New Brunswick Power Corporation: Business plan, 1994-1999

International Nuclear Information System (INIS)

1994-02-01

The first publicly available business plan for the New Brunswick Power Corp. is presented. The five-year plan provides an overview of the Corporation's performance and directions, including possible future rate increases. A review of the corporate history of the utility is followed by a description of the strategic framework under which the Corporation conducts its business operations. The information presented includes customer requirements, power generation and transmission, system operations, personnel management, environmental protection, and external factors affecting operations. This overview demonstrates the complex issues facing the utility, the choices made in the past, and the matters that will have to be faced in the future. The business overview is followed by focused business plans in six key functional areas (facilities, operations, personnel, technology, environment, and finances) and comprehensive financial forecasts that outline a commitment to maintain competitive rates for customers. The reasoning behind the forecasts is explained and a glossary is included. 21 figs., 16 tabs

Powers and Duties of Corporate Affairs Commission

African Journals Online (AJOL)

Mofasony

POWERS AND DUTIES OF THE CORPORATE AFFAIRS. COMMISSION ... The Registrar-General is the Chief Executive of the Commission and is saddled .... Federal Board of Inland Revenue Department of the Ministry of Finance v). Register ...

An electron beam flue gas treatment plant for a coal fired thermal power station. EBA demonstration plant in Chengdu thermal power station (China EBA Project)

International Nuclear Information System (INIS)

Doi, Yoshitaka; Nakanishi, Ikuo; Shi, Jingke

1999-01-01

Ebara's electron beam flue gas treatment plant was installed and is being demonstrated in Chengdu Thermal Power Station, Sichuan, China. The demonstration is proving that this plant is fully capable of meeting the target removal of sulfur dioxides from flue gas (flow rate : 300-thousand m 3 /h). Recovered by-products, namely ammonium sulfate and ammonium nitrate, from the treatment were actually tested as fertilizers, the result of which was favorable. The sale and distribution of these by-products are already underway. In May 1995, this plant was presented the certificate of authorization by China's State Power Corporation. It is noted that this was the first time a sulfur dioxide removal plant was certified as such in China. (author)

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.

Thermal power plant design and operation

CERN Document Server

Sarkar, Dipak

2015-01-01

Thermal Power Plant: Design and Operation deals with various aspects of a thermal power plant, providing a new dimension to the subject, with focus on operating practices and troubleshooting, as well as technology and design. Its author has a 40-long association with thermal power plants in design as well as field engineering, sharing his experience with professional engineers under various training capacities, such as training programs for graduate engineers and operating personnel. Thermal Power Plant presents practical content on coal-, gas-, oil-, peat- and biomass-fueled thermal power

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.

CSR as Corporate Power. A Communication View Facebook Approach: An Exploratory Study

OpenAIRE

Anca Diana ȘERBAN

2016-01-01

This article aims to operationalize and measure the power of corporate communication and the main strategies that Romanian companies use to communicate their CSR campaigns on Facebook. The study conducts an extensive survey designed to emphasize the corporate communication indicators of power within CSR communication on Facebook and their correlation with the CSR communication strategy used by the first 100 biggest companies in Romania according to their turnover. The most important findings ...

Power Electronics Thermal Management | Transportation Research | NREL

Science.gov (United States)

Power Electronics Thermal Management Power Electronics Thermal Management A photo of water boiling in liquid cooling lab equipment. Power electronics thermal management research aims to help lower the investigates and develops thermal management strategies for power electronics systems that use wide-bandgap

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)

76 FR 53436 - Free Flow Power Corporation; Northland Power Mississippi River LLC; Notice of Competing...

Science.gov (United States)

2011-08-26

... Mississippi River, near the town of Luling, in St. Charles Parish, Louisiana. The sole purpose of a.... 14091-000] Free Flow Power Corporation; Northland Power Mississippi River LLC; Notice of Competing... Mississippi River LLC (Northland) filed preliminary permit applications, pursuant to section 4(f) of the...

76 FR 53427 - Free Flow Power Corporation; Northland Power Mississippi River LLC; Notice of Competing...

Science.gov (United States)

2011-08-26

... Mississippi River, near the town of Killona, in St. Charles Parish, Louisiana. The sole purpose of a.... 14092-000] Free Flow Power Corporation; Northland Power Mississippi River LLC; Notice of Competing... Mississippi River LLC (Northland) filed preliminary permit applications, pursuant to section 4(f) of the...

78 FR 62361 - Green Mountain Power Corporation; Vermont; Otter Creek Hydroelectric Project; Notice of Proposed...

Science.gov (United States)

2013-10-21

... Power Corporation; Vermont; Otter Creek Hydroelectric Project; Notice of Proposed Restricted Service... issuance of a new license for the Otter Creek Hydroelectric Project No. 2558. The programmatic agreement... Agreement would be incorporated into any Order issuing a license. Green Mountain Power Corporation, as...

Thermal Cycling and High Temperature Reverse Bias Testing of Control and Irradiated Gallium Nitride Power Transistors

Science.gov (United States)

Patterson, Richard L.; Boomer, Kristen T.; Scheick, Leif; Lauenstein, Jean-Marie; Casey, Megan; Hammoud, Ahmad

2014-01-01

The power systems for use in NASA space missions must work reliably under harsh conditions including radiation, thermal cycling, and exposure to extreme temperatures. Gallium nitride semiconductors show great promise, but information pertaining to their performance is scarce. Gallium nitride N-channel enhancement-mode field effect transistors made by EPC Corporation in a 2nd generation of manufacturing were exposed to radiation followed by long-term thermal cycling and testing under high temperature reverse bias conditions in order to address their reliability for use in space missions. Result of the experimental work are presented and discussed.

Thermal power plant efficiency enhancement with Ocean Thermal Energy Conversion

International Nuclear Information System (INIS)

Soto, Rodrigo; Vergara, Julio

2014-01-01

In addition to greenhouse gas emissions, coastal thermal power plants would gain further opposition due to their heat rejection distressing the local ecosystem. Therefore, these plants need to enhance their thermal efficiency while reducing their environmental offense. In this study, a hybrid plant based on the principle of Ocean Thermal Energy Conversion was coupled to a 740 MW coal-fired power plant project located at latitude 28°S where the surface to deepwater temperature difference would not suffice for regular OTEC plants. This paper presents the thermodynamical model to assess the overall efficiency gained by adopting an ammonia Rankine cycle plus a desalinating unit, heated by the power plant condenser discharge and refrigerated by cold deep seawater. The simulation allowed us to optimize a system that would finally enhance the plant power output by 25–37 MW, depending on the season, without added emissions while reducing dramatically the water temperature at discharge and also desalinating up to 5.8 million tons per year. The supplemental equipment was sized and the specific emissions reduction was estimated. We believe that this approach would improve the acceptability of thermal and nuclear power plant projects regardless of the plant location. -- Highlights: • An Ocean Thermal Energy Conversion hybrid plant was designed. • The waste heat of a power plant was delivered as an OTEC heat source. • The effect of size and operating conditions on plant efficiency were studied. • The OTEC implementation in a Chilean thermal power plant was evaluated. • The net efficiency of the thermal power plant was increased by 1.3%

Thermal Aspects Related to Power Assemblies

Directory of Open Access Journals (Sweden)

PLESCA, A.

2010-02-01

Full Text Available In many cases when a power assembly based on power semiconductors is used, catastrophic failure is the result of steep temperature gradient in the localized temperature distribution. Hence, an optimal heatsink design for certain industrial applications has become a real necessity. In this paper, the Pro/ENGINEER software with the thermal simulation integrated tool, Pro/MECHANICA, has been used for thermal study of a specific power semiconductor assembly. A series of steady-state and transient thermal simulations have been performed. The experimental tests have confirmed the simulation results. Therefore, the use of specific 3D modeling and simulation software allows to design special power semiconductor assemblies with a better thermal transfer between its heatsink and power electronic components at given operating conditions.

78 FR 26771 - Mesa Wind Power Corporation; Supplemental Notice That Initial Market-Based Rate Filing Includes...

Science.gov (United States)

2013-05-08

... Wind Power Corporation's application for market-based rate authority, with an accompanying rate... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER13-1346-000] Mesa Wind Power Corporation; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for...

Power Electronics Thermal Management R&D

Energy Technology Data Exchange (ETDEWEB)

Moreno, Gilbert; Bennion, Kevin

2016-06-08

This project will develop thermal management strategies to enable efficient and high-temperature wide-bandgap (WBG)-based power electronic systems (e.g., emerging inverter and DC-DC converter designs). The use of WBG-based devices in automotive power electronics will improve efficiency and increase driving range in electric-drive vehicles; however, the implementation of this technology is limited, in part, due to thermal issues. This project will develop system-level thermal models to determine the thermal limitations of current automotive power modules under elevated device temperature conditions. Additionally, novel cooling concepts and material selection will be evaluated to enable high-temperature silicon and WBG devices in power electronics components. WBG devices (silicon carbide [SiC], gallium nitride [GaN]) promise to increase efficiency, but will be driven as hard as possible. This creates challenges for thermal management and reliability.

Churchill Falls (Labrador) Corporation Limited and Twin Falls Power Corporation Limited : 1997 auditors` report and financial statements

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-02-01

The consolidated balance sheet of Churchill Falls (Labrador) Corp. Ltd., and Twin Falls Power Corp. Ltd. for the year 1997 were presented by the Corporation`s auditors, certifying that the statements of income and retained earnings and changes in financial position at year-end were accurate and free of material errors. A summary of significant accounting policies was also provided. In the auditors` view the financial statements from 1997 reflect the financial position of the companies accurately. Corresponding data from 1996 were included to allow for comparisons. tabs.

Solar thermal power: the seamless solar link to the conventional power world

International Nuclear Information System (INIS)

Geyer, Michael; Quaschning, Volker

2000-01-01

This article focuses on solar thermal power generation and describes two solar thermal power concepts, namely, the parabolic trough or solar farm, and the solar central receiver or power tower. Details are given of grid-connected parabolic trough power plants in California and recent developments in collector design and absorber tubes, and the operation of power tower plants with different heat transfer media. Market issues are discussed, and solar thermal power projects under development, and application for support for solar thermal power projects under the Global Environment Facility's Operational Programme by Egypt, India, Iran, Mexico and Morocco are reported

Thermal resistance matrix representation of thermal effects and thermal design in multi-finger power heterojunction bipolar transistors

Institute of Scientific and Technical Information of China (English)

Jin Dong-Yue; Zhang Wan-Rong; Chen Liang; Fu Qiang; Xiao Ying; Wang Ren-Qing; Zhao Xin

2011-01-01

The thermal resistance matrix including self-heating thermal resistance and thermal coupling resistance is presented to describe the thermal effects of multi-finger power heterojunction bipolar transistors. The dependence of thermal resistance matrix on finger spacing is also investigated. It is shown that both self-heating thermal resistance and thermal coupling resistance are lowered by increasing the finger spacing, in which the downward dissipated heat path is widened and the heat flow from adjacent fingers is effectively suppressed. The decrease of self-heating thermal resistance and thermal coupling resistance is helpful for improving the thermal stability of power devices. Furthermore, with the aid of the thermal resistance matrix, a 10-finger power heterojunction bipolar transistor (HBT) with non-uniform finger spacing is designed for high thermal stability. The optimized structure can effectively lower the peak temperature while maintaining a uniformity of the temperature profile at various biases and thus the device effectively may operate at a higher power level.

The news value of Dutch corporate press releases as a predictor of corporate agenda building power

NARCIS (Netherlands)

Schafraad, P.; van Zoonen, W.; Verhoeven, P.

2016-01-01

This study focuses on explaining agenda building power of corporate press releases. The purpose of the study is to investigate to what extent news factor theory can be applied to predict whether a press release generates media attention or not. A content analysis of 823 press releases from 30 of the

KMRR thermal power measurement error estimation

International Nuclear Information System (INIS)

Rhee, B.W.; Sim, B.S.; Lim, I.C.; Oh, S.K.

1990-01-01

The thermal power measurement error of the Korea Multi-purpose Research Reactor has been estimated by a statistical Monte Carlo method, and compared with those obtained by the other methods including deterministic and statistical approaches. The results show that the specified thermal power measurement error of 5% cannot be achieved if the commercial RTDs are used to measure the coolant temperatures of the secondary cooling system and the error can be reduced below the requirement if the commercial RTDs are replaced by the precision RTDs. The possible range of the thermal power control operation has been identified to be from 100% to 20% of full power

The making of a transnational capitalist class: corporate power in the twenty-first century

NARCIS (Netherlands)

Carroll, W.K.; Carson, C.; Fennema, M.; Heemskerk, E.; Sapinski, J.P.

2010-01-01

Throughout the world, there has been a growing wave of interest in global corporate power and the rise of a transnational capitalist class, triggered by economic and political transformations that have blurred national borders and disembedded corporate business from national domiciles. Using social

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.

The central government power generating capacity- reforms and the future

International Nuclear Information System (INIS)

Singh, Rajendra

1995-01-01

The alarming resource gap that the states were facing in 1970's has prompted the Central Government to augment the resources for power generation by creating two new entities in November 1975 viz the National Thermal Power Corporation (NTPC) and National Hydro Power Corporation (NHPC). Few other organisations also exist in central sector which are engaged in power generation like Nuclear Power Corporation (NPC). NTPC being the leading player in the power sector, it can neither be indifferent nor dissociate itself from the reforms sweeping the sector today. The article describes the Central Government's role in power generation, reforms and NTPC and further prospects of NTPC

Concentrating solar thermal power.

Science.gov (United States)

Müller-Steinhagen, Hans

2013-08-13

In addition to wind and photovoltaic power, concentrating solar thermal power (CSP) will make a major contribution to electricity provision from renewable energies. Drawing on almost 30 years of operational experience in the multi-megawatt range, CSP is now a proven technology with a reliable cost and performance record. In conjunction with thermal energy storage, electricity can be provided according to demand. To date, solar thermal power plants with a total capacity of 1.3 GW are in operation worldwide, with an additional 2.3 GW under construction and 31.7 GW in advanced planning stage. Depending on the concentration factors, temperatures up to 1000°C can be reached to produce saturated or superheated steam for steam turbine cycles or compressed hot gas for gas turbine cycles. The heat rejected from these thermodynamic cycles can be used for sea water desalination, process heat and centralized provision of chilled water. While electricity generation from CSP plants is still more expensive than from wind turbines or photovoltaic panels, its independence from fluctuations and daily variation of wind speed and solar radiation provides it with a higher value. To become competitive with mid-load electricity from conventional power plants within the next 10-15 years, mass production of components, increased plant size and planning/operating experience will be accompanied by technological innovations. On 30 October 2009, a number of major industrial companies joined forces to establish the so-called DESERTEC Industry Initiative, which aims at providing by 2050 15 per cent of European electricity from renewable energy sources in North Africa, while at the same time securing energy, water, income and employment for this region. Solar thermal power plants are in the heart of this concept.

77 FR 59679 - Central Vermont Public Service Corporation (Millstone Power Station, Unit 3); Order Approving...

Science.gov (United States)

2012-09-28

... NUCLEAR REGULATORY COMMISSION [NRC-2012-0044; Docket No. 50-423] Central Vermont Public Service Corporation (Millstone Power Station, Unit 3); Order Approving Application Regarding Corporate Restructuring and Conforming Amendment I Dominion Nuclear Connecticut, Inc. (DNC), Central Vermont Public Service...

Churchill Falls (Labrador) Corporation Limited and Twin Falls Power Corporation Limited: Auditor's report and financial statements for the year ended December 31, 1992

International Nuclear Information System (INIS)

1993-01-01

Churchill Falls (Labrador) Corp. Ltd. operates a hydroelectric generating plant and related transmission facilities in Labrador with a rated capacity of 5,428 MW. A power contract with Hydro-Quebec provides for the sale of substantially all of the energy from the plant until 2041. The corporation owns a 33.3% equity interest and a 66.7% voting interest in Twin Falls Power Corp., which has an inoperative 225 MW hydroelectric plant on the Unknown River in Labrador. Financial statements for the two corporations are presented for 1992. Total revenues from sales of power by Churchill Falls in 1992 were $87.4 million, and net income for the year was $26.3 million

Water pollution and thermal power stations

International Nuclear Information System (INIS)

Maini, A.; Harapanahalli, A.B.

1993-01-01

There are a number of thermal power stations dotting the countryside in India for the generation of electricity. The pollution of environment is continuously increasing in the country with the addition of new coal based power stations and causing both a menace and a hazard to the biota. The paper reviews the problems arising out of water pollution from the coal based thermal power stations. (author). 2 tabs

Thermal-hydraulics for space power, propulsion, and thermal management system design

International Nuclear Information System (INIS)

Krotiuk, W.J.

1990-01-01

The present volume discusses thermal-hydraulic aspects of current space projects, Space Station thermal management systems, the thermal design of the Space Station Free-Flying Platforms, the SP-100 Space Reactor Power System, advanced multi-MW space nuclear power concepts, chemical and electric propulsion systems, and such aspects of the Space Station two-phase thermal management system as its mechanical pumped loop and its capillary pumped loop's supporting technology. Also discussed are the startup thaw concept for the SP-100 Space Reactor Power System, calculational methods and experimental data for microgravity conditions, an isothermal gas-liquid flow at reduced gravity, low-gravity flow boiling, computations of Space Shuttle high pressure cryogenic turbopump ball bearing two-phase coolant flow, and reduced-gravity condensation

Power Electronics Thermal Management

Energy Technology Data Exchange (ETDEWEB)

Moreno, Gilberto [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-08-07

Thermal modeling was conducted to evaluate and develop thermal management strategies for high-temperature wide-bandgap (WBG)-based power electronics systems. WBG device temperatures of 175 degrees C to 250 degrees C were modeled under various under-hood temperature environments. Modeling result were used to identify the most effective capacitor cooling strategies under high device temperature conditions.

Nuclear power and other thermal power

International Nuclear Information System (INIS)

Bakke, J.

1978-01-01

Some philosophical aspects of mortality statistics are first briefly mentioued, then the environmental problems of, first, nuclear power plants, then fossil fuelled power plants are summarised. The effects of releases of carbon dioxide, sulphur dioxide and nitrogen oxides are briefly discussed. The possible health effects of radiation from nuclear power plants and those of gaseous and particulate effluents from fossil fuel plants are also discussed. It is pointed out that in choosing between alternative evils the worst course is to make no choice at all, that is, failure to install thermal power plants will lead to isolated domestic burning of fossil fuels which is clearly the worst situation regarding pollution. (JIW)

Strategies for growth of thermal power

International Nuclear Information System (INIS)

Shah, R.K.D.

1998-01-01

The power generating industry in India is at the cross roads. Massive investments are required to achieve GDP growth of 7-8% per annum over the next 10 years. For this, appropriate strategies have to be evolved which will give the country best returns. With coal being the major fuel resource in India, thermal power generation will continue to be the mainstay in the next decade. This paper covers various key issues to be addressed covering the plan and perspectives of thermal power, environmental issues, technology strategies for growth, power policy and R and D. (author)

Joint excitation and reactive power control in thermal power plant

Directory of Open Access Journals (Sweden)

Dragosavac Jasna

2013-01-01

Full Text Available The coordinated voltage and reactive power controller, designed for the thermal power plant, is presented in the paper. A brief explanation of the need for such device is given and justification for commissioning of such equipment is outlined. After short description of the theoretical background of the proposed control design, the achieved features of the commissioned equipment are fully given. Achieved performances are illustrated by recorded reactive power and bus voltage responses after commissioning of the described equipment into the largest thermal power plant in Serbia. As it can be seen in presented records, all design targets are met.

Power Electronics and Thermal Management | Transportation Research | NREL

Science.gov (United States)

Power Electronics and Thermal Management Power Electronics and Thermal Management This is the March Gearhart's testimony. Optical Thermal Characterization Enables High-Performance Electronics Applications New vehicle electronics systems are being developed at a rapid pace, and NREL is examining strategies to

Concentrated solar thermal power - Now

Energy Technology Data Exchange (ETDEWEB)

Aringhoff, R.; Brakmann, G. [Solar Thermal Power Industry Association ESTIA, Avenue de la Fauconnerie 73, 1170 Brussels (Belgium); Geyer, M. [IEA SolarPACES Implementing Agreement, Avenida de la Paz 51, 04720 Aguadulce, Almeria (Spain); Teske, S. [Greenpeace International, Ottho Heldringstraat 5, 1066 AZ Amsterdam (Netherlands)

2005-09-15

This report demonstrates that there are no technical, economic or resource barriers to supplying 5% of the world's electricity needs from solar thermal power by 2040. It is written as practical blueprint to improve understanding of the solar thermal contribution to the world energy supply.

Solar Thermal Power.

Science.gov (United States)

McDaniels, David K.

The different approaches to the generation of power from solar energy may be roughly divided into five categories: distributed collectors; central receivers; biomass; ocean thermal energy conversion; and photovoltaic devices. The first approach (distributed collectors) is the subject of this module. The material presented is designed to…

Concentrated solar thermal power - Now

Energy Technology Data Exchange (ETDEWEB)

Aringhoff, R.; Brakmann, G. [Solar Thermal Power Industry Association ESTIA, Avenue de la Fauconnerie 73, 1170 Brussels (Belgium); Geyer, M. [IEA SolarPACES Implementing Agreement, Avenida de la Paz 51, 04720 Aguadulce, Almeria (Spain); Teske, S. [Greenpeace International, Ottho Heldringstraat 5, 1066 AZ Amsterdam (Netherlands)

2005-09-15

This report demonstrates that there are no technical, economic or resource barriers to supplying 5% of the world's electricity needs from solar thermal power by 2040. It is written as practical blueprint to improve understanding of the solar thermal contribution to the world energy supply.

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

A Lumped Thermal Model Including Thermal Coupling and Thermal Boundary Conditions for High Power IGBT Modules

DEFF Research Database (Denmark)

Bahman, Amir Sajjad; Ma, Ke; Blaabjerg, Frede

2018-01-01

Detailed thermal dynamics of high power IGBT modules are important information for the reliability analysis and thermal design of power electronic systems. However, the existing thermal models have their limits to correctly predict these complicated thermal behavior in the IGBTs: The typically used...... thermal model based on one-dimensional RC lumps have limits to provide temperature distributions inside the device, moreover some variable factors in the real-field applications like the cooling and heating conditions of the converter cannot be adapted. On the other hand, the more advanced three......-dimensional thermal models based on Finite Element Method (FEM) need massive computations, which make the long-term thermal dynamics difficult to calculate. In this paper, a new lumped three-dimensional thermal model is proposed, which can be easily characterized from FEM simulations and can acquire the critical...

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

The law for the Power Reactor and Nuclear Fule Development Corporation

International Nuclear Information System (INIS)

1977-01-01

The Corporation is designated to engage in the independent development of fast breeder and advanced thermal reactors, the production, reprocessing and holding of nuclear fuel materials, and the exploration, mining and ore dressing of nuclear source materials to promoting the development and utilization of atomic energy. These activities are based on the Atomic Energy Basic Law, and limited to the peaceful uses. The basic concepts of a fast breeder reactor and an advanced thermal reactor are defined. A chapter is dedicated to the number, constitution, duties, competence, appointment and dismissal of the officers. The score of business is specified, beginning from the development and research of the reactors and ending with the import, export, purchase and selling of nuclear fuel materials and nuclear source materials. (Okada, K.)

thermal power stations' reliability evaluation in a hydrothermal system

African Journals Online (AJOL)

Dr Obe

A quantitative tool for the evaluation of thermal power stations reliability in a hydrothermal system is presented. ... (solar power); wind (wind power) and the rest, thermal power and ... probability of a system performing its function adequately for ...

Cogeneration feasibility: Otis Elevator Company and Polychrome Corporation. Final report

Energy Technology Data Exchange (ETDEWEB)

1982-05-01

The purpose of this study was to assess the feasibility of cogeneration at Otis Elevator Company and Polychrome Corporation located in Westchester County, New York. Each plant and its associated thermal and electrical load is reviewed. Three basic cycles for the cogeneration are investigated: power only, power generation with waste heat recovery, and combined cycle. Each case was assessed economically, beginning with a screening method to suggest those configurations most likely to be implemented and continuing through an assessment of the regulatory environment for cogeneration and an analysis of rate structures for buy back power, displaced power, and supplementing service. It is concluded that: for a plant designed to supply the combined loads of the two corporations, interconnection costs coupled to the coincidence of load result in unfavorable economics; for separate cogeneration plants, owned and operated by each individual corporation, energy consumption patterns and the current regulatory environment, in particular the existing and proposed cogeneration system rate structures, do not permit viable economics for the proposed plants; but if the proposed cycle were owned and operated by a new entity (neither Otis/Polychrome nor the utility), an economic scheme with marginal financial benefits can be developed and may be worthy of further study. (LEW)

Power Electronics Thermal Management R&D: Annual Report

Energy Technology Data Exchange (ETDEWEB)

Moreno, Gilbert [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-04-08

The objective for this project is to develop thermal management strategies to enable efficient and high-temperature wide-bandgap (WBG)-based power electronic systems (e.g., emerging inverter and DC-DC converter). Device- and system-level thermal analyses are conducted to determine the thermal limitations of current automotive power modules under elevated device temperature conditions. Additionally, novel cooling concepts and material selection will be evaluated to enable high-temperature silicon and WBG devices in power electronics components. WBG devices (silicon carbide [SiC], gallium nitride [GaN]) promise to increase efficiency, but will be driven as hard as possible. This creates challenges for thermal management and reliability.

Environmental effects of thermal power plants

International Nuclear Information System (INIS)

Gerlitzky, M.; Friedrich, R.; Unger, H.

1986-02-01

Reviewing critically the present literature, the effects of thermal power plants on the environment are studied. At first, the loads of the different power plant types are compiled. With regard to the effects of emission reduction proceedings the pollutant emissions are quantified. The second chapter shows the effects on the ecological factors, which could be caused by the most important emission components of thermal power plants. Where it is possible, relations between immissions respectively depositions and their effects on climate, man, flora, fauna and materials will be given. This shows that many effects depend strongly on the local landscape, climate and use of natural resources. Therefore, it appears efficient to ascertain different load limits. The last chapter gives a suggestion for an ecological compatibility test (ECT) of thermal power plants. In modular form the ECT deals with the emission fields, waste heat, pollution burden of air and water, noise, loss of area and aesthetical aspects. Limits depending on local conditions and use of area will be discussed. (orig.) [de

Thermal power measurement apparatus

International Nuclear Information System (INIS)

1981-01-01

Thermal power measurements are important in nuclear power plants, fossil-fuel plants and other closed loop systems such as heat exchangers and chemical reactors. The main object of this invention is to determine the enthalpy of a fluid using only acoustically determined sound speed and correlating the speed with enthalpy. An enthalpy change is measured between two points in the fluid flow: the apparatus is described in detail. (U.K.)

Thermal Power:Focusing on Efficient and Clean Generation

Institute of Scientific and Technical Information of China (English)

无

2009-01-01

History review Before the foundation of New China,there was no thermal power equipment manufacturing industry in China at all.China imported the manufacturing technology of 6-MW and12-MW thermal power units from the former

Cooling towers for thermal power plants

International Nuclear Information System (INIS)

Chaboseau, J.

1987-01-01

After a brief recall on cooling towers testing and construction, this paper presents four examples of very large French nuclear power plant cooling towers, and one of an Australian thermal power plant [fr

Electric power industry restructuring and ROE: The case of Korea Electric Power Corporation

International Nuclear Information System (INIS)

Won, Gu-Hwan

2007-01-01

Korea's electric power industry was previously run by Korea Electric Power Corporation (KEPCO) in a natural monopoly-type structure. As economy of scale was waning in influence and management effectiveness began to increase in importance, KEPCO was divided into six subsidiaries and faced competition beginning in April 2001. This study evaluates the restructuring process for Korea's power industry and analyzes the financial outcomes based on return on equity (ROE). The results show that the ROE ratio increased. In the analysis period (1993-2004), the financial ratio showed a better performance than that before restructuring. However, productivity ratios such as productivity of capital (or gross value added to total assets) and gross value added to property, plant, and equipment decreased compared to the situation before restructuring. It is believed that the results were due to the increased financial leverage of KEPCO. For this reason, KEPCO should make further efforts to manage its debt in a systematic way

Critical success factors for BOT electric power projects in China: Thermal power versus wind power

Energy Technology Data Exchange (ETDEWEB)

Zhao, Zhen-Yu. [School of Business Administration, North China Electric Power University, Beijing 102206 (China); Zuo, Jian; Zillante, George [School of Natural and Built Environments, University of South Australia, Adelaide 5001 (Australia); Wang, Xin-Wei [Shandong Nuclear Power Equipment Manufacturing Co. Ltd, Haiyang, Shandong 265118 (China)

2010-06-15

Chinese electric power industry has adopted Build-Operate-Transfer (BOT) approach in a number of projects to alleviate the pressure of sole state-owned investment. The Chinese government has taken enormous efforts to create an environment to facilitate the application of BOT approach in electric power projects. Moreover, the growing attention on the sustainability issues puts the traditional major source of electricity - thermal power project under more strict scrutiny. As a result, various renewable energy projects, particularly the wind power projects have involved private sector funds. Both thermal power and wind power projects via BOT approach have met with a varying degree of success. Therefore, it is imperative to understand the factors contributing towards the success of both types of BOT power projects. Using an extensive literature survey, this paper identifies 31 success factors under 5 categories for Chinese BOT electric power projects. This is followed by a questionnaire survey to exam relative significance of these factors. The results reveal the different levels of significance of success factors for BOT thermal power projects versus wind power projects. Finally, survey results were analyzed to explore the underlying construction and distributions among the identified success factors. This study provides a valuable reference for all involved parties that are interested in developing BOT electric power projects in China. (author)

Rankine-Brayton engine powered solar thermal aircraft

Science.gov (United States)

Bennett, Charles L [Livermore, CA

2009-12-29

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Rankline-Brayton engine powered solar thermal aircraft

Science.gov (United States)

Bennett, Charles L [Livermore, CA

2012-03-13

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

Numerical Modeling of Water Thermal Plumes Emitted by Thermal Power Plants

Directory of Open Access Journals (Sweden)

Azucena Durán-Colmenares

2016-10-01

Full Text Available This work focuses on the study of thermal dispersion of plumes emitted by power plants into the sea. Wastewater discharge from power stations causes impacts that require investigation or monitoring. A study to characterize the physical effects of thermal plumes into the sea is carried out here by numerical modeling and field measurements. The case study is the thermal discharges of the Presidente Adolfo López Mateos Power Plant, located in Veracruz, on the coast of the Gulf of Mexico. This plant is managed by the Federal Electricity Commission of Mexico. The physical effects of such plumes are related to the increase of seawater temperature caused by the hot water discharge of the plant. We focus on the implementation, calibration, and validation of the Delft3D-FLOW model, which solves the shallow-water equations. The numerical simulations consider a critical scenario where meteorological and oceanographic parameters are taken into account to reproduce the proper physical conditions of the environment. The results show a local physical effect of the thermal plumes within the study zone, given the predominant strong winds conditions of the scenario under study.

Frequency-domain thermal modelling of power semiconductor devices

DEFF Research Database (Denmark)

Ma, Ke; Blaabjerg, Frede; Andresen, Markus

2015-01-01

to correctly predict the device temperatures, especially when considering the thermal grease and heat sink attached to the power semiconductor devices. In this paper, the frequency-domain approach is applied to the modelling of thermal dynamics for power devices. The limits of the existing RC lump...

Power Electronics Thermal Management R&D (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Waye, S.

2014-11-01

This project will investigate and develop thermal-management strategies for wide bandgap (WBG)-based power electronics systems. Research will be carried out to deal with thermal aspects at the module- and system-level. Module-level research will focus on die- and substrate-integrated cooling strategies and heat-transfer enhancement technologies. System-level research will focus on thermal-management strategies for the entire power electronics system to enable smart packaging solutions. One challenge with WBG device-based power electronics is that although losses in the form of heat may be lower, the footprint of the components is also likely to be reduced to reduce cost, weight, and volume. Combined with higher operational temperatures, this creates higher heat fluxes which much be removed from a smaller footprint, requiring advanced cooling strategies.

Virginia Power thermal-hydraulics methods

International Nuclear Information System (INIS)

Anderson, R.C.; Basehore, K.L.; Harrell, J.R.

1987-01-01

Virginia Power's nuclear safety analysis group is responsible for the safety analysis of reload cores for the Surry and North Anna power stations, including the area of core thermal-hydraulics. Postulated accidents are evaluated for potential departure from nucleate boiling violations. In support of these tasks, Virginia Power has employed the COBRA code and the W-3 and WRB-1 DNB correlations. A statistical DNBR methodology has also been developed. The code, correlations and statistical methodology are discussed

China general nuclear power corporation--The recent research and application of the modular technology in nuclear power engineering

International Nuclear Information System (INIS)

Lu Qinwu

2014-01-01

Modular design and construction is one of the distinctive features of the 3"r"d generation nuclear power technology. In order to promote the technological innovations in nuclear power engineering design and construction and develop the self-owned modular technology, China General Nuclear Power Corporation (CGN) has carried out the R and D and application of the modular technology based on the CPR1000-type nuclear power plants, and has made the national-level achievements in the establishment of modular design technology system, development of 3D modular design system and application of modular construction of containment steel liner in the demonstration projects. (author)

Analysis of thermal power calibration method

International Nuclear Information System (INIS)

Zagar, T.; Ravnik, M.; Persic, A.

2000-01-01

The methods for determining fuel element burnup have recently become interesting because of activities related to the shipment of highly enriched fuel elements back to the United States for final disposal before 2009. The most common and practical method for determining fuel element burnup in research reactors is reactor calculation. Experience has shown that burnup calculations become complicated and biased with uncertainties if a long period of reactor operation must be reproduced. Besides this, accuracy of calculated burnup is always limited with accuracy of reactor power calibration, since burnup calculation is based on calculated power density distribution, which is usually expressed in terms of power released per fuel element and normalised to the reactor power It is obvious that reactor thermal power calibration is very important for precise fuel element burnup calculation. Calculated fuel element burnup is linearly dependent on the thermal reactor power. The reactor power level may be determined from measured absolute thermal flux distribution across the core in the horizontal and vertical planes. Flux distributions are measured with activation of cadmium covered and bare foils irradiated by the steady reactor power. But it should be realised that this method is time consuming and not accurate. This method is practical only for zero power reactors and is in practice very seldom performed for other reactors (e.g. for TRIGA reactor in Ljubljana absolute thermal flux distribution was not performed since reactor reconstruction in 1991). In case of power reactors and research reactors in which a temperature rise across the core is produced and measured than a heat balance method is the most common and accurate method of determining the power output of the core. The purpose of this paper is to analyse the accuracy of calorimetric reactor power calibration method and to analyse the influence of control rod position on nuclear detector reading for TRIGA reactors

Japanese aquaculture with thermal water from power plants

International Nuclear Information System (INIS)

Kuroda, T.

1977-01-01

The present level of thermal aquaculture, utilizing thermal water which is waste cooling water from nuclear power plant, in Japan is reported. There are 13 major potential areas for thermal aquaculture in cooperation with conventional type thermal power plants, seven of which are actually operating. Aquaculture facilities of all these are on land, none in the sea. Of these seven centers, those that have already commercialized their nursery methods or are approaching that stage of research and development, are Tohoku Hatsuden Kogyo Ltd., Tsuruga Hama Land Ltd. and Kyushu Rinsan Ltd. Major problems faced specialists in Japanese thermal aquaculture are water temperature, water quality, radioactivity and costs. For keeping the water temperature constant all seasons, cooling or heating by natural sea water may be used. Even negligible amounts of radioactivity that nuclear power plants release into the sea will concentrate in the systems of marine life. A strict precautionary checking routine is used to detect radioactivity in marine life. (Kobatake, H.)

Determining The Optimal Mix of Institutional Geopolitical Power And ASEAN Corporate Governance on the Firm Value of Malaysia’s Multinational Corporations (MNCs

Directory of Open Access Journals (Sweden)

Wan Sallha Yusoff

2018-01-01

Full Text Available The purpose of this paper is to examine the relationship between institutional geopolitics, ASEAN corporate governance quality and the firm value of Malaysia’s multinational corporation (MNC. We used the data of MNCs in Malaysia that were active from 2009 to 2013 as an evidence of MNCs from emerging market economies. Descriptive analysis, factor analysis and panel data analysis have been utilized to test the equation model. We also propose optimization analysis by using differential evolution method to capture the optimal mix of institutional geopolitics and ASEAN_CG on the firm value of MNC. Results reveal that the geopolitics of G7(Canada, France, German, Italy, Japan, Europe, and the United States, BRICS (Brazil, Russia, India, China, and South Africa, and ASEAN (Brunei Darussalam, Cambodia, Indonesia, Lao PDR, Myanmar, Philippines, Singapore, Thailand, Vietnam, and Malaysia are highly correlated with the firm value of Malaysia’s MNC. The power of institutional geopolitics, namely, military, material, and social power, influences firm value negatively and ASEAN_CG moderate the negative influence of institutional geopolitics on the firm value of MNC. Thus, it is importance for corporate management to understand the geopolitical changes of host countries’ and increase the compliance of ASEAN_CG in formulating their market value and segmentation strategies.

Design of a Corporate SDI in Power Sector Using a Formal Model

Directory of Open Access Journals (Sweden)

Italo L. Oliveira

2017-10-01

Full Text Available Geospatial data are essential for the decision-making process. However, obtaining and keeping such data up to date usually require much time and many financial resources. In order to minimize the production costs and incentivize sharing these data, countries are promoting the implementation of Spatial Data Infrastructures (SDI at the different public administration levels. The International Cartographic Association (ICA proposes a formal model that describes the main concepts of an SDI based on three of the five viewpoints of the Reference Model for Open Distributed Processing (RM-ODP. Afterwards, researchers extended ICA’s model to describe, more properly, the actors, hierarchical relationship and interactions related to the policies that drive an SDI. However, the proposed extensions are semantically inconsistent with the original proposal. Moreover, the use of ICA’s formal model and its extensions has not been assessed yet to specify a corporate-level SDI. This study describes the merger of actors and policies proposed by the ICA and its extensions in order to eliminate differences in the semantics or terminology among them. This unified model was applied to specify a corporate SDI for a large Brazilian corporation, the Minas Gerais Power Company (Companhia Energética de Minas Gerais (Cemig, which is comprised of about 200 companies in the power sector. The case study presents part of the specification of the five RM-ODP viewpoints, i.e., the three viewpoints featured in ICA’s formal model (Enterprise, Information, and Computation and the other two viewpoints that make up the RM-ODP (Engineering and Technology. The adapted ICA’s model proved adequate to describe SDI-Cemig. In addition, the case study may serve as an example of the specification and implementation of new SDIs, not only corporate ones, but also of public agencies at any hierarchical level.

Florida Progress Corporation 1991 annual report

International Nuclear Information System (INIS)

Anon.

1992-01-01

Florida Progress Corporation is a utility holding company with assets of 5 billion dollars. Its principal subsidiary is the Florida Power Corporation; others are the Electric Fuels Corporation, the Mid-Continent Life Assurance Company, the Talquin Corporation, the Progress Credit Corporation and Advanced Separation Technologies Incorporated. The annual report describes achievements during the year. To meet growing energy demand Florida Power is building new peaking and base-load generating units, purchasing power from neighbouring utilities and cogenerators, and building more bulk power transmission line capacity in the state. Emphasis has been placed on meeting load growth by demand-site management. Attention is given to balancing energy needs with concerns for the environment, and there is an award-winning recycling program. The Electric Fuels Corporation major area of business is coal mining and transportation services. Advanced Separation Technologies has sold several of its patented ion separation machines. The report includes consolidated financial statements for the year ended 31 December 1991

78 FR 50409 - Kansas Municipal Energy Agency v. Sunflower Electric Power Corporation, Mid-Kansas Electric...

Science.gov (United States)

2013-08-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket Nos. EL13-84-000] Kansas Municipal Energy Agency v. Sunflower Electric Power Corporation, Mid-Kansas Electric Company, LLC, Southwest... 306 of the Federal Power Act, 16 U.S.C. 824e and 825e and Rule 206 of the Federal Energy Regulatory...

Performance analysis of a lunar based solar thermal power system with regolith thermal storage

International Nuclear Information System (INIS)

Lu, Xiaochen; Ma, Rong; Wang, Chao; Yao, Wei

2016-01-01

The manned deep-space exploration is a hot topic of the current space activities. The continuous supply of thermal and electrical energy for the scientific equipment and human beings is a crucial issue for the lunar outposts. Since the night lasts for periods of about 350 h at most locations on the lunar surface, massive energy storage is required for continuous energy supply during the lengthy lunar night and the in-situ resource utilization is demanded. A lunar based solar thermal power system with regolith thermal storage is presented in this paper. The performance analysis is carried out by the finite-time thermodynamics to take into account major irreversible losses. The influences of some key design parameters are analyzed for system optimization. The analytical results shows that the lunar based solar thermal power system with regolith thermal storage can meet the requirement of the continuous energy supply for lunar outposts. - Highlights: • A lunar based solar thermal power system with regolith thermal storage is presented. • The performance analysis is carried out by the finite-time thermodynamics. • The influences of some key design parameters are analyzed.

Featuring Control Power: Corporate Law and Economics Revisited

NARCIS (Netherlands)

A.M. Pacces (Alessio)

2008-01-01

textabstractThis dissertation reappraises the existing framework for economic analysis of corporate law. The standard approach to the legal foundations of corporate governance is based on the ‘law matters’ thesis, according to which corporate law promotes separation of ownership and control by

Design study on the efficiency of the thermal scheme of power unit of thermal power plants in hot climates

Science.gov (United States)

Sedlov, A.; Dorokhov, Y.; Rybakov, B.; Nenashev, A.

2017-11-01

At the stage of pre-proposals unit of the thermal power plants for regions with a hot climate requires a design study on the efficiency of possible options for the structure of the thermal circuit and a set of key parameters. In this paper, the thermal circuit of the condensing unit powerfully 350 MW. The main feature of the external conditions of thermal power plants in hot climates is the elevated temperature of cooling water of the turbine condensers. For example, in the Persian Gulf region as the cooling water is sea water. In the hot season of the year weighted average sea water temperature of 30.9 °C and during the cold season to 22.8 °C. From the turbine part of the steam is supplied to the distillation-desalination plant. In the hot season of the year heat scheme with pressure fresh pair of 23.54 MPa, temperature 570/560 °C and feed pump with electric drive (EDP) is characterized by a efficiency net of 0.25% higher than thermal schem with feed turbine pump (TDP). However, the supplied power unit with PED is less by 11.6 MW. Calculations of thermal schemes in all seasons of the year allowed us to determine the difference in the profit margin of units of the TDP and EDP. During the year the unit with the TDP provides the ability to obtain the profit margin by 1.55 million dollars more than the unit EDP. When using on the market subsidized price of electricity (Iran) marginal profit of a unit with TDP more at 7.25 million dollars.

Availability statistics for thermal power plants

International Nuclear Information System (INIS)

1989-01-01

Denmark, Finland and Sweden have adopted almost the same methods of recording and calculation of availability data. For a number of years comparable availability and outage data for thermal power have been summarized and published in one report. The purpose of the report now presented for 1989 containing general statistical data is to produce basic information on existing kinds of thermal power in the countries concerned. With this information as a basis additional and more detailed information can be exchanged in direct contacts between bodies in the above mentioned countries according to forms established for that purpose. The report includes fossil steam power, nuclear power and gas turbines. The information is presented in separate diagrams for each country, but for plants burning fossil fuel also in a joint NORDEL statistics with data grouped according to type of fuel used. The grouping of units into classes of capacity has been made in accordance with the classification adopted by UNIPEDE/WEC. Values based on energy have been adopted as basic availability data. The same applies to the preference made in the definitions outlined by UNIPEDE and UNIPEDE/WEC. Some data based on time have been included to make possible comparisons with certain international values and for further illustration of the performance. For values given in the report, the definitions in the NORDEL document ''Concepts of Availability for Thermal Power, September 1977'', have been applied. (author)

Mathematical Safety Assessment Approaches for Thermal Power Plants

Directory of Open Access Journals (Sweden)

Zong-Xiao Yang

2014-01-01

Full Text Available How to use system analysis methods to identify the hazards in the industrialized process, working environment, and production management for complex industrial processes, such as thermal power plants, is one of the challenges in the systems engineering. A mathematical system safety assessment model is proposed for thermal power plants in this paper by integrating fuzzy analytical hierarchy process, set pair analysis, and system functionality analysis. In the basis of those, the key factors influencing the thermal power plant safety are analyzed. The influence factors are determined based on fuzzy analytical hierarchy process. The connection degree among the factors is obtained by set pair analysis. The system safety preponderant function is constructed through system functionality analysis for inherence properties and nonlinear influence. The decision analysis system is developed by using active server page technology, web resource integration, and cross-platform capabilities for applications to the industrialized process. The availability of proposed safety assessment approach is verified by using an actual thermal power plant, which has improved the enforceability and predictability in enterprise safety assessment.

Tasks of a power engineer in future thermal power plants

International Nuclear Information System (INIS)

Freymeyer, P.; Scherschmidt, F.

1982-01-01

Today already the power plants provide plenty of tasks and problems to the electrical engineer in the fields of power and conductive engineering. A completely new orientation of power engineering leads to larger, more complex system and even to systems unknown so far. In conductive engineering entirely new solutions have come in view. There are a lot of interesting topics for the electrical engineer in the rearrangement and advance into virgin territory of thermal power plants. (orig.) [de

ESTIMATION OF THERMAL PARAMETERS OF POWER BIPOLAR TRANSISTORS BY THE METHOD OF THERMAL RELAXATION DIFFERENTIAL SPECTROMETRY

Directory of Open Access Journals (Sweden)

V. S. Niss

2015-01-01

Full Text Available Thermal performance of electronic devices determines the stability and reliability of the equipment. This leads to the need for a detailed thermal analysis of semiconductor devices. The goal of the work is evaluation of thermal parameters of high-power bipolar transistors in plastic packages TO-252 and TO-126 by a method of thermal relaxation differential spectrometry. Thermal constants of device elements and distribution structure of thermal resistance defined as discrete and continuous spectra using previously developed relaxation impedance spectrometer. Continuous spectrum, based on higher-order derivatives of the dynamic thermal impedance, follows the model of Foster, and discrete to model of Cauer. The structure of sample thermal resistance is presented in the form of siх-chain electro-thermal RC model. Analysis of the heat flow spreading in the studied structures is carried out on the basis of the concept of thermal diffusivity. For transistor structures the area and distribution of the heat flow cross-section are determined. On the basis of the measurements the thermal parameters of high-power bipolar transistors is evaluated, in particular, the structure of their thermal resistance. For all of the measured samples is obtained that the thermal resistance of the layer planting crystal makes a defining contribution to the internal thermal resistance of transistors. In the transition layer at the border of semiconductor-solder the thermal resistance increases due to changes in the mechanism of heat transfer. Defects in this area in the form of delamination of solder, voids and cracks lead to additional growth of thermal resistance caused by the reduction of the active square of the transition layer. Method of thermal relaxation differential spectrometry allows effectively control the distribution of heat flow in high-power semiconductor devices, which is important for improving the design, improve the quality of landing crystals of power

CORPORATE FEED WITH DUAL SEGMENT CIRCULAR POLARIZED ARRAY RECTENNA FOR LOW POWER RF ENERGY HARVESTING

Directory of Open Access Journals (Sweden)

CHIA CHAO KANG

2016-06-01

Full Text Available This paper focuses on the investigation of the level powers that can be scavenged from the ambient environment by using corporate feed with dual segment circular polarized antenna array . It will converts the received power to direct current (DC. Being a circular polarized antenna, it has higher inductance per unit area, a good Q-factor and compact capability. The design of corporate-series feed rectenna array is to achieve a high gain antenna and maximize the RF energy received by the rectenna system at ultra low power levels. The entire structure was investigated using a combination of harmonic balance nonlinear analysis and full wave electromagnetic field analysis. The results show that 5.0 dBi gain for circular polarized antenna array can be achieved at frequency 956 MHz. When the input power of 20 dBm fed into the transmitting antenna, the maximum distance for radio frequency (RF harvesting is 5.32m. The output DC voltage for various values of incident RF power is also presented. There are noticed reasonable agreements between the simulated and measured result and the works concludes that the investigation of RF energy harvesting system was successful.

Thermodynamic analysis of thermal efficiency and power of Minto engine

International Nuclear Information System (INIS)

He, Wei; Hou, Jingxin; Zhang, Yang; Ji, Jie

2011-01-01

Minto engine is a kind of liquid piston heat engine that operates on a small temperature gradient. But there is no power formula for it yet. And its thermal efficiency is low and formula sometimes is misused. In this paper, deriving the power formula and simplifying the thermal efficiency formula of Minto engine based on energy distribution analysis will be discussed. To improve the original Minto engine, a new design of improved Minto engine is proposed and thermal efficiency formula and power formula are also given. A computer program was developed to analyze thermal efficiency and power of original and improved Minto engines operating between low and high-temperature heat sources. The simulation results show that thermal efficiency of improved Minto engine can reach over 7% between 293.15 K and 353.15 K which is much higher than that of original one; the temperature difference between upper and lower containers is lower than half of that between low and high temperature of heat sources when the original Minto engines output the maximum power; on the contrary, it is higher in the improved Minto engines. -- Highlights: ► The thermal efficiency formula of Minto engine is simplified and the power formula is established. ► A high-powered design of improved Minto engine is proposed. ► A computer simulation program based on real operating environment is developed.

Solar thermal power plants simulation using the TRNSYS software

Energy Technology Data Exchange (ETDEWEB)

Popel, O.S.; Frid, S.E.; Shpilrain, E.E. [Institute for High Temperatures, Russian Academy of Sciences (IVTAN), Moscow (Russian Federation)

1999-03-01

The paper describes activity directed on the TRNSYS software application for mathematical simulation of solar thermal power plants. First stage of developments has been devoted to simulation and thermodynamic analysis of the Hybrid Solar-Fuel Thermal Power Plants (HSFTPP) with gas turbine installations. Three schemes of HSFTPP, namely: Gas Turbine Regenerative Cycle, Brayton Cycle with Steam Injection and Combined Brayton-Rankine Cycle,- have been assembled and tested under the TRNSYS. For this purpose 18 new models of the schemes components (gas and steam turbines, compressor, heat-exchangers, steam generator, solar receiver, condenser, controllers, etc) have been elaborated and incorporated into the TRNSYS library of 'standard' components. The authors do expect that this initiative and received results will stimulate experts involved in the mathematical simulation of solar thermal power plants to join the described activity to contribute to acceleration of development and expansion of 'Solar Thermal Power Plants' branch of the TRNSYS. The proposed approach could provide an appropriate basis for standardization of analysis, models and assumptions for well-founded comparison of different schemes of advanced solar power plants. (authors)

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

Exergy Analysis of Operating Lignite Fired Thermal Power Plant

Directory of Open Access Journals (Sweden)

K. Murugesan

2009-01-01

Full Text Available The energy assessment must be made through the energy quantity as well as the quality. But the usual energy analysisevaluates the energy generally on its quantity only. However, the exergy analysis assesses the energy on quantity as well asthe quality. The aim of the exergy analysis is to identify the magnitudes and the locations of real energy losses, in order toimprove the existing systems, processes or components. The present paper deals with an exergy analysis performed on anoperating 50MWe unit of lignite fired steam power plant at Thermal Power Station-I, Neyveli Lignite Corporation Limited,Neyveli, Tamil Nadu, India. The exergy losses occurred in the various subsystems of the plant and their components havebeen calculated using the mass, energy and exergy balance equations. The distribution of the exergy losses in several plantcomponents during the real time plant running conditions has been assessed to locate the process irreversibility. The Firstlaw efficiency (energy efficiency and the Second law efficiency (exergy efficiency of the plant have also been calculated.The comparison between the energy losses and the exergy losses of the individual components of the plant shows that themaximum energy losses of 39% occur in the condenser, whereas the maximum exergy losses of 42.73% occur in the combustor.The real losses of energy which has a scope for the improvement are given as maximum exergy losses that occurredin the combustor.

Power Electronics Thermal Management Research: Annual Progress Report

Energy Technology Data Exchange (ETDEWEB)

Moreno, Gilberto [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-19

The objective for this project is to develop thermal management strategies to enable efficient and high-temperature wide-bandgap (WBG)-based power electronic systems (e.g., emerging inverter and DC-DC converter). Reliable WBG devices are capable of operating at elevated temperatures (≥ 175 °Celsius). However, packaging WBG devices within an automotive inverter and operating them at higher junction temperatures will expose other system components (e.g., capacitors and electrical boards) to temperatures that may exceed their safe operating limits. This creates challenges for thermal management and reliability. In this project, system-level thermal analyses are conducted to determine the effect of elevated device temperatures on inverter components. Thermal modeling work is then conducted to evaluate various thermal management strategies that will enable the use of highly efficient WBG devices with automotive power electronic systems.

Solar Probe Plus MAG Sensor Thermal Design for Low Heater Power and Extreme Thermal Environment

Science.gov (United States)

Choi, Michael K.

2015-01-01

The heater power available for the Solar Probe Plus FIELDS MAG sensor is less than half of the heritage value for other missions. Nominally the MAG sensors are in the spacecraft's umbra. In the worst hot case, approximately 200 spacecraft communication downlinks, up to 10 hours each, are required at 0.7 AU. These downlinks require the spacecraft to slew 45 deg. about the Y-axis, exposing the MAG sensors and boom to sunlight. This paper presents the thermal design to meet the MAG sensor thermal requirements in the extreme thermal environment and with low heater power. A thermal balance test on the MAG sensor engineering model has verified the thermal design and correlated the thermal model for flight temperature predictions.

Recycled Thermal Energy from High Power Light Emitting Diode Light Source.

Science.gov (United States)

Ji, Jae-Hoon; Jo, GaeHun; Ha, Jae-Geun; Koo, Sang-Mo; Kamiko, Masao; Hong, JunHee; Koh, Jung-Hyuk

2018-09-01

In this research, the recycled electrical energy from wasted thermal energy in high power Light Emitting Diode (LED) system will be investigated. The luminous efficiency of lights has been improved in recent years by employing the high power LED system, therefore energy efficiency was improved compared with that of typical lighting sources. To increase energy efficiency of high power LED system further, wasted thermal energy should be re-considered. Therefore, wasted thermal energy was collected and re-used them as electrical energy. The increased electrical efficiency of high power LED devices was accomplished by considering the recycled heat energy, which is wasted thermal energy from the LED. In this work, increased electrical efficiency will be considered and investigated by employing the high power LED system, which has high thermal loss during the operating time. For this research, well designed thermoelement with heat radiation system was employed to enhance the collecting thermal energy from the LED system, and then convert it as recycled electrical energy.

Water cooling thermal power measurement in a vacuum diffusion pump

Directory of Open Access Journals (Sweden)

Luís Henrique Cardozo Amorin

2012-04-01

Full Text Available Diffusion vacuum pumps are used both in industry and in laboratory science for high vacuum production. For its operation they must be refrigerated, and it is done by circulating water in open circuit. Considering that, vacuum systems stays operating by hours, the water consumption may be avoided if the diffusion vacuum pumps refrigeration were done in closed circuit. However, it is necessary to know the diffusion vacuum pump thermal power (the heat transferred to circulate water by time units to implement one of these and get in the refrigeration system dimension. In this paper the diffusion vacuum pump thermal power was obtained by measuring water flow and temperature variation and was calculated through the heat quantity variation equation time function. The thermal power value was 935,6 W, that is 397 W smaller and 35 W bigger than, respectively, the maximum and minimum diffusion pump thermal power suggested by its operation manual. This procedure have been shown useful to precisely determine the diffusion pump thermal power or of any other system that needs to be refrigerated in water closed circuit.

Japanese aquaculture: use of thermal water from power plant

International Nuclear Information System (INIS)

Kuroda, Takeya

1983-01-01

There is some merit of thermal water from power plants in the effect to marine life. Since 1963, the research and development on the aquaculture using this warm water have been carried out at some twenty power plants, seven nuclear and thirteen thermal, some of which are now in the commercial stage. These fish farming projects are operated variously from seed to adult fish production. They can also be classified as land and sea facilities, conforming to the characteristics of the respective sea areas. The current situation in this field and the future prospect are described: thermal aquaculture including seed production and adult fish farming; the projects in nuclear and thermal power plants, respectively; future problems in the facilities, breeding environment and marine life for cultivation. (Mori, K.)

Applicability of advanced automotive heat engines to solar thermal power

Science.gov (United States)

Beremand, D. G.; Evans, D. G.; Alger, D. L.

The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program.

Power and Thermal Management of System-on-Chip

DEFF Research Database (Denmark)

Liu, Wei

, are necessary at the chip design level. In this work, we investigate the power and thermal management of System-on- Chips (SoCs). Thermal analysis is performed in a SPICE simulation approach based on the electrical-thermal analogy. We investigate the impact of inter- connects on heat distribution...

A self-adaptive thermal switch array for rapid temperature stabilization under various thermal power inputs

International Nuclear Information System (INIS)

Geng, Xiaobao; Patel, Pragnesh; Narain, Amitabh; Meng, Dennis Desheng

2011-01-01

A self-adaptive thermal switch array (TSA) based on actuation by low-melting-point alloy droplets is reported to stabilize the temperature of a heat-generating microelectromechanical system (MEMS) device at a predetermined range (i.e. the optimal working temperature of the device) with neither a control circuit nor electrical power consumption. When the temperature is below this range, the TSA stays off and works as a thermal insulator. Therefore, the MEMS device can quickly heat itself up to its optimal working temperature during startup. Once this temperature is reached, TSA is automatically turned on to increase the thermal conductance, working as an effective thermal spreader. As a result, the MEMS device tends to stay at its optimal working temperature without complex thermal management components and the associated parasitic power loss. A prototype TSA was fabricated and characterized to prove the concept. The stabilization temperatures under various power inputs have been studied both experimentally and theoretically. Under the increment of power input from 3.8 to 5.8 W, the temperature of the device increased only by 2.5 °C due to the stabilization effect of TSA

Power Loss Calculation and Thermal Modelling for a Three Phase Inverter Drive System

Directory of Open Access Journals (Sweden)

Z. Zhou

2005-12-01

Full Text Available Power losses calculation and thermal modelling for a three-phase inverter power system is presented in this paper. Aiming a long real time thermal simulation, an accurate average power losses calculation based on PWM reconstruction technique is proposed. For carrying out the thermal simulation, a compact thermal model for a three-phase inverter power module is built. The thermal interference of adjacent heat sources is analysed using 3D thermal simulation. The proposed model can provide accurate power losses with a large simulation time-step and suitable for a long real time thermal simulation for a three phase inverter drive system for hybrid vehicle applications.

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.

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.

A review on lithium-ion power battery thermal management technologies and thermal safety

Science.gov (United States)

An, Zhoujian; Jia, Li; Ding, Yong; Dang, Chao; Li, Xuejiao

2017-10-01

Lithium-ion power battery has become one of the main power sources for electric vehicles and hybrid electric vehicles because of superior performance compared with other power sources. In order to ensure the safety and improve the performance, the maximum operating temperature and local temperature difference of batteries must be maintained in an appropriate range. The effect of temperature on the capacity fade and aging are simply investigated. The electrode structure, including electrode thickness, particle size and porosity, are analyzed. It is found that all of them have significant influences on the heat generation of battery. Details of various thermal management technologies, namely air based, phase change material based, heat pipe based and liquid based, are discussed and compared from the perspective of improving the external heat dissipation. The selection of different battery thermal management (BTM) technologies should be based on the cooling demand and applications, and liquid cooling is suggested being the most suitable method for large-scale battery pack charged/discharged at higher C-rate and in high-temperature environment. The thermal safety in the respect of propagation and suppression of thermal runaway is analyzed.

The Impact of Power Switching Devices on the Thermal Performance of a 10 MW Wind Power NPC Converter

Directory of Open Access Journals (Sweden)

Ke Ma

2012-07-01

Full Text Available Power semiconductor switching devices play an important role in the performance of high power wind energy generation systems. The state-of-the-art device choices in the wind power application as reported in the industry include IGBT modules, IGBT press-pack and IGCT press-pack. Because of significant deviation in the packaging structure, electrical characteristics, as well as thermal impedance, these available power switching devices may have various thermal cycling behaviors, which will lead to converter solutions with very different cost, size and reliability performance. As a result, this paper aimed to investigate the thermal related characteristics of some important power switching devices. Their impact on the thermal cycling of a 10 MW three-level Neutral-Point-Clamped wind power converter is then evaluated under various operating conditions; the main focus will be on the grid connected inverter. It is concluded that the thermal performances of the 3L-NPC wind power converter can be significantly changed by the power device technology as well as their parallel configurations.

Balancing corporate power: a new Federalist paper.

Science.gov (United States)

Handy, C

1992-01-01

In an effort to govern their increasingly complex organizations, chief executives in some of today's largest corporations are turning to one of the world's oldest political philosophies-federalism. Given that organizations are seen more and more as minisocieties, the prospect of applying political principles to management makes a great deal of sense. Federalism is particularly appropriate because it offers a well-recognized system for dealing with paradoxes of power and control: the need to make things big by keeping them small; to encourage autonomy but within bounds; and to combine variety and shared purpose, individuality and partnership, local and global. As London Business School professor Charles Handy explains it, federalism responds to these paradoxes by balancing power among those in the center of the organization, those in the centers of expertise, and those in the center of the action--the operating businesses. The centers of federal organizations meet regularly, but they do not need to live together. Doing so would concentrate too much power in one place, whereas federalism gets its strength and energy from spreading responsibility across many decision points. Guided by five principles, federalism avoids the risks of autocracy and the overcontrol of a central bureaucracy. It ensures a measure of democracy and creates a "dispersed center" that is more a network than a place. That's why Asea Brown Boveri CEO Percy Barnevik calls his sprawling "multi-domestic" enterprise of 1,100 separate companies and 210,000 employees a federation. It succeeds because the independent bits, be they individuals, clusters, or business units, know they are part of the greater whole.

CSR as Corporate Power. A Communication View Facebook Approach: An Exploratory Study

Directory of Open Access Journals (Sweden)

Anca Diana ȘERBAN

2016-05-01

Full Text Available This article aims to operationalize and measure the power of corporate communication and the main strategies that Romanian companies use to communicate their CSR campaigns on Facebook. The study conducts an extensive survey designed to emphasize the corporate communication indicators of power within CSR communication on Facebook and their correlation with the CSR communication strategy used by the first 100 biggest companies in Romania according to their turnover. The most important findings refer to the practice of Romanian companies of using their Facebook pages, primarily in order to expand their market, and less for reaching the confidence of their stakeholders. Thus, they profess their preference for visibility against trust. Romanian companies mainly use the self-centered strategy to communicate their CSR actions on Facebook, which means that the indicatives „relationship” and „co-creation” are very weak from the company’s point of view. The resistance to power is strong on the stakeholders’ side. As a result, it can be observed that there is a big pressure from the stakeholders’ point of view concerning the CSR communication on Facebook, in Romania. While companies try to sell their products or services through Facebook, stakeholders try to establish a relationship and consolidate a trust liaison with the companies they choose to buy from. In this context, it can be acknowledged that companies would rather respond to stakeholders’ questions or inquiries, than be proactive and anticipate some of their needs or complaints.

Exploitation of Renewable Energy--A Strategic Choice for Sustainable Development of Power Industry

Institute of Scientific and Technical Information of China (English)

Zhou Dabing

2005-01-01

Since China is being faced with the pressure of energy shortage and environmental conservation, the power industry in China has to actively develop the renewable energy for electricity generation while raising the utilization efficiency of conventional energy. In view of such facts, China Guodian Corporation decided on a development strategy of giving priority to green power, such as wind power. Based on the national planning of wind power development, the corporation set out its own target of installing wind power capacity of 1500 MW by the end of 2010, and is adopting appropriate measures including promoting the localization of wind turbines and developing hydropower, thermal power and wind power simultaneously. Moreover, it put some relevant suggestions.

Demonstration test of electron beam flue gas treatment pilot plant of a coal fired thermal power station

International Nuclear Information System (INIS)

Doi, Yoshitaka; Hayashi, Kazuaki; Izutsu, Masahiro; Watanabe, Shigeharu; Namba, Hideki; Tokunaga, Okihiro; Hashimoto, Shoji; Tanaka, Tadashi; Ogura, Yoshimi.

1995-01-01

The Japan Atomic Energy Research Institute, Chubu Electric Power Company and Ebara Corporation jointly constructed a pilot plant for electron beam flue gas treatment (dry process) capable of treating 12,000 m 3 /h (NTP) of flue gas from a coal fired boiler, at Shin-Nagoya Thermal Power Station, Chubu Electric Power Company. Various tests carried out at the plant over a period extending one year verified the followings. By appropriately controlling parameters such as electron beam dosage, flue gas temperature, and ammonia stoichiometric amount, highly efficient simultaneous SO 2 and NOx removal from flue gas was achieved under all gas conditions, equal to or more efficient than that by the highest level conventional treatment. The operation of the pilot plant was stable and trouble-free over a long term, and the operation and the process was easy to operate and control. By-products (ammonium sulfate and ammonium nitrate) produced by the flue gas treatment were proven to have superior quality, equivalent to that of market-available nitrogen fertilizers. These by-products had been registered as by-product nitrogen fertilizers. (author)

Power Admission Control with Predictive Thermal Management in Smart Buildings

DEFF Research Database (Denmark)

Yao, Jianguo; Costanzo, Giuseppe Tommaso; Zhu, Guchuan

2015-01-01

This paper presents a control scheme for thermal management in smart buildings based on predictive power admission control. This approach combines model predictive control with budget-schedulability analysis in order to reduce peak power consumption as well as ensure thermal comfort. First...

Thermal analysis of multi-MW two-level wind power converter

DEFF Research Database (Denmark)

Zhou, Dao; Blaabjerg, Frede; Mogens, Lau

2012-01-01

In this paper, the multi-MW wind turbine of partial-scale and full-scale two-level power converter with DFIG and direct-drive PMSG are designed and compared in terms of their thermal performance. Simulations of different configurations regarding loss distribution and junction temperature...... in the power device in the whole range of wind speed are presented and analyzed. It is concluded that in both partial-scale and full-scale power converter the most thermal stressed power device in the generator-side converter will have higher mean junction temperature and larger junction temperature...... fluctuation compared to grid-side converter at the rated wind speed. Moreover, the thermal performance of the generator-side converter in the partial-scale power converter becomes crucial around the synchronous operating point and should be considered carefully....

Thermal energy storage for CSP (Concentrating Solar Power)

Science.gov (United States)

Py, Xavier; Sadiki, Najim; Olives, Régis; Goetz, Vincent; Falcoz, Quentin

2017-07-01

The major advantage of concentrating solar power before photovoltaic is the possibility to store thermal energy at large scale allowing dispatchability. Then, only CSP solar power plants including thermal storage can be operated 24 h/day using exclusively the solar resource. Nevertheless, due to a too low availability in mined nitrate salts, the actual mature technology of the two tanks molten salts cannot be applied to achieve the expected international share in the power production for 2050. Then alternative storage materials are under studies such as natural rocks and recycled ceramics made from industrial wastes. The present paper is a review of those alternative approaches.

Thermal energy storage for CSP (Concentrating Solar Power

Directory of Open Access Journals (Sweden)

Py Xavier

2017-01-01

Full Text Available The major advantage of concentrating solar power before photovoltaic is the possibility to store thermal energy at large scale allowing dispatchability. Then, only CSP solar power plants including thermal storage can be operated 24 h/day using exclusively the solar resource. Nevertheless, due to a too low availability in mined nitrate salts, the actual mature technology of the two tanks molten salts cannot be applied to achieve the expected international share in the power production for 2050. Then alternative storage materials are under studies such as natural rocks and recycled ceramics made from industrial wastes. The present paper is a review of those alternative approaches.

Continuous hydrino thermal power system

Energy Technology Data Exchange (ETDEWEB)

Mills, Randell L.; Zhao, Guibing; Good, William [BlackLight Power, Inc., 493 Old Trenton Road, Cranbury, NJ 08512 (United States)

2011-03-15

The specifics of a continuous hydrino reaction system design are presented. Heat from the hydrino reactions within individual cells provide both reactor power and the heat for regeneration of the reactants. These processes occur continuously and the power from each cell is constant. The conversion of thermal power to electrical power requires the use of a heat engine exploiting a cycle such as a Rankine, Brayton, Stirling, or steam-engine cycle. Due to the temperatures, economy goal, and efficiency, the Rankine cycle is the most practical and can produce electricity at 30-40% efficiency with a component capital cost of about $300 per kW electric. Conservatively, assuming a conversion efficiency of 25% the total cost with the addition of the boiler and chemical components is estimated at $1064 per kW electric. (author)

Continuous hydrino thermal power system

International Nuclear Information System (INIS)

Mills, Randell L.; Zhao, Guibing; Good, William

2011-01-01

The specifics of a continuous hydrino reaction system design are presented. Heat from the hydrino reactions within individual cells provide both reactor power and the heat for regeneration of the reactants. These processes occur continuously and the power from each cell is constant. The conversion of thermal power to electrical power requires the use of a heat engine exploiting a cycle such as a Rankine, Brayton, Stirling, or steam-engine cycle. Due to the temperatures, economy goal, and efficiency, the Rankine cycle is the most practical and can produce electricity at 30-40% efficiency with a component capital cost of about $300 per kW electric. Conservatively, assuming a conversion efficiency of 25% the total cost with the addition of the boiler and chemical components is estimated at $1064 per kW electric.

Thermal power terms in the Einstein-dilaton system

International Nuclear Information System (INIS)

Zuo, Fen

2014-01-01

We employ the gauge/string duality to study the thermal power terms of various thermodynamic quantities in gauge theories and the renormalized Polyakov loop above the deconfinement phase transition. We restrict ourselves to the five-dimensional Einstein gravity coupled to a single scalar, the dilaton. The asymptotic solutions of the system for a general dilaton potential are employed to study the power contributions of various quantities. If the dilaton is dual to the dimension-4 operator TrF μν 2 , no power corrections would be generated. Then the thermal quantities approach their asymptotic values much more quickly than those observed in lattice simulation. When the dimension of the dual operator is different from 4, various power terms are generated. The lowest power contributions to the thermal quantities are always quadratic in the dilaton, while that of the Polyakov loop is linear. As a result, the quadratic terms in inverse temperature for both the trace anomaly and the Polyakov loop, observed in lattice simulation, cannot be implemented consistently in the system. This is in accordance with the field theory expectation, where no gauge-invariant operator can accommodate such contributions. Two simple models, where the dilaton is dual to operators with different dimensions, are studied in detail to clarify the conclusion.

Application of the thermal efficiency analysis software 'EgWin' at existing power plants

International Nuclear Information System (INIS)

Koda, E.; Takahashi, T.; Nakao, Y.

2008-01-01

'EgWin' is the general purpose software to analyze a thermal efficiency of power system developed in CRIEPI. This software has been used to analyze the existing power generation unit of 30 or more, and the effectiveness has been confirmed. In thermal power plants, it was used for the clarification of the thermal efficiency decrease factor and the quantitative estimation of the influence that each factor gave to the thermal efficiency of the plant. Also it was used for the quantitative estimation of the effect by the operating condition change and the facility remodeling in thermal power, atomic energy, and geothermal power plants. (author)

Solar thermal power meeting - Proceedings

International Nuclear Information System (INIS)

2011-07-01

This document summarizes the presentations and debates of the first edition of the Solar thermal power meeting. Content: 1 - Opening talk (Jean-Louis BAL, SER); 2 - Solar thermal power, European and global road-maps (Cedric Philibert, IEA; Mariangels Perez Latorre, Estela); 3 - first round-table on the international development of solar energy (Philippe Lorec, DGEC France; Said Mouline, Aderee Morocco; Obaid Amrane, Masen Morocco; Kawther Lihidheb, ANME Tunisia; Abdelaziz Boumahra, Rouiba Eclairage, Algeria; Badis Derradji, NEAL Algeria; Yao Azoumah, Lesee, 2IE Foundation Burkina Faso; Mamadou Amadou Kane, MPEM Mauritania; Jean-Charles Mulet, Bertin Technologies); 4 - Second round-table on the French solar thermal offer for export (Georgina Grenon, DGEC; Stephanie Bouzigueseschmann, DG Tresor; Armand Pineda, Alstom; Florent Brunet, Mena-Areva; Roger Pujol, CNIM; Gilles David, Enertime; Michel Wohrer, Saed; Mathieu Vrinat, Sogreah; Marc Benmarraze, Solar Euromed; 5 - Presentation of Amisole - Moroccan association of solar and wind industries (Ahmed Squalli, Amisole); 6 - Third round-table on French research at the solar industry service (Gilles Flamant, Promes Lab. CNRS; Francois Moisan, Ademe; Tahar Melliti, CGI; Andre Joffre, Derbi; Michel Wohrer, Capenergies; 7 - Fourth round table on projects financing (Vincent Girard, Loan Officer BEI; Bertrand Marchais, Miga World Bank; Philippe Meunier, CDC Climat Groupe Caisse des Depots; Christian de Gromard, AFD; Laurent Belouze, Natixis; Piotr Michalowski, Loan Officer BEI); 8 - Closing of the meeting (Roger Pujol, SER)

Solar thermal power system

Science.gov (United States)

Bennett, Charles L.

2010-06-15

A solar thermal power generator includes an inclined elongated boiler tube positioned in the focus of a solar concentrator for generating steam from water. The boiler tube is connected at one end to receive water from a pressure vessel as well as connected at an opposite end to return steam back to the vessel in a fluidic circuit arrangement that stores energy in the form of heated water in the pressure vessel. An expander, condenser, and reservoir are also connected in series to respectively produce work using the steam passed either directly (above a water line in the vessel) or indirectly (below a water line in the vessel) through the pressure vessel, condense the expanded steam, and collect the condensed water. The reservoir also supplies the collected water back to the pressure vessel at the end of a diurnal cycle when the vessel is sufficiently depressurized, so that the system is reset to repeat the cycle the following day. The circuital arrangement of the boiler tube and the pressure vessel operates to dampen flow instabilities in the boiler tube, damp out the effects of solar transients, and provide thermal energy storage which enables time shifting of power generation to better align with the higher demand for energy during peak energy usage periods.

A Novel 3D Thermal Impedance Model for High Power Modules Considering Multi-layer Thermal Coupling and Different Heating/Cooling Conditions

DEFF Research Database (Denmark)

Bahman, Amir Sajjad; Ma, Ke; Blaabjerg, Frede

2015-01-01

accurate temperature estimation either vertically or horizontally inside the power devices is still hard to identify. This paper investigates the thermal behavior of high power module in various operating conditions by means of Finite Element Method (FEM). A novel 3D thermal impedance network considering......Thermal management of power electronic devices is essential for reliable performance especially at high power levels. One of the most important activities in the thermal management and reliability improvement is acquiring the temperature information in critical points of the power module. However...

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.

Upgrading of electrostatic precipitators in old thermal power plant

Energy Technology Data Exchange (ETDEWEB)

Gurumurthy, H V

1987-02-01

Indian thermal power stations installed in the 60's and earlier had dust collectors whose efficiency was well below the acceptable level of emission under the Air (Prevention and Control of Pollution) Act 1981. This necessitates the need for higher efficiency dust collectors to be installed in old thermal power stations. Further, the poor quality of the coal being received at power stations presently causes severe environmental pollution in and around the plant. This paper deals with the retrofitting of electrostatic precipitators in existing units and the problems encountered in executing the same.

Fast thermal cycling-enhanced electromigration in power metallization

NARCIS (Netherlands)

Nguyen, Van Hieu; Salm, Cora; Krabbenborg, B.H.; Krabbenborg, B.H.; Bisschop, J.; Mouthaan, A.J.; Kuper, F.G.

Fast thermal nterconnects used in power ICs are susceptible to short circuit failure due to a combination of fast thermal cycling and electromigration stresses. In this paper, we present a study of electromigration-induced extrusion short-circuit failure in a standard two level metallization

Availability statistics for thermal power plants

International Nuclear Information System (INIS)

1990-01-01

Denmark, Finland and Sweden have adopted almost the same methods of recording and calculation of availability data. For a number of years comparable availability and outage data for thermal power have been summarized and published in one report. The purpose of the report now presented for 1990 containing general statistical data is to produce basic information on existing kinds of thermal power in the countries concerned. With this information as a basis additional and more detailed information can be exchanged in direct contacts between bodies in the above mentioned countries according to forms established for that purpose. The report includes fossil steam power, nuclear power and gas turbines. The information is presented in separate diagrams for each country, but for plants burning fossil fuel also in a joint NORDEL statistics with data grouped according to type of fuel used. The grouping of units into classes of capacity has been made in accordance with the classification adopted by UNIPEDE/WEC. Values based on energy have been adopted as basic availability data. The same applied to the preference made in the definitions outlined by UNIPEDE and UNIPEDE/WEC. Some data based on time have been included to make possible comparisons with certain international values and for futher illustration of the performance. (au)

New technology and organizational innovation: Niagara Mohawk Power Corporation and nuclear power

International Nuclear Information System (INIS)

Stacey, J.E. Jr.

1981-01-01

Questions with regard to organization behavior and decision theory are explored in relation to the decision-making process of a major private electric utility, Niagara Mohawk Power Corp., that chose to innovate with nuclear power. The character of the firm is such, relative to size, service area, organizational structure, and socio-political environment, that its experience is important for the further development of theories of organizational innovation. The research attempts to understand the political, economic, and social constraints that limited the set of solutions available to the utility in its search for a suitable electricity-generating mode from the early 1950's to the early 1960's. Two contrasting models of organizational decision-making behavior are used to interpret case-study findings. The initial model is from the electric-utility literature and consists essentially of an economic or benefit/cost model of organizational decision making. The second model is developed from the organizational theory literature and is more complex in the sense that factors other than economics such as organizational inertia, the corporate structure of the utility, fuel-supply history and fuel diversification, electricity-demand-growth expectations, the financial environment, and the psychological appeal of the new technology had important influences on Niagara Mohawk's decision to build Nine Mile Point One. Findings of the case study tend to support the second model in that economics was a necessary but not sufficient reason for Niagara Mohawk to have innovated with nuclear power plants

Method of estimating thermal power distribution of core of BWR type reactor

International Nuclear Information System (INIS)

Sekimizu, Koichi

1982-01-01

Purpose: To accurately and rapidly predict the thermal power of the core of a BWR they reactor at load follow-up operating time. Method: A parameter value corrected from a correction coefficient deciding unit and a xenon density distribution value predicted and calculated from a xenon density distributor are inputted to a thermal power distribution predicting devise, the status amount such as coolant flow rate or the like predetermined at this and next high power operating times is substituted for physical model to predict and calculate the thermal power distribution. The status amount of a nuclear reactor at the time of operating in previous high power corresponding to the next high power operation to be predicted is read from the status amount of the reactor stored in time series manner is a reactor core status memory, and the physical model used in the prediction and calculation of the thermal power distribution at the time of next high power operation is corrected. (Sikiya, K.)

Process control and monitoring system: Thermal Power Plant Gacko

International Nuclear Information System (INIS)

Jeremovic, Dragan; Skoko, Maksim; Gjokanovic, Zdravko

2004-01-01

DCS Ovation system, manufactured by Westinghouse, USA, is described in this paper. Emphasize on concept of realization and basic characteristic in Thermal Power Plant Gacko is given in this paper. The most important, noticed by now, comparative effects and performances of new monitoring and control system according to classical monitoring and control system of 300 MW units Thermal Power Plant Gacko in Gacko, are given in the conclusion. (Author)

Thermal hydraulic aspects of uncertainty in power measurement of nuclear reactors

International Nuclear Information System (INIS)

Gupta, S.K.; Kumar, Rajesh; Gaikwad, A.J.; Majumdar, P.; Agrawal, R.A.

2004-01-01

Power measurement in Nuclear Reactors is carried out through in-core and ex-core neutron monitors which are continuously calibrated against thermal power. In Indian Pressurized Heavy Water Reactors (220 MWe) the temperature difference across steam generator hot and cold legs is taken to be a measure of thermal power as the flow through the primary heat transport system is assumed to be constant through out is operation. Gross flow is not measured directly. However, the flow depends on the characteristics of the primary heat transport pumps, which are centrifugal type and are affected by the grid frequency. The paper quantifies the percentage increase in the reactor power for the sustained allowable frequency. The paper quantifies the percentage increase in the reactor power for the sustained allowable high grid frequency. This uncertainty is in addition to instrument inaccuracy and should be accounted for in safety analysis. In some reactors thermal power is calculated from stem flow rate and pressure, here the location of steam flow measurement is important to avoid leakage related error in thermal power. Neutron absorption cross section in the power measurement instruments and the power production in the fuel varies with neutron energy levels, these aspects are also discussed in the paper. (author)

Market: why is thermal solar power down?

International Nuclear Information System (INIS)

Le Jannic, N.

2010-01-01

After a 10 year period of steady growth the French market of the thermal solar power dropped by 15% in 2009. Only 265.000 m 2 were installed instead of 313.000 m 2 in 2008. The main reason of this decrease is the economic crisis: the European market for thermal solar energy dropped by 10%. The second reason is the unfair competition of the photovoltaic power that benefits from very favourable electricity purchase prices, from higher subsidies and from a better image in the public's eye. Another competitor on the market is the new equipment called 'thermodynamic water heater' that involves a heat pump, this equipment is cheaper but only on a short term basis. (A.C.)

The Choice of thermal reactor systems. A report by the National Nuclear Corporation Limited

International Nuclear Information System (INIS)

1977-01-01

The report to the Secretary of State in Great Britain by the National Nuclear Corporation following their assessment of the three thermal reactor systems, the AGR, PWR and SGHWR type reactors, which was performed in order to assist in the decision on the choice of thermal reactors for the U.K., is in three parts. Part I is an assessment of the three systems. It comprises: a description of the general method of assessment; a commentary in which are summarised discussions on the most important issues influencing reactor choice, i.e. safety, component failure, operational characteristics, development programme, construction programme; implications for the U.K. industry; costs; and reference design of each system. Part II consists of related questions and answers accompanied by commentaries on public acceptability and views from industry. Part III contains some conclusions including an analysis on the implications of the choices open and a summary of the main features of the assessment. (U.K.)

Thermoelectron corporation: From space power to Fortune 500

Science.gov (United States)

Scoville, A. Nancy; Masters, Richard

1995-01-01

ThermoElectron Corporation was founded in 1957 to commercialize thermionic energy conversion technologies. Today the company is a Fortune 500 company with 1993 revenues of 1.2 billion. In this paper the methods ThermoElectron used to achieve this result will be discussed with emphasis on the corporate philosophy.

Complete Loss and Thermal Model of Power Semiconductors Including Device Rating Information

DEFF Research Database (Denmark)

Ma, Ke; Bahman, Amir Sajjad; Beczkowski, Szymon

2015-01-01

Thermal loading of power devices are closely related to the reliability performance of the whole converter system. The electrical loading and device rating are both important factors that determine the loss and thermal behaviors of power semiconductor devices. In the existing loss and thermal...

Thermo-economic analysis of Shiraz solar thermal power plant

Energy Technology Data Exchange (ETDEWEB)

Yaghoubi, M. [Academy of Science, Tehran (Iran, Islamic Republic of); Mokhtari, A.; Hesami, R. [Shiraz Univ., Shiraz (Iran, Islamic Republic of). School of Engineering

2007-07-01

The Shiraz solar thermal power plant in Iran has 48 parabolic trough collectors (PTCs) which are used to heat the working oil. There is potential to significantly increase the performance and reduce the cost of PTC solar thermal electric technologies. Conventional energy analysis based on the first law of thermodynamics does qualitatively assess the various losses occurring in the components. Therefore, exergy analysis, based on the second law of thermodynamics, can be applied to better assess various losses quantitatively as well as qualitatively. This paper presented a newly developed exergy-economic model for the Shiraz solar thermal power plant. The objective was to find the minimum exergetic production cost (EPC), based on the second law of thermodynamics. The application of exergy-economic analysis includes the evaluation of utility supply costs for production plants, and the energy costs for process operations. The purpose of the analysis was to minimize the total operating costs of the solar thermal power plant by assuming a fixed rate of electricity production and process steam. 21 refs., 3 tabs., 8 figs.

Theoretical thermodynamic analysis of Rankine power cycle with thermal driven pump

International Nuclear Information System (INIS)

Lakew, Amlaku Abie; Bolland, Olav; Ladam, Yves

2011-01-01

Highlights: → The work is focused on theoretical aspects of thermal driven pump (TDP) Rankine cycle. → The mechanical pump is replaced by thermal driven pump. → Important parameters of thermal driven pump Rankine cycle are investigated. → TDP Rankine cycle produce more power but it requires additional low grade heat. - Abstract: A new approach to improve the performance of supercritical carbon dioxide Rankine cycle which uses low temperature heat source is presented. The mechanical pump in conventional supercritical carbon dioxide Rankine cycle is replaced by thermal driven pump. The concept of thermal driven pump is to increase the pressure of a fluid in a closed container by supplying heat. A low grade heat source is used to increase the pressure of the fluid instead of a mechanical pump, this increase the net power output and avoid the need for mechanical pump which requires regular maintenance and operational cost. The thermal driven pump considered is a shell and tube heat exchanger where the working fluid is contained in the tube, a tube diameter of 5 mm is chosen to reduce the heating time. The net power output of the Rankine cycle with thermal driven pump is compared to that of Rankine cycle with mechanical pump and it is observed that the net power output is higher when low grade thermal energy is used to pressurize the working fluid. The thermal driven pump consumes additional heat at low temperature (60 o C) to pressurize the working fluid.

Maximum thermal loading test of BWR fuel assembly

International Nuclear Information System (INIS)

Nakajima, Yoshitaka; Yoshimura, Kunihiro; Nakamura, Satoshi; Ishizuka, Takao.

1987-01-01

Various proving tests on the reliability of nuclear power plants have been conducted at the Nuclear Power Engineering Test Center and at the Japan Power Plant Engineering and Inspection Corporation. The tests were initiated at the request of the Ministry of International Trade and Industry (MITI). Toshiba undertook one of the proving tests on the reliability of nuclear fuel assembly; the maximum thermal loading test of BWR fuel assembly from the Nuclear Power Engineering Test Center. These tests are part of the proving tests mentioned above, and their purpose is to confirm the reliability of the thermal hydraulic engineering techniques. Toshiba has been engaged for the past nine years in the design, fabrication and testing of the equipment. For the project, a test model fuel assembly was used to measure the critical power of the BWR fuel assembly and the void and fluidity of the coolant. From the test results, it has been confirmed that the heat is transferred safely from the fuel assembly to the coolant in the BWR nuclear power plant. In addition, the propriety and reliability of the thermal hydraulic engineering techniques for the fuel assembly have been proved. (author)

Thermal effects on metabolic activities of thermophilic microorganisms from the thermal discharge point of Tuticorin thermal power plant area

International Nuclear Information System (INIS)

Muthukkannan, N.; Murugesan, A.G.

2002-01-01

Metabolic activities of thermophilic microorganisms isolated from the thermal water discharge point at Tuticorin thermal power station were studied by growing the microorganisms in sterile medium and at various temperature regimes of 25, 35, 45, 55 and 65degC. The optimum temperature for the growth of the bacterium isolated from the thermal power plant station was 45 degC and beyond 65 degC the growth was gradually decreased. The bacteria isolated from open sea water were mesophiles with their growth optimum at 35 degC and microbes inhabiting the thermal discharge area were thermopiles as they were tolerant even at 55 degC. The amylase production, carbohydrate metabolism and lactose fermentation activities were optimum at 45 degC. At 25 degC and beyond 65 degC biochemical activities of the organisms were inhibited to a greater extent. (author)

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.

Thermal loading of wind power converter considering dynamics of wind speed

DEFF Research Database (Denmark)

Baygildina, Elvira; Peltoniemi, Pasi; Pyrhönen, Olli

2013-01-01

The thermal loading of power semiconductors is a crucial performance related to the reliability and cost of the wind power converter. However, the thermal loading impacts by the variation of wind speeds have not yet been clarified, especially when considering the aerodynamic behavior of the wind...... turbines. In this paper, the junction temperatures in the wind power converter are studied under not only steady state, but also turbulent wind speed conditions. The study is based on a 1.5 MW direct-driven turbine system with aerodynamic model described by Unsteady Blade Element Momentum Method (BEMM......), and the thermal stress of power devices is investigated from the frequency spectrum point of view of wind speed. It is concluded that because of the strong inertia effects by the aerodynamic behavior of wind turbines, thermal stress of the semiconductors is relatively more stable and only influenced by the low...

Regulating Corporate Governance in the EU

DEFF Research Database (Denmark)

Horn, Laura

In the context of the financial and economic crisis, corporate governance and regulatory supervision failures are at the centre of public debates. Who controls the modern corporation, and why, has become one of the defining social power relations in contemporary capitalism. Regulation Corporate...... transformation of company law and corporate governance regulation. Her findings about the marketization of corporate control are at the core to a better understanding of the broader context of capitalist restructuring in the European Union....

Cost estimation of thermal and nuclear power using annual securities report

International Nuclear Information System (INIS)

Matsuo, Yuji; Nagatomi, Yu; Murakami, Tomoko

2011-01-01

Cost estimation of generation cost derived from various power sources was widely conducted using model plant or annual securities report of electric utilities. Although annual securities report method was subjected to some limitation in methodology itself, useful information was obtained for cost comparison of thermal and nuclear power. Studies on generation cost evaluation of thermal and nuclear power based on this method during past five years showed that nuclear power cost was almost stable 7 Yen/kWh and thermal power cost was varying 9 - 12 Yen/kWh dependent on violent fluctuations of primary energy cost. Nuclear power was expected cost increase due to enhanced safety requirements or damage compensation of accidents as well as decommissioning and back-end cost, which were difficult to evaluate accurately with annual securities report. Further comprehensive and accurate cost estimation should be encouraged including these items. (T. Tanaka)

Thermal Power Plant Performance Analysis

CERN Document Server

2012-01-01

The analysis of the reliability and availability of power plants is frequently based on simple indexes that do not take into account the criticality of some failures used for availability analysis. This criticality should be evaluated based on concepts of reliability which consider the effect of a component failure on the performance of the entire plant. System reliability analysis tools provide a root-cause analysis leading to the improvement of the plant maintenance plan.   Taking in view that the power plant performance can be evaluated not only based on  thermodynamic related indexes, such as heat-rate, Thermal Power Plant Performance Analysis focuses on the presentation of reliability-based tools used to define performance of complex systems and introduces the basic concepts of reliability, maintainability and risk analysis aiming at their application as tools for power plant performance improvement, including: ·         selection of critical equipment and components, ·         defini...

Cost-effective and reliable design of a solar thermal power plant

International Nuclear Information System (INIS)

Aliabadi, A.A.; Wallace, J.S.

2009-01-01

A design study was conducted to evaluate the cost-effectiveness of solar thermal power generation in a 50 kWe power plant that could be used in a remote location. The system combines a solar collector-thermal storage system utilizing a heat transfer fluid and a simple Rankine cycle power generator utilizing R123 refrigerant. Evacuated tube solar collectors heat mineral oil and supply it to a thermal storage tank. A mineral oil to refrigerant heat exchanger generates superheated refrigerant vapor, which drives a radial turbogenerator. Supplemental natural gas firing maintains a constant thermal storage temperature irregardless of solar conditions enabling the system to produce a constant 50 kWe output. A simulation was carried out to predict the performance of the system in the hottest summer day and the coldest winter day for southern California solar conditions. A rigorous economic analysis was conducted. The system offers advantages over advanced solar thermal power plants by implementing simple fixed evacuated tube collectors, which are less prone to damage in harsh desert environment. Also, backed up by fossil fuel power generation, it is possible to obtain continued operation even during low insolation sky conditions and at night, a feature that stand-alone PV systems do not offer. (author)

Corporate contestability and corporate expropriation

Directory of Open Access Journals (Sweden)

Abdul Hadi Zulkafli

2016-12-01

Full Text Available This paper presents evidence on the role of ownership in dealing with corporate expropriation of listed companies in Malaysia. From the perspective of expropriation, a single controlling shareholder is always associated with such behavior due to their power and control at the expense of minority shareholder. However, subsequent individual or coalition of large shareholders can be an important corporate governance tool by providing effective monitoring that would lessen the possibility of expropriation by the controlling shareholder. Relating to that, this study evaluates the role of controlling and large shareholders in dealing with corporate expropriation. It is found that there is a negative relationship between single controlling shareholders and dividend payout ratio indicating that firms with only controlling shareholder will pay a lower dividend due to possible expropriation through profit diversion by controlling shareholder. Using Herfindahl Index as a proxy for ownership contestability, the presence of large shareholders along with controlling shareholder has a positive relationship with dividend payout implying that increased contestability helps to curb the power of controlling shareholder to expropriate fund for their own benefit. In accordance with agency theory, the outcome suggests that large shareholders play a monitoring role in minimizing the Type II agency problem. It is also verifying the argument made based on the Catering Theory of Dividend that the presence of large shareholder brings benefit to all shareholders as they are able to reduce profit diversion by demanding for higher dividend

Thermal impact assessment of multi power plant operations on estuaries

International Nuclear Information System (INIS)

Eraslan, A.H.; Kim, K.H.; Harris, J.L.

1977-01-01

The assessment of the thermal impact of multi power plant operations on large estuaries requires careful consideration of the problems associated with: re-entrainment, re-circulation, thermal interaction, delay in the attainment of thermal equilibrium state, and uncertainty in specifying open boundaries and open boundary conditions of the regions, which are critically important in the analysis of the thermal conditions in receiving water bodies with tidal dominated, periodically reversing flow conditions. The results of an extensive study in the Hudson River at Indian Point, 42 miles upstream of the ocean end at the Battery, concluded that the tidal-transient, multi-dimensional discrete-element (UTA) thermal transport models (ESTONE, FLOTWO, TMPTWO computer codes) and the near-field far-field zone-matching methodology can be employed with a high degree of reliability in the assessment of the thermal impact of multi power plant operations on tidal dominated estuaries

BUSINESSES WITHOUT BOUNDARIES: A GEOGRAPHY OF CORPORATE POWER

Directory of Open Access Journals (Sweden)

Rozalia Iuliana KICSI

2016-08-01

Full Text Available During the last decades, the literature on international business reflects a growing interest in the extension of the corporate networks and the status of the multinational corporations in the global economy. Firstly, in this study, we briefly summarize several aspects regarding to the strategic focus of the multinational corporations on the global market. Secondly, we intend to map business extension in the international environment from the perspective of regional concentration. In this regard, for each region we have aggregated the key performance indicators (assets, sales and employees which reflect the magnitude of the activities of the companies included by UNCTAD in the Top 100 non-financial TNCs outside the home economic environment. Also, based on the algorithm for calculating the Transnationality Index we estimated an aggregate index for each home region of these companies. The main conclusion drawn from the study is that Europe is the most internationalised region; this tendency is underlined both by the value of the Transnationality Index at regional level and by the total value of the assets hold abroad by the companies which have the home location in the European economic environment. At the same time, from all the developed regions, Europe is the most attractive location for the implantation of the multinational corporations from outside. During the last decades, the literature on international business reflects a growing interest in the extension of the corporate networks and the status of the multinational corporations in the global economy. Firstly, in this study, we briefly summarize several aspects regarding to the strategic focus of the multinational corporations on the global market. Secondly, we intend to map business extension in the international environment from the perspective of regional concentration. In this regard, for each region we have aggregated the key performance indicators (assets, sales and employees which

Solar thermal and concentrated solar power barometer

International Nuclear Information System (INIS)

2013-01-01

The European concentrated solar power plant market is steeling itself for tough time ahead. The number of projects under construction is a pittance compared with 2012 that was an excellent year for installations (an additional 802.5 MW of capacity recorded). This drop is the result of the moratorium on renewable energy power plants introduced by the Spanish government. The European solar thermal market is hardly any more encouraging . EurObserv'ER holds that it slipped for the fourth year in a row (it dropped 5.5% between 2011 and 2012). The newly-installed solar thermal collector surface area in the EU now stands at 3.4 million m 2 , far short of its 2008 installation record of 4.6 million m 2 . The EU's solar thermal base to date at the end of 2012 is 29.6 GWth with 2.4 GWth installed during the year 2012. This article gives tables gathering the figures of the production for every European country for 2012 and describes the market and the general trend for every EU member

Availability Performance Analysis of Thermal Power Plants

Science.gov (United States)

Bhangu, Navneet Singh; Singh, Rupinder; Pahuja, G. L.

2018-03-01

This case study presents the availability evaluation method of thermal power plants for conducting performance analysis in Indian environment. A generic availability model has been proposed for a maintained system (thermal plants) using reliability block diagrams and fault tree analysis. The availability indices have been evaluated under realistic working environment using inclusion exclusion principle. Four year failure database has been used to compute availability for different combinatory of plant capacity, that is, full working state, reduced capacity or failure state. Availability is found to be very less even at full rated capacity (440 MW) which is not acceptable especially in prevailing energy scenario. One of the probable reason for this may be the difference in the age/health of existing thermal power plants which requires special attention of each unit from case to case basis. The maintenance techniques being used are conventional (50 years old) and improper in context of the modern equipment, which further aggravate the problem of low availability. This study highlights procedure for finding critical plants/units/subsystems and helps in deciding preventive maintenance program.

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.

Designing a solar powered Stirling heat engine based on multiple criteria: Maximized thermal efficiency and power

International Nuclear Information System (INIS)

Ahmadi, Mohammad Hossein; Sayyaadi, Hoseyn; Dehghani, Saeed; Hosseinzade, Hadi

2013-01-01

Highlights: • Thermodynamic model of a solar-dish Stirling engine was presented. • Thermal efficiency and output power of the engine were simultaneously maximized. • A final optimal solution was selected using several decision-making methods. • An optimal solution with least deviation from the ideal design was obtained. • Optimal solutions showed high sensitivity against variation of system parameters. - Abstract: A solar-powered high temperature differential Stirling engine was considered for optimization using multiple criteria. A thermal model was developed so that the output power and thermal efficiency of the solar Stirling system with finite rate of heat transfer, regenerative heat loss, conductive thermal bridging loss, finite regeneration process time and imperfect performance of the dish collector could be obtained. The output power and overall thermal efficiency were considered for simultaneous maximization. Multi-objective evolutionary algorithms (MOEAs) based on the NSGA-II algorithm were employed while the solar absorber temperature and the highest and lowest temperatures of the working fluid were considered the decision variables. The Pareto optimal frontier was obtained and a final optimal solution was also selected using various decision-making methods including the fuzzy Bellman–Zadeh, LINMAP and TOPSIS. It was found that multi-objective optimization could yield results with a relatively low deviation from the ideal solution in comparison to the conventional single objective approach. Furthermore, it was shown that, if the weight of thermal efficiency as one of the objective functions is considered to be greater than weight of the power objective, lower absorber temperature and low temperature ratio should be considered in the design of the Stirling engine

Thermal power stations and environmental protection

International Nuclear Information System (INIS)

Gerking, E.

1975-01-01

In this book, the advantages of an optimum cooling concept for waters are compared with the disadvantages of an uncontrolled thermal pollution of waters by waste waters from thermal power plants. The book focuses on the problem of the cost of measures for environmental protection which has not yet received a detailed and complete treatment. The author suggests that perfectionist solutions and superfluos measures be abandoned in favour of a far-reaching, efficient environmental protection concept with a low expenditure of fuel and capital. A detailed treatment is given to false conclusions in the present estimations of the effects of thermal pollution of the waters and to the advantages of freshwater cooling and cooling in general. Also discussed are immission problems and attempts at their solution. (ORU/AK) [de

Decision on thermal power plant can be taken this spring

International Nuclear Information System (INIS)

Haga, I.

1978-01-01

Towards the end of the 1960s it appeared that nuclear power would be the natural successor to hydroelectric power, as the latter became less attractive for further exploitation, reinforced by environmentalist opposition to several proposed hydroelectric schemes. Conventional thermal power was also considered, but one proposed stand-by plant was rejected in 1971 largely because of environmental considerations. Preliminary planning and PR information on nuclear power in the early 1970s aroused considerable opposition and a governmental commission was appointed in 1975-6 to evaluate the question of reactor safety and transport and disposal of radioactive waste, to report in 1978. It is therefore not possible to count on nuclear power as a supplement until the end of the 1980s at the earliest. Gas-fired thermal power is environmentally attractive, but at present no gas fields have been found which make this economic. Oil-fired power is quite feasible, but no political decision has yet been taken. Coal fuel, based on the Spitzbergen mines has recently become more interesting, and small power plants for the extreme north of Norway are under consideration. Finally it is pointed out that nuclear power is safer than generally assumed while fluidised bed combustion of coal in a combined steam-gas turbine plant will lead to very high thermal efficiencies. (JIW)

SSTAC/ARTS review of the draft Integrated Technology Plan (ITP). Volume 3: Space power and thermal management

International Nuclear Information System (INIS)

1991-06-01

Viewgraphs of briefings from the SSTAC/ARTS review of the draft integrated technology plan on thermal power and thermal management are presented. Topics covered include: space energy conversion research and technology; space photovoltaic energy conversion; chemical energy conversion and storage; thermal energy conversion; power management; thermal management; space nuclear power; high capacity power; surface power and thermal management; space platforms power and thermal management; and project SELENE

Direct Estimation of Power Distribution in Reactors for Nuclear Thermal Space Propulsion

Science.gov (United States)

Aldemir, Tunc; Miller, Don W.; Burghelea, Andrei

2004-02-01

A recently proposed constant temperature power sensor (CTPS) has the capability to directly measure the local power deposition rate in nuclear reactor cores proposed for space thermal propulsion. Such a capability reduces the uncertainties in the estimated power peaking factors and hence increases the reliability of the nuclear engine. The CTPS operation is sensitive to the changes in the local thermal conditions. A procedure is described for the automatic on-line calibration of the sensor through estimation of changes in thermal .conditions.

Development of molten carbonate fuel cell technology at M-C Power Corporation

Energy Technology Data Exchange (ETDEWEB)

Dilger, D. [M-C Power Corp., Burr Ridge, IL (United States)

1996-04-01

M-C Power Corporation was founded in 1987 with the mission to further develop and subsequently commercialize molten carbonate fuel cells (MCFC). The technology chosen for commercialization was initially developed by the Institute of Gas technology (IGT). At the center of this MCFC technology is the Internally Manifolded Heat EXchange (IMHEX) separator plate design. The IMHEX technology design provides several functions within one component assembly. These functions include integrating the gas manifold structure into the fuel cell stack, separating the fuel gas stream from the oxidant gas stream, providing the required electrical contact between cells to achieve desired power output, and removing excess heat generated in the electrochemical process. Development of this MCFC technology from lab-scale sizes too a commercial area size of 1m{sup 2} has focused our efforts an demonstrating feasibility and evolutionary progress. The development effort will culminate in a proof-of-concept- 250kW power plant demonstration in 1996. The remainder of our commercialization program focuses upon lowering the costs associated with the MCFC power plant system in low production volumes.

Evaluation of power block arrangements for 100MW scale concentrated solar thermal power generation using top-down design

Science.gov (United States)

Post, Alexander; Beath, Andrew; Sauret, Emilie; Persky, Rodney

2017-06-01

Concentrated solar thermal power generation poses a unique situation for power block selection, in which a capital intensive heat source is subject to daily and seasonal fluctuations in intensity. In this study, a method is developed to easily evaluate the favourability of different power blocks for converting the heat supplied by a concentrated solar thermal plant into power at the 100MWe scale based on several key parameters. The method is then applied to a range of commercially available power cycles that operate over different temperatures and efficiencies, and with differing capital costs, each with performance and economic parameters selected to be typical of their technology type, as reported in literature. Using this method, the power cycle is identified among those examined that is most likely to result in a minimum levelised cost of energy of a solar thermal plant.

Beam-Forming Concentrating Solar Thermal Array Power Systems

Science.gov (United States)

Cwik, Thomas A. (Inventor); Dimotakis, Paul E. (Inventor); Hoppe, Daniel J. (Inventor)

2016-01-01

The present invention relates to concentrating solar-power systems and, more particularly, beam-forming concentrating solar thermal array power systems. A solar thermal array power system is provided, including a plurality of solar concentrators arranged in pods. Each solar concentrator includes a solar collector, one or more beam-forming elements, and one or more beam-steering elements. The solar collector is dimensioned to collect and divert incoming rays of sunlight. The beam-forming elements intercept the diverted rays of sunlight, and are shaped to concentrate the rays of sunlight into a beam. The steering elements are shaped, dimensioned, positioned, and/or oriented to deflect the beam toward a beam output path. The beams from the concentrators are converted to heat at a receiver, and the heat may be temporarily stored or directly used to generate electricity.

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.

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

Congeneration feasibility: Otis Elavator Company and Polychrome Corporation

Science.gov (United States)

Fox, H.

1982-05-01

An investigation of the technical and economic feasibility of cogenerating electric and thermal power at two manufacturing plants (Otis Elevator Company and Polychrome Corporation) located on neighboring properties in Yonkers, NY is discussed. Existing electrical and steam producing equipment and energy consumption date are summarized. Alternative cases examined include electrical energy generation, electrical energy generation with waste heat recovery and a combined cycle case. Also reported are life cycle cost economic evaluations including simple payback period and return on investment indices. While it was concluded that cogeneration of heat and electricity at these industrial plant sites would not be economically viable, this detailed study provides valuable insights.

Thermal effluents from nuclear power plant influences species distribution and thermal tolerance of fishes in reservoirs

International Nuclear Information System (INIS)

Pal, A.K.; Das, T.; Dalvi, R.S.; Bagchi, S.; Manush, S.M.; Ayyappan, S.; Chandrachoodan, P.P.; Apte, S.K.; Ravi, P.M.

2007-01-01

During electricity generation water bodies like reservoir act as a heat sink for thermal effluent discharges from nuclear power plant. We hypothesized that the fish fauna gets distributed according to their temperature preference in the thermal gradient. In a simulated environment using critical thermal methodology (CTM), we assessed thermal tolerance and metabolic profile of fishes (Puntius filamentosus, Parluciosoma daniconius, Ompok malabaricus, Mastacembelus armatus, Labeo calbasu, Horabragrus brachysoma, Etroplus suratensis, Danio aequipinnatus and Gonoproktopterus curmuca) collected from Kadra reservoir in Karnataka state. Results of CTM tests agrees with the species abundance as per the temperature gradient formed in the reservoir due to thermal effluent discharge. E. suratensis and H. brachysoma) appear to be adapted to high temperature (with high CTMax and CTMin values) and are in abundance at point of thermal discharge. Similarly, P. daniconius, appear to be adapted to cold (low CTM values) is in abundance in lower stretches of Kadra reservoir. Overall results indicate that discharge form nuclear power plant influences the species biodiversity in enclosed water bodies. (author)

Thermal pollution impacts on rivers and power supply in the Mississippi River watershed

Science.gov (United States)

Miara, Ariel; Vörösmarty, Charles J.; Macknick, Jordan E.; Tidwell, Vincent C.; Fekete, Balazs; Corsi, Fabio; Newmark, Robin

2018-03-01

Thermal pollution from power plants degrades riverine ecosystems with ramifications beyond the natural environment as it affects power supply. The transport of thermal effluents along river reaches may lead to plant-to-plant interferences by elevating condenser inlet temperatures at downstream locations, which lower thermal efficiencies and trigger regulatory-forced power curtailments. We evaluate thermal pollution impacts on rivers and power supply across 128 plants with once-through cooling technologies in the Mississippi River watershed. By leveraging river network topologies with higher resolutions (0.05°) than previous studies, we reveal the need to address the issue in a more spatially resolved manner, capable of uncovering diverse impacts across individual plants, river reaches and sub-basins. Results show that the use of coarse river network resolutions may lead to substantial overestimations in magnitude and length of impaired river reaches. Overall, there is a modest limitation on power production due to thermal pollution, given existing infrastructure, regulatory and climate conditions. However, tradeoffs between thermal pollution and electricity generation show important implications for the role of alternative cooling technologies and environmental regulation under current and future climates. Recirculating cooling technologies may nearly eliminate thermal pollution and improve power system reliability under stressed climate-water conditions. Regulatory limits also reduce thermal pollution, but at the expense of significant reductions in electricity generation capacity. However, results show several instances when power production capacity rises at individual plants when regulatory limits reduce upstream thermal pollution. These dynamics across energy-water systems highlight the need for high-resolution simulations and the value of coherent planning and optimization across infrastructure with mutual dependencies on natural resources to overcome

Technical and economic aspects of operation of thermal and hydro power systems

Energy Technology Data Exchange (ETDEWEB)

Bakken, Bjoern Harald

1997-12-31

This thesis studies system operation and operational costs of primary and secondary control in hydro and thermal power systems. The cost of providing primary control reserves in thermal power systems is estimated to 1-3% of total production cost. Hydro power units, on the other hand, provide a very cheap primary reserve compared to thermal units. The HVDC (High Voltage Direct Current) connection can be used for primary control in either direction but the thesis only considers substitution of reserves in the thermal system with reserves from the hydro system. Since the HVDC connection is easy to control, the transient characteristics are considerably improved, and one can substitute an amount of thermal spinning reserve corresponding to the available HVDC capacity with little disturbance in any system. A more realistic alternative, at present, is to sell secondary control reserves across the HVDC connections. Keeping spinning reserve for automatic secondary control in a thermal power system is estimated to cost 3-5% of total production cost. Secondary control reserves probably cannot compete with the value of the peak load export, but one should seriously consider using part of the HVDC capacity as secondary control reserve for the thermal system during off-peak hours with. The author discusses the concept of automatic secondary control both theoretically and by simulations and finds that there are no special technical difficulties in introducing automatic secondary control in the Nordel (an organization for Nordic power cooperation) system. 78 refs., 4 figs., 23 tabs.

Technical and economic aspects of operation of thermal and hydro power systems

Energy Technology Data Exchange (ETDEWEB)

Bakken, Bjoern Harald

1998-12-31

This thesis studies system operation and operational costs of primary and secondary control in hydro and thermal power systems. The cost of providing primary control reserves in thermal power systems is estimated to 1-3% of total production cost. Hydro power units, on the other hand, provide a very cheap primary reserve compared to thermal units. The HVDC (High Voltage Direct Current) connection can be used for primary control in either direction but the thesis only considers substitution of reserves in the thermal system with reserves from the hydro system. Since the HVDC connection is easy to control, the transient characteristics are considerably improved, and one can substitute an amount of thermal spinning reserve corresponding to the available HVDC capacity with little disturbance in any system. A more realistic alternative, at present, is to sell secondary control reserves across the HVDC connections. Keeping spinning reserve for automatic secondary control in a thermal power system is estimated to cost 3-5% of total production cost. Secondary control reserves probably cannot compete with the value of the peak load export, but one should seriously consider using part of the HVDC capacity as secondary control reserve for the thermal system during off-peak hours with. The author discusses the concept of automatic secondary control both theoretically and by simulations and finds that there are no special technical difficulties in introducing automatic secondary control in the Nordel (an organization for Nordic power cooperation) system. 78 refs., 4 figs., 23 tabs.

Technical and economic aspects of operation of thermal and hydro power systems

International Nuclear Information System (INIS)

Bakken, Bjoern Harald.

1997-01-01

This thesis studies system operation and operational costs of primary and secondary control in hydro and thermal power systems. The cost of providing primary control reserves in thermal power systems is estimated to 1-3% of total production cost. Hydro power units, on the other hand, provide a very cheap primary reserve compared to thermal units. The HVDC (High Voltage Direct Current) connection can be used for primary control in either direction but the thesis only considers substitution of reserves in the thermal system with reserves from the hydro system. Since the HVDC connection is easy to control, the transient characteristics are considerably improved, and one can substitute an amount of thermal spinning reserve corresponding to the available HVDC capacity with little disturbance in any system. A more realistic alternative, at present, is to sell secondary control reserves across the HVDC connections. Keeping spinning reserve for automatic secondary control in a thermal power system is estimated to cost 3-5% of total production cost. Secondary control reserves probably cannot compete with the value of the peak load export, but one should seriously consider using part of the HVDC capacity as secondary control reserve for the thermal system during off-peak hours with. The author discusses the concept of automatic secondary control both theoretically and by simulations and finds that there are no special technical difficulties in introducing automatic secondary control in the Nordel (an organization for Nordic power cooperation) system. 78 refs., 4 figs., 23 tabs

Application of Thermal Network Model to Transient Thermal Analysis of Power Electronic Package Substrate

Directory of Open Access Journals (Sweden)

Masaru Ishizuka

2011-01-01

Full Text Available In recent years, there is a growing demand to have smaller and lighter electronic circuits which have greater complexity, multifunctionality, and reliability. High-density multichip packaging technology has been used in order to meet these requirements. The higher the density scale is, the larger the power dissipation per unit area becomes. Therefore, in the designing process, it has become very important to carry out the thermal analysis. However, the heat transport model in multichip modules is very complex, and its treatment is tedious and time consuming. This paper describes an application of the thermal network method to the transient thermal analysis of multichip modules and proposes a simple model for the thermal analysis of multichip modules as a preliminary thermal design tool. On the basis of the result of transient thermal analysis, the validity of the thermal network method and the simple thermal analysis model is confirmed.

General 3D Lumped Thermal Model with Various Boundary Conditions for High Power IGBT Modules

DEFF Research Database (Denmark)

Bahman, Amir Sajjad; Ma, Ke; Blaabjerg, Frede

2016-01-01

Accurate thermal dynamics modeling of high power Insulated Gate Bipolar Transistor (IGBT) modules is important information for the reliability analysis and thermal design of power electronic systems. However, the existing thermal models have their limits to correctly predict these complicated...... thermal behaviors in the IGBTs. In this paper, a new three-dimensional (3D) lumped thermal model is proposed, which can easily be characterized from Finite Element Methods (FEM) based simulation and acquire the thermal distribution in critical points. Meanwhile the boundary conditions including...... the cooling system and power losses are modeled in the 3D thermal model, which can be adapted to different real field applications of power electronic converters. The accuracy of the proposed thermal model is verified by experimental results....

Thermal Heat and Power Production with Models for Local and Regional Energy Systems

Energy Technology Data Exchange (ETDEWEB)

Saether, Sturla

1999-07-01

The primary goal of this thesis is the description and modelling of combined heat and power systems as well as analyses of thermal dominated systems related to benefits of power exchange. Large power plants with high power efficiency (natural gas systems) and heat production in local heat pumps can be favourable in areas with low infrastructure of district heating systems. This system is comparable with typical combined heat and power (CHP) systems based on natural gas with respect to efficient use of fuel energy. The power efficiency obtainable from biomass and municipal waste is relatively low and the advantage of CHP for this system is high compared to pure power production with local heat pumps for heat generation. The advantage of converting pure power systems into CHP systems is best for power systems with low power efficiency and heat production at low temperature. CHP systems are divided into two main groups according to the coupling of heat and power production. Some CHP systems, especially those with strong coupling between heat and power production, may profit from having a thermal heat storage subsystem. District heating temperatures direct the heat to power ratio of the CHP units. The use of absorption chillers driven by district heating systems are also evaluated with respect to enhancing the utilisation of district heating in periods of low heat demand. Power exchange between a thermal dominated and hydropower system is found beneficial. Use of hydropower as a substitute for peak power production in thermal dominated systems is advantageous. Return of base load from the thermal dominated system to the hydropower system can balance in the net power exchange.

Assessment of inhalation risk due to radioactivity released from coal-based thermal power plant

International Nuclear Information System (INIS)

Sahu, S.K.; Pandit, G.G.; Shukla, V.K.; Puranik, V.D.; Kushwaha, H.S.

2006-01-01

In India, the coal based thermal power plants have been the major source of power generation in the past and would continue for decades to come. As the coal contains naturally occurring primordial radionuclides the burning of pulverized coal to produce energy for generation of electricity in thermal power plants will result in the emission of a variety of natural radioactive elements into the environment in the vicinity of thermal power plants. In this paper we have used two different methods for characterization of uncertainty in inhalation risk to the general public around 10 Kms radius in the neighborhood of a coal-fired thermal power plant. (author)

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.

Power Control and Monitoring Requirements for Thermal Vacuum/Thermal Balance Testing of the MAP Observatory

Science.gov (United States)

Johnson, Chris; Hinkle, R. Kenneth (Technical Monitor)

2002-01-01

The specific heater control requirements for the thermal vacuum and thermal balance testing of the Microwave Anisotropy Probe (MAP) Observatory at the Goddard Space Flight Center (GSFC) in Greenbelt, Maryland are described. The testing was conducted in the 10m wide x 18.3m high Space Environment Simulator (SES) Thermal Vacuum Facility. The MAP thermal testing required accurate quantification of spacecraft and fixture power levels while minimizing heater electrical emissions. The special requirements of the MAP test necessitated construction of five (5) new heater racks.

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.

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

Using plasma-fuel systems at Eurasian coal-fired thermal power stations

Science.gov (United States)

Karpenko, E. I.; Karpenko, Yu. E.; Messerle, V. E.; Ustimenko, A. B.

2009-06-01

The development of plasma technology for igniting solid fuels at coal-fired thermal power stations in Russia, Kazakhstan, China, and other Eurasian countries is briefly reviewed. Basic layouts and technical and economic characteristics of plasma-fuel systems installed in different coal-fired boiles are considered together with some results from using these systems at coal-fired thermal power stations.

TPDWR2: thermal power determination for Westinghouse reactors, Version 2. User's guide

International Nuclear Information System (INIS)

Kaczynski, G.M.; Woodruff, R.W.

1985-12-01

TPDWR2 is a computer program which was developed to determine the amount of thermal power generated by any Westinghouse nuclear power plant. From system conditions, TPDWR2 calculates enthalpies of water and steam and the power transferred to or from various components in the reactor coolant system and to or from the chemical and volume control system. From these results and assuming that the reactor core is operating at constant power and is at thermal equilibrium, TPDWR2 calculates the thermal power generated by the reactor core. TPDWR2 runs on the IBM PC and XT computers when IBM Personal Computer DOS, Version 2.00 or 2.10, and IBM Personal Computer Basic, Version D2.00 or D2.10, are stored on the same diskette with TPDWR2

Siemens Nuclear Power Corporation experience with BWR and PWR fuels

International Nuclear Information System (INIS)

Reparaz, A.; Smith, M.H.; Stephens, L.G.

1992-01-01

The large data base of fuel performance parameters available to Siemens Nuclear Power Corporation (SNP), and the excellent track record of innovation and fuel reliability accumulated over the last twenty-three years, allows SNP to have a clear insight on the characteristics of future developments in the area of fuel design. Following is a description of some of SNP's recent design innovations to prevent failures and to extend burnup capabilities. A goal paramount to the design and manufacture of BWR and PWR fuel is that of zero defects from any case during its operation in the reactor. Progress has already been made in achieving this goal. This paper summarized the cumulative failure rate of SNP fuel rod through January 1992

Research on Power System Scheduling Improving Wind Power Accommodation Considering Thermal Energy Storage and Flexible Load

Science.gov (United States)

Zou, Chenlu; Cui, Xue; Wang, Heng; Zhou, Bin; Liu, Yang

2018-01-01

In the case of rapid development of wind power and heavy wind curtailment, the study of wind power accommodation of combined heat and power system has become the focus of attention. A two-stage scheduling model contains of wind power, thermal energy storage, CHP unit and flexible load were constructed. This model with the objective function of minimizing wind curtailment and the operation cost of units while taking into account of the total coal consumption of units, constraint of thermal energy storage and electricity-heat characteristic of CHP. This paper uses MICA to solve the problem of too many constraints and make the solution more feasible. A numerical example showed that the two stage decision scheduling model can consume more wind power, and it could provide a reference for combined heat and power system short-term operation

Impact of thermal power generation units on floristic diversity of Kota and its environs

International Nuclear Information System (INIS)

Jain, Shuchita; Dadhich, K.

2001-01-01

The emissions from thermal power plants have great phytotoxic effects on plants due to changes in their morphology and physiology. A floristic study has been conducted near the Thermal Power Station at Kota in Rajasthan to estimate the impact of emissions from the thermal power plant on biota. It is observed that the whole vegetation, especially the perennial trees and shrubs, growing near the station were severely damaged due to effects of air pollutants emitted from the Thermal Power Station. Analysis of the fly ash reveals its composition as composed of silica, alumina, iron oxide etc. (author)

Energy saving and consumption reducing evaluation of thermal power plant

Science.gov (United States)

Tan, Xiu; Han, Miaomiao

2018-03-01

At present, energy saving and consumption reduction require energy saving and consumption reduction measures for thermal power plant, establishing an evaluation system for energy conservation and consumption reduction is instructive for the whole energy saving work of thermal power plant. By analysing the existing evaluation system of energy conservation and consumption reduction, this paper points out that in addition to the technical indicators of power plant, market activities should also be introduced in the evaluation of energy saving and consumption reduction in power plant. Ttherefore, a new evaluation index of energy saving and consumption reduction is set up and the example power plant is calculated in this paper. Rresults show that after introducing the new evaluation index of energy saving and consumption reduction, the energy saving effect of the power plant can be judged more comprehensively, so as to better guide the work of energy saving and consumption reduction in power plant.

The International Finance Corporation and financing of sustainable energy

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-01

The International Finance Corporation (IFC), a member of the World Bank Group, is the largest multilateral source of loan and equity financing for private sector projects in the developing world. IFC participates in an investment only when it can make a special contribution that complements the role of market operators. Since its founding 40 years ago, IFC has provided more than $18.8 billion in financing for 1,706 companies in developing countries. Its share capital is provided by its 170 member countries, which collectively determine its policies and activities. Strong shareholder support and a substantial paid-in capital base have allowed IFC to raise funds for its lending activities through its triple-A rated bond issues in international financial markets. IFC created an Infrastructure Department in 1992 in response to the growing demand for its services in this area. During fiscal 1996 IFC approved 33 projects for new investments of $715 million of which 27% were in the power sector. In recognition of the continuing demand growth for private power investments an expanded Power Department has been formed to handle IFC`s investments in electric power generation projects using renewable resources such as: run-of-the-river hydro, geothermal, biomass cogeneration, wind energy, and solar (photovoltaic, solar thermal, etc.), as well as conventional thermal generation projects, transmission and distribution projects, and energy efficiency investments.

International technologies market for coal thermal power plants

International Nuclear Information System (INIS)

1998-01-01

This paper reports a general framework of potential market of clean coal combustion technologies in thermal power plants, specially for commercialization and market penetration in developing countries [it

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)

BWR 9 X 9 Fuel Assembly Thermal-Hydraulic Tests (2): Hydraulic Vibration Test

International Nuclear Information System (INIS)

Yoshiaki Tsukuda; Katsuichiro Kamimura; Toshiitsu Hattori; Akira Tanabe; Noboru Saito; Masahiko Warashina; Yuji Nishino

2002-01-01

Nuclear Power Engineering Corporation (NUPEC) conducted thermal-hydraulic projects for verification of thermal-hydraulic design reliability for BWR high-burnup 8 x 8 and 9 x 9 fuel assemblies, entrusted by the Ministry of Economy, Trade and Industry (METI). As a part of the NUPEC thermal-hydraulic projects, hydraulic vibration tests using full-scale test assemblies simulating 9 x 9 fuel assemblies were carried out to evaluate BWR fuel integrity. The test data were applied to development of a new correlation for the estimation of fuel rod vibration amplitude. (authors)

Experimental verification of altitude effect over thermal power in an atmospheric burner

International Nuclear Information System (INIS)

Amell Arrieta, Andres; Agudelo, John Ramiro; Cortes, Jaime

1992-01-01

Colombian national massive gasification plan is carried out in a variety of geographic altitudes ranging from 0 to 2.600 meter. The biggest market is located in the Andinan Region, which is characterized by great urban centres located at high altitudes. Commercial, domestic and industrial applications are characterized by the utilization of appliances using atmospheric burners. The thermal power of these burners is affected by altitude. This paper shows experimental results of thermal power reduction in atmospheric burners due to altitude changes. It was found that thermal power is reduced by 1,5% each 304 meters of altitude

Effects of thermal cycling on aluminum metallization of power diodes

DEFF Research Database (Denmark)

Brincker, Mads; Pedersen, Kristian Bonderup; Kristensen, Peter Kjær

2015-01-01

Reconstruction of aluminum metallization on top of power electronic chips is a well-known wear out phenomenon under power cycling conditions. However, the origins of reconstruction are still under discussion. In the current study, a method for carrying out passive thermal cycling of power diodes...

Flexible mechanisms in the corporate greenhouse: implementation of the Kyoto Protocol and the globalization of the electric power industry

Energy Technology Data Exchange (ETDEWEB)

Schreuder, Y.; Sherry, C. [University of Delaware, Newark, DE (United States). Center for Energy and Environmental Policy

2001-07-01

The contradictions and unresolved tensions between economic globalization and climate change negotiations have added urgency to the climate change debate. The paper argues that the declining role of the nation state in the global economy and the increasing reach of transnational corporations throughout the world present a serious challenge to the environmental integrity and success of international environmental treaties such as the Kyoto Protocol. In particular efficacy and equity of the flexible mechanism under the Kyoto Protocol are questioned as illustrated by the patterns of Foreign Direct Investment (FDI) of the US electric power industry in the developing world. US FDI in the electric power sectors of developing countries supports continued carbon-intensive development patterns which will make the long-term goals of the Kyoto Protocol more difficult to achieve. Consequently, FDI raises questions about justifiability of giving credit to Annex I countries through CDM projects undertaken by transnational electric power corporations. 13 refs.

Strategies for emission reduction from thermal power plants.

Science.gov (United States)

Prisyazhniuk, Vitaly A

2006-07-01

Major polluters of man's environment are thermal power stations (TPS) and power plants, which discharge into the atmosphere the basic product of carbon fuel combustion, CO2, which results in a build-up of the greenhouse effect and global warm-up of our planet's climate. This paper is intended to show that the way to attain environmental safety of the TPS and to abide by the decisions of the Kyoto Protocol lies in raising the efficiency of the heat power stations and reducing their fuel consumption by using nonconventional thermal cycles. Certain equations have been derived to define the quantitative interrelationship between the growth of efficiency of the TPS, decrease in fuel consumption and reduction of discharge of dust, fuel combustion gases, and heat into the environment. New ideas and new technological approaches that result in raising the efficiency of the TPS are briefly covered: magneto-hydrodynamic resonance, the Kalina cycle, and utilizing the ambient heat by using, as the working medium, low-boiling substances.

Study on key technologies of optimization of big data for thermal power plant performance

Science.gov (United States)

Mao, Mingyang; Xiao, Hong

2018-06-01

Thermal power generation accounts for 70% of China's power generation, the pollutants accounted for 40% of the same kind of emissions, thermal power efficiency optimization needs to monitor and understand the whole process of coal combustion and pollutant migration, power system performance data show explosive growth trend, The purpose is to study the integration of numerical simulation of big data technology, the development of thermal power plant efficiency data optimization platform and nitrogen oxide emission reduction system for the thermal power plant to improve efficiency, energy saving and emission reduction to provide reliable technical support. The method is big data technology represented by "multi-source heterogeneous data integration", "large data distributed storage" and "high-performance real-time and off-line computing", can greatly enhance the energy consumption capacity of thermal power plants and the level of intelligent decision-making, and then use the data mining algorithm to establish the boiler combustion mathematical model, mining power plant boiler efficiency data, combined with numerical simulation technology to find the boiler combustion and pollutant generation rules and combustion parameters of boiler combustion and pollutant generation Influence. The result is to optimize the boiler combustion parameters, which can achieve energy saving.

Determination of reactor thermal power using a more accurate method

International Nuclear Information System (INIS)

Papuga, J.; Madron, F.; Pliska, J.

2005-01-01

Reactor thermal power is an important operational parameter in many respects such as nuclear safety, reactor physics or evaluation of turbine thermal performance. Thermal power of a pressurized water reactor is determined on the basis of the steam generator thermal balance. The balance can be made in several variants differing from one another by the selection of different measuring circuits whose data are used in the balancing. In principle, no one such variant gives the true value of the thermal power. Among the variant values, the one nearest to the unknown true value of reactor thermal power is probably the value calculated with the lowest uncertainty. The determination of such uncertainty is not easy and its value can make even several percent, which has significant economic consequences. This paper presents the method of data reconciliation and its application to the data of the third of Dukovany NPP. The data reconciliation method allows to exploit all the information which process data contain. It is based on the statistical adjustment of the redundant data in such a way that the adjusted data obey generally valid laws of nature (e.g. conservation laws). Mass and energy balances based on the data not yet reconciled do not obey those laws because of measurement errors. For data reconciliation in Dukovany, a detailed model of mass and energy flows describing the 3rd unit from steam generators to alternator and condenser was set up. Laws of mass and energy conservation and phase equilibrium in water-steam systems are thus fulfilled. Moreover, the user can model momentum balances in pipelines and create other equations, which are respected during calculation. The data reconciliation is done regularly for hourly averages (Authors)

Evaluation of foreign currency payment ability of China Nuclear Power Engineering Corporate

International Nuclear Information System (INIS)

Jiang Zhiqiong; Lu Gang; Zhang Qibo; Wen Suiru; Wu Weiwei

2009-01-01

Through this paper, after making a detailed research into the current foreign currency policy of China and the experience of China Nuclear Power Engineering Corporate(CNPEC) during LA2 project, the author evaluates the current ability of foreign currency settlement ability and defines the applicable process in CNPEC, in order to meet the future needs of CNPEC to make foreign currency payment for the multiple nuclear power projects. To ensure the foreign payment can be settled successfully, CNPEC should pay more attention to the import duty, foreign currency loan, clearing method, remittance after verification, as well as the financial risk management of foreign currency loan. On the premise that CNPEC can also get entitlement of import duty and value added tax preference, the author makes the point about how to enhance the capacity of foreign currency payment of CNPEC. (authors)

Theory "W": The Corporate Warrior.

Science.gov (United States)

Morris, David J., Jr.

1986-01-01

Describes power structure of corporations functioning under Theory W in which single leaders, in partnership with trusted followers, achieve corporate success. Basis of this industrial structure is attributed to social and developmental structures of prehistoric man and city states. Dimensions of W, X, Y, and Z theories are discussed. (MBR)

Challenges in thermal design of industrial single-phase power inverter

Directory of Open Access Journals (Sweden)

Ninković Predrag

2016-01-01

Full Text Available This paper presents the influence of thermal aspects in design process of an industrial single-phase inverter, choice of its topology and components. Stringent design inputs like very high overload level, demand for natural cooling and very wide input voltage range have made conventional circuit topology inappropriate therefore asking for alternative solution. Different power losses calculations in semiconductors are performed and compared, outlining the guidelines how to choose the final topology. Some recommendations in power magnetic components design are given. Based on the final project, a 20kVA single-phase inverter for thermal power plant supervisory and control system is designed and commissioned.

Thermal Management and Reliability of Automotive Power Electronics and Electric Machines

Energy Technology Data Exchange (ETDEWEB)

Narumanchi, Sreekant V [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bennion, Kevin S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cousineau, Justine E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DeVoto, Douglas J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Feng, Xuhui [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kekelia, Bidzina [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kozak, Joseph P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Major, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Moreno, Gilberto [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paret, Paul P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tomerlin, Jeff J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-02-09

Low-cost, high-performance thermal management technologies are helping meet aggressive power density, specific power, cost, and reliability targets for power electronics and electric machines. The National Renewable Energy Laboratory is working closely with numerous industry and research partners to help influence development of components that meet aggressive performance and cost targets through development and characterization of cooling technologies, and thermal characterization and improvements of passive stack materials and interfaces. Thermomechanical reliability and lifetime estimation models are important enablers for industry in cost-and time-effective design.

An estimation of reactor thermal power uncertainty using UFM-based feedwater flow rate in nuclear power plants

International Nuclear Information System (INIS)

Byung Ryul Jung; Ho Cheol Jang; Byung Jin Lee; Se Jin Baik; Woo Hyun Jang

2005-01-01

Most of Pressurized Water Reactors (PWRs) utilize the venturi meters (VMs) to measure the feedwater (FW) flow rate to the steam generator in the calorimetric measurement, which is used in the reactor thermal power (RTP) estimation. However, measurement drifts have been experienced due to some anomalies on the venturi meter (generally called the venturi meter fouling). The VM's fouling tends to increase the measured pressure drop across the meter, which results in indication of increased feedwater flow rate. Finally, the reactor thermal power is overestimated and the actual reactor power is to be reduced to remain within the regulatory limits. To overcome this VM's fouling problem, the Ultrasonic Flow Meter (UFM) has recently been gaining attention in the measurement of the feedwater flow rate. This paper presents the applicability of a UFM based feedwater flow rate in the estimation of reactor thermal power uncertainty. The FW and RTP uncertainties are compared in terms of sensitivities between the VM- and UFM-based feedwater flow rates. Data from typical Optimized Power Reactor 1000 (OPR1000) plants are used to estimate the uncertainty. (authors)

French studies on the thermal effluents of electric power plants

International Nuclear Information System (INIS)

Dezes-Cadiere, H.

1976-01-01

This report presents a synthesis of studies made in France in the thermal effluent field: thermal power plant cooling systems, transfer and dispersion of thermal effluents in the receptive media, effects of thermal effluents on water physicochemistry and biochemistry, effects of thermal effluents on aquatic ecosystems, and, possibilities of waste heat recovery with the view of utilization in agriculture, aquaculture and district heating. A catalogue of French organizations working or having data on thermal effluents is presented, as also an alphabetical list of the contacted persons. A bibliography of French documents concerning the previously mentioned studies is finally given (193 refs.) [fr

Thermodynamic aspects of power production in thermal, chemical and electrochemical systems

International Nuclear Information System (INIS)

Sieniutycz, Stanisław; Poświata, Artur

2012-01-01

We apply optimization methods to study power generation limits for various energy converters, such as thermal, solar, chemical, and electrochemical engines. Methodological similarity is observed when analysing power limits in thermal machines and fuel cells which are electrochemical flow engines. Operative driving forces and voltage are suitable indicators of imperfect phenomena in energy converters. The results obtained generalize our previous findings for power yield limits in purely thermal systems with finite rates. While temperatures T i of participating media were only necessary variables in purely thermal systems, in the present work both temperatures and chemical potentials μ k are essential. This case is associated with engines propelled by fluxes of both energy and substance. In dynamical systems downgrading or upgrading of resources may occur. Energy flux (power) is created in the generator located between the resource fluid (‘upper’ fluid 1) and the environmental fluid (‘lower’ fluid, 2). Fluid properties, transfer mechanisms and conductance values of dissipative layers or conductors influence the rate of power production. Numerical approaches to the dynamical solutions are based on the dynamic programming or maximum principle. Here we focus especially on the latter method, which involves discrete algorithms of Pontryagin’s type. Downgrading or upgrading of resources may also occur in electrochemical systems of fuel cell type. Yet, in this paper we restrict ourselves to the steady-state fuel cells. We present a simple analysis showing that, in linear systems, only at most ¼ of power dissipated in the natural transfer process can be transformed into the noble form of mechanical power.

A Study on infrared tracing and monitoring of thermal discharge from the power plants

Energy Technology Data Exchange (ETDEWEB)

Choi, Byung Sun; Hong, Wuk Hee; Kim, Yung Bae; Park, Jang Rae; Choi, Yung An; Park, Yung San [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1996-08-01

Massive discharge of cooling water from the nuclear power plants as well as many thermal power plants would cause serious environmental problems. Hence, the task of predicting cooling water dispersion areas has enormous importance for better environmental management related with the power plant operation. For the last two decades, extensive field survey and dispersion modeling have been mainly applied to predict thermal discharge dispersion areas. In this study, the method of infrared thermal sensing was tested as a possible means of measuring the affected areas of thermal discharge at the thermal power plant sites. Many IR images obtained by using the terrestrial camera, or by using the airborne scanner, or from the Landsat iv satellite were analyzed from the pc with the IDRISI and resource software and further enhanced with other image analysis technologies. The result of study proved this IR imaging technology to be an potentially cost-effective tool for assessment of water-temperature increase caused by the thermal discharge from the power plants, however, further elaboration of procedure was highly requested. (author). 9 refs., 24 figs.

IS AN INTERNATIONAL CORPORATE HUMAN RIGHTS LIABILITY FRAMEWORK NEEDED? AN ECONOMIC POWER, BUSINESS AND HUMAN RIGHTS, AND AMERICAN EXTRATERRITORIAL JURISDICTION ANALYSIS

Directory of Open Access Journals (Sweden)

Carlos Arevalo

2013-11-01

Full Text Available All companies, regardless of the sector they belong to, can positively or negatively impact human rights. Governments are increasingly aware of the benefits that free trade brings their nations, which has led them to do whatever is necessary to attract foreign investment, even if it means to act against the interests of their own people. The power relationship between corporations and states generates a tension derived from their nature: while the objective of states is the welfare of its members, the purpose of corporations is profit. It is in the crack generated by the collision of powers and purposes between these two actors, that this article is intended to raise the discussion on the need to establish an international framework for corporate liability for human rights violations. To achieve its goal, the article will analyze the opportunities and obstacles raised by the exercise of extraterritorial jurisdiction in the American context and its relationship with the developments in the business and human rights field.

A performance analysis of solar chimney thermal power systems

Directory of Open Access Journals (Sweden)

Al-Dabbas Awwad Mohammed

2011-01-01

Full Text Available The objective of this study was to evaluate the solar chimney performance theoretically (techno-economic. A mathematical model was developed to estimate the following parameter: Power output, Pressure drop across the turbine, the max chimney height, Airflow temperature, and the overall efficiency of solar chimney. The mathematical model was validated with experimental data from the prototype in Manzanares power. It can be concluded that the differential pressure of collector-chimney transition section in the system, is increase with the increase of solar radiation intensity. The specific system costs are between 2000 Eur/kW and 5000 Eur/kW depending on the system size, system concept and storage size. Hence, a 50 MWe solar thermal power plant will cost 100-250 Eur million. At very good sites, today’s solar thermal power plants can generate electricity in the range of 0.15 Eur/kWh, and series production could soon bring down these costs below 0.10 Eur /kWh.

Thermally regenerative hydrogen/oxygen fuel cell power cycles

Science.gov (United States)

Morehouse, J. H.

1986-01-01

Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle, the HTE (high temperature electrolyzer) system, dissociates the water using an electrolyzer operating at high temperature (1300 K) which receives its electrical energy from the fuel cell. The primary advantages of these cycles is that they are basically a no moving parts system, thus having the potential for long life and high reliability, and they have the potential for high thermal efficiency. Both cycles are shown to be classical heat engines with ideal efficiency close to Carnot cycle efficiency. The feasibility of constructing actual cycles is investigated by examining process irreversibilities and device efficiencies for the two types of cycles. The results show that while the processes and devices of the 2000 K TDS exceed current technology limits, the high temperature electrolyzer system appears to be a state-of-the-art technology development. The requirements for very high electrolyzer and fuel cell efficiencies are seen as determining the feasbility of the HTE system, and these high efficiency devices are currently being developed. It is concluded that a proof-of-concept HTE system experiment can and should be conducted.

Environmental protection in thermal power plants

International Nuclear Information System (INIS)

1987-01-01

This workbook is a compilation of the most important facts and data that are relevant today for environmental protection in thermal power plants. Unlike the other issues the text is not in the form of a random collection of data but in the form of a complete presentation. Possible elaboration projects for pupils can be easily derived from the individual sections. These deal with: the discussion about environmental protection; forest decline; sources of emission; nuisances in the Federal Republic of Germany; environmental protection in fossil-fuel power plants - clean air - cooling water utilization and water protection - noise; environmental protection in nuclear power plants - radioactive material produced in nuclear reactors and the retention of such materials - radioactive waste materials - monitoring of radioactive emissions; accessory materials and hints. (orig./HSCH) [de

Air-cooling viability to increase the power in the thermal power stations of gas: Colombian case

International Nuclear Information System (INIS)

Amell, Andres; Bedoya, H. A

2000-01-01

Thermal power decreases as air temperature increases, which reduce both efficiency and projects yielding. Technologically it is possible to eliminate the environment temperature incidence on reduction of power and efficiency, cooling the input air to the turbine, obtaining important power and efficiency improvements. In this work, the technical and economical viability, when applying air cooling technologies (evaporative cooling, steam compression, and production and ice storage (TES) were studied, having in mind meteorological conditions and Colombian electric marketing features, in which, nearly 2800 MW of natural gas thermal power have been installed in the last decade. as a result of applying these cooling technologies the study determined: the mean potential of recoverable power at the second peak of the national demand curve, shows several schemes in which they are technically and economically viable in the Colombian context

Multi-objective superstructure-free synthesis and optimization of thermal power plants

International Nuclear Information System (INIS)

Wang, Ligang; Lampe, Matthias; Voll, Philip; Yang, Yongping; Bardow, André

2016-01-01

The merits of superstructure-free synthesis are demonstrated for bi-objective design of thermal power plants. The design of thermal power plants is complex and thus best solved by optimization. Common optimization methods require specification of a superstructure which becomes a tedious and error-prone task for complex systems. Superstructure specification is avoided by the presented superstructure-free approach, which is shown to successfully solve the design task yielding a high-quality Pareto front of promising structural alternatives. The economic objective function avoids introducing infinite numbers of units (e.g., turbine, reheater and feedwater preheater) as favored by pure thermodynamic optimization. The number of feasible solutions found per number of mutation tries is still high even after many generations but declines after introducing highly-nonlinear cost functions leading to challenging MINLP problems. The identified Pareto-optimal solutions tend to employ more units than found in modern power plants indicating the need for cost functions to reflect current industrial practice. In summary, the multi-objective superstructure-free synthesis framework is a robust approach for very complex problems in the synthesis of thermal power plants. - Highlights: • A generalized multi-objective superstructure-free synthesis framework for thermal power plants is presented. • The superstructure-free synthesis framework is comprehensively evaluated by complex bi-objective synthesis problems. • The proposed framework is effective to explore the structural design space even for complex problems.

Long term energy performance analysis of Egbin thermal power ...

African Journals Online (AJOL)

This study is aimed at providing an energy performance analysis of Egbin thermal power plant. The plant operates on Regenerative Rankine cycle with steam as its working fluid .The model equations were formulated based on some performance parameters used in power plant analysis. The considered criteria were plant ...

Ecological safety of thermal power industry and investments

International Nuclear Information System (INIS)

Glebov, V.P.

1995-01-01

Evaluation of ecological safety of domestic fossil fuel thermal power industry is given in comparison with foreign one. Ways of solving ecological problems are considered. They are based on introduction of new technologies, providing decrease of ecological effect, on development of effective ash-and sulfur-trapping, nitrogen purification equipment, on production of ecologically improved fuel. The necessity of investments to power industry is noted

Conceptual engineering design study of thermionic topping of fossil power plants

Energy Technology Data Exchange (ETDEWEB)

1978-02-15

Primary objectives of this study are to investigate alternative design concepts of thermal coupling of thermionic energy converters (TECs) to the steam cycle and the mechanical and electrical aspects of integrating TEC design into the steam power station. The specific tasks include: (1) evaluate design concepts of TEC topping of solvent refined liquified coal-fired steam power plants, with main emphasis devoted to thermal, mechanical, and electrical design aspects. (2) Develop preliminary conceptual design of a modular TEC assembly. (3) Develop preliminary cost estimates of the design modification to a liquified coal-fired steam power plant with TEC topping. (4) Provide support to Thermo Electron Corporation in planning TEC hardware testing. Results are presented in detail.

Thermal Analysis of a Power Conditioning Unit for a Howitzer

Science.gov (United States)

2009-08-01

contact resistance Interface ( mA2 -K / W) AL-PCB 0.000389 AL-AL (thermal grease) 0.000083 AL-power chips 0.003891 AL-power chips (thermal grease...1120 W/ mA2 . Figure 3 shows the view of the box that the source of the solar radiation sees. The inside of the box is cluttered with cables, wiring, and...temperature (130°F) and a conservative convective heat transfer coefficient (5 W/ mA2 ) to all of the outer surfaces. These outer surfaces would

Fundamental-frequency and load-varying thermal cycles effects on lifetime estimation of DFIG power converter

DEFF Research Database (Denmark)

Zhang, G.; Zhou, D.; Yang, J.

2017-01-01

In respect to a Doubly-Fed Induction Generator (DFIG) system, its corresponding time scale varies from microsecond level of power semiconductor switching to second level of the mechanical response. In order to map annual thermal profile of the power semiconductors, different approaches have been ...... adopted to handle the fundamental-frequency thermal cycles and load-varying thermal cycles. Their effects on lifetime estimation of the power device in the Back-to-Back (BTB) power converter are evaluated.......In respect to a Doubly-Fed Induction Generator (DFIG) system, its corresponding time scale varies from microsecond level of power semiconductor switching to second level of the mechanical response. In order to map annual thermal profile of the power semiconductors, different approaches have been...

Several aspects of the effect of nuclear power engineering and thermal power engineering on the environment

Energy Technology Data Exchange (ETDEWEB)

Malenchenko, A F

1979-01-01

A survey is made of the comparative effect of nuclear power engineering and thermal power engineering on environment and man. The most significant approaches to solution of radio-ecological problems of APS are found.

Method and apparatus for thermal power generation

International Nuclear Information System (INIS)

1981-01-01

A thermal power plant reheat cycle system is described in which the discharge from a first expansion stage is reheated prior to expansion in a subsequent expansion stage. The primary coolant has a high sheet transfer rate and can accommodate temperature changes in the reheat vapor. (U.K.)

The potential estimation and factor analysis of China′s energy conservation on thermal power industry

International Nuclear Information System (INIS)

Lin, Boqiang; Yang, Lisha

2013-01-01

At present, researches about energy conservation are focused on prediction. But there are few researches focused on the estimation of effective input and energy conservation potential, and there has been even no research on energy conservation of thermal power industry of China. This paper will try to fill in such a blank. Panel data on Chinese thermal power industry over 2005–2010 are established, and we adopt the stochastic frontier analysis approach to estimate the energy saving potential of thermal power industry. The results are as follows: (1) the average efficiency of energy inputs in China′s thermal power industry over 2005–2010 was about 0.85, and cumulative energy saving potential equals to 551.04 (Mtce); (2) by improving the non-efficiency factors, the relatively backward inland cities could achieve higher energy saving in thermal power industry; (3) the energy input efficiency of Eastern China Grid is shown to be the highest; (4) in order to realize the energy-saving goal of thermal power industry, one important policy method the government should adopt is to conduct a market-oriented reform in power industry and break the state-owned monopoly to provide incentives for private and foreign direct investment in thermal power sector. -- Highlights: •We adopt SFA model to estimate the coal input efficiency of power sector in China. •We calculate the cumulative energy saving potential equals to 551.04 Mtce. •East China power grid has the highest energy input efficiency. •Some backward inland cities may be the main force for future energy conservation. •Encourage private and foreign direct investment in power sector might be effective

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)

Modeling and Optimization of the Medium-Term Units Commitment of Thermal Power

Directory of Open Access Journals (Sweden)

Shengli Liao

2015-11-01

Full Text Available Coal-fired thermal power plants, which represent the largest proportion of China’s electric power system, are very sluggish in responding to power system load demands. Thus, a reasonable and feasible scheme for the medium-term optimal commitment of thermal units (MOCTU can ensure that the generation process runs smoothly and minimizes the start-up and shut-down times of thermal units. In this paper, based on the real-world and practical demands of power dispatch centers in China, a flexible mathematical model for MOCTU that uses equal utilization hours for the installed capacity of all thermal power plants as the optimization goal and that considers the award hours for MOCTU is developed. MOCTU is a unit commitment (UC problem with characteristics of large-scale, high dimensions and nonlinearity. For optimization, an improved progressive optimality algorithm (IPOA offering the advantages of POA is adopted to overcome the drawback of POA of easily falling into the local optima. In the optimization process, strategies of system operating capacity equalization and single station operating peak combination are introduced to move the target solution from the boundary constraints along the target isopleths into the feasible solution’s interior to guarantee the global optima. The results of a case study consisting of nine thermal power plants with 27 units show that the presented algorithm can obtain an optimal solution and is competent in solving the MOCTU with high efficiency and accuracy as well as that the developed simulation model can be applied to practical engineering needs.

Increasing the efficiency of thermal power stations

International Nuclear Information System (INIS)

Schwarz, N.F.

1984-01-01

High energy prices and an increased investment of costs in power plants as well as the necessity to minimize all kinds of environmental pollution have severe consequences on the construction and operation of thermal power stations. One of the most promising measures to cope with the mentioned problems is to raise the thermal efficiency of power plants. With the example of an Austrian electric utility it can be shown that by application of high efficiency combined cycles primary energy can be converted into electricity in a most efficient manner. Excellent operating experience has proved the high reliability of these relatively complex systems. Raising the temperature of the gas topping process still higher will not raise the efficiency considerably. In this respect a Rankine cycle is superior to a Brayton cycle. In a temperature range of 850 to 900 0 C were conventional materials with known properties can still be used, only the alkali metals cesium and potassium have the necessary physical and thermodynamic properties for application in Rankine topping cycles. Building on experience gained in the Fast Breeder development and from the US space program, a potassium topping cycle linked to a conventional water steam cycle with an intermediate diphenyl vapour cycle has been proposed which should give thermal efficiencies in excess of 50%. In a multi-national program this so called Treble Rankine Cycle is being investigated under the auspices of the International Energy Agency. Work is in progress to investigate the technical and economic feasibility of this energy conversion system. Experimental investigations are already under way in the Austrian Research Center Seibersdorf where high temperature liquid metal test facilities have been operated since 1968. (Author)

Mathematical modelling of thermal-plume interaction at Waterford Nuclear Power Station

International Nuclear Information System (INIS)

Tsai, S.Y.H.

1981-01-01

The Waldrop plume model was used to analyze the mixing and interaction of thermal effluents in the Mississippi River resulting from heated-water discharges from the Waterford Nuclear Power Station Unit 3 and from two nearby fossil-fueled power stations. The computer program of the model was modified and expanded to accommodate the multiple intake and discharge boundary conditions at the Waterford site. Numerical results of thermal-plume temperatures for individual and combined operation of the three power stations were obtained for typical low river flow (200,000 cfs) and maximum station operating conditions. The predicted temperature distributions indicated that the surface jet discharge from Waterford Unit 3 would interact with the thermal plumes produced by the two fossil-fueled stations. The results also showed that heat recirculation between the discharge of an upstream fossil-fueled plant and the intake of Waterford Unit 3 is to be expected. However, the resulting combined temperature distributions were found to be well within the thermal standards established by the state of Louisiana

Behaviour at thermal ageing of power cable components through penetrations

International Nuclear Information System (INIS)

Puiu, D.; Gyongyosi, T.; Dinu, E.

2009-01-01

The materials for electric insulation and exterior jackets of the power cables are formulated organic compounds. The environmental service conditions will induce chemical and/or physical processes at molecular level of the material; these processes are the ageing mechanisms. The power cables passing through penetrations lead to an increase of the rate of thermal ageing mechanisms, resulting in irreversible degradation of mechanical and electric properties of the organic compounds and of the functional properties of the cable. The paper presents the results of the laboratory tests when the real environmental service conditions for penetration are simulated, the comparison with the results of the thermal computation of the power cables heating and the evaluation of the influence of temperature increase of the power cable components on the cable lifetime. For the particular case of a power cable with PVC insulation, we estimated a lifetime decrease about seven years as referred to lifetime of about 30 years for operation in air. (authors)

Technical Feasible Study for Future Solar Thermal Steam Power Station in Malaysia

Science.gov (United States)

Bohari, Z. H.; Atira, N. N.; Jali, M. H.; Sulaima, M. F.; Izzuddin, T. A.; Baharom, M. F.

2017-10-01

This paper proposed renewable energy which is potential to be used in Malaysia in generating electricity to innovate and improve current operating systems. Thermal and water act as the resources to replace limited fossil fuels such as coal which is still widely used in energy production nowadays. Thermal is also known as the heat energy while the water absorbs energy from the thermal to produce steam energy. By combining both of the sources, it is known as thermal steam renewable energy. The targeted area to build this power station has constant high temperature and low humidity which can maximize the efficiency of generating power.

The corporate security professional

DEFF Research Database (Denmark)

Petersen, Karen Lund

2013-01-01

In our age of globalization and complex threat environments, every business is called upon to manage security. This tendency is reflected in the fact that a wide range of businesses increasingly think about security in broad terms and strive to translate national security concerns into corporate...... speech. This article argues that the profession of the security manager has become central for understanding how the relationship between national and corporate security is currently negotiated. The national security background of most private sector security managers makes the corporate security...... professional inside the company a powerful hybrid agent. By zooming in on the profession and the practice of national security inside companies, the article raises questions about where to draw the line between corporate security and national security along with the political consequences of the constitution...

Thermal Storage Power Balancing with Model Predictive Control

DEFF Research Database (Denmark)

Halvgaard, Rasmus; Poulsen, Niels Kjølstad; Madsen, Henrik

2013-01-01

The method described in this paper balances power production and consumption with a large number of thermal loads. Linear controllers are used for the loads to track a temperature set point, while Model Predictive Control (MPC) and model estimation of the load behavior are used for coordination....... The total power consumption of all loads is controlled indirectly through a real-time price. The MPC incorporates forecasts of the power production and disturbances that influence the loads, e.g. time-varying weather forecasts, in order to react ahead of time. A simulation scenario demonstrates...

FGD Franchising Pilot Project of Thermal Power Plants

Institute of Scientific and Technical Information of China (English)

无

2009-01-01

According to the national policy on enhancing environmental protection,the five major power generation companies are required to carry out flue gas desulphurization(FGD) franchising pilot project in thermal power plants.This paper introduces the development of this pilot project,including the foundation,purpose,objects,demands and procedures.It also discusses some main problems encountered during implementation,involving the understanding,legislation,financing,taxation,pricing and management of franchise.At...

About Economy of Fuel at Thermal Power Stations due to Optimization of Utilization Diagram of Power-Generating Equipment

Directory of Open Access Journals (Sweden)

M. V. Svechko

2008-01-01

Full Text Available Problems of rational fuel utilization becomes more and more significant especially for thermal power stations (TPS. Thermal power stations have complicated starting-up diagrams and utilization modes of their technological equipment. Method of diagram optimization of TPS equipment utilization modes has been developed. The method is based on computer analytical model with application of spline-approximation of power equipment characteristics. The method allows to economize fuel consumption at a rate of 15-20 % with accuracy of the predicted calculation not more than 0.25 %.

Estimating the power efficiency of the thermal power plant modernization by using combined-cycle technologies

International Nuclear Information System (INIS)

Hovhannisyan, L.S.; Harutyunyan, N.R.

2013-01-01

The power efficiency of the thermal power plant (TPP) modernization by using combined-cycle technologies is introduced. It is shown that it is possible to achieve the greatest decrease in the specific fuel consumption at modernizing the TPP at the expense of introducing progressive 'know-how' of the electric power generation: for TPP on gas, it is combined-cycle, gas-turbine superstructures of steam-power plants and gas-turbines with heat utilization

Feasibility study on Bobovdol thermal power plant upgrading project

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

A survey has been made in relation with the improvement project intended of energy conservation, and reduction of global warming gas emission at the Bobovdol thermal power plant located in the suburb of Sofia, the capital of the Republic of Bulgaria. The existing Bobovdol power plant having a total capacity of 630 MW with three generators is a coal burning thermal power plant having been used already for 23 to 27 years, hence over-aged. The survey has discussed an improvement project of scrap-and-build type to make the plant a high-efficiency gas combined cycle power plant using gas turbines. The project calls for building 210-MW gas combined power generation facilities having 70-MW gas turbines, one each in three stages in 2007, 2012 and 2017. As a result of the discussions, the fuel consumption reducing rate was found to reach 37.99%, whereas the cumulative energy saving quantity in 41 years will reach 16.37 million tons of fuel oil equivalent. In addition, the reduction rate of global warming gas emission is 57.75%, and the cumulative reduction quantity in 41 years is 105.18 million tons. (NEDO)

Adaptation of thermal power plants: The (ir)relevance of climate (change) information

International Nuclear Information System (INIS)

Bogmans, Christian W.J.; Dijkema, Gerard P.J.; Vliet, Michelle T.H. van

2017-01-01

When does climate change information lead to adaptation? We analyze thermal power plant adaptation by means of investing in water-saving (cooling) technology to prevent a decrease in plant efficiency and load reduction. A comprehensive power plant investment model, forced with downscaled climate and hydrological projections, is then numerically solved to analyze the adaptation decisions of a selection of real power plants. We find that operators that base their decisions on current climatic conditions are likely to make identical choices and perform just as well as operators that are fully ‘informed’ about climate change. Where electricity supply is mainly generated by thermal power plants, heat waves, droughts and low river flow may impact electricity supply for decades to come. - Highlights: • We analyze adaptation to climate change by thermal power plants. • A numerical investment model is applied to a coal plant and a nuclear power plant. • The numerical analysis is based on climate and hydrological projections. • Climate change information has a relatively small effect on a power plant's NPV. • Uncertainty and no-regret benefits lower the value of climate change information.

An Optimization Scheduling Model for Wind Power and Thermal Power with Energy Storage System considering Carbon Emission Trading

Directory of Open Access Journals (Sweden)

Huan-huan Li

2015-01-01

Full Text Available Wind power has the characteristics of randomness and intermittence, which influences power system safety and stable operation. To alleviate the effect of wind power grid connection and improve power system’s wind power consumptive capability, this paper took emission trading and energy storage system into consideration and built an optimization model for thermal-wind power system and energy storage systems collaborative scheduling. A simulation based on 10 thermal units and wind farms with 2800 MW installed capacity verified the correctness of the models put forward by this paper. According to the simulation results, the introduction of carbon emission trading can improve wind power consumptive capability and cut down the average coal consumption per unit of power. The introduction of energy storage system can smooth wind power output curve and suppress power fluctuations. The optimization effects achieve the best when both of carbon emission trading and energy storage system work at the same time.

Using thermal power plants waste for building materials

Science.gov (United States)

Feduik, R. S.; Smoliakov, A. K.; Timokhin, R. A.; Batarshin, V. O.; Yevdokimova, Yu G.

2017-10-01

The recycled use of thermal power plants (TPPs) wastes in the building materials production is formulated. The possibility of using of TPPs fly ash as part of the cement composite binder for concrete is assessed. The results of X-ray diffraction and differential thermal analysis as well as and materials photomicrographs are presented. It was revealed that the fly ash of TPPs of Russian Primorsky Krai is suitable for use as a filler in cement binding based on its chemical composition.

Control of thermal therapies with moving power deposition field

International Nuclear Information System (INIS)

Arora, Dhiraj; Minor, Mark A; Skliar, Mikhail; Roemer, Robert B

2006-01-01

A thermal therapy feedback control approach to control thermal dose using a moving power deposition field is developed and evaluated using simulations. A normal tissue safety objective is incorporated in the controller design by imposing constraints on temperature elevations at selected normal tissue locations. The proposed control technique consists of two stages. The first stage uses a model-based sliding mode controller that dynamically generates an 'ideal' power deposition profile which is generally unrealizable with available heating modalities. Subsequently, in order to approximately realize this spatially distributed idealized power deposition, a constrained quadratic optimizer is implemented to compute intensities and dwell times for a set of pre-selected power deposition fields created by a scanned focused transducer. The dwell times for various power deposition profiles are dynamically generated online as opposed to the commonly employed a priori-decided heating strategies. Dynamic intensity and trajectory generation safeguards the treatment outcome against modelling uncertainties and unknown disturbances. The controller is designed to enforce simultaneous activation of multiple normal tissue temperature constraints by rapidly switching between various power deposition profiles. The hypothesis behind the controller design is that the simultaneous activation of multiple constraints substantially reduces treatment time without compromising normal tissue safety. The controller performance and robustness with respect to parameter uncertainties is evaluated using simulations. The results demonstrate that the proposed controller can successfully deliver the desired thermal dose to the target while maintaining the temperatures at the user-specified normal tissue locations at or below the maximum allowable values. Although demonstrated for the case of a scanned focused ultrasound transducer, the developed approach can be extended to other heating modalities with

Market Power in Hydro-Thermal Supply

International Nuclear Information System (INIS)

Edin, Karl-Axel

2006-12-01

Despite having had a deregulated electricity market in Sweden for over ten years we still need to increase our understanding as to how deregulated electricity markets actually work and how possible problems are to be solved. One question that is always in focus is if the competition between generators in the Nordic electricity market really works the way it was intended. Many argue that the concentration in ownership of generation plants already has gone too far. Together with joint ownership in nuclear facilities and barriers for entrance, critics say that this has resulted in higher electricity prices than necessary. In this report different methods to (ex ante) study potential possibilities for generating firms to influence the electricity price (market power) and (ex post) discover possible manipulation through analysing the spot price and other observed factors on the electricity market are analysed. The purpose of the longer underlying paper is to give a comprehensive treatment of the electricity market with storage, i.e. hydro power, with an auction market organisation and to test the models on the Nordic market in order to explore the explanatory power of auction market theory and the theory of contestable market. The main theoretical effort in the paper concerns auction theory with inventories. The paper develops an inter-temporal auction model of a thermal-hydro power market. Parallel to the derivation of the basic equations a numerical model is developed in order to illustrate the results of the model. Section 2 of the present paper summarizes the basic equations (derived in the longer paper) for an inter-temporal auction thermal-hydro market. Section 3 contains the illustrations of solutions to equations for some stylized markets. In section 4 the auction model is tested on the Nordic market

Low-Cost Radiator for Fission Power Thermal Control

Science.gov (United States)

Maxwell, Taylor; Tarau, Calin; Anderson, William; Hartenstine, John; Stern, Theodore; Walmsley, Nicholas; Briggs, Maxwell

2014-01-01

NASA Glenn Research Center (GRC) is developing fission power system technology for future Lunar surface power applications. The systems are envisioned in the 10 to 100kW(sub e) range and have an anticipated design life of 8 to 15 years with no maintenance. NASA GRC is currently setting up a 55 kW(sub e) non-nuclear system ground test in thermal-vacuum to validate technologies required to transfer reactor heat, convert the heat into electricity, reject waste heat, process the electrical output, and demonstrate overall system performance. Reducing the radiator mass, size, and cost is essential to the success of the program. To meet these goals, Advanced Cooling Technologies, Inc. (ACT) and Vanguard Space Technologies, Inc. (VST) are developing a single facesheet radiator with heat pipes directly bonded to the facesheet. The facesheet material is a graphite fiber reinforced composite (GFRC) and the heat pipes are titanium/water. By directly bonding a single facesheet to the heat pipes, several heavy and expensive components can be eliminated from the traditional radiator design such as, POC(TradeMark) foam saddles, aluminum honeycomb, and a second facesheet. A two-heat pipe radiator prototype, based on the single facesheet direct-bond concept, was fabricated and tested to verify the ability of the direct-bond joint to withstand coefficient of thermal expansion (CTE) induced stresses during thermal cycling. The thermal gradients along the bonds were measured before and after thermal cycle tests to determine if the performance degraded. Overall, the results indicated that the initial uniformity of the adhesive was poor along one of the heat pipes. However, both direct bond joints showed no measureable amount of degradation after being thermally cycled at both moderate and aggressive conditions.

Thermal analysis of two-level wind power converter under symmetrical grid fault

DEFF Research Database (Denmark)

Zhou, Dao; Blaabjerg, Frede

2013-01-01

In this paper, the case of symmetrical grid fault when using the multi-MW wind turbine of partial-scale and full-scale two-level power converter are designed and investigated. Firstly, the different operation behaviors of the relevant power converters under the voltage dip will be described......) condition as well as the junction temperature. For the full-scale wind turbine system, the most thermal stressed power device in the grid-side converter will appear at the grid voltage below 0.5 pu, and for the partial-scale wind turbine system, the most thermal stressed power device in the rotor...

Thermal effects in high average power optical parametric amplifiers.

Science.gov (United States)

Rothhardt, Jan; Demmler, Stefan; Hädrich, Steffen; Peschel, Thomas; Limpert, Jens; Tünnermann, Andreas

2013-03-01

Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given.

Techno-economic design optimization of solar thermal power plants

OpenAIRE

Morin, G.

2011-01-01

A holistic view is essential in the engineering of technical systems. This thesis presents an integrative approach for designing solar thermal power plants. The methodology is based on a techno-economic plant model and a powerful optimization algorithm. Typically, contemporary design methods treat technical and economic parameters and sub-systems separately, making it difficult or even impossible to realize the full optimization potential of power plant systems. The approach presented here ov...

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)

Exergetic comparison of two different cooling technologies for the power cycle of a thermal power plant

International Nuclear Information System (INIS)

Blanco-Marigorta, Ana M.; Victoria Sanchez-Henriquez, M.; Pena-Quintana, Juan A.

2011-01-01

Exergetic analysis is without any doubt a powerful tool for developing, evaluating and improving an energy conversion system. In the present paper, two different cooling technologies for the power cycle of a 50 MWe solar thermal power plant are compared from the exergetic viewpoint. The Rankine cycle design is a conventional, single reheat design with five closed and one open extraction feedwater heaters. The software package GateCycle is used for the thermodynamic simulation of the Rankine cycle model. The first design configuration uses a cooling tower while the second configuration uses an air cooled condenser. With this exergy analysis we identify the location, magnitude and the sources or thermodynamic inefficiencies in this thermal system. This information is very useful for improving the overall efficiency of the power system and for comparing the performance of both technologies.

Siemens Nuclear Power Corporation methods development for BWR/PWR reactor licensing

International Nuclear Information System (INIS)

Pruitt, D.W.

1992-01-01

This presentation addresses the Siemens Nuclear Power Corporation (SNP) perspective on the primary forces driving methods development in the nuclear industry. These forces are fuel design, computational environment and industry requirement evolution. The first segment of the discussion presents the SNP experience base. SNP develops, manufactures and licenses both BWR and PWR reload fuel. A review of this experience base highlights the accelerating rate at which new fuel designs are being introduced into the nuclear industry. The application of advanced BWR lattice geometries provides an example of fuel design trends. The second aspect of the presentation is the rapid evolution of the computing environment. The final subject in the presentation is the impact of industry requirements on code or methods development

Thermal pollution of the atmosphere, in particular due to power plant parks

International Nuclear Information System (INIS)

Fortak, H.

1977-01-01

In the paper, a diagram is set up and described which relates the influence of power plant agglomerations to natural atmospheric phenomena, energetically and in some ways also dynamically. As there are no power plant agglomeration in existence at present, there is neither empirical knowledge on the meteorological and climatological effects to be expected from such agglomerations, nor are empirically proved theoretical predictions of the effects possible. In the diagram, the specific vertical energy flow is given for the thermal power emitted and the emission are for natural and anthropogenic thermal sources, and characteristic values are calculated for the thermal lift and the vertical velocity at representative heights above the area. As far as the arrangement of cooling towers is concerned, it is found that it is better to avoid cooling tower agglomerations on small areas and to erect smaller power stations distributed over a large area instead. (orig.) [de

High-power electronics thermal management with intermittent multijet sprays

International Nuclear Information System (INIS)

Panão, Miguel R.O.; Correia, André M.; Moreira, António L.N.

2012-01-01

Thermal management plays a crucial role in the development of high-power electronics devices, e.g. in electric vehicles. The greatest energy demands occur during power peaks, implying dynamic thermal losses within the vehicle’s driving cycle. Therefore, the need for devising intelligent thermal management systems able to efficiently respond to these power peaks has become a technological challenge. Experiments have been performed with methanol in order to quantify the maximum heat flux removed by a multijet spray to keep the 4 cm 2 surface temperature stabilized and below the threshold of 125 °C. A multijet atomization strategy consists in producing a spray through the multiple and simultaneous impact of N j cylindrical jets. Moreover, the spray intermittency is expressed through the duty cycle (DC), which depends on the frequency and duration of injection. Results evidence that: i) a shorter time between consecutive injection cycles enables a better distribution of the mass flow rate, resulting in larger heat transfer coefficient values, as well as higher cooling efficiencies; ii) compared with continuous sprays, the analysis evidences that an intermittent spray allows benefiting more from phase-change convection. Moreover, the mass flux is mainly affecting heat transfer rather than differences induced in the spray structure by using different multijet configurations. - Highlights: ► Intermittent spray cooling (ISC) is advantageous for intelligent thermal management. ► Distributing the mass flow rate through ISC improves heat transfer. ► Multijet sprays with increasing number of jets have higher heat transfer rates. ► ISC with multijet sprays benefit more from phase-change than continuous sprays.

Deregulation of the California electric power industry: An analysis of electric and natural gas corporate mergers and their effect on the California electric power market

Science.gov (United States)

Hornbuckle, James Dixon

Deregulation of the electric utility industry in California is moving in a direction that places greater reliance on the market forces of competition. Investor owned utilities (IOU's) are using mergers and acquisitions to improve their ability to compete in this new environment. Two large mergers were proposed in 1996 that could affect the California market. The first is between Enron Corporation, a large power marketer and Portland General Corporation, owner of Portland General Electric. The second is between Pacific Enterprises Inc., owner of Southern California Gas Company, the largest natural gas utility in the U. S., and Enova Corporation, owner of San Diego Gas and Electric Company. Understanding the impact of these mergers on the California electric power market is the focus of this study. This study examines hypotheses dealing with: (1) Merger Strategy, (2) Efficiency, and (3) Market Power. Using the Miles and Snow (1978) typology, I develop a strategic orientation model for the merger participants and their competitors. The results suggest a two-stage strategic orientation: (1) regulated core business stage, where the firms follow a Defender strategy, and (2) unregulated business stage, where the firms follow a Prospector strategy. Further, the results show the mergers are consistent with the strategy of Enron and Pacific Enterprises. Event study methodology, dollar gains/losses and market value weighted returns are used to determine if the mergers support the efficiency hypothesis. The evidence suggests the mergers lead to increased competitive advantage through improved efficiency for the participants. The results also suggest the mergers do not harm the rivals. The results of structural changes made by the California Public Utilities Commission (CPUC) in deregulation of the California market and analysis of the mergers by the CPUC and the Public Utility Commission of Oregon suggest that the exercise of market power is not a significant issue. Finally

77 FR 3585 - Airworthiness Directives; Cirrus Design Corporation Airplanes

Science.gov (United States)

2012-01-25

... Airworthiness Directives; Cirrus Design Corporation Airplanes AGENCY: Federal Aviation Administration (FAA), DOT... Corporation (Cirrus) Model SR22T airplanes. This AD was prompted by reports of partial loss of engine power.... ADDRESSES: For service information identified in this AD, contact Cirrus Design Corporation, 4515 Taylor...

Thermal-wave balancing flow sensor with low-drift power feedback

NARCIS (Netherlands)

Dijkstra, Marcel; Lammerink, Theodorus S.J.; Pjetri, O.; de Boer, Meint J.; Berenschot, Johan W.; Wiegerink, Remco J.; Elwenspoek, Michael Curt

2014-01-01

A control system using a low-drift power-feedback signal was implemented applying thermal waves, giving a sensor output independent of resistance drift and thermo-electric offset voltages on interface wires. Kelvin-contact sensing and power control is used on heater resistors, thereby inhibiting the

Computer systems for thermal power plant operation and management; Karyoku hatsudensho no kodo joho system

Energy Technology Data Exchange (ETDEWEB)

Adachi, M.; Miyabe, K.; Matsumoto, A. [Toshiba Corp., Tokyo (Japan)

1997-07-01

To improve on work efficiency by pooling information and prompting the transmission of information at thermal power stations, efforts have been under way for some years to realize a working environment in which everyone is provided with a computer exclusively for one`s own use. Toshiba Corporation believes that the coming information system has to be equipped with two features of on-demand and EUC (end user computing). Introduced in this report are some approaches to systems that will take care of plant operation information and facility information making use of Toshiba`s advanced information system GS7000XP series. Plant operation information is categorized into process data, operation history data, checking patrol data, and periodic inspection data and, for instance, a distributed-type management computer provided with data recording and application processing servers is used for handling operation history data. For the collection of facility information, efforts are being made to establish a computer network step by step for exchanging information with manufacturers and associated businesses. 3 refs., 4 figs., 1 tab.

Compliance management and corporate governance; Compliance Management und Corporate Governance

Energy Technology Data Exchange (ETDEWEB)

Becker, Uwe [Stadt Frankfurt am Main (Germany); Alsheimer, Constantin; Kassebohm, Kristian; Reutler, Susanne [Mainova AG, Frankfurt (Germany)

2009-08-15

Starting in the year 2009, numerous changes in the financial system and accountancy a well as in the corporate law come into effect for enterprises. Thereby, the requirements substantially are intensified to their corporate governance. The actual well-known reproaches of bribery, corruption and injuries of data protection intensify the pressure on executive committees and supervisory boards in order to meet normative and ethical requirements. All the more is valid for power suppliers whose reputation can already carry damage out with the first suspicion. Already in 2008, Mainova AG (Frnkfurt/Main, Federal Republic of Germany) implemented a compliance management.

Powers and Duties of the Corporate Affairs Commission as a ...

African Journals Online (AJOL)

The Corporate Affairs Commission was established by section 1 of the Companies and Allied Matters Act, Cap C.20, Laws of the Federation of Nigeria, 2004 (CAMA). The Corporate Affairs Commission is a regulatory body, established to regulate the incorporation, running and winding up of companies, business names and ...

Modelling and Improvement of Thermal Cycling in Power Electronics for Motor Drive Applications

DEFF Research Database (Denmark)

Vernica, Ionut; Ma, Ke; Blaabjerg, Frede

2016-01-01

It is well known that the dynamical change of the thermal stress in the power devices is one of the major factors that have influences on the overall efficiency and reliability of power electronics. The main objective of this paper consists of identifying the main parameters that affect the thermal...... are identified during the acceleration and deceleration periods of the motor. The main causes for these adverse thermal cycles have been presented and, consequently, the influence of the deceleration slope, modulation technique and reactive current on the thermal cycles has been analyzed. Finally, the improved...

Small Spacecraft Integrated Power System with Active Thermal Control

Data.gov (United States)

National Aeronautics and Space Administration — This project will develop an integrated power generation and energy storage system with an active thermal management system. Carbon fiber solar panels will contain...

Method and apparatus for thermal power generation

International Nuclear Information System (INIS)

Mangus, J.D.

1979-01-01

A method is described for power generation from a recirculating superheat-reheat circuit with multiple expansion stages which alleviates complex control systems and minimizes thermal cycling of system components, particularly the reheater. The invention includes preheating cold reheat fluid from the first expansion stage prior to its entering the reheater with fluid from the evaporator or drum component

Experimental investigation of a PCM-HP heat sink on its thermal performance and anti-thermal-shock capacity for high-power LEDs

International Nuclear Information System (INIS)

Wu, Yuxuan; Tang, Yong; Li, Zongtao; Ding, Xinrui; Yuan, Wei; Zhao, Xuezhi; Yu, Binhai

2016-01-01

Highlights: • A phase-change material (PCM) base heat pipe heat sink (PCM-HP heat sink) is designed. • The PCM-HP heat sink can significantly lower the LED heating rate and temperature. • The PCM-HP heat sink achieves a best anti-thermal-shock capacity in LED cyclic working modes. - Abstract: High-power LEDs demonstrate a number of benefits compared with conventional incandescent lamps and fluorescent lamps, including a longer lifetime, higher brightness and lower power consumption. However, owing to their severe high heat flux, it is difficult to develop effective thermal management of high-power LEDs, especially under cyclic working modes, which cause serious periodic thermal stress and limit further development. Focusing on the above problem, this paper designed a phase-change material (PCM) base heat pipe heat sink (PCM-HP heat sink) that consists of a PCM base, adapter plate, heat pipe and finned radiator. Different parameters, such as three types of interior materials to fill the heat sink, three LED power inputs and eight LED cyclic working modes, were separately studied to investigate the thermal performance and anti-thermal-shock capacity of the PCM-HP heat sink. The results show that the PCM-HP heat sink possesses remarkable thermal performance owing to the reduction of the LED heating rate and peak temperature. More importantly, an excellent anti-thermal-shock capacity of the PCM-HP heat sink is also demonstrated when applied in LED cyclic working modes, and this capacity demonstrates the best range.

Potential impact of thermal effluents from Chongqing Fuling nuclear power plant to the Three Gorges Reservoir

International Nuclear Information System (INIS)

Han Baohua; Li Jianguo; Ma Binghui; Zhang Yue; Sun Qunli; Hu Yuping

2012-01-01

This study is based on the hydrological data near Chongqing Fuling Nuclear Power Plant along the Yangtze River, the present situation of the ecological environment of the Three Gorges Reservoir and the predicted results of thermal effluents from Chongqing Fuling Nuclear Power Plant. The standards of cooling water and the thermal tolerances indexes of aquatic organisms were investigated. The effects of thermal effluents on aquatic organisms were analyzed. The potential impact of Chongqing Fuling nuclear power plant to the Three Gorges Reservoir was explained. The results show that in the most adverse working conditions, the surface temperature near the outfall area is not more than 1℃, the temperature of thermal effluents do not exceed the suitable thermal range of fish breeding, growth and other thermal tolerances indexes. Thermal effluents from nuclear power plant have no influence about fish, plankton and benthic organisms in the Three Gorges Reservoir. (authors)

Modelling of Power Fluxes during Thermal Quenches

International Nuclear Information System (INIS)

Konz, C.; Coster, D. P.; Lackner, K.; Pautasso, G.

2005-01-01

Plasma disruptions, i. e. the sudden loss of magnetic confinement, are unavoidable, at least occasionally, in present day and future tokamaks. The expected energy fluxes to the plasma facing components (PFCs) during disruptions in ITER lie in the range of tens of GW/m''2 for timescales of about a millisecond. Since high energy fluxes can cause severe damage to the PFCs, their design heavily depends on the spatial and temporal distribution of the energy fluxes during disruptions. We investigate the nature of power fluxes during the thermal quench phase of disruptions by means of numerical simulations with the B2 SOLPS fluid code. Based on an ASDEX Upgrade shot, steady-state pre-disruption equilibria are generated which are then subjected to a simulated thermal quench by artificially enhancing the perpendicular transport in the ion and electron channels. The enhanced transport coefficients flows the Rechester and Rosenbluth model (1978) for ergodic transport in a tokamak with destroyed flux surfaces, i. e. χ, D∼const. xT''5/2 where the constants differ by the square root of the mass ratio for ions and electrons. By varying the steady-state neutral puffing rate we can modify the divertor conditions in terms of plasma temperature and density. Our numerical findings indicate that the disruption characteristics depend on the pre disruptive divertor conditions. We study the timescales and the spatial distribution of the divertor power fluxes. The simulated disruptions show rise and decay timescales in the range observed at ASDEX Upgrade. The decay timescale for the central electron temperature of ∼800 μs is typical for non-ITB disruptions. Varying the divertor conditions we find a distinct transition from a regime with symmetric power fluxes to inboard and outboard divertors to a regime where the bulk of the power flux goes to the outboard divertor. This asymmetry in the divertor peak fluxes for the higher puffing case is accompanied by a time delay between the

A thermally regenerative ammonia-based battery for efficient harvesting of low-grade thermal energy as electrical power

KAUST Repository

Zhang, Fang

2015-01-01

© 2015 The Royal Society of Chemistry. Thermal energy was shown to be efficiently converted into electrical power in a thermally regenerative ammonia-based battery (TRAB) using copper-based redox couples [Cu(NH3)4 2+/Cu and Cu(ii)/Cu]. Ammonia addition to the anolyte (2 M ammonia in a copper-nitrate electrolyte) of a single TRAB cell produced a maximum power density of 115 ± 1 W m-2 (based on projected area of a single copper mesh electrode), with an energy density of 453 W h m-3 (normalized to the total electrolyte volume, under maximum power production conditions). Adding a second cell doubled both the voltage and maximum power. Increasing the anolyte ammonia concentration to 3 M further improved the maximum power density to 136 ± 3 W m-2. Volatilization of ammonia from the spent anolyte by heating (simulating distillation), and re-addition of this ammonia to the spent catholyte chamber with subsequent operation of this chamber as the anode (to regenerate copper on the other electrode), produced a maximum power density of 60 ± 3 W m-2, with an average discharge energy efficiency of ∼29% (electrical energy captured versus chemical energy in the starting solutions). Power was restored to 126 ± 5 W m-2 through acid addition to the regenerated catholyte to decrease pH and dissolve Cu(OH)2 precipitates, suggesting that an inexpensive acid or a waste acid could be used to improve performance. These results demonstrated that TRABs using ammonia-based electrolytes and inexpensive copper electrodes can provide a practical method for efficient conversion of low-grade thermal energy into electricity.

The State of the Corporation

DEFF Research Database (Denmark)

Hein Jessen, Mathias

Today it has become commonplace to claim the demise of the power of the democratic nation-state due to globalization, neoliberal policies and the increasing power of transnational entities (UN, EU, IMF, WTO, World Bank) and multinational corporations. This view, however, prevalent in both public...

Nuclear Groups - World. Market Analysis - 2016-2019 Trends - Corporate Strategies

International Nuclear Information System (INIS)

2016-03-01

This study presents: The medium-term and mega trends of the industry market developments and geographical segments; The competitive landscape and the main corporate rankings; The main conclusions of the report, summarised in 10 analytical slides. Content: 1. Market Fundamentals: Overview, The Industry; 2. Market Environment and Prospects: Market Overview, Macroeconomic Environment, Supply, Demand, Industry Structure, Energy costs and prices, Market Prospects, Regional Overview; 3. Corporate Strategies and Competition: Competitive Environment, Corporate Strategies and Competition, Structure of Competition, Corporate Strategies; 4. Case Studies; 5. Company Profiles: Toshiba, KEPCO, Mitsubishi Heavy Industries, Areva, GE-Hitachi Nuclear Energy, Cameco, Urenco, Engie, EDF, Rosatom, China National Nuclear Power, KazAtomProm, China General Nuclear Power Corporation; 6. Statistical Appendix; 7. Sources; 8. Annexes

Output power analyses for the thermodynamic cycles of thermal power plants

International Nuclear Information System (INIS)

Sun Chen; Cheng Xue-Tao; Liang Xin-Gang

2014-01-01

Thermal power plant is one of the important thermodynamic devices, which is very common in all kinds of power generation systems. In this paper, we use a new concept, entransy loss, as well as exergy destruction, to analyze the single reheating Rankine cycle unit and the single stage steam extraction regenerative Rankine cycle unit in power plants. This is the first time that the concept of entransy loss is applied to the analysis of the power plant Rankine cycles with reheating and steam extraction regeneration. In order to obtain the maximum output power, the operating conditions under variant vapor mass flow rates are optimized numerically, as well as the combustion temperatures and the off-design flow rates of the flue gas. The relationship between the output power and the exergy destruction rate and that between the output power and the entransy loss rate are discussed. It is found that both the minimum exergy destruction rate and the maximum entransy loss rate lead to the maximum output power when the combustion temperature and heat capacity flow rate of the flue gas are prescribed. Unlike the minimum exergy destruction rate, the maximum entransy loss rate is related to the maximum output power when the highest temperature and heat capacity flow rate of the flue gas are not prescribed. (general)

Loss and thermal model for power semiconductors including device rating information

DEFF Research Database (Denmark)

Ma, Ke; Bahman, Amir Sajjad; Beczkowski, Szymon

2014-01-01

The electrical loading and device rating are both important factors that determine the loss and thermal behaviors of power semiconductor devices. In the existing loss and thermal models, only the electrical loadings are focused and treated as design variables, while the device rating is normally...

Thermal Loading and Lifetime Estimation for Power Device Considering Mission Profiles in Wind Power Converter

DEFF Research Database (Denmark)

Ma, Ke; Liserre, Marco; Blaabjerg, Frede

2015-01-01

for the reliability improvement and also for cost reduction of wind power technology. Unfortunately, the existing lifetime estimation methods for the power electronic converter are not yet suitable in the wind power application, because the comprehensive mission profiles are not well specified and included......As a key component in the wind turbine system, the power electronic converter and its power semiconductors suffer from complicated power loadings related to environment, and are proven to have high failure rates. Therefore, correct lifetime estimation of wind power converter is crucial...... devices, more detailed information of the lifetime-related performance in wind power converter can be obtained. Some experimental results are also included to validate the thermal behavior of power device under different mission profiles....

A Hybrid Power Control Concept for PV Inverters with Reduced Thermal Loading

DEFF Research Database (Denmark)

Yang, Yongheng; Wang, Huai; Blaabjerg, Frede

2014-01-01

on a single-phase PV inverter under yearly operation is presented with analyses of the thermal loading, lifetime, and annual energy yield. It has revealed the trade-off factors to select the power limit and also verified the feasibility and the effectiveness of the proposed control concept.......This letter proposes a hybrid power control concept for grid-connected Photovoltaic (PV) inverters. The control strategy is based on either a Maximum Power Point Tracking (MPPT) control or a Constant Power Generation (CPG) control depending on the instantaneous available power from the PV panels....... The essence of the proposed concept lies in the selection of an appropriate power limit for the CPG control to achieve an improved thermal performance and an increased utilization factor of PV inverters,and thus to cater for a higher penetration level of PV systems with intermittent nature. A case study...

Reactive power influence on the thermal cycling of multi-MW wind power inverter

DEFF Research Database (Denmark)

Ma, Ke; Liserre, Marco; Blaabjerg, Frede

2012-01-01

converter system are first presented at different wind speeds. Furthermore, the interaction between paralleled converter systems in a wind park is also considered and analyzed. By controlling the reactive power circulated among paralleled converters, a new concept is then proposed to stabilize the thermal...

Thermal design, analysis and comparison on three concepts of space solar power satellite

Science.gov (United States)

Yang, Chen; Hou, Xinbin; Wang, Li

2017-08-01

Space solar power satellites (SSPS) have been widely studied as systems for collecting solar energy in space and transmitting it wirelessly to earth. A previously designed planar SSPS concept collects solar power in two huge arrays and then transmits it through one side of the power-conduction joint to the antenna. However, the system's one group of power-conduction joints may induce a single point of failure. As an SSPS concept, the module symmetrical concentrator (MSC) architecture has many advantages. This architecture can help avoid the need for a large, potentially failure-prone conductive rotating joint and limit wiring mass. However, the thermal control system has severely restricted the rapid development of MSC, especially in the sandwich module. Because of the synchronous existence of five suns concentration and solar external heat flux, the sandwich module will have a very high temperature, which will surpass the permissible temperature of the solar cells. Recently, an alternate multi-rotary joints (MR) SSPS concept was designed by the China Academy of Space Technology (CAST). This system has multiple joints to avoid the problem of a single point of failure. Meanwhile, this concept has another advantage for reducing the high power and heat removal in joints. It is well known to us that, because of the huge external flux in SSPS, the thermal management sub-system is an important component that cannot be neglected. Based on the three SSPS concepts, this study investigated the thermal design and analysis of a 1-km, gigawatt-level transmitting antenna in SSPS. This study compares the thermal management sub-systems of power-conduction joints in planar and MR SSPS. Moreover, the study considers three classic thermal control architectures of the MSC's sandwich module: tile, step, and separation. The study also presents an elaborate parameter design, analysis and discussion of step architecture. Finally, the results show the thermal characteristics of each SSPS

Prospect and problems of gas based power stations of NTPC

International Nuclear Information System (INIS)

Suryanarayana, A.

1993-01-01

The policy of the Government of India concerning utilisation of natural gas resources of the country has undergone changes over the last few years. The government decided in 1985 to allocate natural gas for power generation and in the year 1986 approved the setting up of the first series of three gas based combined cycle power projects of National Thermal Power Corporation (NTPC). The problems of gas power stations of NTPC are discussed. These are high cost of generation, completion of transmission line works to match with the commissioning of gas power stations, high price of natural gas, and fixation of tariff for sale of power from gas based power stations. (N.B.)

Heat engine development for solar thermal power systems

Science.gov (United States)

Pham, H. Q.; Jaffe, L. D.

The parabolic dish solar collector systems for converting sunlight to electrical power through a heat engine will, require a small heat engine of high performance long lifetime to be competitive with conventional power systems. The most promising engine candidates are Stirling, high temperature Brayton, and combined cycle. Engines available in the current market today do not meet these requirements. The development of Stirling and high temperature Brayton for automotive applications was studied which utilizes much of the technology developed in this automotive program for solar power engines. The technical status of the engine candidates is reviewed and the components that may additional development to meet solar thermal system requirements are identified.

Effect of increased renewables generation on operation of thermal power plants

International Nuclear Information System (INIS)

Eser, Patrick; Singh, Antriksh; Chokani, Ndaona; Abhari, Reza S.

2016-01-01

Highlights: • Impacts of increased renewables in central European transmission system are assessed. • Individual transmission lines and power plants of transmission system are modelled. • Starts and ramps of thermal power plants significantly increase with increased renewables. • Impact of renewables on thermal power plants is highly dependent on location. - Abstract: High spatial and temporal resolution optimal power flow simulations of the 2013 and 2020 interconnected grid in Central Western and Eastern Europe regions are undertaken to assess the impact of an increased penetration of renewables on thermal power plants. In contrast to prior studies, the present work models each individual transmission line and power plant within the two regions. Furthermore, for conventional plants, electricity costs are determined with respect to fuel type, nameplate capacity, operating condition and geographic location; cycling costs are modeled as function of the recent operational history. For renewable power plants, costs and available power are determined using mesoscale weather simulations and hydrology models. Countrywide validation of the simulations shows that all renewable and most conventional power production is predicted with less than 10% error. It is shown that the increased penetration of renewables in 2020 will induce a 4–23% increase in the number of starts of conventional plants. The number of load ramps significantly increases by 63–181%, which underlines the necessity for equipment manufacturers and utilities to adapt to scenarios of high penetration of renewables. The increased cycling operation of coal plants is shown to depend strongly on the power plant’s location and is mainly observed in Germany and the Czech Republic. Austrian coal plants are cycled less because they supply more base load power to southern Germany, where several nuclear power plants will be phased out by 2020. Thus there is a need for more transmission capacity along

Corporate Branding and Corporate Reputation

DEFF Research Database (Denmark)

Karmark, Esben

2013-01-01

Corporate branding has been seen as developing in “waves”. This chapter explores the links between corporate branding and corporate reputation as they emerge in the context of three waves of corporate branding. It highlights the way in which the two constructs have related to each other through o...... for corporate brands and corporate communication.......Corporate branding has been seen as developing in “waves”. This chapter explores the links between corporate branding and corporate reputation as they emerge in the context of three waves of corporate branding. It highlights the way in which the two constructs have related to each other through...... organizational culture and identity, and how, although characterized by parallel developments, new ideas and models from a “third” wave of corporate branding challenge prevailing assumptions of corporate reputation particularly in terms of the assumptions that reputations emerge from authentic and transparent...

Thermal pollution of rivers and reservoirs by discharges of heated water from thermal and nuclear power plants

International Nuclear Information System (INIS)

Makarov, I.

1974-12-01

The problems are discussed of the thermal pollution of rivers and water reservoirs by discharges of heated water from thermal and nuclear power plants. The problems concerned are quantitative and qualitative changes in biocenoses, the disturbance or extinction of flora and fauna, physiological changes in organisms and changes in the hydrochemical regime. (Z.M.)

The accident prevention regulation 'Thermal Power Stations' and its effects in practice

International Nuclear Information System (INIS)

Albert, O.

1983-01-01

The origin of the accident prevention regulation - ''Thermal Power Stations'' is attributable mainly to two tragic accidents. It has made organizational changes and interventions in the operational process necessary in thermal power stations. Emphasis is laid upon the consistent issue of written permits-to-work on plant components carrying a heating medium and operating under pressure and on written operating licences for the operation of boilers. The paper describes additional ways in which regulation influences the daily practices of the power station operator. Brief references is made to the draft of the revised regulation. (orig./HP) [de

energy and exergy evaluation of a 220mw thermal power plant

African Journals Online (AJOL)

HOD

The outcomes of this work provide the exergy consumption and distribution profiles of the thermal power plant ... power plant with post-combustion CO2 capture. The once-through boiler exhibited the highest exergy destruction of all the plants ...

Availability of thermal power plants 1977-1986

International Nuclear Information System (INIS)

Nitsch, D.; Schmitz, H.

1987-01-01

To get a picture of power plant availability and its influencing factors, availability data have been acquired and evaluated by VGB according to different design and operation parameters since 1970. The present volume is the 16th annual statistics since 1970. It covers the decade of 1977 to 1986 and contains availability data of 384 power plants in Germany and abroad, with a total of 94.896 MW and 3.768 plant years. Data are presented on fossil-fuelled units, units with a combined gas/steam cycle, nuclear power plants and gas turbine systems, with further sub-categories according to unit size, fuel, type, years of operation, and operating regime. German plants are reviewed separately. All power data are gross data measured at the generator terminals. For a comparative evaluation, the data of 1986 are supplemented by yearly averages since 1977 and averages for the decade from 1977 to 1986. Since 1978, nonavailability data are categorized as 'unscheduled' and 'scheduled' nonavailabilities. For availability data of 1970 to 1976, see the VGB publication 'Availability of thermal power plants, 1970 to 1981'. (orig./UA) [de

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.

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.

Availability of thermal power plants 1976-1985

International Nuclear Information System (INIS)

Nitsch, D.; Schmitz, H.

1986-01-01

This assessment is the 15th annual assessment since 1970. It covers the decade 1976 to 1985 and contains the availability figures for 395 power stations in Germany and abroad with an output of about 93,750 MW and 3,642 years of power station operation. The availability figures of fossil fired units, combined units (plant with combined gas/steam circuit), nuclear power stations and gas turbine plants are given, which are classified according to unit size, fuel, type of construction, age and method of use. The German plants are covered separately. All output figures are gross figures (output at the generator terminals). For comparison purposes, apart for the results of 1985, the annual values determined since 1976 and the mean values for the decade 1976-1985 are given. The non-availability is divided into faults and planned outages since 1978. Availability figures for the years 1970 to 1975 can be found in the VGB assessment 'Availability of thermal power plants 1970-1981'. (orig./GL) [de

Thermal power plants and acid rain

International Nuclear Information System (INIS)

Ataman, Eleonora

1990-01-01

The slow acidification of the environment and the frequent occurrence of the precipitation with pH lower than 5.6 over areas continuously extending are caused by the pollutant releases, especially SO 2 and NO x from anthropic sources. There is a relationship between the SO 2 release from the high stacks of thermal power plants and the long-range transfrontier pollution. The most efficient method to avoid damage on environment is to reduce the releases from stationary and mobile sources. (author)

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

Limits to solar power conversion efficiency with applications to quantum and thermal systems

Science.gov (United States)

Byvik, C. E.; Buoncristiani, A. M.; Smith, B. T.

1983-01-01

An analytical framework is presented that permits examination of the limit to the efficiency of various solar power conversion devices. Thermodynamic limits to solar power efficiency are determined for both quantum and thermal systems, and the results are applied to a variety of devices currently considered for use in space systems. The power conversion efficiency for single-threshold energy quantum systems receiving unconcentrated air mass zero solar radiation is limited to 31 percent. This limit applies to photovoltaic cells directly converting solar radiation, or indirectly, as in the case of a thermophotovoltaic system. Photoelectrochemical cells rely on an additional chemical reaction at the semiconductor-electrolyte interface, which introduces additional second-law demands and a reduction of the solar conversion efficiency. Photochemical systems exhibit even lower possible efficiencies because of their relatively narrow absorption bands. Solar-powered thermal engines in contact with an ambient reservoir at 300 K and operating at maximum power have a peak conversion efficiency of 64 percent, and this occurs for a thermal reservoir at a temperature of 2900 K. The power conversion efficiency of a solar-powered liquid metal magnetohydrodydnamic generator, a solar-powered steam turbine electric generator, and an alkali metal thermoelectric converter is discussed.

'Crud' detection and evaluation during the Embalse nuclear power plant's thermal cycle for powers of 100%

International Nuclear Information System (INIS)

Fernandez, A.; Rosales, A.H.; Mura, V.R.; Sentupery, C.; Rascon, H.

1987-01-01

This paper describes the 'crud' measurements performed during the Embalse nuclear power plant's thermal cycle for a power of 100% (645 MWe) under different purification conditions. The aim of this work is to optimize the four steam generators' tube plate cleaning in function of the sweeping produced by their purification. (Author)

Cost Analysis of an Air Brayton Receiver for a Solar Thermal Electric Power System in Selected Annual Production Volumes

Science.gov (United States)

1981-01-01

Pioneer Engineering and Manufacturing Company estimated the cost of manufacturing and Air Brayton Receiver for a Solar Thermal Electric Power System as designed by the AiResearch Division of the Garrett Corporation. Production costs were estimated at annual volumes of 100; 1,000; 5,000; 10,000; 50,000; 100,000 and 1,000,000 units. These costs included direct labor, direct material and manufacturing burden. A make or buy analysis was made of each part of each volume. At high volumes special fabrication concepts were used to reduce operation cycle times. All costs were estimated at an assumed 100% plant capacity. Economic feasibility determined the level of production at which special concepts were to be introduced. Estimated costs were based on the economics of the last half of 1980. Tooling and capital equipment costs were estimated for ach volume. Infrastructure and personnel requirements were also estimated.

Thermal power plant operating regimes in future British power systems with increasing variable renewable penetration

International Nuclear Information System (INIS)

Edmunds, Ray; Davies, Lloyd; Deane, Paul; Pourkashanian, Mohamed

2015-01-01

Highlights: • This work investigates thermal power operating regimes in future power systems. • Gas plants have low utilisation in the scenarios considered. • Ramping intensity increases for gas plants and pumped storage. • Coal plants frequently operate at minimum stable levels and start-ups increase. • Grid emission intensity and total emission production remains substantial. - Abstract: This work investigates the operational requirements of thermal power plants in a number of potential future British power systems with increasing variable renewable penetration. The PLEXOS Integrated Energy Model has been used to develop the market models, with PLEXOS employing mixed integer programming to solve the unit commitment and economic dispatch problem, subject to a number of constraints. Initially, a model of the British power system was developed and validated. Subsequently, a 2020 test model was developed to analyse a number of future system structures with differing fuel and carbon prices and generation mixes. The study has found that in three of the four scenarios considered, the utilisation of gas power plants will be relatively low, but remains fundamental to the security of supply. Also, gas plants will be subject to more intense ramping. The findings have consequent implications for energy policy as expensive government interventions may be required to prevent early decommissioning of gas capacity, should the prevailing market conditions not guarantee revenue adequacy.

Congeneration feasibility: Otis Elevator Company and Polychrome Corporation. Final report

Energy Technology Data Exchange (ETDEWEB)

Fox, H.

1982-05-01

This report summarizes an investigation of the technical and economic feasibility of cogenerating electric and thermal power at two manufacturing plants (Otis Elevator Company and Polychrome Corporation) located on neighboring properties in Yonkers, NY. Existing electrical- and steam-producing equipment and energy consumption date are summarized. Alternative cases examined include electrical energy generation, electrical energy generation with waste heat recovery and a combined cycle case. Also reported are life cycle cost economic evaluations including simple payback period and return-on-investment indices. While it was concluded that cogeneration of heat and electricity at these industrial plant sites would not be economically viable, this detailed study provides valuable insight into the types of problems encountered when considering cogeneration feasibility.

Corporate Citizenship and Stakeholder Engagement : Maintaining an Equitable Power Balance

OpenAIRE

Ihugba, Bethel Uzoma; Osuji, Onyeka K.

2011-01-01

This paper proposes an engagement oriented corporation-stakeholder relationship in Corporate Social Responsibility (CSR) programmes. It is a proposition which poses the two connected questions of how to move from solely public relation driven stakeholder management to social development oriented stakeholder participation (engagement) and how Stakeholder Engagement can be measured. On the backdrop of Arnstein’s (1969) citizenship participation model and reasons for Stakeholder Engagement frame...

Power cables thermal protection by interval simulation of imprecise dynamical systems

Energy Technology Data Exchange (ETDEWEB)

Bontempi, G. [Universite Libre de Brussels (Belgium). Dept. d' Informatique; Vaccaro, A.; Villacci, D. [Universita del Sannio Benevento (Italy). Dept. of Engineering

2004-11-01

The embedding of advanced simulation techniques in power cables enables improved thermal protection because of higher accuracy, adaptiveness and. flexibility. In particular, they make possible (i) the accurate solution of differential equations describing the cables thermal dynamics and (ii) the adoption of the resulting solution in the accomplishment of dedicated protective functions. However, the use of model-based protective systems is exposed to the uncertainty affecting some model components (e.g. weather along the line route, thermophysical properties of the soil, cable parameters). When uncertainty can be described in terms of probability distribution, well-known techniques, such as Monte Carlo, are used to simulate the system behaviour. On the other hand, when the description of uncertainty in probabilistic terms is unfeasible or problematic, nonprobabilistic alternatives should be taken into consideration. This paper will discuss and compare three interval-based techniques as alternatives to probabilistic methods in the simulation of power cable dynamics. The experimental session will assess the interval-based approaches by simulating the thermal behaviour of medium voltage power cables.(author)

Analysis of the Opportunity for an Increase in the Thermal Power of Power Generating Units of Nuclear Power Plants (Part 1)

OpenAIRE

Chernousenko, Olga Yuriivna; Nikulenkova, Tetiana Volodymyrivna; Nikulenkov, Anatolii Hennadiiovych

2017-01-01

For Ukraine the realization of available reserves to increase the power of operating power units of nuclear plants is a vital problem the solution of which would allow us to increase electric power output. A special role is also played by economic priorities; in particular an increase in power by 1 kW is ten times cheaper in comparison with the construction of 1 kW of new power facilities. One more factor is the world experience in the field of an increase in the thermal power of operating po...

Alternative trends in development of thermal power plants

International Nuclear Information System (INIS)

Prisyazhniuk, Vitaly A.

2008-01-01

Thermal (or fossil fuel) power plants (TPP) are the major polluters of man's environment, discharging into the atmosphere the basic product of carbon fuel combustion, CO 2 . It is this very gas that accounts for the greenhouse effect causing the global climate warm-up on our planet. A natural solution of the problem of reducing carbon dioxide discharge into the atmosphere lies in power saving, thus reducing the amount of the fuel burnt. This approach can be justified from any standpoint, both economically and ecologically. The ideal way of solving the problem would be to completely give up burning carbon-containing fuel, such as coal, petroleum products, and other power resources of organic nature. This work is intended to outline the ways of reducing consumption of fuel by TPP and, consequently, of reducing their discharging into the atmosphere the gases producing the greenhouse effect. One of the ways lies in changing the thermophysical characteristics of the working medium, which becomes possible if we can modify the conventional working medium, that is water, or can use some working medium with quite different thermophysical properties. The article dwells on various technological ways providing for a practical solution of the problem, such as the Kalina cycle; modification of water properties by way of magneto-hydrodynamic resonance (MHD resonance); and employing, in the thermodynamic cycle of Thermal Power Plants, liquids boiling at temperatures which are lower than that of the environment

The THESEUS project -- 50 MWe solar thermal power for Crete

Energy Technology Data Exchange (ETDEWEB)

Schillig, F.; Geyer, M.; Kistner, R.; Aringhoff, R.; Nava, P.; Brakmann, G.

1998-07-01

A consortium of European industry, utilities and research institutions from Greece, Germany, Spain and Italy attempts to implement a 52 MWe solar thermal power plant with parabolic trough technology on the Greek island of Crete sponsored by the EU' s THERMIE program. The increased demand for electricity on the island, a consequence of the growing allurement of the island as a tourist resort, makes it necessary to expand the installed capacity on Crete during the next years. According to the capacity expansion plans of Greek' s utility PPC a 160 MWe heavy fuel-fired power plant complex--two 30 MWe diesel units and two 50 MWe steam turbine units--is foreseen to be built by the year 2002. In this paper a description of the technical, economical and environmental aspects of the THESEUS project is provided. Moreover a market entry strategy for solar thermal power generation is discussed.

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.

Examination of applicability of thermoelectric power measurement for thermal aging evaluation of cast duplex stainless steel to real components in nuclear power plants

International Nuclear Information System (INIS)

Joubouji, Katsuo

2006-01-01

It is known the mechanical properties of cast duplex stainless steel, which is used for main coolant pipes of pressurized water reactor type nuclear power plants, change due to thermal aging. Non-destructive evaluation method for thermal aging using thermoelectric power measurement has been studied in INSS. And it has been found that there was some relation between mechanical properties and thermoelectric power in the case of accelerated aging sample and change in thermoelectric power was caused by change in microstructure due to thermal aging. In this study, n-site measurement of thermoelectric power of a main coolant pipe with the measurement device which has been used in a laboratory was carried out. As a result, thermoelectric power of the main coolant pipe was almost measured within the range from -2.2 to -2μ V/degC, and that was corresponding to the relation of accelerated aging samples between thermoelectric power and the product of ferrite content and aging parameter considering the standard error. Moreover, applying the measured thermoelectric power to the relation of accelerated aging samples between thermoelectric power and impact value, change in the impact value of the pipe seemed to be corresponding to about 40% of the maximum change assumed by thermal aging. (author)

Thermal stability improvement of a multiple finger power SiGe heterojunction bipolar transistor under different power dissipations using non-uniform finger spacing

International Nuclear Information System (INIS)

Chen Liang; Zhang Wan-Rong; Jin Dong-Yue; Shen Pei; Xie Hong-Yun; Ding Chun-Bao; Xiao Ying; Sun Bo-Tao; Wang Ren-Qing

2011-01-01

A method of non-uniform finger spacing is proposed to enhance thermal stability of a multiple finger power SiGe heterojunction bipolar transistor under different power dissipations. Temperature distribution on the emitter fingers of a multi-finger SiGe heterojunction bipolar transistor is studied using a numerical electro-thermal model. The results show that the SiGe heterojunction bipolar transistor with non-uniform finger spacing has a small temperature difference between fingers compared with a traditional uniform finger spacing heterojunction bipolar transistor at the same power dissipation. What is most important is that the ability to improve temperature non-uniformity is not weakened as power dissipation increases. So the method of non-uniform finger spacing is very effective in enhancing the thermal stability and the power handing capability of power device. Experimental results verify our conclusions. (interdisciplinary physics and related areas of science and technology)

Cost structure analysis of commercial nuclear power plants in Japan based on corporate financial statements of electric utility companies

International Nuclear Information System (INIS)

Kunitake, Norifumi; Nagano, Koji; Suzuki, Tatsujiro

1998-01-01

In this paper, we analyze past and current cost structure of commercial nuclear power plants in Japan based on annual corporate financial statements published by the Japanese electric utility companies, instead of employing the conventional methodology of evaluating the generation cost for a newly constructed model plant. The result of our study on existing commercial nuclear plants reveals the increasing significance of O and M and fuel cycle costs in total generation cost. Thus, it is suggested that electric power companies should take more efforts to reduce these costs in order to maintain the competitiveness of nuclear power in Japan. (author)

Trend analysis of troubles caused by thermal-hydraulic phenomena at nuclear power plants

International Nuclear Information System (INIS)

Komatsu, Teruo

2010-01-01

The Institute of Nuclear Safety System (INSS) is promoting researches to improve the safety and reliability of nuclear power plants. In the present study, our attention was focused on troubles attributed to thermal-hydraulic phenomena in particular, trend analysis were carried out to learn lessons from these troubles and to prevent their recurrence. Through our survey, we found the following two points. First, many thermal-hydraulics related troubles can be attributed to design faults, since we found some events in foreign countries took place after inadequate facility renovation. To ensure appropriate design verification, it is important to take account of state-of-the-art science and technology and at the same time to pay attention to the compatibility with the initial design concept. Second point, thermal-hydraulic related troubles are common and recurrent to nuclear power plants worldwide. Japanese utilities are planning to introduce some of overseas experiences to their plants, such as power uprate and renovations of aged facilities. It is important to learn lessons from experiences paying close attention continuously to overseas trouble events, including thermal-hydraulics related events, and to use them to improve safety and reliability of nuclear power plants. (author)

Ultrasonic meters in the feedwater flow to recover thermal power in the reactor of nuclear power plant of Laguna Verde U1 and U2

International Nuclear Information System (INIS)

Tijerina S, F.

2008-01-01

The engineers in nuclear power plants BWRs and PWRs based on the development of the ultrasonic technology for the measurement of the mass, volumetric flow, density and temperature in fluids, have applied this technology in two primary targets approved by the NRC: the use for the recovery of thermal power in the reactor and/or to be able to realize an increase of thermal power licensed in a 2% (MUR) by 1OCFR50 Appendix K. The present article mentions the current problem in the measurement of the feedwater flow with Venturi meters, which affects that the thermal balance of reactor BWRs or PWRs this underestimated. One in broad strokes describes the application of the ultrasonic technology for the ultrasonic measurement in the flow of the feedwater system of the reactor and power to recover thermal power of the reactor. One is to the methodology developed in CFE for a calibration of the temperature transmitters of RTD's and the methodology for a calibration of the venturi flow transmitters using ultrasonic measurement. Are show the measurements in the feedwater of reactor of the temperature with RTD's and ultrasonic measurement, as well as the flow with the venturi and the ultrasonic measurement operating the reactor to the 100% of nominal thermal power, before and after the calibration of the temperature transmitters and flow. Finally, is a plan to be able to realize a recovery of thermal power of the reactor, showing as carrying out their estimations. As a result of the application of ultrasonic technology in the feedwater of reactor BWR-5 in Laguna Verde, in the Unit 1 cycle 13 it was recover an equivalent energy to a thermal power of 25 MWt in the reactor and an exit electrical power of 6 M We in the turbogenerator. Also in the Unit 2 cycle 10 it was recover an equivalent energy to a thermal power of 40 MWt in the reactor and an exit electrical power of 16 M We in the turbogenerator. (Author)

Product market competition and corporate governance

Directory of Open Access Journals (Sweden)

Julia Chou

2011-04-01

Full Text Available This paper investigates whether product market competition acts as an external mechanism for disciplining management and also whether there is any relationship between the degree of competition a firm faces and its corporate governance. We find that firms in competitive industries or with low market power tend to have weak corporate governance structures. Results are robust to various competition measures at firm and industry levels, even after controlling for firm-specific variables. We further find that corporate governance quality has a significant effect on performance only when product market competition is weak. The overall evidence suggests that product market competition has a substantial impact on corporate governance and that it substitutes for corporate governance quality. Finally, we provide evidence that the disciplinary force of competition on management is from the fear of liquidation.

Soil radioactivity levels and radiation hazard assessment around a Thermal Power Plant

International Nuclear Information System (INIS)

Kumar, Mukesh; Kumar, Pankaj; Sharma, Somdutt; Agrawal, Anshu; Kumar, Rajesh; Prajith, Rama; Sahoo, B.K.

2016-01-01

Coal based thermal power plants further enhance the level of radioactivity in the environment, as burning of coal produces fly ash that can be released into the environment containing traces of 238 U, 232 Th and their decay products. Therefore, coal fired power plants are one of the major contributor towards the Technologically Enhanced Natural Radiation (TENR). Keeping this in view, a study of natural radioactivity in the soil of twenty five villages within 5 km radius around the Harduaganj Thermal Power Plant, Aligarh, UP, India is going on under a BRNS major project, to know the radiological implications on general population living around this plant

Radioactive emission from thermal power plants

Energy Technology Data Exchange (ETDEWEB)

Okamoto, K [New South Wales Univ., Kensington (Australia). Dept. of Applied Mathematics

1981-07-01

Radioactive hazards of the emissions and wastes of thermal power plants arising from fuel impurities of uranium and thorium are discussed. The hazard due to radioactive emission is calculated for an average Australian bituminous coal which contains 2 ppm of U and 2.7 ppm of Th. When the dust removal efficiency of a coal-fired power plant is 99%, the radioactive hazard is greater than that of a nuclear reactor of the same electrical output. After 500 years the radioactive toxicity of the coal waste will be higher than that of fission products of a nuclear reactor and after 2,000 years it will exceed the toxicity of all the nuclear wastes including actinides. The results of a recent calculation are shown, according to which the radioactive hazard of a coal-fired power plant to the public is from several hundred to several tens of thousands of times higher than that of a total fuel cycle of plutonium. It is found that in some regions, such as Japan, the hazard due to /sup 210/Po through seafood could be considerable.

Thermal Modelling and Design of On-board DC-DC Power Converter using Finite Element Method

DEFF Research Database (Denmark)

Staliulionis, Z.; Zhang, Z.; Pittini, R.

2014-01-01

Power electronic converters are widely used and play a pivotal role in electronics area. The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determined...... by numerical modelling techniques. Therefore, thermal design through thermal modelling and simulation is becoming an integral part of the design process as less expensive compared to the experimental cut-and-try approach. Here the investigation is performed using finite element method-based modelling, and also...

Thermal Modeling and Design of On-board DC-DC Power Converter using Finite Element Method

DEFF Research Database (Denmark)

Staliulionis, Zygimantas; Zhang, Zhe; Pittini, Riccardo

2014-01-01

Power electronic converters are widely used and play a pivotal role in electronics area . The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determined...... by numerical modeling techniques. Therefore, thermal design through thermal modeling and simulation is becoming an integral part of the design process as less expensive compared to the experimenta l cut - and - try approach. Here the investigation is performed using finite element method - based modeling...

High-Temperature Air-Cooled Power Electronics Thermal Design: Annual Progress Report

Energy Technology Data Exchange (ETDEWEB)

Waye, Scot [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-08-01

Power electronics that use high-temperature devices pose a challenge for thermal management. With the devices running at higher temperatures and having a smaller footprint, the heat fluxes increase from previous power electronic designs. This project overview presents an approach to examine and design thermal management strategies through cooling technologies to keep devices within temperature limits, dissipate the heat generated by the devices and protect electrical interconnects and other components for inverter, converter, and charger applications. This analysis, validation, and demonstration intends to take a multi-scale approach over the device, module, and system levels to reduce size, weight, and cost.

Specifics of corporate management in agribusiness in transitional conditions

Directory of Open Access Journals (Sweden)

Vignjević-Đorđević Nada

2015-01-01

Full Text Available Corporate governance in agribusiness describes an agency problem resulting from separation of ownership from control in modern corporations and represents a huge cost to the shareholders. The agency problem is regulated by legal protection of minority shareholders, by constituting the Board of Directors as a Supervisory authority to monitor managers and an active agribusiness market for corporate control in agribusiness (against hostile takeover. These mechanisms are regulated by regulations on securities (at the federal level, corporate law (at the state level, and the corporate statutes, regulations and other Contracting Rules (at the company level. These regulations, laws and decrees actually define distribution of power between shareholders and managers. Such techniques of defense against takeover can be beneficial to shareholders, if managers use them to strengthen the bargaining power and increase the selling price of an agribusiness company. However, if managers use it for preservation of position and for the achievement of personal interests these regulations do not contribute to the realization of shareholders' interests.

A corporate social responsibility initiative in the field of nuclear power

International Nuclear Information System (INIS)

Stiopol, M.; Rizea, L.

2009-01-01

Societatea Nationala Nuclearelectrica SA is the operator of the Cernavoda nuclear power plant and the second largest energy producer in Romania, after Hidroelectrica, ensuring 18% of the internal energy demand. The production of nuclear power differs from other industrial activities through the risks it involves and through the legacy it leaves to the future generations, i.e. the nuclear waste. Taking into account these considerations, public acceptance represents a constant preoccupation for nuclear companies around the world. Corporate Social Responsibility (CSR) is a new practice in the nuclear industry. After a long tradition of involvement in the life of the local community through the Social Program for Cernavoda, Nuclearelectrica has initiated a CSR campaign with the theme 'Welcome a tree in your family', addressed to pupils and high school students from Cernavoda. By this campaign, we aimed at creating relevance, not just green lots and to launch a chain of reactions among the citizens of Cernavoda through 'word of mouth communication' so that our initiative may become a sustainable activity. In order to establish the basis of a long term program, the essential element was to change the attitude and behavior of the target population from lack of involvement to responsibility towards the environment. The ecological campaign developed in two phases of planting trees, has recorded significant results among the target population increasing the level of information and acceptance towards nuclear power. (authors)

Exergy analysis of the FIGUEIRA thermal power plant operation - state of Parana, Brazil

Energy Technology Data Exchange (ETDEWEB)

Stanescu, George; Lima, Joao E. [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica]. E-mails: stanescu@demec.ufpr.br; joeduli@demec.ufpr.br; Andrade, Carlos de [FIGUEIRA Thermal Power Plant, Figueira, PR (Brazil)]. E-mail: ccarlosaandrade@zipmail.com.br

2000-07-01

Exergy analysis is a powerful tool to evaluate, design and improve the thermal systems. The method of exergy analysis or availability analysis is well suited for furthering the goal of increasing the efficiency of existing power generation systems, and the capability of more effective energy resource use. Exergy analysis of the FIGUEIRA thermal power plant is presented. Exergy losses occurring in various components are considered and the exergy balance is shown in tabular form. Results clearly reveal that the steam generator is the principal site of thermodynamic losses, while the condenser is relatively unimportant. (author)

JT-60 power tests from mechanical and thermal viewpoints of tokamak machine

International Nuclear Information System (INIS)

Takatsu, H.; Yamamoto, M.; Ohkubo, M.

1986-01-01

JT-60 power tests were carried out, to demonstrate, in advance of actual plasma operation, satisfactory performance of the tokamak machine, power suppliers and control system in combination. The tests began with low power ones of individual coil systems, progressed to full power ones and concluded successfully. The present paper describes the principal results of JT-60 power tests from mechanical and thermal viewpoints of tokamak machine. All of the coil systems were raised up to full power operation in combination and system performance was verified including thermal and mechanical integrity of tokamak machine. Measured strain and displacement showed good agreements with those predicted in the design, which was an evidence that electromagnetic loads were supported adequately as expected in the design. Vibration of the vacuum vessel was found to be large up to 48 m/s/sup 2/ and caused excessive vibration of the lateral port gate-valves. A few limitations to machine operation were also made clear quantatively

Thermal Management of Power Semiconductor Packages - Matching Cooling Technologies with Packaging Technologies (Presentation)

Energy Technology Data Exchange (ETDEWEB)

Bennion, K.; Moreno, G.

2010-04-27

Heat removal for power semiconductor devices is critical for robust operation. Because there are different packaging options, different thermal management technologies, and a range of applications, there is a need for a methodology to match cooling technologies and package configurations to target applications. To meet this need, a methodology was developed to compare the sensitivity of cooling technologies on the overall package thermal performance over a range of power semiconductor packaging configurations. The results provide insight into the trade-offs associated with cooling technologies and package configurations. The approach provides a method for comparing new developments in power semiconductor packages and identifying potential thermal control technologies for the package. The results can help users select the appropriate combination of packaging configuration and cooling technology for the desired application.

Theoretical study on thermal stability of molten salt for solar thermal power

International Nuclear Information System (INIS)

Wei, Xiaolan; Peng, Qiang; Ding, Jing; Yang, Xiaoxi; Yang, Jianping; Long, Bin

2013-01-01

Molten salt (HTS) composed of 53% KNO 3 , 40% NaNO 2 and 7 wt.% NaNO 3 has been used as heat transfer media and thermal storage fluid in the solar thermal power, but thermal decomposition will occur at higher temperature because of the oxidation of nitrite to nitrate in the air. In this paper, the reaction mechanism of NO 2 − oxidation is researched by quantum mechanical method. The results show that two components of the transition state (O 2 NO 2 − ) and intermediate ([NO 4 − ]) are found in the reaction. This reaction is an exothermic reaction and the activation barrier is 94.0 kJ mol −1 . The energy difference of this reaction is very large, so the reaction rate is very slow. -- Highlights: ► The mechanism of the oxidation of nitrite salt in HTS is explained. ► Two components of the transition state (O 2 NO 2 − ) and intermediate ([NO 4 − ]) are found. ► The activation barrier of the nitrite oxidation is determined

Source driven breeding thermal power reactors

International Nuclear Information System (INIS)

Greenspan, E.; Schneider, A.; Misulovin, A.; Gilai, D.; Levin, P.; Ben-Gurion Univ. of the Negev, Beersheba

1978-03-01

Improvements in the performance of fission power reactors made possible by designing them subcritical driven by D-T neutron sources are investigated. Light-water thermal systems are found to be most promising, neutronically and energetically, for the source driven mode of operation. The range of performance characteristics expected from breeding Light Water Hybrid Reactors (LWHR) is defined. Several promising types of LWHR blankets are identified. Options opened for the nuclear energy strategy by four types of the LWHRs are examined, and the potential contribution of these LWHRs to the nuclear energy economy are discussed. The power systems based on these LWHRs are found to enable a high utilization of the energy content of the uranium resources in all forms available - including depleted uranium and spent fuel from LWRs, while being free from the need for uranium enrichment and plutonium separation capabilities. (author)

Similarities and differences between conventional power and nuclear power

International Nuclear Information System (INIS)

Wang Yingrong

2011-01-01

As the implementation of the national guideline of 'proactively promoting nuclear power development', especially after China decided in 2006 to introduce Westinghouse's AP1000 technology, some of the power groups specialized in conventional power generation, have been participating in the preliminary work and construction of nuclear power projects in certain degrees. Meanwhile, such traditional nuclear power corporations as China National Nuclear Corporation (CNNC) and China Guangdong Nuclear Power Corporation (CGNPC) have also employed some employees with conventional power generation experience. How can these employees who have long been engaged in conventional power generation successfully adapt to the new work pattern, ideology, knowledge, thinking mode and proficiency of nuclear power, so that they can fit in with the work requirements of nuclear power and become qualified as soon as possible? By analyzing the technological, managerial and cultural features of nuclear power, as well as some issues to be kept in mind when engaged in nuclear power, this paper intends to make some contribution to the nuclear power development in the specific period. (author)

Unitary theory of xenon instability in nuclear thermal reactors - 1. Reactor at 'zero power'

International Nuclear Information System (INIS)

Novelli, A.

1982-01-01

The question of nuclear thermal-reactor instability against xenon oscillations is widespread in the literature, but most theories, concerned with such an argument, contradict each other and, above all, they conflict with experimentally-observed instability at very low reactor power, i.e. without any power feedback. It is shown that, in any nuclear thermal reactor, xenon instability originates at very low power levels, and a very general stability condition is deduced by an extension of the rigorous, simple and powerful reduction of the Nyquist criterion, first performed by F. Storrer. (author)

Air quality assessment in the vicinity of nuclear and thermal power stations

International Nuclear Information System (INIS)

Sivaramasundaram, K.; Vijay Bhaskar, B.; Muthusubramanian, P.; Rajan, M.P.; Hegde, A.G.

2007-01-01

The status and ranking of any country, in the context of globalisation, is decided by its economic progress, which is directly linked into power generation. The power is generated by many routes and the nuclear and thermal routes are noteworthy among them. As the power production and its associated activities may cause qualitative deterioration, it is essential to study the impact of power production on atmospheric environment. In this connection, a comparative study has been carried out to assess the air quality with special reference to criteria pollutants in the vicinity of nuclear and thermal power stations. In the present investigation, the air samples are collected on weekly basis and the pollutants such as sulphur dioxide (SO 2 ), nitrogen oxides (NOx), carbon monoxide (CO), suspended particulate matter (SPM) and respirable particulate matter (RPM) are estimated by adopting standard procedures set by United States-Environmental Protection Agency (US-EPA) and Central Pollution Control Board (CPCB). As the micro meteorological parameters influence on the status of air quality, simultaneous measurements of these parameters are also carried, out during sampling. It is studied that estimated concentrations of all criteria pollutants in the vicinity of these power stations are within the permissible limits set by CPCB. On the basis of the generated database pertaining to the concentrations of criteria air pollutants in the vicinity of nuclear and thermal power stations, it is concluded that nuclear power production may be considered as a viable option in terms of environmental protection in our country. (author)

Fuel management service for Tarapur Atomic Power Station core thermal hydraulics

International Nuclear Information System (INIS)

Saha, D.; Venkat Raj, V.; Markandeya, S.G.

1977-01-01

Core thermal hydraulic analysis forms an integral part of the fuel management service for the Tarapur reactors. A distinguishing feature of boiling water reactors is the dependence of core flow distribution on the power distribution. Because of the changes in the axial and radial power distribution from cycle to cycle as well as during the cycle and also the variations in leakage flow, it is necessary to evaluate the core thermal hydraulic parameters for every cycle. Some of the typical results obtained in the course of analysis for different cycles of both the units at Tarapur are presented. The use of MCPR (Minimum Critical Power Ratio), instead of MCHFR (Minimum Critical Heat Flux Ratio) as a figure of merit for fuel cladding integrity is also discussed. (K.B.)

The Discourses of Corporate Spiritualism and Evangelical Capitalism.

Science.gov (United States)

Nadesan, Majia Holmer

1999-01-01

Explores the growth of literature proposing corporate spirituality as a means of motivating employees. Suggests that critical analysis articulates and advocates two entrepreneurial views of subjecthood that obscure contemporary corporate power by centering the individual as an autonomous agent. Concludes that these discourses reinforce social…

System Description of the Electrical Power Supply System for the ATLAS Integral Test Loop

International Nuclear Information System (INIS)

Moon, S. K.; Park, J. K.; Kim, Y. S.; Song, C. H.; Baek, W. P.

2007-02-01

An integral effect test loop for pressurized water reactors (PWRs), the ATLAS (Advanced Thermal-hydraulic Test Loop for Accident Simulation), is constructed by Thermal-Hydraulics Safety Research Team in Korea Atomic Energy Research Institute (KAERI). The ATLAS facility has been designed to have the length scale of 1/2 and area scale of 1/144 compared with the reference plant, APR1400. This report describes the design and technical specifications of the electrical power supply system which supplies the electrical powers to core heater rods, other heaters, various pumps and other systems. The electrical power supply system had acquired the final approval on the operation from the Korea Electrical Safety Corporation. During performance tests for the operation and control, the electrical power supply system showed completely acceptable operation and control performance

A new high power thermal battery cathode material

International Nuclear Information System (INIS)

Faul, I.

1986-01-01

Smaller and lighter thermal batteries are major aims of the battery research programme at RAE Farnborough. Modern designs of thermal batteries, for use as power supplies in weapon systems, almost invariably use the Li:molten salt:FeS/sub 2/ system because of the significant increase in energy density achieved in comparison with the earlier Ca/CaCrO/sub 4/ couple. The disadvantage of the FeS/sub 2/ system is that the working cell voltage, between 1.5 and 2.0 V, is significantly lower so leading to more cells per battery than the earlier system. Further work at RAE and MSA (Britain) Ltd showed that the poor thermal stability of TiS/sub 2/ limited its use in thermal batteries, whilst the more stable V/sub 6/O/sub 13/ oxidised the electrolyte, giving poor efficiencies. However, the resulting reduced vanadium oxide material, subsequently called lithiated vanadium oxide (LVO), was found to be an excellent high voltage thermal battery cathode, being the subject of both UK and US patents. In this study both V/sub 6/O/sub 13/ made by the direct stoichiometric reaction of V/sub 2/O/sub 5/ and V and also by thermal decomposition of NH/sub 4/VO/sub 3/ under argon, have been used with equal success as the starting material for the preparation of LVO

Impact of environmental cost on economics of thermal power plant. Paper no. IGEC-1-007

International Nuclear Information System (INIS)

Chandra, H.; Kaushik, S.C.; Chandra, A.

2005-01-01

Cost analysis per unit of power generation have been performed for coal based thermal power plant situated in Dadri (UP) for Indian and imported coal from Australia and America. In our study it has been found that it is better to use imported coal in Indian thermal power plants with advantages like low environmental, investment and total cost per unit of power generation. The effect of percent excess air and plant load factor on total cost per unit of power generation is also analyzed. (author)

The thermal relay design to improve power system security for the HTS cables in Icheon substation

International Nuclear Information System (INIS)

Lee, Hansang; Yang, Byeong-Mo; Jang, Gilsoo

2013-01-01

Highlights: •It is important to study thermal characteristics of the HTS cable. •The thermal relay in the Icheon substation has been developed. •Well-designed thermal relay has been verified through PSCAD/EMTDC simulations. -- Abstract: This paper proposes a model for thermal protection relay for the high temperature superconducting (HTS) cables and thermal protection scheme in Icheon substation in Korea. The thermal protection is one of the most important factors to guarantee the reliability of the HTS cable as well as power system security. The superconductivity of the HTS cables, which can be guaranteed by the liquid nitrogen near 70 K, can be threatened by the large fault current. To avoid the overheating in HTS cable and to secure the power system operation with the HTS cable, the thermal protection relay should be considered. To find the optimal thermal-protection scheme, the model for the superconducting power system has been achieved in Icheon substation and the thermal protection scheme has been verified through PSCAD/EMTDC simulation

The thermal relay design to improve power system security for the HTS cables in Icheon substation

Energy Technology Data Exchange (ETDEWEB)

Lee, Hansang, E-mail: hslee80@kiu.ac.kr [School of Railway and Electrical Engineering, Kyungil University, Hayang-eup, Gyeongsan-si, Gyeongsangbuk-do 712-701 (Korea, Republic of); Yang, Byeong-Mo [Korea Electric Power Research Institute, Munji-dong, Yuseong-gu, Daejeon 305-760 (Korea, Republic of); Jang, Gilsoo, E-mail: gjang@korea.ac.kr [School of Electrical Engineering, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-713 (Korea, Republic of)

2013-11-15

Highlights: •It is important to study thermal characteristics of the HTS cable. •The thermal relay in the Icheon substation has been developed. •Well-designed thermal relay has been verified through PSCAD/EMTDC simulations. -- Abstract: This paper proposes a model for thermal protection relay for the high temperature superconducting (HTS) cables and thermal protection scheme in Icheon substation in Korea. The thermal protection is one of the most important factors to guarantee the reliability of the HTS cable as well as power system security. The superconductivity of the HTS cables, which can be guaranteed by the liquid nitrogen near 70 K, can be threatened by the large fault current. To avoid the overheating in HTS cable and to secure the power system operation with the HTS cable, the thermal protection relay should be considered. To find the optimal thermal-protection scheme, the model for the superconducting power system has been achieved in Icheon substation and the thermal protection scheme has been verified through PSCAD/EMTDC simulation.

Turbostar: an ICF reactor using both direct and thermal power conversion. Revision 1

International Nuclear Information System (INIS)

Pitts, J.H.

1986-01-01

Combining direct and thermal power conversion results in a 52% gross plant efficiency with DT fuel and 68% with advanced DD fuel. We maximize the fraction of fusion-yield energy converted to kinetic energy in a liquid-lithium blanket, and use this energy directly with turbine generators to produce electricity. We use the remainder of the energy to produce electricity in a standard Rankine thermal power conversion cycle

Hot Thermal Storage in a Variable Power, Renewable Energy System

Science.gov (United States)

2014-06-01

where cost effective, increase the utilization of distributed electric power generation through wind, solar, geothermal , and biomass renewable...characteristics and may not necessarily be available in all cases. Types of direct heat energy systems include solar thermal, waste heat, and geothermal ...of super capacitor energy storage system in microgrid,” in International Conference on Sustainable Power Generation and Supply, Janjing, China

Engineering aspects of a thermal control subsystem for the 25 kW power module

Science.gov (United States)

Schroeder, P. E.

1979-01-01

The paper presents the key trade study results, analysis results, and the recommended thermal control approach for the 25 kW power module defined by NASA. Power conversion inefficiencies and component heat dissipation results in a minimum heat rejection requirement of 9 kW to maintain the power module equipment at desired temperature levels. Additionally, some cooling capacity should be provided for user payloads in the sortie and free-flying modes. The baseline thermal control subsystem includes a dual-loop-pumped Freon-21 coolant with the heat rejected from deployable existing orbiter radiators. Thermal analysis included an assessment of spacecraft orientations, radiator shapes and locations, and comparison of hybrid heat pipe and all liquid panels.

Efficiency assessment and benchmarking of thermal power plants in India

International Nuclear Information System (INIS)

Shrivastava, Naveen; Sharma, Seema; Chauhan, Kavita

2012-01-01

Per capita consumption of electricity in India is many folds lesser than Canada, USA, Australia, Japan, Chaina and world average. Even though, total energy shortage and peaking shortage were recorded as 11.2% and 11.85%, respectively, in 2008–09 reflecting non-availability of sufficient supply of electricity. Performance improvement of very small amount can lead to large contribution in financial terms, which can be utilized for capacity addition to reduce demand supply gap. Coal fired thermal power plants are main sources of electricity in India. In this paper, relative technical efficiency of 60 coal fired power plants has been evaluated and compared using CCR and BCC models of data envelopment analysis. Target benchmark of input variables has also been evaluated. Performance comparison includes small versus medium versus large power plants and also state owned versus central owned versus private owned. Result indicates poor performance of few power plants due to over use of input resources. Finding reveals that efficiency of small power plants is lower in comparison to medium and large category and also performance of state owned power plants is comparatively lower than central and privately owned. Study also suggests different measures to improve technical efficiency of the plants. - Highlights: ► This study evaluates relative technical efficiency of 60 coal fired thermal power plants of India. ► Input oriented CCR and BCC models of data envelopment analysis have been used. ► Small, medium and large power plants have been compared. ► Study will help investor while setting up new power projects. ► Power plants of different ownerships have also been compared.

Emerging Changes in the Worldwide Power Sector: The Assets of Thermal Power

Energy Technology Data Exchange (ETDEWEB)

Moliere, Michel; Girardot, Amelie; Jones, Robert M.

2007-07-01

In forthcoming decades we will see major changes in the landscape of the worldwide power sector as CO2 management and incipient hydrocarbon scarcity exert their increasing influence. The power generation community must be prepared to satisfy a particularly complex and challenging set of requirements. These issues include curbing CO2 emissions, coping with surging primary energy prices, and compliance with regional and local emissions requirements such as SOx and NOx-while maintaining maximum efficiency. In this context, as confirmed by International Energy Agency forecasts, thermal power will maintain a prominent position in overall power generation since it enables the large capacity additions required in emerging countries. Thanks to their reliable assets (such as energy efficiency and environment) gas turbine-based power systems, including Gas Turbine Combined Cycles (GTCC) and Combined Heat & Power (CHP), will continue to be major contributors to worldwide power generation. However, evolving changes in the spectrum of fuels will create an additional challenge for power generation equipment manufacturers-requiring innovative technologies in fuel processing, combustion, and emission controls to address these needs. This paper reviews the factors underlining the changing power generation environment worldwide, including the increasing scarcity of conventional fuels and the growing interest in biofuels and hydrogen. Insights will be offered into various technologies needed to support the growing need for increased fuel flexibility.

RAM investigation of coal-fired thermal power plants: A case study

Directory of Open Access Journals (Sweden)

D. Bose

2012-04-01

Full Text Available Continuous generation of electricity of a power plant depends on the higher availability of its components/equipments. Higher availability of the components/equipments is inherently associated with their higher reliability and maintainability. This paper investigates the reliability, availability and maintainability (RAM characteristics of a 210 MW coal-fired thermal power plant (Unit-2 from a thermal power station in eastern region of India. Critical mechanical subsystems with respect to failure frequency, reliability and maintainability are identified for taking necessary measures for enhancing availability of the power plant and the results are compared with Unit-1 of the same Power Station. Reliability-based preventive maintenance intervals (PMIs at various reliability levels of the subsystems are estimated also for performing their preventive maintenance (PM. The present paper highlights that in the Unit-2, Economizer (ECO & Furnace Wall Tube (FWT exhibits lower reliability as compared to the other subsystems and Economizer (ECO & Baffle Wall Tube (BWT demands more improvement in maintainability. Further, it has been observed that FSH followed Decreasing Failure Rate (DFR and Economizer (ECO is the most critical subsystem for both the plants. RAM analysis is very much effective in finding critical subsystems and deciding their preventive maintenance program for improving availability of the power plant as well as the power supply.

A 3D Lumped Thermal Network Model for Long-term Load Profiles Analysis in High Power IGBT Modules

DEFF Research Database (Denmark)

Bahman, Amir Sajjad; Ma, Ke; Ghimire, Pramod

2016-01-01

)-based simulation is another method which is often used to analyze the steady-state thermal distribution of IGBT modules, but it is not possible to be used for long-term analysis of load profiles of power converter, which is needed for reliability assessments and better thermal design. This paper proposes a novel...... enables both accurate and fast temperature estimation of high power IGBT modules in the real loading conditions of the converter; meanwhile the critical details of the thermal dynamics and thermal distribution are also maintained. The proposed thermal model is verified by both FEM simulation......The conventional RC lumped thermal networks are widely used to estimate the temperature of power devices, but they are lack of accuracy in addressing detailed thermal behaviors/couplings in different locations and layers of the high power IGBT modules. On the other hand, Finite Element (FE...

Effects of Thermal Cycling on Control and Irradiated EPC 2nd Generation GaN FETs

Science.gov (United States)

Patterson, Richard L.; Scheick, Leif; Lauenstein, Jean-Marie; Casey, Megan; Hammoud, Ahmad

2013-01-01

The power systems for use in NASA space missions must work reliably under harsh conditions including radiation, thermal cycling, and exposure to extreme temperatures. Gallium nitride semiconductors show great promise, but information pertaining to their performance is scarce. Gallium nitride N-channel enhancement-mode field effect transistors made by EPC Corporation in a 2nd generation of manufacturing were exposed to radiation followed by long-term thermal cycling in order to address their reliability for use in space missions. Results of the experimental work are presented and discussed.

An integrated solar thermal power system using intercooled gas turbine and Kalina cycle

International Nuclear Information System (INIS)

Peng, Shuo; Hong, Hui; Jin, Hongguang; Wang, Zhifeng

2012-01-01

A new solar tower thermal power system integrating the intercooled gas turbine top cycle and the Kalina bottoming cycle is proposed in the present paper. The thermodynamic performance of the proposed system is investigated, and the irreversibility of energy conversion is disclosed using the energy–utilization diagram method. On the top cycle of the proposed system, the compressed air after being intercooled is heated at 1000 °C or higher at the solar tower receiver and is used to drive the gas turbine to generate power. The ammonia–water mixture as the working substance of the bottom cycle recovers the waste heat from the gas turbine to generate power. A concise analytical formula of solar-to-electric efficiency of the proposed system is developed. As a result, the peak solar-to-electric efficiency of the proposed system is 27.5% at a gas turbine inlet temperature of 1000 °C under the designed solar direct normal irradiance of 800 W/m 2 . Compared with a conventional solar power tower plant, the proposed integrated system conserves approximately 69% of consumed water. The results obtained in the current study provide an approach to improve solar-to-electric efficiency and offer a potential to conserve water for solar thermal power plants in arid area. -- Highlights: ► An Integrated Solar Thermal Power System is modeled. ► A formula forecasting the thermodynamic performance is proposed. ► The irreversibility of energy conversion is disclosed using an energy utilization method. ► The effect of key operational parameters on thermal performance is examined.

A Novel Method To On-Line Monitor Reactor Nuclear Power And In-Core Thermal Environments

International Nuclear Information System (INIS)

Liu, Hanying; Miller, Don W.; Li, Dongxu; Radcliff, Thomas D.

2002-01-01

For current nuclear power plants, nuclear power can not be directly measured and in-core fuel thermal environments can not be monitored due to the unavailability of an appropriate measurement technology and the inaccessibility of the fuel. If the nuclear deposited power and the in-core thermal conditions (i.e. fuel or coolant temperature and heat transfer coefficient) can be monitored in-situ, then it would play a valuable and critical role in increasing nuclear power, predicting abnormal reactor operation, improving core physical models and reducing core thermal margin so as to implement higher fuel burn-up. Furthermore, the management of core thermal margin and fuel operation may be easier during reactor operation, post-accident or spent fuel storage. On the other hand, for some advanced Generation IV reactors, the sealed and long-lived reactor core design challenges traditional measurement techniques while conventional ex-core detectors and current in-core detectors can not monitor details of the in-core fuel conditions. A method is introduced in this paper that responds to the challenge to measure nuclear power and to monitor the in-core thermal environments, for example, local fuel pin or coolant heat convection coefficient and temperature. In summary, the method, which has been designed for online in-core measurement and surveillance, will be beneficial to advanced plant safety, efficiency and economics by decreasing thermal margin or increasing nuclear power. The method was originally developed for a constant temperature power sensor (CTPS). The CTPS is undergoing design and development for an advanced reactor core to measure in-core nuclear power in measurement mode and to monitor thermal environments in compensation mode. The sensor dynamics was analyzed in compensation mode to determine the environmental temperature and the heat transfer coefficient. Previous research demonstrated that a first order dynamic model is not sufficient to simulate sensor

Molten Salt-Carbon Nanotube Thermal Energy Storage for Concentrating Solar Power Systems Final Report

Energy Technology Data Exchange (ETDEWEB)

Michael Schuller; Frank Little; Darren Malik; Matt Betts; Qian Shao; Jun Luo; Wan Zhong; Sandhya Shankar; Ashwin Padmanaban

2012-03-30

We demonstrated that adding nanoparticles to a molten salt would increase its utility as a thermal energy storage medium for a concentrating solar power system. Specifically, we demonstrated that we could increase the specific heat of nitrate and carbonate salts containing 1% or less of alumina nanoparticles. We fabricated the composite materials using both evaporative and air drying methods. We tested several thermophysical properties of the composite materials, including the specific heat, thermal conductivity, latent heat, and melting point. We also assessed the stability of the composite material with repeated thermal cycling and the effects of adding the nanoparticles on the corrosion of stainless steel by the composite salt. Our results indicate that stable, repeatable 25-50% improvements in specific heat are possible for these materials. We found that using these composite salts as the thermal energy storage material for a concentrating solar thermal power system can reduce the levelized cost of electricity by 10-20%. We conclude that these materials are worth further development and inclusion in future concentrating solar power systems.

Comparative exergetic performance analysis for certain thermal power plants in Serbia

Directory of Open Access Journals (Sweden)

Mitrović Dejan M.

2016-01-01

Full Text Available Traditional methods of analysis and calculation of complex thermal systems are based on the first law of thermodynamics. These methods use energy balance for a system. In general, energy balances do not provide any information about internal losses. In contrast, the second law of thermodynamics introduces the concept of exergy, which is useful in the analysis of thermal systems. Exergy is a measure for assessing the quality of energy, and allows one to determine the location, cause, and real size of losses incurred as well as residues in a thermal process. The purpose of this study is to comparatively analyze the performance of four thermal power plants from the energetic and exergetic viewpoint. Thermodynamic models of the plants are developed based on the first and second law of thermodynamics. The primary objectives of this paper are to analyze the system components separately and to identify and quantify the sites having largest energy and exergy losses. Finally, by means of these analyses, the main sources of thermodynamic inefficiencies as well as a reasonable comparison of each plant to others are identified and discussed. As a result, the outcomes of this study can provide a basis for the improvement of plant performance for the considered thermal power plants.

Certain aspects of the environmental impact of nuclear power engineering and thermal power engineering

Energy Technology Data Exchange (ETDEWEB)

Malenchenko, A F [AN Belorusskoj SSR, Minsk. Inst. Yadernoj Ehnergetiki

1979-01-01

A review is made of the both environmental impact and hazard to man resulting from nuclear power engineering as compared with those of thermal power engineering. At present, in addition to such criteria, as physical-chemical characteristic of energy sources, their efficiency and accessibility for exploitation, new requirements were substantiated in relation to safety of their utilization for environment. So, one of essential problems of nuclear power engineering development consists in assessment and prediction of radioecological consequence. The analysis and operating experience of more than 1000 reactor/years with no accidents and harm for pupulation show, that in respect to impact on environment and man nuclear power engineering is much more safe in comparison with energy sources using tradidional fossile fuel.

Ecological and economic interests in design process of thermal power plant

International Nuclear Information System (INIS)

Sander, M.

1996-01-01

In design process of thermal power plant various ecological and economic contradictory interests are brought in focus. Requests on environmental protection written in laws, standards and international treaties are increasing investment costs and energy production costs. In a design phase there is a task to reconcile these contradictory requests. The paper presents relationship between technology and environmental protection with a focus on air pollution. Air pollution and human health is considered taking in account the role of design phase in thermal power plants project and human health problems. International laws and standards are presented with moral dilemmas concerning low investment costs and high environmental standards. (author)

Cost and performance analysis of concentrating solar power systems with integrated latent thermal energy storage

International Nuclear Information System (INIS)

Nithyanandam, K.; Pitchumani, R.

2014-01-01

Integrating TES (thermal energy storage) in a CSP (concentrating solar power) plant allows for continuous operation even during times when solar irradiation is not available, thus providing a reliable output to the grid. In the present study, the cost and performance models of an EPCM-TES (encapsulated phase change material thermal energy storage) system and HP-TES (latent thermal storage system with embedded heat pipes) are integrated with a CSP power tower system model utilizing Rankine and s-CO 2 (supercritical carbon-dioxide) power conversion cycles, to investigate the dynamic TES-integrated plant performance. The influence of design parameters of the storage system on the performance of a 200 MW e capacity power tower CSP plant is studied to establish design envelopes that satisfy the U.S. Department of Energy SunShot Initiative requirements, which include a round-trip annualized exergetic efficiency greater than 95%, storage cost less than $15/kWh t and LCE (levelized cost of electricity) less than 6 ¢/kWh. From the design windows, optimum designs of the storage system based on minimum LCE, maximum exergetic efficiency, and maximum capacity factor are reported and compared with the results of two-tank molten salt storage system. Overall, the study presents the first effort to construct and analyze LTES (latent thermal energy storage) integrated CSP plant performance that can help assess the impact, cost and performance of LTES systems on power generation from molten salt power tower CSP plant. - Highlights: • Presents technoeconomic analysis of thermal energy storage integrated concentrating solar power plants. • Presents a comparison of different storage options. • Presents optimum design of thermal energy storage system for steam Rankine and supercritical carbon dioxide cycles. • Presents designs for maximizing exergetic efficiency while minimizing storage cost and levelized cost of energy

Thermal Equilibrium Dynamic Control Based on DPWM Dual-Mode Modulation of High Power NPC Three-Level Inverter

Directory of Open Access Journals (Sweden)

Shi-Zhou Xu

2016-01-01

Full Text Available In some special applications of NPC three-level inverters, such as mine hoist, there exist special conditions of overloading during the whole hoisting process and large overload in starting stage, during which the power-loss calculation of power devices and thermal control are important factors affecting the thermal stability of inverters. The principles of SVPWM and DPWM were described in this paper firstly, based on which the dynamic power losses of the two modulations of hoist in single period were calculated. Secondly, a thermal equilibrium dynamic control based on DPMW dual-mode modulation was proposed, which can switch the modulation dynamically according to the change of dynamic power loss to realize dynamic control of power loss and thermal equilibrium of inverter. Finally, simulation and experiment prove the effectiveness of the proposed strategy.

Neutron flux measurement and thermal power calibration of the IAN-R1 TRIGA reactor

Energy Technology Data Exchange (ETDEWEB)

Sarta Fuentes, Jose A.; Castiblanco Bohorquez, Luis A

2008-10-29

The IAN-R1 TRIGA reactor in Colombia was initially fueled with MTR-HEU enriched to 93% U-235, operated since 1965 at 10 kW, and was upgraded to 30 kW in 1980. General Atomics achieved in 1997 the conversion of HEU fuel to LEU fuel TRIGA type, and upgraded the reactor power to 100 kW. Since the IAN-R1 TRIGA reactor was in an extended shutdown during seven years, it was necessary to repeat some results of the commissioning test conducted in 1997. The thermal power calibration was carried out using the calorimetric method. The reactor was operated approximately at 20 kW during 3.5 hours, with manual power corrections since the automatic control system failed and with the forced refrigeration off. During the calorimetric experiment, the pool temperature was measured with a RTD which is installed near to the core. The dates were collected in intervals of 30 minutes. For establishing thermal power reactor, the water temperature versus the running were registered. For a calculated tank volume of 16 m{sup 3}, the tank constant calculated for the IAN-R1 TRIGA reactor is 0.0539 C/kW-hr. The reactor power determined was 19 kW. The core configuration is a rectangular grid plate that holds a combination of 4-rod and 3-rod clusters. The core contains 50 fuel rods with LEU fuel TRIGA (UZr H1.6) type enriched to 19.7%. The radial reflector consists of twenty graphite elements six of which are used for isotope production. The top an bottom reflectors are the cylindrical graphite end reflectors which are installed above and below of the active fuel section in each fuel rod. The spatial dependence of thermal neutron flux was measured axially in the 3-rod clusters 4C, 3D, 5E and in the 4F graphite element. The spatial distribution of the thermal neutron was determined using a self-powered detector and the absolute value of thermal neutron flux was determined by a gold activation detector. The (n, b- ) reaction is applied to determine the relative spatial distribution of thermal

Transnational politics and translocal governance: The politics of corporate responsibility

OpenAIRE

Banerjee, S. B.

2017-01-01

In this article, I provide a critical analysis of the politics of corporate social responsibility. I argue that corporate social responsibility is a strategy that enables multinational corporations to exercise power in the global political economy. Using the global extractive industries as a context, I focus on conflicts between communities, the state and multinational corporations that arise owing to the negative social and environmental impacts of mining and extraction. In particular, I ana...

Method of operating a thermal engine powered by a chemical reaction

Science.gov (United States)

Ross, J.; Escher, C.

1988-06-07

The invention involves a novel method of increasing the efficiency of a thermal engine. Heat is generated by a non-linear chemical reaction of reactants, said heat being transferred to a thermal engine such as Rankine cycle power plant. The novel method includes externally perturbing one or more of the thermodynamic variables of said non-linear chemical reaction. 7 figs.

Human body heat for powering wearable devices: From thermal energy to application

International Nuclear Information System (INIS)

Thielen, Moritz; Sigrist, Lukas; Magno, Michele; Hierold, Christofer; Benini, Luca

2017-01-01

Highlights: • A complete system optimization for wearable thermal harvesting from body heat to the application is proposed. • State-of-the-art thermal harvesters and DC-DC converters are compared and classified. • Extensive simulation and experiments are carried out to characterize the harvesting performance. • A case study demonstrates the feasibility to supply a multi-sensor wearables only from body heat. - Abstract: Energy harvesting is the key technology to enable self-sustained wearable devices for the Internet of Things and medical applications. Among various types of harvesting sources such as light, vibration and radio frequency, thermoelectric generators (TEG) are a promising option due to their independence of light conditions or the activity of the wearer. This work investigates scavenging of human body heat and the optimization of the power conversion efficiency from body core to the application. We focus on the critical interaction between thermal harvester and power conditioning circuitry and compare two approaches: (1) a high output voltage, low thermal resistance μTEG combined with a high efficiency actively controlled single inductor DC-DC converter, and (2) a high thermal resistance, low electric resistance mTEG in combination with a low-input voltage coupled inductors based DC-DC converter. The mTEG approach delivers up to 65% higher output power per area in a lab setup and 1–15% in a real-world experiment on the human body depending on physical activity and environmental conditions. Using off-the-shelf and low-cost components, we achieve an average power of 260 μW (μTEG) to 280 μW (mTEG) and power densities of 13 μW cm"−"2 (μTEG) to 14 μW cm"−"2 (mTEG) for systems worn on the human wrist. With the small and lightweight harvesters optimized for wearability, 16% (mTEG) to 24% (μTEG) of the theoretical maximum efficiency is achieved in a worst-case scenario. This efficiency highly depends on the application specific conditions

3D model of steam generator of nuclear power plant Krsko

International Nuclear Information System (INIS)

Ravnikar, I.; Petelin, S.

1995-01-01

The Westinghouse Electric Corporation D4 steam generator design was analyzed from a thermal-hydraulic point of view using the 3D PHOENICS computer code. Void fraction, velocity and enthalpy distributions were obtained in the U-tube riser. The boundary conditions of primary side were provided by SMUP 1D code. The calculations were carried out for present operating conditions of nuclear power plant Krsko. (author)

Assessment of the Impacts of Green Mountain Power Corporation's Wind Power Facility on Breeding and Migrating Birds in Searsburg, Vermont: July 1996--July 1998

Energy Technology Data Exchange (ETDEWEB)

Kerlinger, P.

2002-03-01

A 6-megawatt, 11 turbine wind power development was constructed by Green Mountain Power Corporation in Searsburg, southern Vermont, in 1996. To determine whether birds were impacted, a series of modified BA (Before, After) studies was conducted before construction (1993-1996), during (1996), and after (1997) construction on the project site. The studies were designed to monitor changes in breeding bird community (species composition and abundance) on the site, examine the behavior and numbers of songbirds migrating at night over the site and hawks migrating over the site in daylight, and search for carcasses of birds that might have collided with the turbines.

Applications of laser diagnostics to thermal power plants and engines

International Nuclear Information System (INIS)

Deguchi, Y.; Kamimoto, T.; Wang, Z.Z.; Yan, J.J.; Liu, J.P.; Watanabe, H.; Kurose, R.

2014-01-01

The demands for lowering the burdens on the environment will continue to grow steadily. It is important to monitor controlling factors in order to improve the operation of industrial thermal systems. In engines, exhaust gas temperature and concentration distributions are important factors in nitrogen oxides (NO x ), total hydrocarbon (THC) and particulate matter (PM) emissions. Coal and fly ash contents are parameters which can be used for the control of coal-fired thermal power plants. Monitoring of heavy metals such as Hg is also important for pollution control. In this study, the improved laser measurement techniques using computed tomography-tunable diode laser absorption spectroscopy (CT-TDLAS), low pressure laser-induced breakdown spectroscopy (LIBS), and laser breakdown time-of-flight mass spectrometry (LB-TOFMS) have been developed and applied to measure 2D temperature and species concentrations in engine exhausts, coal and fly ash contents, and trace species measurement. The 2D temperature and NH 3 concentration distributions in engine exhausts were successfully measured using CT-TDLAS. The elemental contents of size-segregated particles were measured and the signal stability increased using LIBS with the temperature correction method. The detection limit of trace species measurement was enhanced using low pressure LIBS and LB-TOFMS. The detection limit of Hg can be enhanced to 3.5 ppb when employing N 2 as the buffer gas using low pressure LIBS. Hg detection limit was about 0.82 ppb using 35 ps LB-TOFMS. Compared to conventional measurement methods laser diagnostics has high sensitivity, high response and non-contact features for actual industrial systems. With these engineering developments, transient phenomena such as start-ups in thermal systems can be evaluated to improve the efficiency of these thermal processes. - Highlights: • Applicability of newly developed laser diagnostics was demonstrated for the improvement of thermal power plants and

Selection of high temperature thermal energy storage materials for advanced solar dynamic space power systems

Science.gov (United States)

Lacy, Dovie E.; Coles-Hamilton, Carolyn; Juhasz, Albert

1987-01-01

Under the direction of NASA's Office of Aeronautics and Technology (OAST), the NASA Lewis Research Center has initiated an in-house thermal energy storage program to identify combinations of phase change thermal energy storage media for use with a Brayton and Stirling Advanced Solar Dynamic (ASD) space power system operating between 1070 and 1400 K. A study has been initiated to determine suitable combinations of thermal energy storage (TES) phase change materials (PCM) that result in the smallest and lightest weight ASD power system possible. To date the heats of fusion of several fluoride salt mixtures with melting points greater than 1025 K have been verified experimentally. The study has indicated that these salt systems produce large ASD systems because of their inherent low thermal conductivity and low density. It is desirable to have PCMs with high densities and high thermal conductivities. Therefore, alternate phase change materials based on metallic alloy systems are also being considered as possible TES candidates for future ASD space power systems.

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

A study on the ocean circulation and thermal diffusion near a nuclear power plant

International Nuclear Information System (INIS)

Shu, Kyung Suk; Han, Moon Hee; Kim, Eun Han; Hwang, Won Tae

1994-08-01

The thermal discharge used with cooling water at nuclear power plant is released to a neighbour sea and it is influenced on marine environment. The thermal discharge released from power plant is mainly transported and diffused by ocean circulation of neighbour sea. So the evaluation for characteristics of ocean circulation around neighbour sea is firstly performed. The purpose of this research is primarily analyzed the thermal diffusion in sea around Yongkwang nuclear power plant. For this viewpoint, fundamental oceanographic data sets are collected and analyzed in Yellow sea, west sea of Korea, sea around Yongkwang. The ocean circulation and the effects of temperature increase by thermal discharge are evaluated using these data. The characteristics of tide is interpreted by the analysis of observed tidal elevation and tidal currents. The characteristics of temperature and salinity is investigated by the long-term observation of Korea Fisheries Research and Development Agency and the short-term observation around Yongkwang. (Author)

Sandia Laboratories in-house activities in support of solar thermal large power applications

Science.gov (United States)

Mar, R. W.

1980-01-01

The development of thermal energy storage subsystems for solar thermal large power applications is described. The emphasis is on characterizing the behavior of molten nitrate salts with regard to thermal decomposition, environmental interactions, and corrosion. Electrochemical techniques to determine the ionic species in the melt and for use in real time studies of corrosion are also briefly discussed.

PowerLight Corporation Lean Manufacturing, PV Manufacturing R&D Phase I Report: 6 December 2001--31 March 2003

Energy Technology Data Exchange (ETDEWEB)

Hargis, L; Botkin, J.

2005-06-01

PowerLight Corporation (PowerLight) has completed Phase I of its PV Manufacturing R&D subcontract, ''PowerGuard Lean Manufacturing,'' Subcontract No. NDO-1-30628-04. The overall technical goal of this project was to reduce the cost of PowerGuard manufacturing while simultaneously improving product quality. This will enable PowerLight to scale up production capacity as the market for PowerGuard continues to grow. Through the introduction of world-class lean manufacturing techniques, PowerLight was to cut out waste in the manufacturing process of PowerGuard. The manufacturing process was to be overhauled with an objective of removing as much as possible those steps that do not add value to the product. Quality of finished goods was also to be improved through the use of statistical process control and error-proofing in the manufacturing process. Factory operations were also to be addressed to streamline those factory activities that support the manufacturing process. This report de tails the progress made toward the above listed goals during the first phase of this subcontract.

Validation of the thermal balance of Laguna Verde turbine under conditions of extended power increase

International Nuclear Information System (INIS)

Castaneda G, M. A.; Cruz B, H. J.; Mercado V, J. J.; Cardenas J, J. B.; Garcia de la C, F. M.

2012-10-01

The present work is a continuation of the task: Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt) in which the modeling of the vapor cycle of the nuclear power plant of Laguna Verde was realized with PEPSE code (Performance Evaluation of Power System Efficiencies). Once reached the conditions of nominal operation of extended power increase, operating both units to 2371 MWt; after the tests phase of starting-up and operation is necessary to carry out a verification of the proposed design of the vapor cycle for the new operation conditions. All this, having in consideration that the vapor cycle designer only knows the detail of the prospective performance of the main turbine, for all the other components (for example pumps, heat inter changers, valves, reactor, humidity separators and re-heaters, condensers, etc.) makes generic suppositions based on engineering judgment. This way carries out the calculations of thermal balance to determine the guaranteed gross power. The purpose of the present work is to comment the detail of the validation carried out of the specific thermal balance (thermal kit) of the nuclear power plant, making use of the design characteristics of the different components that conform the vapor cycle. (Author)

Theseus, the 50 MW solar thermal power plant; Das solarthermische 50-MW-Kraftwerk Theseus

Energy Technology Data Exchange (ETDEWEB)

Brakmann, G. [Fichtner GmbH und Co. KG, Stuttgart (Germany). Solarenergieprojekte

1998-04-01

The Isle of Crete measures 8331 km{sup 2}, and this island renowned for its historical sites attracts millions of tourists every year. Like any other branch of industry, tourism, which is called a ``white`` industry, has an ever growing demand for electric power. Up to now, electricity generation on the island is based on fossil-fuelled thermal power plants. However, recent developments indicate that this technology might be overtaken soon by the novel Theseus power plant (Thermal Solar European Power Station) currently under construction. It is expected to usher in a new era of power generation on the Isle of Crete. (orig./CB) [Deutsch] Die 8 331 km{sup 2} grosse Insel Kreta wurde vor ueber 3 500 Jahren besiedelt. Der geschichtstraechtige Ort ist ein hochgeschaetztes Reiseziel von Millionen Griechenlandurlaubern. Wie jede Art von Industrie, so benoetigt auch die als `weisse Industrie` bezeichnete Touristikbranche immer mehr elektrische Energie. Diese wird derzeit auf Kreta ausschliesslich mit thermischen Kraftwerken, welche fossile Brennstoffe verbrennen, erzeugt. Aber die Vorherrschaft dieser Technologie kann schon bald mit dem neuen solarthermischen Kraftwerk Theseus (Thermal Solar European Power Station) gebrochen werden. Es soll in wenigen Jahren eine neue Aera der Energieerzeugung auf Kreta einlaeuten. (orig.)

Portable low-power thermal cycler with dual thin-film Pt heaters for a polymeric PCR chip.

Science.gov (United States)

Jeong, Sangdo; Lim, Juhun; Kim, Mi-Young; Yeom, JiHye; Cho, Hyunmin; Lee, Hyunjung; Shin, Yong-Beom; Lee, Jong-Hyun

2018-01-29

Polymerase chain reaction (PCR) has been widely used for major definite diagnostic tool, but very limited its place used only indoor such as hospital or diagnosis lab. For the rapid on-site detection of pathogen in an outdoor environment, a low-power cordless polymerase chain reaction (PCR) thermal cycler is crucial module. At this point of view, we proposed a low-power PCR thermal cycler that could be operated in an outdoor anywhere. The disposable PCR chip was made of a polymeric (PI/PET) film to reduce the thermal mass. A dual arrangement of the Pt heaters, which were positioned on the top and bottom of the PCR chip, improved the temperature uniformity. The temperature sensor, which was made of the same material as the heater, utilized the temperature dependence of the Pt resistor to ensure simple fabrication of the temperature sensor. Cooling the PCR chip using dual blower fans enabled thermal cycling to operate with a lower power than that of a Peltier element with a high power consumption. The PCR components were electrically connected to a control module that could be operated with a Li-ion battery (12 V), and the PCR conditions (temperature, time, cycle, etc.) were inputted on a touch screen. For 30 PCR cycles, the accumulated power consumption of heating and cooling was 7.3 Wh, which is easily available from a compact battery. Escherichia coli genomic DNA (510 bp) was amplified using the proposed PCR thermal cycler and the disposable PCR chip. A similar DNA amplification capability was confirmed using the proposed portable and low-power thermal cycler compared with a conventional thermal cycler.

Hubungan Corporate Governance, Corporate Social Responsibilities dan Corporate Financial Performance Dalam Satu Continuum

Directory of Open Access Journals (Sweden)

Etty Murwaningsari

2009-01-01

Full Text Available This research aims to identify the influence of Good Corporate Governance, represented by institutional ownership and managerial ownership, on Corporate Social Responsibility and Corporate Financial Performance, and also to observe the possible influence of Corporate Social Responsibility on Corporate Financial Performance. This research examines 126 manufacturing companies which are listed in Indonesian Stock Exchange (ISX and have issued an audited financial statement for 2006. The statistical method used to test the hypothesis is Path Analysis. The result suggests that Good Corporate Governance influences both the disclosure of Corporate Social Responsibility and Corporate Financial Performance and that Corporate Social Responsibility significantly influences Corporate Financial Performance. The result also suggests that CEO Tenure, the controlling variable, holds a significant influence on the disclosure of Corporate Social Responsibility. Yet, there is no strong evidence to support the type of industries as an influencing factor of Corporate Social Responsibility. Furthermore, we found that the latter condition would also apply when we analyze the influence of Corporate Secretary and Nomination and Remuneration Committee on Corporate Financial Performance. Abstract in Bahasa Indonesia: Penelitian ini bertujuan untuk mengidentifikasi pengaruh antara struktur Coorporate Governance yang diproksikan sebagai kepemilikan institusional, kepemilikan manajerial terhadap corporate social responsibility dan corporate social responsibility terhadap corporate financial performance. Penelitian menggunakan data sekunder dari laporan tahunan 2006 perusahaan publik yang terdapat di Pusat Referensi Pasar Modal (PRPM Bursa Efek Indonesia (BEI. Sampel dalam penelitian ini sebanyak 126 perusahaan. Melalui pendekatan analisa jalur (path analysis menunjukkan Good Corporate Governance yaitu kepemilikan managerial dan institusional mempunyai pengaruh terhadap

Transient electro-thermal modeling of bipolar power semiconductor devices

CERN Document Server

Gachovska, Tanya Kirilova; Du, Bin

2013-01-01

This book presents physics-based electro-thermal models of bipolar power semiconductor devices including their packages, and describes their implementation in MATLAB and Simulink. It is a continuation of our first book Modeling of Bipolar Power Semiconductor Devices. The device electrical models are developed by subdividing the devices into different regions and the operations in each region, along with the interactions at the interfaces, are analyzed using the basic semiconductor physics equations that govern device behavior. The Fourier series solution is used to solve the ambipolar diffusio

A Case Study of Wind-PV-Thermal-Bundled AC/DC Power Transmission from a Weak AC Network

Science.gov (United States)

Xiao, H. W.; Du, W. J.; Wang, H. F.; Song, Y. T.; Wang, Q.; Ding, J.; Chen, D. Z.; Wei, W.

2017-05-01

Wind power generation and photovoltaic (PV) power generation bundled with the support by conventional thermal generation enables the generation controllable and more suitable for being sent over to remote load centre which are beneficial for the stability of weak sending end systems. Meanwhile, HVDC for long-distance power transmission is of many significant technique advantages. Hence the effects of wind-PV-thermal-bundled power transmission by AC/DC on power system have become an actively pursued research subject recently. Firstly, this paper introduces the technical merits and difficulties of wind-photovoltaic-thermal bundled power transmission by AC/DC systems in terms of meeting the requirement of large-scale renewable power transmission. Secondly, a system model which contains a weak wind-PV-thermal-bundled sending end system and a receiving end system in together with a parallel AC/DC interconnection transmission system is established. Finally, the significant impacts of several factors which includes the power transmission ratio between the DC and AC line, the distance between the sending end system and receiving end system, the penetration rate of wind power and the sending end system structure on system stability are studied.

Large scale solar thermal power for the European Union{exclamation_point}

Energy Technology Data Exchange (ETDEWEB)

Anon.

1997-06-01

Southern Europe, on the edge of the sunbelt, represents the ideal location for solar thermal generated power. Last year. SAWIE reported on the THESEUS project, a proposed 50 MWe solar thermal power plant for Frangokastello, southern Crete, which was submitted for support under the European Union`s THERMIE Programme. Funding was approved for the design phase for this innovative power plant, the first large-scale SEGS-style plant on European soil, at the end of last year. However, the THERMIE Programme also provided support for another Southern European plant, proposed by Colon Solar for Huelva in Southern Spain. Whilst hurdles remain to be overcome before both plants are built and commissioned, there is an excellent chance that by the start of the new Millennium, the solar collectors from these two plants could be generating over half a million MWh of energy a year. SAWIE compares the two projects. (author)

Corporate Law and Corporate Governance

OpenAIRE

Roberta Romano

1998-01-01

We have seen a revival in interest in corporate law and corporate governance since the 1980s, as researchers applied the tools of the new institutional economics and modern corporate finance to analyze the new transactions emerging in the 1980s takeover wave. This article focuses on three mechanisms of corporate governance to illustrate the analytical usefulness of transaction cost economics for corporate law. They are the board of directors; relational investing, a form of block ownership in...

76 FR 73608 - Reliability Technical Conference, North American Electric Reliability Corporation, Public Service...

Science.gov (United States)

2011-11-29

... or municipal authority play in forming your bulk power system reliability plans? b. Do you support..., North American Electric Reliability Corporation (NERC) Nick Akins, CEO of American Electric Power (AEP..., EL11-62-000] Reliability Technical Conference, North American Electric Reliability Corporation, Public...

Control during corporate crisis: asbestos and the Manville bankruptcy.

Science.gov (United States)

Delaney, K J

1991-01-01

Chapter 11 bankruptcy provides an opportunity for addressing issues of power and control during corporate crisis. A broad notion of power is essential in understanding the complex events that led to the Chapter 11 filing of the Manville Corporation, formerly the nation's leading asbestos manufacturer. The theory of finance hegemony places this case in an entirely new light by taking into account the power of the financial community. The Manville bankruptcy illuminates several mechanisms by which this hegemony operates. From this perspective, Chapter 11 bankruptcy is viewed as a choice made from a set of options severely constrained by other powerful institutions, rather than a result of managerial incompetence or market failure.

Human power output during repeated sprint cycle exercise: the influence of thermal stress

NARCIS (Netherlands)

Ball, D.; Burrows, C.; Sargeant, A.J.

1999-01-01

Thermal stress is known to impair endurance capacity during moderate prolonged exercise. However, there is relatively little available information concerning the effects of thermal stress on the performance of high-intensity short-duration exercise. The present experiment examined human power output

A critical review on energy, exergy, exergoeconomic and economic (4-E analysis of thermal power plants

Directory of Open Access Journals (Sweden)

Ravinder Kumar

2017-02-01

Full Text Available The growing energy supply, demand has created an interest towards the plant equipment efficiency and the optimization of existing thermal power plants. Also, a thermal power plant dependency on fossil fuel makes it a little bit difficult, because of environmental impacts has been always taken into consideration. At present, most of the power plants are going to be designed by the energetic performance criterion which is based on the first law of thermodynamics. Sometimes, the system energy balance is not sufficient for the possible finding of the system imperfections. Energy losses taking place in a system can be easily determined by using exergy analysis. Hence, it is a powerful tool for the measurement of energy quality, thereby helps to make complex thermodynamic systems more efficient. Nowadays, economic optimization of plant is also a big problem for researchers because of the complex nature. At a viewpoint of this, a comprehensive literature review over the years of energy, exergy, exergoeconomic and economic (4-E analysis and their applications in thermal power plants stimulated by coal, gas, combined cycle and cogeneration system have been done thoroughly. This paper is addressed to those researchers who are doing their research work on 4-E analysis in various thermal power plants. If anyone extracts an idea for the development of the concept of 4-E analysis using this article, we will achieve our goal. This review also indicates the scope of future research in thermal power plants.

Optimum voltage of auxiliary systems for thermal and nuclear power plants

International Nuclear Information System (INIS)

Tokumitsu, Iwao; Segawa, Motomichi

1979-01-01

In the power plants in Japan, their unit power output has been greatly enhanced since the introduction of new powerful thermal power plants from 1950's to 1960's. In both thermal and nuclear power plants, 1,000 MW machines have been already in operation. The increase of unit power output results in the increase of in-plant load capacity. Of these the voltage adopted for in-plant low voltage systems is now mainly 440 V at load terminals, and the voltage for in-plant high voltage systems has been changing to 6 kV level via 3 kV and 4 kV levels. As plant capacity increases, the load of low voltage systems significantly increases, and it is required to raise the voltage of 400 V level. By the way, the low voltage in AC is specified to be not higher than 600 V. This makes the change within the above range comparatively easy. Considering these conditions, it is recommended to change the voltage for low voltage systems to 575 V at power source terminals and 550 V at load terminals. Some merits in constructing power systems and in economy by raising the voltage were examined. Though demerits are also found, they are only about 15% of total merits. The most advantageous point in raising the voltage is to be capable of increasing the supplying range to low voltage system loads. (Wakatsuki, Y.)

Optimization of thermal efficiency of nuclear central power like as PWR

International Nuclear Information System (INIS)

Lapa, Nelbia da Silva

2005-10-01

The main purpose of this work is the definition of operational conditions for the steam and power conservation of Pressurized Water Reactor (PWR) plant in order to increase its system thermal efficiency without changing any component, based on the optimization of operational parameters of the plant. The thermal efficiency is calculated by a thermal balance program, based on conservation equations for homogeneous modeling. The circuit coefficients are estimated by an optimization tool, allowing a more realistic thermal balance for the plans under analysis, as well as others parameters necessary to some component models. With the operational parameter optimization, it is possible to get a level of thermal efficiency that increase capital gain, due to a better relationship between the electricity production and the amount of fuel used, without any need to change components plant. (author)

Power Electronics Thermal Management R&D; NREL (National Renewable Energy Laboratory)

Energy Technology Data Exchange (ETDEWEB)

Waye, Scot

2015-06-10

Presentation containing an update for the Power Electronics Thermal Management project in the Electric Drive Train task funded by the Vehicle Technology Office of DOE. This presentation outlines the purpose, plan, and results of research thus far for cooling and material selection strategies to manage heat in power electronic assemblies such as inverters, converters, and chargers.

Subsidiary Power in Multinational Corporations

DEFF Research Database (Denmark)

Dörrenbächer, Christoph; Gammelgaard, Jens

2011-01-01

Purpose – As subsidiary power has received relatively little attention in existing research, this paper aims to enhance the understanding of genuine sources of subsidiary power and how they work in headquarters-subsidiary relationships. Design/methodology/approach – The paper is based on a review...... of the relevant literature and four illustrative case studies, which are written on the basis of secondary sources. Each case was selected because it adequately represents a particular type of power. This allows for cross-case comparisons of the strengths and sustainability of different types of power......, and facilitates the exploration of the application of subsidiary power in headquarters-subsidiary relationships. Findings – Four genuine types of subsidiary power are identified. One of these – micro-political bargaining power – plays a subtle but crucial role, as it is important in the enactment of the three...

Power electronics solution to dust emissions from thermal power plants

Directory of Open Access Journals (Sweden)

Vukosavić Slobodan

2010-01-01

Full Text Available Thermal power stations emit significant amounts of fly ash and ultra fine particles into the atmosphere. Electrostatic precipitators (ESP or electro filters remove flying ashes and fine particles from the flue gas before passing the gas into the chimney. Maximum allowable value of dust is 50 mg/m3 and it requires that the efficiency of the ESPs better than 99 %, which calls for an increase of active surface of the electrodes, hence increasing the filter volume and the weight of steel used for the filter. In previous decades, electrostatic precipitators in thermal power plants were fed by thyristor controlled, single phase fed devices having a high degree of reliability, but with a relatively low collection efficiency, hence requiring large effective surface of the collection plates and a large weight of steel construction in order to achieve the prescribed emission limits. Collection efficiency and energy efficiency of the electrostatic precipitator can be increased by applying high frequency high voltage power supply (HF HV. Electrical engineering faculty of the University of Belgrade (ETF has developed technology and HF HV equipment for the ESP power supply. This solution was subjected to extensive experimental investigation at TE Morava from 2008 to 2010. High frequency power supply is proven to reduce emission two times in controlled conditions while increasing energy efficiency of the precipitator, compared to the conventional thyristor controlled 50Hz supply. Two high frequency high voltage unit AR70/1000 with parameters 70 kV and 1000 mA are installed at TE Morava and thoroughly testes. It was found that the HF HV power supply of the ESP at TE Morava increases collection efficiency so that emission of fine particles and flying ashes are halved, brought down to only 50 % of the emissions encountered with conventional 50 Hz thyristor driven power supplies. On the basis of this study, conclusion is drawn that the equipment comprising HF HV

Cooling problems of thermal power plants. Physical model studies

International Nuclear Information System (INIS)

Neale, L.C.

1975-01-01

The Alden Research Laboratories of Worcester Polytechnic Institute has for many years conducted physical model studies, which are normally classified as river or structural hydraulic studies. Since 1952 one aspect of these studies has involved the heated discharge from steam power plants. The early studies on such problems concentrated on improving the thermal efficiency of the system. This was accomplished by minimizing recirculation and by assuring full use of available cold water supplies. With the growing awareness of the impact of thermal power generation on the environment attention has been redirected to reducing the effect of heated discharges on the biology of the receiving body of water. More specifically the efforts of designers and operators of power plants are aimed at meeting or complying with standards established by various governmental agencies. Thus the studies involve developing means of minimizing surface temperatures at an outfall or establishing a local area of higher temperature with limits specified in terms of areas or distances. The physical models used for these studies have varied widely in scope, size, and operating features. These models have covered large areas with both distorted geometric scales and uniform dimensions. Instrumentations has also varied from simple mercury thermometers to computer control and processing of hundreds of thermocouple indicators

Managing Corporate Reputation Through Corporate Branding

DEFF Research Database (Denmark)

Schultz, Majken; Hatch, Mary Jo; Adams, Nick

2012-01-01

This article, which concentrates on symbolic management by explaining the role of corporate branding in managing corporate reputation, using Novo Nordisk as a case study, presents three perspectives on corporate branding: the marketing perspective, the organisational perspective and the co...... is a way to influence corporate reputation. The Novo Nordisk management believes the data indicate that corporate branding influenced reputation more than the other way around. Formal brand management practices may work considerably better when they complement rather than try to control existing forces......-creation perspective. The three perspectives reviewed show the possibility of developing a multidisciplinary conceptualisation of corporate branding. They all offer insights important to managing organisations as corporate brands in a multi-stakeholder context and thus to the likelihood that corporate branding...

Performance analysis of different ORC configurations for thermal energy and LNG cold energy hybrid power generation system

Science.gov (United States)

Sun, Zhixin; Wang, Feng; Wang, Shujia; Xu, Fuquan; Lin, Kui

2017-01-01

This paper presents a thermal energy and Liquefied natural gas (LNG) cold energy hybrid power generation system. Performances of four different Organic Rankine cycle (ORC) configurations (the basic, the regenerative, the reheat and the regenerative-reheat ORCs) are studied based on the first and the second law of thermodynamics. Dry organic fluid R245fa is selected as the typical working fluid. Parameter analysis is also conducted in this paper. The results show that regeneration could not increase the thermal efficiency of the thermal and cold energy hybrid power generation system. ORC with the reheat process could produce more specific net power output but it may also reduce the system thermal efficiency. The basic and the regenerative ORCs produce higher thermal efficiency while the regenerative-reheat ORC performs best in the exergy efficiency. A preheater is necessary for the thermal and cold energy hybrid power generation system. And due to the presence of the preheater, there will be a step change of the system performance as the turbine inlet pressure rises.

Valves for condenser-cooling-water circulating piping in thermal power station and nuclear power station

International Nuclear Information System (INIS)

Kondo, Sumio

1977-01-01

Sea water is mostly used as condenser cooling water in thermal and nuclear power stations in Japan. The quantity of cooling water is 6 to 7 t/sec per 100,000 kW output in nuclear power stations, and 3 to 4 t/sec in thermal power stations. The pipe diameter is 900 to 2,700 mm for the power output of 75,000 to 1,100,000 kW. The valves used are mostly butterfly valves, and the reliability, economy and maintainability must be examined sufficiently because of their important role. The construction, number and arrangement of the valves around a condenser are different according to the types of a turbine and the condenser and reverse flow washing method. Three types are illustrated. The valves for sea water are subjected to the electrochemical corrosion due to sea water, the local corrosion due to stagnant water, the fouling by marine organisms, the cavitation due to valve operation, and the erosion by earth and sand. The fundamental construction, use and features of butterfly valves are described. The cases of the failure and repair of the valves after their delivery are shown, and they are the corrosion of valve bodies and valve seats, and the separation of coating and lining. The newly developed butterfly valve with overall water-tight rubber lining is introduced. (Kako, I.)

Thermal Simulation of Switching Pulses in an Insulated Gate Bipolar Transistor (IGBT) Power Module

Science.gov (United States)

2015-02-01

executed with SolidWorks Flow Simulation , a computational fluid-dynamics code. The graph in Fig. 2 shows the timing and amplitudes of power pulses...defined a convective flow of air perpendicular to the bottom surface of the mounting plate, with a velocity of 10 ft/s. The thermal simulations were...Thermal Simulation of Switching Pulses in an Insulated Gate Bipolar Transistor (IGBT) Power Module by Gregory K Ovrebo ARL-TR-7210

Prognostics Approach for Power MOSFET Under Thermal-Stress

Science.gov (United States)

Galvan, Jose Ramon Celaya; Saxena, Abhinav; Kulkarni, Chetan S.; Saha, Sankalita; Goebel, Kai

2012-01-01

The prognostic technique for a power MOSFET presented in this paper is based on accelerated aging of MOSFET IRF520Npbf in a TO-220 package. The methodology utilizes thermal and power cycling to accelerate the life of the devices. The major failure mechanism for the stress conditions is dieattachment degradation, typical for discrete devices with leadfree solder die attachment. It has been determined that dieattach degradation results in an increase in ON-state resistance due to its dependence on junction temperature. Increasing resistance, thus, can be used as a precursor of failure for the die-attach failure mechanism under thermal stress. A feature based on normalized ON-resistance is computed from in-situ measurements of the electro-thermal response. An Extended Kalman filter is used as a model-based prognostics techniques based on the Bayesian tracking framework. The proposed prognostics technique reports on preliminary work that serves as a case study on the prediction of remaining life of power MOSFETs and builds upon the work presented in [1]. The algorithm considered in this study had been used as prognostics algorithm in different applications and is regarded as suitable candidate for component level prognostics. This work attempts to further the validation of such algorithm by presenting it with real degradation data including measurements from real sensors, which include all the complications (noise, bias, etc.) that are regularly not captured on simulated degradation data. The algorithm is developed and tested on the accelerated aging test timescale. In real world operation, the timescale of the degradation process and therefore the RUL predictions will be considerable larger. It is hypothesized that even though the timescale will be larger, it remains constant through the degradation process and the algorithm and model would still apply under the slower degradation process. By using accelerated aging data with actual device measurements and real

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

Nickel hydrogen and silver zinc battery cell modeling at the Aerospace Corporation

Energy Technology Data Exchange (ETDEWEB)

Zimmerman, A.H.

1996-02-01

A nickel hydrogen battery cell model has been fully developed and implemented at The Aerospace Corporation. Applications of this model to industry needs for the design of better cells, power system design and charge control thermal management, and long-term performance trends will be described. Present efforts will be described that are introducing the silver and zinc electrode reactions into this model architecture, so that the model will be able to predict performance for not only silver zinc cells, but also nickel zinc, silver hydrogen, and silver cadmium cells. The silver zinc cell modeling effort is specifically designed to address the concerns that arise most often in launch vehicle applications: transient response, power-on voltage regulation, hot or cold operation, electrolyte spewing, gas venting, self-discharge, separator oxidation, and oxalate crystal growth. The specific model features that are being employed to address these issues will be described.

Energy audit: thermal power, combined cycle, and cogeneration plants

Energy Technology Data Exchange (ETDEWEB)

Abbi, Yash Pal

2012-07-01

The availability of fossil fuels required for power plants is reducing and their costs increasing rapidly. This gives rise to increase in the cost of generation of electricity. But electricity regulators have to control the price of electricity so that consumers are not stressed with high costs. In addition, environmental considerations are forcing power plants to reduce CO2 emissions. Under these circumstances, power plants are constantly under pressure to improve the efficiency of operating plants, and to reduce fuel consumption. In order to progress in this direction, it is important that power plants regularly audit their energy use in terms of the operating plant heat rate and auxiliary power consumption. The author attempts to refresh the fundamentals of the science and engineering of thermal power plants, establish its link with the real power plant performance data through case studies, and further develop techno-economics of the energy efficiency improvement measures. This book will rekindle interest in energy audits and analysis of the data for designing and implementation of energy conservation measures on a continuous basis.

Statistical modeling of an integrated boiler for coal fired thermal power plant.

Science.gov (United States)

Chandrasekharan, Sreepradha; Panda, Rames Chandra; Swaminathan, Bhuvaneswari Natrajan

2017-06-01

The coal fired thermal power plants plays major role in the power production in the world as they are available in abundance. Many of the existing power plants are based on the subcritical technology which can produce power with the efficiency of around 33%. But the newer plants are built on either supercritical or ultra-supercritical technology whose efficiency can be up to 50%. Main objective of the work is to enhance the efficiency of the existing subcritical power plants to compensate for the increasing demand. For achieving the objective, the statistical modeling of the boiler units such as economizer, drum and the superheater are initially carried out. The effectiveness of the developed models is tested using analysis methods like R 2 analysis and ANOVA (Analysis of Variance). The dependability of the process variable (temperature) on different manipulated variables is analyzed in the paper. Validations of the model are provided with their error analysis. Response surface methodology (RSM) supported by DOE (design of experiments) are implemented to optimize the operating parameters. Individual models along with the integrated model are used to study and design the predictive control of the coal-fired thermal power plant.

Choosing Actuators for Automatic Control Systems of Thermal Power Plants

Energy Technology Data Exchange (ETDEWEB)

Gorbunov, A. I., E-mail: gor@tornado.nsk.ru [JSC “Tornado Modular Systems” (Russian Federation); Serdyukov, O. V. [Siberian Branch of the Russian Academy of Sciences, Institute of Automation and Electrometry (Russian Federation)

2015-03-15

Two types of actuators for automatic control systems of thermal power plants are analyzed: (i) pulse-controlled actuator and (ii) analog-controlled actuator with positioning function. The actuators are compared in terms of control circuit, control accuracy, reliability, and cost.

Thermal performance test for steam turbine of nuclear power plants

International Nuclear Information System (INIS)

Bu Yubing; Xu Zongfu; Wang Shiyong

2014-01-01

Through study of steam turbine thermal performance test of CPR1000 nuclear power plant, we solve the enthalpy calculation problems of the steam turbine in wet steam zone using heat balance method which can help to figure out the real overall heat balance diagram for the first time, and we develop a useful software for thermal heat balance calculation. Ling'ao phase II as an example, this paper includes test instrument layout, system isolation, risk control, data acquisition, wetness measurement, heat balance calculation, etc. (authors)

A new method for evaluation and correction of thermal reactor power and present operational applications

International Nuclear Information System (INIS)

Langenstein, M.; Streit, S.; Laipple, B.; Eitschberger, H.

2005-01-01

The determination of the thermal reactor power is traditionally be done by heat balance: 1) for a boiling water reactor (BWR) at the interface of reactor control volume and heat cycle. 2) for a pressurised-water reactor (PWR) at the interface of the steam generator control volume and turbine island on the secondary side. The uncertainty of these traditional methods is not easy to determine and can be in the range of several percent. Technical and legal regulations (e.g. 10CFR50) cover an estimated error of instrumentation up to 2% by increasing the design thermal reactor power for emergency analysis to 102 % of the licensed thermal reactor power. Basically the licensee has the duty to warrant at any time operation inside the analyzed region for thermal reactor power. This is normally done by keeping the indicated reactor power at the licensed 100% value. The better way is to use a method which allows a continuous warranty evaluation. The quantification of the level of fulfilment of this warranty is only achievable by a method which: 1) is independent of single measurements accuracies. 2) results in a certified quality of single process values and for the total heat cycle analysis. 3)leads to complete results including 2-sigma deviation especially for thermal reactor power. Here this method, which is called 'process data reconciliation based on VDI 2048 guideline', is presented [1, 2]. This method allows to determine the true process parameters with a statistical probability of 95%, by considering closed material, mass- and energy balances following the Gaussian correction principle. The amount of redundant process information and complexity of the process improves the final results. This represents the most probable state of the process with minimized uncertainty according to VDI 2048. Hence, calibration and control of the thermal reactor power are possible with low effort but high accuracy and independent of single measurement accuracies. Further more, VDI 2048

Analyses of thermal plume of Cernavoda nuclear power plant by satellite remote sensing data

Science.gov (United States)

Zoran, M. A.; Nicolae, D. N.; Talianu, C. L.; Ciobanu, M.; Ciuciu, J. G.

2005-10-01

The synergistic use of multi-temporal and multi-spectral remote sensing data offers the possibility of monitoring of environment quality in the vicinity of nuclear power plants (NPP). Advanced digital processing techniques applied to several LANDSAT, MODIS and ASTER data are used to assess the extent and magnitude of radiation and non-radiation effects on the water, near field soil, vegetation and air for NPP Cernavoda , Romania . Cernavoda Unit 1 power plant, using CANDU technology, having 706.5 MW power, is successfully in operation since 1996. Cernavoda Unit 2 which is currently under construction will be operational in 2007. Thermal discharge from nuclear reactor cooling is dissipated as waste heat in Danube-Black -Sea Canal and Danube river. Water temperature distributions captured in thermal IR imagery are correlated with meteorological parameters. Additional information regarding flooding events and earthquake risks is considered . During the winter, the thermal plume is localized to an area within a few km of the power plant, and the temperature difference between the plume and non-plume areas is about 1.5 oC. During the summer and fall, there is a larger thermal plume extending 5-6 km far along Danube Black Sea Canal, and the temperature change is about 1.0 oC. Variation of surface water temperature in the thermal plume is analyzed. The strong seasonal difference in the thermal plume is related to vertical mixing of the water column in winter and to stratification in summer. Hydrodynamic simulation leads to better understanding of the mechanisms by which waste heat from NPP Cernavoda is dissipated in the environment.

Thermal Management of Transient Power Spikes in Electronics - Phase Change Energy Storage or Copper Heat Sinks?

OpenAIRE

Krishnan, S.; Garimella, S V

2004-01-01

A transient thermal analysis is performed to investigate thermal control of power semiconductors using phase change materials, and to compare the performance of this approach to that of copper heat sinks. Both the melting of the phase change material under a transient power spike input, as well as the resolidification process, are considered. Phase change materials of different kinds (paraffin waxes and metallic alloys) are considered, with and without the use of thermal conductivity enhancer...

Supplier selection criteria for sustainable supply chain management in thermal power plant

Science.gov (United States)

Firoz, Faisal; Narayan Biswal, Jitendra; Satapathy, Suchismita

2018-02-01

Supplies are always in great demand when it comes to industrial operations. The quality of raw material their price accompanied by sustainability and environmental effects are a major concern for industrial operators these days. Supply Chain Management is the subject which is focused on how the supply of different products is carried out. The motive is that each operation performed can be optimized and inherently the efficiency of the whole chain is integrated. In this paper we will be dealing with all the criteria that are required to be evaluated before selecting a supplier, in particular, focusing on Thermal Power Plant. The most suppliers of the thermal power plant are the coal suppliers. The quality of coal directly determines the efficiency of the whole plant. And when there are matters concerning coal environmental pollution plays a very crucial role. ANP method has been used here to select suppliers of thermal power sectors in Indian context. After applying ANP to prioritize the sustainable supplier selection criteria, it is found that for thermal power industries best suppliers are Nationalized/State owned suppliers then 2nd ranked suppliers are imported supplier. Private owned suppliers are ranked least. So private owned suppliers must be more concerned about their performance. Among these suppliers it is found that to compete in the global market privatized suppliers have to give more emphasize on most important criteria like sustainability, then fuel cost and quality. Still some sub-criteria like a clean program, environmental issues, quality, reliability, service rate, investment in high technology, green transportation channel, waste management etc needs for continuous improvement as per their priority.

Thermal power calibration of the TRIGA Mark I IPR-R1 reactor during the upgrading tests to 250 kW

International Nuclear Information System (INIS)

Mesquita, Amir Zacarias; Maretti, Fausto Junior; Rezende, Hugo Cesar

2002-01-01

This paper presents the results and the methodology used to calibrate the thermal power of the TRIGA MARK I IPR-R1 Reactor in CDTN, Belo Horizonte, Brazil. This calibration was realized during the operation tests carried out to allow the reactor power upgrade from the current 100 kW to 250 kW. The methodology consisted in the measurement of the inlet and outlet temperature and the water flow in the primary cooling loop. The thermal balance together with the thermal losses gave the thermal power. There were made three sequences of tests. The first rising of the thermal power was made with the usual configuration of the core (59 fuel elements). After the changing of the ion chambers position and the control rod and the increase of the number of fuels (63 fuel elements), a new evaluation of the thermal power was accomplished, having been obtained a thermal power of 234 kW, for an indication of 250 kW in the lineal channel. After the return of the core to the initial configuration (59 fuel elements), it took place a new test, getting back the reactor to the power level of 100 kW. (author)

Application of pulsed power and power modulation to the non-thermal plasma treatment of hazardous gaseous wastes

International Nuclear Information System (INIS)

Penetrante, B.M.

1992-10-01

Acid rain, global warming, ozone depletion, and smog are preeminent environmental problems facing the world today. Non-thermal plasma techniques offer an innovative approach to the cost-effective solution of these problems. Many potential applications of non-thermal plasmas to air pollution control have already been demonstrated. The use of pulsed power and power modulation is essential to the successful implementation of non-thermal plasma techniques. This paper provides an overview of the most recent developments in non-thermal plasma systems that have been applied to gaseous waste treatment. In the non-thermal plasma approach, the nonequilibrium properties of the plasma are fully exploited. These plasmas are characterized by high electron temperatures, while the gas remains at near ambient temperature and pressure. The energy is directed preferentially to the undesirable components, which are often present in very small concentrations. These techniques utilize the dissociation and ionization of the background gas to produce radicals which, in turn, decompose the toxic compounds. The key to success in the non-thermal plasma approach is to produce a discharge in which the majority of the electrical energy goes into the production of energetic electrons, rather than into gas heating. For example, in a typical application to flue gas cleanup, these electrons produce radicals, such as O and OH, through the dissociation or ionization of molecules such as H 2 O or O 2 . The radicals diffuse through the gas and preferentially oxidize the nitrogen oxides and sulfur oxides to form acids that can then be easily neutralized to form non-toxic, easily-collectible (and commercially salable) compounds. Non-thermal plasmas can be created in essentially two different ways: by electron-beam irradiation, and by electrical discharges

Emission Control Technologies for Thermal Power Plants

Science.gov (United States)

Nihalani, S. A.; Mishra, Y.; Juremalani, J.

2018-03-01

Coal thermal power plants are one of the primary sources of artificial air emissions, particularly in a country like India. Ministry of Environment and Forests has proposed draft regulation for emission standards in coal-fired power plants. This includes significant reduction in sulphur-dioxide, oxides of nitrogen, particulate matter and mercury emissions. The first step is to evaluate the technologies which represent the best selection for each power plant based on its configuration, fuel properties, performance requirements, and other site-specific factors. This paper will describe various technology options including: Flue Gas Desulfurization System, Spray Dryer Absorber (SDA), Circulating Dry Scrubber (CDS), Limestone-based Wet FGD, Low NOX burners, Selective Non Catalytic Reduction, Electrostatic Precipitator, Bag House Dust Collector, all of which have been evaluated and installed extensively to reduce SO2, NOx, PM and other emissions. Each control technology has its advantages and disadvantages. For each of the technologies considered, major features, potential operating and maintenance cost impacts, as well as key factors that contribute to the selection of one technology over another are discussed here.

Corporate brand positioning : searching for a new position - case Metso Power

OpenAIRE

KUURU, TIINA-KAISA

2013-01-01

Tutkielmasta TamPubissa rajattu versio. Täydellinen versio luettavissa Tampereen yliopiston Linna-kirjastossa. This is a limited version of the Master's thesis. The complete version can be viewed in print at Tampere University Library The purpose of this study is to describe and analyse the process of corporate brand positioning. Study is focused on B2B market, precisely on industrial brands. Corporate brand positioning is defined as a process of searching and finding a...

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.

Modelling and Design of Active Thermal Controls for Power Electronics of Motor Drive Applications

DEFF Research Database (Denmark)

Vernica, Ionut; Blaabjerg, Frede; Ma, Ke

2017-01-01

of active thermal control methods for the power devices of a motor drive application. The motor drive system together with the thermal cycling of the power devices have been modelled, and adverse temperature swings could be noticed during the start-up and deceleration periods of the motor. Based...... on the electrical response of the system, the junction temperature of the semiconductor devices is estimated, and consequently three active thermal control methods are proposed and practically designed with respect to the following parameters: switching frequency, deceleration slope and modulation technique....... Finally, experimental results are provided in order to validate the effectiveness of the proposed control methods....

Trends in HPC and Data Center Power, Packaging, and Cooling

CERN Multimedia

CERN. Geneva

2016-01-01

air vs liquid-cooling, and metrics to track it all will be discussed. About the speaker Michael K. Patterson is a Senior Principal Engineer in the Technical Computing Group - Systems Architecture & Pathfinding at the Intel Corporation, in Dupont, Washington, where he works in the power, thermal, and energy-efficient-performance areas of High Performance Computing. The work covers silicon level activity, through platform and rack-level solutions, and on up to interface with Data Center power and cooling technologies. He did his undergraduate work at Purdue University, received his MS degree in Management from Rensselaer Polytechnic Institute, an...

Thermal design of a modern, air-conditioned, single-floor, solar-powered desert house

KAUST Repository

Serag-Eldin, M. A.

2011-01-01

The paper presents a thermal analysis of a single-floor, solar-powered desert house. The house is air-conditioned and provides all modern comforts and facilities. Electrical power, which drives the entire energy system, is generated by roof

Physico-chemical characterization of slag waste coming from GICC thermal power plant

Energy Technology Data Exchange (ETDEWEB)

Acosta, A.; Aineto, M.; Iglesias, I. [Laboratory of Applied Mineralogy, Universidad de Castilla-La Mancha, Ciudad Real Madrid (Spain); Romero, M.; Rincon, J.Ma. [The Glass-Ceramics Laboratory, Insituto Eduardo Torroja de Ciencias de la Construccion, CSIC, c/Serrano Galvache s/n, 28033, Madrid (Spain)

2001-09-01

The new gas installations of combined cycle (GICC) thermal power plants for production of electricity are more efficient than conventional thermal power plants, but they produce a high quantity of wastes in the form of slags and fly ashes. Nowadays, these by-products are stored within the production plants with, until now, no applications of recycling in other industrial processes. In order to evaluate the capability of these products for recycling in glass and ceramics inductory, an investigation for the full characterization has been made by usual physico-chemical methods such as: chemical analysis, mineralogical analysis by XRD, granulometry, BET, DTA/TG, heating microscopy and SEM/EDX.

Thermal optimization of the helium-cooled power leads for the SSC

International Nuclear Information System (INIS)

Demko, J.A.; Schiesser, W.E.; Carcagno, R.; McAshan, M.; McConeghy, R.

1992-03-01

The optimum thermal design of the power leads for the Superconducting Super Collider (SSC) will minimize the amount of Carnot work (which is a combination of refrigeration and liquefaction work) required. This optimization can be accomplished by the judicious selection of lead length and diameter. Even though an optimum set of dimensions is found, the final design must satisfy other physical constraints such as maximum allowable heat leak and helium vapor mass flow rate. A set of corresponding lengths and diameters has been determined that meets these requirements for the helium vapor-cooled, spiral-fin power lead design of the SSC. Early efforts by McFee and Mallon investigated optimizing power leads for cryogenic applications with no convection cooling. Later designs utilized the boiled-off helium vapor to cool the lead. One notable design for currents up to several thousand amps is presented by Efferson based on a series of recommendations discussed by Deiness. Buyanov presents many theoretical models and design formulate but does not demonstrate an approach to thermally optimizing the design of a vapor-cooled lead. A method for optimizing superconducting magnet current leads is described by Maehata et al. The approach assumes that the helium boil-off caused by heat conduction along with power lead into the low-temperature helium is used to cool the lead. The optimum solution is found when the heat flow at the cold end is minimized.. In this study, a detailed numerical thermal model of a power lead design for the SSC has been developed. It was adapted from the dynamic model developed by Schiesser. This model was used to determine the optimum dimensions that minimize the Carnot refrigeration and liquefaction work due to the leads

Analyzing Thermal Module Developments and Trends in High-Power LED

Directory of Open Access Journals (Sweden)

Jung-Chang Wang

2014-01-01

Full Text Available The solid-state light emitting diode (SSLED has been verified as consumer-electronic products and attracts attention to indoor and outdoor lighting lamp, which has a great benefit in saving energy and environmental protection. However, LED junction temperature will influence the luminous efficiency, spectral color, life cycle, and stability. This study utilizes thermal performance experiments with the illumination-analysis method and window program (vapour chamber thermal module, VCTM V1.0 to investigate and analyze the high-power LED (Hi-LED lighting thermal module, in order to achieve the best solution of the fin parameters under the natural convection. The computing core of the VCTM program employs the theoretical thermal resistance analytical approach with iterative convergence stated in this study to obtain a numerical solution. Results showed that the best geometry of thermal module is 4.4 mm fin thickness, 9.4 mm fin pitch, and 37 mm fin height with the LED junction temperature of 58.8°C. And the experimental thermal resistances are in good agreement with the theoretical thermal resistances; calculating error between measured data and simulation results is no more than ±7%. Thus, the Hi-LED illumination lamp has high life cycle and reliability.

An analysis of factors that influence the technical efficiency of Malaysian thermal power plants

International Nuclear Information System (INIS)

See, Kok Fong; Coelli, Tim

2012-01-01

The main objectives of this paper are to measure the technical efficiency levels of Malaysian thermal power plants and to investigate the degree to which various factors influence efficiency levels in these plants. Stochastic frontier analysis (SFA) methods are applied to plant-level data over an eight year period from 1998 to 2005. This is the first comprehensive analysis (to our knowledge) of technical efficiency in the Malaysian electricity generation industry using parametric method. Our empirical results indicate that ownership, plant size and fuel type have a significant influence on technical efficiency levels. We find that publicly-owned power plants obtain average technical efficiencies of 0.68, which is lower than privately-owned power plants, which achieve average technical efficiencies of 0.88. We also observe that larger power plants with more capacity and gas-fired power plants tend to be more technically efficient than other power plants. Finally, we find that plant age and peaking plant type have no statistically significant influence on the technical efficiencies of Malaysian thermal power plants. - Highlights: ► We examine the technical efficiency (TE) levels of Malaysian thermal power plants. ► We also investigate the degree to which various factors influence efficiency levels in these plants. ► Stochastic frontier analysis methods are used. ► Average plant would have to increase their TE level by 21% to reach the efficient frontier. ► Ownership, plant size and fuel type have a significant influence on the TE levels.

Operation management of thermal power plant. Karyoku plant no unten kanri

Energy Technology Data Exchange (ETDEWEB)

1994-06-15

Nowadays, thermal power plants are getting bigger and bigger in capacity. At the same time, high reliability to the frequent start and stop due to the demand change as well as effective economy. This paper describes the total operation management system. It included the start and stop, normal operation, specified operation, water quality, operation management involving the environmental problems, protection of machinery and equipment in case of emergency, measures against the failure, and the measures against the disaster. The outline of the normal operation is as follows: from the cost economical point of view, the kind of fuel is changed according to the load; i.e., coal for basic operation, LNG for basic to medium operation, and oil for medium to peak operation. The change in demand cannot be followed by the hydroelectric power. The adjustment of the power depending on the load change can be achieved by the thermal power generation. The automatic frequency control, economical load distribution control are also done. In the nighttime, the minimum load operation is required. The voltage change operation below the rated value or the phase-advancing operation is also done depending on the load conditions. 21 figs., 6 tabs.

Simulation study of multi-step model algorithmic control of the nuclear reactor thermal power tracking system

International Nuclear Information System (INIS)

Shi Xiaoping; Xu Tianshu

2001-01-01

The classical control method is usually hard to ensure the thermal power tracking accuracy, because the nuclear reactor system is a complex nonlinear system with uncertain parameters and disturbances. A sort of non-parameter model is constructed with the open-loop impulse response of the system. Furthermore, a sort of thermal power tracking digital control law is presented using the multi-step model algorithmic control principle. The control method presented had good tracking performance and robustness. It can work despite the existence of unmeasurable disturbances. The simulation experiment testifies the correctness and effectiveness of the method. The high accuracy matching between the thermal power and the referenced load is achieved

TheBrain Technologies Corporation: Collapsing the Time to Knowledge.

Science.gov (United States)

Misek, Marla

2003-01-01

TheBrain was created to take advantage of the most powerful information processor in existence - the human mind. Explains products of TheBrain Technologies Corporation,, which has developed computer interfaces to help individual users and corporations organize information in ways that make sense to them in the proper context. Describes a…

Evaluation of power history during power burst experiments in TRACY by combination of gamma-ray and thermal neutron detectors

International Nuclear Information System (INIS)

Yanagisawa, Hiroshi; Ohno, Akio

2002-01-01

A combination method using γ-ray and thermal neutron detectors was newly applied to the accurate evaluation of power histories during reactivity-initiated power burst experiments in the Transient Experiment Critical Facility (TRACY). During an initial power burst, the power history was determined using a fast response γ-ray ionization chamber, which was used because of its ability to exactly trace the power history within a short duration of the initial burst. After the initial burst, a micro fission chamber containing highly enriched uranium was used for the determination of the power history because the γ-ray ionization chamber could not be applied due to the contribution of delayed γ-rays from fission products. By the present method, the power histories were evaluated for the experiments in the range of 1.50 to 2.93$ of the reactivity insertion. It was found that the peak power and integrated power as determined by the previous method using only the micro fission chamber were underestimated to be 40% and 30% in maximum, respectively, in comparison with the results from the present evaluation. The numerical simulation performed by using the Monte Carlo method indicated that the underestimation could be comprehended by considering the time delay of thermal neutron detection of the fission chamber, which arose from the flight-time of neutrons from the TRACY core to the fission chamber. (author)

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.

Ice Thermal Storage Systems for LWR Supplemental Cooling and Peak Power Shifting

Energy Technology Data Exchange (ETDEWEB)

Haihua Zhao; Hongbin Zhang; Phil Sharpe; Blaise Hamanaka; Wei Yan; WoonSeong Jeong

2010-06-01

Availability of enough cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. The issues become more severe due to the new round of nuclear power expansion and global warming. During hot summer days, cooling water leaving a power plant may become too hot to threaten aquatic life so that environmental regulations may force the plant to reduce power output or even temporarily to be shutdown. For new nuclear power plants to be built at areas without enough cooling water, dry cooling can be used to remove waste heat directly into the atmosphere. However, dry cooling will result in much lower thermal efficiency when the weather is hot. One potential solution for the above mentioned issues is to use ice thermal storage systems (ITS) that reduce cooling water requirements and boost the plant’s thermal efficiency in hot hours. ITS uses cheap off-peak electricity to make ice and uses those ice for supplemental cooling during peak demand time. ITS is suitable for supplemental cooling storage due to its very high energy storage density. ITS also provides a way to shift large amount of electricity from off peak time to peak time. Some gas turbine plants already use ITS to increase thermal efficiency during peak hours in summer. ITSs have also been widely used for building cooling to save energy cost. Among three cooling methods for LWR applications: once-through, wet cooling tower, and dry cooling tower, once-through cooling plants near a large water body like an ocean or a large lake and wet cooling plants can maintain the designed turbine backpressure (or condensation temperature) during 99% of the time; therefore, adding ITS to those plants will not generate large benefits. For once-through cooling plants near a limited water body like a river or a small lake, adding ITS can bring significant economic

Novel Functionally Graded Thermal Barrier Coatings in Coal-Fired Power Plant Turbines

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jing [Indiana Univ., Indianapolis, IN (United States)

2016-11-01

This project presents a detailed investigation of a novel functionally graded coating material, pyrochlore oxide, for thermal barrier coating (TBC) in gas turbines used in coal-fired power plants. Thermal barrier coatings are refractory materials deposited on gas turbine components, which provide thermal protection for metallic components at operating conditions. The ultimate goal of this research is to develop a manufacturing process to produce the novel low thermal conductivity and high thermal stability pyrochlore oxide based coatings with improved high-temperature durability. The current standard TBC, yttria stabilized zirconia (YSZ), has service temperatures limited to <1200°C, due to sintering and phase transition at higher temperatures. In contrast, pyrochlore oxide, e.g., lanthanum zirconate (La₂Zr₂O₇, LZ), has demonstrated lower thermal conductivity and better thermal stability, which are crucial to high temperature applications, such as gas turbines used in coal-fired power plants. Indiana University – Purdue University Indianapolis (IUPUI) has collaborated with Praxair Surface Technologies (PST), and Changwon National University in South Korea to perform the proposed research. The research findings are critical to the extension of current TBCs to a broader range of high-temperature materials and applications. Several tasks were originally proposed and accomplished, with additional new opportunities identified during the course of the project. In this report, a description of the project tasks, the main findings and conclusions are given. A list of publications and presentations resulted from this research is listed in the Appendix at the end of the report.

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.

Internal marketing for engaging employees on the corporate responsibility journey

OpenAIRE

Sanchez-Hernandez, Isabel; Grayson, David

2012-01-01

Purpose: The purpose of this paper is to explore whether internal marketing could be a powerful tool for engaging employees on the corporate responsibility journey. Design/methodology/approach: In the absence of empirical work linking internal marketing efforts in organizations and employee engagement in corporate responsibility issues, a conceptual approach based on literature review is carried out to determine the existing possibilities provided by internal marketing to enhance corporate re...

Thermal Impact Analysis of Circulating Current in High Power Modular Online Uninterruptible Power Supplies Application

DEFF Research Database (Denmark)

Zhang, Chi; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

2017-01-01

In modular uninterruptible power supplies (UPSs), several DC/AC modules are required to work in parallel. This structure allows the system to be more reliable and flexible. These DC/AC modules share the same DC bus and AC critical bus. Module differences, such as filter inductor, filter capacitor......, control parameters, and so on, will make it possible for the potential zero sequence current to flow among the modules. This undesired type of circulating current will bring extra losses to the power semiconductor devices in the system, which should be paid special attention in high power application...... scenarios. In this paper, plug’n’play modules and cycle control are discussed and validated through experimental results. Moreover, potential zero sequence circulating current impact on power semiconductor devices thermal performance is also analyzed in this paper....

Untrimmed Low-Power Thermal Sensor for SoC in 22 nm Digital Fabrication Technology

Directory of Open Access Journals (Sweden)

Ro'ee Eitan

2014-12-01

Full Text Available Thermal sensors (TS are essential for achieving optimized performance and reliability in the era of nanoscale microprocessor and system on chip (SoC. Compiling with the low-power and small die area of the mobile computing, the presented TS supports a wide range of sampling frequencies with an optimized power envelope. The TS supports up to 45 K samples/s, low average power consumption, as low as 20 μW, and small core Si area of 0.013 mm2. Advanced circuit techniques are used in order to overcome process variability, ensuring inaccuracy lower than ±2 °C without any calibration. All this makes the presented thermal sensor a cost-effective, low-power solution for 22 nm nanoscale digital process technology.