power plant, superheated steam is needed during the discharging process. This steam cannot be superheated by the latent heat storage system. Therefore, a sensible molten salt storage system is used for this task. In contrast to the state-of-the-art thermal energy storages within the concentrating solar power area of application, a storage system for a direct steam generation plant consists of a latent and a sensible storage part. Thus far, no partial load behaviors of sensible and latent heat storage systems have been analyzed in detail. In this work, an optimized fin structure was developed in order to minimize the costs of the latent heat storage. A complete system simulation of the power plant process, including the solar field, power block and sensible and latent heat energy storage calculates the interaction between the solar field, the power block and the thermal energy storage system.

  3. Study of the electrical and thermal performances of photovoltaic thermal collector-compound parabolic concentrated

    Science.gov (United States)

    Jaaz, Ahed Hameed; Sopian, Kamaruzzaman; Gaaz, Tayser Sumer

    2018-06-01

    The importance of utilizing the solar energy as a very suitable source among multi-source approaches to replace the conventional energy is on the rise in the last four decades. The invention of the photovoltaic module (PV) could be the corner stone in this process. However, the limited amount of energy obtained from PV was and still the main challenge of full utilization of the solar energy. In this paper, the use of the compound parabolic concentrator (CPC) along with the thermal photovoltaic module (PVT) where the cooling process of the CPC is conducted using a novel technique of water jet impingement has applied experimentally and physically tested. The test includes the effect of water jet impingement on the total power, electrical efficiency, thermal efficiency, and total efficiency on CPC-PVT system. The cooling process at the maximum irradiation by water jet impingement resulted in improving the electrical efficiency by 7%, total output power by 31% and the thermal efficiency by 81%. These results outperform the recent highest results recorded by the most recent work.

  4. Automatic Generation Control Study in Two Area Reheat Thermal Power System

    Science.gov (United States)

    Pritam, Anita; Sahu, Sibakanta; Rout, Sushil Dev; Ganthia, Sibani; Prasad Ganthia, Bibhu

    2017-08-01

    Due to industrial pollution our living environment destroyed. An electric grid system has may vital equipment like generator, motor, transformers and loads. There is always be an imbalance between sending end and receiving end system which cause system unstable. So this error and fault causing problem should be solved and corrected as soon as possible else it creates faults and system error and fall of efficiency of the whole power system. The main problem developed from this fault is deviation of frequency cause instability to the power system and may cause permanent damage to the system. Therefore this mechanism studied in this paper make the system stable and balance by regulating frequency at both sending and receiving end power system using automatic generation control using various controllers taking a two area reheat thermal power system into account.

  5. Horizontal steam generator PGV-1000 thermal-hydraulic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ubra, O. [Skoda Company, Prague (Switzerland); Doubek, M. [Czech Technical Univ., Prague (Switzerland)

    1995-12-31

    A computer program for the steady state thermal-hydraulic analysis of horizontal steam generator PGV-1000 is presented. The program provides the capability to analyze steam generator PGV-1000 primary side flow and temperature distribution, primary side pressure drops, heat transfer between the primary and secondary sides and multidimensional heat flux distribution. A special attention is paid to the thermal-hydraulics of the secondary side. The code predicts 3-D distribution of the void fraction at the secondary side, mass redistribution under the submerged perforated sheet and the steam generator level profile. By means of developed computer program a detailed thermal-hydraulic study of the PGV-1000 has been carried out. A wide range of calculations has been performed and a set of important steam generator characteristics has been obtained. Some of them are presented in the paper. (orig.). 5 refs.

  6. Horizontal steam generator PGV-1000 thermal-hydraulic analysis

    International Nuclear Information System (INIS)

    Ubra, O.; Doubek, M.

    1995-01-01

    A computer program for the steady state thermal-hydraulic analysis of horizontal steam generator PGV-1000 is presented. The program provides the capability to analyze steam generator PGV-1000 primary side flow and temperature distribution, primary side pressure drops, heat transfer between the primary and secondary sides and multidimensional heat flux distribution. A special attention is paid to the thermal-hydraulics of the secondary side. The code predicts 3-D distribution of the void fraction at the secondary side, mass redistribution under the submerged perforated sheet and the steam generator level profile. By means of developed computer program a detailed thermal-hydraulic study of the PGV-1000 has been carried out. A wide range of calculations has been performed and a set of important steam generator characteristics has been obtained. Some of them are presented in the paper. (orig.)

  7. Horizontal steam generator PGV-1000 thermal-hydraulic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ubra, O [Skoda Company, Prague (Switzerland); Doubek, M [Czech Technical Univ., Prague (Switzerland)

    1996-12-31

    A computer program for the steady state thermal-hydraulic analysis of horizontal steam generator PGV-1000 is presented. The program provides the capability to analyze steam generator PGV-1000 primary side flow and temperature distribution, primary side pressure drops, heat transfer between the primary and secondary sides and multidimensional heat flux distribution. A special attention is paid to the thermal-hydraulics of the secondary side. The code predicts 3-D distribution of the void fraction at the secondary side, mass redistribution under the submerged perforated sheet and the steam generator level profile. By means of developed computer program a detailed thermal-hydraulic study of the PGV-1000 has been carried out. A wide range of calculations has been performed and a set of important steam generator characteristics has been obtained. Some of them are presented in the paper. (orig.). 5 refs.

  8. Concentrating PV/T Hybrid System for Simultaneous Electricity and Usable Heat Generation: A Review

    Directory of Open Access Journals (Sweden)

    Longzhou Zhang

    2012-01-01

    Full Text Available Photovoltaic (PV power generation is one of the attractive choices for efficient utilization of solar energy. Considering that the efficiency and cost of PV cells cannot be significantly improved in near future, a relatively cheap concentrator to replace part of the expensive solar cells could be used. The photovoltaic thermal hybrid system (PV/T, combining active cooling with thermal electricity and providing both electricity and usable heat, can enhance the total efficiency of the system with reduced cell area. The effect of nonuniform light distribution and the heat dissipation on the performance of concentrating PV/T was discussed. Total utilization of solar light by spectral beam splitting technology was also introduced. In the last part, we proposed an integrated compound parabolic collector (CPC plate with low precision solar tracking, ensuring effective collection of solar light with a significantly lowered cost. With the combination of beam splitting of solar spectrum, use of film solar cell, and active liquid cooling, efficient and full spectrum conversion of solar light to electricity and heat, in a low cost way, might be realized. The paper may offer a general guide to those who are interested in the development of low cost concentrating PV/T hybrid system.

  9. Probe branes thermalization in external electric and magnetic fields

    International Nuclear Information System (INIS)

    Ali-Akbari, M.; Ebrahim, H.; Rezaei, Z.

    2014-01-01

    We study thermalization on rotating probe branes in AdS 5 ×S 5 background in the presence of constant external electric and magnetic fields. In the AdS/CFT framework this corresponds to thermalization in the flavour sector in field theory. The horizon appears on the worldvolume of the probe brane due to its rotation in one of the sphere directions. For both electric and magnetic fields the behaviour of the temperature is independent of the probe brane dimension. We also study the open string metric and the fluctuations of the probe brane in such a set-up. We show that the temperatures obtained from open string metric and observed by the fluctuations are larger than the one calculated from the induced metric

  10. Exploring utility organization electricity generation, residential electricity consumption, and energy efficiency: A climatic approach

    International Nuclear Information System (INIS)

    Craig, Christopher A.; Feng, Song

    2017-01-01

    Highlights: • Study examined impact of electricity fuel sources and consumption on emissions. • 97.2% of variability in emissions explained by coal and residential electricity use. • Increasing cooling degree days significantly related to increased electricity use. • Effectiveness of state-level energy efficiency programs showed mixed results. - Abstract: This study examined the impact of electricity generation by fuel source type and electricity consumption on carbon emissions to assess the role of climatic variability and energy efficiency (EE) in the United States. Despite high levels of greenhouse gas emissions, residential electricity consumption continues to increase in the United States and fossil fuels are the primary fuel source of electricity generation. 97.2% of the variability in carbon emissions in the electricity industry was explained by electricity generation from coal and residential electricity consumption. The relationships between residential electricity consumption, short-term climatic variability, long-term climatic trends, short-term reduction in electricity from EE programs, and long-term trends in EE programs was examined. This is the first study of its nature to examine these relationships across the 48 contiguous United States. Inter-year and long-term trends in cooling degree days, or days above a baseline temperature, were the primary climatic drivers of residential electricity consumption. Cooling degree days increased across the majority of the United States during the study period, and shared a positive relationship with residential electricity consumption when findings were significant. The majority of electricity reduction from EE programs was negatively related to residential electricity consumption where findings were significant. However, the trend across the majority of states was a decrease in electricity reduction from EE while residential electricity consumption increased. States that successfully reduced consumption

  11. Centralized electricity generation in Africa

    International Nuclear Information System (INIS)

    Jaujay, J.

    2000-01-01

    In Africa, over 90 per cent of the suburban and rural populations do not have access to electricity, even if it represents the engine and consequence of change on the continent. A global approach represents the best way to meet the extensive needs of the continent. The author briefly reviewed the recent projects implemented in Africa to meet the increasing demand. Diesel generators were used to satisfy demand in small electrical sectors (less than 1000 MW), hydroelectricity or combustion turbines were used for medium electrical sectors (1000 to 5000 MW). A discussion of the technologies followed, touching on diesel electric stations and combustion turbines. Both methods meet environmental standards as they apply to emission control and noise control. The choice between the two technologies must be based on required unit power, site isolation, access to gas, and the cost of available combustibles. Hydroelectric power has great potential in the sub-Sahara region, and the challenges faced by each project are similar: difficulty in finding the required financing, meeting the environmental constraints, and the distribution of the energy. A modular nuclear reactor project for the generation of electricity is being developed by ESKOM Enterprises, in association with the British Nuclear Fuel Limited and PECCO and progress will be closely monitored. Decision makers must ensure that appropriate decisions are made in a reasonable time frame to allow sufficient time to develop a project to implementation. Demand requirements must be examined closely, technology adequately selected in order to come up with a financing plan. 4 tabs

  12. Renewable Electricity Futures Study. Volume 2. Renewable Electricity Generation and Storage Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Augustine, Chad [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bain, Richard [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chapman, Jamie [Texas Tech Univ., Lubbock, TX (United States); Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Drury, Easan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hall, Douglas G. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lantz, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Thresher, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sandor, Debra [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bishop, Norman A. [Knight Piesold, Denver, CO (United States); Brown, Stephen R. [HDR/DTA, Portland, ME (Untied States); Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Felker, Fort [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fernandez, Steven J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Goodrich, Alan C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hagerman, George [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Heath, Garvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Neil, Sean [Ocean Renewable Energy Coalition, Portland, OR (United States); Paquette, Joshua [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Young, Katherine [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2012-06-15

    The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%–90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT). Learn more at the RE Futures website. http://www.nrel.gov/analysis/re_futures/

  13. An Approach for Designing Thermal Management Systems for Electric and Hybrid Vehicle Battery Packs

    International Nuclear Information System (INIS)

    Pesaran, Ahmad A.; Keyser, Matthew; Burch, Steve

    1999-01-01

    If battery packs for electric vehicles (EVs) and hybrid electric vehicles (HEVs) are to operate effectively in all climates, thermal management of the packs is essential. In this paper, we will review a systematic approach for designing and evaluating battery pack thermal management systems. A thermal management system using air as the heat transfer medium is less complicated than a system using liquid cooling/heating. Generally, for parallel HEVs, an air thermal management system is adequate, whereas for EVs and series HEVs, liquid-based systems may be required for optimum thermal performance. Further information on battery thermal management can be found on the Web site www.ctts.nrel.gov/BTM

  14. Fabrication, thermal and electrical properties of polyphenylene sulphide/copper composites

    International Nuclear Information System (INIS)

    Goyal, R.K.; Kambale, K.R.; Nene, S.S.; Selukar, B.S.; Arbuj, S.; Mulik, U.P.

    2011-01-01

    Highlights: → Polyphenylene sulphide/copper composites show a low percolation threshold, i.e., about 6 vol% Cu. → Both pre- and post- glass transition coefficient of thermal expansion (CTE) of composites decreased significantly. → The microhardness was increased by more than 50% compared to pure PPS matrix. → The electrical conductivity was increased by about eight orders of magnitude for 18 vol% Cu composite. → Dielectric constant and dissipation factor of composites measured at MHz was increased to about 6-fold and 70-fold compared to PPS matrix. - Abstract: The thermal and electrical properties of high performance poly(phenylene sulphide) (PPS) composites reinforced up to 31 vol% Cu particles were investigated to be used as materials for electronic applications. The thermal stability and char yield of the composites increased significantly. Both pre- and post- glass transition coefficient of thermal expansion (CTE) of composites decreased significantly. The microhardness was increased by more than 50% compared to pure PPS matrix. Microhardness and CTE of composites correlated well with the rule of mixtures. A percolation threshold about 6 vol% Cu was obtained. The electrical conductivity was increased by about eight orders of magnitude for 18 vol% composite. Dielectric constant and dissipation factor of composites at 1 MHz was increased by about 6-fold and 70-fold compared to matrix, respectively. They decreased gradually with increasing frequency up to 1 MHz and thereafter, there was insignificant change. The scanning electron microscope showed almost uniform distribution of Cu particles in the matrix. Owing to better dimensional stability and good electrical properties, these composites are very promising for electronic applications.

  15. Implementation of optimum solar electricity generating system

    International Nuclear Information System (INIS)

    Singh, Balbir Singh Mahinder; Karim, Samsul Ariffin A.; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep

    2014-01-01

    Under the 10 th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels

  16. Implementation of optimum solar electricity generating system

    Science.gov (United States)

    Singh, Balbir Singh Mahinder; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep; Karim, Samsul Ariffin A.

    2014-10-01

    Under the 10th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

  17. Implementation of optimum solar electricity generating system

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Balbir Singh Mahinder, E-mail: balbir@petronas.com.my; Karim, Samsul Ariffin A., E-mail: samsul-ariffin@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia); Sivapalan, Subarna, E-mail: subarna-sivapalan@petronas.com.my [Department of Management and Humanities, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia); Najib, Nurul Syafiqah Mohd; Menon, Pradeep [Department of Electrical and Electronics Engineering, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia)

    2014-10-24

    Under the 10{sup th} Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

  18. Characterization of a photovoltaic-thermal module for Fresnel linear concentrator

    International Nuclear Information System (INIS)

    Chemisana, D.; Ibanez, M.; Rosell, J.I.

    2011-01-01

    Highlights: → A combined domed Fresnel lens - CPC PVT system is designed and characterized. → Electrical and thermal experiments have been performed. → CFD analysis has been used to determine thermal characteristic dimensionless numbers. - Abstract: An advanced solar unit is designed to match the needs of building integration and concentrating photovoltaic/thermal generation. The unit proposed accurately combines three elements: a domed linear Fresnel lens as primary concentrator, a compound parabolic reflector as secondary concentrator and a photovoltaic-thermal module. In this work the photovoltaic-thermal generator is built, analysed and characterized. Models for the electrical and thermal behaviour of the module are developed and validated experimentally. Applying a thermal resistances approach the results from both models are combined. Finally, efficiency electrical and thermal curves are derived from theoretical analysis showing good agreement with experimental measurements.

  19. Thermal Energy Storage for Building Load Management: Application to Electrically Heated Floor

    Directory of Open Access Journals (Sweden)

    Hélène Thieblemont

    2016-07-01

    Full Text Available In cold climates, electrical power demand for space conditioning becomes a critical issue for utility companies during certain periods of the day. Shifting a portion or all of it to off-peak periods can help reduce peak demand and reduce stress on the electrical grid. Sensible thermal energy storage (TES systems, and particularly electrically heated floors (EHF, can store thermal energy in buildings during the off-peak periods and release it during the peak periods while maintaining occupants’ thermal comfort. However, choosing the type of storage system and/or its configuration may be difficult. In this paper, the performance of an EHF for load management is studied. First, a methodology is developed to integrate EHF in TRNSYS program in order to investigate the impact of floor assembly on the EHF performance. Then, the thermal comfort (TC of the night-running EHF is studied. Finally, indicators are defined, allowing the comparison of different EHF. Results show that an EHF is able to shift 84% of building loads to the night while maintaining acceptable TC in cold climate. Moreover, this system is able to provide savings for the customer and supplier if there is a significant difference between off-peak and peak period electricity prices.

  20. PID temperature controller in pig nursery: improvements in performance, thermal comfort, and electricity use.

    Science.gov (United States)

    de Souza Granja Barros, Juliana; Rossi, Luiz Antonio; Sartor, Karina

    2016-08-01

    The use of smarter temperature control technologies in heating systems can optimize the use of electric power and performance of piglets. Two control technologies of a resistive heating system were assessed in a pig nursery: a PID (proportional, integral, and derivative) controller and a thermostat. The systems were evaluated regarding thermal environment, piglet performance, and use of electric power for 99 days. The heating system with PID controller improved the thermal environment conditions and was significantly (P PID-controlled heating system is more efficient in electricity use and provides better conditions for thermal comfort and animal performance than heating with thermostat.

  1. Technological challenges in thermal plasma production

    International Nuclear Information System (INIS)

    Ramakrishnan, S.

    1995-01-01

    Thermal plasmas, generated by electric arc discharges, are used in a variety of industrial applications. The electric arc is a constricted electrical discharge with a high temperature in the range 6000-25,000 K. These characteristics are useful in plasma cutting, spraying, welding and specific areas of material processing. The thermal plasma technology is an enabling process technology and its status in the market depends upon its advantages over competing technologies. A few technological challenges to enhance the status of plasma technology are to improve the utilisation of the unique characteristics of the electric arc and to provide enhanced control of the process. In particular, new solutions are required for increasing the plasma-material interaction, controlling the electrode roots and controlling the thermal power generated by the arcing process. In this paper, the advantages of plasma technology, its constraints and future challenges for technology developments are highlighted. 36 refs., 14 figs

  2. Tuning the Electrical and Thermal Conductivities of Thermoelectric Oxides through Impurity Doping

    Science.gov (United States)

    Torres Arango, Maria A.

    Waste heat and thermal gradients available at power plants can be harvested to power wireless networks and sensors by using thermoelectric (TE) generators that directly transform temperature differentials into electrical power. Oxide materials are promising for TE applications in harsh industrial environments for waste heat recovery at high temperatures in air, because they are lightweight, cheaply produced, highly efficient, and stable at high temperatures in air. Ca3Co4O9(CCO) with layered structure is a promising p-type thermoelectric oxide with extrapolated ZT value of 0.87 in single crystal form [1]. However the ZT values for the polycrystalline ceramics remain low of ˜0.1-0.3. In this research, nanostructure engineering approaches including doping and addition of nanoinclusions were applied to the polycrystalline CCO ceramic to improve the energy conversion efficiency. Polycrystalline CCO samples with various Bi doping levels were prepared through the sol-gel chemical route synthesis of powders, pressing and sintering of the pellets. Microstructure features of Bi doped ceramic bulk samples such as porosity, development of crystal texture, grain boundary dislocations and segregation of Bi dopants at various grain boundaries are investigated from microns to atomic scale. The results of the present study show that the Bi-doping is affecting both the electrical conductivity and thermal conductivity simultaneously, and the optimum Bi doping level is strongly correlated with the microstructure and the processing conditions of the ceramic samples. At the optimum doping level and processing conditions of the ceramic samples, the Bi substitution of Ca results in the increase of the electrical conductivity, decrease of the thermal conductivity, and improvement of the crystal texture. The atomic resolution Scanning Transmission Electron Microscopy (STEM) Z-contrast imaging and the chemistry analysis also reveal the Bi-segregation at grain boundaries of CCO

  3. Electrohydrodynamic simulation of electrically controlled droplet generation

    International Nuclear Information System (INIS)

    Ouedraogo, Yun; Gjonaj, Erion; Weiland, Thomas; Gersem, Herbert De; Steinhausen, Christoph; Lamanna, Grazia; Weigand, Bernhard

    2017-01-01

    Highlights: • We develop a full electrohydrodynamic simulation approach which allows for the accurate modeling of droplet dynamics under the influence of transient electric fields. The model takes into account conductive, capacitive as well as convective electrical currents in the fluid. • Simulation results are shown for an electrically driven droplet generator using highly conductive acetone droplets and low conductivity pentane droplets, respectively. Excellent agreement with measurement is found. • We investigate the operation characteristic of the droplet generator by computing droplet sizes and detachment times with respect to the applied voltage. • The droplet charging effect is demonstrated for pentane droplets as well as for acetone droplets under long voltage pulses. We show that due to the very different relaxation times, the charging behavior of the two liquids is very different. • We demonstrate that due to this behavior, also the detachment mechanisms for acetone and pentane droplets are different. For low conductivity (pentane) droplets, droplet detachment is only possible after the electric fields are switched off. This is because the effective electric polarization force points upwards, thus, inhibiting the detachment of the droplet from the capillary tip. - Abstract: An electrohydrodynamic model for the simulation of droplet formation, detachment and motion in an electrically driven droplet generator is introduced. The numerical approach is based on the coupled solution of the multiphase flow problem with the charge continuity equation. For the latter, a modified convection-conduction model is applied, taking into account conductive, capacitive as well as convective electrical currents in the fluid. This allows for a proper description of charge relaxation phenomena in the moving fluid. In particular, the charge received by the droplet after detachment is an important parameter influencing the droplet dynamics in the test chamber

  4. Understanding social acceptance of electricity generation sources

    International Nuclear Information System (INIS)

    Bronfman, Nicolás C.; Jiménez, Raquel B.; Arévalo, Pilar C.; Cifuentes, Luis A.

    2012-01-01

    Social acceptability is a determinant factor in the failure or success of the government's decisions about which electricity generation sources will satisfy the growing demand for energy. The main goal of this study was to validate a causal trust-acceptability model for electricity generation sources. In the model, social acceptance of an energy source is directly caused by perceived risk and benefit and also by social trust in regulatory agencies (both directly and indirectly, through perceived risk and benefit). Results from a web-based survey of Chilean university students demonstrated that data for energy sources that are controversial in Chilean society (fossil fuels, hydro, and nuclear power) fit the hypothesized model, whereas data for non conventional renewable energy sources (solar, wind, geothermal and tidal) did not. Perceived benefit had the greatest total effect on acceptability, thus emerging as a key predictive factor of social acceptability of controversial electricity generation sources. Further implications for regulatory agencies are discussed. - Highlights: ► We tested a causal trust-acceptability model for electricity generation sources in Chile. ► Data for controversial energy sources in the Chilean society (fossil fuels, hydro and nuclear power) fit the hypothesized model. ► Data for non conventional renewable energy sources did not fit the data. ► Perceived benefit showed the greatest total effect on acceptability.

  5. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-08-03

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil -- by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines will be presented.

  6. Alberta electric industry annual statistics for 1998

    International Nuclear Information System (INIS)

    1999-06-01

    Tables containing data on electric energy generation and capacity for Alberta are provided for the following aspects: capacity and generation of power plants for 1998; capacity of power plants by type, unit, and energy resource for 1998; generating units approved for construction for 1998; generating units completed in 1998; transmission additions approved for construction and completed for 1998; net annual generating capacity and generation for 1988-1998; net monthly generation by plant for 1998; net annual generation by energy resource and type for 1988-1998; net monthly generation by energy resource and type for 1998; generation capacity reserve; relative capacity and generation by type of energy resource for 1998; capacity, generation and fuel consumption of isolated plants for 1998; other industrial on-site plant capacity and generation for 1998. Also listed are: energy resource consumption and energy conversion efficiency of thermal power plants for 1998; stack emissions from thermal generating plants for 1998; non-utility electric generators, wind and hydro for 1998; and hydroelectric energy utilization and conversion efficiency for 1998. Tables contain information on electric energy generation and capacity for hydroelectric energy stored in reservoirs in 1998; details of non-coincident net peak generation and load by utility operators for the Alberta electric system for 1998; and Alberta electric system generation and load at peak load hour for 1998. Further tables cover electric energy distribution for interchange and distribution for 1998 and 1981-1998; annual energy distribution to ultimate customers for 1988-1998 and to ultimate customers for 1998; and the number of electric utility customers in 1998. Final tables cover the transmission and distribution systems with data on: circuit km of such lines for 1988-1998; total circuit km of such lines by major electric utility for 1998 and number of rural electric utility customers for 1998

  7. Implementation of portfolio theory to the analysis of electricity generation in Mexico; Implementacion de la teoria del portafolio para el analisis de la generacion de energia electrica en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel E, J.; Ramirez S, J. R.; Palacios H, J. C., E-mail: jaime.esquivel@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    As part of the activities of economic analysis to the National Energy Strategy 2013-2027 of Mexico has been developed a computational platform to support decision-making based on the risk and performance in obtaining the optimum combination of technologies involved in the electricity generation. To this end, they consider five technologies: combined cycle, thermal coal, nuclear, hydro and wind. Each technology has been analyzed independently based on the total cost of generation level (given in dl s/KWh or dl s/MWh), leaning on documents as the Poise 2012-2026 and COPAR 2013. Subsequently by portfolio theory proposed by Markowitz, that combination of technologies that provide a greater benefit in the electricity generation is determined. In this study we consider two base work areas on which the proposed portfolios are reflected. The conformation of work areas is derived from the National Energy Strategy 2013-2027, considering a scenario with fossil technologies (combined cycle, thermal coal and nuclear) and other, making greater emphasis on the use of renewable technologies (combined cycle, hydro and wind). Finally, four portfolios are presented, each one with different percentages of ownership of technology in electricity generation, verifying the risk and performance of each combination. Of the analyzed portfolios, one corresponds to the mix of technologies which are currently in the country. The remaining derive the percentage share of combined-cycle technology, by subtracting 10% of their contribution and distributing it in three ways: by increasing the 10% share of nuclear technology; increasing 10% contribution of thermal coal technology and finally, extending the 5% of the electricity generation of nuclear technology and 5% increase in the electricity generation by wind technology. (Author)

  8. Electricity Generation Baseline Report

    Energy Technology Data Exchange (ETDEWEB)

    Logan, Jeffrey [National Renewable Energy Lab. (NREL), Golden, CO (United States); Marcy, Cara [National Renewable Energy Lab. (NREL), Golden, CO (United States); McCall, James [National Renewable Energy Lab. (NREL), Golden, CO (United States); Flores-Espino, Francisco [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bloom, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Aabakken, Jorn [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cole, Wesley [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jenkin, Thomas [National Renewable Energy Lab. (NREL), Golden, CO (United States); Porro, Gian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Liu, Chang [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ganda, Francesco [Argonne National Lab. (ANL), Argonne, IL (United States); Boardman, Richard [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tarka, Thomas [National Energy Technology Lab. (NETL), Albany, OR (United States); Brewer, John [National Energy Technology Lab. (NETL), Albany, OR (United States); Schultz, Travis [National Energy Technology Lab. (NETL), Albany, OR (United States)

    2017-01-01

    This report was developed by a team of national laboratory analysts over the period October 2015 to May 2016 and is part of a series of studies that provide background material to inform development of the second installment of the Quadrennial Energy Review (QER 1.2). The report focuses specifically on U.S. power sector generation. The report limits itself to the generation sector and does not address in detail parallel issues in electricity end use, transmission and distribution, markets and policy design, and other important segments. The report lists 15 key findings about energy system needs of the future.

  9. Is solar PV generated electricity cheap in South Africa?

    CSIR Research Space (South Africa)

    Roro, Kittessa T

    2015-07-01

    Full Text Available This presentation reflects on photovoltaic (PV) generated electricity in South Africa, and whether it is a cheaper alternative to current generated electricity in the country. It is projected that by 2019 the installed capacity of PV could...

  10. Third Generation Flywheels for electric storage

    Energy Technology Data Exchange (ETDEWEB)

    Ricci, Michael, R.; Fiske, O. James

    2008-02-29

    Electricity is critical to our economy, but growth in demand has saturated the power grid causing instability and blackouts. The economic penalty due to lost productivity in the US exceeds $100 billion per year. Opposition to new transmission lines and power plants, environmental restrictions, and an expected $100 billion grid upgrade cost have slowed system improvements. Flywheel electricity storage could provide a more economical, environmentally benign alternative and slash economic losses if units could be scaled up in a cost effective manner to much larger power and capacity than the present maximum of a few hundred kW and a few kWh per flywheel. The goal of this project is to design, construct, and demonstrate a small-scale third generation electricity storage flywheel using a revolutionary architecture scalable to megawatt-hours per unit. First generation flywheels are built from bulk materials such as steel and provide inertia to smooth the motion of mechanical devices such as engines. They can be scaled up to tens of tons or more, but have relatively low energy storage density. Second generation flywheels use similar designs but are fabricated with composite materials such as carbon fiber and epoxy. They are capable of much higher energy storage density but cannot economically be built larger than a few kWh of storage capacity due to structural and stability limitations. LaunchPoint is developing a third generation flywheel — the "Power Ring" — with energy densities as high or higher than second generation flywheels and a totally new architecture scalable to enormous sizes. Electricity storage capacities exceeding 5 megawatt-hours per unit appear both technically feasible and economically attractive. Our design uses a new class of magnetic bearing – a radial gap “shear-force levitator” – that we discovered and patented, and a thin-walled composite hoop rotated at high speed to store kinetic energy. One immediate application is power grid

  11. Morphology, thermal, electrical and electrochemical stability of nano

    Indian Academy of Sciences (India)

    In the present work, an attempt has been made to develop nano aluminium oxide (Al2O3)-filled polyvinyl alcohol (PVA) composite gel electrolytes. Surface morphological studies, thermal behaviour, electrochemical stability and electrical characterization of these composite gel electrolytes have been performed. An increase ...

  12. Electricity generation with natural gas or with uranium?

    International Nuclear Information System (INIS)

    Villanueva M, C.

    2009-10-01

    The program of works and investments of electric sector that actualize each year the Federal Commission of Electricity, include to the projects of electric power generating stations that will begin its commercial operation inside the horizon of the next ten years, in order to satisfy opportunely with appropriate reservation margins the demand of power and energy in the national interconnected system that grows year to year. In spite of its inherent advantages, in the electric sector prospective 2008-2017 are not considered explicitly to the nuclear power plants, except for the small amplification of capacity of nuclear power plant of Laguna Verde, that already is executing. In this context, the objective of this work is to present and to discuss arguments to favor and against the combined cycle and nuclear technologies, to indicate the risks and disadvantages in that it incurs the electric sector when leaning on so disproportionately on the fossil fuels for the electricity generation, in particular the natural gas, deferring to an indefinite future the installation of nuclear plants whose proven technology is economic, sure, clean and reliable and it contributes decisively to the national energy security. To mitigate the harmful effects of excessive dependence on natural gas to generate electric power, was propose alternatives to the expansion program of electric sector to year 2017, which would have as benefits the decrease of the annual total cost of electric power supply for public service, the significant reduction of natural gas imports and emissions reduction of CO 2 to the atmosphere. (Author)

  13. Peripapillary retinal thermal coagulation following electrical injury

    Directory of Open Access Journals (Sweden)

    Manjari Tandon

    2013-01-01

    Full Text Available In this study, we have presented the case report of a 20 year old boy who suffered an electric injury shock, following which he showed peripapillary retinal opacification and increased retinal thickening that subsequently progressed to retinal atrophy. The fluorescein angiogram revealed normal retinal circulation, thus indicating thermal damage to retina without any compromise to retinal circulation.

  14. Liberalization of power generation sector in the Croatian electricity market

    International Nuclear Information System (INIS)

    Viskovic, Alfredo

    2005-01-01

    The electricity market liberalization and the restructuring of power utilities eventually leads to the establishment of a single electricity market in Europe, which is especially important for efficiency gains in electricity generation coupled with increased security of supply, economic competitiveness and fulfillment of environmental requirements. The European electricity market Directives as well as the Energy Community Treaty for South East Europe (legislative Menu) have remarkable impact on the restructuring of the Croatian power sector and the development of electricity generation. The Croatian model of restructuring includes legal un bundling (in the ownership of one holding company - Hrvatska Elektroprivreda (HEP)). The operation of HEP Group and its subsidiaries in the conditions of partially opened electricity market in an important element that shapes the interactions of competitive activities and regulated activities in the environment influenced by exogenous factors a thirteen percent electricity are controlled by the Energy Market Operator (MO), the Transmission System Operator (TSO) and the Energy Regulatory Agency (CERA). The introduction of eligible procedures and newly created operative procedures for power system operation, are creating completely new conditions for competition in the power generation sector, where almost all power plants are owned by HEP. New generating capacities in Croatia can be built through tendering and licensing procedures carried out by the Regulator. Electricity prices are still regulated by the Government (below the cost reflective level), there is a small share of industrial consumers and the annual electricity production is 12 TWh, with relatively large share of hydro plants. All these have implications on the development of the power generation sector in Croatia as well as on electricity market operation. The subject matter of this paper is an impact of power system restructuring and electricity market opening on the

  15. Qualitative thermal characterization and cooling of lithium batteries for electric vehicles

    Science.gov (United States)

    Mariani, A.; D'Annibale, F.; Boccardi, G.; Celata, G. P.; Menale, C.; Bubbico, R.; Vellucci, F.

    2014-04-01

    The paper deals with the cooling of batteries. The first step was the thermal characterization of a single cell of the module, which consists in the detection of the thermal field by means of thermographic tests during electric charging and discharging. The purpose was to identify possible critical hot points and to evaluate the cooling demand during the normal operation of an electric car. After that, a study on the optimal configuration to obtain the flattening of the temperature profile and to avoid hot points was executed. An experimental plant for cooling capacity evaluation of the batteries, using air as cooling fluid, was realized in our laboratory in ENEA Casaccia. The plant is designed to allow testing at different flow rate and temperatures of the cooling air, useful for the assessment of operative thermal limits in different working conditions. Another experimental facility was built to evaluate the thermal behaviour changes with water as cooling fluid. Experimental tests were carried out on the LiFePO4 batteries, under different electric working conditions using the two loops. In the future, different type of batteries will be tested and the influence of various parameters on the heat transfer will be assessed for possible optimal operative solutions.

  16. Qualitative thermal characterization and cooling of lithium batteries for electric vehicles

    International Nuclear Information System (INIS)

    Mariani, A; D'Annibale, F; Boccardi, G; Celata, G P; La Sapienza (Italy))" data-affiliation=" (University of Roma La Sapienza (Italy))" >Menale, C; La Sapienza (Italy))" data-affiliation=" (University of Roma La Sapienza (Italy))" >Bubbico, R; Vellucci, F

    2014-01-01

    The paper deals with the cooling of batteries. The first step was the thermal characterization of a single cell of the module, which consists in the detection of the thermal field by means of thermographic tests during electric charging and discharging. The purpose was to identify possible critical hot points and to evaluate the cooling demand during the normal operation of an electric car. After that, a study on the optimal configuration to obtain the flattening of the temperature profile and to avoid hot points was executed. An experimental plant for cooling capacity evaluation of the batteries, using air as cooling fluid, was realized in our laboratory in ENEA Casaccia. The plant is designed to allow testing at different flow rate and temperatures of the cooling air, useful for the assessment of operative thermal limits in different working conditions. Another experimental facility was built to evaluate the thermal behaviour changes with water as cooling fluid. Experimental tests were carried out on the LiFePO4 batteries, under different electric working conditions using the two loops. In the future, different type of batteries will be tested and the influence of various parameters on the heat transfer will be assessed for possible optimal operative solutions.

  17. Apparatus and method for thermal power generation

    International Nuclear Information System (INIS)

    Cohen, P.; Redding, A.H.

    1978-01-01

    An improved thermal power plant and method of power generation is described which minimizes thermal stress and chemical impurity buildup in the vaporizing component, particularly beneficial under loss of normal feed fluid and startup conditions. The invention is particularly applicable to a liquid metal fast breeder reactor plant

  18. Feasibility study of wind-generated electricity for rural applications in southwestern Ohio

    Science.gov (United States)

    Kohring, G. W.

    The parameters associated with domestic production of wind generated electricity for direct use by small farms and rural homes in the southwestern Ohio region are discussed. The project involves direct utility interfaced electricity generation from a horizontal axis, down-wind, fixed pitch, wind powered induction generator system. Goals of the project are to determine: the ability to produce useful amounts of domestic wind generated electricity in the southwestern Ohio region; economic justification for domestic wind generated electrical production; and the potential of domestic wind generated electricity for reducing dependence on non-renewable energy resources in the southwestern Ohio region.

  19. Managing Wind-based Electricity Generation and Storage

    Science.gov (United States)

    Zhou, Yangfang

    Among the many issues that profoundly affect the world economy every day, energy is one of the most prominent. Countries such as the U.S. strive to reduce reliance on the import of fossil fuels, and to meet increasing electricity demand without harming the environment. Two of the most promising solutions for the energy issue are to rely on renewable energy, and to develop efficient electricity storage. Renewable energy---such as wind energy and solar energy---is free, abundant, and most importantly, does not exacerbate the global warming problem. However, most renewable energy is inherently intermittent and variable, and thus can benefit greatly from coupling with electricity storage, such as grid-level industrial batteries. Grid storage can also help match the supply and demand of an entire electricity market. In addition, electricity storage such as car batteries can help reduce dependence on oil, as it can enable the development of Plug-in Hybrid Electric Vehicles, and Battery Electric Vehicles. This thesis focuses on understanding how to manage renewable energy and electricity storage properly together, and electricity storage alone. In Chapter 2, I study how to manage renewable energy, specifically wind energy. Managing wind energy is conceptually straightforward: generate and sell as much electricity as possible when prices are positive, and do nothing otherwise. However, this leads to curtailment when wind energy exceeds the transmission capacity, and possible revenue dilution when current prices are low but are expected to increase in the future. Electricity storage is being considered as a means to alleviate these problems, and also enables buying electricity from the market for later resale. But the presence of storage complicates the management of electricity generation from wind, and the value of storage for a wind-based generator is not entirely understood. I demonstrate that for such a combined generation and storage system the optimal policy does not

  20. Electrical stimulation vs thermal effects in a complex electromagnetic environment.

    Science.gov (United States)

    Paniagua, Jesús M; Rufo, Montaña; Jiménez, Antonio; Antolín, Alicia; Sánchez, Miguel

    2009-08-01

    Studies linking exposure to low levels of radiofrequencies with adverse health effects, notwithstanding their present apparent inconsistency, have contributed to a steady improvement in the quality of evaluating that exposure. In complex electromagnetic environments, with a multitude of emissions of different frequencies acting simultaneously, knowledge of the spectral content is fundamental to evaluating human exposure to non-ionizing radiation. In the present work, we quantify the most significant spectral components in the frequency band 0.5-2200 MHz in an urban area. The measurements were made with a spectrum analyzer and monopole, biconical, and log-periodic antennas. Power density levels were calculated separately for the medium wave, short wave, and frequency modulation radio broadcasting bands, and for the television and GSM, DCS, and UMTS mobile telephony bands. The measured levels were compared with the ICNIRP reference levels for exposure to multiple frequency sources for thermal effects and electrical stimulation. The results showed the criterion limiting exposure on the basis of preventing electrical stimulation of peripheral nerves and muscles to be stricter (exposure quotient 24.7 10(-4)) than that based on thermal considerations (exposure quotient 0.16 10(-4)). The bands that contribute most to the latter are short wave, with 46.2%, and mobile telephony with 32.6% of the total exposure. In a complex electromagnetic environment, knowledge of the radiofrequency spectrum is essential in order to quantify the contribution of each type of emission to the public's exposure. It is also necessary to evaluate the electrical effects as well as the thermal effects because the criterion to limit exposure on the basis of the effect of the electrical stimulation of tissues is stricter than that based on thermal effects.

  1. Electrical stimulation vs thermal effects in a complex electromagnetic environment

    International Nuclear Information System (INIS)

    Paniagua, Jesus M.; Rufo, Montana; Jimenez, Antonio; Antolin, Alicia; Sanchez, Miguel

    2009-01-01

    Studies linking exposure to low levels of radiofrequencies with adverse health effects, notwithstanding their present apparent inconsistency, have contributed to a steady improvement in the quality of evaluating that exposure. In complex electromagnetic environments, with a multitude of emissions of different frequencies acting simultaneously, knowledge of the spectral content is fundamental to evaluating human exposure to non-ionizing radiation. In the present work, we quantify the most significant spectral components in the frequency band 0.5-2200 MHz in an urban area. The measurements were made with a spectrum analyzer and monopole, biconical, and log-periodic antennas. Power density levels were calculated separately for the medium wave, short wave, and frequency modulation radio broadcasting bands, and for the television and GSM, DCS, and UMTS mobile telephony bands. The measured levels were compared with the ICNIRP reference levels for exposure to multiple frequency sources for thermal effects and electrical stimulation. The results showed the criterion limiting exposure on the basis of preventing electrical stimulation of peripheral nerves and muscles to be stricter (exposure quotient 24.7 10 -4 ) than that based on thermal considerations (exposure quotient 0.16 10 -4 ). The bands that contribute most to the latter are short wave, with 46.2%, and mobile telephony with 32.6% of the total exposure. In a complex electromagnetic environment, knowledge of the radiofrequency spectrum is essential in order to quantify the contribution of each type of emission to the public's exposure. It is also necessary to evaluate the electrical effects as well as the thermal effects because the criterion to limit exposure on the basis of the effect of the electrical stimulation of tissues is stricter than that based on thermal effects.

  2. Solar thermal power plants

    International Nuclear Information System (INIS)

    Schnatbaum, L.

    2009-01-01

    The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale. In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of the collector. The thermal energy thus generated is used for electricity generation in a steam turbine. Parabolic trough plants can be combined with thermal storage and fossil or biomass fired heat exchangers to generate electricity even when the sun is not shining. Solar Millennium AG in Erlangen has developed the first power plant of this kind in Europe. After two years of construction the plant started operation in Southern Spain in 2008. This one and its sister projects are important steps leading the way for the whole market. The paper also covers the technological challenges, the key components used and the research and development activities concerning this technology. Solar thermal power plants are ideal for covering peak and medium loads in power grids. In hybrid operation they can also cover base-load. The Solar Chimney power plant, another striking technology for the conversion of solar into electric energy, is described briefly. The paper concludes with a look at the future - the import of solar energy from the deserts of North Africa to central Europe. (author)

  3. Small turbogenerators for post power generation of non-utilized thermal energy; Kleine Turbogeneratoren zur Nachverstromung nicht genutzter Waermen

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Kristian; Redemann, Christian [LEViTEC GmbH, Lahnau (Germany); Priebe, Klaus-Peter [LTi ADATURB GmbH, Unna (Germany)

    2009-07-01

    Nowadays in Germany a huge offer of waste heat is available, which is not used adequately for the generation of effective energy like electricity and coldness. This kind of heat is available through cogeneration units, combined heat and power stations, heat plants and process heat generation, operated by fossil or renewable energies. This unused waste heat achieves several 10.000 MW of thermal output, which accumulate in small installations with an output up to 1,0 MW primary energy insert. (orig.)

  4. Global Assessment of Hydrogen Technologies – Task 5 Report Use of Fuel Cell Technology in Electric Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Fouad, Fouad H.; Peters, Robert W.; Sisiopiku, Virginia P.; Sullivan Andrew J.; Ahluwalia, Rajesh K.

    2007-12-01

    The purpose of this work was to assess the performance of high temperature membranes and observe the impact of different parameters, such as water-to-carbon ratio, carbon formation, hydrogen formation, efficiencies, methane formation, fuel and oxidant utilization, sulfur reduction, and the thermal efficiency/electrical efficiency relationship, on fuel cell performance. A 250 KW PEM fuel cell model was simulated [in conjunction with Argonne National Laboratory (ANL) with the help of the fuel cell computer software model (GCtool)] which would be used to produce power of 250 kW and also produce steam at 120oC that can be used for industrial applications. The performance of the system was examined by estimating the various electrical and thermal efficiencies achievable, and by assessing the effect of supply water temperature, process water temperature, and pressure on thermal performance. It was concluded that increasing the fuel utilization increases the electrical efficiency but decreases the thermal efficiency. The electrical and thermal efficiencies are optimum at ~85% fuel utilization. The low temperature membrane (70oC) is unsuitable for generating high-grade heat suitable for useful cogeneration. The high temperature fuel cells are capable of producing steam through 280oC that can be utilized for industrial applications. Increasing the supply water temperature reduces the efficiency of the radiator. Increasing the supply water temperature beyond the dew point temperature decreases the thermal efficiency with the corresponding decrease in high-grade heat utilization. Increasing the steam pressure decreases the thermal efficiency. The environmental impacts of fuel cell use depend upon the source of the hydrogen rich fuel used. By using pure hydrogen, fuel cells have virtually no emissions except water. Hydrogen is rarely used due to problems with storage and transportation, but in the future, the growth of a “solar hydrogen economy” has been projected

  5. Non-thermal plasma at atmospheric pressure for ozone generation and volatile organic compounds decomposition

    International Nuclear Information System (INIS)

    Pekarek, S.; Khun, J.

    2006-01-01

    The non-thermal plasma technologies based on electrical discharges play an important role in ecological applications. The classical corona discharge is however relatively low power discharge. With the aim to extend its current-voltage range we studied hollow needle-to-plate DC corona discharge enhanced by the flow of a gas through the needle electrode. With this type of the discharge we performed an extensive study of ozone generation and volatile organic compounds decomposition. We found that supply of air through the needle substantially increases current-voltage range of the discharge in comparison with classical pin-to-plate corona discharge. Consequently the ozone generation as well as toluene decomposition efficiency was increased (Authors)

  6. A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 1: Summary

    Science.gov (United States)

    Chamberlain, R. G.; McMaster, K. M.

    1981-10-01

    The utility owned solar electric system methodology is generalized and updated. The net present value of the system is determined by consideration of all financial benefits and costs (including a specified return on investment). Life cycle costs, life cycle revenues, and residual system values are obtained. Break even values of system parameters are estimated by setting the net present value to zero. While the model was designed for photovoltaic generators with a possible thermal energy byproduct, it applicability is not limited to such systems. The resulting owner-dependent methodology for energy generation system assessment consists of a few equations that can be evaluated without the aid of a high-speed computer.

  7. A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 1: Summary

    Science.gov (United States)

    Chamberlain, R. G.; Mcmaster, K. M.

    1981-01-01

    The utility owned solar electric system methodology is generalized and updated. The net present value of the system is determined by consideration of all financial benefits and costs (including a specified return on investment). Life cycle costs, life cycle revenues, and residual system values are obtained. Break even values of system parameters are estimated by setting the net present value to zero. While the model was designed for photovoltaic generators with a possible thermal energy byproduct, it applicability is not limited to such systems. The resulting owner-dependent methodology for energy generation system assessment consists of a few equations that can be evaluated without the aid of a high-speed computer.

  8. Proposal of electric power generation from generators to water edge in the region of Sarapiqui

    International Nuclear Information System (INIS)

    Rodriguez Fallas, Cindy Veronica

    2013-01-01

    A proposed electric power generation is developed from generators to water edge in the region of Sarapiqui. The environmental characteristics, such as the hydrological network, hydrogeology, soil type, life zones, climatology, precipitation, temperature, evapotranspiration and water supply and demand, of rivers crossed by basin in the region of Sarapiqui, are determined by bibliographic consultations to implement the proposal. The most recent production statistics of the electric subsector of Costa Rica are described to reveal the growing annual demand and need for satisfaction. The zone of Sarapiqui is diagnosed as the right place to allow the generation of electric power from generators to water edge [es

  9. Techno-economic and environmental analysis of a thermal treatment technology for the generation of electrical energy by municipal solid waste from the zone of Los Santos

    International Nuclear Information System (INIS)

    Carranza Campos, Kevin; Monge Leiva, Matias

    2014-01-01

    A technical, economic and environmental assessment is realized of a thermal treatment technology. The energetic valorization from municipal solid waste and electric power generation in the zone of Los Santos, Costa Rica, are made by the multicriteria hierarchical analysis methodology. The national and cantonal situation is examined in the integral management of municipal solid waste (GIRS), with emphasis on the cantons from the zone of Los Santos. A comparative analysis is developed among some cantons of Costa Rica that have had GIRS studies, and the zone of Los Santos to know the fraction of municipal solid waste that can be valued energetically and calorific power that present. The similarity in the characterization, composition and physico-chemical properties is determined in the study of residues between the cantons analyzed and the zone of Los Santos. The legislation relating the waste processing is analyzed, according Law 8839 for integral management of waste and laws similar to the implementation of a power generation plant. An analysis is developed for the environmental compliance of thermal treatment technologies, including aspects for control of contaminants. The main technologies of energy valorization from waste are investigated and some real cases of Latin America and the world are exposed. A thermal treatment technology of municipal solid waste is selected through a decision-making methodology to evaluate technical, environmental and economic aspects. Operation requirements and functioning of the devices that conform a power generation plant are described by municipal solid waste of the technology selected. The economic viability of the selected proposal has determined by an economic analysis, to extend on the most influential aspects developing alternative scenarios. The diagnosis of the situation of solid waste in the zone of Los Santos has specified that the cardboard, paper and plastics have been the most adequate for the thermal utilization

  10. Distributed Generation of Electricity and its Environmental Impacts

    Science.gov (United States)

    Distributed generation refers to technologies that generate electricity at or near where it will be used. Learn about how distributed energy generation can support the delivery of clean, reliable power to additional customers.

  11. Development of Tailorable Electrically Conductive Thermal Control Material Systems

    Science.gov (United States)

    Deshpande, M. S.; Harada, Y.

    1997-01-01

    The optical characteristics of surfaces on spacecraft are fundamental parameters in controlling its temperature. Passive thermal control coatings with designed solar absorptance and infrared emittance properties have been developed and have been in use for some time. In this total space environment, the coating must be stable and maintain its desired optical properties as well as mechanical properties for the course of the mission lifetime. The mission lifetimes are increasing and in our quest to save weight, newer substrates are being integrated which limit electrical grounding schemes. All of this has added to already existing concerns about spacecraft charging and related spacecraft failures or operational failures. The concern is even greater for thermal control surfaces that are very large. One way of alleviating such concerns is to design new thermal control material systems (TCMS) that can help to mitigate charging via providing charge leakage paths. The objective of this program was to develop two types of passive electrically conductive TCMS. The first was a highly absorbing/emitting black surface and the second was a low (alpha(sub s)/epsilon(sub N)) type white surface. The surface resistance goals for the black absorber was 10(exp 4) to 10(exp 9) Omega/square, and for the white surfaces it was 10(exp 6) to 10(exp 10) Omega/square. Several material system concepts were suggested and evaluated for space environment stability and electrical performance characterization. Our efforts in designing and evaluating these material systems have resulted in several developments. New concepts, pigments and binders have been developed to provide new engineering quality TCMS. Some of these have already found application on space hardware, some are waiting to be recognized by thermal designers, and some require further detailed studies to become state-of-the-art for future space hardware and space structures. Our studies on baseline state-of-the-art materials and

  12. A minimum achievable PV electrical generating cost

    International Nuclear Information System (INIS)

    Sabisky, E.S.

    1996-01-01

    The role and share of photovoltaic (PV) generated electricity in our nation's future energy arsenal is primarily dependent on its future production cost. This paper provides a framework for obtaining a minimum achievable electrical generating cost (a lower bound) for fixed, flat-plate photovoltaic systems. A cost of 2.8 $cent/kWh (1990$) was derived for a plant located in Southwestern USA sunshine using a cost of money of 8%. In addition, a value of 22 $cent/Wp (1990$) was estimated as a minimum module manufacturing cost/price

  13. Environmental evaluation of different forms of electric energy generation

    International Nuclear Information System (INIS)

    Guena, Ana Maria de Oliveira; Aquino, Afonso Rodrigues de

    2007-01-01

    The development and implementation of other forms of energy generation caused local changes, where they were installed, giving rise to environmental impacts. This work presents an evaluation about different forms of electrical energy generation and the environmental impacts relative to each one of them. Five forms of electric energy generation were considered: thermoelectric, nuclear, hydroelectric, wind and solar energy. The implementation and the development of the petroleum industry in the world and in Brazil are presented. The geology of the oil, its extraction and quality improvement, besides details of the functioning of three types of thermoelectric power plants - coal, gas and oil - are also discussed. The specific as well as the environmental impacts they have in common are highlighted. The impacts originated from the deactivation of each one of them are also pointed out. Once outlined the environmental impacts from each form of electric energy generation, they were correlated and compared considering the area of the power plant implantation, the generation capacity, the efficiency, the power and the cost per kW. There is no totally clean form of electric energy generation. There is, however, generation without emission of gases responsible for the green house effect. Therefore, all forms of energy generation are important for a country; in other words, the best situation is the diversity of the energy matrix. (author)

  14. Thermal modelling of Li-ion polymer battery for electric vehicle drive cycles

    Science.gov (United States)

    Chacko, Salvio; Chung, Yongmann M.

    2012-09-01

    Time-dependent, thermal behaviour of a lithium-ion (Li-ion) polymer cell has been modelled for electric vehicle (EV) drive cycles with a view to developing an effective battery thermal management system. The fully coupled, three-dimensional transient electro-thermal model has been implemented based on a finite volume method. To support the numerical study, a high energy density Li-ion polymer pouch cell was tested in a climatic chamber for electric load cycles consisting of various charge and discharge rates, and a good agreement was found between the model predictions and the experimental data. The cell-level thermal behaviour under stressful conditions such as high power draw and high ambient temperature was predicted with the model. A significant temperature increase was observed in the stressful condition, corresponding to a repeated acceleration and deceleration, indicating that an effective battery thermal management system would be required to maintain the optimal cell performance and also to achieve a full battery lifesapn.

  15. Thermal plasmas: fundamental aspects

    International Nuclear Information System (INIS)

    Fauchais, P.

    2005-01-01

    This article treats of thermal plasmas, i.e. mainly produced by electric arcs and RF discharges. Their main characteristic is that they are generated at a pressure close to the atmospheric pressure (between 10 4 and 10 6 Pa) and refer to the classical kinetics of the Boltzmann equation. Because of the pressure, the collisions between particles are numerous and ionization is mainly due to a thermal effect. They correspond to electron densities between 10 20 and 10 24 m -3 and temperatures between 6000 and 25000 K. In these plasmas, the electric fields and the average free trajectories are too weak to generate a ionization state by direct inelastic collision. Ionization is thus essentially a thermal phenomenon due to elastic collisions. This article presents: 1 - the particles present in a plasma: definition, energy states; 2 - characteristic data: collisions, average free path and collision cross-section, distribution function, ionization types, charged particles mobility inside an electric field, scattering, Debye length; 3 - plasmas at the thermodynamical equilibrium: conditions of equilibrium, calculation of composition, thermodynamic properties, transport properties, radiation; 4 - thermal plasmas away from equilibrium: conditions of non-equilibrium, calculation of plasma composition, calculation of transport properties, quenching phenomenon. (J.S.)

  16. Implantable power generation system utilizing muscle contractions excited by electrical stimulation.

    Science.gov (United States)

    Sahara, Genta; Hijikata, Wataru; Tomioka, Kota; Shinshi, Tadahiko

    2016-06-01

    An implantable power generation system driven by muscle contractions for supplying power to active implantable medical devices, such as pacemakers and neurostimulators, is proposed. In this system, a muscle is intentionally contracted by an electrical stimulation in accordance with the demands of the active implantable medical device for electrical power. The proposed system, which comprises a small electromagnetic induction generator, electrodes with an electrical circuit for stimulation and a transmission device to convert the linear motion of the muscle contractions into rotational motion for the magneto rotor, generates electrical energy. In an ex vivo demonstration using the gastrocnemius muscle of a toad, which was 28 mm in length and weighed 1.3 g, the electrical energy generated by the prototype exceeded the energy consumed for electrical stimulation, with the net power being 111 µW. It was demonstrated that the proposed implantable power generation system has the potential to replace implantable batteries for active implantable medical devices. © IMechE 2016.

  17. Evaluation of Electrical and Thermal Conductivity of Polymeric ...

    African Journals Online (AJOL)

    PROF HORSFALL

    ABSTRACT: This work being gingered by the big menace being posed on our environment by polymeric waste and it's rechanneling involved the studying of the electrical and thermal conductivities of the polymers PP, PE, PS and nylon66 doped with charcoal and graphite. Five grams of each polymer was mixed with ...

  18. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief

    International Nuclear Information System (INIS)

    Pérez, Juan J.; Pérez-Cajaraville, Juan J.; Muñoz, Víctor; Berjano, Enrique

    2014-01-01

    Purpose: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a “strip lesion” to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. Methods: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. Results: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m −1 ) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. Conclusions: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of thermal

  19. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief

    Energy Technology Data Exchange (ETDEWEB)

    Pérez, Juan J. [Instituto de Investigación Interuniversitario en Bioingeniería y Tecnología Orientada al Ser Humano, Universitat Politècnica de València, Valencia 46022 (Spain); Pérez-Cajaraville, Juan J. [Pain Unit and Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, University of Navarra, Pamplona 31008 (Spain); Muñoz, Víctor [Neurotherm Spain, Barcelona 08303 (Spain); Berjano, Enrique, E-mail: eberjano@eln.upv.es [Biomedical Synergy, Electronic Engineering Department, Universitat Politècnica de València 46022 (Spain)

    2014-07-15

    Purpose: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a “strip lesion” to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. Methods: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. Results: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m{sup −1}) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. Conclusions: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of

  20. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief.

    Science.gov (United States)

    Pérez, Juan J; Pérez-Cajaraville, Juan J; Muñoz, Víctor; Berjano, Enrique

    2014-07-01

    Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a "strip lesion" to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m(-1)) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of thermal damage zone dimension.

  1. Applied risk analysis to the future Brazilian electricity generation matrix

    Energy Technology Data Exchange (ETDEWEB)

    Maues, Jair; Fernandez, Eloi; Correa, Antonio

    2010-09-15

    This study compares energy conversion systems for the generation of electrical power, with an emphasis on the Brazilian energy matrix. The financial model applied in this comparison is based on the Portfolio Theory, developed by Harry Markowitz. The risk-return ratio related to the electrical generation mix predicted in the National Energy Plan - 2030, published in 2006 by the Brazilian Energy Research Office, is evaluated. The increase of non-traditional renewable energy in this expected electrical generating mix, specifically, residues of sugar cane plantations and wind energy, reduce not only the risk but also the average cost of the kilowatt-hour generated.

  2. Novel polymer composite having diamond particles and boron nitride platelets for thermal management of electric vehicle motors

    Science.gov (United States)

    Nakajima, Anri; Shoji, Atsushi; Yonemori, Kei; Seo, Nobuhide

    2016-02-01

    Thermal conductivities of silicone matrix polymers including fillers of diamond particles and/or hexagonal boron nitride (h-BN) platelets were systematically investigated in an attempt to find a thermal interface material (TIM) having high isotropic thermal conductivity and high electrical insulating ability to enable efficient heat dissipation from the motor coil ends of electric vehicles. The TIM with mixed fillers of diamond particles and h-BN platelets had a maximum thermal conductivity of 6.1 W m-1 K-1 that was almost isotropic. This is the highest value among the thermal conductivities of TIMs with silicone matrix polymer reported to date. The mechanism behind the thermal conductivity of the TIMs was also examined from the viewpoint of the change in the number of thermally conductive networks and/or a decrease in the thermal resistivity of junctions of neighboring diamond particles through the incorporation of h-BN platelets. The TIMs developed in this study will make it possible to manage the heat of electric motors and will help to popularize electric vehicles.

  3. Model and analysis of solar thermal generators to reduce the intermittency of photovoltaic systems with the use of spectrum splitting

    Science.gov (United States)

    Ayala, Silvana; Wu, Yuechen; Vorndran, Shelby; Santiago, Raphael P.; Kostuk, Raymond K.

    2015-09-01

    In this paper we introduce an approach to damping intermittency in photovoltaic (PV) system output due to fluctuations in solar illumination generated by use of a hybrid PV-thermal electric (TE) generation system. We describe the necessary constrains of the PV-TE system based on its thermodynamic characteristics. The basis for the approach is that the thermal time constant for the TE device is much longer than that of a PV cell. When used in combination with an optimized thermal storage device short periods of intermittency (several minutes) in PV output due to passing clouds can be compensated. A comparison of different spectrum splitting systems to efficiently utilize the incident solar spectrum between the PV and TE converters are also examined. The time-dependent behavior of a hybrid PV-TE converter with a thermal storage element is computed with SMARTS modeled irradiance data and compared to real weather and irradiation conditions for Tucson, Arizona.

  4. Oxygen transport membrane reactor based method and system for generating electric power

    Science.gov (United States)

    Kelly, Sean M.; Chakravarti, Shrikar; Li, Juan

    2017-02-07

    A carbon capture enabled system and method for generating electric power and/or fuel from methane containing sources using oxygen transport membranes by first converting the methane containing feed gas into a high pressure synthesis gas. Then, in one configuration the synthesis gas is combusted in oxy-combustion mode in oxygen transport membranes based boiler reactor operating at a pressure at least twice that of ambient pressure and the heat generated heats steam in thermally coupled steam generation tubes within the boiler reactor; the steam is expanded in steam turbine to generate power; and the carbon dioxide rich effluent leaving the boiler reactor is processed to isolate carbon. In another configuration the synthesis gas is further treated in a gas conditioning system configured for carbon capture in a pre-combustion mode using water gas shift reactors and acid gas removal units to produce hydrogen or hydrogen-rich fuel gas that fuels an integrated gas turbine and steam turbine system to generate power. The disclosed method and system can also be adapted to integrate with coal gasification systems to produce power from both coal and methane containing sources with greater than 90% carbon isolation.

  5. The Electrical Breakdown of Thin Dielectric Elastomers

    DEFF Research Database (Denmark)

    Zakaria, Shamsul Bin; Morshuis, Peter H. F.; Yahia, Benslimane Mohamed

    2014-01-01

    Dielectric elastomers are being developed for use in actuators, sensors and generators to be used in various applications, such as artificial eye lids, pressure sensors and human motion energy generators. In order to obtain maximum efficiency, the devices are operated at high electrical fields....... This increases the likelihood for electrical breakdown significantly. Hence, for many applications the performance of the dielectric elastomers is limited by this risk of failure, which is triggered by several factors. Amongst others thermal effects may strongly influence the electrical breakdown strength....... In this study, we model the electrothermal breakdown in thin PDMS based dielectric elastomers in order to evaluate the thermal mechanisms behind the electrical failures. The objective is to predict the operation range of PDMS based dielectric elastomers with respect to the temperature at given electric field...

  6. Effect of electrical pulse treatment on the thermal fatigue resistance of bionic compacted graphite cast iron processed in water

    International Nuclear Information System (INIS)

    Liu, Yan; Zhou, Hong; Su, Hang; Yang, Chunyan; Cheng, Jingyan; Zhang, Peng; Ren, Luquan

    2012-01-01

    Highlights: ► Electrical pulse treatment can reduce cracks on bionic units before thermal fatigue tests. ► Electrical pulse treatment can reduce crack sources during thermal fatigue tests. ► Thermal fatigue resistance of bionic units processed in water is enhanced. ► Thermal fatigue resistance of bionic CGI processed in water is improved. -- Abstract: In order to further enhance the thermal fatigue resistance of bionic compacted graphite cast iron (CGI) which is processed by laser in water, the electrical pulse treatment is applied to improve the thermal fatigue resistance of bionic units. The results show that the electrical pulse treatment causes the supersaturated carbon atoms located in the lattice of austenite to react with the iron atoms to form the Fe 3 C. The microstructures of the bionic units processed in water are refined by the electrical pulse treatment. The cracks on the bionic units are reduced by the electrical pulse treatment before the thermal fatigue tests; and during the tests, the thermal fatigue resistance of bionic units is therefore enhanced by reducing the crack sources. By this way, the thermal fatigue resistance of bionic CGI processed in water is improved.

  7. A novel approach to generate random surface thermal loads in piping

    Energy Technology Data Exchange (ETDEWEB)

    Costa Garrido, Oriol, E-mail: oriol.costa@ijs.si; El Shawish, Samir; Cizelj, Leon

    2014-07-01

    Highlights: • Approach for generating continuous and time-dependent random thermal fields. • Temperature fields simulate fluid mixing thermal loads at fluid–wall interface. • Through plane-wave decomposition, experimental temperature statistics are reproduced. • Validation of the approach with a case study from literature. • Random surface thermal loads generation for future thermal fatigue analyses of piping. - Abstract: There is a need to perform three-dimensional mechanical analyses of pipes, subjected to complex thermo-mechanical loadings such as the ones evolving from turbulent fluid mixing in a T-junction. A novel approach is proposed in this paper for fast and reliable generation of random thermal loads at the pipe surface. The resultant continuous and time-dependent temperature fields simulate the fluid mixing thermal loads at the fluid–wall interface. The approach is based on reproducing discrete fluid temperature statistics, from experimental readings or computational fluid dynamic simulation's results, at interface locations through plane-wave decomposition of temperature fluctuations. The obtained random thermal fields contain large scale instabilities such as cold and hot spots traveling at flow velocities. These low frequency instabilities are believed to be among the major causes of the thermal fatigue in T-junction configurations. The case study found in the literature has been used to demonstrate the generation of random surface thermal loads. The thermal fields generated with the proposed approach are statistically equivalent (within the first two moments) to those from CFD simulations results of similar characteristics. The fields maintain the input data at field locations for a large set of parameters used to generate the thermal loads. This feature will be of great advantage in future sensitivity fatigue analyses of three-dimensional pipe structures.

  8. A novel approach to generate random surface thermal loads in piping

    International Nuclear Information System (INIS)

    Costa Garrido, Oriol; El Shawish, Samir; Cizelj, Leon

    2014-01-01

    Highlights: • Approach for generating continuous and time-dependent random thermal fields. • Temperature fields simulate fluid mixing thermal loads at fluid–wall interface. • Through plane-wave decomposition, experimental temperature statistics are reproduced. • Validation of the approach with a case study from literature. • Random surface thermal loads generation for future thermal fatigue analyses of piping. - Abstract: There is a need to perform three-dimensional mechanical analyses of pipes, subjected to complex thermo-mechanical loadings such as the ones evolving from turbulent fluid mixing in a T-junction. A novel approach is proposed in this paper for fast and reliable generation of random thermal loads at the pipe surface. The resultant continuous and time-dependent temperature fields simulate the fluid mixing thermal loads at the fluid–wall interface. The approach is based on reproducing discrete fluid temperature statistics, from experimental readings or computational fluid dynamic simulation's results, at interface locations through plane-wave decomposition of temperature fluctuations. The obtained random thermal fields contain large scale instabilities such as cold and hot spots traveling at flow velocities. These low frequency instabilities are believed to be among the major causes of the thermal fatigue in T-junction configurations. The case study found in the literature has been used to demonstrate the generation of random surface thermal loads. The thermal fields generated with the proposed approach are statistically equivalent (within the first two moments) to those from CFD simulations results of similar characteristics. The fields maintain the input data at field locations for a large set of parameters used to generate the thermal loads. This feature will be of great advantage in future sensitivity fatigue analyses of three-dimensional pipe structures

  9. Enhanced thermoelectric efficiency via orthogonal electrical and thermal conductances in phosphorene.

    Science.gov (United States)

    Fei, Ruixiang; Faghaninia, Alireza; Soklaski, Ryan; Yan, Jia-An; Lo, Cynthia; Yang, Li

    2014-11-12

    Thermoelectric devices that utilize the Seebeck effect convert heat flow into electrical energy and are highly desirable for the development of portable, solid state, passively powered electronic systems. The conversion efficiencies of such devices are quantified by the dimensionless thermoelectric figure of merit (ZT), which is proportional to the ratio of a device's electrical conductance to its thermal conductance. In this paper, a recently fabricated two-dimensional (2D) semiconductor called phosphorene (monolayer black phosphorus) is assessed for its thermoelectric capabilities. First-principles and model calculations reveal not only that phosphorene possesses a spatially anisotropic electrical conductance, but that its lattice thermal conductance exhibits a pronounced spatial-anisotropy as well. The prominent electrical and thermal conducting directions are orthogonal to one another, enhancing the ratio of these conductances. As a result, ZT may reach the criterion for commercial deployment along the armchair direction of phosphorene at T = 500 K and is close to 1 even at room temperature given moderate doping (∼2 × 10(16) m(-2) or 2 × 10(12) cm(-2)). Ultimately, phosphorene hopefully stands out as an environmentally sound thermoelectric material with unprecedented qualities. Intrinsically, it is a mechanically flexible material that converts heat energy with high efficiency at low temperatures (∼300 K), one whose performance does not require any sophisticated engineering techniques.

  10. Thermal-hydraulic characteristic of the PGV-1000 steam generator

    International Nuclear Information System (INIS)

    Ubra, O.; Doubek, M.

    1995-01-01

    Horizontal steam generators are typical parts of nuclear power plants with pressure water reactor type VVER. By means of this computer program, a detailed thermal-hydraulic study of the horizontal steam generator PGV-1000 has been carried out and a special attention has been paid to the thermal-hydraulics of the secondary side. A set of important steam generator characteristics has been obtained and analyzed. Some of the interesting results of the analysis are presented in the paper. (author)

  11. Effects of water-emulsified fuel on a diesel engine generator's thermal efficiency and exhaust.

    Science.gov (United States)

    Syu, Jin-Yuan; Chang, Yuan-Yi; Tseng, Chao-Heng; Yan, Yeou-Lih; Chang, Yu-Min; Chen, Chih-Chieh; Lin, Wen-Yinn

    2014-08-01

    Water-emulsified diesel has proven itself as a technically sufficient improvement fuel to improve diesel engine fuel combustion emissions and engine performance. However, it has seldom been used in light-duty diesel engines. Therefore, this paper focuses on an investigation into the thermal efficiency and pollution emission analysis of a light-duty diesel engine generator fueled with different water content emulsified diesel fuels (WD, including WD-0, WD-5, WD-10, and WD-15). In this study, nitric oxide, carbon monoxide, hydrocarbons, and carbon dioxide were analyzed by a vehicle emission gas analyzer and the particle size and number concentration were measured by an electrical low-pressure impactor. In addition, engine loading and fuel consumption were also measured to calculate the thermal efficiency. Measurement results suggested that water-emulsified diesel was useful to improve the thermal efficiency and the exhaust emission of a diesel engine. Obviously, the thermal efficiency was increased about 1.2 to 19.9%. In addition, water-emulsified diesel leads to a significant reduction of nitric oxide emission (less by about 18.3 to 45.4%). However the particle number concentration emission might be increased if the loading of the generator becomes lower than or equal to 1800 W. In addition, exhaust particle size distributions were shifted toward larger particles at high loading. The consequence of this research proposed that the water-emulsified diesel was useful to improve the engine performance and some of exhaust emissions, especially the NO emission reduction. Implications: The accumulated test results provide a good basis to resolve the corresponding pollutants emitted from a light-duty diesel engine generator. By measuring and analyzing transforms of exhaust pollutant from this engine generator, the effects of water-emulsified diesel fuel and loading on emission characteristics might be more clear. Understanding reduction of pollutant emissions during the use

  12. BUILDOUT AND UPGRADE OF CENTRAL EMERGENCY GENERATOR SYSTEM, GENERATOR 3 AND 4 ELECTRICAL INSTALLATION

    Energy Technology Data Exchange (ETDEWEB)

    Gary D. Seifert; G. Shawn West; Kurt S. Myers; Jim Moncur

    2006-07-01

    SECTION 01000—SUMMARY OF WORK PART 1—GENERAL 1.1 SUMMARY The work to be performed under this project consists of providing the labor, equipment, and materials to perform "Buildout and Upgrade of Central Emergency Generator System, Generator 3 and 4 Electrical Installation" for the National Aeronautics and Space Administration at the Dryden Flight Research Center (NASA/DFRC), Edwards, California 93523. All modifications to existing substations and electrical distribution systems are the responsibility of the contractor. It is the contractor’s responsibility to supply a complete and functionally operational system. The work shall be performed in accordance with these specifications and the related drawings. The work of this project is defined by the plans and specifications contained and referenced herein. This work specifically includes but is not limited to the following: Scope of Work - Installation 1. Install all electrical wiring and controls for new generators 3 and 4 to match existing electrical installation for generators 1 and 2 and in accordance with drawings. Contractor shall provide as-built details for electrical installation. 2. Install battery charger systems for new generators 3 and 4 to match existing battery charging equipment and installation for generators 1 and 2. This may require exchange of some battery charger parts already on-hand. Supply power to new battery chargers from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. 3. Install electrical wiring for fuel/lube systems for new generators 3 and 4 to match existing installation for generators 1 and 2. Supply power to lube oil heaters and fuel system (day tanks) from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. Add any conduits necessary to

  13. Electrical and thermal conductivity of low temperature CVD graphene: the effect of disorder

    International Nuclear Information System (INIS)

    Vlassiouk, Ivan; Datskos, Panos; Smirnov, Sergei; Ivanov, Ilia; Hensley, Dale; Lavrik, Nickolay V; Fulvio, Pasquale F; Dai Sheng; Meyer, Harry; Chi Miaofang

    2011-01-01

    In this paper we present a study of graphene produced by chemical vapor deposition (CVD) under different conditions with the main emphasis on correlating the thermal and electrical properties with the degree of disorder. Graphene grown by CVD on Cu and Ni catalysts demonstrates the increasing extent of disorder at low deposition temperatures as revealed by the Raman peak ratio, I G /I D . We relate this ratio to the characteristic domain size, L a , and investigate the electrical and thermal conductivity of graphene as a function of L a . The electrical resistivity, ρ, measured on graphene samples transferred onto SiO 2 /Si substrates shows linear correlation with L a -1 . The thermal conductivity, K, measured on the same graphene samples suspended on silicon pillars, on the other hand, appears to have a much weaker dependence on L a , close to K ∼ L a 1/3 . It results in an apparent ρ ∼ K 3 correlation between them. Despite the progressively increasing structural disorder in graphene grown at lower temperatures, it shows remarkably high thermal conductivity (10 2 -10 3 W K -1 m -1 ) and low electrical (10 3 -3 x 10 5 Ω) resistivities suitable for various applications.

  14. Wind power. [electricity generation

    Science.gov (United States)

    Savino, J. M.

    1975-01-01

    A historical background on windmill use, the nature of wind, wind conversion system technology and requirements, the economics of wind power and comparisons with alternative systems, data needs, technology development needs, and an implementation plan for wind energy are presented. Considerable progress took place during the 1950's. Most of the modern windmills feature a wind turbine electricity generator located directly at the top of their rotor towers.

  15. Electric Generators and their Control for Large Wind Turbines

    DEFF Research Database (Denmark)

    Boldea, Ion; Tutelea, Lucian; Rallabandi, Vandana

    2017-01-01

    induction generator, the cage rotor induction generator, and the synchronous generator with DC or permanent magnet excitation. The operating principle, performance, optimal design, and the modeling and control of the machine-side converter for each kind of generator are adressed and evaluated. In view......The electric generator and its power electronics interface for wind turbines (WTs) have evolved rapidly toward higher reliability and reduced cost of energy in the last 40 years. This chapter describes the up-to-date electric generators existing in the wind power industry, namely, the doubly fed...... of the fact that individual power rating of WTs has increased to around 10 MW, generator design and control technologies required to reach this power rating are discussed....

  16. Electric machinery and drives in thermal power stations

    International Nuclear Information System (INIS)

    1974-01-01

    The following subjects were dealt with during the VDE meeting: 1) Requirements made by the electric network on the generators and their excitation equipment, and the influence thereof on their design; 2) requirements made by the power station process on the electric drives and the influence thereof on type and design; 3) requirements made on protective measures from the point of the electric power station machinery. (TK) [de

  17. Distributed Generation Dispatch Optimization under Various Electricity Tariffs

    OpenAIRE

    Firestone, Ryan; Marnay, Chris

    2007-01-01

    The on-site generation of electricity can offer building owners and occupiers financial benefits as well as social benefits such as reduced grid congestion, improved energy efficiency, and reduced greenhouse gas emissions. Combined heat and power (CHP), or cogeneration, systems make use of the waste heat from the generator for site heating needs. Real-time optimal dispatch of CHP systems is difficult to determine because of complicated electricity tariffs and uncertainty in CHP equipment...

  18. Role of Energy Storage with Renewable Electricity Generation

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, P.; Ela, E.; Kirby, B.; Milligan, M.

    2010-01-01

    Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as intermittent) output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction of its energy from these sources as well as the cost of reliably integrating large amounts of variable generation into the electric grid. In this report, we explore the role of energy storage in the electricity grid, focusing on the effects of large-scale deployment of variable renewable sources (primarily wind and solar energy).

  19. Environmental evaluation of different forms of electric energy generation

    International Nuclear Information System (INIS)

    Guena, Ana Maria de Oliveira

    2007-01-01

    Electric energy has an important function in the modem world; it is fundamental for progress and development. The electricity discovery allowed improvements in several areas: health, water and food supply, quality of life and sanitary conditions, and contributed also to the establishment of the capitalist and consumption society. The use of oil as an energy generation source was the impulse for the industrial revolution and machines, motors and generators were developed contributing to the progress This also brought the pollutant gases emission (CO 2 , CO, SO x and NO x ) and other substances that had contributed to the greenhouse effect, the ozone hole and the acid rain, modifying the balance of the planet. The development and implementation of other forms of energy generation caused local changes, where they were installed, giving rise to environmental impacts. This work presents an evaluation about different forms of electrical energy generation and the environmental impacts relative to each one of them. Five forms of electric energy generation were considered: thermoelectric, nuclear, hydroelectric, wind and solar energy. The implementation and the development of the petroleum industry in the world and in Brazil are presented. The geology of the oil, its extraction and quality improvement, besides details of the functioning of three types of thermoelectric power plants - coal, gas and oil - are also discussed. The specific as well as the environmental impacts they have in common are highlighted. The impacts originated from the deactivation of each one of them are also pointed out. The discovery and the development of nuclear energy in Brazil and in the world as well as the functioning of a nuclear power plant, the impacts generated by its operation and decommissioning are presented. The history, functioning and development of hydroelectric energy generation in Brazil, characterized by the great plants, are related to environmental aspects The environmental

  20. Is It Better to Burn or Bury Waste for Clean Electricity Generation?

    Science.gov (United States)

    The generation of electricity through renewables has increased 5% since 2002. Although considerably less prominent than solar and wind, the use of municipal solid waste (MSW) to generate electricity represents roughly 14 percent of U.S. non-hydro renewable electricity generation....

  1. Electrically and Thermally Insulated Joint for Liquid Nitrogen Transfer

    DEFF Research Database (Denmark)

    Rasmussen, Carsten; Jensen, Kim Høj; Holbøll, Joachim T.

    1999-01-01

    A prototype of a superconducting cable is currently under construction. The cable conductor is cooled by liquid nitrogen in order to obtain superconductivity. The peripheral cooling circuit is kept at ground potential. This requires a joint which insulates both electrically and thermally...

  2. The Relationship Between Electricity Price and Wind Power Generation in Danish Electricity Markets

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    of competitive electricity markets in some ways, is chosen as the studied power system. The relationship between the electricity price (both the spot price and the regulation price) and the wind power generation in an electricity market is investigated in this paper. The spot price, the down regulation price...... and the up regulation price generally decreases when the wind power penetration in the power system increases. The statistical characteristics of the spot price for different wind power penetration are analyzed. The findings of this paper may be useful for wind power generation companies to make the optimal...... bidding strategy and may be also useful for the optimal operation of modern power systems with high wind power penetrations....

  3. The expected environmental consequences and hazards of laser-fusion electric generating stations

    International Nuclear Information System (INIS)

    Devaney, J.J.; Pendergrass, J.H.

    The operation of an expected early form of a laser-fusion electric power plant is described and the hazards and the environmental effects of such a station are estimated. Possible environmental impacts and hazards to mankind can occur from nuclear excursions or explosions, nuclear weapon proliferation, loss of coolant accident (LOCA), tritium releases, chemical fires and accompanying releases of radioactivity or chemicals, induced radioactivity releases (other than tritium), radioactive waste disposal, lasers, normal electrical generation and steam plant effects, external intrusions, natural disasters, land use, resource and transportation use, thermal pollution, and air and water pollution. We find the principle environmental effects to be those of a medium size chemical plant. Electric, magnetic, steam, and radioactive hazards are of a lower order. Indeed in the event of extraordinary success in getting high temperatures and densities so that more difficult nuclear species can be reacted, such as protons with boron-11, there will be no radioactivity at all and also enormously lower hazardous chemical inventories. In our plant designs, for any fusion fuels, nuclear explosions (or even excursions beyond design limits) are not possible. (author)

  4. Assessment of generic solar thermal systems for large power applications: analysis of electric power generating costs for systems larger than 10 MWe

    Energy Technology Data Exchange (ETDEWEB)

    Apley, W.J.; Bird, S.P.; Brown, D.R.; Drost, M.K.; Fort, J.A.; Garrett-Price, B.A.; Patton, W.P.; Williams, T.A.

    1980-11-01

    Seven generic types of collectors, together with associated subsystems for electric power generation, were considered. The collectors can be classified into three categories: (1) two-axis tracking (with compound-curvature reflecting surfaces); (2) one-axis tracking (with single-curvature reflecting surfaces); and (3) nontracking (with low-concentration reflecting surfaces). All seven collectors were analyzed in conceptual system configurations with Rankine-cycle engines. In addition, two of the collectors were analyzed with Brayton-cycle engines, and one was analyzed with a Stirling-cycle engine. With these engine options, and the consideration of both thermal and electrical storage for the Brayton-cycle central receiver, 11 systems were formulated for analysis. Conceptual designs developed for the 11 systems were based on common assumptions of available technology in the 1990 to 2000 time frame. No attempt was made to perform a detailed optimization of each conceptual design. Rather, designs best suited for a comparative evaluation of the concepts were formulated. Costs were estimated on the basis of identical assumptions, ground rules, methodologies, and unit costs of materials and labor applied uniformly to all of the concepts. The computer code SOLSTEP was used to analyze the thermodynamic performance characteristics and energy costs of the 11 concepts. Year-long simulations were performed using meteorological and insolation data for Barstow, California. Results for each concept include levelized energy costs and capacity factors for various combinations of storage capacity and collector field size.

  5. Superconducting Electric Boost Pump for Nuclear Thermal Propulsion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A submersible, superconducting electric boost pump sized to meet the needs of future Nuclear Thermal Propulsion systems in the 25,000 lbf thrust range is proposed....

  6. Achieving 33% renewable electricity generation by 2020 in California

    International Nuclear Information System (INIS)

    Walmsley, Michael R.W.; Walmsley, Timothy G.; Atkins, Martin J.

    2015-01-01

    This paper investigates the impacts of California, USA reaching its renewable electricity target of 33%, excluding large hydro, by 2020, which is set out in the state's RPS (Renewable Portfolio Standard). The emerging renewable electricity mix in California and surrounding states which form the WECC (Western Electricity Coordination Council) is analysed using the CEPA (Carbon Emission Pinch Analysis) and EROI (Energy Return on Energy Invested) methodologies. The reduction in emissions with increased renewables is illustrated and the challenge of maintaining high EROI levels for renewable generation is examined for low and high electricity demand growth. Results demonstrate that wind and solar PV collectively form an integral part of California reaching the 33% renewables target by 2020. Government interventions of tax rebates and subsidies, net electricity metering and a four tiered electricity price have accelerated the uptake of electricity generation from wind and solar PV. Residential uptake of solar PV is also reducing overall California electricity grid demand. Emphasis on new renewable generation is stimulating development of affordable wind and solar technology in California which has the added benefit of enhancing social sustainability through improved employment opportunities at a variety of technical levels. - Highlights: • CA (California, USA) aims to achieve 33% renewable electricity sales by 2020. • Carbon Emission Pinch Analysis is applied to the case study of CA. • Energy Return on Energy Invested analysis shows impacts of renewable energy uptake. • Solar PV and wind are the most cost and energy efficiency renewable resources in CA. • State government intervention is needed to reach the 33% renewable electricity goal.

  7. Obstacles to the penetration of electric generation markets by natural gas

    International Nuclear Information System (INIS)

    Schleede, G.R.

    1992-01-01

    This paper reviews and compares the advantages and disadvantages that electric power generators have in generating electricity from a variety of fuel sources. It then goes on to emphasize the use of natural gas and how it can become more competitive in the electric generation field. The paper is based primarily on experiences by the author during his employment with the New England Electric System (NEES). The author reviews the source of electricity for this utility and describes the percentages of each fuel source. It then goes on to specifically discuss the planned natural gas-fired projects in the utility system. The paper outlines the NEES strategy of diversification with respect to gas suppliers and describes the important considerations it used when planning for electric generation with gas. These include determining pressure requirements needed by the gas distribution system when the gas-generators come on-line; determining the placement of the generators within the overall system (i.e. peak load facilities, base load facilities, etc.); contracting flexibility because of the need to vary the amount of gas taken; and the ability to manage pipeline capacity and gas supplies when they are not needed

  8. Thermal and electrical energy management in a PEMFC stack - An analytical approach

    Energy Technology Data Exchange (ETDEWEB)

    Pandiyan, S.; Jayakumar, K.; Rajalakshmi, N.; Dhathathreyan, K.S. [Centre for Fuel Cell Technology, ARC International (ARCI), 120, Mambakkam Main Road, Medavakkam, Chennai 601 302 (India)

    2008-02-15

    An analytical method has been developed to differentiate the electrical and thermal resistance of the PEM fuel cell assembly in the fuel cell operating conditions. The usefulness of this method lies in the determination of the electrical resistance based on the polarization curve and the thermal resistance from the mass balance. This method also paves way for the evaluation of cogeneration from a PEMFC power plant. Based on this approach, the increase in current and resistance due to unit change in temperature at a particular current density has been evaluated. It was observed that the internal resistance of the cell is dependent on the electrode fabrication process, which also play a major role in the thermal management of the fuel cell stack. (author)

  9. An examination of electricity generation by utility organizations in the Southeast United States

    International Nuclear Information System (INIS)

    Craig, Christopher A.; Feng, Song

    2016-01-01

    This study examined the impact of climatic variability on electricity generation in the Southeast United States. The relationship cooling degree days (CDD) and heating degree days (HDD) shared with electricity generation by fuel source was explored. Using seasonal autoregressive integrated weighted average (ARIMA) and seasonal simple exponentially smoothed models, retrospective time series analysis was run. The hypothesized relationship between climatic variability and total electricity generation was supported, where an ARIMA model including CDDs as a predictor explained 57.6% of the variability. The hypothesis that climatic variability would be more predictive of fossil fuel electricity generation than electricity produced by clean energy sources was partially supported. The ARIMA model for natural gas indicated that CDDS were the only predictor for the fossil fuel source, and that 79.4% of the variability was explained. Climatic variability was not predictive of electricity generation from coal or petroleum, where simple seasonal exponentially smoothed models emerged. However, HDDs were a positive predictor of hydroelectric electricity production, where 48.9% of the variability in the clean energy source was explained by an ARIMA model. Implications related to base load electricity from fossil fuels, and future electricity generation projections relative to extremes and climate change are discussed. - Highlights: • Models run to examine impact of climatic variability on electricity generation. • Cooling degree days explained 57.6% of variability in total electricity generation. • Climatic variability was not predictive of coal or petroleum generation. • Cooling degree days explained 79.4% of natural gas generation. • Heating degree days were predictive of nuclear and hydroelectric generation.

  10. Evaluation and Ranking of Geothermal Resources for Electrical Generation or Electrical Offset in Idaho, Montana, Oregon and Washington. Volume II.

    Energy Technology Data Exchange (ETDEWEB)

    Bloomquist, R. Gordon

    1985-06-01

    This volume contains appendices on: (1) resource assessment - electrical generation computer results; (2) resource assessment summary - direct use computer results; (3) electrical generation (high temperature) resource assessment computer program listing; (4) direct utilization (low temperature) resource assessment computer program listing; (5) electrical generation computer program CENTPLANT and related documentation; (6) electrical generation computer program WELLHEAD and related documentation; (7) direct utilization computer program HEATPLAN and related documentation; (8) electrical generation ranking computer program GEORANK and related documentation; (9) direct utilization ranking computer program GEORANK and related documentation; and (10) life cycle cost analysis computer program and related documentation. (ACR)

  11. Projected Costs of Generating Electricity

    International Nuclear Information System (INIS)

    Plante, J.

    1998-01-01

    Every 3 to 4 years, the NEA undertakes a study on projected costs of generating electricity in OECD countries. This started in 1983 and the last study (1997) has just be completed. All together 5 studies were performed, the first three dealing with nuclear and coal options, while the 1992 and 1997 included also the gas option. The goal of the study is to compare, country by country, generating costs of nuclear, coal-fired and gas-fired power plants that could be commissioned in the respondent countries by 2005-2010

  12. Nanostructure design for drastic reduction of thermal conductivity while preserving high electrical conductivity.

    Science.gov (United States)

    Nakamura, Yoshiaki

    2018-01-01

    The design and fabrication of nanostructured materials to control both thermal and electrical properties are demonstrated for high-performance thermoelectric conversion. We have focused on silicon (Si) because it is an environmentally friendly and ubiquitous element. High bulk thermal conductivity of Si limits its potential as a thermoelectric material. The thermal conductivity of Si has been reduced by introducing grains, or wires, yet a further reduction is required while retaining a high electrical conductivity. We have designed two different nanostructures for this purpose. One structure is connected Si nanodots (NDs) with the same crystal orientation. The phonons scattering at the interfaces of these NDs occurred and it depended on the ND size. As a result of phonon scattering, the thermal conductivity of this nanostructured material was below/close to the amorphous limit. The other structure is Si films containing epitaxially grown Ge NDs. The Si layer imparted high electrical conductivity, while the Ge NDs served as phonon scattering bodies reducing thermal conductivity drastically. This work gives a methodology for the independent control of electron and phonon transport using nanostructured materials. This can bring the realization of thermoelectric Si-based materials that are compatible with large scale integrated circuit processing technologies.

  13. Thermal and Arc Flash Analysis of Electric Motor Drives in Distribution Networks

    OpenAIRE

    Nikolovski, Srete; Mlakić, Dragan; Alibašić, Emir

    2017-01-01

    The paper presents thermal analysis and arc flash analysis taking care of protection relays coordination settings for electric motor drives connected to the electrical network. Power flow analysis is performed to check if there are any voltage and loading violation conditions in the system. Fault analysis is performed to check the short circuit values and compute arc flash energy dissipated at industrial busbars to eliminate damage to electrical equipment and electrical shocks and hazard to p...

  14. The effect of regulatory governance on efficiency of thermal power generation in India: A stochastic frontier analysis

    International Nuclear Information System (INIS)

    Ghosh, Ranjan; Kathuria, Vinish

    2016-01-01

    This paper investigates the impact of institutional quality – typified as regulatory governance – on the performance of thermal power plants in India. The Indian power sector was reformed in the early 1990s. However, reforms are effective only as much as the regulators are committed in ensuring that they are implemented. We hypothesize that higher the quality of regulation in a federal Indian state, higher is the efficiency of electric generation utilities. A translog stochastic frontier model is estimated using index of state-level independent regulation as one of the determinants of inefficiency. The dataset comprises a panel of 77 coal-based thermal power plants during the reform period covering over 70% of installed electricity generation capacity. The mean technical efficiency of 76.7% indicates there is wide scope for efficiency improvement in the sector. Results are robust to various model specifications and show that state-level regulators have positively impacted plant performance. Technical efficiency is sensitive to both unbundling of state utilities, and regulatory experience. The policy implication is that further reforms which empower independent regulators will have far reaching impacts on power sector performance. - Highlights: • The impact of regulatory governance on Indian generation efficiency is investigated. • Stochastic frontier analysis (SFA) on a panel dataset covering pre and post reform era. • Index of state-wise variation in regulation to explain inefficiency effects. • Results show improved but not very high technical efficiencies. • State-level regulation has positively impacted power plant performance.

  15. Expansion planning for electrical generating systems

    International Nuclear Information System (INIS)

    1984-01-01

    The guidebook outlines the general principles of electric power system planning in the context of energy and economic planning in general. It describes the complexities of electric system expansion planning that are due to the time dependence of the problem and the interrelation between the main components of the electric system (generation, transmission and distribution). Load forecasting methods are discussed and the principal models currently used for electric system expansion planning presented. Technical and economic information on power plants is given. Constraints imposed on power system planning by plant characteristics (particularly nuclear power plants) are discussed, as well as factors such as transmission system development, environmental considerations, availability of manpower and financial resources that may affect the proposed plan. A bibliography supplements the references that appear in each chapter, and a comprehensive glossary defines terms used in the guidebook

  16. Helio-thermal energy generation: a new option of clean energy generation for Brazil

    International Nuclear Information System (INIS)

    Cavalcanti, Evando Sergio Camelo; Brito, Rubem Bastos Sanches de

    1999-01-01

    This work analyses the three most developed helio-thermal technologies, as follows: parabolic cylinder, central tower and parabolic disk. The electric power demand for the region is forecasted to be approximately 4,500-7,500 MW, in accordance with the type of used irrigation technology and the distance to the source

  17. Electricity markets evolution with the changing generation mix: An empirical analysis based on China 2050 High Renewable Energy Penetration Roadmap

    International Nuclear Information System (INIS)

    Zou, Peng; Chen, Qixin; Yu, Yang; Xia, Qing; Kang, Chongqing

    2017-01-01

    Highlights: • How electricity markets are evolving with the changing generation mix is studied. • China 2050 High Renewable Energy Penetration Roadmap are empirically analysed. • A multi-period Nash-Cournot model is established to study the market equilibrium. • Energy storages are analysed and compared to reveal their impacts on the equilibrium. - Abstract: The power generation mix are significantly changing due to the growth of stricter energy policies. The renewables are increasingly penetrating the power systems and leading to more clean energy and lower energy prices. However, they also require much more flexibilities and ancillary services to handle their uncertainties and variabilities. Thus, the requirements for regulation and reserve services may dramatically increase while the supplies of these services, which are mainly from the traditional thermal plants, remain almost invariant. This changing situation will cause higher regulation and reserve prices and impact the profit models and revenue structures of the traditional plants. How electricity markets are actually evolving with the changing generation mix? Can enough backup power plants be given adequate economic incentives and thus remained with the increasing renewables and the decreasing energy prices and productions? Can de-carbonization be fully performed in power systems? To explicitly answer the question, this paper uses a multi-period Nash-Cournot equilibrium model to formulate the evolution of power markets incorporating different types of generators, including thermal units, hydro units, wind farms, solar stations and energy storage systems. The price changes in the co-optimized energy, regulation and reserve markets, and the profit changes of various generators are studied. And the variabilities and uncertainties of renewable generation sources are considered in dynamically determining the requirements of regulation and reserve services. Based on the China 2050 High Renewable Energy

  18. Assessment of the once-through cooling alternative for central steam-electric generating stations

    Energy Technology Data Exchange (ETDEWEB)

    Paddock, R. A.; Ditmars, J. D.

    1978-12-01

    The efficacy of the disposal of waste heat from steam-electric power generation by means of once-through cooling systems was examined in the context of the physical aspects of water quality standards and guidelines for thermal discharges. Typical thermal standards for each of the four classes of water bodies (rivers, lakes, estuaries, and coastal waters) were identified. The mixing and dilution characteristics of various discharge modes ranging from simple, shoreline surface discharges to long, submerged multiport diffusers were examined in terms of the results of prototype measurements, analytical model predictions, and physical model studies. General guidelines were produced that indicate, for a given plant capacity, a given type of receiving water body, and a given discharge mode, the likelihood that once-through cooling can be effected within the restrictions of typical thermal standards. In general, it was found that shoreline surface discharges would not be adequate for large power plants (greater than or equal to 500 MW) at estuarine and marine coastal sites, would be marginally adequate at lake sites, and would be acceptable only at river sites with large currents and river discharges. Submerged multiport diffusers were found to provide the greatest likelihood of meeting thermal standards in all receiving water environments.

  19. Assessment of the once-through cooling alternative for central steam-electric generating stations

    International Nuclear Information System (INIS)

    Paddock, R.A.; Ditmars, J.D.

    1978-12-01

    The efficacy of the disposal of waste heat from steam-electric power generation by means of once-through cooling systems was examined in the context of the physical aspects of water quality standards and guidelines for thermal discharges. Typical thermal standards for each of the four classes of water bodies (rivers, lakes, estuaries, and coastal waters) were identified. The mixing and dilution characteristics of various discharge modes ranging from simple, shoreline surface discharges to long, submerged multiport diffusers were examined in terms of the results of prototype measurements, analytical model predictions, and physical model studies. General guidelines were produced that indicate, for a given plant capacity, a given type of receiving water body, and a given discharge mode, the likelihood that once-through cooling can be effected within the restrictions of typical thermal standards. In general, it was found that shoreline surface discharges would not be adequate for large power plants (greater than or equal to 500 MW) at estuarine and marine coastal sites, would be marginally adequate at lake sites, and would be acceptable only at river sites with large currents and river discharges. Submerged multiport diffusers were found to provide the greatest likelihood of meeting thermal standards in all receiving water environments

  20. Optimization of a waste heat recovery system with thermoelectric generators by three-dimensional thermal resistance analysis

    International Nuclear Information System (INIS)

    Huang, Gia-Yeh; Hsu, Cheng-Ting; Fang, Chun-Jen; Yao, Da-Jeng

    2016-01-01

    Highlights: • The waste heat recovery system is modeled by three-dimensional thermal resistance. • This is a time-saving and efficient method to estimate power generation from TEGs. • Relations between power generation and varied factors can be rapidly revealed. • TEGs positions and uniformity of velocity profile should be considered together. • Power generation is more sensitive to either internal or external flow velocity. - Abstract: Three-dimensional (3D) thermal resistance analysis provides a rapid and simple method to estimate the power generated from a waste heat recovery system with thermoelectric generators (TEGs), and facilitates an optimization of the system. Such a system comprises three parts – a waste heat recovery chamber, TEG modules and a cooling system. A fin-structured duct serves as a waste heat recovery chamber, which is attached to the hot sides of the TEGs; the cold sides of the TEGs are attached to a cooling system. The waste heat recovery chamber harvests energy from exhaust heat that the TEGs convert into electricity. The estimation of generated power is an important part of the system design. Methods of Computational Fluid Dynamics (CFD) assist the analysis and improve the performance with great accuracy but great computational duration. The use of this method saves much time relative to such CFD methods. In 3D thermal resistance analysis, a node of unknown temperature is located at the centroid of each cell into which the system is divided. The relations of unknown temperatures at the cells are based on the energy conservation and the definition of thermal resistance. The temperatures of inlet waste hot gas and ambient fluid are known. With these boundary conditions, the unknown temperatures in the system are solved, enabling estimation of the power generated with TEGs. A 3D model of the system was simulated with FloTHERM; its numerical solution matched the solution of the 3D thermal resistance analysis within 6%. The power

  1. Design and Testing of a Thermal Storage System for Electric Vehicle Cabin Heating

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Mingyu [MAHLE Behr Troy Inc.; WolfeIV, Edward [MAHLE Behr Troy Inc.; Craig, Timothy [MAHLE Behr Troy Inc.; LaClair, Tim J [ORNL; Gao, Zhiming [ORNL; Abdelaziz, Omar [ORNL

    2016-01-01

    Without the waste heat available from the engine of a conventional automobile, electric vehicles (EVs) must provide heat to the cabin for climate control using energy stored in the vehicle. In current EV designs, this energy is typically provided by the traction battery. In very cold climatic conditions, the power required to heat the EV cabin can be of a similar magnitude to that required for propulsion of the vehicle. As a result, the driving range of an EV can be reduced very significantly during winter months, which limits consumer acceptance of EVs and results in increased battery costs to achieve a minimum range while ensuring comfort to the EV driver. To minimize the range penalty associated with EV cabin heating, a novel climate control system that includes thermal energy storage has been designed for use in EVs and plug-in hybrid electric vehicles (PHEVs). The system uses the stored latent heat of an advanced phase change material (PCM) to provide cabin heating. The PCM is melted while the EV is connected to the electric grid for charging of the electric battery, and the stored energy is subsequently transferred to the cabin during driving. To minimize thermal losses when the EV is parked for extended periods, the PCM is encased in a high performance insulation system. The electrical PCM-Assisted Thermal Heating System (ePATHS) was designed to provide enough thermal energy to heat the EV s cabin for approximately 46 minutes, covering the entire daily commute of a typical driver in the U.S.

  2. Cost of electricity from small scale co-generation of electricity and heat

    Energy Technology Data Exchange (ETDEWEB)

    Kjellstroem, Bjoern

    2012-07-15

    There is an increasing interest in Sweden for using also small heat loads for cogeneration of electricity and heat. Increased use of small CHP-plants with heat supply capacities from a few 100 kW(h) up to 10 MW(h) cannot change the structure of the electricity supply system significantly, but could give an important contribution of 2 - 6 TWh(e) annually. The objective of this study was to clarify under what conditions electricity can be generated in small wood fired CHP-plants in Sweden at costs that can compete with those for plants using fossil fuels or nuclear energy. The capacity range studied was 2 - 10 MW(h). The results should facilitate decisions about the meaningfulness of considering CHP as an option when new heat supply systems for small communities or sawmills are planned. At the price for green certificates in Sweden, 250 - 300 SEK/MWh(e), generation costs in small wood fired CHP-plants should be below about 775 SEK/MWh(e) to compete with new nuclear power plants and below about 925 SEK/MWh(e) to compete with generation using fossil fuels.

  3. Thermal Performance of Motor and Inverter in an Integrated Starter Generator System for a Hybrid Electric Vehicle

    OpenAIRE

    Sung Chul Kim

    2013-01-01

    If the integrated starter generator (ISG) motor and inverter operate under continuously high loading conditions, the system’s performance and durability will decrease and the heat dissipation requirements will increase. Therefore, in this study, we developed two cooling designs for the ISG motor and inverter, and then carried out both a model analysis and an experiment on the fluid flow and thermal characteristics of the system under various operating conditions. As the outdoor temperature in...

  4. Impact of Auxiliary Equipments Consumption on Electricity Generation Cost in Selected Power Plants of Pakistan

    Directory of Open Access Journals (Sweden)

    DILEEP KUMAR

    2017-04-01

    Full Text Available This study focuses on higher generation cost of electricity in selected TPPs (Thermal Power Plants in Sindh, Pakistan. It also investigates the energy consumed by the auxiliary equipment of the selected TPPs in Sindh, Pakistan. The AC (Auxiliary Consumption of selected TPPs is compared with that in UK and other developed countries. Results show that the AC in selected TPPs in Sindh, Pakistan exceeds the average AC of the TPPs situated in developed countries. Many energy conservation measures such as impeller trimming and de-staging, boiler feed pump, high voltage inverter, variable frequency drive, and upgrading the existing cooling tower fan blades with fiber reinforced plastic are discussed to overcome higher AC. This study shows that harnessing various available energy conservative measures the AC and unit cost can be reduced by 4.13 and 8.8%; also adverse environmental impacts can be mitigated. Results show that the unit cost of electricity can be reduced from Rs.20 to19/kWh in JTPP (Jamshoro Thermal Power Plant, Rs.9 to 8.8/kWh in GTPS (Gas Turbine Power Station Kotri and Rs. 11 to 10.27/ kWh in LPS (Lakhara Power Station. Thus, electricity production can be improved with the existing capacity, which will eventually assist to manage the current energy crisis and ensure its conservation

  5. Survey of solar thermal energy storage subsystems for thermal/electric applications

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C. L.

    1978-08-01

    A survey of the current technology and estimated costs of subsystems for storing the thermal energy produced by solar collectors is presented. The systems considered were capable of producing both electricity and space conditioning for three types of loads: a single-family detached residence, an apartment complex of 100 units, and a city of 30,000 residents, containing both single-family residences and apartments. Collector temperatures will be in four ranges: (1) 100 to 250/sup 0/F (used for space heating and single-cycle air conditioners and organic Rankine low-temperature turbines); (2) 300 to 400/sup 0/F (used for dual-cycle air conditioners and low-temperature turbines); (3) 400 to 600/sup 0/F (using fluids from parabolic trough collectors to run Rankine turbines); (4) 800 to 1000/sup 0/F (using fluids from heliostats to run closed-cycle gas turbines and steam Rankine turbines). The solar thermal energy subsystems will require from 60 to 36 x 10/sup 5/ kWhr (2.05 x 10/sup 5/ to 1.23 x 10/sup 10/ Btu) of thermal storage capacity. In addition to sensible heat and latent heat storage materials, several other media were investigated as potential thermal energy storage materials, including the clathrate and semiclathrate hydrates, various metal hydrides, and heat storage based on inorganic chemical reactions.

  6. Generation adequacy report on the electricity supply-demand balance in France. 2016 edition + executive summary

    International Nuclear Information System (INIS)

    2016-01-01

    After a presentation of the elaboration framework of this generation adequacy report, and of the objectives of the risk analysis, this report proposes a detailed analysis of electricity consumption in France. It describes the main determining factors of electric power consumption: energy efficiency, economic growth, demography, and transfers and new uses of electricity. It proposes a sector-based analysis of energy demand (housing sector, office building sector, industrial sector, transport, energy and agriculture sectors), and an assessment of perspectives for power consumption. It also proposes a power-based analysis of electricity consumption: influence of temperature on electricity consumption, analysis of the load curve, perspectives for electricity consumption peak. The next part addresses the evolution of electricity supply in France. It presents the existing production fleet, proposes an overview of renewable energies (ground-based wind energy, offshore wind energy and marine energies, solar photovoltaic energy, bio-energies, hydraulic energy), presents some characteristics of the French nuclear fleet (installed capacity, availability), analyses the flame-based thermal fleet (oil-based, coal-based, gas-based combined, combustion turbine, and decentralised thermal installations). It also discusses the issue of load management, and proposes a synthetic overview of the electricity production fleet (supply evolutions on the medium term, evolutions with respect to the 2015 provisional assessment). The next chapter reports a risk analysis on the medium term by presenting indicators of supply safety, by proposing a failure risk analysis (diagnosis on the medium term, comparison with the previous provisional assessment, sensitivity to extreme events), by presenting energy assessments, by reporting sensitivity analysis (to consumption hypotheses, to hypotheses related to the development of renewable energies, to hypotheses related to the nuclear fleet), by reporting

  7. Electricity generation projections of the world and Brazil

    International Nuclear Information System (INIS)

    Dias, Marcio Soares

    2002-01-01

    The world use of electricity is projected to increase by 9,570 billions kWh over a span of 20 years. Natural gas is expected to account for the largest increment in electricity generation. As a result of high oil and natural gas consumption fuel prices are projected to rise in nominal dollars over the forecast horizon. Higher capacity utilisation and fewer expected retirements of running nuclear plants have resulted in a revision of EIA's projected consumption of electricity from nuclear power. Projection of 3.6%/year in the electricity consumption in Brazil is lower than the historical correlation given by the GDP (5%) growth rate plus 1.2 to 1.7%. GDP and energy consumption growth rates for Brazil are projected to be higher than the world value, but are lower than the projected values for countries like Mexico and China. Trends in primary fuel prices and external dependence on fuel supply are important factors for the Brazilian investments on electricity generation due their impact on costs and standard of living. (author)

  8. A Comparison of Electricity Generation System Sustainability among G20 Countries

    Directory of Open Access Journals (Sweden)

    Jinchao Li

    2016-12-01

    Full Text Available Planning for electricity generation systems is a very important task and should take environmental and economic factors into account. This paper reviews the existing metrics and methods in evaluating energy sustainability, and we propose a sustainability assessment index system. The input indexes include generation capacity, generation cost, and land use. The output indexes include desirable and undesirable parts. The desirable outputs are total electricity generation and job creation. The undesirable outputs are external supply risk and external costs associated with the environment and health. The super-efficiency data envelopment analysis method is used to calculate the sustainability of electricity generation systems of 23 countries from 2005 to 2014. The three input indexes and three undesirable output indexes are used as the input variables. The two desirable outputs are used as the output variables. The results show that most countries’ electricity generation sustainability values have decreasing trends. In addition, nuclear and hydro generation have positive effects. Solar, wind, and fossil fuel generation have negative effects on sustainability.

  9. Options of electric generation and sustainability

    International Nuclear Information System (INIS)

    Martin del Campo M, C.

    2004-01-01

    In this paper a study on the sustainability of the main electricity generation options is presented. The study is based on a matrix of sustainability indicators developed in Switzerland. A revision of some sustainability studies performed in countries with certain energy diversity and with experience in nuclear power plants operation, is done. Studies, in general, are performed for the power plant life cycle, taking into account economic aspects, fuel prices impact on electricity generation costs, fuel reserves indicators and material consumption. Air emission, waste production and human health impact data are also presented. All the results lead to confirm that nuclear energy has a high degree of sustainability vis a vis other options based on fossil fuels and renewable. Finally some comments are presented in order to highlight the importance that nuclear energy might have in the sustainable development of Mexico. (Author)

  10. Modelling the impact of EVs on electricity generation, costs and CO2 emissions

    International Nuclear Information System (INIS)

    Calnan, P.; Deane, J.P.; Ó Gallachóir, B.P.

    2013-01-01

    This paper focuses on the impact of electric vehicles on electricity generation in Ireland in 2025 based on five alternative generation portfolios. The year 2025 was selected for assessment due to the information on the composition of the five generation portfolios from Eirgrid the system operator in Ireland being provided. Detailed market simulations were undertaken on the five possible generation portfolios to assess the impact of the Government targets for electric vehicles on the generation costs, emissions, generation stack and the cost to load of this additional demand. This paper also studied the impact between a standard and least cost electric vehicle loading regime to ascertain the benefits that could be achieved. The results show that gas will be the dominant source of electricity generation to load electric vehicles and that wind as an electricity source will experience a minor reduction in curtailment, with the least cost charging profile showing a more pronounced reduction. The capital benefits of the Standard and Least Cost EV load are found to be negligible. The portfolios studied generated CO 2 emissions per kilometre between 52 and 70 gCO 2 /km. All portfolios with the exception of coal were found to comply with EU regulation 443/2009. - Highlights: • This paper focuses on the impact of electric vehicles on electricity generation in Ireland in 2025. • It uses the PLEXOS software package by Energy Exemplar to model the Irish electricity market. • Government targets for electric vehicle penetration have a limited impact on the power system. • Electric vehicles will meet EU requirements in terms of emissions created per kilometre

  11. Materials and design concerning magnetohydrodynamic channels of direct power conversion from combustion gases thermal energy into electricity

    International Nuclear Information System (INIS)

    Yerouchalmi, David

    1970-01-01

    Direct power conversion of thermal energy into electricity by magnetohydrodynamic is defined through thermodynamic cycles of hot gases; the present work concerning only the channel-generator operating with fossil gases in open cycle. Insulating walls and electrodes are subject initially to general apparent working conditions and those are followed by several others which appear only when experimental stage is reached. First, a choice has to be made between cold walls and hot walls which have been both closely investigated. But experience and theory lead to a third solution: viz controlled temperature walls and to consequent thermal exchange design. Many additional phenomena such as: solid state electrolysis, vaporisation, corrosion and alkali seed migration are analysed; then some solutions are described, tried and suggested. Same is given for mechanical, cooling devices, cold electric junctions and current relays. Experimental devices and work done on several solutions are described and results given. New prospects are suggested; and, in conclusion, the subject still appears to merit quite an important amount of further research. (author) [fr

  12. Improvements in steam cycle electric power generating plants

    International Nuclear Information System (INIS)

    Bienvenu, Claude.

    1973-01-01

    The invention relates to a steam cycle electric energy generating plants of the type comprising a fossil or nuclear fuel boiler for generating steam and a turbo alternator group, the turbine of which is fed by the boiler steam. The improvement is characterized in that use is made of a second energy generating group in which a fluid (e.g. ammoniac) undergoes a condensation cycle the heat source of said cycle being obtained through a direct or indirect heat exchange with a portion of the boiler generated steam whereby it is possible without overloading the turbo-alternator group, to accomodate any increase of the boiler power resulting from the use of another fuel while maintaining a maximum energy output. This can be applied to electric power stations [fr

  13. Electric power supply in Sweden 1979/80

    International Nuclear Information System (INIS)

    1981-01-01

    Generation, transmission and consumption of electricity for the year 1979/80 in Sweden are review in this report. The net supply of electricity in TWh was 60.2 from hydro, 20.1 from nuclear, 12.1 from fossil thermal and 1.4 imported. Detailed statistics are given for both consumption and generation. (L.E.)

  14. A predictive thermal dynamic model for parameter generation in the laser assisted direct write process

    International Nuclear Information System (INIS)

    Shang Shuo; Fearon, Eamonn; Wellburn, Dan; Sato, Taku; Edwardson, Stuart; Dearden, G; Watkins, K G

    2011-01-01

    The laser assisted direct write (LADW) method can be used to generate electrical circuitry on a substrate by depositing metallic ink and curing the ink thermally by a laser. Laser curing has emerged over recent years as a novel yet efficient alternative to oven curing. This method can be used in situ, over complicated 3D contours of large parts (e.g. aircraft wings) and selectively cure over heat sensitive substrates, with little or no thermal damage. In previous studies, empirical methods have been used to generate processing windows for this technique, relating to the several interdependent processing parameters on which the curing quality and efficiency strongly depend. Incorrect parameters can result in a track that is cured in some areas and uncured in others, or in damaged substrates. This paper addresses the strong need for a quantitative model which can systematically output the processing conditions for a given combination of ink, substrate and laser source; transforming the LADW technique from a purely empirical approach, to a simple, repeatable, mathematically sound, efficient and predictable process. The method comprises a novel and generic finite element model (FEM) that for the first time predicts the evolution of the thermal profile of the ink track during laser curing and thus generates a parametric map which indicates the most suitable combination of parameters for process optimization. Experimental data are compared with simulation results to verify the accuracy of the model.

  15. Renewable energy technologies for electricity generation

    International Nuclear Information System (INIS)

    Thorpe, T.W.

    1993-01-01

    The output of electricity supplied by some renewable sources cannot be easily predicted in advance because of their dependence on naturally varying phenomena (e.g. wind or sunshine). To accommodate this variability within the grid, additional amounts of conventional plant might be maintained in reserve, which would add to the overall system cost. This paper examines some aspects of renewable energy technologies for electricity generation as well as factors to be considered in the incorporation of renewables within a grid. 7 refs, 3 figs, 2 tabs

  16. Robust Control of Aeronautical Electrical Generators for Energy Management Applications

    OpenAIRE

    Giacomo Canciello; Alberto Cavallo; Beniamino Guida

    2017-01-01

    A new strategy for the control of aeronautical electrical generators via sliding manifold selection is proposed, with an associated innovative intelligent energy management strategy used for efficient power transfer between two sources providing energy to aeronautical loads, having different functionalities and priorities. Electric generators used for aeronautical application involve several machines, including a main generator and an exciter. Standard regulators (PI or PID-like) are normally...

  17. Coal-Powered Electric Generating Unit Efficiency and Reliability Dialogue: Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Emmanuel [Energetics, Inc., Columbia, MD (United States)

    2018-02-01

    Coal continues to play a critical role in powering the Nation’s electricity generation, especially for baseload power plants. With aging coal generation assets facing decreased performance due to the state of the equipment, and with challenges exacerbated by the current market pressures on the coal sector, there are opportunities to advance early-stage technologies that can retrofit or replace equipment components. These changes will eventually result in significant improvements in plant performance once further developed and deployed by industry. Research and development in areas such as materials, fluid dynamics, fuel properties and preparation characteristics, and a new generation of plant controls can lead to new components and systems that can help improve the efficiency and reliability of coal-fired power plants significantly, allowing these assets to continue to provide baseload power. Coal stockpiles at electricity generation plants are typically large enough to provide 30 to 60 days of power prior to resupply—significantly enhancing the stability and reliability of the U.S. electricity sector. Falling prices for non-dispatchable renewable energy and mounting environmental regulations, among other factors, have stimulated efforts to improve the efficiency of these coal-fired electric generating units (EGUs). In addition, increased reliance on natural gas and non-dispatchable energy sources has spurred efforts to further increase the reliability of coal EGUs. The Coal Powered EGU Efficiency and Reliability Dialogue brought together stakeholders from across the coal EGU industry to discuss methods for improvement. Participants at the event reviewed performance-enhancing innovations in coal EGUs, discussed the potential for data-driven management practices to increase efficiency and reliability, investigated the impacts of regulatory compliance on coal EGU performance, and discussed upcoming challenges for the coal industry. This report documents the key

  18. Intrinsic and extrinsic electrical and thermal transport of bulk black phosphorus

    Science.gov (United States)

    Hu, Sile; Xiang, Junsen; Lv, Meng; Zhang, Jiahao; Zhao, Hengcan; Li, Chunhong; Chen, Genfu; Wang, Wenhong; Sun, Peijie

    2018-01-01

    We report a comprehensive investigation of the electrical, thermal, and thermoelectric transport properties of bulk single-crystalline black phosphorus in wide temperature (2-300 K) and field (0-9 T) ranges. Electrical transport below T ≈ 250 K is found to be dominated by extrinsic hole-type charge carriers with large mobility exceeding 104 cm2/V s at low temperatures. While thermal transport measurements reveal an enhanced in-plane thermal conductivity maximum κ = 180 W/m K at T ≈ 25 K, it appears still to be largely constrained by extrinsic phonon scattering processes, e.g., the electron-phonon process, in addition to intrinsic umklapp scattering. The thermoelectric power and Nernst effect seem to be strongly influenced by ambipolar transport of charge carriers with opposite signs in at least the high-temperature region above 200 K, which diminishes the thermoelectric power factor of this material. Our results provide a timely update to the transport properties of bulk black phosphorus for future fundamental and applied research.

  19. Gas supply planning for new gas-fired electricity generation facilities

    International Nuclear Information System (INIS)

    Slocum, J.C.

    1990-01-01

    This paper explores several key issues in gas supply planning for new gas fired electric generation facilities. This paper will have two main sections, as follows: developing the gas supply plan for a gas-fired electricity generation facility and exploring key gas supply contract pricing issues

  20. Electricity generation: a case study in Turkey

    International Nuclear Information System (INIS)

    Kaygusuz, K.

    1999-01-01

    Large-scale electricity generation provides versatile energy of the highest quality. Today, fossil fuels such as coal, oil, and natural gas are the primary sources of this energy. However, these fossil energy sources are limited and using fossil energy sources has the undesirable effect of releasing emissions that burden the environment and alter the climate. Therefore, governments and companies all over the world should find new and renewable energy sources. On the other hand, over the past two decades, power station construction programs in the developing countries accounted for nearly 30% of total public investment. In a large number of these countries, shortages of electricity have become a critical constraint to economic growth. In Turkey, from 1980 to 1995, the amount for electricity generated increased about fourfold from 23,275 Gwh to 86,247 Gwh, and annual growth rates were in the double digits. This is a good development, but not enough for Turkey. (author)

  1. Electrically conductive, black thermal control coatings for spacecraft applications. III - Plasma-deposited ceramic matrix

    Science.gov (United States)

    Hribar, V. F.; Bauer, J. L.; O'Donnell, T. P.

    1987-01-01

    Five black, electrically-conductive thermal control coatings have been formulated and tested for application on the Galileo spacecraft. The coatings consist of both organic and inorganic systems applied on titanium, aluminum, and glass/epoxy composite surfaces. The coatings were tested under simulated space environment conditions. Coated specimens were subjected to thermal radiation, convective and combustive heating, and cryogenic conditions over a temperature range between -196 C and 538 C. Mechanical, physical, thermal, electrical, and thermooptical properties are presented for one of these coatings. This paper describes the preparation, characteristics, and spraying of iron titanate on titanium and aluminum, and presents performance results.

  2. Heat transfer efficient thermal energy storage for steam generation

    International Nuclear Information System (INIS)

    Adinberg, R.; Zvegilsky, D.; Epstein, M.

    2010-01-01

    A novel reflux heat transfer storage (RHTS) concept for producing high-temperature superheated steam in the temperature range 350-400 deg. C was developed and tested. The thermal storage medium is a metallic substance, Zinc-Tin alloy, which serves as the phase change material (PCM). A high-temperature heat transfer fluid (HTF) is added to the storage medium in order to enhance heat exchange within the storage system, which comprises PCM units and the associated heat exchangers serving for charging and discharging the storage. The applied heat transfer mechanism is based on the HTF reflux created by a combined evaporation-condensation process. It was shown that a PCM with a fraction of 70 wt.% Zn in the alloy (Zn70Sn30) is optimal to attain a storage temperature of 370 deg. C, provided the heat source such as solar-produced steam or solar-heated synthetic oil has a temperature of about 400 deg. C (typical for the parabolic troughs technology). This PCM melts gradually between temperatures 200 and 370 deg. C preserving the latent heat of fusion, mainly of the Zn-component, that later, at the stage of heat discharge, will be available for producing steam. The thermal storage concept was experimentally studied using a lab scale apparatus that enabled investigating of storage materials (the PCM-HTF system) simultaneously with carrying out thermal performance measurements and observing heat transfer effects occurring in the system. The tests produced satisfactory results in terms of thermal stability and compatibility of the utilized storage materials, alloy Zn70Sn30 and the eutectic mixture of biphenyl and diphenyl oxide, up to a working temperature of 400 deg. C. Optional schemes for integrating the developed thermal storage into a solar thermal electric plant are discussed and evaluated considering a pilot scale solar plant with thermal power output of 12 MW. The storage should enable uninterrupted operation of solar thermal electric systems during additional hours

  3. Understanding the thermal, mechanical and electrical properties of epoxy nanocomposites

    International Nuclear Information System (INIS)

    Sarathi, R.; Sahu, R.K.; Rajeshkumar, P.

    2007-01-01

    In the present work, the electrical, mechanical and thermal properties of epoxy nanocomposite materials were studied. The electrical insulation characteristics were analyzed through short time breakdown voltage test, accelerated electrical ageing test, and by tracking test. The breakdown voltage increases with increase in nano-clay content up to 5 wt%, under AC and DC voltages. The volume resistivity, permittivity and tan(δ) of the epoxy nanocomposites were measured. The Weibull studies indicate that addition of nanoclay upto 5 wt% enhances the characteristic life of epoxy nanocomposite insulation material. The tracking test results indicate that the tracking time is high with epoxy nanocomposites as compared to pure epoxy. Ageing studies were carried out to understand the surface characteristic variation through contact angle measurement. The hydrophobicity of the insulating material was analysed through contact angle measurement. The diffusion coefficients of the material with different percentage of clay in epoxy nanocomposites were calculated. The exfoliation characteristics in epoxy nanocomposites were analyzed through wide angle X-ray diffraction (WAXD) studies. The thermal behaviour of the epoxy nanocomposites was analyzed by carrying out thermo gravimetric-differential thermal analysis (TG-DTA) studies. Heat deflection temperature of the material was measured to understand the stability of the material for intermittent temperature variation. The dynamic mechanical analysis (DMA) results indicated that storage modulus of the material increases with small amount of clay in epoxy resin. The activation energy of the material was calculated from the DMA results

  4. Status and topics of thermal-hydraulic analysis for next-generation LWRs with passive safety systems

    International Nuclear Information System (INIS)

    Aritomi, Masanori; Ohnuki, Akira; Arai, Kenji; Kikuta, Michitaka; Yonomoto, Taisuke; Araya, Fumimasa; Akimoto, Hajime

    1999-01-01

    For increasing of electric power demand and reducing of carbon dioxide exhaust in the 21st century, studies of the next-generation light water reactor (LWR) with passive safety systems are developing in the world: AP-600 (by Westing House Co.); SBWR (by General Electric Co.); SWR1000 (by Siemens Co.); NP21 (by Mitsubishi Heavy Industry Co., et al.); JPSR (by JAERI). The passive equipment using natural circulation and natural convection are installed in the passive safety system, instead of active safety equipment, such as pumps, etc. It remains still as a important issue, however, to verify the reliability on the functions of the passive equipment, since that the driving forces of the passive equipment are small at comparison with the active safety equipment. The various subjects of thermal-hydraulic analysis for the next-generation light water reactors, such as temperature stratification in the passive safety systems, vapor condensation in the mixture of non-condensable gases and the interactions of the passive safety system with the primary cooling system, are illustrated and discussed in the paper. (M. Suetake)

  5. Microbial Fuel Cells using Mixed Cultures of Wastewater for Electricity Generation

    International Nuclear Information System (INIS)

    Zain, S.M; Roslani, N.S.; Hashim, R.; Anuar, N.; Suja, F.; Basi, N.E.A.; Anuar, N.; Daud, W.R.W.

    2011-01-01

    Fossil fuels (petroleum, natural gas and coal) are the main resources for generating electricity. However, they have been major contributors to environmental problems. One potential alternative to explore is the use of microbial fuel cells (MFCs), which generate electricity using microorganisms. MFCs uses catalytic reactions activated by microorganisms to convert energy preserved in the chemical bonds between organic molecules into electrical energy. MFC has the ability to generate electricity during the wastewater treatment process while simultaneously treating the pollutants. This study investigated the potential of using different types of mixed cultures (raw sewage, mixed liquor from the aeration tank and return waste activated sludge) from an activated sludge treatment plant in MFCs for electricity generation and pollutant removals (COD and total kjeldahl nitrogen, TKN). The MFC in this study was designed as a dual-chambered system, in which the chambers were separated by a Nafion TM membrane using a mixed culture of wastewater as a bio catalyst. The maximum power density generated using activated sludge was 9.053 mW/ cm 2 , with 26.8 % COD removal and 40 % TKN removal. It is demonstrated that MFC offers great potential to optimize power generation using mixed cultures of wastewater. (author)

  6. Studies of Electrical and Thermal Conductivities of Sheared Multi-Walled Carbon Nanotube with Isotactic Polypropylene Polymer Composites

    Directory of Open Access Journals (Sweden)

    Parvathalu Kalakonda

    2015-01-01

    at higher temperature due to isotropic electrical and thermal contact in both directions. Oriented MWCNT/iPP nanocomposites exhibit higher electrical and thermal conductivities, attributed primarily by orientation of nanotubes due to the shearing fabrication process.

  7. Experience in connecting the power generating units of thermal power plants to automatic secondary frequency regulation within the united power system of Russia

    International Nuclear Information System (INIS)

    Zhukov, A. V.; Komarov, A. N.; Safronov, A. N.; Barsukov, I. V.

    2009-01-01

    The principles of central control of the power generating units of thermal power plants by automatic secondary frequency and active power overcurrent regulation systems, and the algorithms for interactions between automatic power control systems for the power production units in thermal power plants and centralized systems for automatic frequency and power regulation, are discussed. The order of switching the power generating units of thermal power plants over to control by a centralized system for automatic frequency and power regulation and by the Central Coordinating System for automatic frequency and power regulation is presented. The results of full-scale system tests of the control of power generating units of the Kirishskaya, Stavropol, and Perm GRES (State Regional Electric Power Plants) by the Central Coordinating System for automatic frequency and power regulation at the United Power System of Russia on September 23-25, 2008, are reported.

  8. optimization methodologies of mixed electrical generators in algeria ...

    African Journals Online (AJOL)

    ABSTRACT. This article deals of the optimization of renewable energy electric generators, for the alimentation of radio telecommunication systems. The principals' interests of this system are the independence production, and the supplying of electric energy in isolated localities. Have at one's the energetic and economic ...

  9. Optimization of the Heat Exchangers of a Thermoelectric Generation System

    Science.gov (United States)

    Martínez, A.; Vián, J. G.; Astrain, D.; Rodríguez, A.; Berrio, I.

    2010-09-01

    The thermal resistances of the heat exchangers have a strong influence on the electric power produced by a thermoelectric generator. In this work, the heat exchangers of a thermoelectric generator have been optimized in order to maximize the electric power generated. This thermoelectric generator harnesses heat from the exhaust gas of a domestic gas boiler. Statistical design of experiments was used to assess the influence of five factors on both the electric power generated and the pressure drop in the chimney: height of the generator, number of modules per meter of generator height, length of the fins of the hot-side heat exchanger (HSHE), length of the gap between fins of the HSHE, and base thickness of the HSHE. The electric power has been calculated using a computational model, whereas Fluent computational fluid dynamics (CFD) has been used to obtain the thermal resistances of the heat exchangers and the pressure drop. Finally, the thermoelectric generator has been optimized, taking into account the restrictions on the pressure drop.

  10. Numerical simulation of the leaky dielectric microdroplet generation in electric fields

    Science.gov (United States)

    Kamali, Reza; Manshadi, Mohammad Karim Dehghan

    2016-07-01

    Microdroplet generation has a vast range of applications in the chemical, biomedical, and biological sciences. Several devices are applied to produce microdroplets, such as Co-flow, T-junction and Flow-focusing. The important point in the producing process is controlling the separated fluid volume in these devices. On the other hand, a large number of liquids, especially aqueous one, are influenced by electric or magnetic fields. As a consequence, an electric field could be used in order to affect the separated fluid volume. In this study, effects of an electric field on the microdroplet generation in a Co-flow device are investigated numerically. Furthermore, effects of some electrical properties such as permittivity on the separating process of microdroplets are studied. Leaky dielectric and perfect dielectric models are used in this investigation. According to the results, in the microdroplet generating process, leaky dielectric fluids show different behaviors, when an electric field is applied to the device. In other words, in a constant electric field strength, the volume of generated microdroplets can increase or decrease, in comparison with the condition without the electric field. However, for perfect dielectric fluids, droplet volume always decreases with increasing the electric field strength. In order to validate the numerical method of this study, deformation of a leaky dielectric droplet in an electric field is investigated. Results are compared with Taylor theoretical model.

  11. Evaluation of capital investment in thermoelectric generation projects in the Brazilian electric sector using the real options theory; Avaliacao de investimento de capital em projetos de geracao termoeletrica no setor eletrico brasileiro usando teoria das opcoes reais

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Alessandro de Lima

    2000-04-01

    In the Brazilian Electric System about 92% of the generated electricity is of hydraulic origin. Today the system is operating practically in the limit of your capacity. Solutions of short time to make possible the expansion of the offer of electricity generation go by the installation of cycle combining thermal using natural gas as fuel. In this dissertation, it was used the real options theory to evaluate generation assets in the Brazilian electricity sector. In Brazil, central operator dispatches a flexible thermal when the electricity spot price is larger than the operation costs. The operation decision is like an European call, where underlying asset is the electricity and the strike price is the operation cost. The value of the capacity is the sum of all decisions to operate the thermal unit, in the remaining life of unit. It was used Monte Carlo Simulation and Dynamic Programming to evaluate this model. The problem is divided in two parts. In the first part, the base case is fixed and evaluated and the expected NPV and project risk are calculated in function of contract level. In the second part, many sensibilities are done in relation to base case. At the end, the value of flexibility is calculated for each contract level. (author)

  12. Study of the electrical behavior of various magnetohydrodynamic generators using explosives

    International Nuclear Information System (INIS)

    Bernard, J.; Jouys, J.

    1969-01-01

    This report studies the electric behaviour of several types of pulse generators which use the M. H.D. conversion of explosives chemical energy to supply experiments of plasma physics. We study and compare their electric parameters and behaviour on ohmic and inductive loads. The electrical energy which appears on the load is studied in respect of the load and generator characteristics. We point out the way to amplify the initial electric energy. (author) [fr

  13. Economical evaluation of electricity generation considering externalities

    International Nuclear Information System (INIS)

    El-Kordy, M.N.; Badr, M.A.; Abed, K.A.; Ibrahim, Said M.A.

    2002-01-01

    The economics of renewable energy are the largest barrier to renewable penetration. Nevertheless, the strong desire to reduce environmental emissions is considered a great support for renewable energy sources. In this paper, a full analysis for the cost of the kWh of electricity generated from different systems actually used in Egypt is presented. Also renewable energy systems are proposed and their costs are analyzed. The analysis considers the external cost of emissions from different generating systems. A proposed large scale PV plant of 3.3 MW, and a wind farm 11.25 MW grid connected at different sites are investigated. A life cycle cost analysis for each system was performed using the present value criterion. The comparison results showed that wind energy generation has the lowest cost, followed by a combined cycle-natural gas fired system. A photovoltaic system still uses comparatively expensive technology for electricity generation; even when external costs are considered the capital cost of photovoltaic needs to be reduced by about 60% in order to be economically competitive. (Author)

  14. On the electricity shortage, price and electricity theft nexus

    International Nuclear Information System (INIS)

    Jamil, Faisal

    2013-01-01

    Pakistan is facing severe electricity shortfall of its history since 2006. Several measures have been implemented in order to mitigate electricity shortage. The focus has been on raising the installed capacity of electricity generation and transmission. The present policy results in expensive thermal electricity generation mostly using expensive and environmentally hazardous furnace oil and inability of utilities to recover their cost of supply although there is unprecedented rise in electricity tariffs. This study concentrates on the electricity demand and traces the relationship between electricity shortfalls, tariff rate and electricity theft in the background of recent electricity crisis using the data for the period 1985–2010. We employed the Granger causality test through error correction model and out-of-sample causality through variance decomposition method. Empirical evidence shows that electricity theft greatly influences electricity shortfalls through lowering investment and inefficient use of electricity. The study concludes that electricity crisis cannot be handled without combating rampant electricity theft in the country. - Highlights: ► The study investigates relationship among electricity outages, price and electricity theft. ► It employed Johansen approach, ECM and variance decomposition analysis. ► Empirical evidence shows that electricity theft causes outages and rising tariff rates. ► Variance decomposition analysis results are slightly different from ECM

  15. Projected costs of generating electricity - 2010 edition

    International Nuclear Information System (INIS)

    2010-01-01

    This joint report by the International Energy Agency (IEA) and the OECD Nuclear Energy Agency (NEA) is the seventh in a series of studies on electricity generating costs. It presents the latest data available for a wide variety of fuels and technologies, including coal and gas (with and without carbon capture), nuclear, hydro, onshore and offshore wind, biomass, solar, wave and tidal as well as combined heat and power (CHP). It provides levelised costs of electricity (LCOE) per MWh for almost 200 plants, based on data covering 21 countries (including four major non-OECD countries), and several industrial companies and organisations. For the first time, the report contains an extensive sensitivity analysis of the impact of variations in key parameters such as discount rates, fuel prices and carbon costs on LCOE. Additional issues affecting power generation choices are also examined. The study shows that the cost competitiveness of electricity generating technologies depends on a number of factors which may vary nationally and regionally. Readers will find full details and analyses, supported by over 130 figures and tables, in this report which is expected to constitute a valuable tool for decision makers and researchers concerned with energy policies and climate change

  16. Assessment of wind energy potential for electricity generation

    African Journals Online (AJOL)

    Wind energy is proposed as an alternative source of electricity to fossil fuel generators .... can be connected to the national grid line to supplement the shortfall that arises during the dry ... systems are environmentally friendly. By generating ...

  17. Essays on investment planning in electricity generating capacity

    Science.gov (United States)

    Gonzalez-Gomez, Jorge

    In the first part of this study we develop and analyze two mathematical models that incorporate a time changing demand for electricity and uncertainty of input prices. The first model highlights the shortcomings in assuming a constant plant utilization under uncertainty of input prices and the effects of such assumption on the optimal investment in electricity generating capacity in a simple two period model. The second model presents sufficient restrictions to the optimal investment in electricity generating capacity problem to allow for a recursive solution. The necessary restrictions are extremely limiting to the extend that we found a solution for very simple scenarios. In our opinion, the problem is better handled in a case by case basis rather than under a general dynamic framework. Following the spirit of our conclusions of the first part of our study, in the second part we provide a methodology to simulate long-term natural gas prices, we analyze the investment prospects of nuclear and natural gas generating capacity in Mexico and provide a constraint approach for the optimal generation of hydroelectric plants in the Mexican hydroelectric system. These three problems belong to the solution of the optimal investment in electricity generating capacity in Mexico. To simulate the uncertainty of natural gas prices, we assume that natural gas prices are the sum of two stochastic processes: short-term and long-term variability. We characterize the short-term variability of natural gas prices using an Exponential General Autoregressive Conditional Heteroskedastic (EGARCH) model. The uncertainty of the long-term variability of natural gas prices is based on the long-term natural gas prices scenarios of the National Energy Modeling System of the Energy Information Administration. Equipped with a methodology to simulate long-term natural gas prices, we investigate the investment prospects of nuclear and natural gas generating capacity in Mexico using the levelized

  18. Combined simulation of energy and thermal management for an electric vehicle

    Energy Technology Data Exchange (ETDEWEB)

    Mohrmann, Bjoern; Jeck, Peter [Institut fuer Kraftfahrzeuge Aachen (Germany); Simon, Carsten [fortiss GmbH, Muenchen (Germany); Ungermann, Jochen [Audi AG, Ingolstadt (Germany)

    2012-11-01

    The project eperformance, which is funded by the BMBF, is conducted by project partners from RWTH Aachen, Audi, Bosch Engineering and fortiss GmbH, in order to demonstrate the concept of an electric vehicle on the basis of a holistic development approach. To support this, several simulation platforms come into use, i.e. CFD Simulation for cooling concepts, electromagnetic simulations for electric machine design, physical simulation of cooling circuits as well as vehicle mechanics and controller design. To develop an energy efficient vehicle management, some of these simulation domains have to be combined, to simulate interdependencies between for example usage of high-voltage batteries, their thermal response and the impact for controller strategies. Within the project it was decided to use the Tool TISC (TLK Inter Software Connector) to combine as well a physical model, based on Modelica/Dymola to simulate thermal behaviours of components with a longitudinal vehicle model and a controller model, both based in MATLAB/Simulink. Advantages of such a coupled simulation are the re-usability of existing models in both tools with their tool-specific benefits as well as the possibility to cluster the models on different computers. The article will explain how the combined simulation is set up and parameterized, and will show two use cases: the thermal management of the two independent battery systems of the demonstrator vehicle and the torque distribution on the three electric machines in the vehicle, depending on the drive situation and the thermal state of the machines. (orig)

  19. Assessing energy efficiency of electric car bottom furnaces intended for thermal energization of minerals

    Science.gov (United States)

    Nizhegorodov, A. I.

    2017-01-01

    The paper deals with a new concept of electric furnaces for roasting and thermal energization of vermiculite and other minerals with vibrational transportation of a single-layer mass under constant thermal field. The paper presents performance calculation and comparative assessment of energy data for furnaces of different modifications: flame and electric furnaces with three units, furnaces with six units and ones with series-parallel connection of units, and furnaces of new concept.

  20. Electrical, thermal and abusive tests on lithium thionyl chloride cells

    Science.gov (United States)

    Frank, H. A.

    1980-04-01

    Electrical characterizations, thermal characterizations, and outer limits tests of lithium thionyl chloride cells are discussed. Graphs of energy density vs power density and heat rate vs time are presented along with results of forced reversal and high rate discharge tests.

  1. Power-Generation Characteristics After Vibration and Thermal Stresses of Thermoelectric Unicouples with CoSb3/Ti/Mo(Cu) Interfaces

    Science.gov (United States)

    Bae, Kwang Ho; Choi, Soon-Mok; Kim, Kyung-Hun; Choi, Hyoung-Seuk; Seo, Won-Seon; Kim, Il-Ho; Lee, Soonil; Hwang, Hae Jin

    2015-06-01

    Reliability tests for thermoelectric unicouples were carried out to investigate the adhesion properties of CoSb3/Ti/Mo(Cu) interfaces. The n-type In0.25 Co3.95Ni0.05Sb12 and p-type In0.25Co3FeSb12 bulks were prepared for fabricating a thermoelectric unicouple (one p- n couple) by an induction melting and a spark plasma sintering process. Mo-Cu alloy was selected as an electrode for the unicouples due to its high melting temperature and proper work function value. Many thermoelectric unicouples with the CoSb3/Ti/Mo(Cu) interfaces were fabricated with the proper brazing materials by means of a repeated firing process. Reliability of the unicouples with the interfaces was evaluated by a vibration test and a thermal cycling test. After the thermal cycling and vibration tests, the power-generation characteristics of the unicouples were compared with the unicouples before the tests. Even after the vibration test, electrical power with a power density of 0.5 W/cm2 was generated. The Ti-interlayer is considered as a possible candidate for making a reliable unicouple with high adhesion strength. With the thermal cycling test, the resistance of the unicouple increased and the electrical power from the unicouple decreased. A failure mode by the thermal cycling test was ascribed to a complex effect of micro-cracks originated from the thermal stress and oxidation problem of the thermoelectric materials; that is, a thick oxide layer more than 300 μm was detected after a high-temperature durability test of n-type In0.25Co3.95Ni0.05Sb12 material at 773 K in air for 7 days.

  2. Nuclear Power as an Option in Electrical Generation Planning for Small Economy and Electricity Grid

    International Nuclear Information System (INIS)

    Tomsic, Z.

    2012-01-01

    Implementing a NPP in countries with relatively small total GDP (small economy) and usually with small electricity grid face two major problems and constrains: the ability to obtain the considerable financial resources required on reasonable terms and to connect large NPP to small electricity grid. Nuclear generation financing in developing countries involves complex issues that need to be fully understood and dealt with by all the parties involved. The main topics covered by paper will be the: special circumstances related to the financing of NPP, costs and economic feasibility of NPP, conventional approaches for financing power generation projects in developing countries, alternative approaches for mobilizing financial resources. The safe and economic operation of a nuclear power plant (NPP) requires the plant to be connected to an electrical grid system that has adequate capacity for exporting the power from the NPP, and for providing a reliable electrical supply to the NPP for safe start-up, operation and normal or emergency shut-down of the plant. Connection of any large new power plant to the electrical grid system in a country may require significant modification and strengthening of the grid system, but for NPPs there may be added requirements to the structure of the grid system and the way it is controlled and maintained to ensure adequate reliability. Paper shows the comparative assesment of differrent base load technologies as an option in electrical generation planning for small economy and electricity grid.(author).

  3. Evaluation of electrical and thermal conductivity of polymeric wastes ...

    African Journals Online (AJOL)

    This work being gingered by the big menace being posed on our environment by polymeric waste and it's rechanneling involved the studying of the electrical and thermal conductivities of the polymers PP, PE, PS and nylon66 doped with charcoal and graphite. Five grams of each polymer was mixed with varying ...

  4. A hybrid method of incorporating extended priority list into equal incremental principle for energy-saving generation dispatch of thermal power systems

    International Nuclear Information System (INIS)

    Cheng, Chuntian; Li, Shushan; Li, Gang

    2014-01-01

    The energy-saving generation dispatch (ESGD) policy released by Chinese Government in 2007 is a new code for optimally dispatching electric power generation portfolio in the country with the dual objectives of improving energy efficiency and reducing environmental pollution. The ESGD is substantially different from the competitive market in the developed economies, the traditional economic dispatching or the rational dispatching principle implemented in China prior to the new policy. This paper develops a hybrid method that integrates the extended priority list (EPL), the equal incremental principle (EIP) and a heuristic method to optimize daily generation schedules under ESGD. The EPL is presented to search desirable units set that satisfies the complicated duration period requirements based on thermal unit generation priority list. The EIP is developed to allocate load among the committed units within the combined set. A heuristic method is proposed to deal with inequality constraints, which usually result in difficulty for power allocation, and used to improve these results. The algorithm has been embedded into a newly developed decision support system that is currently being used by operators of the Guizhou Province Power Grid to make day-ahead quarter-hourly generation schedules. - Highlights: • Electric power industry is one of key and important fields for energy conservation and emission reduction in China. • The energy-saving generation dispatch policy was released by Chinese government in 2007. • A Hybrid algorithm for energy-saving generation dispatch scheduling of thermal power system is presented. • The algorithm has been embedded into a newly developed decision support system

  5. Generating Electricity from Water through Carbon Nanomaterials.

    Science.gov (United States)

    Xu, Yifan; Chen, Peining; Peng, Huisheng

    2018-01-09

    Over the past ten years, electricity generation from water in carbon-based materials has aroused increasing interest. Water-induced mechanical-to-electrical conversion has been discovered in carbon nanomaterials, including carbon nanotubes and graphene, through the interaction with flowing water as well as moisture. In this Concept article, we focus on the basic principles of electric energy harvesting from flowing water through carbon nanomaterials, and summarize the material modification and structural design of these nanogenerators. The current challenges and potential applications of power conversion with carbon nanomaterials are finally highlighted. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Experiment Investigation on Electrical and Thermal Performances of a Semitransparent Photovoltaic/Thermal System with Water Cooling

    Directory of Open Access Journals (Sweden)

    Guiqiang Li

    2014-01-01

    Full Text Available Different from the semitransparent building integrated photovoltaic/thermal (BIPV/T system with air cooling, the semitransparent BIPV/T system with water cooling is rare, especially based on the silicon solar cells. In this paper, a semitransparent photovoltaic/thermal system (SPV/T with water cooling was set up, which not only would provide the electrical power and hot water, but also could attain the natural illumination for the building. The PV efficiency, thermal efficiency, and exergy analysis were all adopted to illustrate the performance of SPV/T system. The results showed that the PV efficiency and the thermal efficiency were about 11.5% and 39.5%, respectively, on the typical sunny day. Furthermore, the PV and thermal efficiencies fit curves were made to demonstrate the SPV/T performance more comprehensively. The performance analysis indicated that the SPV/T system has a good application prospect for building.

  7. New Electro-Thermal Battery Pack Model of an Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Muhammed Alhanouti

    2016-07-01

    Full Text Available Since the evolution of the electric and hybrid vehicle, the analysis of batteries’ characteristics and influence on driving range has become essential. This fact advocates the necessity of accurate simulation modeling for batteries. Different models for the Li-ion battery cell are reviewed in this paper and a group of the highly dynamic models is selected for comparison. A new open circuit voltage (OCV model is proposed. The new model can simulate the OCV curves of lithium iron magnesium phosphate (LiFeMgPO4 battery type at different temperatures. It also considers both charging and discharging cases. The most remarkable features from different models, in addition to the proposed OCV model, are integrated in a single hybrid electrical model. A lumped thermal model is implemented to simulate the temperature development in the battery cell. The synthesized electro-thermal battery cell model is extended to model a battery pack of an actual electric vehicle. Experimental tests on the battery, as well as drive tests on the vehicle are performed. The proposed model demonstrates a higher modeling accuracy, for the battery pack voltage, than the constituent models under extreme maneuver drive tests.

  8. Thermal stability and electrical conductivity in polyethers-molybdenum disulfide nanocomposites

    International Nuclear Information System (INIS)

    Mirabal, N.; Aguirre, P.; Santa Ana, M.A.; Benavente, E.; Gonzalez, Guillermo

    2003-01-01

    The intercalation of poly(ethylene oxide) (PEO), into molybdenum disulfide, like that of other electron pair donors, leads to mixed ionic-electronic conductors. At room temperature, intercalates show electrical and lithium-ion conductivities better than MoS 2 and bulk PEO composites, respectively. However, these products are known to be sensitive to temperature; indeed, in the range 80-100 deg. C an irreversible decrease of the electrical conductivity is observed. In order to investigate these features, the thermal behavior of a series of polyethers of different molecular weights (poly(ethylene glycol) (Mw 3400) and PEO with Mw in the range 10 4 -4x10 6 , pure and intercalated in MoS 2 , (Li x (MoS 2 )(polyether) y with x∼0.1 and y=1.1-1.5), was comparatively analyzed. Furthermore, the effect of thermal treatment of the sample on the electrical conductivity was studied for one of the intercalated products. Results indicate that irreversible changes, detected by both loss of weight and a significant conductivity lowering, are occurring in the range from about 100 deg. C to a temperature near to the decomposition point of the organic phase at about 350 deg. C

  9. A Bayesian stochastic frontier analysis of Chinese fossil-fuel electricity generation companies

    International Nuclear Information System (INIS)

    Chen, Zhongfei; Barros, Carlos Pestana; Borges, Maria Rosa

    2015-01-01

    This paper analyses the technical efficiency of Chinese fossil-fuel electricity generation companies from 1999 to 2011, using a Bayesian stochastic frontier model. The results reveal that efficiency varies among the fossil-fuel electricity generation companies that were analysed. We also focus on the factors of size, location, government ownership and mixed sources of electricity generation for the fossil-fuel electricity generation companies, and also examine their effects on the efficiency of these companies. Policy implications are derived. - Highlights: • We analyze the efficiency of 27 quoted Chinese fossil-fuel electricity generation companies during 1999–2011. • We adopt a Bayesian stochastic frontier model taking into consideration the identified heterogeneity. • With reform background in Chinese energy industry, we propose four hypotheses and check their influence on efficiency. • Big size, coastal location, government control and hydro energy sources all have increased costs

  10. The Estimation of Externalities Resulting from the Electricity Generation

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Jong Tae; Ha, Jae Joo

    2003-03-15

    The methodology, program, and the representative results for the estimation of externalities was reviewed. The review of them are based on the ExternE Project which is a representative research project for the estimation of externalities resulting from the various energy generating systems. The results for the study will be used as basic data for the comparative study on the integrated risk estimation for various energy generating systems including nuclear power plants. Also, these results will be used as comparative data in the establishment of a integrated comparative risk assessment tool and in the comparative study of the impacts resulting from the various electricity generating systems. These studies make it possible to compare the environmental impacts of nuclear power generation and other electricity generation systems. Therefore, this will of use in the enhancement of public acceptance of nuclear power generation.

  11. The Estimation of Externalities Resulting from the Electricity Generation

    International Nuclear Information System (INIS)

    Jeong, Jong Tae; Ha, Jae Joo

    2003-03-01

    The methodology, program, and the representative results for the estimation of externalities was reviewed. The review of them are based on the ExternE Project which is a representative research project for the estimation of externalities resulting from the various energy generating systems. The results for the study will be used as basic data for the comparative study on the integrated risk estimation for various energy generating systems including nuclear power plants. Also, these results will be used as comparative data in the establishment of a integrated comparative risk assessment tool and in the comparative study of the impacts resulting from the various electricity generating systems. These studies make it possible to compare the environmental impacts of nuclear power generation and other electricity generation systems. Therefore, this will of use in the enhancement of public acceptance of nuclear power generation

  12. Developing A Family-Size Biogas-Fueled Electricity Generating System

    Directory of Open Access Journals (Sweden)

    Agus Haryanto

    2017-06-01

     Keywords: biogas; family size; generator; electricity; bio-filter.  Article History: Received Janury 16th 2017; Received in revised form 2nd June 2017; Accepted 18th June 2017; Available online How to Cite This Article: Haryanto, A., Marotin, F., Triyono, S., Hasanudin, U. (2017, Developing A Family-Size Biogas-Fueled Electricity Generating System. International Journal of Renewable Energy Develeopment, 6(2, 111-118. https://doi.org/10.14710/ijred.6.2.111-118

  13. Piezoelectric components wirelessly driven by dipole antenna-like electric field generator

    Energy Technology Data Exchange (ETDEWEB)

    Bhuyan, S., E-mail: elesatya@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore); Kumar, R.; Panda, S.K. [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore); Hu, J. [Lab of Precision Drive, Nanjing University of Aeronautics and Astronautics, Nanjing 210026 (China)

    2011-08-25

    Highlights: > Wireless energy transmission technique. > Dipole antenna-like electric field generator. > Piezoelecctric resonance. > Finite element analyses. > Simulations and experimental verifications. - Abstract: A new technique of transmitting electric energy wirelessly to piezoelectric components by using a dipole antenna-like electric field generator is explored. Two square size brass plate-shaped live and ground electrodes are used to form a dipole antenna-like electric field generator. When the dipole antenna-like electric field generator in electric resonance with an inductor, a maximum output power of 2.72 mW and an energy conversion efficiency of 0.0174% have been achieved wirelessly by the piezoelectric plate area of 40 mm{sup 2} operating in the thickness vibration mode, placed at the center 4 mm away from the antenna plane with an optimum electrical load of 1365 {Omega}, resonant frequency of 782 kHz, 1 cm electrodes separation, 2500 cm{sup 2} electrode area of dipole antenna-like structure, and input ac source power of 15.58 W applied to the series of dipole antenna-like structure and inductor. The theoretically calculated results have been validated by the experimental studies. It is seen that at the resonance frequency and optimum electrical load, the output power of the wirelessly driven piezoelectric component decreases with the size of piezoelectric component, distance of piezoelectric component from the electrode of antenna plane, but increases with the antenna electrode area.

  14. Biomechanical energy harvesting: generating electricity during walking with minimal user effort.

    Science.gov (United States)

    Donelan, J M; Li, Q; Naing, V; Hoffer, J A; Weber, D J; Kuo, A D

    2008-02-08

    We have developed a biomechanical energy harvester that generates electricity during human walking with little extra effort. Unlike conventional human-powered generators that use positive muscle work, our technology assists muscles in performing negative work, analogous to regenerative braking in hybrid cars, where energy normally dissipated during braking drives a generator instead. The energy harvester mounts at the knee and selectively engages power generation at the end of the swing phase, thus assisting deceleration of the joint. Test subjects walking with one device on each leg produced an average of 5 watts of electricity, which is about 10 times that of shoe-mounted devices. The cost of harvesting-the additional metabolic power required to produce 1 watt of electricity-is less than one-eighth of that for conventional human power generation. Producing substantial electricity with little extra effort makes this method well-suited for charging powered prosthetic limbs and other portable medical devices.

  15. Renewable Generators' Consortium: ensuring a market for green electricity

    International Nuclear Information System (INIS)

    1999-03-01

    This project summary focuses on the objectives and key achievements of the Renewable Generators Consortium (RGC) which was established to help renewable energy projects under the Non-Fossil Fuel Obligation (NFFO) to continue to generate in the open liberated post-1998 electricity market. The background to the NFFO is traced, and the development of the Consortium, and the attitudes of generators and suppliers to the Consortium are discussed along with the advantages of collective negotiations through the RGC, the Heads of Terms negotiations, and the success of RGC which has demonstrated the demand for green electricity

  16. The Contribution of Electricity Generation to Greenhouse Effect

    International Nuclear Information System (INIS)

    Lubis, Erwansyah

    2008-01-01

    The development activities has successfully increasing the human kind, but also has increasing trend the planet changes radically, because of the greenhouse effect (GHE), decreasing ozone layer and acid rain, that all could treat the living of the species-species and including man inside. The electricity generation and transportation are the main contribution of greenhouse gas (GHG), reaching 1/3 of global emission. Base on the Kyoto protocol in 1997, that all countries, alone or together agree to reduce the emission of GG of 5.2 % under the emission of the 1990. The decreasing of GHG could be reached by implementing the technology generation that contain low carbon, such a natural gas, hydro power, wind, solar and nuclear power. Diversification of electricity generation has to take into a count of environmental capacity, so the supply stability and sustainable development could be reached. The IAEA results studies indicated that the emission factor of fossil fuel 2 times greater compare to the natural gas. The emission factor of wind and biomass lie between solar and nuclear power. In the electricity generation chain, nuclear power emit the 25 g of CO 2 /kWh compare to fossil fuel emit 250 - 1250 g CO 2 /kWh. (author)

  17. Examination of spent fuel radiation energy conversion for electricity generation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Haneol; Yim, Man-Sung, E-mail: msyim@kaist.ac.kr

    2016-04-15

    Highlights: • Utilizing conversion of radiation energy of spent fuel to electric energy. • MCNPX modeling and experiment were used to estimate energy conversion. • The converted energy may be useful for nuclear security applications. • The converted energy may be utilized for safety applications through energy storage. - Abstract: Supply of electricity inside nuclear power plant is one of the most important considerations for nuclear safety and security. In this study, generation of electric energy by converting radiation energy of spent nuclear fuel was investigated. Computational modeling work by using MCNPX 2.7.0 code along with experiment was performed to estimate the amount of electric energy generation. The calculation using the developed modeling work was validated through comparison with an integrated experiment. The amount of electric energy generation based on a conceptual design of an energy conversion module was estimated to be low. But the amount may be useful for nuclear security applications. An alternative way of utilizing the produced electric energy could be considered for nuclear safety application through energy storage. Further studies are needed to improve the efficiency of the proposed energy conversion concept and to examine the issue of radiation damage and economic feasibility.

  18. Westinghouse AP1000 Electrical Generation Costs - Meeting Marketplace Requirements

    International Nuclear Information System (INIS)

    Paulson, C. Keith

    2002-01-01

    The re-emergence of nuclear power as a leading contender for new base-load electrical generation is not an occurrence of happenstance. The nuclear industry, in general, and Westinghouse, specifically, have worked diligently with the U.S. power companies and other nuclear industry participants around the world to develop future plant designs and project implementation models that address prior problem areas that led to reduced support for nuclear power. In no particular order, the issues that Westinghouse, as an engineering and equipment supply company, focused on were: safety, plant capital costs, construction schedule reductions, plant availability, and electric generation costs. An examination of the above criteria quickly led to the conclusion that as long as safety is not compromised, simplifying plant designs can lead to positive progress of the desired endpoints for the next and later generations of nuclear units. The distinction between next and later generations relates to the readiness of the plant design for construction implementation. In setting requirement priorities, one axiom is inviolate: There is no exception, nor will there be, to the Golden Rule of business. In the electric power generation industry, once safety goals are met, low generation cost is the requirement that rules, without exception. The emphasis in this paper on distinguishing between next and later generation reactors is based on the recognition that many designs have been purposed for future application, but few have been able to attain the design pedigree required to successfully meet the requirements for next generation nuclear units. One fact is evident: Another generation of noncompetitive nuclear plants will cripple the potential for nuclear to take its place as a major contributor to new electrical generation. Only two plant designs effectively meet the economic tests and demonstrate both unparalleled safety and design credibility due to extensive progress toward engineering

  19. CO2 emissions of nuclear electricity generation

    International Nuclear Information System (INIS)

    Wissel, Steffen; Mayer-Spohn, Oliver; Fahl, Ulrich; Blesl, Markus; Voss, Alfred

    2008-01-01

    A survey of LCA studies on nuclear electricity generation revealed life cycle CO 2 emissions ranging between 3 g/kWhe to 60 g/kWhe and above. Firstly, this paper points out the discrepancies in studies by estimating the CO 2 emissions of nuclear power generation. Secondly, the paper sets out to provide critical review of future developments of the fuel cycle for light water reactors and illustrates the impact of uncertainties on the specific CO 2 emissions of nuclear electricity generation. Each step in the fuel cycle will be considered and with regard to the CO 2 emissions analysed. Thereby different assumptions and uncertainty levels are determined for the nuclear fuel cycle. With the impacts of low uranium ore grades for mining and milling as well as higher burn-up rates future fuel characteristics are considered. Sensitivity analyses are performed for all fuel processing steps, for different technical specifications of light water reactors as well as for further external frame conditions. (authors)

  20. Private wind powered electricity generators for industry in the UK

    Science.gov (United States)

    Thabit, S. S.; Stark, J.

    This paper investigates the impact of the provisions of the new Energy Act, 1983 on industrial wind-powered private generators of electricity and the effects of published tariffs on various industrial working patterns. Up to 30 percent savings can be achieved in annual electricity bill costs for an industrial generator/user of electricity working a single daily shift, if located in a favorable, 7 m/s mean annual wind speed regime. Variation of the availability charge between Electricity Boards about a base value of 0.70 pounds sterling/kVA was found to have insignificant (+ or - 1.3 percent) impact on total electricity bill costs. It was also shown that for industrial users of electricity, the simpler two-rate purchase terms were commercially adequate when compared with the four-rate alternative where expensive metering becomes necessary.

  1. Determining appropriate feed-in tariff rates to promote biomass-to-electricity generation in Eastern Ontario, Canada

    International Nuclear Information System (INIS)

    Moore, Steven; Durant, Vincent; Mabee, Warren E.

    2013-01-01

    On-site data collection, interviews, and financial models were used to determine the feed-in tariff (FIT) rate required to encourage investment in the generation of electricity from currently unused biomass from the Eastern Ontario forest industry. A financial model was adapted and run to determine the net present value, internal rate of return, and payback period associated with a 15 MW biomass-to-electricity facility. The analysis suggests that Ontario should consider a stronger incentive than the recently-offered CDN$ 0.13 kW −1 h −1 for biomass-to-electricity. If no customer for heat generated from the plant can be found, FIT rates between CDN$ 0.17–0.22 kW −1 h −1 are necessary to achieve a 15% internal rate of return and a simple payback of approximately 5 yr; achieving a price of CDN$ 0.013 kW −1 of thermal output still requires elevated FIT rates between CDN$ 0.15–0.21 kW −1 h −1 to meet economic performance criteria. Other barriers, particularly regulations regarding the use of operating engineers in steam plants, should also be addressed to facilitate development of biomass-to-electricity. Without these changes, it is likely that biomass will be significantly under-used and will not contribute to the renewable energy goals of Ontario. - Highlights: • Economic performance of biomass-to-electricity generation in Ontario is assessed. • Feed-in tariffs needed to meet industrial payback and IRR targets are determined. • Existing feed-in tariff rates for biomass must be raised to meet industrial targets. • Incentives that adjust feedstock price might be explored to increase biomass use

  2. Ice thermal storage air conditioning system for electric load leveling; Denryoku heijunka to hyochikunetsu system

    Energy Technology Data Exchange (ETDEWEB)

    Shigenaga, Y. [Daikin Industries Ltd., Osaka (Japan)

    1998-08-15

    Thermal storage air conditioning system is the one to use energy stored into thermal storing materials by using night electric power and to operate effective air conditioning. Therefore, as load can be treated by the stored energy, volume of the apparatus can be reduced. And, by reduction of the consumed power at day time, it can contribute to leveling of electric power demand. In general, there are two types in the thermal storage method: one is a method to store as thermal energy, and the other is that to store as chemical energy. For conditions required for the storing materials, important elements on their actual uses are not only physical properties such as large thermal storage per unit and easy thermal in- and out-puts, but also safety, long-term reliability, and easy receiving and economics containing future. The ice thermal storage air conditioning system is classified at the viewpoint of type of ice, kind of thermal storing medium, melting method on using cooling and heating, kinds of thermal medium on cooling and heating. 3 refs., 5 figs., 2 tabs.

  3. Reliability payments to generation capacity in electricity markets

    International Nuclear Information System (INIS)

    Olsina, Fernando; Pringles, Rolando; Larisson, Carlos; Garcés, Francisco

    2014-01-01

    Electric power is a critical input to modern economies. Generation adequacy and security of supply in power systems running under competition are currently topics of high concern for consumers, regulators and governments. In a market setting, generation investments and adequacy can only be achieved by an appropriate regulatory framework that sets efficient remuneration to power capacity. Theoretically, energy-only electricity markets are efficient and no additional mechanism is needed. Nonetheless, the energy-only market design suffers from serious drawbacks. Therefore, jointly with the evolution of electricity markets, many remunerating mechanisms for generation capacity have been proposed. Explicit capacity payment was the first remunerating approach implemented and perhaps still the most applied. However, this price-based regulation has been applied no without severe difficulties and criticism. In this paper, a new reliability payment mechanism is envisioned. Capacity of each generating unit is paid according to its effective contribution to overall system reliability. The proposed scheme has many attractive features and preserves the theoretical efficiency properties of energy-only markets. Fairness, incentive compatibility, market power mitigation and settlement rules are investigated in this work. The article also examines the requirements for system data and models in order to implement the proposed capacity mechanism. A numerical example on a real hydrothermal system serves for illustrating the practicability of the proposed approach and the resulting reliability payments to the generation units. - Highlights: • A new approach for remunerating supply reliability provided by generation units is proposed. • The contribution of each generating unit to lessen power shortfalls is determined by simulations. • Efficiency, fairness and incentive compatibility of the proposed reliability payment are assessed

  4. Optimal electricity generation system expansion and nuclear power option in Belarus

    International Nuclear Information System (INIS)

    Yakushau, A.; Mikhalevich, A.

    2000-01-01

    After having declared independence, the Republic of Belarus was forced to import 90% of fuel consumed and 25% of electricity. The deficit of peak electric capacity reached 40%. The imported fuel covers the last years because the drop in the production reduced the energy consumption in the Republic but not the needs of the energy sector. Annual payments for imported fuel and electricity are equal to the sum of an annual state budget of Belarus (about 1.5 billion USD) and current debts were not lower 300 million. Comparative analysis of the different scenarios of the electricity generation system expansion showed that an optimum way for electricity generation is installation of the combine cycle units and construction nuclear power plants. The results of the study also showed that the option based on replacement of deficit of the electricity generation by the way of the construction combine cycle units with capacities 450 MW turned out to be the best solution among non nuclear options. (author)

  5. Outlook for gas sales for electricity generation in the Northeast

    International Nuclear Information System (INIS)

    Linderman, C.W.

    1998-01-01

    Issues regarding future supply and demand of natural gas as opposed to coal in the electric power generation sector, generation performance standards of coal plants, new combined cycle applications, distributed generation, and the advantages of natural gas over coal are discussed. The electricity demand and supply situation in the Northeast, present and future, and the growing movement toward green power, green power certification programs, the need and demand for disclosure of emissions and fuel source of supply, price and other customer information were summarized. Nuclear power generation and the chances of it being replaced by natural gas-fuelled generation are assessed. Some pipeline siting issues and the need for careful coordination with the electric system to minimize new corridors, are also reviewed. The advantages of natural gas in terms of technology and reduced pollution, hence cleaner air, were cited as the reasons why natural gas has almost unlimited potential as the fuel of choice well into the 21. century

  6. Small-scale electric generators for arctic applications

    International Nuclear Information System (INIS)

    Lamp, T.R.

    1995-01-01

    Forest fires that have endangered remote US Air Force sites equipped with radioisotope thermoelectric generators (RTGs) has prompted the assessment of power generating systems as substitutes for RTGs in small scale (10--120 watt) applications. A team of scientists and engineers of the US Air Forces' Wright Laboratory conductd an assessment of electrical power technologies for use by the Air Force in remote, harsh environments. The surprisingly high logistics costs of operating fossil fuel generators resulted in the extension of the assessment to non-RTG sites. The candidate power sources must operate unattended for long periods at a high level of operational reliability. Selection of the optimum power generation technology is complicated and heavily driven by the severe operating environment and compounded by the remoteness of the location. It is these site-related characteristics, more than any other, that drive the selection of a safe and economical power source for Arctic applications. A number of proven power generation technologies were evaluated. The assessment concluded that RGTs are clearly the safest, most reliable, and most economical approach to supplying electrical power for remote, difficult to assess locations. The assessment also indicated that the logistics costs associated with combustion driven generator systems could be substantially reduced through the use of conversion technologies which have been previously developed for space power applications. copyright 1995 American Institute of Physics

  7. Impact of a 1,000-foot thermal mixing zone on the steam electric power industry

    International Nuclear Information System (INIS)

    Veil, J.A.

    1994-04-01

    Thermal discharge requirements for power plants using once-through cooling systems are based on state water quality standards for temperatures that must be met outside of designated mixing zones. This study evaluates the impact of limiting the extent of thermal mixing zones. This study evaluates the impact of limiting the extent of thermal mixing zones to no more than 1,000 feet from the discharge point. Data were collected from 79 steam electric plants. Of the plants currently using once-through cooling systems, 74% could not meet current thermal standards at the edge of a 1,000-foot mixing zone. Of this total, 68% would retrofit cooling towers, and 6% would retrofit diffusers. The estimated nationwide capital cost for retrofitting plants that could not meet current thermal standards at the edge of a 1,000-foot mixing zone is $21.4 billion. Conversion of a plant from once-through cooling to cooling towers or addition of diffusers would result in a lower energy output from that plant. For the affected plants, the total estimated replacement cost would be $370 to $590 million per year. Some power companies would have to construct new generating capacity to meet the increased energy demand. The estimated nationwide cost of this additional capacity would be $1.2 to $4.8 billion. In addition to the direct costs associated with compliance with a 1,000-foot mixing zone limit, other secondary environmental impacts would also occur. Generation of the additional power needed would increase carbon dioxide emissions by an estimated 8.3 million tons per year. In addition, conversion from once-through cooling systems to cooling towers at affected plants would result in increased evaporation of about 2.7 million gallons of water per minute nationwide

  8. Investigation of Electricity Generation by Using Gamma Radiation from Spent Fuels

    International Nuclear Information System (INIS)

    Lee, Haneol; Yim, Man-Sung Yim

    2015-01-01

    The purpose of this study is to investigate the electric power generation with scale spent fuel. OrigenArp has analyzed gamma radiation environment of spent fuel assembly, MCNPX has analyzed the scintillator behavior, and experimental work has analyzed the electric output of photovoltaic cell. Gamma radiation environment analysis result indicates gamma source rapidly decreases for the early storage period. Scintillator analysis result calculates the photon flux distribution which enters photovoltaic cell. Photovoltaic cell experiment calculates electric current, voltage current generation per each system unit. Generated electric power can be used to cope with existing safety system (i.e. storage monitoring system) under severe accident or to operate security system under external invasion situation (i.e. passive physical barrier system). Several researchers have shown that converting radiation energy into electric energy is possible. Karl Scharf studied the direct electric conversion of radiation energy by using photovoltaic cells. Researchers in University of Massachusetts Lowell have studied radiation-electric energy conversion by using gadolinium oxide scintillator and dye sensitized solar cell (DSSCs) and N. Horuichi et al. studied radiation-electric energy conversion by using inorganic scintillators and amorphous and crystal photovoltaic cells

  9. Resolution 147/012. It authorize the Central Libertador / SA aeolian generation company to generate an aeolian electricity source by an electric power generating plant located in Maldonado town 4 AA Catastral section, and the Sistema inerconectado Nacional connection

    International Nuclear Information System (INIS)

    2012-01-01

    This decree authorizes the generation of electricity using aeolian energy as the primary electricity source. This project was presented by the 'Libertador / S.A' aeolian generation company with the proposal to install an electrical plant in Maldonado town. This authorization is according to the Electric Wholesale Market regulation

  10. Climate Change Impacts on Rivers and Implications for Electricity Generation in the United States

    Science.gov (United States)

    Miara, A.; Vorosmarty, C. J.; Macknick, J.; Corsi, F.; Cohen, S. M.; Tidwell, V. C.; Newmark, R. L.; Prousevitch, A.

    2015-12-01

    The contemporary power sector in the United States is heavily reliant on water resources to provide cooling water for thermoelectric generation. Efficient thermoelectric plant operations require large volumes of water at sufficiently cool temperatures for their cooling process. The total amount of water that is withdrawn or consumed for cooling and any potential declines in efficiencies are determined by the sector's fuel mix and cooling technologies. As such, the impact of climate change, and the extent of impact, on the power sector is shaped by the choice of electricity generation technologies that will be built over the coming decades. In this study, we model potential changes in river discharge and temperature in the contiguous US under a set of climate scenarios to year 2050 using the Water Balance Model-Thermoelectric Power and Thermal Pollution Model (WBM-TP2M). Together, these models quantify, in high-resolution (3-min), river temperatures, discharge and power plant efficiency losses associated with changes in available cooling water that incorporates climate, hydrology, river network dynamics and multi-plant impacts, on both single power plant and regional scales. Results are used to assess the aptness and vulnerability of contemporary and alternative electricity generation pathways to changes in climate and water availability for cooling purposes, and the concomitant impacts on power plant operating efficiencies. We assess the potential impacts by comparing six regions (Northeast, Southeast, Midwest, Great Plains, Southwest, Northwest as in the National Climate Assessment (2014)) across the US. These experiments allow us to assess tradeoffs among electricity-water-climate to provide useful insight for decision-makers managing regional power production and aquatic environments.

  11. Nigeria electricity crisis: Power generation capacity expansion and environmental ramifications

    International Nuclear Information System (INIS)

    Aliyu, Abubakar Sadiq; Ramli, Ahmad Termizi; Saleh, Muneer Aziz

    2013-01-01

    Access to clean and stable electricity is essential in actualizing Nigeria's quest for joining the league of twenty most industrious nations by the year 2020 (vision 20:2020). No country can develop and sustain it development without having a minimum access to electricity for it larger percentage of its population. At present, Nigeria depends petroleum reserves and its aged hydro plant instalments for electricity generation to feed the 40% of its total population that are connected to the national grid. This paper summarizes literature on the current energy issues in Nigeria and introduces the difficulty of the issues involved. The paper also analyses the current (2010) electricity generation as well as the future expansion plans of the Government in 20 years period. The plan includes the introduction of new electrify generation technologies that have not been in used in the base year (2010). The electricity generation system of (including the future expansion plan) was simulated using the LEAP System (Long-range Energy Alternative and Planning). We also investigated the potential environmental impact of siting a nuclear power plant in one of the potential sites based on the site's specific micro-meteorology (land use) and meteorology using the US EPA (Environmental Protection Agency) models; AERMOD 12345. - Highlights: • This paper scrutinizes literature on Nigeria's energy crisis and presents the policies of the clean technology as solutions. • Only 40% of Nigeria's population is connected to the grid; and this population faces power problems 60% of the time. • Simulation of Nigeria electricity generation system was done. • Air dispersion modellingmodelling for radiological health risk from NPP was done

  12. Electrical resistivity and thermal properties of compatibilized multi-walled carbon nanotube/polypropylene composites

    Directory of Open Access Journals (Sweden)

    A. Szentes

    2012-06-01

    Full Text Available The electrical resistivity and thermal properties of multi-walled carbon nanotube/polypropylene (MWCNT/PP composites have been investigated in the presence of coupling agents applied for improving the compatibility between the nanotubes and the polymer. A novel olefin-maleic-anhydride copolymer and an olefin-maleic-anhydride copolymer based derivative have been used as compatibilizers to achieve better dispersion of MWCNTs in the polymer matrix. The composites have been produced by extrusion followed by injection moulding. They contained different amounts of MWCNTs (0.5, 2, 3 and 5 wt% and coupling agent to enhance the interactions between the carbon nanotubes and the polymer. The electrical resistivity of the composites has been investigated by impedance spectroscopy, whereas their thermal properties have been determined using a thermal analyzer operating on the basis of the periodic thermal perturbation method. Rheological properties, BET-area and adsorption-desorption isotherms have been determined. Dispersion of MWCNTs in the polymer has been studied by scanning electron microscopy (SEM.

  13. Dynamic thermal characteristics of heat pipe via segmented thermal resistance model for electric vehicle battery cooling

    Science.gov (United States)

    Liu, Feifei; Lan, Fengchong; Chen, Jiqing

    2016-07-01

    Heat pipe cooling for battery thermal management systems (BTMSs) in electric vehicles (EVs) is growing due to its advantages of high cooling efficiency, compact structure and flexible geometry. Considering the transient conduction, phase change and uncertain thermal conditions in a heat pipe, it is challenging to obtain the dynamic thermal characteristics accurately in such complex heat and mass transfer process. In this paper, a ;segmented; thermal resistance model of a heat pipe is proposed based on thermal circuit method. The equivalent conductivities of different segments, viz. the evaporator and condenser of pipe, are used to determine their own thermal parameters and conditions integrated into the thermal model of battery for a complete three-dimensional (3D) computational fluid dynamics (CFD) simulation. The proposed ;segmented; model shows more precise than the ;non-segmented; model by the comparison of simulated and experimental temperature distribution and variation of an ultra-thin micro heat pipe (UMHP) battery pack, and has less calculation error to obtain dynamic thermal behavior for exact thermal design, management and control of heat pipe BTMSs. Using the ;segmented; model, the cooling effect of the UMHP pack with different natural/forced convection and arrangements is predicted, and the results correspond well to the tests.

  14. Electricity and generator availability in LMIC hospitals: improving access to safe surgery.

    Science.gov (United States)

    Chawla, Sagar; Kurani, Shaheen; Wren, Sherry M; Stewart, Barclay; Burnham, Gilbert; Kushner, Adam; McIntyre, Thomas

    2018-03-01

    Access to reliable energy has been identified as a global priority and codified within United Nations Sustainable Goal 7 and the Electrify Africa Act of 2015. Reliable hospital access to electricity is necessary to provide safe surgical care. The current state of electrical availability in hospitals in low- and middle-income countries (LMICs) throughout the world is not well known. This study aimed to review the surgical capacity literature and document the availability of electricity and generators. Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search for surgical capacity assessments in LMICs in MEDLINE, PubMed, and World Health Organization Global Health Library was performed. Data regarding electricity and generator availability were extracted. Estimated percentages for individual countries were calculated. Of 76 articles identified, 21 reported electricity availability, totaling 528 hospitals. Continuous electricity availability at hospitals providing surgical care was 312/528 (59.1%). Generator availability was 309/427 (72.4%). Estimated continuous electricity availability ranged from 0% (Sierra Leone and Malawi) to 100% (Iran); estimated generator availability was 14% (Somalia) to 97.6% (Iran). Less than two-thirds of hospitals providing surgical care in 21 LMICs have a continuous electricity source or have an available generator. Efforts are needed to improve electricity infrastructure at hospitals to assure safe surgical care. Future research should look at the effect of energy availability on surgical care and patient outcomes and novel methods of powering surgical equipment. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Study of light-absorbing crystal birefringence and electrical modulation mechanisms for coupled thermal-optical effects.

    Science.gov (United States)

    Zhou, Ji; He, Zhihong; Ma, Yu; Dong, Shikui

    2014-09-20

    This paper discusses Gaussian laser transmission in double-refraction crystal whose incident light wavelength is within its absorption wave band. Two scenarios for coupled radiation and heat conduction are considered: one is provided with an applied external electric field, the other is not. A circular heat source with a Gaussian energy distribution is introduced to present the crystal's light-absorption process. The electromagnetic field frequency domain analysis equation and energy equation are solved to simulate the phenomenon by using the finite element method. It focuses on the influence of different values such as wavelength, incident light intensity, heat transfer coefficient, ambient temperature, crystal thickness, and applied electric field strength. The results show that the refraction index of polarized light increases with the increase of crystal temperature. It decreases as the strength of the applied electric field increases if it is positive. The mechanism of electrical modulation for the thermo-optical effect is used to keep the polarized light's index of refraction constant in our simulation. The quantitative relation between thermal boundary condition and strength of applied electric field during electrical modulation is determined. Numerical results indicate a possible approach to removing adverse thermal effects such as depolarization and wavefront distortion, which are caused by thermal deposition during linear laser absorption.

  16. The path to clean energy: direct coupling of nuclear and renewable technologies for thermal and electrical applications

    Energy Technology Data Exchange (ETDEWEB)

    Bragg-Sitton, Shannon [Idaho National Lab. (INL), Idaho Falls, ID (United States). Nuclear Fuel Performance and Design; Boardman, Richard [Idaho National Lab. (INL), Idaho Falls, ID (United States). Advanced Process and Decision Systems; Ruth, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States). Strategic Energy Analysis Center

    2015-07-01

    The U.S. Department of Energy (DOE) recognizes the need to transform the energy infrastructure of the U.S. and elsewhere to systems that can significantly reduce environmental impacts in an efficient and economically viable manner while utilizing both clean energy generation sources and hydrocarbon resources. Thus, DOE is supporting research and development that could lead to more efficient utilization of clean nuclear and renewable energy generation sources. A concept being advanced by the DOE Offices of Nuclear Energy (NE) and Energy Efficiency and Renewable Energy (EERE) is tighter coupling of nuclear and renewable energy sources in a manner that better optimizes energy use for the combined electricity, industrial manufacturing, and the transportation sectors. This integration concept has been referred to as a “hybrid system” that is capable of providing energy (thermal or electrical) where it is needed, when it is needed. For the purposes of this work, the hybrid system would integrate two or more energy resources to generate two or more products, one of which must be an energy commodity, such as electricity or transportation fuel. This definition requires coupling of subsystems ‘‘behind’’ the electrical transmission bus, where energy flows are dynamically apportioned as necessary to meet demand and the system has a single connection to the grid that provides dispatchable electricity as required while capital intensive generation assets operate at full capacity. Development of integrated energy systems for an “energy park” must carefully consider the intended location and the associated regional resources, traditional industrial processes, energy delivery infrastructure, and markets to identify viable region-specific system configurations. This paper will provide an overview of the current status of regional hybrid energy system design, development and application of dynamic analysis tools to assess technical and economic performance, and

  17. Joining and Performance of Alkali Metal Thermal-to-electric Converter (AMTEC)

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Min-Soo; Lee, Wook-Hyun; Woo, Sang-Kuk [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2017-07-15

    The alkali-Metal Thermal-to-electric Converter (AMTEC) is one of the promising static energy conversion technologies for the direct conversion of thermal energy to electrical energy. The advantages over a conventional energy converter are its high theoretical conversion efficiency of 40% and power density of 500 W/kg. The working principle of an AMTEC battery is the electrochemical reaction of the sodium through an ion conducting electrolyte. Sodium ion pass through the hot side of the beta”-alumina solid electrolyte (BASE) primarily as a result of the pressure difference. This pressure difference across the BASE has a significant effect on the overall performance of the AMTEC system. In order to build the high pressure difference across the BASE, hermeticity is required for each joined components for high temperature range of 900°C. The AMTEC battery was manufactured by utilizing robust joining technology of BASE/insulator/metal flange interfaces of the system for both structural and electrical stability. The electrical potential difference between the anode and cathode sides, where the electrons emitted from sodium ionization and recombined into sodium, was characterized as the open-circuit voltage. The efforts of technological improvement were concentrated on a high-power output and conversion efficiency. This paper discusses about the joining and performance of the AMTEC systems.

  18. Thermal and Electrical Characterization of the Carbon Nanofibers Based Cement Composites

    Directory of Open Access Journals (Sweden)

    Agnieszka ŚLOSARCZYK

    2017-08-01

    Full Text Available The paper describes the influence of chemical modification of vapor grown carbon nanofibers (VGCnFs on the thermal and electrical properties of the cement composites. The surface modification of nanofibers was performed by means of ozone and nitric acid treatments. It was shown that the oxidized carbon nanofibers surface plays an important role in shaping the mechanical and especially electrical properties of cement composite. For cement matrix modified with carbon nanofibers subjected to oxidized treatment, the slightly increase of cement paste resistivity was observed. It confirms the better adhesion of carbon nanofibers to cement paste. However, independently of carbon nanofibers modification, the occurrence of VGCnFs in cement paste increased the electrical conductivity of the composite in comparison to the cement paste without fibers. The obtained values of electrical resistivity were comparable with values of cement composites modified with 4 mm long carbon fibers. Moreover, it was shown that the chemical modification of carbon nanofibers surface does not influence on the thermal properties of cement composites. In case of cement paste with unmodified and modified carbon nanofibers, the Seebeck voltage was proportional to the temperature difference and was independent of the oxidation degree of carbon nanofibers.DOI: http://dx.doi.org/10.5755/j01.ms.23.2.14993

  19. Development and bottlenecks of renewable electricity generation in China: a critical review.

    Science.gov (United States)

    Hu, Yuanan; Cheng, Hefa

    2013-04-02

    This review provides an overview on the development and status of electricity generation from renewable energy sources, namely hydropower, wind power, solar power, biomass energy, and geothermal energy, and discusses the technology, policy, and finance bottlenecks limiting growth of the renewable energy industry in China. Renewable energy, dominated by hydropower, currently accounts for more than 25% of the total electricity generation capacity. China is the world's largest generator of both hydropower and wind power, and also the largest manufacturer and exporter of photovoltaic cells. Electricity production from solar and biomass energy is at the early stages of development in China, while geothermal power generation has received little attention recently. The spatial mismatch in renewable energy supply and electricity demand requires construction of long-distance transmission networks, while the intermittence of renewable energy poses significant technical problems for feeding the generated electricity into the power grid. Besides greater investment in research and technology development, effective policies and financial measures should also be developed and improved to better support the healthy and sustained growth of renewable electricity generation. Meanwhile, attention should be paid to the potential impacts on the local environment from renewable energy development, despite the wider benefits for climate change.

  20. Concepts of investment risks and strategies in electricity generation

    International Nuclear Information System (INIS)

    De Joode, J.; Boots, M.G.

    2005-06-01

    This report deals with the specific investment risks in electricity generation and discusses the problems associated with energy investments in general and focus on the additional or changing risks resulting from electricity market liberalisation. The focus is on (1) risks under the control of the electricity company, and on (2) market risks, such as the risk of price changes. Ultimately, some of the approaches and strategies that enable electricity producers to counter or mitigate these risks are discussed

  1. Electrical properties and thermal expansion of strontium aluminates

    Energy Technology Data Exchange (ETDEWEB)

    Zakharchuk, K.V. [Department of Materials and Ceramic Engineering, CICECO, University of Aveiro, 3810-193 Aveiro (Portugal); Yaremchenko, A.A., E-mail: ayaremchenko@ua.pt [Department of Materials and Ceramic Engineering, CICECO, University of Aveiro, 3810-193 Aveiro (Portugal); Fagg, D.P. [TEMA-NRD, Mechanical Engineering Department, University of Aveiro, 3810-193 Aveiro (Portugal)

    2014-11-15

    Highlights: • Sr{sub 3}Al{sub 2}O{sub 6}, SrAl{sub 2}O{sub 4} and Sr{sub 4}Al{sub 14}O{sub 25} ceramics are semiconductors. • Electrical conductivity is as low as 10{sup −6}−4×10{sup −5} S/cm at 1273 K in dry air. • SrAl{sub 2}O{sub 4} is a mixed conductor with predominant ionic conductivity. • Sr{sub 3}Al{sub 2}O{sub 6} shows significant contribution of protonic transport in wet atmospheres. • Average TECs vary in the range (8.5–11.1)×10{sup −6} K{sup −1} and are p(O{sub 2})-independent. - Abstract: Strontium aluminate ceramics, including Sr{sub 3}Al{sub 2}O{sub 6}, SrAl{sub 2}O{sub 4} and Sr{sub 4}Al{sub 14}O{sub 25}, synthesized by glycine–nitrate combustion and sintered at 1773 K in air, were characterized by thermal analysis, dilatometry and electrical measurements in controlled atmospheres. All studied strontium aluminates are semiconductors with electrical conductivities as low as 10{sup −6}−4×10{sup −5} S/cm at 1273 K in dry air. Electrical measurements in controlled atmospheres in combination with ion transference number determination demonstrated that SrAl{sub 2}O{sub 4} is a mixed conductor with predominant ionic conductivity and increasing n-type and p-type electronic contributions under highly reducing and oxidizing conditions, respectively. While the behavior of electrical conductivity of Sr{sub 3}Al{sub 2}O{sub 6} in dry atmospheres was qualitatively similar to that of SrAl{sub 2}O{sub 4}, a significant increase of conductivity in wet atmospheres was attributed to a protonic contribution to electrical conduction, in correlation with thermogravimetric data and the tendency of this material to form a hydrogarnet at low temperatures. The average thermal expansion coefficients of strontium aluminates, (8.5–11.1)×10{sup −6} K{sup −1} at 333–1373 K, increase with increasing strontium content in the sequence Sr{sub 4}Al{sub 14}O{sub 25} < SrAl{sub 2}O{sub 4} < Sr{sub 3}Al{sub 2}O{sub 6} and are essentially

  2. Future trends in electrical energy generation economics in the United States

    Science.gov (United States)

    Schmitt, R. W.; Fox, G. R.; Shah, R. P.; Stewart, P. J.; Vermilyea, D. A.

    1977-01-01

    Developments related to the economics of coal-fired systems in the U.S. are mainly considered. The historical background of the U.S. electric generation industry is examined and the U.S. electrical generation characteristics in the year 1975 are considered. It is pointed out that coal-fired power plants are presently the largest source of electrical energy generation in the U.S. Questions concerning the availability and quality of coal are investigated. Currently there are plans for converting some 50 large oil and gas-fired generating plants to coal, and it is expected that coal will be the fuel used in almost all fossil-fired base load additions to generating capacity. Aspects of advanced energy conversion from coal are discussed, taking into account the performance and economic potential of the energy conversion systems.

  3. Generation and Use of Thermal Energy in the Industrial Sector and Opportunities to Reduce its Carbon Emissions

    International Nuclear Information System (INIS)

    McMillan, Colin; Boardman, Richard; McKellar, Michael; Sabharwall, Piyush; Ruth, Mark; Bragg-Sitton, Shannon

    2016-01-01

    Changes are occurring throughout the U.S. economy, especially in regard to how energy is generated and used in the electricity, buildings, industrial, and transportation sectors. These changes are being driven by environmental and energy security concerns and by economics. The electric-sector market share of natural gas and variable renewable generation, such as wind and solar photovoltaics (PV), continues to grow. The buildings sector is evolving to meet efficiency standards, the transportation sector is evolving to meet efficiency and renewable fuels standards, and the industrial sector is evolving to reduce emissions. Those changes are driving investment and utilization strategies for generation and other assets. Nuclear and renewable energy sources are important to consider in the energy sector’s evolution because both are considered to be clean and non-carbon-emitting energy sources. The Idaho National Laboratory (INL) and the National Renewable Energy Laboratory (NREL) are jointly investigating potential synergies between technologies exploiting nuclear and renewable energy sources. The two laboratories have held several joint workshops since 2011. Those workshops brought together experts in both areas to identify synergies and potential opportunities to work together. Workshop participants identified nuclear-renewable hybrid energy systems (N-R HESs) as one of the opportunities and recommended investigating whether N-R HESs could both generate dispatchable electricity without carbon emissions and provide clean energy to industrial processes. They also recommended analyzing the potential for N-R HESs to provide dispatchable capacity to a grid with high penetrations of non-dispatchable resources and to investigate whether real inertia provided by thermal power cycles within N-R HESs provides value to the grid. This report is one of a series of reports INL and NREL are producing to investigate the technical and economic aspects of N-R HESs. Previous reports

  4. Generation and Use of Thermal Energy in the Industrial Sector and Opportunities to Reduce its Carbon Emissions

    Energy Technology Data Exchange (ETDEWEB)

    McMillan, Colin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Boardman, Richard [Idaho National Lab. (INL), Idaho Falls, ID (United States); McKellar, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sabharwall, Piyush [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ruth, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bragg-Sitton, Shannon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Changes are occurring throughout the U.S. economy, especially in regard to how energy is generated and used in the electricity, buildings, industrial, and transportation sectors. These changes are being driven by environmental and energy security concerns and by economics. The electric-sector market share of natural gas and variable renewable generation, such as wind and solar photovoltaics (PV), continues to grow. The buildings sector is evolving to meet efficiency standards, the transportation sector is evolving to meet efficiency and renewable fuels standards, and the industrial sector is evolving to reduce emissions. Those changes are driving investment and utilization strategies for generation and other assets. Nuclear and renewable energy sources are important to consider in the energy sector’s evolution because both are considered to be clean and non-carbon-emitting energy sources. The Idaho National Laboratory (INL) and the National Renewable Energy Laboratory (NREL) are jointly investigating potential synergies between technologies exploiting nuclear and renewable energy sources. The two laboratories have held several joint workshops since 2011. Those workshops brought together experts in both areas to identify synergies and potential opportunities to work together. Workshop participants identified nuclear-renewable hybrid energy systems (N-R HESs) as one of the opportunities and recommended investigating whether N-R HESs could both generate dispatchable electricity without carbon emissions and provide clean energy to industrial processes. They also recommended analyzing the potential for N-R HESs to provide dispatchable capacity to a grid with high penetrations of non-dispatchable resources and to investigate whether real inertia provided by thermal power cycles within N-R HESs provides value to the grid. This report is one of a series of reports INL and NREL are producing to investigate the technical and economic aspects of N-R HESs. Previous reports

  5. Comparative ranking of 0. 1-10 MW/sub e/ solar thermal electric power systems. Volume II. Supporting data. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, J.P.; Brown, K.C.; Finegold, J.G.; Gresham, J.B.; Herlevich, F.A.; Kriz, T.A.

    1980-07-01

    This report is part of a two-volume set summarizing the results of a comparative ranking of generic solar thermal concepts designed specifically for electric power generation. The original objective of the study was to project the mid-1990 cost and performance of selected generic solar thermal electric power systems for utility applications and to rank these systems by criteria that reflect their future commercial acceptance. This study considered plants with rated capacities of 1-10 MW/sub e/, operating over a range of capacity factors from the no-storage case to 0.7 and above. Later, the study was extended to include systems with capacities from 0.1 to 1 MW/sub e/, a range that is attractive to industrial and other nonutility applications. Volume I summarizes the results for the full range of capacities from 0.1 to 1.0 MW/sub e/. Volume II presents data on the performance and cost and ranking methodology.

  6. Optimization Methodologies of Mixed Electrical Generators in ...

    African Journals Online (AJOL)

    This article deals of the optimization of renewable energy electric generators, for the alimentation of radio telecommunication systems. ... Have at one's the energetic and economic models, and simulation tools, we effected an optimization ...

  7. Dispersed generation: impact on the electricity system

    International Nuclear Information System (INIS)

    Delfanti, M.; Merlo, M.; Silvestri, A.

    2009-01-01

    The paper deals with the impact of Dispersed Generation (D G) on the national electricity system, by proposing a practical approach for determining the current capacity of the networks to accepts this form of generation (hosting capacity). With the prospect of an increasing intake of D G, we finally draft a possible evolution of distribution networks based on the integration of energy and information networks. [it

  8. Thermal management of batteries

    Science.gov (United States)

    Gibbard, H. F.; Chen, C.-C.

    Control of the internal temperature during high rate discharge or charge can be a major design problem for large, high energy density battery systems. A systematic approach to the thermal management of such systems is described for different load profiles based on: thermodynamic calculations of internal heat generation; calorimetric measurements of heat flux; analytical and finite difference calculations of the internal temperature distribution; appropriate system designs for heat removal and temperature control. Examples are presented of thermal studies on large lead-acid batteries for electrical utility load levelling and nickel-zinc and lithium-iron sulphide batteries for electric vehicle propulsion.

  9. Trends in Japan's power generation costs after the Fukushima Daiichi Nuclear Power Plant accident and their influence on finance of electric utilities

    International Nuclear Information System (INIS)

    Matsuo, Yuhji; Yamaguchi, Yuhji; Murakami, Tomoko

    2013-01-01

    Following the Fukushima Daiichi nuclear power plant accident, the nuclear reactors that were suspended for periodic inspections after the Fukushima accident were not permitted to resume operation, and nuclear power generation in Japan continued to decline. In this article, the authors quantitatively evaluated the effects on power generation costs of Japan's situation, using electric utilities financial reports up to FY 2011. We also analyzed the profitability of the Japanese electric industry, using the financial statements included in the reports, and quantitatively evaluated the effects of changes in power generation costs. The total cost of power generation has increased from 7.5 trillion yen in FY 2010 before the Fukushima accident to 9.6 trillion yen in FY 2011 and to 10.6 trillion yen in FY 2012. In particular, the fuel cost for thermal power generation rose sharply from 3.7 trillion yen in FY 2010 to 6.1 trillion yen in FY 2011 and 7.3 trillion yen in FY 2012, almost doubling in the two years from FY 2010 to 2012. The unit cost of power generation rose sharply from 8.6 yen/kWh in FY 2010 to 11.8 yen/kWh in FY 2011 and 13.5 yen/kWh in FY 2012. The unit cost is expected to rise even further in FY 2013 due to the weak yen. As the result not only Tokyo Electric Power Company, but also the other general electric utilities registered huge net losses. Their retained earnings (total of eight utilities) dropped by 2 trillion yen between FY 2010 and 2012. With increased thermal power generation, the risk of rising costs associated with changes in primary energy prices and exchange rates has increased drastically. For the stability of the electricity industry and the development of the Japanese economy, the government should clearly formulate a basic policy regarding the composition of power sources, and an effective plan both at home and abroad, and should develop a system that will be also to handle sudden changes in the composition of power sources. (author)

  10. Effects of further integration of distributed generation on the electricity market

    NARCIS (Netherlands)

    Frunt, J.; Kling, W.L.; Myrzik, J.M.A.; Nobel, Frank; Klaar, D.A.M.

    2006-01-01

    Environmental concern leads to legislation to stimulate the further integration of renewable energy in the Dutch electricity supply system. Distributed generation is suited for the integration of renewable energy sources. Furthermore it can be used to generate both heat and electricity in a more

  11. Thermal and Electrical Investigation of Conductive Polylactic Acid Based Filaments

    Science.gov (United States)

    Dobre, R. A.; Marcu, A. E.; Drumea, A.; Vlădescu, M.

    2018-06-01

    Printed electronics gain momentum as the involved technologies become affordable. The ability to shape electrostatic dissipative materials in almost any form is useful. The idea to use a general-purpose 3D printer to manufacture the electrical interconnections for a circuit is very attractive. The advantage of using a 3D printed structure over other technologies are mainly the lower price, less requirements concerning storage and use conditions, and the capability to build thicker traces while maintaining flexibility. The main element allowing this to happen is a printing filament with conductive properties. The paper shows the experiments that were performed to determine the thermal and electrical properties of polylactic acid (PLA) based ESD dissipative filament. Quantitative results regarding the thermal behavior of the DC resistance and the variation of the equivalent parallel impedance model parameters (losses resistance, capacitance, impedance magnitude and phase angle) with frequency are shown.. Using these results, new applications like printed temperature sensors can be imagined.

  12. Thermal design of an electric motor using Particle Swarm Optimization

    International Nuclear Information System (INIS)

    Jandaud, P-O; Harmand, S; Fakes, M

    2012-01-01

    In this paper, flow inside an electric machine called starter-alternator is studied parametrically with CFD in order to be used by a thermal lumped model coupled to an optimization algorithm using Particle Swarm Optimization (PSO). In a first case, the geometrical parameters are symmetric allowing us to model only one side of the machine. The optimized thermal results are not conclusive. In a second case, all the parameters are independent. In this case, the flow is strongly influenced by the dissymmetry. Optimization results are this time a clear improvement compared to the original machine.

  13. Technical descriptions of Hudson River electricity generating stations

    International Nuclear Information System (INIS)

    Hutchison, J.B.

    1988-01-01

    Six fossil-fueled and one nuclear electricity generating plants are sited along the Hudson River estuary between kilometers 8 and 228, measured from the river mouth. Their aggregate rated capacity is 5,798 MW of electricity; operating at that capacity they would withdraw cooling water from the river at the rate of 1.5 x 10 to the 9th power cu m/d and reject heat at the rate of 155 x 10 to the 9th power kcal/d. Three of these plants, the fossil-fueled Roseton and Bowline and the nuclear Indian Point facilities; account for 75% of total rated capacity, 62% of maximum water withdrawal, and 79% of potential heat rejection. These three plants and a proposed pumped-storage facility at Cornwall, all sited between km 60 and 106, were the focus of environmental litigation. The Indian Point plant normally operates at 100% generation capacity; the other plants may experience daily operating load changes that vary from approximately 50% to 100% of total generation capacity, depending on system electrical demand or economic considerations. All plants experience periodic unscheduled outages for repairs. 6 refs., 7 figs

  14. Volumetric solar thermal receiver principles and technological approach

    International Nuclear Information System (INIS)

    Sagie, D.; Gruntman, S.; Taragan, E.; Danino, M.; Weiss, S.; Mimon, Y.

    1996-01-01

    Solar energy has received much interest in recent years, being a clean free of pollution or other environmental dotage), and inexhaustible energy source. It is also considered safer than some other non conventional energy sources (like nuclear energy). The interest in solar energy is motivated mainly by the growing awareness of the environmental problems associated with the use of . conventional keels. However, solar energy may become a serious alternative only if it can be used efficiently in major energy consuming industries (like the chemical industry), or be used for electricity generation. Those facilities are nowadays solely depend on fossil fuels as the prime source of energy . The solar energy, reaches file Earth as radiation, can be utilized either by direct quantum conversion using photo-voltaic solar cells, or by converting the radiation into thermal energy, to be used directly for heating, or to feed a thermal to electric converting cycle. Alter three decades of huge spending on the development of photo-voltaic systems those devices are commercially competitive only on very small energy scale, while solar thermal commercial applications are evident. The prominent examples are the domestic heating water receivers (direct thermal), and LUZ International electricity generation plants which are currently operated on a commercial basis, supplying 80 MWe per plant. Direct thermal exploitation of solar energy is naturally more efficient than converting to electricity but is limited to specific applications and locations especially since thermal storage at high temperature is not commercially viable. Efficient electricity production at competitive price is clearly the biggest opportunity for solar energy. (authors)

  15. Experimental investigation of the thermal and electrical performance of the heat pipe BIPV/T system with metal wires

    International Nuclear Information System (INIS)

    Wang, Zhangyuan; Qiu, Feng; Yang, Wansheng; Zhao, Xudong; Mei, Sheng

    2016-01-01

    Highlights: • Proposing a novel heat pipe BIPV/T system. • Conducting experiments to investigate the performance of the system. • Establishing the relation between the system performance and operating parameters. - Abstract: Heat pipe building integrated photovoltaic/thermal system (heat pipe BIPV/T system) can produce both the electrical and thermal energies at the same time, which have been paid enormous attentions since the energy crisis in the 1970s. In this paper, the heat pipe BIPV/T system with the metal wires filling into the space between the finned heat pipes and insulation has been proposed, which will be expected to enhance the heat transfer and improve the electrical generation of the system. To investigate the thermal performance of the system, the variations of the temperatures, e.g., flat-plate glass cover, PV panel, filling space, heat pipe, and tank water, as well as the ambient temperature, were measured, and the system’s thermal efficiency was calculated and studied for different simulated solar radiations and water flow rates. It was found that the temperatures of the flat-plate glass cover, PV panels, filling space, and heat pipe presented the similar variation pattern when the ambient temperature was stable. The tank water temperature could reach the maximum of 53.83 °C when the simulated solar radiation was at 900 W/m"2 and the water flow rate was at 200 l/h. The linear relation between the system efficiency and (T_m_e_a_n − T_a_m_b)/I had been setup. The maximum thermal efficiency was found at 44.04% with the simulated solar radiation of 300 W/m"2 and water flow rate of 200 l/h, and 7.9% for the maximum electrical efficiency. Compared with the traditional systems of the previous research, the proposed system performed well with additional features, e.g., low cost, waste materials recycling. This research will be helpful in indicating the potential research area of the low-carbon-emission and energy-saving technology for the

  16. Electricity Generation Characteristics of Energy-Harvesting System with Piezoelectric Element Using Mechanical-Acoustic Coupling

    Directory of Open Access Journals (Sweden)

    Hirotarou Tsuchiya

    2016-01-01

    Full Text Available This paper describes the electricity generation characteristics of a new energy-harvesting system with piezoelectric elements. The proposed system is composed of a rigid cylinder and thin plates at both ends. The piezoelectric elements are installed at the centers of both plates, and one side of each plate is subjected to a harmonic point force. In this system, vibration energy is converted into electrical energy via electromechanical coupling between the plate vibration and piezoelectric effect. In addition, the plate vibration excited by the point force induces a self-sustained vibration at the other plate via mechanical-acoustic coupling between the plate vibrations and an internal sound field into the cylindrical enclosure. Therefore, the electricity generation characteristics should be considered as an electromechanical-acoustic coupling problem. The characteristics are estimated theoretically and experimentally from the electric power in the electricity generation, the mechanical power supplied to the plate, and the electricity generation efficiency that is derived from the ratio of both power. In particular, the electricity generation efficiency is one of the most appropriate factors to evaluate a performance of electricity generation systems. Thus, the effect of mechanical-acoustic coupling is principally evaluated by examining the electricity generation efficiency.

  17. How much have electricity shortages hampered China's GDP growth?

    International Nuclear Information System (INIS)

    Cheng, Y.S.; Wong, W.K.; Woo, C.K.

    2013-01-01

    Based on an econometric analysis of the annual growth data for China's GDP and electricity generation from 1953 to 2010, we find that electricity generation growth Granger causes GDP growth, but not vice versa. We also find that the GDP elasticity of electricity generation is about 0.6, implying that a 1% increase in China's electricity generation growth would increase GDP growth by 0.6%. While Deng's reform raised China's GDP growth rate by about 5% per year, it did not alter the GDP elasticity of electricity generation. Hence, an obvious strategy to promote China's economic growth would be accelerating electricity generation expansion. Rapidly adding thermal generation units, however, could have large-scale, adverse environmental impacts. We therefore support China's 2011 five-year plan, which calls for expanding investments in renewable energy, conservation and energy efficiency as well as improving China's integrated electricity planning and cost-based pricing decisions. - Highlights: ► China's electricity generation growth is found to Granger cause GDP growth, but not vice versa. ► The estimate of the GDP elasticity of electricity generation is about 0.6. ► A 1% increase in China's electricity generation growth would increase GDP growth by 0.6%

  18. Bimodal Nuclear Thermal Rocket Analysis Developments

    Science.gov (United States)

    Belair, Michael; Lavelle, Thomas; Saimento, Charles; Juhasz, Albert; Stewart, Mark

    2014-01-01

    Nuclear thermal propulsion has long been considered an enabling technology for human missions to Mars and beyond. One concept of operations for these missions utilizes the nuclear reactor to generate electrical power during coast phases, known as bimodal operation. This presentation focuses on the systems modeling and analysis efforts for a NERVA derived concept. The NERVA bimodal operation derives the thermal energy from the core tie tube elements. Recent analysis has shown potential temperature distributions in the tie tube elements that may limit the thermodynamic efficiency of the closed Brayton cycle used to generate electricity with the current design. The results of this analysis are discussed as well as the potential implications to a bimodal NERVA type reactor.

  19. Design of very high speed electric generators

    International Nuclear Information System (INIS)

    Labollita, Santiago

    2008-01-01

    This work approaches the design process of an electric generator suitable for running efficiently at high speed, driven by a turbo shaft.The axial flux concept was used.For the mechanical design of the prototype, cooling capacity and mounting method were considered, looking for simplicity of the parts evolved. Neodymium-iron-boron permanent magnets were used as magnetic source.For the electrical design, a calculation tool was developed in order to predict the prototype electrical parameters and optimize its geometry.The goal was to obtain 1 kW of electric power at a speed of 100,000 rpm.The efficiency and electrical behaviour of the prototype were characterized at speeds between 2,000 rpm and 30,000 rpm and then the behaviour at the design condition was predicted by obtaining an equivalent electric circuit.The estimated load voltage was 237 V as well as an electrical efficiency of 95%.Eddy current effects were not recognized. Increase of the internal resistance and decree of inductance were observed while raising the electric frequency.Finally, an electronic system was developed in order to use the prototype as a c.c. motor. Global performance was measured according to different supply characteristic. An optimum supply voltage was found.A maximum efficiency of 63% was reached. [es

  20. Getting data for prediction of electricity generation from photovoltaic power plants

    International Nuclear Information System (INIS)

    Majer, V.; Hejtmankova, P.

    2012-01-01

    This paper deals with the short term prediction of generated electricity from photovoltaic power plants. This way of electricity generation is strongly dependent on the actual weather, mainly solar radiation and temperature. In this paper the simple method for getting solar radiation data is presented. (Authors)