Thermoelectric powered wireless sensors for spent fuel monitoring

International Nuclear Information System (INIS)

Carstens, T.; Corradini, M.; Blanchard, J.; Ma, Z.

2011-01-01

This paper describes using thermoelectric generators to power wireless sensors to monitor spent nuclear fuel during dry-cask storage. OrigenArp was used to determine the decay heat of the spent fuel at different times during the service life of the dry-cask. The Engineering Equation Solver computer program modeled the temperatures inside the spent fuel storage facility during its service life. The temperature distribution in a thermoelectric generator and heat sink was calculated using the computer program Finite Element Heat Transfer. From these temperature distributions the power produced by the thermoelectric generator was determined as a function of the service life of the dry-cask. In addition, an estimation of the path loss experienced by the wireless signal can be made based on materials and thickness of the structure. Once the path loss is known, the transmission power and thermoelectric generator power requirements can be determined. This analysis estimates that a thermoelectric generator can produce enough power for a sensor to function and transmit data from inside the dry-cask throughout its service life. (authors)

Water: A critical resource in the thermoelectric power industry

International Nuclear Information System (INIS)

Feeley, Thomas J. III.; McNemar, Andrea; Skone, Timothy J.; Stiegel, Gary J. Jr.; Nemeth, Michael; Schimmoller, Brian; Murphy, James T.; Manfredo, Lynn

2008-01-01

Water availability represents a growing concern for meeting future power generation needs. In the United States, projected population growth rates, energy consumption patterns, and demand from competing water use sectors will increase pressure on power generators to reduce water use. Water availability and use also exhibit strong regional variations, complicating the nature of public policy and technological response. The US Department of Energy's (DOE) National Energy Technology Laboratory (NETL) is engaged in a research and development (R and D) program to reduce freshwater withdrawal (total quantity of water utilized) and consumption (portion of withdrawal not returned to the source) from existing and future thermoelectric power generating facilities. The Innovations for Existing Plants (IEP) Program is currently developing technologies in 5 categories of water management projects to reduce water use while minimizing the impacts of plant operations on water quality. This paper outlines the freshwater withdrawal and consumption rates for various thermoelectric power generating types and then estimates the potential benefits of IEP program technologies at both the national and regional levels in the year 2030. NETL is working to protect and conserve water resources while leveraging domestic fossil fuel resources, such as coal, to increase national energy security. (author)

Thermoelectric Power Factor Limit of a 1D Nanowire

Science.gov (United States)

Chen, I.-Ju; Burke, Adam; Svilans, Artis; Linke, Heiner; Thelander, Claes

2018-04-01

In the past decade, there has been significant interest in the potentially advantageous thermoelectric properties of one-dimensional (1D) nanowires, but it has been challenging to find high thermoelectric power factors based on 1D effects in practice. Here we point out that there is an upper limit to the thermoelectric power factor of nonballistic 1D nanowires, as a consequence of the recently established quantum bound of thermoelectric power output. We experimentally test this limit in quasiballistic InAs nanowires by extracting the maximum power factor of the first 1D subband through I -V characterization, finding that the measured maximum power factors conform to the theoretical limit. The established limit allows the prediction of the achievable power factor of a specific nanowire material system with 1D electronic transport based on the nanowire dimension and mean free path. The power factor of state-of-the-art semiconductor nanowires with small cross section and high crystal quality can be expected to be highly competitive (on the order of mW /m K2 ) at low temperatures. However, they have no clear advantage over bulk materials at, or above, room temperature.

An oxide-based thermoelectric generator: Transversal thermoelectric strip-device

Science.gov (United States)

Teichert, S.; Bochmann, A.; Reimann, T.; Schulz, T.; Dreßler, C.; Töpfer, J.

2015-07-01

A special design of an oxide-based transversal thermoelectric device utilizing thermoelectric oxides in combination with a ceramic multilayer technology is proposed. Metal strips within the ceramic matrix replace the tilted stack of alternating layers used in artificial anisotropic transversal thermoelectric devices. Numerical three-dimensional simulations of both device types reveal better thermoelectric performance data for the device with metal stripes. A monolithic transversal strip-device based on the material combination La1.97Sr0.03CuO4/Ag6Pd1 was prepared and electrically characterized. A maximum power output of 4.0 mW was determined at ΔT = 225 K for the monolithic device. The observed results are in remarkable agreement with three-dimensional numerical simulations utilizing the transport parameters of the two materials and the geometry data of the device.

Thermoelectric self-cooling for power electronics: Increasing the cooling power

International Nuclear Information System (INIS)

Martinez, Alvaro; Astrain, David; Aranguren, Patricia

2016-01-01

Thermoelectric self-cooling was firstly conceived to increase, without electricity consumption, the cooling power of passive cooling systems. This paper studies the combination of heat pipe exchangers and thermoelectric self-cooling, and demonstrates its applicability to the cooling of power electronics. Experimental tests indicate that source-to-ambient thermal resistance reduces by around 30% when thermoelectric self-cooling system is installed, compared to that of the heat pipe exchanger under natural convection. Neither additional electric power nor cooling fluids are required. This thermal resistance reaches 0.346 K/W for a heat flux of 24.1 kW/m"2, being one order of magnitude lower than that obtained in previous designs. In addition, the system adapts to the cooling demand, reducing this thermal resistance for increasing heat. Simulation tests have indicated that simple system modifications allow relevant improvements in the cooling power. Replacement of a thermoelectric module with a thermal bridge leads to 33.54 kW/m"2 of top cooling power. Likewise, thermoelectric modules with shorter legs and higher number of pairs lead to a top cooling power of 44.17 kW/m"2. These results demonstrate the applicability of thermoelectric self-cooling to power electronics. - Highlights: • Cooling power of passive systems increased. • No electric power consumption. • Applicable for the cooling of power electronics. • Up to 44.17 kW/m"2 of cooling power, one order of magnitude higher. • Source-to-ambient thermal resistance reduces by 30%.

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.

A flameless catalytic combustion-based thermoelectric generator for powering electronic instruments on gas pipelines

International Nuclear Information System (INIS)

Xiao, Heng; Qiu, Kuanrong; Gou, Xiaolong; Ou, Qiang

2013-01-01

Highlights: ► MPPT is used to improve the feature that TEG output is sensitive to load variation. ► The improved feature makes TEG suitable to power electronic device on gas pipeline. ► Test shows heat transfer uniformity plays an important role in improving TEG output. ► It can get an optimized TEG by uniformly filling a thermal insulation material. - Abstract: This paper presents a flameless catalytic combustion-based thermoelectric power generator that uses commercial thermoelectric modules. The structure of the thermoelectric generator (TEG) is introduced and the power performance is measured based on a designed circuit system. The open circuit voltage of the TEG is about 7.3 V. The maximum power output can reach up to 6.5 W when the load resistance matches the TEG internal resistance. However, the system output is sensitive to load variation. To improve this characteristic, maximum power point tracking technique is used and results in an open circuit voltage of 13.8 V. The improved characteristic makes the TEG system a good charger to keep the lead acid battery fully charged so as to meet the needs of electronic instruments on gas pipelines. In addition, the combustion features have been investigated based on the temperature measurement. Test results show that the uniformity of combustion heat transfer process and the combustion chamber structure play important roles in improving system power output. It can get an optimized TEG system (maximum power output: 8.3 W) by uniformly filling a thermal insulation material (asbestos) to avoid a non-uniform combustion heat transfer process

Development of life cycle water-demand coefficients for coal-based power generation technologies

International Nuclear Information System (INIS)

Ali, Babkir; Kumar, Amit

2015-01-01

Highlights: • We develop water consumption and withdrawals coefficients for coal power generation. • We develop life cycle water footprints for 36 coal-based electricity generation pathways. • Different coal power generation technologies were assessed. • Sensitivity analysis of plant performance and coal transportation on water demand. - Abstract: This paper aims to develop benchmark coefficients for water consumption and water withdrawals over the full life cycle of coal-based power generation. This study considered not only all of the unit operations involved in the full electricity generation life cycle but also compared different coal-based power generating technologies. Overall this study develops the life cycle water footprint for 36 different coal-based electricity generation pathways. Power generation pathways involving new technologies of integrated gasification combined cycle (IGCC) or ultra supercritical technology with coal transportation by conventional means and using dry cooling systems have the least complete life cycle water-demand coefficients of about 1 L/kW h. Sensitivity analysis is conducted to study the impact of power plant performance and coal transportation on the water demand coefficients. The consumption coefficient over life cycle of ultra supercritical or IGCC power plants are 0.12 L/kW h higher when conventional transportation of coal is replaced by coal-log pipeline. Similarly, if the conventional transportation of coal is replaced by its transportation in the form of a slurry through a pipeline, the consumption coefficient of a subcritical power plant increases by 0.52 L/kW h

A novel self-powered wireless temperature sensor based on thermoelectric generators

International Nuclear Information System (INIS)

Shi, Yongming; Wang, Yao; Deng, Yuan; Gao, Hongli; Lin, Zhen; Zhu, Wei; Ye, Huihong

2014-01-01

Highlights: • A self-powered temperature sensor, based on thermoelectric generator, is presented. • This novel sensor can operate without any batteries or other power sources. • This sensor combines signal sensing and power supplying together. • The measurement error is 0.5 K during the sensor operating period. • This sensor can detect temperature fluctuation situations such as fire disaster. - Abstract: A novel self-powered wireless temperature sensor has been designed and presented for solving the power supply problem of temperature sensors. This sensor can autonomously measure temperature under positive temperature fluctuation situations. The self-powered characteristic, realized by using four thermoelectric generators, enables the sensor to operate without any batteries or other power sources. In order to obtain these features, attentions are not only focused on the method to combine signal sensing and power generating together, but also on the method to improve measurement accuracy. Experimental results confirm that this novel sensor has excellent measurement accuracy. The measured performance is consistent with the calculated characteristics. For typical application, this self-powered temperature sensor can detect fire before it develops to flashover state. And the maximum detection distance grows with the growth of burning rate. All the results indicate this innovative sensor is a promising self-powered device which can be used to measure temperature value in positive temperature fluctuation situations

Enhanced thermoelectric power in two-dimensional transition metal dichalcogenide monolayers

KAUST Repository

Pu, Jiang

2016-07-27

The carrier-density-dependent conductance and thermoelectric properties of large-area MoS2 and WSe2 monolayers are simultaneously investigated using the electrolyte gating method. The sign of the thermoelectric power changes across the transistor off-state in the ambipolar WSe2 transistor as the majority carrier density switches from electron to hole. The thermopower and thermoelectric power factor of monolayer samples are one order of magnitude larger than that of bulk materials, and their carrier-density dependences exhibit a quantitative agreement with the semiclassical Mott relation based on the two-dimensional energy band structure, concluding the thermoelectric properties are enhanced by the low-dimensional effect.

Evaluating the Thermal Pollution Caused by Wastewaters Discharged from a Chain of Coal-Fired Power Plants along a River

Directory of Open Access Journals (Sweden)

Marc A. Rosen

2015-05-01

Full Text Available Reliable and safe operation of a coal-fired power plant is strongly linked to freshwater resources, and environmental problems related to water sources and wastewater discharge are challenges for power station operation. In this study, an evaluation on the basis of a wastewater thermal pollution vector is reported for the environmental impact of residual water generated and discharged in the Jiu River during the operation of thermoelectric units of the Rovinari, Turceni and Craiova coal-fired power plants in Romania. Wastewater thermal pollutant vector Plane Projection is applied for assessing the water temperature evolution in the water flow lane created downstream of each power plant wastewater outlet channel. Simulation on the basis of an Electricity of France model, and testing validation of the results for thermoelectric units of 330 MW of these power plants are presented.

Relative radiation hazards of coal based and nuclear power plants

International Nuclear Information System (INIS)

Mishra, U.C.

1983-04-01

Coal, like most materials found in nature, contains trace quantities of naturally occurring radionuclides. However, low concentrations may become important if large quantities of coal are burnt in thermal power plants. Therefore a study was performed to determine the radioactivity in coal, in fly-ash and slag and assess the importance of radioactive emissions from thermal power plants. The results were compared to the radiological impact of nuclear power stations. Based on these data, theoretical estimates for the population living within 80km from power stations indicate that the collective dose commitments of coal-fired plants are one order of magnitude higher than those for BWR-type nuclear plants. Measurements taken in the vicinity of coal-fired plants were comparable to those for nuclear plants, i.e. within the range of variation of natural background radiation in India

Development of self-powered wireless high temperature electrochemical sensor for in situ corrosion monitoring of coal-fired power plant.

Science.gov (United States)

Aung, Naing Naing; Crowe, Edward; Liu, Xingbo

2015-03-01

Reliable wireless high temperature electrochemical sensor technology is needed to provide in situ corrosion information for optimal predictive maintenance to ensure a high level of operational effectiveness under the harsh conditions present in coal-fired power generation systems. This research highlights the effectiveness of our novel high temperature electrochemical sensor for in situ coal ash hot corrosion monitoring in combination with the application of wireless communication and an energy harvesting thermoelectric generator (TEG). This self-powered sensor demonstrates the successful wireless transmission of both corrosion potential and corrosion current signals to a simulated control room environment. Copyright © 2014 ISA. All rights reserved.

Nanostructured Bulk Thermoelectric Generator for Efficient Power Harvesting for Self-powered Sensor Networks

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yanliang [Idaho National Lab. (INL), Idaho Falls, ID (United States); Butt, Darryl [Idaho National Lab. (INL), Idaho Falls, ID (United States); Agarwal, Vivek [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-07-01

The objective of this Nuclear Energy Enabling Technology research project is to develop high-efficiency and reliable thermoelectric generators for self-powered wireless sensors nodes utilizing thermal energy from nuclear plant or fuel cycle. The power harvesting technology has crosscutting significance to address critical technology gaps in monitoring nuclear plants and fuel cycle. The outcomes of the project will lead to significant advancement in sensors and instrumentation technology, reducing cost, improving monitoring reliability and therefore enhancing safety. The self-powered wireless sensor networks could support the long-term safe and economical operation of all the reactor designs and fuel cycle concepts, as well as spent fuel storage and many other nuclear science and engineering applications. The research is based on recent breakthroughs in high-performance nanostructured bulk (nanobulk) thermoelectric materials that enable high-efficiency direct heat-to-electricity conversion over a wide temperature range. The nanobulk thermoelectric materials that the research team at Boise State University and University of Houston has developed yield up to a 50% increase in the thermoelectric figure of merit, ZT, compared with state-of-the-art bulk counterparts. This report focuses on the selection of optimal thermoelectric materials for this project. The team has performed extensive study on two thermoelectric materials systems, i.e. the half-Heusler materials, and the Bismuth-Telluride materials. The report contains our recent research results on the fabrication, characterization and thermoelectric property measurements of these two materials.

Uninterrupted thermoelectric energy harvesting using temperature-sensor-based maximum power point tracking system

International Nuclear Information System (INIS)

Park, Jae-Do; Lee, Hohyun; Bond, Matthew

2014-01-01

Highlights: • Feedforward MPPT scheme for uninterrupted TEG energy harvesting is suggested. • Temperature sensors are used to avoid current measurement or source disconnection. • MPP voltage reference is generated based on OCV vs. temperature differential model. • Optimal operating condition is maintained using hysteresis controller. • Any type of power converter can be used in the proposed scheme. - Abstract: In this paper, a thermoelectric generator (TEG) energy harvesting system with a temperature-sensor-based maximum power point tracking (MPPT) method is presented. Conventional MPPT algorithms for photovoltaic cells may not be suitable for thermoelectric power generation because a significant amount of time is required for TEG systems to reach a steady state. Moreover, complexity and additional power consumption in conventional circuits and periodic disconnection of power source are not desirable for low-power energy harvesting applications. The proposed system can track the varying maximum power point (MPP) with a simple and inexpensive temperature-sensor-based circuit without instantaneous power measurement or TEG disconnection. This system uses TEG’s open circuit voltage (OCV) characteristic with respect to temperature gradient to generate a proper reference voltage signal, i.e., half of the TEG’s OCV. The power converter controller maintains the TEG output voltage at the reference level so that the maximum power can be extracted for the given temperature condition. This feedforward MPPT scheme is inherently stable and can be implemented without any complex microcontroller circuit. The proposed system has been validated analytically and experimentally, and shows a maximum power tracking error of 1.15%

Thermoelectric power generator with intermediate loop

Science.gov (United States)

Bell, Lon E; Crane, Douglas Todd

2013-05-21

A thermoelectric power generator is disclosed for use to generate electrical power from heat, typically waste heat. An intermediate heat transfer loop forms a part of the system to permit added control and adjustability in the system. This allows the thermoelectric power generator to more effectively and efficiently generate power in the face of dynamically varying temperatures and heat flux conditions, such as where the heat source is the exhaust of an automobile, or any other heat source with dynamic temperature and heat flux conditions.

Portable Thermoelectric Power Generator Coupled with Phase Change Material

Directory of Open Access Journals (Sweden)

Lim Chong C.

2014-07-01

Full Text Available Solar is the intermittent source of renewable energy and all thermal solar systems having a setback on non-functioning during the night and cloudy environment. This paper presents alternative solution for power generation using thermoelectric which is the direct conversion of temperature gradient of hot side and cold side of thermoelectric material to electric voltage. Phase change material with latent heat effect would help to prolong the temperature gradient across thermoelectric material for power generation. Besides, the concept of portability will enable different power source like solar, wasted heat from air conditioner, refrigerator, stove etc, i.e. to create temperature different on thermoelectric material for power generation. Furthermore, thermoelectric will generate direct current which is used by all the gadgets like Smartphone, tablet, laptop etc. The portable concept of renewable energy will encourage the direct usage of renewable energy for portable gadgets. The working principle and design of portable thermoelectric power generator coupled with phase change material is presented in this paper.

Energy Optimization for a Weak Hybrid Power System of an Automobile Exhaust Thermoelectric Generator

Science.gov (United States)

Fang, Wei; Quan, Shuhai; Xie, Changjun; Tang, Xinfeng; Ran, Bin; Jiao, Yatian

2017-11-01

An integrated starter generator (ISG)-type hybrid electric vehicle (HEV) scheme is proposed based on the automobile exhaust thermoelectric generator (AETEG). An eddy current dynamometer is used to simulate the vehicle's dynamic cycle. A weak ISG hybrid bench test system is constructed to test the 48 V output from the power supply system, which is based on engine exhaust-based heat power generation. The thermoelectric power generation-based system must ultimately be tested when integrated into the ISG weak hybrid mixed power system. The test process is divided into two steps: comprehensive simulation and vehicle-based testing. The system's dynamic process is simulated for both conventional and thermoelectric powers, and the dynamic running process comprises four stages: starting, acceleration, cruising and braking. The quantity of fuel available and battery pack energy, which are used as target vehicle energy functions for comparison with conventional systems, are simplified into a single energy target function, and the battery pack's output current is used as the control variable in the thermoelectric hybrid energy optimization model. The system's optimal battery pack output current function is resolved when its dynamic operating process is considered as part of the hybrid thermoelectric power generation system. In the experiments, the system bench is tested using conventional power and hybrid thermoelectric power for the four dynamic operation stages. The optimal battery pack curve is calculated by functional analysis. In the vehicle, a power control unit is used to control the battery pack's output current and minimize energy consumption. Data analysis shows that the fuel economy of the hybrid power system under European Driving Cycle conditions is improved by 14.7% when compared with conventional systems.

Applications of nuclear-powered thermoelectric generators in space

International Nuclear Information System (INIS)

Rowe, D.M.

1991-01-01

The source of electrical power which enables information to be transmitted from the space crafts Voyager 1 and 2 back to Earth after a time period of more than a decade and at a distance of more than a billion miles is known as an RTG (radioisotope thermoelectric generator). It utilises the Seebeck effect in producing electricity from heat. In essence it consists of a large number of semiconductor thermocouples connected electrically in series and thermally in parallel. A temperature difference is maintained across the thermocouples by providing a heat source, which in the case of an RTG is a radioactive isotope, and the heat sink is space. The combination of an energy-conversion system, free of moving parts and a long-life, high energy-density heat source, provides a supply of electrical power typically in the range of tens to hundred of watts and which operates reliably over extended periods of time. An electric power source, based upon thermoelectric conversion by which utilises a nuclear reactor as a heat source, has also been deployed in space and a 100-kW system is being developed to provide electrical power to a variety of commercial and military projects including SDI. Developments in thermoelectrics that have taken place in the western world during the past 30 years are primarily due to United States interest and involvement in the exploration of space. This paper reviews US applications of nuclear-powered thermoelectric generators in space. (author)

Thermoelectric power and electrical conductivity of strontium-doped lanthanum manganite

DEFF Research Database (Denmark)

Ahlgren, E.O.; Poulsen, F.W.

1996-01-01

Thermoelectric power and electrical conductivity of pure and 5, 10 and 20% strontium-doped lanthanum manganite are determined as function of temperature in air and of P-O2 at 1000 degrees C. At high temperatures the thermoelectric power is negative. Both thermoelectric power and conductivity...

Research Progress on AgSbTe2-based Thermoelectric Materials

Institute of Scientific and Technical Information of China (English)

CAO Qigao; MA Guang; JIA Zhihua; ZHENG Jing; LI Jin

2012-01-01

Thermoelectric power generation represents a class of energy conversion technology,which has been used in power supply of aeronautic and astronautic exploring missions,now showing notable advantages to harvest the widely distributed waste heat and convert the abundant solar energy into electricity at lower cost than Si-based photovoltaic technology.Thermoelectric dimensionless figure of merit ZT plays a key role in the conversion efficiency from thermal to electrical energy.Low thermal conductivity and large Seebeck coefficient make the AgSbTe2 compound a very promising candidate for high efficiency p-type thermoelectric applications.The AgSbTe2-based thermoelectric system has been repeatedly studied as prospective thermoelectric materials.In this review,we firstly clarify some fundamental tradeoffs dictating the ZT value through the relationship ZT =S2σT/κ.We also pay special attentions to the recent advances in AgSbTe2-based thermoelectric materials.Finally,we provide an outlook of new directions in this filed.

Increasing efficiency and optimizing thermoelectric power plant equipment. Povyshenie effektivnosti i optimizatsiia teploenergeticheskikh ustanovok

Energy Technology Data Exchange (ETDEWEB)

Andriushchenko, A.I.

1981-01-01

The problems of increasing the efficiency and optimizing the operational conditions of a thermoelectric power plant and providing efficient operational conditions of the primary and auxillary equipment at a thermoelectric power plant are examined. Methodologies and designs for optimizing the primary parameters of the power-generating equipment based on economic factors are given. A number of recommendations for designing equipment based on the research results are given.

Methods for estimating water consumption for thermoelectric power plants in the United States

Science.gov (United States)

Diehl, Timothy H.; Harris, Melissa; Murphy, Jennifer C.; Hutson, Susan S.; Ladd, David E.

2013-01-01

Water consumption at thermoelectric power plants represents a small but substantial share of total water consumption in the U.S. However, currently available thermoelectric water consumption data are inconsistent and incomplete, and coefficients used to estimate consumption are contradictory. The U.S. Geological Survey (USGS) has resumed the estimation of thermoelectric water consumption, last done in 1995, based on the use of linked heat and water budgets to complement reported water consumption. This report presents the methods used to estimate freshwater consumption at a study set of 1,284 power plants based on 2010 plant characteristics and operations data.

Power generation enhancement in a salinity-gradient solar pond power plant using thermoelectric generator

International Nuclear Information System (INIS)

Ziapour, Behrooz M.; Saadat, Mohammad; Palideh, Vahid; Afzal, Sadegh

2017-01-01

Highlights: • Thermoelectric generator was used and simulated within a salinity-gradient solar pond power plant. • Results showed that the thermoelectric generator can be able to enhance the power plant efficiency. • Results showed that the presented models can be able to produce generation even in the cold months. • The optimum size of area of solar pond based on its effect on efficiency is 50,000 m 2 . - Abstract: Salinity-gradient solar pond (SGSP) has been a reliable supply of heat source for power generation when it has been integrated with low temperature thermodynamics cycles like organic Rankine cycle (ORC). Also, thermoelectric generator (TEG) plays a critical role in the production of electricity from renewable energy sources. This paper investigates the potential of thermoelectric generator as a power generation system using heat from SGSP. In this work, thermoelectric generator was used instead of condenser of ORC with the purpose of improving the performance of system. Two new models of SGSP have been presented as: (1) SGSP using TEG in condenser of ORC without heat exchanger and (2) SGSP using TEG in condenser of ORC with heat exchanger. These proposed systems was evaluated through computer simulations. The ambient conditions were collected from beach of Urmia lake in IRAN. Simulation results indicated that, for identical conditions, the model 1 has higher performance than other model 2. For models 1 and 2 in T LCZ = 90 °C, the overall thermal efficiency of the solar pond power plant, were obtained 0.21% and 0.2% more than ORC without TEG, respectively.

Carbon-Nanotube-Based Thermoelectric Materials and Devices

Energy Technology Data Exchange (ETDEWEB)

Blackburn, Jeffrey L. [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, Golden CO 80401-3305 USA; Ferguson, Andrew J. [Chemistry and Nanoscience Center, National Renewable Energy Laboratory, Golden CO 80401-3305 USA; Cho, Chungyeon [Department of Mechanical Engineering, Texas A& M University, College Station TX 77843-3003 USA; Grunlan, Jaime C. [Department of Mechanical Engineering, Texas A& M University, College Station TX 77843-3003 USA

2018-01-22

Conversion of waste heat to voltage has the potential to significantly reduce the carbon footprint of a number of critical energy sectors, such as the transportation and electricity-generation sectors, and manufacturing processes. Thermal energy is also an abundant low-flux source that can be harnessed to power portable/wearable electronic devices and critical components in remote off-grid locations. As such, a number of different inorganic and organic materials are being explored for their potential in thermoelectric-energy-harvesting devices. Carbon-based thermoelectric materials are particularly attractive due to their use of nontoxic, abundant source-materials, their amenability to high-throughput solution-phase fabrication routes, and the high specific energy (i.e., W g-1) enabled by their low mass. Single-walled carbon nanotubes (SWCNTs) represent a unique 1D carbon allotrope with structural, electrical, and thermal properties that enable efficient thermoelectric-energy conversion. Here, the progress made toward understanding the fundamental thermoelectric properties of SWCNTs, nanotube-based composites, and thermoelectric devices prepared from these materials is reviewed in detail. This progress illuminates the tremendous potential that carbon-nanotube-based materials and composites have for producing high-performance next-generation devices for thermoelectric-energy harvesting.

Synechococcus nidulans from a thermoelectric coal power plant as a potential CO2 mitigation in culture medium containing flue gas wastes.

Science.gov (United States)

Duarte, Jessica Hartwig; Costa, Jorge Alberto Vieira

2017-10-01

This study evaluated the intermittent addition of coal flue gas wastes (CO 2 , SO 2 , NO and ash) into a Synechococcus nidulans LEB 115 cultivation in terms of growth parameters, CO 2 biofixation and biomass characterization. The microalga from a coal thermoelectric plant showed tolerance up to 200ppm SO 2 and NO, with a maximum specific growth rate of 0.18±0.03d - 1 . The addition of thermal coal ash to the cultivation increased the Synechococcus nidulans LEB 115 maximum cell growth by approximately 1.3 times. The best CO 2 biofixation efficiency was obtained with 10% CO 2 , 60ppm SO 2 , 100ppm NO and 40ppm ash (55.0±3.1%). The biomass compositions in the assays were similar, with approximately 9.8% carbohydrates, 13.5% lipids and 62.7% proteins. Copyright © 2017 Elsevier Ltd. All rights reserved.

Scenario-Based Analysis on Water Resources Implication of Coal Power in Western China

Directory of Open Access Journals (Sweden)

Jiahai Yuan

2014-10-01

Full Text Available Currently, 58% of coal-fired power generation capacity is located in eastern China, where the demand for electricity is strong. Serious air pollution in China, in eastern regions in particular, has compelled the Chinese government to impose a ban on the new construction of pulverized coal power plants in eastern regions. Meanwhile, rapid economic growth is thirsty for electric power supply. As a response, China planned to build large-scale coal power bases in six western provinces, including Inner Mongolia, Shanxi, Shaanxi, Xinjiang, Ningxia and Gansu. In this paper, the water resource implication of the coal power base planning is addressed. We find that, in a business-as-usual (BAU scenario, water consumption for coal power generation in these six provinces will increase from 1130 million m3 in 2012 to 2085 million m3 in 2020, experiencing nearly a double growth. Such a surge will exert great pressure on water supply and lead to serious water crisis in these already water-starved regions. A strong implication is that the Chinese Government must add water resource constraint as a critical point in its overall sustainable development plan, in addition to energy supply and environment protection. An integrated energy-water resource plan with regionalized environmental carrying capacity as constraints should be developed to settle this puzzle. Several measures are proposed to cope with it, including downsizing coal power in western regions, raising the technical threshold of new coal power plants and implementing retrofitting to the inefficient cooling system, and reengineering the generation process to waterless or recycled means.

Use of thermoelectric generators for improve power dependability over grid power

Energy Technology Data Exchange (ETDEWEB)

Archer, Jack [Global Thermoelectric, Calgary (Canada)

2005-07-01

A natural gas transportation company was experiencing extensive pipeline corrosion on some sections of their pipeline protected by impressed current using grid power and rectifiers. After determining that grid power was being interrupted on the affected sections, the gas transporter began looking for a more dependable power supply and chose thermoelectric generators. Since installing thermoelectric generators in 2002, the pipeline potentials have stabilized and transporter was able to experience 100% operational time on affected sections. (author)

A 3D TCAD simulation of a thermoelectric module configured for thermoelectric power generation, cooling and heating

Science.gov (United States)

Gould, C. A.; Shammas, N. Y. A.; Grainger, S.; Taylor, I.; Simpson, K.

2012-06-01

This paper documents the 3D modeling and simulation of a three couple thermoelectric module using the Synopsys Technology Computer Aided Design (TCAD) semiconductor simulation software. Simulation results are presented for thermoelectric power generation, cooling and heating, and successfully demonstrate the basic thermoelectric principles. The 3D TCAD simulation model of a three couple thermoelectric module can be used in the future to evaluate different thermoelectric materials, device structures, and improve the efficiency and performance of thermoelectric modules.

Carbon-Nanotube-Based Thermoelectric Materials and Devices.

Science.gov (United States)

Blackburn, Jeffrey L; Ferguson, Andrew J; Cho, Chungyeon; Grunlan, Jaime C

2018-03-01

Conversion of waste heat to voltage has the potential to significantly reduce the carbon footprint of a number of critical energy sectors, such as the transportation and electricity-generation sectors, and manufacturing processes. Thermal energy is also an abundant low-flux source that can be harnessed to power portable/wearable electronic devices and critical components in remote off-grid locations. As such, a number of different inorganic and organic materials are being explored for their potential in thermoelectric-energy-harvesting devices. Carbon-based thermoelectric materials are particularly attractive due to their use of nontoxic, abundant source-materials, their amenability to high-throughput solution-phase fabrication routes, and the high specific energy (i.e., W g -1 ) enabled by their low mass. Single-walled carbon nanotubes (SWCNTs) represent a unique 1D carbon allotrope with structural, electrical, and thermal properties that enable efficient thermoelectric-energy conversion. Here, the progress made toward understanding the fundamental thermoelectric properties of SWCNTs, nanotube-based composites, and thermoelectric devices prepared from these materials is reviewed in detail. This progress illuminates the tremendous potential that carbon-nanotube-based materials and composites have for producing high-performance next-generation devices for thermoelectric-energy harvesting. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Magnetic tunnel junction thermocouple for thermoelectric power harvesting

Science.gov (United States)

Böhnert, T.; Paz, E.; Ferreira, R.; Freitas, P. P.

2018-05-01

The thermoelectric power generated in magnetic tunnel junctions (MTJs) is determined as a function of the tunnel barrier thickness for a matched electric circuit. This study suggests that lower resistance area product and higher tunnel magnetoresistance will maximize the thermoelectric power output of the MTJ structures. Further, the thermoelectric behavior of a series of two MTJs, a MTJ thermocouple, is investigated as a function of its magnetic configurations. In an alternating magnetic configurations the thermovoltages cancel each other, while the magnetic contribution remains. A large array of MTJ thermocouples could amplify the magnetic thermovoltage signal significantly.

Life cycle energy use and GHG emission assessment of coal-based SNG and power cogeneration technology in China

International Nuclear Information System (INIS)

Li, Sheng; Gao, Lin; Jin, Hongguang

2016-01-01

Highlights: • Life cycle energy use and GHG emissions are assessed for SNG and power cogeneration. • A model based on a Chinese domestic database is developed for evaluation. • Cogeneration shows lower GHG emissions than coal-power pathway. • Cogeneration has lower life cycle energy use than supercritical coal-power pathway. • Cogeneration is a good option to implement China’s clean coal technologies. - Abstract: Life cycle energy use and GHG emissions are assessed for coal-based synthetic natural gas (SNG) and power cogeneration/polygenereation (PG) technology and its competitive alternatives. Four main SNG applications are considered, including electricity generation, steam production, SNG vehicle and battery electric vehicle (BEV). Analyses show that if SNG is produced from a single product plant, the lower limits of its life cycle energy use and GHG emissions can be comparable to the average levels of coal-power and coal-BEV pathways, but are still higher than supercritical and ultra supercritical (USC) coal-power and coal-BEV pathways. If SNG is coproduced from a PG plant, when it is used for power generation, steam production, and driving BEV car, the life cycle energy uses for PG based pathways are typically lower than supercritical coal-power pathways, but are still 1.6–2.4% higher than USC coal-power pathways, and the average life cycle GHG emissions are lower than those of all coal-power pathways including USC units. If SNG is used to drive vehicle car, the life cycle energy use and GHG emissions of PG-SNGV-power pathway are both much higher than all combined coal-BEV and coal-power pathways, due to much higher energy consumption in a SNG driven car than in a BEV car. The coal-based SNG and power cogeneration technology shows comparable or better energy and environmental performances when compared to other coal-based alternatives, and is a good option to implement China’s clean coal technologies.

Design of segmented thermoelectric generator based on cost-effective and light-weight thermoelectric alloys

International Nuclear Information System (INIS)

Kim, Hee Seok; Kikuchi, Keiko; Itoh, Takashi; Iida, Tsutomu; Taya, Minoru

2014-01-01

Highlights: • Segmented thermoelectric (TE) module operating at 500 °C for combustion engine system. • Si based light-weight TE generator increases the specific power density [W/kg]. • Study of contact resistance at the bonding interfaces maximizing output power. • Accurate agreement of the theoretical predictions with experimental results. - Abstract: A segmented thermoelectric (TE) generator was designed with higher temperature segments composed of n-type Mg 2 Si and p-type higher manganese silicide (HMS) and lower temperature segments composed of n- and p-type Bi–Te based compounds. Since magnesium and silicon based TE alloys have low densities, they produce a TE module with a high specific power density that is suitable for airborne applications. A two-pair segmented π-shaped TE generator was assembled with low contact resistance materials across bonding interfaces. The peak specific power density of this generator was measured at 42.9 W/kg under a 498 °C temperature difference, which has a good agreement with analytical predictions

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)

Stochastic Drought Risk Analysis and Projection Methods For Thermoelectric Power Systems

Science.gov (United States)

Bekera, Behailu Belamo

Combined effects of socio-economic, environmental, technological and political factors impact fresh cooling water availability, which is among the most important elements of thermoelectric power plant site selection and evaluation criteria. With increased variability and changes in hydrologic statistical stationarity, one concern is the increased occurrence of extreme drought events that may be attributable to climatic changes. As hydrological systems are altered, operators of thermoelectric power plants need to ensure a reliable supply of water for cooling and generation requirements. The effects of climate change are expected to influence hydrological systems at multiple scales, possibly leading to reduced efficiency of thermoelectric power plants. This study models and analyzes drought characteristics from a thermoelectric systems operational and regulation perspective. A systematic approach to characterize a stream environment in relation to extreme drought occurrence, duration and deficit-volume is proposed and demonstrated. More specifically, the objective of this research is to propose a stochastic water supply risk analysis and projection methods from thermoelectric power systems operation and management perspectives. The study defines thermoelectric drought as a shortage of cooling water due to stressed supply or beyond operable water temperature limits for an extended period of time requiring power plants to reduce production or completely shut down. It presents a thermoelectric drought risk characterization framework that considers heat content and water quantity facets of adequate water availability for uninterrupted operation of such plants and safety of its surroundings. In addition, it outlines mechanisms to identify rate of occurrences of the said droughts and stochastically quantify subsequent potential losses to the sector. This mechanism is enabled through a model based on compound Nonhomogeneous Poisson Process. This study also demonstrates how

Freshwater Availability and Constraints on Thermoelectric Power Generation in the Southeast U.S

International Nuclear Information System (INIS)

Feldman, David; Slough, Amanda; Garrett, Gary

2008-01-01

There is a myriad of uses to which our country's freshwater supply is currently committed. Together with increasing quantities of consumption, there are growing constraints on water availability. In our future there will be two elements of consumption at the forefront of concern: availability and efficiency. Availability of freshwater is the most important of these and is the subject of this report. To use water efficiently, we must first have it. Efficiency is key to ensuring availability for future needs. As population grows and economic and technology demands increase - especially for thermoelectric power - needs for freshwater will also increase. Thus, using our limited supplies of freshwater must be done as efficiently as possible. Thermoelectric generating industry is the largest user of our nation's water resources, including fresh, surface, ground, and saline water. Saline water use accounts for approximately 30% of thermoelectric use, while the remaining 70% is from freshwater sources. The U.S. Geological Survey (USGS) estimates that thermoelectric generation accounts for roughly 136,000 million gallons per day (MGD), or 39% of freshwater withdrawals. This ranks slightly behind agricultural irrigation as the top source of freshwater withdrawals in the U.S. in 2000. For Americans to preserve their standard of living and maintain a thriving economy it is essential that greater attention be paid to freshwater availability in efforts to meet energy demands - particularly for electric power. According to projections by the Energy Information Administration's (EIA) Annual Energy Outlook 2006 (AEO 2006) anticipated growth of thermoelectric generating capacity will be 22% between 2005 and 2030. In the 2007 Report, EIA estimates that capacity to grow from approximately 709 GW in 2005 to 862 GW in 20303. These large increases in generating capacity will result in increased water demands by thermoelectric power plants and greater competition over water between the

Techno-Economic Feasibility of Highly Efficient Cost-Effective Thermoelectric-SOFC Hybrid Power Generation Systems

Energy Technology Data Exchange (ETDEWEB)

Jifeng Zhang; Jean Yamanis

2007-09-30

Solid oxide fuel cell (SOFC) systems have the potential to generate exhaust gas streams of high temperature, ranging from 400 to 800 C. These high temperature gas streams can be used for additional power generation with bottoming cycle technologies to achieve higher system power efficiency. One of the potential candidate bottoming cycles is power generation by means of thermoelectric (TE) devices, which have the inherent advantages of low noise, low maintenance and long life. This study was to analyze the feasibility of combining coal gas based SOFC and TE through system performance and cost techno-economic modeling in the context of multi-MW power plants, with 200 kW SOFC-TE module as building blocks. System and component concepts were generated for combining SOFC and TE covering electro-thermo-chemical system integration, power conditioning system (PCS) and component designs. SOFC cost and performance models previously developed at United Technologies Research Center were modified and used in overall system analysis. The TE model was validated and provided by BSST. The optimum system in terms of energy conversion efficiency was found to be a pressurized SOFC-TE, with system efficiency of 65.3% and cost of $390/kW of manufacturing cost. The pressurization ratio was approximately 4 and the assumed ZT of the TE was 2.5. System and component specifications were generated based on the modeling study. The major technology and cost barriers for maturing the system include pressurized SOFC stack using coal gas, the high temperature recycle blowers, and system control design. Finally, a 4-step development roadmap is proposed for future technology development, the first step being a 1 kW proof-of-concept demonstration unit.

Special Application Thermoelectric Micro Isotope Power Sources

International Nuclear Information System (INIS)

Heshmatpour, Ben; Lieberman, Al; Khayat, Mo; Leanna, Andrew; Dobry, Ted

2008-01-01

Promising design concepts for milliwatt (mW) size micro isotope power sources (MIPS) are being sought for use in various space and terrestrial applications, including a multitude of future NASA scientific missions and a range of military applications. To date, the radioisotope power sources (RPS) used on various space and terrestrial programs have provided power levels ranging from one-half to several hundred watts. In recent years, the increased use of smaller spacecraft and planned new scientific space missions by NASA, special terrestrial and military applications suggest the need for lower power, including mW level, radioisotope power sources. These power sources have the potential to enable such applications as long-lived meteorological or seismological stations distributed across planetary surfaces, surface probes, deep space micro-spacecraft and sub-satellites, terrestrial sensors, transmitters, and micro-electromechanical systems. The power requirements are in the range of 1 mW to several hundred mW. The primary technical requirements for space applications are long life, high reliability, high specific power, and high power density, and those for some special military uses are very high power density, specific power, reliability, low radiological induced degradation, and very low radiation leakage. Thermoelectric conversion is of particular interest because of its technological maturity and proven reliability. This paper summarizes the thermoelectric, thermal, and radioisotope heat source designs and presents the corresponding performance for a number of mW size thermoelectric micro isotope power sources

Thermoelectric coolers as power generators

International Nuclear Information System (INIS)

Burke, E.J.; Buist, R.J.

1984-01-01

There are many applications where thermoelectric (TE) coolers can be used effectively as power generators. The literature available on this subject is scarce and very limited in scope. This paper describes the configuration, capability, limitations and performance of TE coolers to be used as power generators. Also presented are performance curves enabling the user to design the optimum TE module for any given power generation application

Quantum Effects in the Thermoelectric Power Factor of Low-Dimensional Semiconductors.

Science.gov (United States)

Hung, Nguyen T; Hasdeo, Eddwi H; Nugraha, Ahmad R T; Dresselhaus, Mildred S; Saito, Riichiro

2016-07-15

We theoretically investigate the interplay between the confinement length L and the thermal de Broglie wavelength Λ to optimize the thermoelectric power factor of semiconducting materials. An analytical formula for the power factor is derived based on the one-band model assuming nondegenerate semiconductors to describe quantum effects on the power factor of the low-dimensional semiconductors. The power factor is enhanced for one- and two-dimensional semiconductors when L is smaller than Λ of the semiconductors. In this case, the low-dimensional semiconductors having L smaller than their Λ will give a better thermoelectric performance compared to their bulk counterpart. On the other hand, when L is larger than Λ, bulk semiconductors may give a higher power factor compared to the lower dimensional ones.

High-Efficiency, Nanowire Based Thermoelectric Devices for Radioisotope Power Conversion, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — This SBIR Phase I proposal responds to topic S3.03 of the 2010 NASA SBIR solicitation, for Power Generation and Conversion. Thermoelectric devices offer a simple and...

Behavior of a thermoelectric power generation device based on solar irradiation and the earth’s surface-air temperature difference

International Nuclear Information System (INIS)

Zhang, Zhe; Li, Wenbin; Kan, Jiangming

2015-01-01

Highlights: • A technical solution to the power supply of wireless sensor networks is presented. • The low voltage produced by TEG is boosted from less than 1 V to more than 4 V. • An output current and voltage of TEG device is acquired as 21.47 mA and 221 mV. • The device successfully provides output power 4.7 mW in no electricity conditions. • The thermo-economic value of TEG device is demonstrated. - Abstract: Motivated by the limited power supply of wireless sensors used to monitor the natural environment, for example, in forests, this study presents a technical solution by recycling solar irradiation heat using thermoelectric generators. Based on solar irradiation and the earth’s surface-air temperature difference, a new type of thermoelectric power generation device has been devised, the distinguishing features of which include the application of an all-glass heat-tube-type vacuum solar heat collection pipe to absorb and transfer solar energy without a water medium and the use of a thin heat dissipation tube to cool the earth surface air temperature. The effects of key parameters such as solar illumination, air temperature, load resistance, the proportional coefficient, output power and power generation efficiency for thermoelectric energy conversion are analyzed. The results of realistic outdoor experiments show that under a state of regular illumination at 3.75 × 10 4 lx, using one TEG module, the thermoelectric device is able to boost the voltage obtained from the natural solar irradiation from 221 mV to 4.41 V, with an output power of 4.7 mW. This means that the electrical energy generated can provide the power supply for low power consumption components, such as low power wireless sensors, ZigBee modules and other low power loads

Power Generation from Coal 2011

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

This report focuses mainly on developments to improve the performance of coal-based power generation technologies, which should be a priority -- particularly if carbon capture and storage takes longer to become established than currently projected. A close look is taken of the major ongoing developments in process technology, plant equipment, instrumentation and control. Coal is an important source of energy for the world, particularly for power generation. To meet the growth in demand for energy over the past decade, the contribution from coal has exceeded that of any other energy source. Additionally, coal has contributed almost half of total growth in electricity over the past decade. As a result, CO2 emissions from coal-fired power generation have increased markedly and continue to rise. More than 70% of CO2 emissions that arise from power generation are attributed to coal. To play its role in a sustainable energy future, its environmental footprint must be reduced; using coal more efficiently is an important first step. Beyond efficiency improvement, carbon capture and storage (CCS) must be deployed to make deep cuts in CO2 emissions. The need for energy and the economics of producing and supplying it to the end-user are central considerations in power plant construction and operation. Economic and regulatory conditions must be made consistent with the ambition to achieve higher efficiencies and lower emissions. In essence, clean coal technologies must be more widely deployed.

Study of thermoelectric systems applied to electric power generation

International Nuclear Information System (INIS)

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

2009-01-01

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

Critical review of thermoelectrics in modern power generation applications

Directory of Open Access Journals (Sweden)

Saqr Khalid M.

2009-01-01

Full Text Available The thermoelectric complementary effects have been discovered in the nineteenth century. However, their role in engineering applications has been very limited until the first half of the twentieth century, the beginning of space exploration era. Radioisotope thermoelectric generators have been the actual motive for the research community to develop efficient, reliable and advanced thermoelectrics. The efficiency of thermoelectric materials has been doubled several times during the past three decades. Nevertheless, there are numerous challenges to be resolved in order to develop thermoelectric systems for our modern applications. This paper discusses the recent advances in thermoelectric power systems and sheds the light on the main problematic concerns which confront contemporary research efforts in that field.

Thermoelectric Powered Wireless Sensors for Dry-Cask Storage

Science.gov (United States)

Carstens, Thomas Alan

This study focuses on the development of self-powered wireless sensors. These sensors can be used to measure key parameters in extreme environments; e.g., temperature monitoring for spent nuclear fuel during dry-cask storage. This study has developed a design methodology for these self-powered monitoring systems. The main elements that constitute this work consist of selecting and testing a power source for the wireless sensor, determination of the attenuation of the wireless signal, and testing the wireless sensor circuitry in an extreme environment. OrigenArp determined the decay heat and gamma/neutron source strength of the spent fuel throughout the service life of the dry-cask. A first principles analysis modeled the temperatures inside the dry-cask. A finite-element heat transfer code calculated the temperature distribution of the thermoelectric and heat sink. The temperature distributions determine the power produced by the thermoelectric. It was experimentally verified that a thermoelectric generator (HZ-14) with a DC/DC converter (Linear Technology LTC3108EDE) can power a transceiver (EmbedRF) at condition which represent prototypical conditions throughout and beyond the service life of the dry-cask. The wireless sensor is required to broadcast with enough power to overcome the attenuation from the dry-cask. It will be important to minimize the attenuation of the signal in order to broadcast with a small transmission power. To investigate the signal transmission through the dry-cask, CST Microwave Studio was used to determine the scattering parameter S2,1 for a horizontal dry-cask. Important parameters that can influence the transmission of the signal are antenna orientation, antenna placement, and transmission frequency. The thermoelectric generator, DC/DC converter, and transceiver were exposed to 60Co gamma radiation (exposure rate170.3 Rad/min) at the University of Wisconsin Medical Radiation Research Center. The effects of gamma radiation on the

Research report for fiscal 1998. Basic research for promoting joint implementation (rehabilitation of 300MW coal-fired thermoelectric power plants in China); 1998 nendo chosa hokokusho. Chugoku ni okeru 300MW sekitan karyoku hatsudensho rihabiri

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

Studies are made on the feasibility of the above project which aims at energy efficiency improvement and CO2 reduction at thermoelectric power plants. Opinions and comments are collected by hearing, and on-site surveys are conducted at Shandong Province Zouxian Power Plant, Anhui Province Luohe Power Plant, and Henan Province Yaomeng Power Plant. The conclusion reached is outlined below. In view of the current and future demand for electricity in China and of the network to be constructed, it is believed that the rehabilitation is a pressing task for improvement on efficiency and reliability at 300MW coal-fired power plants. As for air pollution, NOx and dust in addition to greenhouse gas will be reduced under the project. There will be 3-4% improvement in boiler efficiency and approximately 4% improvement in turbine efficiency, and, in this connection, there will be CO2 emission reduction of 140,400-154,900 tons/year per unit in case of 300MW coal-fired power plants. As for cost efficiency, it is inferred that investment will achieve an adequate result, with the number of years required for investment retrieval taken into consideration. (NEDO)

A study on heat transfer enhancement using flow channel inserts for thermoelectric power generation

International Nuclear Information System (INIS)

Lesage, Frédéric J.; Sempels, Éric V.; Lalande-Bertrand, Nathaniel

2013-01-01

Highlights: • Thermal enhancement in a thermoelectric liquid generator is tested. • Thermal enhancement is brought upon by flow impeding inserts. • CFD simulations attribute thermal enhancement to velocity field alterations. • Thermoelectric power enhancement is measured and discussed. • Power enhancement relative to adverse pressure drop is investigated. - Abstract: Thermoelectric power production has many potential applications that range from microelectronics heat management to large scale industrial waste-heat recovery. A low thermoelectric conversion efficiency of the current state of the art prevents wide spread use of thermoelectric modules. The difficulties lie in material conversion efficiency, module design, and thermal system management. The present study investigates thermoelectric power improvement due to heat transfer enhancement at the channel walls of a liquid-to-liquid thermoelectric generator brought upon by flow turbulating inserts. Care is taken to measure the adverse pressure drop due to the presence of flow impeding obstacles in order to measure the net thermoelectric power enhancement relative to an absence of inserts. The results illustrate the power enhancement performance of three different geometric forms fitted into the channels of a thermoelectric generator. Spiral inserts are shown to offer a minimal improvement in thermoelectric power production whereas inserts with protruding panels are shown to be the most effective. Measurements of the thermal enhancement factor which represents the ratio of heat flux into heat flux out of a channel and numerical simulations of the internal flow velocity field attribute the thermal enhancement resulting in the thermoelectric power improvement to thermal and velocity field synergy

Planning new coal-fired power plants

Energy Technology Data Exchange (ETDEWEB)

Benesch, W.A. [STEAG encotec GmbH, Essen (Germany)

2001-07-01

When considering fossil energy sources, it can be seen that natural gas and oil will become much scarcer than coal. Therefore, one practical option is to investigate and further develop coal-based energy supplies for the future. However, the existing coal stocks must be used very sparingly. Consequently, the conversion efficiency of the chemically-bonded energy in power and heat needs to be improved. By these means, and also by modern environmental engineering, power can be generated from coal without harming the environment. (orig.)

Obtention and characterization of ceramic products with addition of the mineral coal bottom ashes from thermoelectric power plants; Obtencao e caracterizacao de produtos ceramicos com a adicao de cinzas pesadas de carvao mineral provenientes de usinas termeletricas

Energy Technology Data Exchange (ETDEWEB)

Kniess, C.T.; Prates, P.B.; Brys, M.; Martins, G.J.; Riella, H.G., E-mail: kniesscl@gmail.com [Universidade Federal de Santa Catarina (UFSC), SC (Brazil); Bernardin, A. [Universidade do Extremo Sul de Santa Catarina (UNESC), SC (Brazil)

2011-07-01

The physical, chemical and mineralogical properties of mineral coal bottom ash derived from thermoelectric power plants are compatible with various raw materials used in ceramic industries, which indicates a possibility of partial or fully substitution of raw materials by this residue. This work intends to obtain and characterize ceramic products with additions of different percentages of bottom ash coal. For this, was used a commercial ceramic body (CI) made by an industry in the state of Santa Catarina. The formulations of the ceramics products were obtained by the mixture design (planning network Simplex). The byproduct of coal bottom ash was found to be an attractive raw material source of SiO{sub 2} and Al{sub 2}O{sub 3} to obtain ceramic materials. Was demonstrated the possibility of developing a ceramic materials classified as semi-porous (6 10) with additions of up to 20% of coal bottom ash in the composition of the ceramic body. (author)

Modeling passive power generation in a temporally-varying temperature environment via thermoelectrics

International Nuclear Information System (INIS)

Bomberger, Cory C.; Attia, Peter M.; Prasad, Ajay K.; Zide, Joshua M.O.

2013-01-01

This paper presents a model to predict the power generation of a thermoelectric generator in a temporally-varying temperature environment. The model employs a thermoelectric plate sandwiched between two different heat exchangers to convert a temporal temperature gradient in the environment to a spatial temperature gradient within the device suitable for thermoelectric power generation. The two heat exchangers are designed such that their temperatures respond to a change in the environment's temperature at different rates which sets up a temperature differential across the thermoelectric and results in power generation. In this model, radiative and convective heat transfer between the device and its surroundings, and heat flow between the two heat exchangers across the thermoelectric plate are considered. The model is simulated for power generation in Death Valley, CA during the summer using the diurnal variation of air temperature and radiative exchange with the sun and night sky as heat sources and sinks. The optimization of power generation via scaling the device size is discussed. Additional applications of this device are considered. -- Highlights: • Thermoelectric power generation with time-varying temperature is modeled. • The ability to generate power without a natural spatial gradient is demonstrated. • Time dependent heat-transfer and differential heat flow rates are considered. • Optimization of power generation via scaling the device size is discussed

Thermoelectric power of PrMg3

Science.gov (United States)

Isikawa, Yosikazu; Somiya, Kazuya; Koyanagi, Huruto; Mizushima, Toshio; Kuwai, Tomohiko; Tayama, Takashi

2010-01-01

PrMg3 is supposed to be one of the strongly correlated electron systems originated from the hybridization between the Pr 4f and conduction electrons, because the gigantic electronic specific heat coefficient C/T was observed at low temperatures. However, a typical behaviour of - ln T dependence was not observed in the temperature dependence of the electrical resistivity. The thermoelectric power S is a powerful tool to investigate the density of states at the Fermi energy. We measured carefully the thermoelectric power of PrMg3 in the temperature range between 2 and 300 K. S is extremely small, ranged within ±1 μV/K over the whole temperature. The value of S/T at low temperature limit was also significantly smaller than expected from the specific heat results. We therefore conclude that the density of state at the Fermi level is not enhanced in PrMg3.

Thermoelectric power of PrMg3

International Nuclear Information System (INIS)

Isikawa, Yosikazu; Somiya, Kazuya; Koyanagi, Huruto; Mizushima, Toshio; Kuwai, Tomohiko; Tayama, Takashi

2010-01-01

PrMg 3 is supposed to be one of the strongly correlated electron systems originated from the hybridization between the Pr 4f and conduction electrons, because the gigantic electronic specific heat coefficient C/T was observed at low temperatures. However, a typical behaviour of - ln T dependence was not observed in the temperature dependence of the electrical resistivity. The thermoelectric power S is a powerful tool to investigate the density of states at the Fermi energy. We measured carefully the thermoelectric power of PrMg 3 in the temperature range between 2 and 300 K. S is extremely small, ranged within ±1 μV/K over the whole temperature. The value of S/T at low temperature limit was also significantly smaller than expected from the specific heat results. We therefore conclude that the density of state at the Fermi level is not enhanced in PrMg 3 .

ANN-GA based optimization of a high ash coal-fired supercritical power plant

International Nuclear Information System (INIS)

Suresh, M.V.J.J.; Reddy, K.S.; Kolar, Ajit Kumar

2011-01-01

Highlights: → Neuro-genetic power plant optimization is found to be an efficient methodology. → Advantage of neuro-genetic algorithm is the possibility of on-line optimization. → Exergy loss in combustor indicates the effect of coal composition on efficiency. -- Abstract: The efficiency of coal-fired power plant depends on various operating parameters such as main steam/reheat steam pressures and temperatures, turbine extraction pressures, and excess air ratio for a given fuel. However, simultaneous optimization of all these operating parameters to achieve the maximum plant efficiency is a challenging task. This study deals with the coupled ANN and GA based (neuro-genetic) optimization of a high ash coal-fired supercritical power plant in Indian climatic condition to determine the maximum possible plant efficiency. The power plant simulation data obtained from a flow-sheet program, 'Cycle-Tempo' is used to train the artificial neural network (ANN) to predict the energy input through fuel (coal). The optimum set of various operating parameters that result in the minimum energy input to the power plant is then determined by coupling the trained ANN model as a fitness function with the genetic algorithm (GA). A unit size of 800 MWe currently under development in India is considered to carry out the thermodynamic analysis based on energy and exergy. Apart from optimizing the design parameters, the developed model can also be used for on-line optimization when quick response is required. Furthermore, the effect of various coals on the thermodynamic performance of the optimized power plant is also determined.

Reuse of Produced Water from CO₂ Enhanced Oil Recovery, Coal-Bed Methane, and Mine Pool Water by Coal-Based Power Plants

Energy Technology Data Exchange (ETDEWEB)

Knutson, Chad [Univ. of Illinois, Champaign, IL (United States); Dastgheib, Seyed A. [Univ. of Illinois, Champaign, IL (United States); Yang, Yaning [Univ. of Illinois, Champaign, IL (United States); Ashraf, Ali [Univ. of Illinois, Champaign, IL (United States); Duckworth, Cole [Univ. of Illinois, Champaign, IL (United States); Sinata, Priscilla [Univ. of Illinois, Champaign, IL (United States); Sugiyono, Ivan [Univ. of Illinois, Champaign, IL (United States); Shannon, Mark A. [Univ. of Illinois, Champaign, IL (United States); Werth, Charles J. [Univ. of Illinois, Champaign, IL (United States)

2012-07-01

Power generation in the Illinois Basin is expected to increase by as much as 30% by the year 2030, and this would increase the cooling water consumption in the region by approximately 40%. This project investigated the potential use of produced water from CO₂ enhanced oil recovery (CO₂-EOR) operations; coal-bed methane (CBM) recovery; and active and abandoned underground coal mines for power plant cooling in the Illinois Basin. Specific objectives of this project were: (1) to characterize the quantity, quality, and geographic distribution of produced water in the Illinois Basin; (2) to evaluate treatment options so that produced water may be used beneficially at power plants; and (3) to perform a techno-economic analysis of the treatment and transportation of produced water to thermoelectric power plants in the Illinois Basin. Current produced water availability within the basin is not large, but potential flow rates up to 257 million liters per day (68 million gallons per day (MGD)) are possible if CO₂-enhanced oil recovery and coal bed methane recovery are implemented on a large scale. Produced water samples taken during the project tend to have dissolved solids concentrations between 10 and 100 g/L, and water from coal beds tends to have lower TDS values than water from oil fields. Current pretreatment and desalination technologies including filtration, adsorption, reverse osmosis (RO), and distillation can be used to treat produced water to a high quality level, with estimated costs ranging from $2.6 to $10.5 per cubic meter ($10 to $40 per 1000 gallons). Because of the distances between produced water sources and power plants, transportation costs tend to be greater than treatment costs. An optimization algorithm was developed to determine the lowest cost pipe network connecting sources and sinks. Total water costs increased with flow rate up to 26 million liters per day (7 MGD), and the range was from $4 to $16 per cubic meter

Evaluation of high step-up power electronics stages in thermoelectric generator systems

DEFF Research Database (Denmark)

Sun, Kai; Ni, Longxian; Chen, Min

2013-01-01

To develop practical thermoelectric generator (TEG) systems, especially radioisotope thermoelectric power supplies for deep-space exploration, a power conditioning stage with high step-up gain is indispensable. This stage is used to step up the low output voltage of thermoelectric generators...... to the required high level. Furthermore, maximum power point tracking control for TEG modules needs to be implemented into the power electronics stages. In this paper, the temperature-dependent electrical characteristics of a thermoelectric generator are analyzed in depth. Three typical high step-up power...... converters suitable for TEG applications are discussed: an interleaved boost converter, a boost converter with a coupled inductor and an interleaved boost converter with an auxiliary transformer. A general comparison of the three high step-up converters is conducted to study the step-up gain, conversion...

Direct energy balance based active disturbance rejection control for coal-fired power plant.

Science.gov (United States)

Sun, Li; Hua, Qingsong; Li, Donghai; Pan, Lei; Xue, Yali; Lee, Kwang Y

2017-09-01

The conventional direct energy balance (DEB) based PI control can fulfill the fundamental tracking requirements of the coal-fired power plant. However, it is challenging to deal with the cases when the coal quality variation is present. To this end, this paper introduces the active disturbance rejection control (ADRC) to the DEB structure, where the coal quality variation is deemed as a kind of unknown disturbance that can be estimated and mitigated promptly. Firstly, the nonlinearity of a recent power plant model is analyzed based on the gap metric, which provides guidance on how to set the pressure set-point in line with the power demand. Secondly, the approximate decoupling effect of the DEB structure is analyzed based on the relative gain analysis in frequency domain. Finally, the synthesis of the DEB based ADRC control system is carried out based on multi-objective optimization. The optimized ADRC results show that the integrated absolute error (IAE) indices of the tracking performances in both loops can be simultaneously improved, in comparison with the DEB based PI control and H ∞ control system. The regulation performance in the presence of the coal quality variation is significantly improved under the ADRC control scheme. Moreover, the robustness of the proposed strategy is shown comparable with the H ∞ control. Copyright © 2017. Published by Elsevier Ltd.

Heat transfer enhancement of a modularised thermoelectric power generator for passenger vehicles

International Nuclear Information System (INIS)

Li, Bo; Huang, Kuo; Yan, Yuying; Li, Yong; Twaha, Ssennoga; Zhu, Jie

2017-01-01

Highlights: •Shape-adapted thermoelectric module for highly compact heat recovery exchanger assembly. •Heat pipe-assisted heat transfer enhancement method for better power output. •Highest power output ratio to the total volume of heat recovery exchanger. •Cascaded thermoelectric system can be scaled and extended for various power output. •Self-clamping design of thermoelectric module can solve the thermomechanical imbalances. -- Abstract: Transport represents over a quarter of Europe's greenhouse gas emissions and is the leading cause of air pollution in cities. It has not seen the same gradual decline in emissions as other sectors. Recently, the thermoelectric power generation (TEG) technology emerges as an alternative solution to the emission reduction challenge in this area. In this paper, we present an innovative pathway to an improved heat supply into the concentric shape-adapted TEG modules, integrating the heat pipe technologies. It relies on a phase changing approach which enhances the heat flux through the TEG surface. In order to improve the heat transfer for higher efficiency, in our work, the heat pipes are configured in the radial direction of the exhaust streams. The analysis shows that the power output is adequate for the limited space under the chassis of the passenger car. Much effort can also be applied to obtain enhanced convective heat transfer by adjusting the heat pipes at the dual sides of the concentric TEG modules. Heat enhancement at the hot side of the TEG has an effective impact on the total power out of the TEG modules. However, such improvements can be offset by the adjustment made from the coolant side. Predictably, the whole temperature profile of TEG system is subject to the durability and operational limitations of each component. Furthermore, the results highlight the importance of heat transfer versus the TEG power generation under two possible configurations in the passenger car. The highest power output per

Portable Thermoelectric Power Generator Coupled with Phase Change Material

OpenAIRE

Lim Chong C.; Al-Kayiem Hussain H.; Sing Chin Y.

2014-01-01

Solar is the intermittent source of renewable energy and all thermal solar systems having a setback on non-functioning during the night and cloudy environment. This paper presents alternative solution for power generation using thermoelectric which is the direct conversion of temperature gradient of hot side and cold side of thermoelectric material to electric voltage. Phase change material with latent heat effect would help to prolong the temperature gradient across thermoelectric material f...

Benzothienobenzothiophene-Based Molecular Conductors: High Conductivity, Large Thermoelectric Power Factor, and One-Dimensional Instability.

Science.gov (United States)

Kiyota, Yasuhiro; Kadoya, Tomofumi; Yamamoto, Kaoru; Iijima, Kodai; Higashino, Toshiki; Kawamoto, Tadashi; Takimiya, Kazuo; Mori, Takehiko

2016-03-23

On the basis of an excellent transistor material, [1]benzothieno[3,2-b][1]benzothiophene (BTBT), a series of highly conductive organic metals with the composition of (BTBT)2XF6 (X = P, As, Sb, and Ta) are prepared and the structural and physical properties are investigated. The room-temperature conductivity amounts to 4100 S cm(-1) in the AsF6 salt, corresponding to the drift mobility of 16 cm(2) V(-1) s(-1). Owing to the high conductivity, this salt shows a thermoelectric power factor of 55-88 μW K(-2) m(-1), which is a large value when this compound is regarded as an organic thermoelectric material. The thermoelectric power and the reflectance spectrum indicate a large bandwidth of 1.4 eV. These salts exhibit an abrupt resistivity jump under 200 K, which turns to an insulating state below 60 K. The paramagnetic spin susceptibility, and the Raman and the IR spectra suggest 4kF charge-density waves as an origin of the low-temperature insulating state.

Feasibility study of a green energy powered thermoelectric chip based air conditioner for electric vehicles

International Nuclear Information System (INIS)

Miranda, Á.G.; Chen, T.S.; Hong, C.W.

2013-01-01

Traditional compressed-refrigerant air conditioning systems consume substantial energy that may reduce the driving performance and cruising mileage of electric vehicles considerably. It is crucial to design a new climate control system, using a direct energy conversion principle, to further aid in the commercialization of modern electric vehicles. A solid state air conditioner model consisting on TECs (thermoelectric chips) as the load, DSSCs (dye sensitized solar cells) as the renewable energy source and high power LiBs (lithium-ion batteries) as an energy storage device are considered for a personal mobility vehicle. The power management between the main power net and the solid state air conditioner interface is designed with an outer proportional-integral controller and an inner passivity based current controller with a loss included model for perfect tracking. This model is intended to comprise thermal and electrical elements which can be tunable for performance benchmarking and optimization of a solid state air conditioning system. Dynamic performance simulations of the solid-state air conditioner are performed, alongside guidelines for feasibility. - Highlights: • Alternative model extraction for dye sensitized solar cells. • Improved and computationally fast model for the cabin air temperature dynamics. • Euler–Lagrange loss included modeling of a buck converter. • Loss-included passivity based inner loop current control. • The thermoelectric chip air conditioner is tested in simulated cooling/heating scenarios

Perspectives for the coal thermoelectric generation; Perspectivas para a geracao termeletrica a carvao

Energy Technology Data Exchange (ETDEWEB)

Marreco, Juliana de M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Planejamento Energetico; Pereira Junior, Amaro; Tavares, Marina E. [EPE - Empresa de Pesquisa Energetica, Rio de Janeiro, RJ (Brazil)

2006-07-01

This paper presents coal future perspectives on power generation. Based on a global market point of view and on demand scenarios. Positive and negative aspects are analysed: if on one hand it may be the solution for safety energy supply, by the other hand it may jeopardize the environment. Nevertheless, new clean coal technologies are now available overcoming some of these difficulties. Without any bias, the paper objective is to provide data for a fair valuation over the coal expansion on power generation in the world and in Brazil. (author)

Tariff-based incentives for improving coal-power-plant efficiencies in India

International Nuclear Information System (INIS)

Chikkatur, Ananth P.; Sagar, Ambuj D.; Abhyankar, Nikit; Sreekumar, N.

2007-01-01

Improving the efficiency of coal-based power plants plays an important role in improving the performance of India's power sector. It allows for increased consumer benefits through cost reduction, while enhancing energy security and helping reduce local and global pollution through more efficient coal use. A focus on supply-side efficiency also complements other ongoing efforts on end-use efficiency. The recent restructuring of the Indian electricity sector offers an important route to improving power plant efficiency, through regulatory mechanisms that allow for an independent tariff setting process for bulk purchases of electricity from generators. Current tariffs based on normative benchmarks for performance norms are hobbled by information asymmetry (where regulators do not have access to detailed performance data). Hence, we propose a new incentive scheme that gets around the asymmetry problem by setting performance benchmarks based on actual efficiency data, rather than on a normative basis. The scheme provides direct tariff-based incentives for efficiency improvements, while benefiting consumers by reducing electricity costs in the long run. This proposal might also be useful for regulators in other countries to incorporate similar incentives for efficiency improvement in power generation

Enhanced thermoelectric power in two-dimensional transition metal dichalcogenide monolayers

KAUST Repository

Pu, Jiang; Kanahashi, Kaito; Cuong, Nguyen Thanh; Chen, Chang-Hsiao; Li, Lain-Jong; Okada, Susumu; Ohta, Hiromichi; Takenobu, Taishi

2016-01-01

The carrier-density-dependent conductance and thermoelectric properties of large-area MoS2 and WSe2 monolayers are simultaneously investigated using the electrolyte gating method. The sign of the thermoelectric power changes across the transistor

Simultaneous power generation and heat recovery using a heat pipe assisted thermoelectric generator system

International Nuclear Information System (INIS)

Remeli, Muhammad Fairuz; Tan, Lippong; Date, Abhijit; Singh, Baljit; Akbarzadeh, Aliakbar

2015-01-01

Highlights: • A new passive power cogeneration system using industrial waste heat was introduced. • Heat pipes and thermoelectrics were used for recovering waste heat and electricity. • Theoretical model predicted the 2 kW test rig could recover 1.345 kW thermal power. • 10.39 W electrical power was produced equivalent to 0.77% conversion efficiency. - Abstract: This research explores a new method of recovering waste heat and electricity using a combination of heat pipes and thermoelectric generators (HP-TEG). The HP-TEG system consists of Bismuth Telluride (Bi 2 Te 3 ) based thermoelectric generators (TEGs), which are sandwiched between two finned heat pipes to achieve a temperature gradient across the TEG for thermoelectricity generation. A theoretical model was developed to predict the waste heat recovery and electricity conversion performances of the HP-TEG system under different parametric conditions. The modelling results show that the HP-TEG system has the capability of recovering 1.345 kW of waste heat and generating 10.39 W of electrical power using 8 installed TEGs. An experimental test bench for the HP-TEG system is under development and will be discussed in this paper

Combined compressed air storage-low BTU coal gasification power plant

Science.gov (United States)

Kartsounes, George T.; Sather, Norman F.

1979-01-01

An electrical generating power plant includes a Compressed Air Energy Storage System (CAES) fueled with low BTU coal gas generated in a continuously operating high pressure coal gasifier system. This system is used in coordination with a continuously operating main power generating plant to store excess power generated during off-peak hours from the power generating plant, and to return the stored energy as peak power to the power generating plant when needed. The excess coal gas which is produced by the coal gasifier during off-peak hours is stored in a coal gas reservoir. During peak hours the stored coal gas is combined with the output of the coal gasifier to fuel the gas turbines and ultimately supply electrical power to the base power plant.

Lean Maintenance Applied to Improve Maintenance Efficiency in Thermoelectric Power Plants

Directory of Open Access Journals (Sweden)

Orlando Duran

2017-10-01

Full Text Available Thermoelectric power plants consist of a set of critical equipment that require high levels of availability and reliability. Due to this, maintenance of these physical assets is gaining momentum in industry. Maintenance is considered as an activity that contributes to improving the availability, efficiency and productivity of each piece of equipment. Several techniques have been used to achieve greater efficiencies in maintenance, among which we can find the lean maintenance philosophy. Despite the wide diffusion of lean maintenance, there is no structured method that supports the prescription of lean tools applied to the maintenance function. This paper presents the experience gathered in two lean maintenance projects in thermoelectric power plants. The application of lean techniques was based on using a previously developed multicriterial decision making process that uses the Fuzzy Analytic Hierarchy Process (AHP methodology to carry out a diagnosis and prescription tasks. That methodology allowed the prescription of the appropriated lean techniques to resolve the main deficiencies in maintenance function. The results of applying such lean tools show that important results can be obtained, making the maintenance function in thermoelectric power plants more efficient and lean.

A holistic 3D finite element simulation model for thermoelectric power generator element

International Nuclear Information System (INIS)

Wu, Guangxi; Yu, Xiong

2014-01-01

Highlights: • Development of a holistic simulation model for the thermoelectric energy harvester. • Account for delta Seebeck coefficient and carrier charge densities variations. • Solution of thermo-electric coupling problem with finite element method. • Model capable of predicting phenomena not captured by traditional models. • A simulation tool for design of innovative TEM materials and structures. - Abstract: Harvesting the thermal energy stored in the ambient environment provides a potential sustainable energy source. Thermoelectric power generators have advantages of having no moving parts, being durable, and light-weighted. These unique features are advantageous for many applications (i.e., carry-on medical devices, embedded infrastructure sensors, aerospace, transportation, etc.). To ensure the efficient applications of thermoelectric energy harvesting system, the behaviors of such systems need to be fully understood. Finite element simulations provide important tools for such purpose. Although modeling the performance of thermoelectric modules has been conducted by many researchers, due to the complexity in solving the coupled problem, the influences of the effective Seebeck coefficient and carrier density variations on the performance of thermoelectric system are generally neglected. This results in an overestimation of the power generator performance under strong-ionization temperature region. This paper presents an advanced simulation model for thermoelectric elements that considers the effects of both factors. The mathematical basis of this model is firstly presented. Finite element simulations are then implemented on a thermoelectric power generator unit. The characteristics of the thermoelectric power generator and their relationship to its performance are discussed under different working temperature regions. The internal physics processes of the TEM harvester are analyzed from the results of computational simulations. The new model

Theoretical analysis of thermoelectric power of nanocrystalline ReSi2 thin film

International Nuclear Information System (INIS)

Kchoudhary, K; Kaurav; Gupta, N; Varshney, D

2007-01-01

The formulation is developed for the predictive modeling of thermoelectric power (S) of nano-crystalline ReSi 2 . We have evaluated the phonon thermoelectric power by incorporating the scattering of phonons with impurities, grain boundaries, charge careers and phonons. It is noticed that at low temperatures (T < 400 K), S increases and show power temperature dependence because of the larger mean free path of phonon, S shows a broad peak at about 550 K, which is artefact of the competition among umklapp scattering and grain boundaries scattering. Further, by increasing temperature S decreases with change in slope. The anomalies are well accounted in terms of interaction among the phonons-impurity, phonon grain boundaries and the umklapp scattering. Under certain conditions grain boundary scattering is expected to be more effective on heat carrying phonons than on Umklapp scattering, causing an increased thermoelectric power. Numerical analysis of thermoelectric power from the present model shows similar results as those revealed from experiments

Enhanced thermoelectric power in ultrathin topological insulators with magnetic doping

KAUST Repository

Tahir, M.

2014-09-07

We derive analytical expressions for the magnetic moment and orbital magnetization as well as for the corresponding thermal conductivity and thermoelectric power of a topological insulator film. We demonstrate enhancement of the thermoelectric transport for decreasing film thickness and for application of an exchange field due to the tunable band gap. Combining hybridization and exchange field is particularly suitable for heat to electric energy conversion and thermoelectric cooling.

Enhanced thermoelectric power in ultrathin topological insulators with magnetic doping

KAUST Repository

Tahir, M.; Manchon, Aurelien; Schwingenschlö gl, Udo

2014-01-01

We derive analytical expressions for the magnetic moment and orbital magnetization as well as for the corresponding thermal conductivity and thermoelectric power of a topological insulator film. We demonstrate enhancement of the thermoelectric transport for decreasing film thickness and for application of an exchange field due to the tunable band gap. Combining hybridization and exchange field is particularly suitable for heat to electric energy conversion and thermoelectric cooling.

New Technology for Microfabrication and Testing of a Thermoelectric Device for Generating Mobile Electrical Power

Science.gov (United States)

Prasad, Narasimha S.; Taylor, Patrick J.; Trivedi, Sudhir B.; Kutcher, Susan

2012-01-01

Thermoelectric (TE) power generation is an increasingly important power generation technology. Major advantages include: no moving parts, low-weight, modularity, covertness/silence, high power density, low amortized cost, and long service life with minimum or no required maintenance. Despite low efficiency of power generation, there are many specialized needs for electrical power that TE technologies can uniquely and successfully address. Recent advances in thermoelectric materials technology have rekindled acute interest in thermoelectric power generation. We have developed single crystalline n- and p- type PbTe crystals and are also, developing PbTe bulk nanocomposites using PbTe nano powders and emerging filed assisted sintering technology (FAST). We will discuss the materials requirements for efficient thermoelectric power generation using waste heat at intermediate temperature range (6500 to 8500 K). We will present our recent results on production of n- and p- type PbTe crystals and their thermoelectric characterization. Relative characteristics and performance of PbTe bulk single crystals and nano composites for thermoelectric power generation will be discussed.

Advanced Radioisotope Power Systems Segmented Thermoelectric Research

Science.gov (United States)

Caillat, Thierry

2004-01-01

Flight times are long; - Need power systems with >15 years life. Mass is at an absolute premium; - Need power systems with high specific power and scalability. 3 orders of magnitude reduction in solar irradiance from Earth to Pluto. Nuclear power sources preferable. The Overall objective is to develop low mass, high efficiency, low-cost Advanced Radioisotope Power System with double the Specific Power and Efficiency over state-of-the-art Radioisotope Thermoelectric Generators (RTGs).

Thermoelectric power in ionic and electronic mixed conductors

Energy Technology Data Exchange (ETDEWEB)

Kamata, Masahiro; Jin-nouchi, Kenji; Esaka, Takao [Tottori Univ. (Japan). Faculty of Engineering

1996-08-01

In order to study the thermoelectric property of the oxide ionic and electronic mixed conductor of 10 mol% CaO-doped CeO{sub 2} (CDC), a new type of thermocell was prepared, in which platinum electrodes were embedded in the tube-type sample to diminish the large temperature gradient over the electrodes due to the local heat radiation from heating furnace. Using this thermocell, reproducible data were obtained. The thermoelectric power measured in CDC under various oxygen atmospheres (Po{sub 2}) from 1.0 to about 10{sup -15} atm showed that the sign of Seebeck coefficients changed from minus to plus. This variation of Seebeck coefficients vs. Po{sub 2} was well interpreted by considering that (1) the thermoelectric power could be a driving force to make actual and electrochemical oxygen transfer in the mixed conductor and (2) the electrode processes had limiting rates due to slow oxygen diffusion (or oxygen gas exhaustion at the cathode and evolution at the anode). (author)

A simple maximum power point tracker for thermoelectric generators

International Nuclear Information System (INIS)

Paraskevas, Alexandros; Koutroulis, Eftichios

2016-01-01

Highlights: • A Maximum Power Point Tracking (MPPT) method for thermoelectric generators is proposed. • A power converter is controlled to operate on a pre-programmed locus. • The proposed MPPT technique has the advantage of operational and design simplicity. • The experimental average deviation from the MPP power of the TEG source is 1.87%. - Abstract: ThermoElectric Generators (TEGs) are capable to harvest the ambient thermal energy for power-supplying sensors, actuators, biomedical devices etc. in the μW up to several hundreds of Watts range. In this paper, a Maximum Power Point Tracking (MPPT) method for TEG elements is proposed, which is based on controlling a power converter such that it operates on a pre-programmed locus of operating points close to the MPPs of the power–voltage curves of the TEG power source. Compared to the past-proposed MPPT methods for TEGs, the technique presented in this paper has the advantage of operational and design simplicity. Thus, its implementation using off-the-shelf microelectronic components with low-power consumption characteristics is enabled, without being required to employ specialized integrated circuits or signal processing units of high development cost. Experimental results are presented, which demonstrate that for MPP power levels of the TEG source in the range of 1–17 mW, the average deviation of the power produced by the proposed system from the MPP power of the TEG source is 1.87%.

High thermoelectric power factor in two-dimensional crystals of Mo S2

Science.gov (United States)

Hippalgaonkar, Kedar; Wang, Ying; Ye, Yu; Qiu, Diana Y.; Zhu, Hanyu; Wang, Yuan; Moore, Joel; Louie, Steven G.; Zhang, Xiang

2017-03-01

The quest for high-efficiency heat-to-electricity conversion has been one of the major driving forces toward renewable energy production for the future. Efficient thermoelectric devices require high voltage generation from a temperature gradient and a large electrical conductivity while maintaining a low thermal conductivity. For a given thermal conductivity and temperature, the thermoelectric power factor is determined by the electronic structure of the material. Low dimensionality (1D and 2D) opens new routes to a high power factor due to the unique density of states (DOS) of confined electrons and holes. The 2D transition metal dichalcogenide (TMDC) semiconductors represent a new class of thermoelectric materials not only due to such confinement effects but especially due to their large effective masses and valley degeneracies. Here, we report a power factor of Mo S2 as large as 8.5 mW m-1K-2 at room temperature, which is among the highest measured in traditional, gapped thermoelectric materials. To obtain these high power factors, we perform thermoelectric measurements on few-layer Mo S2 in the metallic regime, which allows us to access the 2D DOS near the conduction band edge and exploit the effect of 2D confinement on electron scattering rates, resulting in a large Seebeck coefficient. The demonstrated high, electronically modulated power factor in 2D TMDCs holds promise for efficient thermoelectric energy conversion.

Comprehensive evaluation of coal-fired power plants based on grey relational analysis and analytic hierarchy process

International Nuclear Information System (INIS)

Xu Gang; Yang Yongping; Lu Shiyuan; Li Le; Song Xiaona

2011-01-01

In China, coal-fired power plants are the main supplier of electricity, as well as the largest consumer of coal and water resources and the biggest emitter of SO x , NO x , and greenhouse gases (GHGs). Therefore, it is important to establish a scientific, reasonable, and feasible comprehensive evaluation system for coal-fired power plants to guide them in achieving multi-optimisation of their thermal, environmental, and economic performance. This paper proposes a novel comprehensive evaluation method, which is based on a combination of the grey relational analysis (GRA) and the analytic hierarchy process (AHP), to assess the multi-objective performance of power plants. Unlike the traditional evaluation method that uses coal consumption as a basic indicator, the proposed evaluation method also takes water consumption and pollutant emissions as indicators. On the basis of the proposed evaluation method, a case study on typical 600 MW coal-fired power plants is carried out to determine the relevancy rules among factors including the coal consumption, water consumption, pollutant, and GHG emissions of power plants. This research offers new ideas and methods for the comprehensive performance evaluation of complex energy utilisation systems, and is beneficial to the synthesised consideration of resources, economy, and environment factors in system optimising and policy making. - Research highlights: → We proposed a comprehensive evaluation method for coal-fired power plants. → The method is based on the grey relational analysis (GRA). → The method also introduces the idea of the analytic hierarchy process (AHP). → The method can assess thermal, economic and environmental performance. → The method can play an active role in guiding power plants' improvements.

Comprehensive evaluation of coal-fired power plants based on grey relational analysis and analytic hierarchy process

Energy Technology Data Exchange (ETDEWEB)

Xu Gang, E-mail: xg2008@ncepu.edu.c [Key Lab of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206 (China); Yang Yongping, E-mail: yyp@ncepu.edu.c [Key Lab of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206 (China); Lu Shiyuan; Li Le [Key Lab of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education, School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206 (China); Song Xiaona [Electromechanical Practice Center, Beijing Information Science and Technology University, Beijing (China)

2011-05-15

In China, coal-fired power plants are the main supplier of electricity, as well as the largest consumer of coal and water resources and the biggest emitter of SO{sub x}, NO{sub x}, and greenhouse gases (GHGs). Therefore, it is important to establish a scientific, reasonable, and feasible comprehensive evaluation system for coal-fired power plants to guide them in achieving multi-optimisation of their thermal, environmental, and economic performance. This paper proposes a novel comprehensive evaluation method, which is based on a combination of the grey relational analysis (GRA) and the analytic hierarchy process (AHP), to assess the multi-objective performance of power plants. Unlike the traditional evaluation method that uses coal consumption as a basic indicator, the proposed evaluation method also takes water consumption and pollutant emissions as indicators. On the basis of the proposed evaluation method, a case study on typical 600 MW coal-fired power plants is carried out to determine the relevancy rules among factors including the coal consumption, water consumption, pollutant, and GHG emissions of power plants. This research offers new ideas and methods for the comprehensive performance evaluation of complex energy utilisation systems, and is beneficial to the synthesised consideration of resources, economy, and environment factors in system optimising and policy making. - Research highlights: {yields} We proposed a comprehensive evaluation method for coal-fired power plants. {yields} The method is based on the grey relational analysis (GRA). {yields} The method also introduces the idea of the analytic hierarchy process (AHP). {yields} The method can assess thermal, economic and environmental performance. {yields} The method can play an active role in guiding power plants' improvements.

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)

A power conditioning system for thermoelectric generator based on interleaved Boost converter with MPPT control

DEFF Research Database (Denmark)

Ni, L.-X; Sun, K.; Zhang, L.

2011-01-01

The thermoelectric generation (TEG) system has its special charactristics of high stablility, low voltage and high current output, which is different from PV modules. The power conditioning system and control schemes used in PV applications cannot be directly applied to TEG applications. A power...... conditioning system for TEG based on interleaved Boost converter with maximum power point tracking (MPPT) control is investigated in this paper. Since an internal resistance exists inside TEG modules, an improved perturbation and observation (P&O) MPPT control scheme with power limit is proposed to extract...... maximum power from TEG by matching the load with internal resistance. Since the battery is usually employed as the load for TEG systems, the interleaved Boost converter operates in two different modes for battery charging: before the battery is fully charged, the system outputs the maximum power (MPPT...

Analysis Of Power Characteristics Of Model Thermoelectric Generator TEG Small Modular

Directory of Open Access Journals (Sweden)

Kisman H. Mahmud

2017-04-01

Full Text Available Thermoelectrically Generator TEG can generate electricity from the temperature difference between hot and cold at the junction thermoelectric module with two different semiconductor materials there will be a flow of current through the junction so as to produce a voltage. This principle uses the Seebeck effect thermoelectric generator as a base. By using these principles this research was conducted to determine the potential of the electric energy of the two peltier modules which would be an alternative source for mobile charger using heat from source of methylated. The focus in this research is the testing of the model TEG Thermoelectric Generator Small Modular to generate power with a variety of different materials of 4 namely Bi2Te3 Bismuth Telluride PbTe-Bite CMO and CMO Cascade-32-62S-32-62S Calcium Mangan oxide to use the cold side heat sink and a fan to simulate heat aluminum plate attached to the hot side of the TEG modules with heat source of methylated. Test results on the TEG Small Modular Model for mobile charger output voltage obtained from 2 pieces Bi2Te3 module Bismuth Telluride Peltier strung together a series of 3.01 Volt with amp916T of 22.7 C which produce power of 0.091 Watt.

Reuse of Treated Internal or External Wastewaters in the Cooling Systems of Coal-Based Thermoelectric Power Plants

Energy Technology Data Exchange (ETDEWEB)

Radisav Vidic; David Dzombak; Ming-Kai Hsieh; Heng Li; Shih-Hsiang Chien; Yinghua Feng; Indranil Chowdhury; Jason Monnell

2009-06-30

This study evaluated the feasibility of using three impaired waters - secondary treated municipal wastewater, passively treated abandoned mine drainage (AMD), and effluent from ash sedimentation ponds at power plants - for use as makeup water in recirculating cooling water systems at thermoelectric power plants. The evaluation included assessment of water availability based on proximity and relevant regulations as well as feasibility of managing cooling water quality with traditional chemical management schemes. Options for chemical treatment to prevent corrosion, scaling, and biofouling were identified through review of current practices, and were tested at bench and pilot-scale. Secondary treated wastewater is the most widely available impaired water that can serve as a reliable source of cooling water makeup. There are no federal regulations specifically related to impaired water reuse but a number of states have introduced regulations with primary focus on water aerosol 'drift' emitted from cooling towers, which has the potential to contain elevated concentrations of chemicals and microorganisms and may pose health risk to the public. It was determined that corrosion, scaling, and biofouling can be controlled adequately in cooling systems using secondary treated municipal wastewater at 4-6 cycles of concentration. The high concentration of dissolved solids in treated AMD rendered difficulties in scaling inhibition and requires more comprehensive pretreatment and scaling controls. Addition of appropriate chemicals can adequately control corrosion, scaling and biological growth in ash transport water, which typically has the best water quality among the three waters evaluated in this study. The high TDS in the blowdown from pilot-scale testing units with both passively treated mine drainage and secondary treated municipal wastewater and the high sulfate concentration in the mine drainage blowdown water were identified as the main challenges for blowdown

Life cycle assessment of sewage sludge co-incineration in a coal-based power station.

Science.gov (United States)

Hong, Jingmin; Xu, Changqing; Hong, Jinglan; Tan, Xianfeng; Chen, Wei

2013-09-01

A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

Parametric optimization of thermoelectric elements footprint for maximum power generation

DEFF Research Database (Denmark)

Rezania, A.; Rosendahl, Lasse; Yin, Hao

2014-01-01

The development studies in thermoelectric generator (TEG) systems are mostly disconnected to parametric optimization of the module components. In this study, optimum footprint ratio of n- and p-type thermoelectric (TE) elements is explored to achieve maximum power generation, maximum cost......-performance, and variation of efficiency in the uni-couple over a wide range of the heat transfer coefficient on the cold junction. The three-dimensional (3D) governing equations of the thermoelectricity and the heat transfer are solved using the finite element method (FEM) for temperature dependent properties of TE...... materials. The results, which are in good agreement with the previous computational studies, show that the maximum power generation and the maximum cost-performance in the module occur at An/Ap

High-performance thermoelectric materials based on ternary TiO2/CNT/PANI composites.

Science.gov (United States)

Erden, Fuat; Li, Hui; Wang, Xizu; Wang, FuKe; He, Chaobin

2018-04-04

In the present work, we report the fabrication of high-performance thermoelectric materials using TiO2/CNT/PANI ternary composites. We showed that a conductivity of ∼2730 S cm-1 can be achieved for the binary CNT (70%)/PANI (30%) composite, which is the highest recorded value for the reported CNT/PANI composites. We further demonstrated that the Seebeck coefficient of CNT/PANI composites could be enhanced by incorporating TiO2 nanoparticles into the binary CNT/PANI composites, which could be attributed to lower carrier density and the energy scattering of low-energy carriers at the interfaces of TiO2/a-CNT and TiO2/PANI. The resulting TiO2/a-CNT/PANI ternary system exhibits a higher Seebeck coefficient and enhanced thermoelectric power. Further optimization of the thermoelectric power was achieved by water treatment and by tuning the processing temperature. A high thermoelectric power factor of 114.5 μW mK-2 was obtained for the ternary composite of 30% TiO2/70% (a-CNT (70%)/PANI (30%)), which is the highest reported value among the reported PANI based ternary composites. The improvement of thermoelectric performance by incorporation of TiO2 suggests a promising approach to enhance power factor of organic thermoelectric materials by judicial tuning of the carrier concentration and electrical conductivity.

The power of Indonesian coal

Energy Technology Data Exchange (ETDEWEB)

Rosiak, T. [Duke/Fluor Daniel (United States)

2003-02-01

The paper presents three Indonesian projects carried out by Duke/Fluor Daniel whose unique construction and operation have demonstrated the versatility and value of coal-fired power generation. These are: the construction of units 7 and 8 of the Paiton Private Power Project, a 1230 MW pulverised coal plant in Paiton, East Java; construction of a coal fired generation plant and transmission system to provide power for the expansion of a copper and gold mine on the island of Papua; and construction of four 28 MW pulverized coal units to provide 'heavy lifting' for a new mine at Batu Hijau on the island of Sumbawa. Coal was found to cost less than diesel for power generation. 2 photos.

Improved coal grinding and fuel flow control in thermal power plants

DEFF Research Database (Denmark)

Niemczyk, Piotr; Bendtsen, Jan Dimon

2011-01-01

A novel controller for coal circulation and pulverized coal flow in a coal mill is proposed. The design is based on optimal control theory for bilinear systems with additional integral action. The states are estimated from the grinding power consumption and the amount of coal accumulated in the m......A novel controller for coal circulation and pulverized coal flow in a coal mill is proposed. The design is based on optimal control theory for bilinear systems with additional integral action. The states are estimated from the grinding power consumption and the amount of coal accumulated...... as well as when parameter uncertainties and noise are present. The proposed controller lowers the grinding power consumption while in most cases exhibiting superior performance in comparison with the PID controller....

Large theoretical thermoelectric power factor of suspended single-layer MoS2

International Nuclear Information System (INIS)

Babaei, Hasan; Khodadadi, J. M.; Sinha, Sanjiv

2014-01-01

We have calculated the semi-classical thermoelectric power factor of suspended single-layer (SL)- MoS 2 utilizing electron relaxation times derived from ab initio calculations. Measurements of the thermoelectric power factor of SL-MoS 2 on substrates reveal poor power factors. In contrast, we find the thermoelectric power factor of suspended SL-MoS 2 to peak at ∼2.8 × 10 4 μW/m K 2 at 300 K, at an electron concentration of 10 12 cm −2 . This figure is higher than that in bulk Bi 2 Te 3 , for example. Given its relatively high thermal conductivity, suspended SL-MoS 2 may hold promise for in-plane thin-film Peltier coolers, provided reasonable mobilities can be realized

Status of Shanxi Province's power and coal reserves

International Nuclear Information System (INIS)

Wu, D.C.; Shang, J.Y.

1995-01-01

An introduction to Shanxi's coal reserve, production, transportation utilization, electric power generation and transmission capacities is presented with the intention of providing outsiders a clear understanding of Shanxi's coal and power industries. Quantitative sketches of Shanxi's role in China's energy resource production and power generation are included. The province of Shanxi invites investors to visit Shanxi to gain first-hand knowledge. The authors have also taken the liberty of providing the high points of Shanxi's indigenous sceneries and local customs. They believe that in the future, Shanxi's coal based power development will be one of the principal drivers of China's economic growth

The Research of Utilization Hours of Coal-Fired Power Generation Units Based on Electric Energy Balance

Science.gov (United States)

Liu, Junhui; Yang, Jianlian; Wang, Jiangbo; Yang, Meng; Tian, Chunzheng; He, Xinhui

2018-01-01

With grid-connected scale of clean energy such as wind power and photovoltaic power expanding rapidly and cross-province transmission scale being bigger, utilization hours of coal-fired power generation units become lower and lower in the context of the current slowdown in electricity demand. This paper analyzes the influencing factors from the three aspects of demand, supply and supply and demand balance, and the mathematical model has been constructed based on the electric energy balance. The utilization hours of coal-fired power generation units have been solved considering the relationship among proportion of various types of power installed capacity, the output rate and utilization hours. By carrying out empirical research in Henan Province, the utilization hours of coal-fired units of Henan Province in 2020 has been achieved. The example validates the practicability and the rationality of the model, which can provide a basis for the decision-making for coal-fired power generation enterprises.

Thermoelectric cooling of microelectronic circuits and waste heat electrical power generation in a desktop personal computer

International Nuclear Information System (INIS)

Gould, C.A.; Shammas, N.Y.A.; Grainger, S.; Taylor, I.

2011-01-01

Thermoelectric cooling and micro-power generation from waste heat within a standard desktop computer has been demonstrated. A thermoelectric test system has been designed and constructed, with typical test results presented for thermoelectric cooling and micro-power generation when the computer is executing a number of different applications. A thermoelectric module, operating as a heat pump, can lower the operating temperature of the computer's microprocessor and graphics processor to temperatures below ambient conditions. A small amount of electrical power, typically in the micro-watt or milli-watt range, can be generated by a thermoelectric module attached to the outside of the computer's standard heat sink assembly, when a secondary heat sink is attached to the other side of the thermoelectric module. Maximum electrical power can be generated by the thermoelectric module when a water cooled heat sink is used as the secondary heat sink, as this produces the greatest temperature difference between both sides of the module.

Characteristics and parametric analysis of a novel flexible ink-based thermoelectric generator for human body sensor

DEFF Research Database (Denmark)

Qing, Shaowei; Rezaniakolaei, Alireza; Rosendahl, Lasse Aistrup

2018-01-01

Flexible thermoelectric generator became an attractive technology for its wide use especially for curved surfaces applications. This study proposes design of a flexible thermoelectric generator, which is part of a sensor and supplies required electrical power for human body application...... elements thickness and thermoelectric module row number in a proper range can significantly enhance thermoelectric generator performance. The maximum output power can reach 0.2 μW/cm2, which indicates the proposed design is promising for supplying human body sensors. In addition, the basic optimal design....... The thermoelectric generator module has ink-based thermoelements which are made of nano-carbon bismuth telluride materials. Flexible fins conduct the body heat to the thermoelectric uni-couples, extended fins exchange the heat from the cold side of the thermoelectric generator to the ambient. A fully developed one...

Light-triggered thermoelectric conversion based on a carbon nanotube-polymer hybrid gel.

Science.gov (United States)

Miyako, Eijiro; Nagata, Hideya; Funahashi, Ryoji; Hirano, Ken; Hirotsu, Takahiro

2009-01-01

Lights? Nanotubes? Action! A hydrogel comprising lysozymes, poly(ethylene glycol), phospholipids, and functionalized single-walled carbon nanotubes is employed for light-driven thermoelectric conversion. A photoinduced thermoelectric conversion module based on the hydrogel functions as a novel electric power generator (see image). This concept may find application in various industries, such as robotics and aerospace engineering.

Vulnerability of US thermoelectric power generation to climate change when incorporating state-level environmental regulations

Energy Technology Data Exchange (ETDEWEB)

Liu, Lu; Hejazi, Mohamad; Li, Hongyi; Forman, Barton; Zhang, Xiao

2017-07-10

This study explores the interactions between climate and thermoelectric generation in the U.S. by coupling an Earth System Model with a thermoelectric power generation model. We validated model simulations of power production for selected power plants (~44% of existing thermoelectric capacity) against reported values. In addition, we projected future usable capacity for existing power plants under two different climate change scenarios. Results indicate that climate change alone may reduce average thermoelectric generating capacity by 2%-3% by the 2060s. Reductions up to 12% are expected if environmental requirements are enforced without waivers for thermal variation. This study concludes that the impact of climate change on the U.S. thermoelectric power system is less than previous estimates due to an inclusion of a spatially-disaggregated representation of environmental regulations and provisional variances that temporarily relieve power plants from permit requirements. This work highlights the significance of accounting for legal constructs in which the operation of power plants are managed, and underscores the effects of provisional variances in addition to environmental requirements.

Clean coal technology and advanced coal-based power plants

International Nuclear Information System (INIS)

Alpert, S.B.

1991-01-01

Clean Coal Technology is an arbitrary terminology that has gained increased use since the 1980s when the debate over acid raid issues intensified over emissions of sulfur dioxide and nitrogen oxides. In response to political discussions between Prime Minister Brian Mulroney of Canada and President Ronald Reagan in 1985, the US government initiated a demonstration program by the Department of Energy (DOE) on Clean Coal Technologies, which can be categorized as: 1. precombustion technologies wherein sulfur and nitrogen are removed before combustion, combustion technologies that prevent or lower emissions as coal is burned, and postcombustion technologies wherein flue gas from a boiler is treated to remove pollutants, usually transforming them into solids that are disposed of. The DOE Clean Coal Technology (CCT) program is being carried out with $2.5 billion of federal funds and additional private sector funds. By the end of 1989, 38 projects were under way or in negotiation. These projects were solicited in three rounds, known as Clean Coal I, II, and III, and two additional solicitations are planned by DOE. Worldwide about 100 clean coal demonstration projects are being carried out. This paper lists important requirements of demonstration plants based on experience with such plants. These requirements need to be met to allow a technology to proceed to commercial application with ordinary risk, and represent the principal reasons that a demonstration project is necessary when introducing new technology

Thermoelectric Properties of Two-Dimensional Molybdenum-based MXenes

KAUST Repository

Kim, Hyunho

2017-07-05

MXenes are an interesting class of 2D materials consisting of transition metal carbides and nitrides, which are currently a subject of extensive studies. Although there have been theoretical calculations estimating the thermoelectric properties of MXenes, no experimental measurements have been reported so far. In this report, three compositions of Mo-based MXenes (Mo2CTx, Mo2TiC2Tx, and Mo2Ti2C3Tx) have been synthesized and processed into free-standing binder-free papers by vacuum-assisted filtration, and their electrical and thermoelectric properties are measured. Upon heating to 800 K, these MXene papers exhibit high conductivity and n-type Seebeck coefficient. The thermoelectric power reaches 3.09×10-4 W m-1 K-2 at 803 K for the Mo2TiC2Tx MXene. While the thermoelectric properties of MXenes do not reach that of the best materials, they exceed their parent ternary and quaternary layered carbides. Mo2TiC2Tx shows the highest electrical conductivity in combination with the largest Seebeck coefficient of the three 2D materials studied.

BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

Energy Technology Data Exchange (ETDEWEB)

R. Viswanathan; K. Coleman; R.W. Swindeman; J. Sarver; J. Blough; W. Mohn; M. Borden; S. Goodstine; I. Perrin

2003-10-20

The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to maintain a cost-competitive, environmentally acceptable coal-based electric generation option. High sulfur coals will specifically benefit in this respect by having these advanced materials evaluated in high-sulfur coal firing conditions and from the significant reductions in waste generation inherent in the increased operational efficiency. Second, from a national prospective, the results of this program will enable domestic boiler manufacturers to successfully compete in world markets for building high-efficiency coal-fired power plants.

Maximum Efficiency of Thermoelectric Heat Conversion in High-Temperature Power Devices

Directory of Open Access Journals (Sweden)

V. I. Khvesyuk

2016-01-01

Full Text Available Modern trends in development of aircraft engineering go with development of vehicles of the fifth generation. The features of aircrafts of the fifth generation are motivation to use new high-performance systems of onboard power supply. The operating temperature of the outer walls of engines is of 800–1000 K. This corresponds to radiation heat flux of 10 kW/m2 . The thermal energy including radiation of the engine wall may potentially be converted into electricity. The main objective of this paper is to analyze if it is possible to use a high efficiency thermoelectric conversion of heat into electricity. The paper considers issues such as working processes, choice of materials, and optimization of thermoelectric conversion. It presents the analysis results of operating conditions of thermoelectric generator (TEG used in advanced hightemperature power devices. A high-temperature heat source is a favorable factor for the thermoelectric conversion of heat. It is shown that for existing thermoelectric materials a theoretical conversion efficiency can reach the level of 15–20% at temperatures up to 1500 K and available values of Ioffe parameter being ZT = 2–3 (Z is figure of merit, T is temperature. To ensure temperature regime and high efficiency thermoelectric conversion simultaneously it is necessary to have a certain match between TEG power, temperature of hot and cold surfaces, and heat transfer coefficient of the cooling system. The paper discusses a concept of radiation absorber on the TEG hot surface. The analysis has demonstrated a number of potentialities for highly efficient conversion through using the TEG in high-temperature power devices. This work has been implemented under support of the Ministry of Education and Science of the Russian Federation; project No. 1145 (the programme “Organization of Research Engineering Activities”.

Theoretical and experimental analysis of a solar thermoelectric power generation device based on gravity-assisted heat pipes and solar irradiation

International Nuclear Information System (INIS)

Zhang, Zhe; Li, Wenbin; Kan, Jiangming; Xu, Daochun

2016-01-01

Highlights: • A technical solution to the power supply of wireless sensor networks is presented. • The low voltage produced by device is boosted from around 1 V to more than 4 V. • An output current and voltage of the device is acquired as 343 mA and 1057 mV. • The device provides output power 362.56 mW in no electricity conditions. • The economic value of device is demonstrated. - Abstract: Solar thermoelectric power generation has been widely used to solve the power supply limitation issue for low-power wireless sensors because of its light weight, high reliability, low cost, lack of noise, and environmental friendliness. A solar thermoelectric power generation system based on gravity-assisted heat pipes and solar radiation is devised in this paper, and its behavior is continuously measured in realistic outdoor circumstances. The effects of key parameters, including solar luminous flux, load resistance, a proportional coefficient, and a relative Seebeck coefficient, are analyzed. Related experimental results show that the device can output a voltage of 1057 mV and an electrical current of 343 mA, resulting in an output power of 362.56 mW. With a stable external energy conversion module under aluminous flux of 7.81 × 10"4 lx, the voltage converted from the nature solar radiation is boosted from 1057 mV to 4.40 V, which meets the rated operating voltage of low power consumption components, such as low-power wireless sensors and ZigBee modules. An economic analysis of the system shows that the solar thermoelectric power generation device is both economically and technically competitive when it is applied in a low-voltage wireless sensor network.

High Temperature Thermoelectric Properties of ZnO Based Materials

DEFF Research Database (Denmark)

Han, Li

of the dopants and dopant concentrations, a large power factor was obtainable. The sample with the composition of Zn0.9Cd0.1Sc0.01O obtained the highest zT ∼0.3 @1173 K, ~0.24 @1073K, and a good average zT which is better than the state-of-the-art n-type thermoelectric oxide materials. Meanwhile, Sc-doped Zn......This thesis investigated the high temperature thermoelectric properties of ZnO based materials. The investigation first focused on the doping mechanisms of Al-doped ZnO, and then the influence of spark plasma sintering conditions on the thermoelectric properties of Al, Ga-dually doped Zn......O. Following that, the nanostructuring effect for Al-doped ZnO was systematically investigated using samples with different microstructure morphologies. At last, the newly developed ZnCdO materials with superior thermoelectric properties and thermal stability were introduced as promising substitutions...

Compressive strain induced enhancement in thermoelectric-power-factor in monolayer MoS2 nanosheet

International Nuclear Information System (INIS)

Dimple; Jena, Nityasagar; De Sarkar, Abir

2017-01-01

Strain and temperature induced tunability in the thermoelectric properties in monolayer MoS 2 (ML-MoS 2 ) has been demonstrated using density functional theory coupled to semi-classical Boltzmann transport theory. Compressive strain, in general and uniaxial compressive strain (along the zig-zag direction), in particular, is found to be most effective in enhancing the thermoelectric power factor, owing to the higher electronic mobility and its sensitivity to lattice compression along this direction. Variation in the Seebeck coefficient and electronic band gap with strain is found to follow the Goldsmid–Sharp relation. n-type doping is found to raise the relaxation time-scaled thermoelectric power factor higher than p-type doping and this divide widens with increasing temperature. The relaxation time-scaled thermoelectric power factor in optimally n-doped ML-MoS 2 is found to undergo maximal enhancement under the application of 3% uniaxial compressive strain along the zig-zag direction, when both the ( direct ) electronic band gap and the Seebeck coefficient reach their maximum, while the electron mobility drops down drastically from 73.08 to 44.15 cm 2 V −1 s −1 . Such strain sensitive thermoelectric responses in ML-MoS 2 could open doorways for a variety of applications in emerging areas in 2D-thermoelectrics, such as on-chip thermoelectric power generation and waste thermal energy harvesting. (paper)

Study on the coal mixing ratio optimization for a power plant

Science.gov (United States)

Jin, Y. A.; Cheng, J. W.; Bai, Q.; Li, W. B.

2017-12-01

For coal-fired power plants, the application of blended coal combustion has been a great issue due to the shortage and rising prices of high-rank coal. This paper describes the optimization of blending methods between Xing'an lignite coal, Shaltala lignite coal, Ura lignite coal, and Inner Mongolia bituminous coal. The multi-objective decision-making method based on fuzzy mathematics was used to determine the optimal blending ratio to improve the power plant coal-fired economy.

Parameters of thermoelectric power and electronic structure of Yb-based compounds of YbM2X2(M=Fe,Co,Ni,Cu; X=Si,Ge) type

International Nuclear Information System (INIS)

Levin, E.M.; Kuzhel', B.S.

1990-01-01

Thermoelectric power of Yb-based intermetallic alloys YbM 2 Si 2 (M-Co,Ni,Cu) and YbM 2 Ge 2 (M=Fe,Co,Ni) have been investigated and found to have anomalous low-temperature peaks conditioned by intermediate Yb valency. Calculation of electronic structure parameters performed in frames of the localized Fermi-liquid model using experimental data on the thermoelectric power is in good agreement with results of YbCu 2 Si 2 band structure calculation based on the experimental value of the electronic heat capacity with regard for the (2J+1) - fold Yb 2+ degeneration

Regulation of suspended particulate matter (SPM) in Indian coal-based thermal power plants

Science.gov (United States)

Sengupta, Ishita

Air borne particulate matter, in major Indian cities is at least three times the standard prescribed by the WHO. Coal-based thermal power plants are the major emitters of particulate matter in India. The lack of severe penalty for non-compliance with the standards has worsened the situation and thus calls for an immediate need for investment in technologies to regulate particulate emissions. My dissertation studies the optimal investment decisions in a dynamic framework, for a random sample of forty Indian coal-based power plants to abate particulate emissions. I used Linear Programming to solve the double cost minimization problem for the optimal choices of coal, boiler and pollution-control equipment. A policy analysis is done to choose over various tax policies, which would induce the firms to adopt the energy efficient as well as cost efficient technology. The aim here is to reach the WHO standards. Using the optimal switching point model I show that in a dynamic set up, switching the boiler immediately is always the cost effective option for all the power plants even if there is no policy restriction. The switch to a baghouse depends upon the policy in place. Theoretically, even though an emission tax is considered the most efficient tax, an ash tax or a coal tax can also be considered to be a good substitute especially in countries like India where monitoring costs are very high. As SPM is a local pollutant the analysis here is mainly firm specific.

Fault Detection in Coal Mills used in Power Plants

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Mataji, Babak

2006-01-01

In order to achieve high performance and efficiency of coal-fired power plants, it is highly important to control the coal flow into the furnace in the power plant. This means suppression of disturbances and force the coal mill to deliver the required coal flow, as well as monitor the coal mill...... in order to detect faults in the coal mill when they emerge. This paper deals with the second objective. Based on a simple dynamic model of the energy balance a residual is formed for the coal mill. An optimal unknown input observer is designed to estimate this residual. The estimated residual is following...... tested on measured data of a fault in a coal mill, it can hereby be concluded that this residual is very useful for detecting faults in the coal mill....

Development in Zn4Sb-based thermoelectric materials

DEFF Research Database (Denmark)

Yin, Hao

or thermopower,  the electrical conductivity, the thermal conductivity and T the absolute temperature. The best thermoelectrics are heavily doped semiconductors with high thermoelectric power factors and low thermal conductivities, known as “Phonon Glasses Electrical Crystals”. Zn4Sb3 is one such material......-section. The following part reports the effect of nano-particles on the thermoelectric properties and thermal stability of Zn4Sb3. Though TiO2 nano particles have remarkably enhanced the stability, the thermoelectric performance of all the nano-composites deteriorates. Optimization of the content of the nano...

Metallization for Yb14MnSb11-Based Thermoelectric Materials

Science.gov (United States)

Firdosy, Samad; Li, Billy Chun-Yip; Ravi, Vilupanur; Sakamoto, Jeffrey; Caillat, Thierry; Ewell, Richard C.; Brandon, Erik J.

2011-01-01

Thermoelectric materials provide a means for converting heat into electrical power using a fully solid-state device. Power-generating devices (which include individual couples as well as multicouple modules) require the use of ntype and p-type thermoelectric materials, typically comprising highly doped narrow band-gap semiconductors which are connected to a heat collector and electrodes. To achieve greater device efficiency and greater specific power will require using new thermoelectric materials, in more complex combinations. One such material is the p-type compound semiconductor Yb14MnSb11 (YMS), which has been demonstrated to have one of the highest ZT values at 1,000 C, the desired operational temperature of many space-based radioisotope thermoelectric generators (RTGs). Despite the favorable attributes of the bulk YMS material, it must ultimately be incorporated into a power-generating device using a suitable joining technology. Typically, processes such as diffusion bonding and/or brazing are used to join thermoelectric materials to the heat collector and electrodes, with the goal of providing a stable, ohmic contact with high thermal conductivity at the required operating temperature. Since YMS is an inorganic compound featuring chemical bonds with a mixture of covalent and ionic character, simple metallurgical diffusion bonding is difficult to implement. Furthermore, the Sb within YMS readily reacts with most metals to form antimonide compounds with a wide range of stoichiometries. Although choosing metals that react to form high-melting-point antimonides could be employed to form a stable reaction bond, it is difficult to limit the reactivity of Sb in YMS such that the electrode is not completely consumed at an operating temperature of 1,000 C. Previous attempts to form suitable metallization layers resulted in poor bonding, complete consumption of the metallization layer or fracture within the YMS thermoelement (or leg).

The potential impacts of climate-change policy on freshwater use in thermoelectric power generation

International Nuclear Information System (INIS)

Chandel, Munish K.; Pratson, Lincoln F.; Jackson, Robert B.

2011-01-01

Climate change policy involving a price on carbon would change the mix of power plants and the amount of water they withdraw and consume to generate electricity. We analyze what these changes could entail for electricity generation in the United States under four climate policy scenarios that involve different costs for emitting CO 2 and different technology options for reducing emissions out to the year 2030. The potential impacts of the scenarios on the U.S. electric system are modeled using a modified version of the U.S. National Energy Modeling System and water-use factors for thermoelectric power plants derived from electric utility data compiled by the U.S. Energy Information Administration. Under all the climate-policy scenarios, freshwater withdrawals decline 2-14% relative to a business-as-usual (BAU) scenario of no U.S. climate policy. Furthermore, water use decreases as the price on CO 2 under the climate policies increases. At relatively high carbon prices (>$50/tonne CO 2 ), however, retrofitting coal plants to capture CO 2 increases freshwater consumption compared to BAU in 2030. Our analysis suggests that climate policies and a carbon price will reduce both electricity generation and freshwater withdrawals compared to BAU unless a substantial number of coal plants are retrofitted to capture CO 2 . - Highlights: → We analyze the impact of climate change policy on water use for electricity generation. → Water use decreases with an increase in CO 2 allowance price. → Retrofitting of coal plants with CCS could increase water use considerably.

Power generation costs. Coal - nuclear power

International Nuclear Information System (INIS)

1979-01-01

This supplement volume contains 17 separate chapters investigating the parameters which determine power generation costs on the basis of coal and nuclear power and a comparison of these. A detailed calculation model is given. The complex nature of this type of cost comparison is shown by a review of selected parameter constellation for coal-fired and nuclear power plants. The most favourable method of power generation can only be determined if all parameters are viewed together. One quite important parameter is the load factor, or rather the hours of operation. (UA) 891 UA/UA 892 AMO [de

Radioactivity of coals and ash and slag wastes at coal-fired thermal power plants

Science.gov (United States)

Krylov, D. A.; Sidorova, G. P.

2013-04-01

This paper presents an analysis of published data on the content of radioactive nuclides in coals originating from various coal deposits, and in ash and slag wastes produced at coal-fired thermal power plants, as well as in fly ash emitted from thermal power plants into the atmosphere. Problems related to the use of coals with an elevated content of natural radionuclides (NRNs) and methods of their solution implemented at the Urtuyskoe coalfield are dealt with. Data on the analysis of Transbaikal coals for the NRN content, as well as weighted mean content of uranium and thorium in coals from the Siberian Region, are given. In order to reduce irradiation of plant personnel and the population of the areas where coal producers and coal-fired thermal power plants are located, it is necessary to organize very careful control of the NRN content in both coals and products of their combustion that are released into the environment. To solve the problem related to the control of radioactivity, the centralized approach and creation of a proper normative base are needed. Experience gained in developing the Urtuyskoe coalfield shows that it is possible to create an efficient system of coal quality control with respect to the radiation hygiene factor and provide protection of the environment and health of the population.

Impact of proximity of thermoelectric power plants on bronchial obstructive crisis rates

Directory of Open Access Journals (Sweden)

Tamara Ugarte-Avilés

2017-01-01

Full Text Available Abstract Background Environmental pollution is a risk factor for cardiorespiratory diseases. Energy generated by thermoelectric power plants (TEPP represents a relevant source of pollution. The aim of this study was to evaluate the relationship between living near a coal-fired TEPP and the consultation rates for bronchial obstructive crises (BOC in the province of Concepción, Chile. Methods Population-based study. The epidemiological weeks from 2012 to 2014 were analyzed. The dependent variable was the emergency consultation rate for BOC in two health centers within 5 km of a TEPP (Coronel and two that were more than 40 Km away from a TEPP (Talcahuano. The independent variables were the commune, climatological variables (air temperature and relative atmospheric humidity, environmental pollutants (PM10, PM2.5 and nitrogen oxide, weeks with the highest consultation rate and the years. Rates, Pearson’s correlation and gross risk measures were calculated and adjusted for environmental and climatological variables. Results BOC rates were significantly higher in Coronel (RR = 4.9 95% CI 4.0–5.8; p < 0.05. The PM2.5 it showed the strongest correlation with BOC rates (r = 0.3; p < 0.01 in Coronel, but not Talcahuano. Linear regression modelling indicated that proximity to a TEPP (health center location and temperature explained 26 and 18% of the variance in BOC rates, respectively. Conclusions Rates of emergency consultation for BOC were significantly higher among a population living within 5 km of a coal-fired TEPP than those living 40 km away.

A Comparative case study of remote area power supply systems using photovoltaic-battery vs thermoelectric-battery configuration

NARCIS (Netherlands)

Tan, Lippong; Date, Abhijit; Zhang, Bingjie; Singh, Baljit; Ganguly, Sayantan

The paper presents a comparative study of two types of remote area power supply (RAPS) systems, which are the existing photovoltaic-based (PV) configuration and the proposed thermoelectric-based (TE) configuration. Both RAPS systems are solar-based power generators and sized according to Melbourne

CO2 reduction potential of future coal gasification based power generation technologies

International Nuclear Information System (INIS)

Jansen, D.; Oudhuis, A.B.J.; Van Veen, H.M.

1992-03-01

Assessment studies are carried out on coal gasification power plants integrated with gas turbines (IGCC) or molten carbonate fuel cells (MCFC) without and with CO 2 -removal. System elements include coal gasification, high-temperature gas-cleaning, molten carbonate fuel cells or gas turbines, CO shift, membrane separation, CO 2 recovery and a bottoming cycle. Various system configurations are evaluated on the basis of thermodynamic computations. The energy balances of the various system configurations clearly indicate that integrated coal gasification MCFC power plants (IGMCFC) with CO 2 removal have high efficiencies (42-47% LHV) compared to IGCC power plants with CO 2 -removal (33-38% LHV) and that the CO 2 -removal is simplified due to the specific properties of the molten carbonate fuel cells. IGMCFC is therefore an option with future prospective in the light of clean coal technologies for power generation with high energy efficiencies and low emissions. 2 figs., 3 tabs., 10 refs

The world behind electricity from coal. The dubious origin of coal for Dutch coal-fired power plants

International Nuclear Information System (INIS)

2008-01-01

Five energy companies in the Netherlands want to build additional coal-fired power plants: Essent and Nuon, the German company RWE and E.ON and the Belgian company Electrabel. Coal-fired power plants emit 70 percent more CO2 than gas-fired power plants. Especially because of the threat to the climate Greenpeace believes that no more coal-fired power plants should be built. In this publication Greenpeace explores the pollution, the working conditions and human rights with regard to the exploitation of coal. That has been elaborated for the three countries from which Dutch energy companies import coal: South Africa, Colombia and Indonesia. In addition to information about the origin of coal also insight is given into the coal market (stocks and use), the enormous coal transport and the world trade [nl

MHD power station with coal gasification

International Nuclear Information System (INIS)

Brzozowski, W.S.; Dul, J.; Pudlik, W.

1976-01-01

A description is given of the proposed operating method of a MHD-power station including a complete coal gasification into lean gas with a simultaneous partial gas production for the use of outside consumers. A comparison with coal gasification methods actually being used and full capabilities of power stations heated with coal-derived gas shows distinct advantages resulting from applying the method of coal gasification with waste heat from MHD generators working within the boundaries of the thermal-electric power station. (author)

High-performance nanostructured thermoelectric generators for micro combined heat and power systems

International Nuclear Information System (INIS)

Zhang, Yanliang; Wang, Xiaowei; Cleary, Martin; Schoensee, Luke; Kempf, Nicholas; Richardson, Joseph

2016-01-01

Highlights: • A TEG is fabricated using high-efficiency nanostructured thermoelectric materials. • The TEG produces high power density of 2.1 W/cm"2 with 5.3% electrical efficiency. • A micro-CHP system is demonstrated by integrating the TEG into a gas-fired boiler. - Graphical Abstract: - Abstract: Micro combined heat and power (micro-CHP) systems are promising pathways to increase power generation efficiencies. Here a new class of micro-CHP system without moving parts is experimentally demonstrated by integrating high-temperature thermoelectric generators (TEGs) and residential gas-fired boilers, thus enabling wide applications. The TEGs fabricated using high-efficiency nanostructured bulk half-Heusler alloys generate ultrahigh power density of 2.1 W/cm"2 with 5.3% electrical efficiency under 500 °C temperature differences between the hot and cold sides. The TEG system harnesses the untapped exergy between the combustion gas and water, and converts thermal energy into electric power with 4% heat-to-electricity efficiency based on the total heat input into the TEGs. The high-performance TEGs open lots of opportunities to transform power generation technologies and improve energy efficiency.

Exergy analysis of a coal/biomass co-hydrogasification based chemical looping power generation system

International Nuclear Information System (INIS)

Yan, Linbo; Yue, Guangxi; He, Boshu

2015-01-01

Power generation from co-utilization of coal and biomass is very attractive since this technology can not only save the coal resource but make sufficient utilization of biomass. In addition, with this concept, net carbon discharge per unit electric power generation can also be sharply reduced. In this work, a coal/biomass co-hydrogasification based chemical looping power generation system is presented and analyzed with the assistance of Aspen Plus. The effects of different operating conditions including the biomass mass fraction, R_b, the hydrogen recycle ratio, R_h_r, the hydrogasification pressure, P_h_g, the iron to fuel mole ratio, R_i_f, the reducer temperature, T_r_e, the oxidizer temperature, T_o_x, and the fuel utilization factor, U_f of the SOFC (solid oxide fuel cell) on the system operation results including the energy efficiency, η_e, the total energy efficiency, η_t_e, the exergy efficiency, η_e_x, the total exergy efficiency, η_t_e_x and the carbon capture rate, η_c_c, are analyzed. The energy and exergy balances of the whole system are also calculated and the corresponding Sankey diagram and Grassmann diagram are drawn. Under the benchmark condition, exergy efficiencies of different units in the system are calculated. η_t_e, η_t_e_x and η_c_c of the system are also found to be 43.6%, 41.2% and 99.1%, respectively. - Highlights: • A coal/biomass co-hydrogasification based chemical looping power generation system is setup. • Sankey and Grassmann diagrams are presented based on the energy and exergy balance calculations. • Sensitivity analysis is done to understand the system operation characteristics. • Total energy and exergy efficiencies of this system can be 43.6% and 41.2%, respectively. • About 99.1% of the carbon contained in coal and biomass can be captured in this system.

Flexo-green Polypyrrole – Silver nanocomposite films for thermoelectric power generation

International Nuclear Information System (INIS)

Bharti, Meetu; Singh, Ajay; Samanta, Soumen; Debnath, A.K.; Aswal, D.K.; Muthe, K.P.; Gadkari, S.C.

2017-01-01

Graphical abstract: Flexible PPy-Ag films prepared via environment friendly photo-polymerization in aqueous medium exhibited a record figure-of-merit of ∼7.4 × 10 −3 at 335 K among reported PPy based composites due to unique combination of high electrical and low thermal conductivity with increasing content of Ag nanoparticles. A proto-type thermoelectric power generator exhibiting output voltage of 6 mV has been demonstrated using these flexible PPy-Ag films. - Highlights: • Polypyrrole-silver (PPy-Ag) nanocomposites films were prepared on flexible BOPET sheet. • Ag particles anchored between PPy chains improve electrical transport but suppress thermal transport. • This work demonstrates highest figure-of-merit (∼7.4 × 10 −3 at 335 K) among PPy based materials. • A prototype thermoelectric power generator exhibiting output voltage of 6 mV has been fabricated using PPy-Ag films. - Abstract: Conducting polymers offer various advantages over inorganic thermoelectric materials such as eco-friendliness, a reduced manufacturing cost, flexibility, low thermal conductivity and amenability to tuning of electrical properties through doping; have recently drawn much attention for conversion of low temperature waste heat (≤150 °C) into electricity. In this study, we investigated the thermoelectric properties of hybrid films of polypyrrole and silver (PPy-Ag). These films were prepared on biaxially oriented polyethylene terephthalate (BOPET) flexible substrates by eco-friendly one pot photo-polymerization method using aqueous solution of silver nitrate (AgNO 3 ) as photo initiator. Detailed characterization of the samples revealed that morphology of composite films reorganized with the change in AgNO 3 concentration during synthesis. Increasing AgNO 3 concentrations resulted in PPy films containing Ag nanoparticles, nanoclusters as well as macroclusters. With alteration in concentration and size of Ag particles in PPy matrix, it has been observed that the

Study of the solubility of iron in zirconium by thermoelectric power measurements

International Nuclear Information System (INIS)

Borrelly, R.; Merle, P.; Adami, L.; Centre National de la Recherche Scientifique, 69 - Villeurbanne

1990-01-01

Thermoelectric power (TEP) measurements are used to determine the solubility of iron in α-zirconium. A preliminary study shows that TEP is very sensitive to elements in solid solution, to cold-working and to the texture due to rolling in a temperature range including room temperature which is choosen for thermoelectric power measurements. The solutioning of iron obtained by a homogenization treatment and water-quench leads to a decrease of thermoelectric power. The conditions of homogenization treatments such that TEP variations are only due to the variation of iron content in solid solution have been determined. From these results the solubility of iron α-zirconium as a function of temperature has been determined. Moreover, the α-domain of the Zr-rich part of the Zr-Fe diagram has been completely delimited. A micrographic study has been made to confirm these results. (orig.)

The economics of coal power generation in China

International Nuclear Information System (INIS)

Zhao, Changhong; Zhang, Weirong; Wang, Yang; Liu, Qilin; Guo, Jingsheng; Xiong, Minpeng; Yuan, Jiahai

2017-01-01

The Chinese government recently released the 13th FYP (five-year plan) power development plan and proposed a capacity installation target of 1100 GW for coal power. Considering the weak demand growth of coal power since 2014, continuous decline in the annual utilisation hour and the coming market competition, such a planning target is unwelcome and could further the economic deterioration of coal power. In this paper, we employ LCOE (levelised cost of electricity) and project evaluation models to conduct a nationwide survey on the economics of coal power. The economic analysis has clearly indicated that the recent boom of coal power investment in China, which is absurd in many perspectives, is largely the aftermath of uncompleted market reform in the power sector. However, the fundamentals of electricity demand and supply are changing at a speed beyond the imagination of power generators and have foreboded a gloomy prospect for coal power. Our study shows that by 2020, with several exceptions, in most provinces the internal rate of return for coal power will drop below the social average return rate or will even be negative. In this regard, the 13th FYP capacity planning target for coal power is economically untenable and requires radical revision. - Highlights: • Conduct a first-of-its-kind nationwide economic analysis for coal power in China. • Distorted price by improper regulation is the root of investment bubble since 2014. • Cost uplift and market competition foretell a gloomy prospect of coal power. • The 1100 GW capacity planning target for coal power should be abandoned.

Water vulnerabilities for existing coal-fired power plants.

Energy Technology Data Exchange (ETDEWEB)

Elcock, D.; Kuiper, J.; Environmental Science Division

2010-08-19

evaluated. The first type consisted of geographical areas where specific conditions can generate demand vulnerabilities. These conditions include high projected future water consumption by thermoelectric power plants, high projected future water consumption by all users, high rates of water withdrawal per square mile (mi{sup 2}), high projected population increases, and areas projected to be in a water crisis or conflict by 2025. The second type of demand indicator was plant specific. These indicators were developed for each plant and include annual water consumption and withdrawal rates and intensities, net annual power generation, and carbon dioxide (CO{sub 2}) emissions. The supply indictors, which are also area based, include areas with low precipitation, high temperatures, low streamflow, and drought. The indicator data, which were in various formats (e.g., maps, tables, raw numbers) were converted to a GIS format and stored, along with the individual plant data from the CPPDB, in a single GIS database. The GIS database allowed the indicator data and plant data to be analyzed and visualized in any combination. To determine the extent to which a plant would be considered 'vulnerable' to a given demand or supply concern (i.e., that the plant's operations could be affected by water shortages represented by a potential demand or supply indicator), criteria were developed to categorize vulnerability according to one of three types: major, moderate, or not vulnerable. Plants with at least two major demand indicator values and/or at least four moderate demand indicator values were considered vulnerable to demand concerns. By using this approach, 144 plants were identified as being subject to demand concerns only. Plants with at least one major supply indicator value and/or at least two moderate supply indicator values were considered vulnerable to supply concerns. By using this approach, 64 plants were identified as being subject to supply concerns only. In

Power Generation from Coal 2010

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

Coal is the biggest single source of energy for electricity production and its share is growing. The efficiency of converting coal into electricity matters: more efficient power plants use less fuel and emit less climate-damaging carbon dioxide. This book explores how efficiency is measured and reported at coal-fired power plants. With many different methods used to express efficiency performance, it is often difficult to compare plants, even before accounting for any fixed constraints such as coal quality and cooling-water temperature. Practical guidelines are presented that allow the efficiency and emissions of any plant to be reported on a common basis and compared against best practice. A global database of plant performance is proposed that would allow under-performing plants to be identified for improvement. Armed with this information, policy makers would be in a better position to monitor and, if necessary, regulate how coal is used for power generation. The tools and techniques described will be of value to anyone with an interest in the more sustainable use of coal.

A note on the electrochemical nature of the thermoelectric power

Science.gov (United States)

Apertet, Y.; Ouerdane, H.; Goupil, C.; Lecoeur, Ph.

2016-04-01

While thermoelectric transport theory is well established and widely applied, it is not always clear in the literature whether the Seebeck coefficient, which is a measure of the strength of the mutual interaction between electric charge transport and heat transport, is to be related to the gradient of the system's chemical potential or to the gradient of its electrochemical potential. The present article aims to clarify the thermodynamic definition of the thermoelectric coupling. First, we recall how the Seebeck coefficient is experimentally determined. We then turn to the analysis of the relationship between the thermoelectric power and the relevant potentials in the thermoelectric system: As the definitions of the chemical and electrochemical potentials are clarified, we show that, with a proper consideration of each potential, one may derive the Seebeck coefficient of a non-degenerate semiconductor without the need to introduce a contact potential as seen sometimes in the literature. Furthermore, we demonstrate that the phenomenological expression of the electrical current resulting from thermoelectric effects may be directly obtained from the drift-diffusion equation.

Modeling of Thermoelectric Generator Power Characteristics for Motorcycle-Type Engines

Science.gov (United States)

Osipkov, Alexey; Poshekhonov, Roman; Arutyunyan, Georgy; Basov, Andrey; Safonov, Roman

2017-10-01

Thermoelectric generation in vehicles such as motorcycles, all-terrain vehicles, and snowmobiles opens the possibility of additional electrical energy generation by means of exhaust heat utilization. This is beneficial because replacing the mechanical generator used in such vehicles with a more powerful one in cases of electrical power deficiency is impossible. This paper proposes a calculation model for the thermoelectric generator (TEG) operational characteristics of the low-capacity internal combustion engines used in these vehicles. Two TEG structures are considered: (1) TEG with air cooling and (2) TEG with water cooling. Modeling consists of two calculation stages. In the first stage, the heat exchange coefficients of the hot and cold exchangers are determined using computational fluid dynamics. In the second stage, the TEG operational characteristics are modeled based on the nonlinear equations of the heat transfer and power balance. On the basis of the modeling results, the dependence of the TEG's major operating characteristics (such as the electrical power generated by the TEG and its efficiency and mass) on operating conditions or design parameters is determined. For example, the electrical power generated by a TEG for a Yamaha WR450F motorcycle engine with a volume of 0.449 × 10-3 m3 was calculated to be as much as 100 W. Use of the TEG arrangements proposed is justified by the additional electrical power generation for small capacity vehicles, without the need for internal combustion engine redesign.

Large theoretical thermoelectric power factor of suspended single-layer MoS{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Babaei, Hasan, E-mail: babaei@illinois.edu, E-mail: babaei@auburn.edu [Mechanical Science and Engineering Department, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801-2906 (United States); Mechanical Engineering Department, Auburn University, Auburn, Alabama 36849-5341 (United States); Khodadadi, J. M. [Mechanical Engineering Department, Auburn University, Auburn, Alabama 36849-5341 (United States); Sinha, Sanjiv [Mechanical Science and Engineering Department, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801-2906 (United States)

2014-11-10

We have calculated the semi-classical thermoelectric power factor of suspended single-layer (SL)- MoS{sub 2} utilizing electron relaxation times derived from ab initio calculations. Measurements of the thermoelectric power factor of SL-MoS{sub 2} on substrates reveal poor power factors. In contrast, we find the thermoelectric power factor of suspended SL-MoS{sub 2} to peak at ∼2.8 × 10{sup 4} μW/m K{sup 2} at 300 K, at an electron concentration of 10{sup 12} cm{sup −2}. This figure is higher than that in bulk Bi{sub 2}Te{sub 3}, for example. Given its relatively high thermal conductivity, suspended SL-MoS{sub 2} may hold promise for in-plane thin-film Peltier coolers, provided reasonable mobilities can be realized.

Is There Any Future For Coal Power Plants In Europe?

Directory of Open Access Journals (Sweden)

A. V. Zimakov

2017-01-01

Full Text Available The article deals with the policies of EU countries towards coal power plants as well as practical steps taken by their governments. Coal power plants are widely considered to be environmentally harmful which confronts with environmental policies of the EU suggesting Europe-wide cuts of greenhouse gas emissions. Based on that assumption a number of EU countries such asBelgium,Austria,Portugal,Dania,Finland,SwedenandUKare striving to phase out coal power plants and achieved significant progress on this path replacing coal with other generation sources. On the other hand, other EU members are lagging behind as coal phase-out is not an urgent item of their political agenda. This situation is typical forIreland,Netherlands,Italy,Croatia,SloveniaandSlovakia. Domestic coal extracting industry can pose a significant hindering factor for a coal power plants phase-out and can effectively block the process. This is the case inBulgaria,Romania,Hungary,CzechRepublic,GreeceandPoland. ButGermany, which also has a well-developed coal industry, transforms its energy sector towards a green one cutting the share of coal in the generation mix. If this effort of the German government proves successful it will deliver a positive transformation model for other EU countries with a large share of coal in generation-mix due to domestic coal extraction industry. The analysis of the political and economic (both macro and micro processes leads to conclusion that there is no unity among EU member states in their approach towards coal fired power plants phase-out. This will allow for coal power plants to retain their market share in a short to medium term. But in the longer run one can expect a significant decrease of coal fired generation inEurope, even in the countries traditionally dependent on coal.

Development of thermoelectric power generation system utilizing heat of combustible solid waste

International Nuclear Information System (INIS)

Kajikawa, T.; Ito, M.; Katsube, I.; Shibuya, E.

1994-01-01

The paper presents the development of thermoelectric power generation system utilizing heat of municipal solid waste. The systematic classification and design guideline are proposed in consideration of the characteristics of solid waste processing system. The conceptual design of thermoelectric power generation system is carried out for a typical middle scale incinerator system (200 ton/day) by the local model. Totally the recovered electricity is 926.5 kWe by 445 units (569,600 couples). In order to achieve detailed design, one dimensional steady state model taking account of temperature dependency of the heat transfer performance and thermoelectric properties is developed. Moreover, small scale on-site experiment on 60 W class module installed in the real incinerator is carried out to extract various levels of technological problems. In parallel with the system development, high temperature thermoelectric elements such as Mn-Si and so on are developed aiming the optimization of ternary compound and high performance due to controlled fine-grain boundary effect. The manganese silicide made by shrinking-rate controlled sintering method performs 5 (μW/cm K2) in power factor at 800 K. copyright 1995 American Institute of Physics

Quantum Coherent Three-Terminal Thermoelectrics: Maximum Efficiency at Given Power Output

Directory of Open Access Journals (Sweden)

Robert S. Whitney

2016-05-01

Full Text Available This work considers the nonlinear scattering theory for three-terminal thermoelectric devices used for power generation or refrigeration. Such systems are quantum phase-coherent versions of a thermocouple, and the theory applies to systems in which interactions can be treated at a mean-field level. It considers an arbitrary three-terminal system in any external magnetic field, including systems with broken time-reversal symmetry, such as chiral thermoelectrics, as well as systems in which the magnetic field plays no role. It is shown that the upper bound on efficiency at given power output is of quantum origin and is stricter than Carnot’s bound. The bound is exactly the same as previously found for two-terminal devices and can be achieved by three-terminal systems with or without broken time-reversal symmetry, i.e., chiral and non-chiral thermoelectrics.

Relative population exposures from coal-fired and nuclear power plants in India

Energy Technology Data Exchange (ETDEWEB)

Ramachandran, T.V.; Lalit, B.Y.; Mishra, U.C.

1987-01-01

Coal combustion for electric power generation results in dispersal of fly ash, and hence an additional radiation dose to the population living in the neighbourhood of the coal-fired power plants due to natural radioactivity present in coal. The radiation hazards of coal based and nuclear power plants operating in India are given. The dose commitments to the population living within an 88.5 km radius of the thermal and nuclear power plants in India have been computed using the method outlined in an ORNL report. The estimated dose rates for these two types of power plant were compared. The present study shows that the radiation dose from coal-fired and nuclear power plants are comparable.

Nano-mineralogical investigation of coal and fly ashes from coal-based captive power plant (India): An introduction of occupational health hazards

International Nuclear Information System (INIS)

Oliveira, Marcos L.S.; Marostega, Fabiane; Taffarel, Silvio R.; Saikia, Binoy K.; Waanders, Frans B.; DaBoit, Kátia; Baruah, Bimala P.

2014-01-01

Coal derived nano-particles has been received much concern recently around the world for their adverse effects on human health and the environment during their utilization. In this investigation the mineral matter present in some industrially important Indian coals and their ash samples are addressed. Coal and fly ash samples from the coal-based captive power plant in Meghalaya (India) were collected for different characterization and nano-mineralogy studies. An integrated application of advanced characterization techniques such as X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/(Energy Dispersive Spectroscopy) EDS/(selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM)/EDS analysis, and Mössbauer spectroscopy were used to know their extent of risks to the human health when present in coal and fly ash. The study has revealed that the coals contain mainly clay minerals, whilst glass fragments, spinel, quartz, and other minerals in lesser quantities were found to be present in the coal fly ash. Fly ash carbons were present as chars. Indian coal fly ash also found to contain nanominerals and ultrafine particles. The coal-fired power plants are observed to be the largest anthropogenic source of Hg emitted to the atmosphere and expected to increase its production in near future years. The Multi Walled Carbon Nano-Tubes (MWCNTs) are detected in our fly ashes, which contains residual carbonaceous matter responsible for the Hg capture/encapsulation. This detailed investigation on the inter-relationship between the minerals present in the samples and their ash components will also be useful for fulfilling the clean coal technology principles. - Highlights: • We research changes in the level of ultrafine and nanoparticles about coal–ash quality. • Increasing dates will increase human health quality in this Indian coal area. • Welfare effects depend on ex-ante or ex-post assumptions about

Technology Efficiency Study on Nuclear Power and Coal Power in Guangdong Province Based on DEA

International Nuclear Information System (INIS)

Yinong Li; Dong Wang

2006-01-01

Guangdong Province has taken the lead in embarking on nuclear power development to resolve its dire lack of primary resources. With the deepening of the on-going structural reform in the electric power sector in China, the market competition scheme is putting electricity generation enterprises under severe strain. Consequently, it is incumbent upon the nuclear power producers to steadily upgrade management, enhance technical capabilities, reduce cost and improve efficiency. At present, gradual application of such efficiency evaluation methodology has already commenced in some sectors in China including the electric power industry. The purpose of this paper is to use the Data Envelopment Analysis (DEA), which is a cutting-edge approach in the efficiency evaluation field - to study the technological efficiency between nuclear power and coal power in Guangdong Province. The DEA results demonstrate that, as far as Guangdong Province is concerned, the technological efficiency of nuclear power is higher than that of coal power in terms of Technological Efficiency (TE), Pure Technology Efficiency (PTE) and Scale Efficiency (SE). The reason is that nuclear power technology is advanced with a much higher equipment availability factor. Under the same scale, the generation output of nuclear power is far higher than that of equivalent coal power generation. With the environmental protection and sustainable development requirements taken into full account, nuclear power constitutes a clean, safe and highly-efficient energy form which should be extensively harnessed in Guangdong Province to fuel its future continuing economic growth. (authors)

Prototype Combined Heater/Thermoelectric Power Generator for Remote Applications

Science.gov (United States)

Champier, D.; Favarel, C.; Bédécarrats, J. P.; Kousksou, T.; Rozis, J. F.

2013-07-01

This study presents a prototype thermoelectric generator (TEG) developed for remote applications in villages that are not connected to the electrical power grid. For ecological and economic reasons, there is growing interest in harvesting waste heat from biomass stoves to produce some electricity. Because regular maintenance is not required, TEGs are an attractive choice for small-scale power generation in inaccessible areas. The prototype developed in our laboratory is especially designed to be implemented in stoves that are also used for domestic hot water heating. The aim of this system is to provide a few watts to householders, so they have the ability to charge cellular phones and radios, and to get some light at night. A complete prototype TEG using commercial (bismuth telluride) thermoelectric modules has been built, including system integration with an electric DC/DC converter. The DC/DC converter has a maximum power point tracker (MPPT) driven by an MC9SO8 microcontroller, which optimizes the electrical energy stored in a valve-regulated lead-acid battery. Physical models were used to study the behavior of the thermoelectric system and to optimize the performance of the MPPT. Experiments using a hot gas generator to simulate the exhaust of the combustion chamber of a stove are used to evaluate the system. Additionally, potential uses of such generators are presented.

BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

Energy Technology Data Exchange (ETDEWEB)

R. Viswanathan; K. Coleman

2003-01-20

The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. In the 21st century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while at the same time preserving environmental values. Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios. The use of coal for electricity generation poses a unique set of challenges. On the one hand, coal is plentiful and available at low cost in much of the world, notably in the U.S., China, and India. Countries with large coal reserves will want to develop them to foster economic growth and energy security. On the other hand, traditional methods of coal combustion emit pollutants and CO{sub 2} at high levels relative to other generation options. Maintaining coal as a generation option in the 21st century will require methods for addressing these environmental issues. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to

Dustfall design of open coal yard in the power plant-a case study on the closed reconstruction project of coal storage yard in shengli power plant

Science.gov (United States)

Wang, Kunpeng; Ji, Weidong; Zhang, Feifei; Yu, Wei; Zheng, Runqing

2018-02-01

This thesis, based on the closed reconstruction project of the coal storage yard of Shengli Power Plant which is affiliated to Sinopec Shengli Petroleum Administration, first makes an analysis on the significance of current dustfall reconstruction of open coal yard, then summarizes the methods widely adopted in the dustfall of large-scale open coal storage yard of current thermal power plant as well as their advantages and disadvantages, and finally focuses on this project, aiming at providing some reference and assistance to the future closed reconstruction project of open coal storage yard in thermal power plant.

Thermoelectric Power Generation Utilizing the Waste Heat from a Biomass Boiler

Science.gov (United States)

Brazdil, Marian; Pospisil, Jiri

2013-07-01

The objective of the presented work is to test the possibility of using thermoelectric power to convert flue gas waste heat from a small-scale domestic pellet boiler, and to assess the influence of a thermoelectric generator on its function. A prototype of the generator, able to be connected to an existing device, was designed, constructed, and tested. The performance of the generator as well as the impact of the generator on the operation of the boiler was investigated under various operating conditions. The boiler gained auxiliary power and could become a combined heat and power unit allowing self-sufficient operation. The created unit represents an independent source of electricity with effective use of fuel.

Power generation from thermoelectric system-embedded Plexiglas for green building technology

KAUST Repository

Inayat, Salman Bin

2012-06-09

Thermoelectric materials embedded through or inside exterior glass windows can act as a viable source of supplemental power in geographic locations where hot weather dominates. This thermoelectricity is generated because of the thermal difference between the high temperature outside and the relatively cold temperature inside. Using physical vapor deposition process, we experimentally verify this concept by embedding bismuth telluride and antimony telluride through the 5 mm Plexiglas to demonstrate 10 nW of thermopower generation with a temperature gradient of 21 °C. Albeit tiny at this point with non-optimized design and development, this concept can be extended for relatively large-scale power generation as an additional power supply for green building technology.

Coal-fired Power Plants with Flexible Amine-based CCS and Co-located Wind Power: Environmental, Economic and Reliability Outcomes

Science.gov (United States)

Bandyopadhyay, Rubenka

Carbon Capture and Storage (CCS) technologies provide a means to significantly reduce carbon emissions from the existing fleet of fossil-fired plants, and hence can facilitate a gradual transition from conventional to more sustainable sources of electric power. This is especially relevant for coal plants that have a CO2 emission rate that is roughly two times higher than that of natural gas plants. Of the different kinds of CCS technology available, post-combustion amine based CCS is the best developed and hence more suitable for retrofitting an existing coal plant. The high costs from operating CCS could be reduced by enabling flexible operation through amine storage or allowing partial capture of CO2 during high electricity prices. This flexibility is also found to improve the power plant's ramp capability, enabling it to offset the intermittency of renewable power sources. This thesis proposes a solution to problems associated with two promising technologies for decarbonizing the electric power system: the high costs of the energy penalty of CCS, and the intermittency and non-dispatchability of wind power. It explores the economic and technical feasibility of a hybrid system consisting of a coal plant retrofitted with a post-combustion-amine based CCS system equipped with the option to perform partial capture or amine storage, and a co-located wind farm. A techno-economic assessment of the performance of the hybrid system is carried out both from the perspective of the stakeholders (utility owners, investors, etc.) as well as that of the power system operator. (Abstract shortened by ProQuest.).

An Improved Flexible Solar Thermal Energy Integration Process for Enhancing the Coal-Based Energy Efficiency and NOx Removal Effectiveness in Coal-Fired Power Plants under Different Load Conditions

Directory of Open Access Journals (Sweden)

Yu Han

2017-09-01

Full Text Available An improved flexible solar-aided power generation system (SAPG for enhancing both selective catalytic reduction (SCR de-NOx efficiency and coal-based energy efficiency of coal-fired power plants is proposed. In the proposed concept, the solar energy injection point is changed for different power plant loads, bringing about different benefits for coal-fired power generation. For partial/low load, solar energy is beneficially used to increase the flue gas temperature to guarantee the SCR de-NOx effectiveness as well as increase the boiler energy input by reheating the combustion air. For high power load, solar energy is used for saving steam bleeds from turbines by heating the feed water. A case study for a typical 1000 MW coal-fired power plant using the proposed concept has been performed and the results showed that, the SCR de-NOx efficiency of proposed SAPG could increase by 3.1% and 7.9% under medium load and low load conditions, respectively, as compared with the reference plant. The standard coal consumption rate of the proposed SAPG could decrease by 2.68 g/kWh, 4.05 g/kWh and 6.31 g/kWh for high, medium and low loads, respectively, with 0.040 USD/kWh of solar generated electricity cost. The proposed concept opens up a novel solar energy integration pattern in coal-fired power plants to improve the pollutant removal effectiveness and decrease the coal consumption of the power plant.

Research on a power management system for thermoelectric generators to drive wireless sensors on a spindle unit.

Science.gov (United States)

Li, Sheng; Yao, Xinhua; Fu, Jianzhong

2014-07-16

Thermoelectric energy harvesting is emerging as a promising alternative energy source to drive wireless sensors in mechanical systems. Typically, the waste heat from spindle units in machine tools creates potential for thermoelectric generation. However, the problem of low and fluctuant ambient temperature differences in spindle units limits the application of thermoelectric generation to drive a wireless sensor. This study is devoted to presenting a transformer-based power management system and its associated control strategy to make the wireless sensor work stably at different speeds of the spindle. The charging/discharging time of capacitors is optimized through this energy-harvesting strategy. A rotating spindle platform is set up to test the performance of the power management system at different speeds. The experimental results show that a longer sampling cycle time will increase the stability of the wireless sensor. The experiments also prove that utilizing the optimal time can make the power management system work more effectively compared with other systems using the same sample cycle.

Silicon nanowire networks for multi-stage thermoelectric modules

International Nuclear Information System (INIS)

Norris, Kate J.; Garrett, Matthew P.; Zhang, Junce; Coleman, Elane; Tompa, Gary S.; Kobayashi, Nobuhiko P.

2015-01-01

Highlights: • Fabricated flexible single, double, and quadruple stacked Si thermoelectric modules. • Measured an enhanced power production of 27%, showing vertical stacking is scalable. • Vertically scalable thermoelectric module design of semiconducting nanowires. • Design can utilize either p or n-type semiconductors, both types are not required. • ΔT increases with thickness therefore power/area can increase as modules are stacked. - Abstract: We present the fabrication and characterization of single, double, and quadruple stacked flexible silicon nanowire network based thermoelectric modules. From double to quadruple stacked modules, power production increased 27%, demonstrating that stacking multiple nanowire thermoelectric devices in series is a scalable method to generate power by supplying larger temperature gradient. We present a vertically scalable multi-stage thermoelectric module design using semiconducting nanowires, eliminating the need for both n-type and p-type semiconductors for modules

Thermoelectric automotive waste heat energy recovery using maximum power point tracking

International Nuclear Information System (INIS)

Yu Chuang; Chau, K.T.

2009-01-01

This paper proposes and implements a thermoelectric waste heat energy recovery system for internal combustion engine automobiles, including gasoline vehicles and hybrid electric vehicles. The key is to directly convert the heat energy from automotive waste heat to electrical energy using a thermoelectric generator, which is then regulated by a DC-DC Cuk converter to charge a battery using maximum power point tracking. Hence, the electrical power stored in the battery can be maximized. Both analysis and experimental results demonstrate that the proposed system can work well under different working conditions, and is promising for automotive industry.

Natural radioactivity level in coal and ash collected from Baoji coal-fired power plant

International Nuclear Information System (INIS)

Jia Xiaodan; Lu Xinwei

2006-01-01

Specific activities of natural radionuclides 226 Ra, 232 Th and 40 K were assessed in coal (3 samples), fly ash (17 samples) and bottom ash (6 samples) collected from Baoji coal-fired power plant. This paper analyzed the characteristics of 226 Ra, 232 Th and 40 K contents in bottom ash and fly ash, and studied the concentration factors of these radionuclides in ash in relation to those in coal. The level of natural radionuclides 226 Ra, 232 Th and 40 K of coal collected from Baoji coal-fired power plant are in the range of radionuclides contents of Chinese coal. The natural radioactivity level of fly ash collected from Baoji coal-fired power plant is close to Beijing and Shanghai coal-fired power plants. The paper farther assessed the possibility of fly ash of Baoji coal-fired power plant used as building materials according to the state standard. The results show that there are 29% samples exceeding the state limit when fly ash used as building materials. So the usage of fly ash in building material should be controlled. (authors)

Increasing the thermoelectric power factor of Ge17Sb2Te20 by adjusting the Ge/Sb ratio

Science.gov (United States)

Williams, Jared B.; Mather, Spencer P.; Page, Alexander; Uher, Ctirad; Morelli, Donald T.

2017-07-01

We have investigated the thermoelectric properties of Ge17Sb2Te20. This compound is a known phase change material with electronic properties that depend strongly on temperature. The thermoelectric properties of this compound can be tuned by altering the stoichiometry of Ge and Sb without the use of additional foreign elements during synthesis. This tuning results in a 26% increase in the thermoelectric power factor at 723 K. Based on a single parabolic band model we show that the pristine material is optimally doped, and thus, a reduction in the lattice thermal conductivity of pure Ge17Sb2Te20 should result in an enhanced thermoelectric figure of merit.

Externalities of biomass based electricity production compared to power generation from coal in the Netherlands

International Nuclear Information System (INIS)

Faaij, A.; Meuleman, B.

1997-12-01

Externalities of electricity production from biomass and coal are investigated and compared for the Dutch context. Effects on economic activity and employment are investigated by means of Input/Output and multiplier tables. Valuations of damage from emissions to air are based on generic data from other studies. In addition, external costs are estimated for nitrogen leaching and for the use of agrochemicals for energy crop production. The average private costs for biomass and coal based power generation are projected to be 68 and 38 mECU/kWh respectively in the year 2005. It is assumed that biomass production takes place on fallow land. Coal mining is excluded from the analysis. If the quantified external damages and benefits are included the cost range for bio-electricity is 53-70 mECU/kWh and 45-72 mECU/kWh for coal. Indirect economic effects (increment of Gross Domestic Product) and the difference in CO2 emissions are the most important distinguishing factors between coal and biomass in economic terms. Damage costs of other emissions to air (NOx, SO2, dust and CO) are of the same order of magnitude for both coal and biomass (coal mining excluded). In this analysis environmental impacts of energy farming are compared mainly to fallow land focused on the use of fertilizers and agrochemicals. The related damage costs appear to be low but should be considered as a preliminary estimate only. The quantitative outcomes should not be considered as the external costs of the two fuel cycles studied. Many impacts have not been valued and large uncertainties persist e.g. with respect to the costs of climate change and numerous dose response relations. More detailed analysis is required with respect to macro-economic impacts. The results serve as a first indication, but the outcomes plead for the support of bio-electricity production and/or taxation of coal based power generation. 88 refs

Peak capacity analysis of coal power in China based on full-life cycle cost model optimization

Science.gov (United States)

Yan, Xiaoqing; Zhang, Jinfang; Huang, Xinting

2018-02-01

13th five-year and the next period are critical for the energy and power reform of China. In order to ease the excessive power supply, policies have been introduced by National Energy Board especially toward coal power capacity control. Therefore the rational construction scale and scientific development timing for coal power are of great importance and paid more and more attentions. In this study, the comprehensive influence of coal power reduction policies is analyzed from diverse point of views. Full-life cycle cost model of coal power is established to fully reflect the external and internal cost. Then this model is introduced in an improved power planning optimization theory. The power planning and diverse scenarios production simulation shows that, in order to meet the power, electricity and peak balance of power system, China’s coal power peak capacity is within 1.15 ∼ 1.2 billion kilowatts before or after 2025. The research result is expected to be helpful to the power industry in 14th and 15th five-year periods, promoting the efficiency and safety of power system.

New Technology for Microfabrication and Testing of a Thermoelectric Device for Generating Mobile Electrical Power

Science.gov (United States)

Prasad, Narashimha S.; Taylor, Patrick J.; Trivedi, Sudhir B.; Kutcher, Susan

2010-01-01

We report the results of fabrication and testing of a thermoelectric power generation module. The module was fabricated using a new "flip-chip" module assembly technique that is scalable and modular. This technique results in a low value of contact resistivity ( surfaces. Under mild testing, a power of 22 mW/sq cm was obtained from small (electrical power of practical and usable magnitude for remote applications using thermoelectric power generation technologies.

3D printing of shape-conformable thermoelectric materials using all-inorganic Bi2Te3-based inks

Science.gov (United States)

Kim, Fredrick; Kwon, Beomjin; Eom, Youngho; Lee, Ji Eun; Park, Sangmin; Jo, Seungki; Park, Sung Hoon; Kim, Bong-Seo; Im, Hye Jin; Lee, Min Ho; Min, Tae Sik; Kim, Kyung Tae; Chae, Han Gi; King, William P.; Son, Jae Sung

2018-04-01

Thermoelectric energy conversion offers a unique solution for generating electricity from waste heat. However, despite recent improvements in the efficiency of thermoelectric materials, the widespread application of thermoelectric generators has been hampered by challenges in fabricating thermoelectric materials with appropriate dimensions to perfectly fit heat sources. Herein, we report an extrusion-based three-dimensional printing method to produce thermoelectric materials with geometries suitable for heat sources. All-inorganic viscoelastic inks were synthesized using Sb2Te3 chalcogenidometallate ions as inorganic binders for Bi2Te3-based particles. Three-dimensional printed materials with various geometries showed homogenous thermoelectric properties, and their dimensionless figure-of-merit values of 0.9 (p-type) and 0.6 (n-type) were comparable to the bulk values. Conformal cylindrical thermoelectric generators made of 3D-printed half rings mounted on an alumina pipe were studied both experimentally and computationally. Simulations show that the power output of the conformal, shape-optimized generator is higher than that of conventional planar generators.

A comparative study of health hazards and environmental impacts for electricity generation through nuclear energy hidroelectricity and coal fired thermoeletrical generation

International Nuclear Information System (INIS)

Guimaraes, C.A.

1982-01-01

Environmental impacts and health hazards were comparatively assessed in regard to electricity generation via nuclear energy, hidraulic dams and coal firing. The main aspects covered the nuclear reactor and its associated nuclear fuel cycle, coal fired thermoelectrical power plant its associated coal industry, and hidroelectrical power plant and its dam. Besides specific comparisons of impacts in the air, water, soil and health hazards an evaluation for the Brazilian case was made based on a forecast of electricity demand up to the year 2020. For the nuclear option the consequences were analysed based on American data since no data is yet available for Brazil. Coal firing option was also analised for based heavily on American data due to small Brazilian experience in this sector of energy generation. For hydroelectrical option Brazilian data were used mostly from CESP for comparative purposes. These alternatives for generation of electricity considered in this study are the most relevant for the next four decades for Brazil. (Author) [pt

Climate change impacts on thermoelectric-power generation in the United States

Science.gov (United States)

Liu, L.

2015-12-01

Thermoelectric-power generation accounts for more than 70% of the total electricity generation in the United States, which requires large amounts of water for cooling purposes. Water withdrawals for thermoelectric-power generation accounted for 45% of total water use in the United States in 2010. Across the country, water demand from power plants is increasing due to pressures from growing populations and other needs, and is straining existing water resources. Moreover, temperature exceedance in receiving waters has increasingly caused power plants shut downs across parts of the country. Thermoelectric power is vulnerable to climate change owing to the combined effects of lower summer river flows and higher receiving water temperatures. In addition, the efficiency of production is reduced as air temperature rises, which propagates to more unfulfilled power demand during peak seasons. Therefore, a holistic modeling framework of water-energy-climate for the contiguous U.S. is presented here to quantify thermal output from power plants and estimate water use and energy production fluctuations due to ambient climate as well as environmental regulations. The model is calibrated on a plant-by-plant basis for year 2010 and 2011 using the available power plant inventory from the Energy Information Administration (EIA). Simulations were carried out for years 2012 and 2013, and results show moderate improvements in capturing thermal output variabilities after calibration. Future power plant operations under scenarios featuring different climate and regulatory settings were investigated. Results demonstrate the interplay among water, energy and climate, and that future changes in climate and socioeconomics significantly affect power plant operations, which may provide insights to climate change mitigation considerations and energy decisions.

Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle

Energy Technology Data Exchange (ETDEWEB)

None

2012-01-31

The thermoelectric generator shorting system provides the capability to monitor and short-out individual thermoelectric couples in the event of failure. This makes the series configured thermoelectric generator robust to individual thermoelectric couple failure. Open circuit detection of the thermoelectric couples and the associated short control is a key technique to ensure normal functionality of the TE generator under failure of individual TE couples. This report describes a five-year effort whose goal was the understanding the issues related to the development of a thermoelectric energy recovery device for a Class-8 truck. Likely materials and important issues related to the utility of this generator were identified. Several prototype generators were constructed and demonstrated. The generators developed demonstrated several new concepts including advanced insulation, couple bypass technology and the first implementation of skutterudite thermoelectric material in a generator design. Additional work will be required to bring this system to fruition. However, such generators offer the possibility of converting energy that is otherwise wasted to useful electric power. Uur studies indicate that this can be accomplished in a cost-effective manner for this application.

Beat the Deviations in Estimating Maximum Power of Thermoelectric Modules

DEFF Research Database (Denmark)

Gao, Junling; Chen, Min

2013-01-01

Under a certain temperature difference, the maximum power of a thermoelectric module can be estimated by the open-circuit voltage and the short-circuit current. In practical measurement, there exist two switch modes, either from open to short or from short to open, but the two modes can give...... different estimations on the maximum power. Using TEG-127-2.8-3.5-250 and TEG-127-1.4-1.6-250 as two examples, the difference is about 10%, leading to some deviations with the temperature change. This paper analyzes such differences by means of a nonlinear numerical model of thermoelectricity, and finds out...... that the main cause is the influence of various currents on the produced electromotive potential. A simple and effective calibration method is proposed to minimize the deviations in specifying the maximum power. Experimental results validate the method with improved estimation accuracy....

Application of Thermoelectric Devices to Fuel Cell Power Generation: Demonstration and Evaluation

National Research Council Canada - National Science Library

Huston, John; Wyatt, Chris; Nichols, Chris; Binder, Michael J; Holcomb, Franklin H

2004-01-01

The Department of Defense (DOD) is concerned with reliable and cost-effective power generation of on-site power generators as well as minimizing the environment impact of these generators. Thermoelectric (TE...

Experimental Study on Effect of Operating Conditions on Thermoelectric Power Generation

DEFF Research Database (Denmark)

Mahmoudi Nezhad, Sajjad; Rezaniakolaei, Alireza; Rosendahl, Lasse Aistrup

2017-01-01

Effect of boundary conditions of thermal reservoirs on power generation of thermoelectric modules (TEMs) is examined experimentally. To realize the characteristics of the power generation by the TEMs, the system performance is studied over various volumetric flow rates and flow temperatures...

Coal gasification and the power production market

International Nuclear Information System (INIS)

Howington, K.; Flandermeyer, G.

1995-01-01

The US electric power production market is experiencing significant changes sparking interest in the current and future alternatives for power production. Coal gasification technology is being marketed to satisfy the needs of the volatile power production industry. Coal gasification is a promising power production process in which solid coal is burned to produce a synthesis gas (syn gas). The syn gas may be used to fuel combustion integrated into a facility producing electric power. Advantages of this technology include efficient power production, low flue gas emissions, flexible fuel utilization, broad capability for facility integration, useful process byproducts, and decreased waste disposal. The primary disadvantages are relatively high capital costs and lack of proven long-term operating experience. Developers of coal gasification intend to improve on these disadvantages and lop a strong position in the power generation market. This paper is a marketing analysis of the partial oxidation coal gasification processes emerging in the US in response to the market factors of the power production industry. A brief history of these processes is presented, including the results of recent projects exploring the feasibility of integrated gasification combined cycle (IGCC) as a power production alternative. The current power generation market factors are discussed, and the status of current projects is presented including projected performance

Life Cycle Assessment of Coal-fired Power Production

Energy Technology Data Exchange (ETDEWEB)

Spath, P. L.; Mann, M. K.; Kerr, D. R.

1999-09-01

Coal has the largest share of utility power generation in the US, accounting for approximately 56% of all utility-produced electricity (US DOE, 1998). Therefore, understanding the environmental implications of producing electricity from coal is an important component of any plan to reduce total emissions and resource consumption. A life cycle assessment (LCA) on the production of electricity from coal was performed in order to examine the environmental aspects of current and future pulverized coal boiler systems. Three systems were examined: (1) a plant that represents the average emissions and efficiency of currently operating coal-fired power plants in the US (this tells us about the status quo), (2) a new coal-fired power plant that meets the New Source Performance Standards (NSPS), and (3) a highly advanced coal-fired power plant utilizing a low emission boiler system (LEBS).

Utilization of municipal wastewater for cooling in thermoelectric power plants: Evaluation of the combined cost of makeup water treatment and increased condenser fouling

Energy Technology Data Exchange (ETDEWEB)

Walker, Michael E. [Illinois Inst. of Technology, Chicago, IL (United States). Dept. of Chemical and Biological Engineering; Theregowda, Ranjani B. [Carnegie Mellon Univ., Pittsburgh, PA (United States). Dept of Civil and Mechanical Engineering; Safari, Iman [Illinois Inst. of Technology, Chicago, IL (United States). Dept. of Chemical and Biological Engineering; Abbasian, Javad [Illinois Inst. of Technology, Chicago, IL (United States). Dept. of Chemical and Biological Engineering; Arastoopour, Hamid [Illinois Inst. of Technology, Chicago, IL (United States). Dept. of Chemical and Biological Engineering; Dzombak, David A. [Carnegie Mellon Univ., Pittsburgh, PA (United States). Dept of Civil and Mechanical Engineering; Hsieh, Ming-Kai [Tamkang Univ., Taipei (Taiwan). Waer Resources Management and Policy Research Center; Miller, David C. [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

2013-10-01

A methodology is presented to calculate the total combined cost (TCC) of water sourcing, water treatment and condenser fouling in the recirculating cooling systems of thermoelectric power plants. The methodology is employed to evaluate the economic viability of using treated municipal wastewater (MWW) to replace the use of freshwater as makeup water to power plant cooling systems. Cost analyses are presented for a reference power plant and five different tertiary treatment scenarios to reduce the scaling tendencies of MWW. Results indicate that a 550 MW sub-critical coal fired power plant with a makeup water requirement of 29.3 ML/day has a TCC of $3.0 - 3.2 million/yr associated with the use of treated MWW for cooling. (All costs USD 2009). This translates to a freshwater conservation cost of $0.29/kL, which is considerably lower than that of dry air cooling technology, $1.5/kL, as well as the 2020 conservation cost target set by the U.S. Department of Energy, $0.74/kL. Results also show that if the available price of freshwater exceeds that of secondary-treated MWW by more than $0.13-0.14/kL, it can be economically advantageous to purchase secondary MWW and treat it for utilization in the recirculating cooling system of a thermoelectric power plant.

Design and analysis of solar thermoelectric power generation system

Science.gov (United States)

Vatcharasathien, Narong; Hirunlabh, Jongjit; Khedari, Joseph; Daguenet, Michel

2005-09-01

This article reports on the design and performance analysis of a solar thermoelectric power generation plant (STEPG). The system considers both truncated compound parabolic collectors (CPCs) with a flat receiver and conventional flat-plate collectors, thermoelectric (TE) cooling and power generator modules and appropriate connecting pipes and control devices. The design tool uses TRNSYS IIsibat-15 program with a new component we developed for the TE modules. The main input data of the system are the specifications of TE module, the maximum hot side temperature of TE modules, and the desired power output. Examples of the design using truncated CPC and flat-plate collectors are reported and discussed for various slope angle and half-acceptance angle of CPC. To minimize system cost, seasonal adjustment of the slope angle between 0° and 30° was considered, which could give relatively high power output under Bangkok ambient condition. Two small-scale STEPGs were built. One of them uses electrical heater, whereas the other used a CPC with locally made aluminum foil reflector. Measured data showed reasonable agreement with the model outputs. TE cooling modules were found to be more appropriate. Therefore, the TRNSYS software and the developed TE component offer an extremely powerful tool for the design and performance analysis of STEPG plant.

A Hybrid Maximum Power Point Tracking Method for Automobile Exhaust Thermoelectric Generator

Science.gov (United States)

Quan, Rui; Zhou, Wei; Yang, Guangyou; Quan, Shuhai

2017-05-01

To make full use of the maximum output power of automobile exhaust thermoelectric generator (AETEG) based on Bi2Te3 thermoelectric modules (TEMs), taking into account the advantages and disadvantages of existing maximum power point tracking methods, and according to the output characteristics of TEMs, a hybrid maximum power point tracking method combining perturb and observe (P&O) algorithm, quadratic interpolation and constant voltage tracking method was put forward in this paper. Firstly, it searched the maximum power point with P&O algorithms and a quadratic interpolation method, then, it forced the AETEG to work at its maximum power point with constant voltage tracking. A synchronous buck converter and controller were implemented in the electric bus of the AETEG applied in a military sports utility vehicle, and the whole system was modeled and simulated with a MATLAB/Simulink environment. Simulation results demonstrate that the maximum output power of the AETEG based on the proposed hybrid method is increased by about 3.0% and 3.7% compared with that using only the P&O algorithm and the quadratic interpolation method, respectively. The shorter tracking time is only 1.4 s, which is reduced by half compared with that of the P&O algorithm and quadratic interpolation method, respectively. The experimental results demonstrate that the tracked maximum power is approximately equal to the real value using the proposed hybrid method,and it can preferentially deal with the voltage fluctuation of the AETEG with only P&O algorithm, and resolve the issue that its working point can barely be adjusted only with constant voltage tracking when the operation conditions change.

Bulk Material Based Thermoelectric Energy Harvesting for Wireless Sensor Applications

International Nuclear Information System (INIS)

Wang, W S; Magnin, W; Wang, N; Hayes, M; O'Flynn, B; O'Mathuna, C

2011-01-01

The trend towards smart building and modern manufacturing demands ubiquitous sensing in the foreseeable future. Self-powered Wireless sensor networks (WSNs) are essential for such applications. This paper describes bulk material based thermoelectric generator (TEG) design and implementation for WSN. A 20cm 2 Bi 0.5 Sb 1.5 Te 3 based TEG was created with optimized configuration and generates 2.7mW in typical condition. A novel load matching method is used to maximize the power output. The implemented power management module delivers 651μW to WSN in 50 deg. C. With average power consumption of Tyndall WSN measured at 72μW, feasibility of utilizing bulk material TEG to power WSN is demonstrated.

Nanocluster metal films as thermoelectric material for radioisotope mini battery unit

International Nuclear Information System (INIS)

Borisyuk, P.V.; Krasavin, A.V.; Tkalya, E.V.; Lebedinskii, Yu.Yu.; Vasiliev, O.S.; Yakovlev, V.P.; Kozlova, T.I.; Fetisov, V.V.

2016-01-01

The paper is devoted to studying the thermoelectric and structural properties of films based on metal nanoclusters (Au, Pd, Pt). The experimental results of the study of single nanoclusters’ tunneling conductance obtained with scanning tunneling spectroscopy are presented. The obtained data allowed us to evaluate the thermoelectric power of thin film consisting of densely packed individual nanoclusters. It is shown that such thin films can operate as highly efficient thermoelectric materials. A scheme of miniature thermoelectric radioisotope power source based on the thorium-228 isotope is proposed. The efficiency of the radioisotope battery using thermoelectric converters based on nanocluster metal films is shown to reach values up to 1.3%. The estimated characteristics of the device are comparable with the parameters of up-to-date radioisotope batteries based on nickel-63.

Low flows and water temperature risks to Asian coal power plants in a warming world

Science.gov (United States)

Wang, Y.; Byers, E.; Parkinson, S.; Wanders, N.; Wada, Y.; Bielicki, J. M.

2017-12-01

Thermoelectric power generation requires cooling, normally provided by wet cooling systems. The withdrawal and discharge of cooling water are subject to regulation. Therefore, operation of power plants may be vulnerable to changes in streamflow and rises in water temperatures. In Asia, about 489 GW of coal-fired power plants are currently under construction, permitted, or announced. Using a comprehensive dataset of these planned coal power plants (PCPPs) and cooling water use models, we investigated whether electricity generation at these power plants will be limited by streamflow and water temperature. Daily streamflow and water temperature time series are from the high-resolution (0.08ox0.08o) runs of the PCRGLOBWB hydrological model, driven by downscaled meteorological forcing from five global climate models. We compared three climate change scenarios (1.5oC, 2oC, and 3oC warming in global mean temperature) and three cooling system choice scenarios (freshwater once-through, freshwater cooling tower, and "business-as-usual" - where a PCPP uses the same cooling system as the nearest existing coal power plant). The potential available capacity of the PCPPs increase slightly from the 1.5oC to the 2oC and 3oC warming scenario due to increase in streamflow. The once-through cooling scenario results in virtually zero available capacity at the PCPPs. The other two cooling scenarios result in about 20% of the planned capacity being unavailable under all warming scenarios. Hotspots of the most water-limited PCPPs are in Pakistan, northwestern India, northwestern and north-central China, and northern Vietnam, where most of the PCPPs will face 30% to 90% unavailable nameplate capacity on annual average. Since coal power plants cannot operate effectively when the capacity factor falls below a minimum load level (about 20% to 50%), the actual limitation on generation capacity would be larger. In general, the PCPPs that will have the highest limitation on annual average

Balance of natural radionuclides in the brown coal based power generation and harmlessness of the residues and side product utilization

International Nuclear Information System (INIS)

Schulz, Hartmut; Kunze, Christian; Hummrich, Holger

2017-01-01

During brown coal combustion a partial enrichment of natural radionuclides occurs in different residues. Residues and side product from brown coal based power generation are used in different ways, for example filter ashes and gypsum from flue gas desulfurization facilities are used in the construction materials fabrication and slags for road construction. Detailed measurement and accounting of radionuclides in the mass throughputs in coal combustion power plants have shown that the utilized gypsum and filter ashes are harmless in radiologic aspects.

Thermoelectric power in n-InSe

International Nuclear Information System (INIS)

Casanovas, A.; Cantarero, A.; Segura, A.

1985-01-01

Thermoelectric power of InSe samples doped with tin has been measured as functions of the doping concentration in the range of 0.01 to 10% Sn and of the temperature in the range of 50 to 550 K. In the low temperature range the results obtained are coherent with the two-dimensional behaviour of electrons proposed by other authors. About 100 K the results can be explained successfully by introducing the same scattering mechanisms used to interpret the temperature dependence of the electron mobility

Improving the Efficiency of a Nucler Power Plant Using a Thermoelectric Cogeneration System

Directory of Open Access Journals (Sweden)

Rauf Terzi

2018-02-01

Full Text Available The efficiencies of nuclear power plants are rather poor having the ratio %30 by using the conventional energy/exergy tools. According to that information, large amount of energy is wasted during condensation and thrown out to the environment. Thermoelectric generator (TEG system has a potential to be used as a heat exchanging technology to produce power with a relatively low efficiency (about 5% and it can transform the temperature difference into electricity and generate clean electrical energy. In the present study, we offer a novel system to recover the waste heat from a VVER-1000 nuclear power plant. The heat transfer of the TEG is analyzed numerically with respect to the various temperature ranges and constant mass flow rate of the exhaust steam entering the system. In the analyses, different hot temperature ranges (35ºC, 45ºC and 55ºC and a constant cold temperature (i.e. 18ºC are used for a HZ-20 thermoelectric module and it has been proven that the designed TEG can produce the maximum output power of 76,956 MW for a temperature difference ∆T=37 and the conversion efficiency of 3,854% sits. The TEG is designed for the condenser of a 1000 MW nuclear power plant. It's shown that about 2,0% increasing in the power plant efficiency is expected by using the selected thermoelectric generator in the condensation cycle. Article History: Received: July 15th 2017; Received:  October 17th 2017; Accepted: February 13rd 2018; Available online How to Cite This Article: Terzi, R. and Kurt, E. (2018, Improving the efficiency of a nuclear power plant using a thermoelectric cogeneration system, Int. Journal of Renewable Energy Development, 7(1, 77-84. https://doi.org/10.14710/ijred.7.1.77-84

High thermoelectric power factor from multilayer solution-processed organic films

Science.gov (United States)

Zuo, Guangzheng; Andersson, Olof; Abdalla, Hassan; Kemerink, Martijn

2018-02-01

We investigate the suitability of the "sequential doping" method of organic semiconductors for thermoelectric applications. The method consists of depositing a dopant (F4TCNQ) containing solution on a previously cast semiconductor (P3HT) thin film to achieve high conductivity, while preserving the morphology. For very thin films (˜25 nm), we achieve a high power factor around 8 μW/mK-2 with a conductivity over 500 S/m. For the increasing film thickness, conductivity and power factor show a decreasing trend, which we attribute to the inability to dope the deeper parts of the film. Since thick films are required to extract significant power from thermoelectric generators, we developed a simple additive technique that allows the deposition of an arbitrary number of layers without significant loss in conductivity or power factor that, for 5 subsequent layers, remain at ˜300 S/m and ˜5 μW/mK-2, respectively, whereas the power output increases almost one order of magnitude as compared to a single layer. The efficient doping in multilayers is further confirmed by an increased intensity of (bi)polaronic features in the UV-Vis spectra.

Clean Power Generation from the Intractable Natural Coalfield Fires: Turn Harm into Benefit.

Science.gov (United States)

Shi, Bobo; Su, Hetao; Li, Jinshi; Qi, Haining; Zhou, Fubao; Torero, José L; Chen, Zhongwei

2017-07-13

The coal fires, a global catastrophe for hundreds of years, have been proved extremely difficult to control, and hit almost every coal-bearing area globally. Meanwhile, underground coal fires contain tremendous reservoir of geothermal energy. Approximately one billion tons of coal burns underground annually in the world, which could generate ~1000 GW per annum. A game-changing approach, environmentally sound thermal energy extraction from the intractable natural coalfield fires, is being developed by utilizing the waste energy and reducing the temperature of coalfield fires at the same time. Based on the Seebeck effect of thermoelectric materials, the temperature difference between the heat medium and cooling medium was employed to directly convert thermal energy into clean electrical energy. By the time of December 2016, the power generation from a single borehole at Daquan Lake fire district in Xinjiang has been exceeded 174.6 W. The field trial demonstrates that it is possible to exploit and utilize the waste heat resources in the treated coal fire areas. It promises a significant impact on the structure of global energy generation and can also promote progress in thermoelectric conversion materials, geothermal exploration, underground coal fires control and other energy related areas.

Thermoelectric performance of spin Seebeck effect in Fe3O4/Pt-based thin film heterostructures

Directory of Open Access Journals (Sweden)

R. Ramos

2016-10-01

Full Text Available We report a systematic study on the thermoelectric performance of spin Seebeck devices based on Fe3O4/Pt junction systems. We explore two types of device geometries: a spin Hall thermopile and spin Seebeck multilayer structures. The spin Hall thermopile increases the sensitivity of the spin Seebeck effect, while the increase in the sample internal resistance has a detrimental effect on the output power. We found that the spin Seebeck multilayers can overcome this limitation since the multilayers exhibit the enhancement of the thermoelectric voltage and the reduction of the internal resistance simultaneously, therefore resulting in significant power enhancement. This result demonstrates that the multilayer structures are useful for improving the thermoelectric performance of the spin Seebeck effect.

Radiological impact assessment of coal and nuclear base power plants in India

International Nuclear Information System (INIS)

Ramachandran, T.V.

2007-01-01

Environmental problems concerned with the use of coal as a fuel in thermal power plants (TPS) is due to the production of fly ash. Coal contains tracers of primordial radionuclide and its burning is one of the sources of technologically enhanced exposure from natural radionuclides. When it is burnt in TPSs, the fly ash, emitted through the stack is enriched in radionuclide and so combustion of coal on a large scale for thermal power generation assumes importance. Many of these TPSs are located in thickly populated areas. Radioactivity content of the coal from the coalfields of eastern parts of the country is found to be higher than that of other coalfields. In India coal combustion accounts nearly 73% of the total installed capacity for power generation. A sample study was carried out by this center on coal and fly ash samples collected from more than 35 TPS spread all over the country with a total installed capacity of 10000 MW(e), for their-radioactivity content. Radiation doses to the population residing within 90 km radius of each TPS have been computed. Besides another set of 15 TPSs were studied for thermal pollution emission and trace element concentration. Operation of these TPSs has resulted in effective dose commitments from doses to bones, lungs and thyroid of 200 man-Sv.y -1 and from doses to the whole body, of 70 man-Sv.y -1 . Dose commitments to the population living within 90 km radius of the TPSs and NPPs in India have been computed and have been compared. Attempt is made to assess the inhalation dose from the radioactivity released from a typical 500 MW(e) TPS and its impact related to chemical pollutants. Impact in terms of Environmental Quality Index (EQI) due to conventional pollutions have been computed and compared with those due to the nuclear power plants (NPPs). Paper gives the summary of the study. (author)

Electrical properties and figures of merit for new chalcogenide-based thermoelectric materials

Energy Technology Data Exchange (ETDEWEB)

Schindler, J L; Hogan, T P; Brazis, P W; Kannewurf, C R; Chung, D Y; Kanatzidis, M G

1997-07-01

New Bi-based chalcogenide compounds have been prepared using the polychalcogenide flux technique for crystal growth. These materials exhibit characteristics of good thermoelectric materials. Single crystals of the compound CsBi{sub 4}Te{sub 6} have shown conductivity as high as 2440 S/cm with a p-type thermoelectric power of {approx}+110 {micro}V/K at room temperature. A second compound, {beta}-K{sub 2}Bi{sub 8}Se{sub 13} shows lower conductivity {approx}240 S/cm, but a larger n-type thermopower {approx}{minus}200 {micro}V/K. Thermal transport measurements have been performed on hot-pressed pellets of these materials and the results show comparable or lower thermal conductivities than Bi{sub 2}Te{sub 3}. This improvement may reflect the reduced lattice symmetry of the new chalcogenide thermoelectrics. The thermoelectric figure of merit for CsBi{sub 4}Te{sub 6} reaches ZT {approx} 0.32 at 260 K and for {beta}-K{sub 2}Bi{sub 8}Se{sub 13} ZT {approx} 0.32 at room temperature, indicating that these compounds are viable candidates for thermoelectric refrigeration applications.

The system of thermoelectric air conditioning based on permeable thermoelements

Directory of Open Access Journals (Sweden)

Cherkez R. G.

2009-04-01

Full Text Available There is thermoelectric air conditioner unit on the basis of permeable cooling thermoelements presented. In thermoelectric air conditioner unit the thermoelectric effects and the Joule–Thomson effect have been used for the air stream cooling. There have been described the method of temperature distribution analysis, the determinations of energy conversion power characteristics and design style of permeable thermoelement with maximum coefficient of performance described. The results of computer analysis concerning the application of the thermoelement legs material on the basis of Bi2Te3 have shown the possibility of coefficient of performance increase by a factor of 1,6—1,7 as compared with conventional thermoelectric systems.

Design and Fabrication of Multifunctional Portable Bi2Te3-Based Thermoelectric Camping Lamp

Science.gov (United States)

Zhou, Yi; Li, Gongping

2018-05-01

Camping lamps have been widely used in the lighting, power supply, and intelligent electronic equipment fields. However, applications of traditional chemical and solar camping lamps are largely limited by the physical size of the source and operating conditions. A new prototype multifunctional portable Bi2Te3-based thermoelectric camping lamp (TECL) has been designed and fabricated. Ten parallel light-emitting diodes were lit directly by a Bi2Te3-based thermoelectric generator (TEG). The highest short-circuit current of 0.38 A and open-circuit voltage of 4.2 V were obtained at temperature difference of 115 K. This TECL is attractive for use in multifunctional and extreme applications as it integrates a portable heat source, high-performance TEG, and power management unit.

Gas and coal competition in the EU Power Sector

International Nuclear Information System (INIS)

Cornot-Gandolphe, Sylvie

2014-06-01

Despite its many assets, a confluence of factors - including flat electricity demand, rising use of renewable energy sources, falling wholesale electricity market prices, high gas prices relative to coal and low CO 2 prices - has eroded the competitiveness of natural gas in the EU power sector. The share of natural gas in the EU electricity mix has decreased from 23% in 2010 to 20.5% in 2012. By contrast, coal-fired power stations have been operating at high loads, increasing coal demand by the sector. This thorough analysis by CEDIGAZ of gas, coal and CO 2 dynamics in the context of rising renewables is indispensable to understand what is at stake in the EU power sector and how it will affect future European gas demand. Main findings of the report: - Coal is likely to retain its cost advantage into the coming decade: The relationship between coal, gas and CO 2 prices is a key determinant of the competition between gas and coal in the power sector and will remain the main driver of fuel switching. A supply glut on the international coal market (partly because of an inflow of US coal displaced by shale gas) has led to a sharp decline in coal prices while gas prices, still linked to oil prices to a significant degree, have increased by 42% since 2010. At the same time, CO 2 prices have collapsed, reinforcing coal competitiveness. Our analysis of future trends in coal, gas and CO 2 prices suggests that coal competitive advantage may well persist into the coming decade. - But coal renaissance may still be short-lived: Regulations on emissions of local pollutants, i.e. the Large Plant Combustion Directive (LCPD) and the Industrial Emissions Directive (IED) that will succeed it in 2016, will lead to the retirement of old, inefficient coal-fired power plants. Moreover, the rapid development of renewables, which so far had only impacted gas-fired power plants is starting to take its toll on hard coal plants' profitability. This trend is reinforced by regulation at EU or

Solution synthesis of telluride-based nano-barbell structures coated with PEDOT:PSS for spray-printed thermoelectric generators

Science.gov (United States)

Bae, Eun Jin; Kang, Young Hun; Jang, Kwang-Suk; Lee, Changjin; Cho, Song Yun

2016-05-01

Solution-processable telluride-based heterostructures coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Te-Bi2Te3/PEDOT:PSS) were synthesized through a solution-phase reaction at low temperatures. The water-based synthesis yielded PEDOT:PSS-coated Te-Bi2Te3 nano-barbell structures with a high Seebeck coefficient that can be stably dispersed in water. These hybrid solutions were deposited onto a substrate by the spray-printing method to prepare thermoelectric generators. The thermoelectric properties of the Te-Bi2Te3/PEDOT:PSS hybrid films were significantly enhanced by a simple acid treatment due to the increased electrical conductivity, and the power factor of those materials can be effectively tuned over a wide range depending on the acid concentration of the treatment. The power factors of the synthesized Te-Bi2Te3/PEDOT:PSS hybrids were optimized to 60.05 μW m-1 K-2 with a Seebeck coefficient of 93.63 μV K-1 and an electrical conductivity of 69.99 S cm-1. The flexible thermoelectric generator fabricated by spray-printing Te-Bi2Te3/PEDOT:PSS hybrid solutions showed an open-circuit voltage of 1.54 mV with six legs at ΔT = 10 °C. This approach presents the potential for realizing printing-processable hybrid thermoelectric materials for application in flexible thermoelectric generators.Solution-processable telluride-based heterostructures coated with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Te-Bi2Te3/PEDOT:PSS) were synthesized through a solution-phase reaction at low temperatures. The water-based synthesis yielded PEDOT:PSS-coated Te-Bi2Te3 nano-barbell structures with a high Seebeck coefficient that can be stably dispersed in water. These hybrid solutions were deposited onto a substrate by the spray-printing method to prepare thermoelectric generators. The thermoelectric properties of the Te-Bi2Te3/PEDOT:PSS hybrid films were significantly enhanced by a simple acid treatment due to the increased electrical conductivity, and

Study of a thermoelectric system equipped with a maximum power point tracker for stand-alone electric generation.

Science.gov (United States)

Favarel, C.; Champier, D.; Bédécarrats, J. P.; Kousksou, T.; Strub, F.

2012-06-01

According to the International Energy Agency, 1.4 billion people are without electricity in the poorest countries and 2.5 billion people rely on biomass to meet their energy needs for cooking in developing countries. The use of cooking stoves equipped with small thermoelectric generator to provide electricity for basic needs (LED, cell phone and radio charging device) is probably a solution for houses far from the power grid. The cost of connecting every house with a landline is a lot higher than dropping thermoelectric generator in each house. Thermoelectric generators have very low efficiency but for isolated houses, they might become really competitive. Our laboratory works in collaboration with plane`te-bois (a non governmental organization) which has developed energy-efficient multifunction (cooking and hot water) stoves based on traditional stoves designs. A prototype of a thermoelectric generator (Bismuth Telluride) has been designed to convert a small part of the energy heating the sanitary water into electricity. This generator can produce up to 10 watts on an adapted load. Storing this energy in a battery is necessary as the cooking stove only works a few hours each day. As the working point of the stove varies a lot during the use it is also necessary to regulate the electrical power. An electric DC DC converter has been developed with a maximum power point tracker (MPPT) in order to have a good efficiency of the electronic part of the thermoelectric generator. The theoretical efficiency of the MMPT converter is discussed. First results obtained with a hot gas generator simulating the exhaust of the combustion chamber of a cooking stove are presented in the paper.

CPICOR{trademark}: Clean power from integrated coal-ore reduction

Energy Technology Data Exchange (ETDEWEB)

Wintrell, R.; Miller, R.N.; Harbison, E.J.; LeFevre, M.O.; England, K.S.

1997-12-31

The US steel industry, in order to maintain its basic iron production, is thus moving to lower coke requirements and to the cokeless or direct production of iron. The US Department of Energy (DOE), in its Clean Coal Technology programs, has encouraged the move to new coal-based technology. The steel industry, in its search for alternative direct iron processes, has been limited to a single process, COREX{reg_sign}. The COREX{reg_sign} process, though offering commercial and environmental acceptance, produces a copious volume of offgas which must be effectively utilized to ensure an economical process. This volume, which normally exceeds the internal needs of a single steel company, offers a highly acceptable fuel for power generation. The utility companies seeking to offset future natural gas cost increases are interested in this clean fuel. The COREX{reg_sign} smelting process, when integrated with a combined cycle power generation facility (CCPG) and a cryogenic air separation unit (ASU), is an outstanding example of a new generation of environmentally compatible and highly energy efficient Clean Coal Technologies. This combination of highly integrated electric power and hot metal coproduction, has been designated CPICOR{trademark}, Clean Power from Integrated Coal/Ore Reduction.

Cost structure of coal- and nuclear-fired electric power plants

International Nuclear Information System (INIS)

Helmuth, J.A.

1981-01-01

This dissertation investigates the cost structure of coal and nuclear electric power generation. The emphasis of the paper is to empirically estimate the direct costs of generating base-load electric power at the plant level. Empirically, the paper first investigates the relative comparative costs of nuclear and coal power generation, based on historical operating data. Consideration of the learning curve and other dynamic elements is incorporated in the analysis. The second empirical thrust is to inestigate economies of scale for both technologies. The results from the empirical studies give an indication as to the future and present cost viability of each technology. Implications toward energy policy are discussed

Prospects for advanced coal-fuelled fuel cell power plants

International Nuclear Information System (INIS)

Jansen, D.; Laag, P.C. van der; Oudhuis, A.B.J.; Ribberink, J.S.

1994-01-01

As part of ECN's in-house R and D programmes on clean energy conversion systems with high efficiencies and low emissions, system assessment studies have been carried out on coal gasification power plants integrated with high-temperature fuel cells (IGFC). The studies also included the potential to reduce CO 2 emissions, and to find possible ways for CO 2 extraction and sequestration. The development of this new type of clean coal technology for large-scale power generation is still far off. A significant market share is not envisaged before the year 2015. To assess the future market potential of coal-fuelled fuel cell power plants, the promise of this fuel cell technology was assessed against the performance and the development of current state-of-the-art large-scale power generation systems, namely the pulverized coal-fired power plants and the integrated coal gasification combined cycle (IGCC) power plants. With the anticipated progress in gas turbine and gas clean-up technology, coal-fuelled fuel cell power plants will have to face severe competition from advanced IGCC power plants, despite their higher efficiency. (orig.)

Development of low grade waste heat thermoelectric power generator

Directory of Open Access Journals (Sweden)

Suvit Punnachaiya

2010-07-01

Full Text Available This research aimed to develop a 50 watt thermoelectric power generator using low grade waste heat as a heat source,in order to recover and utilize the excess heat in cooling systems of industrial processes and high activity radioisotope sources. Electricity generation was based on the reverse operation of a thermoelectric cooling (TEC device. The TEC devices weremodified and assembled into a set of thermal cell modules operating at a temperature less than 100°C. The developed powergenerator consisted of 4 modules, each generating 15 watts. Two cascade modules were connected in parallel. Each modulecomprised of 96 TEC devices, which were connected in series. The hot side of each module was mounted on an aluminumheat transfer pipe with dimensions 12.212.250 cm. Heat sinks were installed on the cold side with cooling fans to provideforced air cooling.To test electricity generation in the experiment, water steam was used as a heat source instead of low grade waste heat.The open-circuit direct current (DC of 250 V and the short-circuit current of 1.2 A was achieved with the following operatingconditions: a hot side temperature of 96°C and a temperature difference between the hot and cold sides of 25°C. The DC poweroutput was inverted to an AC power source of 220 V with 50 Hz frequency, which can continuously supply more than 50 wattsof power to a resistive load as long as the heat source was applied to the system. The system achieved an electrical conversionefficiency of about 0.47 percent with the capital cost of 70 US$/W.

Evaluation of power conditioning architectures for energy production enhancement in thermoelectric generator systems

DEFF Research Database (Denmark)

Wu, Hongfei; Sun, Kai; Chen, Min

2014-01-01

A large-scale thermoelectric generator (TEG) system has an unbalanced temperature distribution among the TEG modules, which leads to power mismatch among the modules and decreases the power output of the TEG system. To maximize the power output and minimize the power conversion loss, a centralize...

Paper-Based Origami Flexible and Foldable Thermoelectric Nanogenerator

KAUST Repository

Rojas, Jhonathan Prieto; Conchouso Gonzalez, David; Carreno, Armando Arpys Arevalo; Singh, Devendra; Foulds, Ian G.; Hussain, Muhammad Mustafa

2016-01-01

Paper has been an essential material in our daily life since ancient times. Its affordability, accessibility, adaptability, workability and its easiness of usage makes it an attractive structural material to develop many kind of technologies such as flexible electronics, energy storage and harvesting devices. Additionally, the scientific community has increased its interest on waste heat as an environmentally friendly energy source to support the increasing energy demand. Therefore, in this paper we described two affordable and flexible thermoelectric nanogenerators (TEGs) developed on paper substrates by the usage of simple micromachining and microfabrication techniques. Moreover, they exhibit mechanical stability and adaptability (through folding and cutting techniques) for a diverse set of scenarios where vertical or horizontal schemes can be conveniently used depending on the final application. The first TEG device, implemented on standard paper, generated a power of 0.5 nW (ΔT = 50 K). By changing the substrate to a tearless and extra-smooth polyester paper, the TEG performance was optimized achieving less internal resistance and a greater power of ~80 nW (ΔT = 75 K), at the cost of more rigidity in the substrate. This power represented over three times higher power production than the standard paper–based TEG with same dimensions, number of thermoelectric pairs and temperature difference. Another interesting aspect of paper based TEG is due to its foldability, one can control the temperature difference by unfolding (larger separation between hot and cold ends) and folding (smaller separation). Finally, one of the underlying objectives of this work is to spread the availability of essential technologies to the broad population by inclusion of everyday materials and simple processes.

Paper-Based Origami Flexible and Foldable Thermoelectric Nanogenerator

KAUST Repository

Rojas, Jhonathan Prieto

2016-11-12

Paper has been an essential material in our daily life since ancient times. Its affordability, accessibility, adaptability, workability and its easiness of usage makes it an attractive structural material to develop many kind of technologies such as flexible electronics, energy storage and harvesting devices. Additionally, the scientific community has increased its interest on waste heat as an environmentally friendly energy source to support the increasing energy demand. Therefore, in this paper we described two affordable and flexible thermoelectric nanogenerators (TEGs) developed on paper substrates by the usage of simple micromachining and microfabrication techniques. Moreover, they exhibit mechanical stability and adaptability (through folding and cutting techniques) for a diverse set of scenarios where vertical or horizontal schemes can be conveniently used depending on the final application. The first TEG device, implemented on standard paper, generated a power of 0.5 nW (ΔT = 50 K). By changing the substrate to a tearless and extra-smooth polyester paper, the TEG performance was optimized achieving less internal resistance and a greater power of ~80 nW (ΔT = 75 K), at the cost of more rigidity in the substrate. This power represented over three times higher power production than the standard paper–based TEG with same dimensions, number of thermoelectric pairs and temperature difference. Another interesting aspect of paper based TEG is due to its foldability, one can control the temperature difference by unfolding (larger separation between hot and cold ends) and folding (smaller separation). Finally, one of the underlying objectives of this work is to spread the availability of essential technologies to the broad population by inclusion of everyday materials and simple processes.

Life cycle assessment of coal-fired power plants and sensitivity analysis of CO2 emissions from power generation side

Science.gov (United States)

Yin, Libao; Liao, Yanfen; Zhou, Lianjie; Wang, Zhao; Ma, Xiaoqian

2017-05-01

The life cycle assessment and environmental impacts of a 1000MW coal-fired power plant were carried out in this paper. The results showed that the operation energy consumption and pollutant emission of the power plant are the highest in all sub-process, which accounts for 93.93% of the total energy consumption and 92.20% of the total emission. Compared to other pollutant emissions from the coal-fired power plant, CO2 reached up to 99.28%. Therefore, the control of CO2 emission from the coal-fired power plants was very important. Based on the BP neural network, the amount of CO2 emission from the generation side of coal-fired power plants was calculated via carbon balance method. The results showed that unit capacity, coal quality and unit operation load had great influence on the CO2 emission from coal-fired power plants in Guangdong Province. The use of high volatile and high heat value of coal also can reduce the CO2 emissions. What’s more, under higher operation load condition, the CO2 emissions of 1 kWh electric energy was less.

Microstructures and thermoelectric properties of GeSbTe based layered compounds

Energy Technology Data Exchange (ETDEWEB)

Yan, F.; Zhu, T.J.; Zhao, X.B. [Zhejiang University, State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Hangzhou (China); Dong, S.R. [Zhejiang University, Department of Information and Electronics Engineering, Hangzhou (China)

2007-08-15

Microstructures and thermoelectric properties of Ge{sub 1}Sb{sub 2}Te{sub 4} and Ge{sub 2}Sb{sub 2}Te{sub 5} chalcogenide semiconductors have been investigated to explore the possibility of their thermoelectric applications. The phase transformation from the face-centered cubic to hexagonal structure was observed in Ge{sub 2}Sb{sub 2}Te{sub 5} compounds prepared by the melt spinning technique. The Seebeck coefficient and electrical resistivity of the alloys were increased due to the enhanced scattering of charge carriers at grain boundaries. The maximum power factors of the rapidly solidified Ge{sub 1}Sb{sub 2}Te{sub 4} and Ge{sub 2}Sb{sub 2}Te{sub 5} attained 0.975 x 10{sup -3} Wm{sup -1}K{sup -2} at 750 K and 0.767 x 10{sup -3} Wm{sup -1}K{sup -2} at 643 K respectively, higher than those of water quenched counterparts, implying that thermoelectric properties of GeSbTe based layered compounds can be improved by grain refinement. The present results show this class of chalcogenide semiconductors is promising for thermoelectric applications. (orig.)

Thermoelectric converter for SP-100 space reactor power system

Science.gov (United States)

Terrill, W. R.; Haley, V. F.

1986-01-01

Conductively coupling the thermoelectric converter to the heat source and the radiator maximizes the utilization of the reactor and radiator temperatures and thereby minimizes the power system weight. This paper presents the design for the converter and the individual thermoelectric cells that are the building block modules for the converter. It also summarizes progress on the fabrication of initial cells and the results obtained from the preparation of a manufacturing plan. The design developed for the SP-100 system utilizes thermally conductive compliant pads that can absorb the displacement and distortion caused by the combinations of temperatures and thermal expansion coefficients. The converter and cell designs provided a 100 kWe system which met the system requirements. Initial cells were fabricated and tested.

Variations in thermoelectric power of thin monocrystalline films with conductivity

Science.gov (United States)

Tellier, C. R.; Tosser, A. J.; Hafid, L.

1980-12-01

Starting from the bi-dimensional model for grain boundaries in monocrystalline thin films, the difference in thermoelectric power is expressed in terms of conductivity and energy dependence of the bulk electronic mean free path U. A new procedure is suggested for measuring U.

Americium-241 radioisotope thermoelectric generator development for space applications

International Nuclear Information System (INIS)

Ambrosi, Richard; Williams, Hugo; Samara-Ratna, Piyal

2013-01-01

Space nuclear power systems are under development in the UK in collaboration with European partners as part of a European Space Agency (ESA) programme. Radioisotope thermoelectric generators (RTG) are an important element of this new capability in Europe. RTG systems being developed in Europe are targeting the 10 W electric to 50 W electric power generation range adopting a modular scalable approach to the design. Radiogenic decay heat from radioisotopes can be converted to electrical power by using appropriate semiconductor based thermoelectric materials. The plan for Europe is to develop radioisotope space nuclear power systems based on both thermoelectric and Stirling power conversion systems. Although primarily focused on delivering up to 50 W of electrical power, the European radioisotope thermoelectric system development programme is targeting americium-241 as a fuel source and is maximizing the use of commercially available thermoelectric manufacturing processes in order to accelerate the development of power conversion systems. The use of americium provides an economic solution at high isotopic purity and is product of a separation process from stored plutonium produced during the reprocessing of civil nuclear fuel. A laboratory prototype that uses electrical heating as a substitute for the radioisotope was developed to validate the designs. This prototype has now been tested. This paper outlines the requirements for a European americium-241 fuelled RTG, describes the most recent updates in system design and provides further insight into recent laboratory prototype test campaigns. (author)

Americium-241 radioisotope thermoelectric generator development for space applications

Energy Technology Data Exchange (ETDEWEB)

Ambrosi, Richard; Williams, Hugo; Samara-Ratna, Piyal, E-mail: rma8@le.ac.uk [University of Leicester, (United Kingdom); and others

2013-07-01

Space nuclear power systems are under development in the UK in collaboration with European partners as part of a European Space Agency (ESA) programme. Radioisotope thermoelectric generators (RTG) are an important element of this new capability in Europe. RTG systems being developed in Europe are targeting the 10 W electric to 50 W electric power generation range adopting a modular scalable approach to the design. Radiogenic decay heat from radioisotopes can be converted to electrical power by using appropriate semiconductor based thermoelectric materials. The plan for Europe is to develop radioisotope space nuclear power systems based on both thermoelectric and Stirling power conversion systems. Although primarily focused on delivering up to 50 W of electrical power, the European radioisotope thermoelectric system development programme is targeting americium-241 as a fuel source and is maximizing the use of commercially available thermoelectric manufacturing processes in order to accelerate the development of power conversion systems. The use of americium provides an economic solution at high isotopic purity and is product of a separation process from stored plutonium produced during the reprocessing of civil nuclear fuel. A laboratory prototype that uses electrical heating as a substitute for the radioisotope was developed to validate the designs. This prototype has now been tested. This paper outlines the requirements for a European americium-241 fuelled RTG, describes the most recent updates in system design and provides further insight into recent laboratory prototype test campaigns. (author)

Coal-water slurries containing petrochemicals to solve problems of air pollution by coal thermal power stations and boiler plants: An introductory review.

Science.gov (United States)

Dmitrienko, Margarita A; Strizhak, Pavel A

2018-02-01

This introductory study presents the analysis of the environmental, economic and energy performance indicators of burning high-potential coal water slurries containing petrochemicals (CWSP) instead of coal, fuel oil, and natural gas at typical thermal power stations (TPS) and a boiler plant. We focus on the most hazardous anthropogenic emissions of coal power industry: sulfur and nitrogen oxides. The research findings show that these emissions may be several times lower if coal and oil processing wastes are mixed with water as compared to the combustion of traditional pulverized coal, even of high grades. The study focuses on wastes, such as filter cakes, oil sludge, waste industrial oils, heavy coal-tar products, resins, etc., that are produced and stored in abundance. Their deep conversion is very rare due to low economic benefit. Effective ways are necessary to recover such industrial wastes. We present the cost assessment of the changes to the heat and power generation technologies that are required from typical power plants for switching from coal, fuel oil and natural gas to CWSPs based on coal and oil processing wastes. The corresponding technological changes pay off after a short time, ranging from several months to several years. The most promising components for CWSP production have been identified, which provide payback within a year. Among these are filter cakes (coal processing wastes), which are produced as a ready-made coal-water slurry fuel (a mixture of flocculants, water, and fine coal dust). These fuels have the least impact on the environment in terms of the emissions of sulfur and nitrogen oxides as well as fly ash. An important conclusion of the study is that using CWSPs based on filter cakes is worthwhile both as the main fuel for thermal power stations and boiler plants and as starting fuel. Copyright © 2017 Elsevier B.V. All rights reserved.

Influence of germanium nano-inclusions on the thermoelectric power factor of bulk bismuth telluride alloy

International Nuclear Information System (INIS)

Satyala, Nikhil; Zamanipour, Zahra; Norouzzadeh, Payam; Krasinski, Jerzy S.; Vashaee, Daryoosh; Tahmasbi Rad, Armin; Tayebi, Lobat

2014-01-01

Nanocomposite thermoelectric compound of bismuth telluride (Bi 2 Te 3 ) with 5 at. % germanium nano-inclusions was prepared via mechanically alloying and sintering techniques. The influence of Ge nano-inclusions and long duration annealing on the thermoelectric properties of nanostructured Bi 2 Te 3 were investigated. It was found that annealing has significant effect on the carrier concentration, Seebeck coefficient, and the power factor of the thermoelectric compound. The systematic heat treatment also reduced the density of donor type defects thereby decreasing the electron concentration. While the as-pressed nanocomposite materials showed n-type properties, it was observed that with the increase of annealing time, the nanocomposite gradually transformed to an abundantly hole-dominated (p-type) sample. The long duration annealing (∼500 h) resulted in a significantly enhanced electrical conductivity pertaining to the augmentation in the density and the structural properties of the sample. Therefore, a simultaneous enhancement in both electrical and Seebeck coefficient characteristics resulted in a remarkable increase in the thermoelectric power factor.

Si Thermoelectric Power Generator with an Unconventional Structure

Science.gov (United States)

Sakamoto, Tatsuya; Iida, Tsutomu; Ohno, Yota; Ishikawa, Masashi; Kogo, Yasuo; Hirayama, Naomi; Arai, Koya; Nakamura, Takashi; Nishio, Keishi; Takanashi, Yoshifumi

2014-06-01

We examine the mechanical stability of an unconventional Mg2Si thermoelectric generator (TEG) structure. In this structure, the angle θ between the thermoelectric (TE) chips and the heat sink is less than 90°. We examined the tolerance to an external force of various Mg2Si TEG structures using a finite-element method (FEM) with the ANSYS code. The output power of the TEGs was also measured. First, for the FEM analysis, the mechanical properties of sintered Mg2Si TE chips, such as the bending strength and Young's modulus, were measured. Then, two-dimensional (2D) TEG models with various values of θ (90°, 75°, 60°, 45°, 30°, 15°, and 0°) were constructed in ANSYS. The x and y axes were defined as being in the horizontal and vertical directions of the substrate, respectively. In the analysis, the maximum tensile stress in the chip when a constant load was applied to the TEG model in the x direction was determined. Based on the analytical results, an appropriate structure was selected and a module fabricated. For the TEG fabrication, eight TE chips, each with dimensions of 3 mm × 3 mm × 10 mm and consisting of Sb-doped n-Mg2Si prepared by a plasma-activated sintering process, were assembled such that two chips were connected in parallel, and four pairs of these were connected in series on a footprint of 46 mm × 12 mm. The measured power generation characteristics and temperature distribution with temperature differences between 873 K and 373 K are discussed.

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

Mercury emissions from South Africa’s coal-fired power stations

Directory of Open Access Journals (Sweden)

Belinda L. Garnham

2016-12-01

Full Text Available Mercury is a persistent and toxic substance that can be bio-accumulated in the food chain. Natural and anthropogenic sources contribute to the mercury emitted in the atmosphere. Eskom’s coal-fired power stations in South Africa contributed just under 93% of the total electricity produced in 2015 (Eskom 2016. Trace amounts of mercury can be found in coal, mostly combined with sulphur, and can be released into the atmosphere upon combustion. Coal-fired electricity generation plants are the highest contributors to mercury emissions in South Africa. A major factor affecting the amount of mercury emitted into the atmosphere is the type and efficiency of emission abatement equipment at a power station. Eskom employs particulate emission control technology at all its coal-fired power stations, and new power stations will also have sulphur dioxide abatement technology. A co-beneficial reduction of mercury emissions exists as a result of emission control technology. The amount of mercury emitted from each of Eskom’s coal-fired power stations is calculated, based on the amount of coal burnt and the mercury content in the coal. Emission Reduction Factors (ERF’s from two sources are taken into consideration to reflect the co-benefit received from the emission control technologies at the stations. Between 17 and 23 tons of mercury is calculated to have been emitted from Eskom’s coal-fired power stations in 2015. On completion of Eskom’s emission reduction plan, which includes fabric filter plant retrofits at two and a half stations and a flue gas desulphurisation retrofit at one power station, total mercury emissions from the fleet will potentially be reduced by 6-13% by 2026 relative to the baseline. Mercury emission reduction is perhaps currently not the most pressing air quality problem in South Africa. While the focus should then be on reducing emissions of other pollutants which have a greater impact on human health, mercury emission reduction

First-principles study of thermoelectric properties of CuI

International Nuclear Information System (INIS)

Yadav, Manoj K; Sanyal, Biplab

2014-01-01

Theoretical investigations of the thermoelectric properties of CuI have been carried out employing first-principles calculations followed by the calculations of transport coefficients based on Boltzmann transport theory. Among the three different phases of CuI, viz. zinc-blende, wurtzite and rock salt, the thermoelectric power factor is found to be the maximum for the rock salt phase. We have analysed the variations of Seebeck coefficients and thermoelectric power factors on the basis of calculated electronic structures near the valence band maxima of these phases. (papers)

Thermoelectrical power analysis of precipitation in 6013 aluminum alloy

International Nuclear Information System (INIS)

Abdala, M.R.W.S.; Garcia de Blas, J.C.; Barbosa, C.; Acselrad, O.

2008-01-01

The 6013 aluminum alloy was first developed for application in the aircraft industry and, more recently, as a replacement option for the use of the 6061 alloy in the automotive industry. The present work describes the evolution of the process of formation and dissolution of different kinds of precipitates in 6013 aluminum alloy, subjected to different conditions of heat treatment, using for this purpose measurements of thermoelectrical power, Vickers microhardness and differential scanning calorimeter (DSC). Although in the last years many works have been published on the use of thermoelectrical power (TEP) measurements for the analysis of precipitation process in traditional alloys such as 6061, there is still little information related to 6013 alloy. The results obtained are compared with a previous characterization work on the same alloy using transmission electron microscopy. It was observed that TEP measurements are very sensitive to precipitation phenomena in this alloy, and it has been found that there is an inverse relation between TEP and Vickers microhardness values, which allowed proposing a precipitation sequence for 6013 aluminum alloy

Coal-fired high performance power generating system. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-08-31

As a result of the investigations carried out during Phase 1 of the Engineering Development of Coal-Fired High-Performance Power Generation Systems (Combustion 2000), the UTRC-led Combustion 2000 Team is recommending the development of an advanced high performance power generation system (HIPPS) whose high efficiency and minimal pollutant emissions will enable the US to use its abundant coal resources to satisfy current and future demand for electric power. The high efficiency of the power plant, which is the key to minimizing the environmental impact of coal, can only be achieved using a modern gas turbine system. Minimization of emissions can be achieved by combustor design, and advanced air pollution control devices. The commercial plant design described herein is a combined cycle using either a frame-type gas turbine or an intercooled aeroderivative with clean air as the working fluid. The air is heated by a coal-fired high temperature advanced furnace (HITAF). The best performance from the cycle is achieved by using a modern aeroderivative gas turbine, such as the intercooled FT4000. A simplified schematic is shown. In the UTRC HIPPS, the conversion efficiency for the heavy frame gas turbine version will be 47.4% (HHV) compared to the approximately 35% that is achieved in conventional coal-fired plants. This cycle is based on a gas turbine operating at turbine inlet temperatures approaching 2,500 F. Using an aeroderivative type gas turbine, efficiencies of over 49% could be realized in advanced cycle configuration (Humid Air Turbine, or HAT). Performance of these power plants is given in a table.

Thermoelectric power measurements in liquid quenched amorphous alloys for FeZr and (FeCo)B

International Nuclear Information System (INIS)

Raza, S.M.; Naqvi, S.M.M.R.; Rizvi, S.; Hussain, A.; Rahman, F.

1999-01-01

Thermoelectric power (TEP) measurements have been carried out on six samples of LQA alloys from two different series, namely FeZr and Fe(Co)B, at relatively low temperatures. Thermoelectric power shows an overall Gaussian trend. The scattering centers are the major contributors to the residual TEP. Ziman theoretical model was used to estimate TEP. It was found that Ziman theory fails to account for quantitative TEP measurements at relatively low temperatures (77K< T<300K). (author)

AUTOMATIC BIOMASS BOILER WITH AN EXTERNAL THERMOELECTRIC GENERATOR

Directory of Open Access Journals (Sweden)

Marian Brázdil

2014-02-01

Full Text Available This paper presents the design and test results of an external thermoelectric generator that utilizes the waste heat from a small-scale domestic biomass boiler with nominal rated heat output of 25 kW. The low-temperature Bi2Te3 generator based on thermoelectric modules has the potential to recover waste heat from gas combustion products as effective energy. The small-scale generator is constructed from independent segments. Measurements have shown that up to 11 W of electricity can be generated by one segment. Higher output power can be achieved by linking thermoelectric segments. The maximum output power is given by the dew point of the flue gas. The electrical energy that is generated can be used, e.g., for power supply or for charging batteries. In the near future, thermoelectric generators could completely eliminate the dependence an automated domestic boiler system on the power supply from the electricity grid, and could ensure comfortable operation in the event of an unexpected power grid failure.

High-Performance Silicon-Germanium-Based Thermoelectric Modules for Gas Exhaust Energy Scavenging

Science.gov (United States)

Romanjek, K.; Vesin, S.; Aixala, L.; Baffie, T.; Bernard-Granger, G.; Dufourcq, J.

2015-06-01

Some of the energy used in transportation and industry is lost as heat, often at high-temperatures, during conversion processes. Thermoelectricity enables direct conversion of heat into electricity, and is an alternative to the waste-heat-recovery technology currently used, for example turbines and other types of thermodynamic cycling. The performance of thermoelectric (TE) materials and modules has improved continuously in recent decades. In the high-temperature range ( T hot side > 500°C), silicon-germanium (SiGe) alloys are among the best TE materials reported in the literature. These materials are based on non-toxic elements. The Thermoelectrics Laboratory at CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives) has synthesized n and p-type SiGe pellets, manufactured TE modules, and integrated these into thermoelectric generators (TEG) which were tested on a dedicated bench with hot air as the source of heat. SiGe TE samples of diameter 60 mm were created by spark-plasma sintering. For n-type SiGe doped with phosphorus the peak thermoelectric figure of merit reached ZT = 1.0 at 700°C whereas for p-type SiGe doped with boron the peak was ZT = 0.75 at 700°C. Thus, state-of-the-art conversion efficiency was obtained while also achieving higher production throughput capacity than for competing processes. A standard deviation high reproducibility. A silver-paste-based brazing technique was used to assemble the TE elements into modules. This assembly technique afforded low and repeatable electrical contact resistance (high temperatures (up to 600°C), and thirty 20 mm × 20 mm TE modules were produced and tested. The results revealed the performance was reproducible, with power output reaching 1.9 ± 0.2 W for a 370 degree temperature difference. When the temperature difference was increased to 500°C, electrical power output increased to >3.6 W. An air-water heat exchanger was developed and 30 TE modules were clamped and connected electrically

The development of a thermoelectric power generator dedicated to stove-fireplaces with heat accumulation systems

International Nuclear Information System (INIS)

Sornek, Krzysztof; Filipowicz, Mariusz; Rzepka, Kamila

2016-01-01

Highlights: • Application of thermoelectric generators in the stove-fireplace with accumulation. • Construction of the thermoelectric generator is limited by the heat accumulation. • Variants of the heat exchanger’s construction are discussed. • The control method is related on velocity of flue gas and water cooling. • The power limit of 30 W for self-sufficient operation is sufficient. - Abstract: A significant part of the world’s population (about 40%) cooks their meals and provides heating for their homes using wood-burning heating devices. Due to the relatively low cost of fuel and their aesthetic design, solid fuel stoves capable of heat accumulation are convenient and common. The use of dedicated small-scale power generators provides also additional benefits. This paper presents the results of a study conducted to verify the possibility of generating power using stove-fireplaces with heat accumulation systems. In such units, the temperature of the flue gas should be kept at a certain level for the purposes of storing heat, which results from certain limitations of the thermoelectric generators. To verify the possibility of applying thermoelectric modules in such heating devices, a dedicated system with thermoelectric generators was selected from among various microcogeneration systems and implemented. Three types of heat exchangers were studied and the most efficient unit was selected for further testing. Two types of generators, with maximum operating temperatures of 320 and 175 °C, were compared. Subsequently, the characteristics of the latter were determined. The conducted tests allowed to determine the performance and the total efficiency of the generators that were used. It has been demonstrated that the maximum power of the generator would not exceed ca. 30 W e and that there is no economic justification for such a device. However, providing a self-powered and self-sufficient operation of stove-fireplaces with heat accumulation systems

Heat-Pipe-Associated Localized Thermoelectric Power Generation System

Science.gov (United States)

Kim, Pan-Jo; Rhi, Seok-Ho; Lee, Kye-Bock; Hwang, Hyun-Chang; Lee, Ji-Su; Jang, Ju-Chan; Lee, Wook-Hyun; Lee, Ki-Woo

2014-06-01

The present study focused on how to improve the maximum power output of a thermoelectric generator (TEG) system and move heat to any suitable space using a TEG associated with a loop thermosyphon (loop-type heat pipe). An experimental study was carried out to investigate the power output, the temperature difference of the thermoelectric module (TEM), and the heat transfer performance associated with the characteristic of the researched heat pipe. Currently, internal combustion engines lose more than 35% of their fuel energy as recyclable heat in the exhaust gas, but it is not easy to recycle waste heat using TEGs because of the limited space in vehicles. There are various advantages to use of TEGs over other power sources, such as the absence of moving parts, a long lifetime, and a compact system configuration. The present study presents a novel TEG concept to transfer heat from the heat source to the sink. This technology can transfer waste heat to any location. This simple and novel design for a TEG can be applied to future hybrid cars. The present TEG system with a heat pipe can transfer heat and generate power of around 1.8 V with T TEM = 58°C. The heat transfer performance of a loop-type heat pipe with various working fluids was investigated, with water at high heat flux (90 W) and 0.05% TiO2 nanofluid at low heat flux (30 W to 70 W) showing the best performance in terms of power generation. The heat pipe can transfer the heat to any location where the TEM is installed.

Sulfur dioxide concentrations near thermoelectric power plant of Rossano Calabro (Italy)

International Nuclear Information System (INIS)

Florio, G.

1991-01-01

This article presents the results of a one-year atmospheric sulfur dioxide concentration monitoring campaign conducted with the use of five detection stations situated near the 320 MW thermoelectric power plant serving the coastal town of Rossano Calabro (population 50,000). Apart from the analysis of sulfur dioxide concentrations, a meteorological study was carried out based on anemological data. Comparisons were made with reference to the relevant legal standards. It was thus possible to ascertain that air quality near the power station is quite high. Nevertheless, it should be pointed out that, due to the particular local meteorological situation strongly turbulent sea breezes, new detection stations should be opened in this area which may undergo significant industrial development

Sulfur dioxide concentrations near thermoelectric power plant of Rossano Calabro (Italy)

Energy Technology Data Exchange (ETDEWEB)

Florio, G. (Calabria Univ., Arcavacata di Rende (Italy). Dipt. di Meccanica)

This article presents the results of a one-year atmospheric sulfur dioxide concentration monitoring campaign conducted with the use of five detection stations situated near the 320 MW thermoelectric power plant serving the coastal town of Rossano Calabro (population 50,000). Apart from the analysis of sulfur dioxide concentrations, a meteorological study was carried out based on anemological data. Comparisons were made with reference to the relevant legal standards. It was thus possible to ascertain that air quality near the power station is quite high. Nevertheless, it should be pointed out that, due to the particular local meteorological situation strongly turbulent sea breezes, new detection stations should be opened in this area which may undergo significant industrial development.

An automated thermoelectric power apparatus using electro-optic relays

International Nuclear Information System (INIS)

Chakravarti, A.; Ranganathan, R.

1992-01-01

We report the design and construction of a thermoelectric power apparatus using home-made electro-optic relays with Z-80A microprocessor for automatic data acquisition and control. The advantages of such relays made out of LED-LDR combinations for the measurement of ΔE and ΔT are discussed in details. (author). 7 refs., 5 figs

Life cycle assessment of solar aided coal-fired power system with and without heat storage

International Nuclear Information System (INIS)

Zhai, Rongrong; Li, Chao; Chen, Ying; Yang, Yongping; Patchigolla, Kumar; Oakey, John E.

2016-01-01

Highlights: • The comprehensive performances of three kinds of different systems were compared through LCA. • The comprehensive results of all systems were evaluated by grey relation theory. • The effects of life span, coal price, and solar collector field cost, among other factors, on the results were explored. - Abstract: Pollutant emissions from coal-fired power system have been receiving increasing attention over the past few years. Integration of solar thermal energy can greatly reduce pollutant emissions from these power stations. The performances of coal-fired power system (S1), solar aided coal-fired power system with thermal storage (S2), and solar aided coal-fired power system without thermal storage (S3) with three capacities of each kind of system (i.e., nine subsystems) were analyzed over the entire life span. The pollutant emissions and primary energy consumptions (PECs) of S1, S2, and S3 were estimated using life cycle assessment (LCA). The evaluation value of global warming potential (GWP), acidification potential (AP), respiratory effects potential (REP) and PEC were obtained based on the LCA results. Furthermore, the system investments were estimated, and grey relation theory was used to evaluate the performance of the three types of systems comprehensively. Finally, in order to find the effect of some main factors on the solar aided coal-fired power system (SACFPS), uncertainty analysis has been carried out. The LCA results show that the pollutant emissions and PEC mainly take place in the fuel processing and operation stages for all three system types, and S2 performs the best among the three systems based on the grey relation analysis results. And the uncertainty analysis shows that with longer life span, the power system have better performance; with higher coal price, the power system will have worse performance; with lower solar collector field cost, the solar aided coal-fired power system will be more profitable than the base

Thermal Stress Analysis and Structure Parameter Selection for a Bi2Te3-Based Thermoelectric Module

Science.gov (United States)

Gao, Jun-Ling; Du, Qun-Gui; Zhang, Xiao-Dan; Jiang, Xin-Qiang

2011-05-01

The output power and conversion efficiency of thermoelectric modules (TEMs) are mainly determined by their material properties, i.e., Seebeck coefficient, electrical resistivity, and thermal conductivity. In practical applications, due to the influence of the harsh environment, the mechanical properties of TEMs should also be considered. Using the finite-element analysis (FEA) model in ANSYS software, we present the thermal stress distribution of a TEM based on the anisotropic mechanical properties and thermoelectric properties of hot-pressed materials. By analyzing the possibilities of damage along the cleavage plane of Bi2Te3-based thermoelectric materials and by optimizing the structure parameters, a TEM with better mechanical performance is obtained. Thus, a direction for improving the thermal stress resistance of TEMs is presented.

Coal-Powered Electric Generating Unit Efficiency and Reliability Dialogue: Summary Report

Energy Technology Data Exchange (ETDEWEB)

Taylor, Emmanuel [Energetics, Inc., Columbia, MD (United States)

2018-02-01

findings and research suggestions discussed at the event. Discussions at the workshop will aid DOE in developing a set of distinct initiatives that can be pursued by government and industry to realize promising technological pursuits. DOE plans to use the results of the Dialogue coupled with ongoing technical analysis of efficiency opportunities within the coal-fired fleet, and additional studies to develop a comprehensive strategy for capitalizing on thermal efficiency improvements. Expected Power Plant Efficiency Improvements include developing cost-effective, efficient, and reliable technologies for boilers, turbines, and sensors and controls to improve the reliability and efficiency of existing coal-based power plants. The Office of Fossil Energy at DOE plans to work with industry to develop knowledge pertaining to advanced technologies and systems that industry can subsequently develop. These technologies and systems will increase reliability, add operational flexibility and improve efficiency, thereby providing more robust power generation infrastructure. The following table lists the research suggestions and questions for further investigation that were identified by participants in each session of the dialogue.

Maximum Power Point Tracking Control of a Thermoelectric Generation System Using the Extremum Seeking Control Method

Directory of Open Access Journals (Sweden)

Ssennoga Twaha

2017-12-01

Full Text Available This study proposes and implements maximum power Point Tracking (MPPT control on thermoelectric generation system using an extremum seeking control (ESC algorithm. The MPPT is applied to guarantee maximum power extraction from the TEG system. The work has been carried out through modelling of thermoelectric generator/dc-dc converter system using Matlab/Simulink. The effectiveness of ESC technique has been assessed by comparing the results with those of the Perturb and Observe (P&O MPPT method under the same operating conditions. Results indicate that ESC MPPT method extracts more power than the P&O technique, where the output power of ESC technique is higher than that of P&O by 0.47 W or 6.1% at a hot side temperature of 200 °C. It is also noted that the ESC MPPT based model is almost fourfold faster than the P&O method. This is attributed to smaller MPPT circuit of ESC compared to that of P&O, hence we conclude that the ESC MPPT method outperforms the P&O technique.

A Techno-Economic Assessment of Hybrid Cooling Systems for Coal- and Natural-Gas-Fired Power Plants with and without Carbon Capture and Storage.

Science.gov (United States)

Zhai, Haibo; Rubin, Edward S

2016-04-05

Advanced cooling systems can be deployed to enhance the resilience of thermoelectric power generation systems. This study developed and applied a new power plant modeling option for a hybrid cooling system at coal- or natural-gas-fired power plants with and without amine-based carbon capture and storage (CCS) systems. The results of the plant-level analyses show that the performance and cost of hybrid cooling systems are affected by a range of environmental, technical, and economic parameters. In general, when hot periods last the entire summer, the wet unit of a hybrid cooling system needs to share about 30% of the total plant cooling load in order to minimize the overall system cost. CCS deployment can lead to a significant increase in the water use of hybrid cooling systems, depending on the level of CO2 capture. Compared to wet cooling systems, widespread applications of hybrid cooling systems can substantially reduce water use in the electric power sector with only a moderate increase in the plant-level cost of electricity generation.

Modeling and performance analysis of a concentrated photovoltaic–thermoelectric hybrid power generation system

International Nuclear Information System (INIS)

Lamba, Ravita; Kaushik, S.C.

2016-01-01

Highlights: • Thermodynamic model of concentrated photovoltaic–thermoelectric system is analysed. • Thomson effect reduces the power output of PV, TE and hybrid PV–TEG system. • Effect of thermocouple number, irradiance, PV and TE current have been studied. • The optimum concentration ratio for maximum power output has been found out. • The overall efficiency and power output of hybrid PV–TEG system has been improved. - Abstract: In this study, a thermodynamic model for analysing the performance of a concentrated photovoltaic–thermoelectric generator (CPV–TEG) hybrid system including Thomson effect in conjunction with Seebeck, Joule and Fourier heat conduction effects has been developed and simulated in MATALB environment. The expressions for calculating the temperature of photovoltaic (PV) module, hot and cold sides of thermoelectric (TE) module are derived analytically as well. The effect of concentration ratio, number of thermocouples in TE module, solar irradiance, PV module current and TE module current on power output and efficiency of the PV, TEG and hybrid PV–TEG system have been studied. The optimum concentration ratio corresponding to maximum power output of the hybrid system has been found out. It has been observed that by considering Thomson effect in TEG module, the power output of the PV, TE and hybrid PV–TEG systems decreases and at C = 1 and 5, it reduces the power output of hybrid system by 0.7% and 4.78% respectively. The results of this study may provide basis for performance optimization of a practical irreversible CPV–TEG hybrid system.

The prospects for hard coal as a fuel for the Polish power sector

International Nuclear Information System (INIS)

Kaminski, Jacek; KudeLko, Mariusz

2010-01-01

This paper presents the prospects for the development of the Polish hard coal sector from the perspective of the power sector. The most important issues determining the mid- and long-term future for domestic coal production are: (1) the development of the economy, hence the demand for electricity, (2) regulations (mostly environmental) affecting the power sector, (3) the competitiveness of coal-based technologies, and (4) the costs of domestic coal production. Since the range of issues and relations being considered is very broad, a specific method needs to be employed for the quantitative analysis. The tool applied in this study is the partial equilibrium model POWER-POL, in which both the coal and the power sectors are incorporated. The model focuses on energy-economy-environmental issues without capturing detailed macroeconomic links. The model was run under six scenario assumptions. The results show that the domestic coal sector should maintain its position as a key supplier of primary energy for the Polish power sector. However, the environmental regulations to which the domestic power sector has to conform will decrease the share of coal in the fuel-mix. Since the investment processes in this sector are usually long-term, the effects of changes will be noticeable from 2015 onwards. - Research highlights: →Application of the partial equilibrium model POWER-POL for a quantitative analysis. →Coal will maintain its dominant position in the Polish heat and electricity production fuel-mix at least up to 2020. →Attractiveness of domestic hard coal supplies will depend on the environmental regulations (mostly on the EU level) and development in the world coal market. →The first nuclear power plant will be put into operation in 2020.

Green power production by co-gasification of biomass in coal-fired oxygen-blown entrained-flow based IGCC processes

Energy Technology Data Exchange (ETDEWEB)

Van Ree, R; Korbee, R; De Smidt, R P; Jansen, D [ECN Fuels Conversion and Environment, Petten (Netherlands); Baumann, H R; Ullrich, N [Krupp Uhde, Dortmund (Germany); Haupt, G; Zimmerman, [Siemens, Erlangen (Germany)

1998-11-01

The use of coal for large scale power production meets a growing environmental concern. In spite of the fact that clean coal conversion technologies integrated with high-efficiency power production facilities, such as IGCC, are developed, the aim for sustainable development strives for a power production system based on renewable energy sources. One of the most promising renewable energy sources that can be used in the Netherlands is biomass, i.e. organic waste materials and/or energy crops. To accelerate the introduction of this material, in a technical and economically acceptable way, co-gasification with fossil fuels, in particular coal, in large scale IGCC processes is considered. In this paper the technical feasibility, economic profitability, and environmental acceptability of co-gasification of biomass in coal-fired oxygen-blown entrained-flow based IGM is discussed. Both a base-case coal-fired oxygen-blown entrained-flow based IGCC process - showing strong resemblance to the Puertollano IGCC plant in Spain - and three co-gasification concepts, viz.: (1) a concept with separate dry coal and biomass feeding systems, (2) a concept with a combined dry coal/biomass-derived pyrolysis char feeding system, and (3) a concept with parallel biomass pre-treatment/gasification and combined fuel gas clean-up/power production, were defined for further consideration. The base-case system and the co-gasification concepts as well are modelled in the flowsheet simulation package ASPEN{sup +}. Steady-state integral system calculations resulted in an overall net electrical plant efficiency for the base-case system of 50. 1 %LHV (48.3 %HHV). Replacing about 10 % of the total thermal plant input (coal) by biomass (willow) resulted in a decrease of the overall net electrical plant efficiency of 1.4 to 2.1 %-points LHV, avoided specific CO2 emissions of 40-49 g/kWh{sub e}, and total avoided CO2 emissions of about 129 to 159 kt/a, all depending on the co-gasification concept

Automatic coal sampling for thermoelectric power plants; some remarks on moisture

Energy Technology Data Exchange (ETDEWEB)

Tanzi, M.

1983-06-01

Some problems associated with automatic coal sampling are discussed, in particular the change in moisture content during transport to sampling station. The moisture level is reduced by crushing and air exposure. Possible solutions to the problems are outlined: reducing exposure to air; reducing the degree of pulverisation; and use of special crushing equipment.

Assessment on thermoelectric power factor in silicon nanowire networks

Energy Technology Data Exchange (ETDEWEB)

Lohn, Andrew J.; Kobayashi, Nobuhiko P. [Baskin School of Engineering, University of California Santa Cruz, CA (United States); Nanostructured Energy Conversion Technology and Research (NECTAR), Advanced Studies Laboratories, University of California Santa Cruz, NASA Ames Research Center, Moffett Field, CA (United States); Coleman, Elane; Tompa, Gary S. [Structured Materials Industries, Inc., Piscataway, NJ (United States)

2012-01-15

Thermoelectric devices based on three-dimensional networks of highly interconnected silicon nanowires were fabricated and the parameters that contribute to the power factor, namely the Seebeck coefficient and electrical conductivity were assessed. The large area (2 cm x 2 cm) devices were fabricated at low cost utilizing a highly scalable process involving silicon nanowires grown on steel substrates. Temperature dependence of the Seebeck coefficient was found to be weak over the range of 20-80 C at approximately -400 {mu}V/K for unintentionally doped devices and {+-}50 {mu}V/K for p-type and n-type devices, respectively. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Concentration of arsenic in underground and drinking water in Kostolac coal basin (northern-east Serbia, Yugoslavia)

International Nuclear Information System (INIS)

Panic, Lj.; Vlajkovic, M.

2002-01-01

Arsenic is a widespread element in nature. Increased amounts of arsenic in drinking water are appearing in regions and areas with intensive exploitation of coal ant it's combustion in thermoelectrical power plants (China, Taiwan). That is why we studied containment of arsenic in flood, drainage and underground waters from ash deposits of Kostolac thermoelectrical power plants, wells and local water system in Kostolac and four surrounding villages. Increased amounts of arsenic in ash (19-33 mg/kg), which is hydraulically transported from thermoelectrical power plants are causing contamination of underground waters under and near ash deposits (0.1-0.08 mg/l). However, increased amount of arsenic in those underground waters don't pollute wells for water supplying population with drinking water, because in these causes, amount's of arsenic found in examined areas are under 0.05 mg/l. We have concluded that despite increased amounts of arsenic in the ashes of thermoelectrical power plants, contamination of residents water supplying wells has not occurred for the last few decades, but the risk of that still exists. Therefore we suggest regular controls of arsenic containment in drinking water and further construction of regional water supply system. (author)

Natural radionuclides in coal and waste material originating from coal fired power plant

International Nuclear Information System (INIS)

Marovic, Gordana; Franic, Zdenko; Sencar, Jasminka; Petrinec, Branko; Bituh, Tomislav; Kovac, Jadranka

2008-01-01

This paper presents long-term investigations of natural radioactivity in coal, used for power production in the coal-fired power plant (CFPP) situated on the Adriatic coast, and resulting slag and ash. Activity concentrations of 40 K, 232 Th, 226 Ra and 238 U in used coal and resulting waste material have been measured for 25 years. As expected, it was demonstrated that the content of radionuclides in deposited bottom and filter ash material are closely related with radionuclide activity concentrations and mineral matter fraction in used coals. The external hazard index has been calculated and discussed for the slag and ash depository. During the first decade of operation of the CFPP has been used domestic coal produced in nearby area characterized by higher background radiation compared with the rest of Croatia. Therefore, the coal itself had relatively high 226 Ra and 238 U activity concentrations while potassium and thorium content was very low, 40 K activity concentrations being 2-9% and those of 232 Th 1-3% of total activity. As, in addition, the sulphur concentrations in coal were very high use of domestic coal was gradually abandoned till it was completely substituted by imported coal originated from various sources and of low natural radioactivity. Upon this, activity concentrations of uranium series radionuclides in deposited waste materials decreased significantly. Consequently, waste material i.e., slag and ash, generated in the last several years of coal fired power plant operation could be readily used in cement industry and as additive to other building materials, without any special restrictions according to the Croatian regulations dealing with building materials and European directives. (author)

Utilization of brown coal in FRG power plants

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1985-07-01

FRG methods are studied for utilizing brown coal in view of the development of Kansk-Achinsk brown coal deposits. The use of brown coal in FRG power plants has increased from 15% in 1950- 1960 to 85% (total output) in 1982, providing 79.4 TWh of electrical energy. The remainder was used for briquetting, pulverization and breeze coke. In 1982 nearly 100 million tons of brown coal were burned by six large power stations (rated capacity 11,400 MW) to produce nearly 80 billion kWh of energy. Measures are discussed taken to reduce slagging and to remove excessive moisture content. Problems are analyzed associated with increased contamination of the atmosphere in areas with high population density (412/km/sup 2/) and cost of suppression is reviewed. According to available data, the cost of preventive measures taken by FRG, USA, Japan and the Netherlands is equal to 30% of the total cost of the energy. The most critical problem is suppression of sulfur dioxide, either by dry or wet scrubbers or by the addition of dry dolomite or lime to the furnace (75% of all SO/sub 2/ emissions in FRG comes from power stations). A method is described developed by RWE based on a series of distribution headers in the upper part of combustion chambers. At best, 70-80% reduction can be achieved. 14 references.

Coal and nuclear power: Illinois' energy future

International Nuclear Information System (INIS)

1982-01-01

This conference was sponsored by the Energy Resources Center, University of Illinois at Chicago; the US Department of Energy; the Illinois Energy Resources Commission; and the Illinois Department of Energy and Natural Resources. The theme for the conference, Coal and Nuclear Power: Illinois' Energy Future, was based on two major observations: (1) Illinois has the largest reserves of bituminous coal of any state and is surpassed in total reserves only by North Dakota, and Montana; and (2) Illinois has made a heavy commitment to the use of nuclear power as a source of electrical power generation. Currently, nuclear power represents 30% of the electrical energy produced in the State. The primary objective of the 1982 conference was to review these two energy sources in view of the current energy policy of the Reagan Administration, and to examine the impact these policies have on the Midwest energy scene. The conference dealt with issues unique to Illinois as well as those facing the entire nation. A separate abstract was prepared for each of the 30 individual presentations

A thermoelectric power generating heat exchanger: Part I – Experimental realization

DEFF Research Database (Denmark)

Bjørk, Rasmus; Sarhadi, Ali; Pryds, Nini

2016-01-01

An experimental realization of a heat exchanger with commercial thermoelectric generators (TEGs) is presented. The power producing capabilities as a function of flow rate and temperature span are characterized for two different commercial heat transfer fluids and for three different thermal...

Nanostructured Thermoelectric Oxides for Energy Harvesting Applications

KAUST Repository

Abutaha, Anas I.

2015-11-24

As the world strives to adapt to the increasing demand for electrical power, sustainable energy sources are attracting significant interest. Around 60% of energy utilized in the world is wasted as heat. Different industrial processes, home heating, and exhausts in cars, all generate a huge amount of unused waste heat. With such a huge potential, there is also significant interest in discovering inexpensive technologies for power generation from waste heat. As a result, thermoelectric materials have become important for many renewable energy research programs. While significant advancements have been done in improving the thermoelectric properties of the conventional heavy-element based materials (such as Bi2Te3 and PbTe), high-temperature applications of thermoelectrics are still limited to one materials system, namely SiGe, since the traditional thermoelectric materials degrade and oxidize at high temperature. Therefore, oxide thermoelectrics emerge as a promising class of materials since they can operate athigher temperatures and in harsher environments compared to non-oxide thermoelectrics. Furthermore, oxides are abundant and friendly to the environment. Among oxides, crystalline SrTiO3 and ZnO are promising thermoelectric materials. The main objective of this work is therefore to pursue focused investigations of SrTiO3 and ZnO thin films and superlattices grown by pulsed laser deposition (PLD), with the goal of optimizing their thermoelectric properties by following different strategies. First, the effect of laser fluence on the thermoelectric properties of La doped epitaxial SrTiO3 films is discussed. Films grown at higher laser fluences exhibit better thermoelectric performance. Second, the role of crystal orientation in determining the thermoelectric properties of epitaxial Al doped ZnO (AZO) films is explained. Vertically aligned (c-axis) AZO films have superior thermoelectric properties compared to other films with different crystal orientations. Third

European coal technology applied by the Danish power companies

Energy Technology Data Exchange (ETDEWEB)

Frydenberg, B. [Elsamprojekt A/S, Fredericia (Denmark)

1996-12-31

The development of coal-fired power plants has shown remarkable improvements with regard to efficiency and cleaner technology, and as coal remains the most important fuel for electric power production, it is important to make use of this technological development to reduce CO{sub 2} emissions. Of the three available technologies: Integrated Coal Gasification and Combined Cycle, Fluid Bed Combustion and Pulverised Coal with Ultra Supercritical Steam Data, the technology chosen by I/S ELSAM is the PC-USC with power production efficiencies growing from 45% to 50%. 5 figs., 1 tab.

Thermoelectricity in liquid crystals

Science.gov (United States)

Mohd Said, Suhana; Nordin, Abdul Rahman; Abdullah, Norbani; Balamurugan, S.

2015-09-01

The thermoelectric effect, also known as the Seebeck effect, describes the conversion of a temperature gradient into electricity. A Figure of Merit (ZT) is used to describe the thermoelectric ability of a material. It is directly dependent on its Seebeck coefficient and electrical conductivity, and inversely dependent on its thermal conductivity. There is usually a compromise between these parameters, which limit the performance of thermoelectric materials. The current achievement for ZT~2.2 falls short of the expected threshold of ZT=3 to allow its viability in commercial applications. In recent times, advances in organic thermoelectrics been significant, improving by over 3 orders of magnitude over a period of about 10 years. Liquid crystals are newly investigated as candidate thermoelectric materials, given their low thermal conductivity, inherent ordering, and in some cases, reasonable electrical conductivity. In this work the thermoelectric behaviour of a discotic liquid crystal, is discussed. The DLC was filled into cells coated with a charge injector, and an alignment of the columnar axis perpendicular to the substrate was allowed to form. This thermoelectric behavior can be correlated to the order-disorder transition. A reasonable thermoelectric power in the liquid crystal temperature regime was noted. In summary, thermoelectric liquid crystals may have the potential to be utilised in flexible devices, as a standalone power source.

Study on heat pipe assisted thermoelectric power generation system from exhaust gas

Science.gov (United States)

Chi, Ri-Guang; Park, Jong-Chan; Rhi, Seok-Ho; Lee, Kye-Bock

2017-11-01

Currently, most fuel consumed by vehicles is released to the environment as thermal energy through the exhaust pipe. Environmentally friendly vehicle technology needs new methods to increase the recycling efficiency of waste exhaust thermal energy. The present study investigated how to improve the maximum power output of a TEG (Thermoelectric generator) system assisted with a heat pipe. Conventionally, the driving energy efficiency of an internal combustion engine is approximately less than 35%. TEG with Seebeck elements is a new idea for recycling waste exhaust heat energy. The TEG system can efficiently utilize low temperature waste heat, such as industrial waste heat and solar energy. In addition, the heat pipe can transfer heat from the automobile's exhaust gas to a TEG. To improve the efficiency of the thermal power generation system with a heat pipe, effects of various parameters, such as inclination angle, charged amount of the heat pipe, condenser temperature, and size of the TEM (thermoelectric element), were investigated. Experimental studies, CFD simulation, and the theoretical approach to thermoelectric modules were carried out, and the TEG system with heat pipe (15-20% charged, 20°-30° inclined configuration) showed the best performance.

Electrochemically deposited BiTe-based nano wires for thermoelectric applications

International Nuclear Information System (INIS)

Inn-Khuan, N.; Kuan-Ying, K.; Che Zuraini Che Abdul Rahman; Nur Ubaidah Saidin; Suhaila Hani Ilias; Thye-Foo, C.

2013-01-01

Full-text: Nano structured materials systems such as thin-films and nano wires (NWs) are promising for thermoelectric power generation and refrigeration compared to traditional counterparts in bulk, due to their enhanced thermoelectric figures-of-merit. BiTe and its derivative compounds, in particular, are well-known for their near-room temperature thermoelectric performance. In this work, both the binary and ternary BiTe-based nano wires namely, BiTe and BiSbTe, were synthesized using template-assisted electrodeposition. Diameters of the nano wires were controlled by the pore sizes of the anodised alumina (AAO) templates used. Systematic study on the compositional change as a function of applied potential was carried out via Linear Sweep Voltametry (LSV). Chemical compositions of the nano wires were studied using Energy Dispersive X-ray Spectrometry (EDXS) and their microstructures evaluated using diffraction and imaging techniques. Results from chemical analysis on the nano wires indicated that while the Sb content in BiSbTe nano wires increased with more negative deposition potentials, the formation of Te 0 and Bi 2 Te 3 were favorable at more positive potentials. (author)

Low-temperature thermoelectric power factor enhancement by controlling nanoparticle size distribution.

Science.gov (United States)

Zebarjadi, Mona; Esfarjani, Keivan; Bian, Zhixi; Shakouri, Ali

2011-01-12

Coherent potential approximation is used to study the effect of adding doped spherical nanoparticles inside a host matrix on the thermoelectric properties. This takes into account electron multiple scatterings that are important in samples with relatively high volume fraction of nanoparticles (>1%). We show that with large fraction of uniform small size nanoparticles (∼1 nm), the power factor can be enhanced significantly. The improvement could be large (up to 450% for GaAs) especially at low temperatures when the mobility is limited by impurity or nanoparticle scattering. The advantage of doping via embedded nanoparticles compared to the conventional shallow impurities is quantified. At the optimum thermoelectric power factor, the electrical conductivity of the nanoparticle-doped material is larger than that of impurity-doped one at the studied temperature range (50-500 K) whereas the Seebeck coefficient of the nanoparticle doped material is enhanced only at low temperatures (∼50 K).

Survey and analysis of environmental performance indicators applied to thermoelectric generation styles; Levantamento e analise de indicadores de desempenho ambiental aplicados a empreendimentos termeletricos

Energy Technology Data Exchange (ETDEWEB)

Freitas, Bruno Moreno Rodrigo de; Cardoso Junior, Ricardo Abranches Felix [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

2010-07-01

Country economic growth is proportional bond to it electric generation increasing capacity. Brazil, which has a power matrix predominantly renewable, currently is increasing generation, from thermoelectricity, due, mainly, to major facilities in relation to environmental licensing. Since this new Thermal Power Plants operating, tied to the generation with those ones already installed, will result in environmental impacts that must be properly controlled. Such control should follow the Environmental Performance Evaluation guidance, standardized by ABNT NBR ISO 14031/04. Therefore, the following work presents the main Environmental Performance Indicators applied to several thermoelectric generation styles (Oil, Natural Gas, Diesel, Mineral Coal, Biomass, Waste, Solar and Nuclear). (author)

Radiation exposure potential from coal-fired power plants in Romania

International Nuclear Information System (INIS)

Botezatu, E.; Grecea, C.; Botezatu, G.; Capitanu, O.; Peic, T.; Sandor, G.

1996-01-01

In the investigated power plants they burn brown coal, lignite and/or mixture of different kinds of coal: brown coal, lignite, pit coal, pitch coal, bituminous coal. The activity concentrations measured in the coal samples varied over two orders of magnitude. The natural radionuclide concentrations in fly ash are significantly higher than the corresponding Concentrations in the coal. The normalized discharged activities for the investigated power plants are much higher than those estimated in the UNSCEAR 1988 Report for typical old and modern plants. Firstly, accounting for this is the low ash retention efficiency of the particulate control devices of power stations, especially for the older ones, and secondly, the high ash content of the coal: 26-60%. The low quality of coal leads to the higher coal consumption; thus the combustion of up to 20.109 Kg of coal is required to produce 1 Gwa of electrical energy. As a result, the activities of radon-222 and of radon-220 released per Gwa have been assessed at 25 to 770 GBq. (author)

Development of a 0.1 kW thermoelectric power generator for military applications

International Nuclear Information System (INIS)

Menchen, W.R.

1986-01-01

A man-portable thermoelectric power source is being developed for the U.S. Army. Initially used as a dedicated power supply for the XM-21 Chemical Agent Alarm System, the set can also meet a variety of general purpose user requirements. Development of a thermoelectric power conversion device is being undertaken by the U.S. Army LABCOM Electronics Technology and Devices Laboratory to fill a need for a generator that is silent, lightweight, multi-fueled and reliable. The 0.1 kW Power Generator is rectangular in configuration and consists of a power module, electronic control assembly and fuel delivery system housed within a tubular structural frame. The generator operates on military fuels ranging from kerosene to diesel oil. Multi-fuel capability is achieved using an ultrasonic atomizer and regenerative burner developed specifically for this application. This paper provides the first public presentation of results achieved during the Advanced Development Phase of the 0.1 kW Power Generator. The development process is briefly traced with emphasis on a description of the system and test results obtained to date

Nuclear energy cost data base: A reference data base for nuclear and coal-fired powerplant power generation cost analysis

International Nuclear Information System (INIS)

1988-09-01

A reference data base and standard methodology are needed for performing comparative nuclear and fossil power generation cost analyses for the Department of Energy, Office of Nuclear Energy. This report contains such a methodology together with reference assumptions and data to be used with the methodology. It is intended to provide basic guidelines or a starting point for analyses and to serve as a focal point in establishing parameters and methods to be used in economic comparisons of nuclear systems with alternatives. The data base is applicable for economic comparisons of new base load light-water reactors on a once-through cycle, and high- and low-sulfur coal-fired plants, and oil- and natural gas-fired electric generating plants coming on line around the turn of the century. In addition to current generation light-water reactors and fossil fuel-fired plants, preliminary cost information is also presented on improved and advanced light-water reactors, liquid metal reactor plants and fuel cycle facilities. This report includes an updated data base containing proposed technical and economic assumptions to be used in analyses, discussions of a recommended methodology to be used in calculating power generation costs, a sample calculation for illustrative and benchmark purposes and projected power generation costs for fission and coal-fired alternatives. Effects of the 1986 Tax Reform Act are included. 126 refs., 17 figs., 47 tabs

A thermoelectric-conversion power supply system using a strontium heat source of high-level radioactive nuclear waste

International Nuclear Information System (INIS)

Chikazawa, Yoshitaka

2011-01-01

A thermoelectric-conversion power supply system with radioactive strontium in high-level radioactive waste has been proposed. A combination of Alkali Metal Thermo-Electric Conversion (AMTEC) and a strontium fluoride heat source can provide a compact and long-lived power supply system. A heat source design with strontium fluoride pin bundles with Hastelloy cladding and intermediate copper has been proposed. This design has taken heat transportation into consideration, and, in this regard, the feasibility has been confirmed by a three-dimensional thermal analysis using Star-CD code. This power supply system with an electric output of 1 MW can be arranged in a space of 50 m 2 and approximately 1.1 m height and can be operated for 15 years without refueling. This compact and long-lived power supply is suitable for powering sources for remote places and middle-sized ships. From the viewpoint of geological disposal of high-level waste, the proposed power supply system provides a financial base for strontium-cesium partitioning. That is, a combination of minor-actinide recycling and strontium-cesium partitioning can eliminate a large part of decay heat in high-level waste and thus can save much space for geological disposal. (author)

Mapping the impacts of thermoelectric power generation: a global, spatially explicit database

Science.gov (United States)

Raptis, Catherine; Pfister, Stephan

2017-04-01

Thermoelectric power generation is associated with environmental pressures resulting from emissions to air and water, as well as water consumption. The need to achieve global coverage in related studies has become pressing in view of climate change. At the same time, the ability to quantify impacts from power production on a high resolution remains pertinent, given their highly regionalized nature, particularly when it comes to water-related impacts. Efforts towards global coverage have increased in recent years, but most work on the impacts of global electricity production presents a coarse geographical differentiation. Over the past few years we have begun a concerted effort to create and make available a global georeferenced inventory of thermoelectric power plant operational characteristics and emissions, by modelling the relevant processes on the highest possible level: that of a generating unit. Our work extends and enhances a commercially available global power plant database, and so far includes: - Georeferencing the generating units and populating the gaps in their steam properties. - Identifying the cooling system for 92% of the global installed thermoelectric power capacity. - Using the completed steam property data, along with local environmental temperature data, to systematically solve the Rankine cycle for each generating unit, involving: i) distinguishing between simple, reheat, and cogenerative cycles, and accounting for particularities in nuclear power cycles; ii) accounting for the effect of different cooling systems (once-through, recirculating (wet tower), dry cooling) on the thermodynamic cycle. One of the direct outcomes of solving the Rankine cycle is the cycle efficiency, an indispensable parameter in any study related to power production, including the quantification of air emissions and water consumption. Another direct output, for those units employing once-through cooling, is the rate of heat rejection to water, which can lead to

Modeling, experiments and optimization of an on-pipe thermoelectric generator

International Nuclear Information System (INIS)

Chen, Jie; Zuo, Lei; Wu, Yongjia; Klein, Jackson

2016-01-01

Highlights: • A novel design of on-pipe thermoelectric generator using heat pipe. • A heat pipe is used and increases power output by more than 6 times. • Detailed system level modeling on the heat transfer and energy conversion. • Lab-based experiments shows that system can harvest more than 2 W of energy. • An optimization towards the design indicates further improvement can be achieved. - Abstract: A thermoelectric energy harvester composed of two thermoelectric modules, a wicked copper-water heat pipe, and finned heat sinks has been designed, modeled, and tested. The harvester is proposed to power sensor nodes on heating/cooling, steam, or exhaust pipes like these in power stations, chemical plants and vehicle systems. A model to analyze the heat transfer and thermoelectric performance of the energy harvesting system has been developed and validated against experiments. The results show that the model predicts the system power output and temperature response with reasonable accuracy. The model developed in this paper can be adapted for use with general heat sink, heat pipe, and thermoelectric systems. The design, incorporating a heat pipe and two 1.1″ by 1.1″ Bi_2Te_3 modules generates 2.25 W ± 0.13 W power output with a temperature difference of 128 °C ± 1.12 °C and source temperature of 246 °C ± 1.9 °C, which is more than enough to operate wireless sensors or some actuators. The use of a heat pipe in this design increased the power output by 6 times over conventional designs. Based on the model, further improvement of the power output and energy harvesting efficiency of the system has been suggested by optimizing the number of thermoelectric modules.

Experimental Investigation of a Temperature-Controlled Car Seat Powered by an Exhaust Thermoelectric Generator

Science.gov (United States)

Du, H.; Wang, Y. P.; Yuan, X. H.; Deng, Y. D.; Su, C. Q.

2016-03-01

To improve the riding comfort and rational utilization of the electrical energy captured by an automotive thermoelectric generator (ATEG), a temperature-controlled car seat was constructed to adjust the temperature of the car seat surface. Powered by the ATEG and the battery, the seat-embedded air conditioner can improve the riding comfort using a thermoelectric device to adjust the surface temperature of the seat, with an air duct to regulate the cold side and hot side of the thermoelectric device. The performance of the thermoelectric cooler (TEC) and theoretical analysis on the optimum state of the TEC device are put forward. To verify the rationality of the air duct design and to ensure sufficient air supply, the velocity field of the air duct system was obtained by means of the finite element method. To validate the reliability of the numerical simulation, the air velocity around the thermoelectric device was measured by a wind speed transmitter. The performance of the temperature-controlled car seat has been validated and is in good agreement with bench tests and real vehicle tests.

Determination of radioactive trace elements in ashes and fly-ashes from Brazilian coal-fired power plants

International Nuclear Information System (INIS)

Bellido, L.F.; de Castro Arezzo, B.

1984-01-01

The aim of this work was to apply a epithermal neutron activation technique to determine the uranium and thorium content in coal ashes and fly ashes from Brazilian coal-fired thermoelectric plants and to evaluate the contribution of these elements and their descendents to the environmental radioactivity. Brazil has adopted as short term policy the use of alcohol and coal as alternative sources of energy. With regard to coal, large deposits of this mineral are found in southern states but the serious problem of its utilization is the risk of environmental contamination which can reach dangerous levels because the industrial plants burn several million tons per year. Uranium and thorium contents, determined experimentally, are extrapolated for annual coal consumption and their amounts and the activity of the radium isotopes descendents released to the atmosphere are calculated. The significance of these values and problems in environmental pollution are discussed

Thermodynamic analyses of solar thermal gasification of coal for hybrid solar-fossil power and fuel production

International Nuclear Information System (INIS)

Ng, Yi Cheng; Lipiński, Wojciech

2012-01-01

Thermodynamic analyses are performed for solar thermal steam and dry gasification of coal. The selected types of coal are anthracite, bituminous, lignite and peat. Two model conversion paths are considered for each combination of the gasifying agent and the coal type: production of the synthesis gas with its subsequent use in a combined cycle power plant to generate power, and production of the synthesis gas with its subsequent use to produce gasoline via the Fischer–Tropsch synthesis. Replacement of a coal-fired 35% efficient Rankine cycle power plant and a combustion-based integrated gasification combined cycle power plant by a solar-based integrated gasification combined cycle power plant leads to the reduction in specific carbon dioxide emissions by at least 47% and 27%, respectively. Replacement of a conventional gasoline production process via coal gasification and a subsequent Fischer–Tropsch synthesis with gasoline production via solar thermal coal gasification with a subsequent Fischer–Tropsch synthesis leads to the reduction in specific carbon dioxide emissions by at least 39%. -- Highlights: ► Thermodynamic analyses for steam and dry gasification of coal are presented. ► Hybrid solar-fossil paths to power and fuels are compared to those using only combustion. ► Hybrid power production can reduce specific CO 2 emissions by more than 27%. ► Hybrid fuel production can reduce specific CO 2 emissions by more than 39%.

Performance Analysis of Thermoelectric Based Automotive Waste Heat Recovery System with Nanofluid Coolant

Directory of Open Access Journals (Sweden)

Zhi Li

2017-09-01

Full Text Available Output performance of a thermoelectric-based automotive waste heat recovery system with a nanofluid coolant is analyzed in this study. Comparison between Cu-Ethylene glycol (Cu-EG nanofluid coolant and ethylene glycol with water (EG-W coolant under equal mass flow rate indicates that Cu-EG nanofluid as a coolant can effectively improve power output and thermoelectric conversion efficiency for the system. Power output enhancement for a 3% concentration of nanofluid is 2.5–8 W (12.65–13.95% compared to EG-Water when inlet temperature of exhaust varies within 500–710 K. The increase of nanofluid concentration within a realizable range (6% has positive effect on output performance of the system. Study on the relationship between total area of thermoelectric modules (TEMs and output performance of the system indicates that optimal total area of TEMs exists for maximizing output performance of the system. Cu-EG nanofluid as coolant can decrease optimal total area of TEMs compared with EG-W, which will bring significant advantages for the optimization and arrangement of TEMs whether the system space is sufficient or not. Moreover, power output enhancement under Cu-EG nanofluid coolant is larger than that of EG-W coolant due to the increase of hot side heat transfer coefficient of TEMs.

Enhancement of thermoelectric power factor of Sr2CoMoO6 double perovskite by annealing in reducing atmosphere

Science.gov (United States)

Tanwar, Khagesh; Saxena, Mandvi; Maiti, Tanmoy

2017-10-01

In general, n-type thermoelectric materials are rather difficult to design. This study particularly pivoted on designing potential environmentally benign oxides based n-type thermoelectric material. We synthesized Sr2CoMoO6 (SCMO) polycrystalline ceramics via the solid-state synthesis route. XRD, SEM, and thermoelectric measurements were carried out for phase constitution, microstructure analysis, and to determine its potential for thermoelectric applications. As-sintered SCMO sample showed an insulator like behavior till 640 °C after which it exhibited an n-type non-degenerate semiconductor behavior followed by a p-n type conduction switching. To stabilize a high temperature n-type behavior, annealing of SCMO in reducing atmosphere (H2) at 1000 °C was carried out. After annealing, the SCMO demonstrated an n-type semiconductor behavior throughout the temperature range of measurement. The electrical conductivity (σ) and the power factor (S2σ) were found to be increased manifold in the annealed SCMO double perovskite.

Thermoelectric properties of an interacting quantum dot based heat engine

Science.gov (United States)

Erdman, Paolo Andrea; Mazza, Francesco; Bosisio, Riccardo; Benenti, Giuliano; Fazio, Rosario; Taddei, Fabio

2017-06-01

We study the thermoelectric properties and heat-to-work conversion performance of an interacting, multilevel quantum dot (QD) weakly coupled to electronic reservoirs. We focus on the sequential tunneling regime. The dynamics of the charge in the QD is studied by means of master equations for the probabilities of occupation. From here we compute the charge and heat currents in the linear response regime. Assuming a generic multiterminal setup, and for low temperatures (quantum limit), we obtain analytical expressions for the transport coefficients which account for the interplay between interactions (charging energy) and level quantization. In the case of systems with two and three terminals we derive formulas for the power factor Q and the figure of merit Z T for a QD-based heat engine, identifying optimal working conditions which maximize output power and efficiency of heat-to-work conversion. Beyond the linear response we concentrate on the two-terminal setup. We first study the thermoelectric nonlinear coefficients assessing the consequences of large temperature and voltage biases, focusing on the breakdown of the Onsager reciprocal relation between thermopower and Peltier coefficient. We then investigate the conditions which optimize the performance of a heat engine, finding that in the quantum limit output power and efficiency at maximum power can almost be simultaneously maximized by choosing appropriate values of electrochemical potential and bias voltage. At last we study how energy level degeneracy can increase the output power.

Effective use of electric power facilities and promotion of energy conservation

International Nuclear Information System (INIS)

Tokumitsu, Iwao

1999-01-01

The capacity of Japan's commercial electric power facilities has been increased to more than 200 million kw. In order to provide a stable supply of electric power to meet constantly fluctuaring electric power demands, Japan's power plants generate electricity using an optimal combination of facilities, with nuclear power and coal-fired thermoelectric power providing the base load supply. In the use of electric power, moreover, measures are being implemented to reduce generation costs, conserve energy, and cut carbon dioxide emissions by reducing maximum output and equalizing the load. This report presents information concerning measures for improving the efficiency of electric power facilities operation, equalizing the load and promoting energy conservation. (author)

Flexible power fabrics made of carbon nanotubes for harvesting thermoelectricity.

Science.gov (United States)

Kim, Suk Lae; Choi, Kyungwho; Tazebay, Abdullah; Yu, Choongho

2014-03-25

Thermoelectric energy conversion is very effective in capturing low-grade waste heat to supply electricity particularly to small devices such as sensors, wireless communication units, and wearable electronics. Conventional thermoelectric materials, however, are often inadequately brittle, expensive, toxic, and heavy. We developed both p- and n-type fabric-like flexible lightweight materials by functionalizing the large surfaces and junctions in carbon nanotube (CNT) mats. The poor thermopower and only p-type characteristics of typical CNTs have been converted into both p- and n-type with high thermopower. The changes in the electronic band diagrams of the CNTs were experimentally investigated, elucidating the carrier type and relatively large thermopower values. With our optimized device design to maximally utilize temperature gradients, an electrochromic glucose sensor was successfully operated without batteries or external power supplies, demonstrating self-powering capability. While our fundamental study provides a method of tailoring electronic transport properties, our device-level integration shows the feasibility of harvesting electrical energy by attaching the device to even curved surfaces like human bodies.

Appropriate feed-in tariff of solar–coal hybrid power plant for China’s Inner Mongolia Region

International Nuclear Information System (INIS)

Zhao, Yawen; Hong, Hui; Jin, Hongguang

2016-01-01

Highlights: • The potential for the first 10 MWe level solar–coal hybrid power plant is estimated. • Economic feasibility analysis is performed based on the discounted cash flow model. • The appropriate feed-in tariff prices of different scenarios are provided. • The results provide suggestions for the development of solar–coal hybrid technology. - Abstract: Middle-temperature solar heat can be used to preheat feed water before it enters the boiler in a coal-fired power plant. Previous studies have shown that this approach can improve the performance of coal-fired power plants. The present study estimates the first solar–coal hybrid power plant in the Inner Mongolia Region. It will have a potential net solar power output of 10 MW on the basis of the operating data of a traditional 200 MW coal-fired power plant. Economic feasibility analysis is then performed on the solar–coal hybrid power plant. The appropriate feed-in tariff prices are provided on the basis of different financing scenarios, solar field cost, collector area size, and other conditions. The results obtained in this study are expected to provide suggestions for the further development of solar–coal hybrid technology.

Observer and data-driven model based fault detection in Power Plant Coal Mills

DEFF Research Database (Denmark)

Fogh Odgaard, Peter; Lin, Bao; Jørgensen, Sten Bay

2008-01-01

model with motor power as the controlled variable, data-driven methods for fault detection are also investigated. Regression models that represent normal operating conditions (NOCs) are developed with both static and dynamic principal component analysis and partial least squares methods. The residual...... between process measurement and the NOC model prediction is used for fault detection. A hybrid approach, where a data-driven model is employed to derive an optimal unknown input observer, is also implemented. The three methods are evaluated with case studies on coal mill data, which includes a fault......This paper presents and compares model-based and data-driven fault detection approaches for coal mill systems. The first approach detects faults with an optimal unknown input observer developed from a simplified energy balance model. Due to the time-consuming effort in developing a first principles...

Environmental impacts of coal mine and thermal power plant to the surroundings of Barapukuria, Dinajpur, Bangladesh.

Science.gov (United States)

Hossain, Md Nazir; Paul, Shitangsu Kumar; Hasan, Md Muyeed

2015-04-01

The study was carried out to analyse the environmental impacts of coal mine and coal-based thermal power plant to the surrounding environment of Barapukuria, Dinajpur. The analyses of coal, water, soil and fly ash were carried out using standard sample testing methods. This study found that coal mining industry and coal-based thermal power plant have brought some environmental and socio-economic challenges to the adjacent areas such as soil, water and air pollution, subsidence of agricultural land and livelihood insecurity of inhabitants. The pH values, heavy metal, organic carbon and exchangeable cations of coal water treated in the farmland soil suggest that coal mining deteriorated the surrounding water and soil quality. The SO4(2-) concentration in water samples was beyond the range of World Health Organisation standard. Some physico-chemical properties such as pH, conductivity, moisture content, bulk density, unburned carbon content, specific gravity, water holding capacity, liquid and plastic limit were investigated on coal fly ash of Barapukuria thermal power plant. Air quality data provided by the Barapukuria Coal Mining Company Limited were contradictory with the result of interview with the miners and local inhabitants. However, coal potentially contributes to the development of economy of Bangladesh but coal mining deteriorates the environment by polluting air, water and soil. In general, this study includes comprehensive baseline data for decision makers to evaluate the feasibility of coal power industry at Barapukuria and the coalmine itself.

Novel Fuel Cells for Coal Based Systems

Energy Technology Data Exchange (ETDEWEB)

Thomas Tao

2011-12-31

The goal of this project was to acquire experimental data required to assess the feasibility of a Direct Coal power plant based upon an Electrochemical Looping (ECL) of Liquid Tin Anode Solid Oxide Fuel Cell (LTA-SOFC). The objective of Phase 1 was to experimentally characterize the interaction between the tin anode, coal fuel and cell component electrolyte, the fate of coal contaminants in a molten tin reactor (via chemistry) and their impact upon the YSZ electrolyte (via electrochemistry). The results of this work will provided the basis for further study in Phase 2. The objective of Phase 2 was to extend the study of coal impurities impact on fuel cell components other than electrolyte, more specifically to the anode current collector which is made of an electrically conducting ceramic jacket and broad based coal tin reduction. This work provided a basic proof-of-concept feasibility demonstration of the direct coal concept.

Power generation from chemically cleaned coals: do environmental benefits of firing cleaner coal outweigh environmental burden of cleaning?

DEFF Research Database (Denmark)

Ryberg, Morten W.; Owsianiak, Mikolaj; Laurent, Alexis

2015-01-01

Power generation from high-ash coals is a niche technology for power generation, but coal cleaning is deemed necessary to avoid problems associated with low combustion efficiencies and to minimize environmental burdens associated with emissions of pollutants originating from ash. Here, chemical...... beneficiation of coals using acid and alkali–acid leaching procedures is evaluated as a potential coal cleaning technology employing life cycle assessment (LCA). Taking into account the environmental benefits from firing cleaner coal in pulverized coal power plants and the environmental burden of the cleaning...... itself, it is demonstrated that for a wide range of cleaning procedures and types of coal, chemical cleaning generally performs worse than combustion of the raw coals and physical cleaning using dense medium separation. These findings apply for many relevant impact categories, including climate change...

Compatibility of Segments of Thermoelectric Generators

Science.gov (United States)

Snyder, G. Jeffrey; Ursell, Tristan

2009-01-01

A method of calculating (usually for the purpose of maximizing) the power-conversion efficiency of a segmented thermoelectric generator is based on equations derived from the fundamental equations of thermoelectricity. Because it is directly traceable to first principles, the method provides physical explanations in addition to predictions of phenomena involved in segmentation. In comparison with the finite-element method used heretofore to predict (without being able to explain) the behavior of a segmented thermoelectric generator, this method is much simpler to implement in practice: in particular, the efficiency of a segmented thermoelectric generator can be estimated by evaluating equations using only hand-held calculator with this method. In addition, the method provides for determination of cascading ratios. The concept of cascading is illustrated in the figure and the definition of the cascading ratio is defined in the figure caption. An important aspect of the method is its approach to the issue of compatibility among segments, in combination with introduction of the concept of compatibility within a segment. Prior approaches involved the use of only averaged material properties. Two materials in direct contact could be examined for compatibility with each other, but there was no general framework for analysis of compatibility. The present method establishes such a framework. The mathematical derivation of the method begins with the definition of reduced efficiency of a thermoelectric generator as the ratio between (1) its thermal-to-electric power-conversion efficiency and (2) its Carnot efficiency (the maximum efficiency theoretically attainable, given its hot- and cold-side temperatures). The derivation involves calculation of the reduced efficiency of a model thermoelectric generator for which the hot-side temperature is only infinitesimally greater than the cold-side temperature. The derivation includes consideration of the ratio (u) between the

Optimization of the Heat Exchangers of a Thermoelectric Generation System

Science.gov (United States)

Martínez, A.; Vián, J. G.; Astrain, D.; Rodríguez, A.; Berrio, I.

2010-09-01

The thermal resistances of the heat exchangers have a strong influence on the electric power produced by a thermoelectric generator. In this work, the heat exchangers of a thermoelectric generator have been optimized in order to maximize the electric power generated. This thermoelectric generator harnesses heat from the exhaust gas of a domestic gas boiler. Statistical design of experiments was used to assess the influence of five factors on both the electric power generated and the pressure drop in the chimney: height of the generator, number of modules per meter of generator height, length of the fins of the hot-side heat exchanger (HSHE), length of the gap between fins of the HSHE, and base thickness of the HSHE. The electric power has been calculated using a computational model, whereas Fluent computational fluid dynamics (CFD) has been used to obtain the thermal resistances of the heat exchangers and the pressure drop. Finally, the thermoelectric generator has been optimized, taking into account the restrictions on the pressure drop.

Some environmental aspects related to sulphur emissions during combustion of Bulgarian coals

International Nuclear Information System (INIS)

Vassileva, C.; Vassilev, S.

2004-01-01

The mechanism of S emissions and their capture during combustion of some Bulgarian coals (Maritza East, Maritza West, Sofia, Pernik, Bobov Dol, Balkan) was studied based on the phase-mineral transformations in the inorganic matter during gradual heating of these coals. It was found that: 1) the organic, elemental and sulphide S is released from coal at 200-700 0 C; 2) the volatile S is initially captured by intermediate Ca-, Mg-, K-, Na-, Fc-, and Ba-oxides (mainly from decomposed organic matter and carbonates) with formation of their sulphates at 200-1000 0 C; 3) the decomposition of original and newly-formed sulphates occurs at 800-1300 0 C and they are the major source of volatile SO 2 from stack emissions of thermoelectric power stations (TPSs). The described mechanism of S emissions and their capture indicates that the traditional pulverized combustion (1200-1600 0 C) of the high-sulphur Bulgarian coals in TPSs is inadequate from an environmental point of view and other alternatives should be applied. Some of them such as fluidized-bed combustion and selective blending of the coals are proposed

Control of the extraction, transport and quality of coal in sections in actual time intervals

Energy Technology Data Exchange (ETDEWEB)

Prochazka, P; Sladek, J

1981-01-01

This paper describes the design of a system for the automatic, semiautomatic and manual control of the extraction, transport and quality of the coal in two sections of the Severo-Cheshsk brown coal basin using computers. The coal in these sections is transported along a joint transport main line which consists of three conveyor lines to two grinding works and from there to 3 thermoelectric power plants. Based on information about the coal quality in the mining sections of individual excavators, about their productivity and about the throughput of the conveyor lines, the computer determines in a quite short time the maximally possible throughput of the conveyor lines for ensuring the required coal quality. Programs are written in the ALGOL language. The information in the SM-3 computer from the excavators will be transmitted using a Tesla Radom wireless communications apparatus through a JPR-12 computer. A terminal will be mounted on each excavator which will report to the computer the number of ledges subject to mining, the type of coal in them, the distance of the excavator from the coal loading point and the size of required and actual productivity of the excavator.

Heavy metal atmospheric emissions from coal-fired power plants - Assessment and uncertainties

International Nuclear Information System (INIS)

Lecuyer, I.; Ungar, A.; Peter, H.; Karl, U.

2004-01-01

Power generation using fossil fuel combustion (coal and fuel-oil) participates, with other sectors, to heavy metal atmospheric emissions. The dispersion of these hazardous pollutants throughout the environment is more and more regulated. In order to assess the annual flows emitted from EDF coal-fired power plants, a computerized tool has been developed, based on the methodology defined by IFARE/DFIU in 1997. The heavy metal partition factors within the plant unit are determined according to the type of unit and the coal characteristics. Heavy metals output flows, and especially those emitted with flue gas at the stack, are then deduced from the actual coal consumption and chemical composition. A first inventory of heavy metal emissions from EDF coal-fired power plants has been achieved for year 2001. Values are accurate (± 40 %) for nonvolatile elements (Cr, Cu, Co, Mn, Ni, V) and for PM 10 and PM 2.5 (particulate matter below 10 μm and 2.5 μm). The uncertainty is higher (± 80 %) for volatile elements (As, Pb, Zn). Excess indicative values are given for elements which are both volatile and at low concentrations in coal (Hg, Se, Cd). (author)

Passive flow heat exchanger simulation for power generation from solar pond using thermoelectric generators

Science.gov (United States)

Baharin, Nuraida'Aadilia; Arzami, Amir Afiq; Singh, Baljit; Remeli, Muhammad Fairuz; Tan, Lippong; Oberoi, Amandeep

2017-04-01

In this study, a thermoelectric generator heat exchanger system was designed and simulated for electricity generation from solar pond. A thermoelectric generator heat exchanger was studied by using Computational Fluid Dynamics to simulate flow and heat transfer. A thermoelectric generator heat exchanger designed for passive in-pond flow used in solar pond for electrical power generation. A simple analysis simulation was developed to obtain the amount of electricity generated at different conditions for hot temperatures of a solar pond at different flow rates. Results indicated that the system is capable of producing electricity. This study and design provides an alternative way to generate electricity from solar pond in tropical countries like Malaysia for possible renewable energy applications.

Thermoelectric properties and performance of flexible reduced graphene oxide films up to 3,000 K

Science.gov (United States)

Li, Tian; Pickel, Andrea D.; Yao, Yonggang; Chen, Yanan; Zeng, Yuqiang; Lacey, Steven D.; Li, Yiju; Wang, Yilin; Dai, Jiaqi; Wang, Yanbin; Yang, Bao; Fuhrer, Michael S.; Marconnet, Amy; Dames, Chris; Drew, Dennis H.; Hu, Liangbing

2018-02-01

The development of ultrahigh-temperature thermoelectric materials could enable thermoelectric topping of combustion power cycles as well as extending the range of direct thermoelectric power generation in concentrated solar power. However, thermoelectric operation temperatures have been restricted to under 1,500 K due to the lack of suitable materials. Here, we demonstrate a thermoelectric conversion material based on high-temperature reduced graphene oxide nanosheets that can perform reliably up to 3,000 K. After a reduction treatment at 3,300 K, the nanosheet film exhibits an increased conductivity to 4,000 S cm-1 at 3,000 K and a high power factor S2σ = 54.5 µW cm-1 K-2. We report measurements characterizing the film's thermoelectric properties up to 3,000 K. The reduced graphene oxide film also exhibits a high broadband radiation absorbance and can act as both a radiative receiver and a thermoelectric generator. The printable, lightweight and flexible film is attractive for system integration and scalable manufacturing.

A thermoelectric cap for seafloor hydrothermal vents

International Nuclear Information System (INIS)

Xie, Yu; Wu, Shi-jun; Yang, Can-jun

2016-01-01

Highlights: • We developed a thermoelectric cap (TC) to harvest hydrothermal energy. • The TC was deployed at a hydrothermal vent site near Kueishantao islet, Taiwan. • The TC monitored the temperature of the hydrothermal fluids during the field test. • The TC could make the thermal energy of hydrothermal fluids a viable power source. - Abstract: Long-term in situ monitoring is crucial to seafloor scientific investigations. One of the challenges of operating sensors in seabed is the lifespan of the sensors. Such sensors are commonly powered by batteries when other alternatives, such as tidal or solar energy, are unavailable. However, the batteries have a limited lifespan and must be recharged or replaced periodically, which is costly and impractical. A thermoelectric cap, which harvests the thermal energy of hydrothermal fluids through a conduction pipe and converts the heat to electrical energy by using thermoelectric generators, was developed to avoid these inconveniences. The thermoelectric cap was combined with a power and temperature measurement system that enables the thermoelectric cap to power a light-emitting diode lamp, an electronic load (60 Ω), and 16 thermocouples continuously. The thermoelectric cap was field tested at a shallow hydrothermal vent site near Kueishantao islet, which is located offshore of northeastern Taiwan. By using the thermal gradient between hydrothermal fluids and seawater, the thermoelectric cap obtained a sustained power of 0.2–0.5 W during the field test. The thermoelectric cap successfully powered the 16 thermocouples and recorded the temperature of the hydrothermal fluids during the entire field test. Our results show that the thermal energy of hydrothermal fluids can be an alternative renewable power source for oceanographic research.

Environmental impact assessment of coal power plants in operation

OpenAIRE

Bartan Ayfer; Kucukali Serhat; Ar Irfan

2017-01-01

Coal power plants constitute an important component of the energy mix in many countries. However, coal power plants can cause several environmental risks such as: climate change and biodiversity loss. In this study, a tool has been proposed to calculate the environmental impact of a coal-fired thermal power plant in operation by using multi-criteria scoring and fuzzy logic method. We take into account the following environmental parameters in our tool: CO, SO2, NOx, particulate matter, fly as...

Hinkley Point 'C' power station public enquiry: proof of evidence on coal fired power station sites

Energy Technology Data Exchange (ETDEWEB)

Fothergill, S.; Witt, S.

1988-11-01

The Coalfield Communities Campaign (CCC) has argued that if a new base-load power station is required it should be coal-fired rather than nuclear, and that it should use UK coal. Proposals for new power stations at both Hinkley Point and at Fawley have encountered very considerable local and regional opposition, and this is increasingly likely to be the case at many other sites especially in Southern England. In contrast the CCC has sought to demonstrate that its member authorities would generally welcome the development of new coal-fired capacity on appropriate sites within their areas. In particular, this proof establishes that there is a prima facie case for considering three sites - Thorpe Marsh, Hams Hall and Uskmouth - as potential locations for a new large coal-fired power station as an alternative to Hinkley Point C. The relevant local authorities have expressed their willingness to co-operate in more detailed planning or technical investigations to secure a coal-fired power station on these sites. The CCC considers this to be a major and unprecedented offer to the CEGB and its successor bodies, which could greatly speed the development of new power staion capacity and be of considerable economic and social benefit to coalfield communities.

Double quantum dot as a minimal thermoelectric generator

OpenAIRE

Donsa, S.; Andergassen, S.; Held, K.

2014-01-01

Based on numerical renormalization group calculations, we demonstrate that experimentally realized double quantum dots constitute a minimal thermoelectric generator. In the Kondo regime, one quantum dot acts as an n-type and the other one as a p-type thermoelectric device. Properly connected the double quantum dot provides a miniature power supply utilizing the thermal energy of the environment.

High Thermoelectric Power Factor Organic Thin Films through Combination of Nanotube Multilayer Assembly and Electrochemical Polymerization.

Science.gov (United States)

Culebras, Mario; Cho, Chungyeon; Krecker, Michelle; Smith, Ryan; Song, Yixuan; Gómez, Clara M; Cantarero, Andrés; Grunlan, Jaime C

2017-02-22

In an effort to produce effective thermoelectric nanocomposites with multiwalled carbon nanotubes (MWCNT), layer-by-layer assembly was combined with electrochemical polymerization to create synergy that would produce a high power factor. Nanolayers of MWCNT stabilized with poly(diallyldimethylammonium chloride) or sodium deoxycholate were alternately deposited from water. Poly(3,4-ethylene dioxythiophene) [PEDOT] was then synthesized electrochemically by using this MWCNT-based multilayer thin film as the working electrode. Microscopic images show a homogeneous distribution of PEDOT around the MWCNT. The electrical resistance, conductivity (σ) and Seebeck coefficient (S) were measured before and after the PEDOT polymerization. A 30 bilayer MWCNT film (<1 μm thick) infused with PEDOT is shown to achieve a power factor (PF = S 2 σ) of 155 μW/m K 2 , which is the highest value ever reported for a completely organic MWCNT-based material and competitive with lead telluride at room temperature. The ability of this MWCNT-PEDOT film to generate power was demonstrated with a cylindrical thermoelectric generator that produced 5.5 μW with a 30 K temperature differential. This unique nanocomposite, prepared from water with relatively inexpensive ingredients, should open up new opportunities to recycle waste heat in portable/wearable electronics and other applications where low weight and mechanical flexibility are needed.

CEZ utility's coal-fired power plants: towards a higher environmental friendliness

International Nuclear Information System (INIS)

Kindl, V.; Spilkova, T.; Vanousek, I.; Stehlik, J.

1996-01-01

Environmental efforts of the major Czech utility, CEZ a.s., are aimed at reducing air pollution arising from electricity and heat generating facilities. There are 3 main kinds of activity in this respect: phasing out of coal fired power plants; technological provisions to reduce emissions of particulate matter, sulfur dioxide, and nitrogen oxides from those coal fired units that are to remain in operation after 1998; and completion of the Temelin nuclear power plant. In 1995, emissions of particulate matter, sulfur dioxide, nitrogen oxides, and carbon monoxide from CEZ's coal fired power plants were 19%, 79%, 59%, and 60%, respectively, with respect to the situation in 1992. The break-down of electricity generation by CEZ facilities (in GWh) was as follows in 1995: hydroelectric power plants 1673, nuclear power plants 12230, coal fired power plants without desulfurization equipment 30181, and coal fired power plants with desulfurization equipment 2277. Provisions implemented to improve the environmental friendliness of the individual CEZ's coal fired power plants are described in detail. (P.A.). 5 tabs., 1 fig

Evaluation methods of solar contribution in solar aided coal-fired power generation system

International Nuclear Information System (INIS)

Zhu, Yong; Zhai, Rongrong; Zhao, Miaomiao; Yang, Yongping; Yan, Qin

2015-01-01

Highlights: • Five methods for evaluating solar contribution are analyzed. • Method based on the second law of thermodynamics and thermal economics is more suitable for SACPGS. • Providing reliable reference for the formulation of feed-in tariff policies in China. - Abstract: Solar aided coal-fired power plants utilize solar thermal energy to couple with coal-fired power plants of various types by adopting characteristics of different thermal needs of plants. In this way, the costly thermal storage system and power generating system will become unnecessary, meanwhile the intermittent and unsteady nature of power generation can be avoided. In addition, large-scale utilization of solar thermal power and energy saving can be achieved. With the ever-deepening analyses of solar aided coal-fired power plants, the contribution evaluating system of solar thermal power is worth further exploration. In this paper, five common evaluation methods of solar contribution are analyzed, and solar aided coal-fired power plants of 1000 MW, 600 MW and 330 MW are studied with these five methods in a comparative manner. Therefore, this study can serve as a theoretical reference for future research of evaluation methods and subsidies for new energy

Coal and nuclear power: Illinois' energy future

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

This conference was sponsored by the Energy Resources Center, University of Illinois at Chicago; the US Department of Energy; the Illinois Energy Resources Commission; and the Illinois Department of Energy and Natural Resources. The theme for the conference, Coal and Nuclear Power: Illinois' Energy Future, was based on two major observations: (1) Illinois has the largest reserves of bituminous coal of any state and is surpassed in total reserves only by North Dakota, and Montana; and (2) Illinois has made a heavy commitment to the use of nuclear power as a source of electrical power generation. Currently, nuclear power represents 30% of the electrical energy produced in the State. The primary objective of the 1982 conference was to review these two energy sources in view of the current energy policy of the Reagan Administration, and to examine the impact these policies have on the Midwest energy scene. The conference dealt with issues unique to Illinois as well as those facing the entire nation. A separate abstract was prepared for each of the 30 individual presentations.

The exergy underground coal gasification technology for power generation and chemical applications

Energy Technology Data Exchange (ETDEWEB)

Blinderman, M.S. [Ergo Exergy Technologies Inc., Montreal, PQ (Canada)

2006-07-01

Underground coal gasification (UCG) is a gasification process carried out in non-mined coal seams using injection and production wells drilled from the surface, converting coal in situ into a product gas usable for chemical processes and power generation. The UCG process developed, refined and practised by Ergo Exergy Technologies is called the Exergy UCG Technology or {epsilon}UCG{trademark} technology. This paper describes the technology and its applications. The {epsilon}UCG technology is being applied in numerous power generation and chemical projects worldwide, some of which are described. These include power projects in South Africa, India, Pakistan and Canada, as well as chemical projects in Australia and Canada. A number of {epsilon}UCG{trademark} based industrial projects are now at a feasibility usage in India, New Zealand, USA and Europe. An {epsilon}UCG{trademark} IGCC power plant will generate electricity at a much lower cost than existing fossil fuel power plants. CO{sub 2} emissions of the plant can be reduced to a level 55% less than those of a supercritical coal-fired plant and 25% less than the emissions of NG CC. 10 refs., 8 figs.

Thermoelectric converter for SP-100 space reactor power system

International Nuclear Information System (INIS)

Terrill, W.R.; Haley, V.F.

1986-01-01

Conductively coupling the thermoelectric converter to the heat source and the radiator maximizes the utilization of the reactor and radiator temperatures and thereby minimizes the power system weight. This paper presents the design for the converter and the individual thermoelectric cells that are the building block modules for the converter. It also summarizes progress on the fabrication of initial cells and the results obtained from the preparation of a manufacturing plan. The design developed for the SP-100 system utilizes thermally conductive compliant pads that can absorb the displacement and distortion caused by the combinations of temperatures and thermal expansion coefficients. The converter and cell designs provided a 100 kWe system which met the system requirements. Initial cells were fabricated and tested. The manufacturing plan showed that the chosen materials and processes are compatible with today's production techniques, that the production volume can readily be achieved and that the costs are reasonable

Isolation and application of SOX and NOX resistant microalgae in biofixation of CO2 from thermoelectricity plants

International Nuclear Information System (INIS)

Radmann, Elisangela Martha; Vieira Camerini, Felipe; Duarte Santos, Thaisa; Vieira Costa, Jorge Alberto

2011-01-01

Highlights: → Microalgae can help reduce global warming. → Synechococcus nidulans and Chlorella vulgaris were isolated in a thermoelectric plant. → Microalgae were compared with Spirulina and Scenedesmus obliquus for CO 2 fixation. → Microalgae were exposed to CO 2 , SO 2 and NO, simulating a gas from coal combustion. → C. vulgaris and Spirulina sp. showed 13.43% of maximum daily fixation. - Abstract: Microalgae have been studied for their potential use in foodstuffs, agriculture, in the treatment of wastewater and, in particular, in the reduction of atmospheric carbon dioxide, the main cause of global warming. Thermoelectricity plants account for 22% of CO 2 emitted into the atmosphere and native microalgae may be more tolerant to the gases emitted from burning fossil fuels. In the study presented here, microalgae were isolated from ponds next to a Thermoelectricity Plant, located in southern Brazil, and identified as Synechococcus nidulans and Chlorella vulgaris. The isolated microalgae were grown and compared with two different strains of microalgae, Spirulina sp. and Scenedesmus obliquus, for CO 2 biofixation. The microalgae were exposed to 12% CO 2 , 60 ppm of SO 2 and 100 ppm of NO, simulating a gas from coal combustion. The C. vulgaris had similar behavior to Spirulina sp., with 13.43% of maximum daily fixation. The microalgae with the greater fixing capacity were C. vulgaris and Spirulina sp. and these can be grown in electric power plants for CO 2 biofixation of the coal combustion gas, which would help reduce global warming.

The Czech base of hard coal, problems, possibilities for utilization

International Nuclear Information System (INIS)

Cermak, T.; Roubicek, V.

1993-01-01

The Czech coal and power engineering base is in a deep restructuring period now. The basic problems represents the changeover from the system of the centrally planned state economy to the market model of the energy resources mining, production and consumption. The Czech economy will have to face to up to now unknown competitive forces on the coal market in Europe where American, Canadian, Australian and South African coals compete. The paper discusses historical aspects of the development of the coal mining industry in the Czechoslavakia, the present coal preparation techniques for coking coals, the coking industry, and the utilization of brown coal. How to utilize the domestic coal base and coal generally is closely connected with the global restructuralization of the Czech economy. The most difficult step of this process is undoubtedly the adaptation of the Czech fuel and energy base to the market economy conditions

Evaluation criteria for enhanced solar–coal hybrid power plant performance

International Nuclear Information System (INIS)

Zhao, Yawen; Hong, Hui; Jin, Hongguang

2014-01-01

Attention has been directed toward hybridizing solar energy with fossil power plants since the 1990s to improve reliability and efficiency. Appropriate evaluation criteria were important in the design and optimization of solar–fossil hybrid systems. Two new criteria to evaluate the improved thermodynamic performances in a solar hybrid power plant were developed in this study. Correlations determined the main factors influencing the improved thermodynamic performances. The proposed criteria can be used to effectively integrate solar–coal hybridization systems. Typical 100 MW–1000 MW coal-fired power plants hybridized with solar heat at approximately 300 °C, which was used to preheat the feed water before entering the boiler, were evaluated using the criteria. The integration principle of solar–coal hybrid systems was also determined. The proposed evaluation criteria may be simple and reasonable for solar–coal hybrid systems with multi-energy input, thus directing system performance enhancement. - Highlights: • New criteria to evaluate the solar hybrid power plant were developed. • Typical solar–coal hybrid power plants were evaluated using the criteria. • The integration principle of solar–coal hybrid systems was determined. • The benefits of the solar–coal hybrid system are enhanced at lower solar radiation

Federal tax incentives affecting coal and nuclear power economics

International Nuclear Information System (INIS)

Chapman, D.

1982-01-01

This paper analyzes the effect of federal corporate income tax incentives on coal and nuclear power developments. It estimates (1) the magnitudes of tax incentives in relationship to utility costs, (2) the relative magnitude of benefits going to coal and nuclear facilities, and (3) the influence which the time paths of tax payments and after-tax net income have upon possible incentives for premature construction and excess capacity. Utility planners currently believe that nuclear power enjoys an after-tax competitive advantage over coal plants. Investigation of investment-related credits, deductions, and exclusions in the Internal Revenue Code shows that nuclear power enjoys a more favorable tax subsidy because of its greater capital intensity. In the absence of tax subsidies, no utility would prefer nuclear power to coal generation. Tax changes now under consideration could increase the tax benefits to both without disturbing the differential advantage held by nuclear power. 43 references, 2 figures, 4 tables

Object-Oriented Modeling of an Energy Harvesting System Based on Thermoelectric Generators

Science.gov (United States)

Nesarajah, Marco; Frey, Georg

This paper deals with the modeling of an energy harvesting system based on thermoelectric generators (TEG), and the validation of the model by means of a test bench. TEGs are capable to improve the overall energy efficiency of energy systems, e.g. combustion engines or heating systems, by using the remaining waste heat to generate electrical power. Previously, a component-oriented model of the TEG itself was developed in Modelica® language. With this model any TEG can be described and simulated given the material properties and the physical dimension. Now, this model was extended by the surrounding components to a complete model of a thermoelectric energy harvesting system. In addition to the TEG, the model contains the cooling system, the heat source, and the power electronics. To validate the simulation model, a test bench was built and installed on an oil-fired household heating system. The paper reports results of the measurements and discusses the validity of the developed simulation models. Furthermore, the efficiency of the proposed energy harvesting system is derived and possible improvements based on design variations tested in the simulation model are proposed.

Understanding coal quality and its relationship to power plant performance and costs

Energy Technology Data Exchange (ETDEWEB)

Jennison, K.D.; Stallard, G.S. [Black & Veatch International, Overland Park, KS (United States)

1995-12-01

The availability of reliable, reasonably priced energy is a necessary cornerstone for established and emerging economies. In addition to addressing coal quality issues strictly at a plant level, it is now prudent to consider long-term performance and economics of particular fuel sources to be selected in the light of system economics and reliability. In order to evaluate coal quality issues in a more comprehensive manner, it is important to develop both an approach and a set of tools which can support the various phases of the planning/analysis processes. The processes must consider the following: (1) Cost/availability of other potential coal supplies, including {open_quotes}raw{close_quotes} domestic sources, {open_quotes}cleaned {close_quotes} domestic sources, and other internationally marketed coals. (2) Power plant performance issues as function of plant design and fuel properties. (3) System expansion plans, candidate technologies, and associated capital and operating costs. (4) Projected load demand, for system and for individual units within the system. (5) Legislative issues such as environmental pressures, power purchase agreements, etc. which could alter the solution. (6) Economics of potential plans/strategies based on overall cost-effectiveness of the utility system, not just individual units. (7) Anticipated unit configuration, including addition of environmental control equipment or other repowering options. The Coal Quality Impact Model (CQIM{trademark}) is a PC-based computer program capable of predicting coal-related cost and performance impacts at electric power generating sites. The CQIM was developed for EPRI by Black & Veatch and represents over a decade of effort geared toward developing an extensible state-of-the-art coal quality assessment tool. This paper will introduce CQIM, its capabilities, and its application to Eastern European coal quality assessment needs.

Gas to Coal Competition in the U.S. Power Sector

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-06-01

With the newfound availability of natural gas due to the shale gas revolution in the United States, cheap gas now threatens coal’s longstanding position as the least costly fuel for generating electricity. But other factors besides cost come into play when deciding to switch from coal to gas. Electricity and gas transmission grid constraints, regulatory and contractual issues, as well as other factors determine the relative share of coal and gas in power generation. This paper analyzes competition between coal and gas for generating power in the United States and the factors explaining this dynamic. It also projects coal-to-gas switching in power generation for 18 states representing 75% of the surplus gas potential in the United States up to 2017, taking into consideration the impact of environmental legislation on retirement of coal-fired power plants.

Power generation from lignite coal in Bulgaria - problems and solutions

International Nuclear Information System (INIS)

Batov, S.; Gadjanov, P.; Panchev, T.

1997-01-01

The bulk of lignite coal produced in Bulgaria is used as fuel for the thermal power plants (TPP) built in Maritsa East coal field. A small part of it goes to production of briquettes and to fuel the auxiliary power plants of industrial enterprises. The total installed capacity of the power plants in the region of Maritsa East is 2490 MW, and the electric power generated by them is about 30% of the total power generated in the country. It should be noted that these power plants were subjected to a number of rehabilitations aiming to improve their technical and economic parameters. Irrespective of that, however, solution has still to be sought to a number of problems related to utilisation of the low-grade lignite coal for power generation. On the whole, they can be divided in the following groups: Those related to lignite coal mining can be referred to the first group. Lignite coal is mined in comparatively complicated mining and geological conditions characterized mainly by earth creep and deformation. The second group of problems is related to coal quality control. It is a fact of major significance that the quality indices of coal keep changing all the time in uneven steps without any definite laws to govern it. That creates hard problems in the process of coal transportation, crushing and combustion. The next group of problems concerns operation and upgrading of the power generation equipment. That applies especially to the existing boilers which bum low-grade fuel in order to improve their operation in terms of higher thermal efficiency, controllability, reliability, improved environmental indices, etc. An increasingly high importance is attached to environmental impact problems incident to lignite coal utilisation. Abatement of sulphur oxide emissions and dust pollution is a problem solution of which cannot wait. The possibilities for partial solution of the environmental problems through increasing the thermal efficiency of facilities at the thermal Power

Electronic structure of Rh-based CuRh0.9Mg0.1O2 oxide thermoelectrics

Science.gov (United States)

Vilmercati, P.; Martin, E.; Cheney, C. Parks; Bondino, F.; Magnano, E.; Parmigiani, F.; Sasagawa, T.; Mannella, N.

2013-03-01

The electronic structure of the Rh-based CuRh0.9Mg0.1O2 oxide thermoelectric compound has been studied with a multitechnique approach consisting of photoemission, x-ray absorption, and x-ray emission spectroscopies. The data indicate that the region of the valence band in the proximity of the Fermi level is dominated by Rh-derived states. These findings outline the importance of the electronic structure of the Rh ions for the large thermoelectric power in CuRh0.9Mg0.1O2 at high temperature.

Development of a coal quality analyzer for application to power plants based on laser-induced breakdown spectroscopy

Science.gov (United States)

Zhang, Lei; Gong, Yao; Li, Yufang; Wang, Xin; Fan, Juanjuan; Dong, Lei; Ma, Weiguang; Yin, Wangbao; Jia, Suotang

2015-11-01

It is vitally important for a power plant to determine the coal property rapidly to optimize the combustion process. In this work, a fully software-controlled laser-induced breakdown spectroscopy (LIBS) based coal quality analyzer comprising a LIBS apparatus, a sampling equipment, and a control module, has been designed for possible application to power plants for offering rapid and precise coal quality analysis results. A closed-loop feedback pulsed laser energy stabilization technology is proposed to stabilize the Nd: YAG laser output energy to a preset interval by using the detected laser energy signal so as to enhance the measurement stability and applied in a month-long monitoring experiment. The results show that the laser energy stability has been greatly reduced from ± 5.2% to ± 1.3%. In order to indicate the complex relationship between the concentrations of the analyte of interest and the corresponding plasma spectra, the support vector regression (SVR) is employed as a non-linear regression method. It is shown that this SVR method combined with principal component analysis (PCA) enables a significant improvement in cross-validation accuracy by using the calibration set of coal samples. The root mean square error for prediction of ash content, volatile matter content, and calorific value decreases from 2.74% to 1.82%, 1.69% to 1.22%, and 1.23 MJ/kg to 0.85 MJ/kg, respectively. Meanwhile, the corresponding average relative error of the predicted samples is reduced from 8.3% to 5.48%, 5.83% to 4.42%, and 5.4% to 3.68%, respectively. The enhanced levels of accuracy obtained with the SVR combined with PCA based calibration models open up avenues for prospective prediction in coal properties.

Increasing flexibility of coal power plant by control system modifications

Directory of Open Access Journals (Sweden)

Marušić Ante

2016-01-01

Full Text Available Expanding implementation of intermittent renewable energy sources has already started to change the role of thermal power plants in energy systems across Europe. Traditionally base load plants are now forced to operate as peaking plants. A familiar transition in upcoming years is expected in Croatia and coal power plant operators are preparing accordingly. To evaluate cycling capabilities and control system operation for flexible operation of selected 210 MW coal plant, series of tests with different load gradients were performed and results were thoroughly analyzed. Two possible “bottlenecks” are identified, thermal stress in superheater header, and achievable ramping rate considering operational limitations of coal feeders, firing system and evaporator dynamics. Several unexpected readings were observed, usually caused by malfunctioning sensors and equipment, resulting in unexpected oscillations of superheated steam temperature. Based on superheater geometry and experimental data, maximal steam temperature gradient during ramping was evaluated. Since thermal stress was well inside the safety margins, the simulation model of the whole boiler was used to evaluate achievable ramping on electric side.

Compliant Interfacial Layers in Thermoelectric Devices

Science.gov (United States)

Firdosy, Samad A. (Inventor); Li, Billy Chun-Yip (Inventor); Ravi, Vilupanur A. (Inventor); Fleurial, Jean-Pierre (Inventor); Caillat, Thierry (Inventor); Anjunyan, Harut (Inventor)

2017-01-01

A thermoelectric power generation device is disclosed using one or more mechanically compliant and thermally and electrically conductive layers at the thermoelectric material interfaces to accommodate high temperature differentials and stresses induced thereby. The compliant material may be metal foam or metal graphite composite (e.g. using nickel) and is particularly beneficial in high temperature thermoelectric generators employing Zintl thermoelectric materials. The compliant material may be disposed between the thermoelectric segments of the device or between a thermoelectric segment and the hot or cold side interconnect of the device.

Technical, environmental, and economic assessment of deploying advanced coal power technologies in the Chinese context

International Nuclear Information System (INIS)

Zhao Lifeng; Xiao Yunhan; Gallagher, Kelly Sims; Wang Bo; Xu Xiang

2008-01-01

The goal of this study is to evaluate the technical, environmental, and economic dimensions of deploying advanced coal-fired power technologies in China. In particular, we estimate the differences in capital cost and overall cost of electricity (COE) for a variety of advanced coal-power technologies based on the technological and economic levels in 2006 in China. This paper explores the economic gaps between Integrated Gasification Combined Cycle (IGCC) and other advanced coal power technologies, and compares 12 different power plant configurations using advanced coal power technologies. Super critical (SC) and ultra super critical (USC) pulverized coal (PC) power generation technologies coupled with pollution control technologies can meet the emission requirements. These technologies are highly efficient, technically mature, and cost-effective. From the point of view of efficiency, SC and USC units are good choices for power industry. The net plant efficiency for IGCC has reached 45%, and it has the best environmental performance overall. The cost of IGCC is much higher, however, than that of other power generation technologies, so the development of IGCC is slow throughout the world. Incentive policies are needed if IGCC is to be deployed in China

Experimental investigation of thermoelectric power generation versus coolant pumping power in a microchannel heat sink

DEFF Research Database (Denmark)

Kolaei, Alireza Rezania; Rosendahl, Lasse; Andreasen, Søren Juhl

2012-01-01

The coolant heat sinks in thermoelectric generators (TEG) play an important role in order to power generation in the energy systems. This paper explores the effective pumping power required for the TEGs cooling at five temperature difference of the hot and cold sides of the TEG. In addition......, the temperature distribution and the pressure drop in sample microchannels are considered at four sample coolant flow rates. The heat sink contains twenty plate-fin microchannels with hydraulic diameter equal to 0.93 mm. The experimental results show that there is a unique flow rate that gives maximum net-power...

Opto-thermoelectric nanotweezers

Science.gov (United States)

Lin, Linhan; Wang, Mingsong; Peng, Xiaolei; Lissek, Emanuel N.; Mao, Zhangming; Scarabelli, Leonardo; Adkins, Emily; Coskun, Sahin; Unalan, Husnu Emrah; Korgel, Brian A.; Liz-Marzán, Luis M.; Florin, Ernst-Ludwig; Zheng, Yuebing

2018-04-01

Optical manipulation of plasmonic nanoparticles provides opportunities for fundamental and technical innovation in nanophotonics. Optical heating arising from the photon-to-phonon conversion is considered as an intrinsic loss in metal nanoparticles, which limits their applications. We show here that this drawback can be turned into an advantage, by developing an extremely low-power optical tweezing technique, termed opto-thermoelectric nanotweezers. By optically heating a thermoplasmonic substrate, a light-directed thermoelectric field can be generated due to spatial separation of dissolved ions within the heating laser spot, which allows us to manipulate metal nanoparticles of a wide range of materials, sizes and shapes with single-particle resolution. In combination with dark-field optical imaging, nanoparticles can be selectively trapped and their spectroscopic response can be resolved in situ. With its simple optics, versatile low-power operation, applicability to diverse nanoparticles and tunable working wavelength, opto-thermoelectric nanotweezers will become a powerful tool in colloid science and nanotechnology.

Environmental externalities: Applying the concept to Asian coal-based power generation

International Nuclear Information System (INIS)

Szpunar, C.B.; Gillette, J.L.

1993-03-01

This report examines the concept of environmental externality. It discusses various factors -- the atmospheric transformations, relationship of point-source emissions to ambient air quality, dose-response relationships, applicable cause-and-effect principles, and risk and valuation research -- that are considered by a number of state utilities when they apply the environmental externality concept to energy resource planning. It describes a methodology developed by Argonne National Laboratory for general use in resource planning, in combination with traditional methods that consider the cost of electricity production. Finally, it shows how the methodology can be applied in Indonesia, Thailand, and Taiwan to potential coal-fired power plant projects that will make use of clean coal technologies

Environmental externalities: Applying the concept to Asian coal-based power generation

Energy Technology Data Exchange (ETDEWEB)

Szpunar, C.B.; Gillette, J.L.

1993-03-01

This report examines the concept of environmental externality. It discusses various factors -- the atmospheric transformations, relationship of point-source emissions to ambient air quality, dose-response relationships, applicable cause-and-effect principles, and risk and valuation research -- that are considered by a number of state utilities when they apply the environmental externality concept to energy resource planning. It describes a methodology developed by Argonne National Laboratory for general use in resource planning, in combination with traditional methods that consider the cost of electricity production. Finally, it shows how the methodology can be applied in Indonesia, Thailand, and Taiwan to potential coal-fired power plant projects that will make use of clean coal technologies.

A Low-Cost Production Method of FeSi2 Power Generation Thermoelectric Modules

Science.gov (United States)

Inoue, Hiroyuki; Kobayashi, Takahide; Kato, Masahiko; Yoneda, Seiji

2016-03-01

A method is proposed to reduce the production cost of power generation thermoelectric modules. FeSi2 is employed as the thermoelectric material because of its low cost, low environmental load, and oxidation resistance. The raw materials were prepared in the composition of Fe0.96Si2.1Co0.04 for n-type and Fe0.92Si2.1Mn0.08 for p-type, which were added with 0.5 wt.% Cu as the starting materials. They were sintered without pressure at 1446 K to be formed into elements. The Seebeck coefficient and resistivity at room temperature were determined to be -182 μV/K and 0.13 mΩm for n-type, and 338 μV/K and 1.13 mΩm for p-type, respectively. The brazing conditions of the direct joining between the element and the solder were examined. Pastes of BNi-6, BNi-7 or TB-608T were tried as the solder. TB-608T was useable for metallizing of insulation substrates and joining of thermoelectric elements in order to manufacture thermoelectric modules. The joining strength was determined to be 50 MPa between the alumina plate and the elements. No mechanical failure was observed in the modules after repetition of 10 or more exposures to a heat source of 670 K. No change was found in the internal resistance. The present production method will provide modules with high durability and low production cost, which will enable high-power multi-stage cascade modules at a reasonable cost.

High-temperature and high-power-density nanostructured thermoelectric generator for automotive waste heat recovery

International Nuclear Information System (INIS)

Zhang, Yanliang; Cleary, Martin; Wang, Xiaowei; Kempf, Nicholas; Schoensee, Luke; Yang, Jian; Joshi, Giri; Meda, Lakshmikanth

2015-01-01

Highlights: • A thermoelectric generator (TEG) is fabricated using nanostructured half-Heusler materials. • The TE unicouple devices produce superior power density above 5 W/cm"2. • A TEG system with over 1 kW power output is demonstrated by recovering automotive waste heat. - Abstract: Given increasing energy use as well as decreasing fossil fuel sources worldwide, it is no surprise that interest in promoting energy efficiency through waste heat recovery is also increasing. Thermoelectric generators (TEGs) are one of the most promising pathways for waste heat recovery. Despite recent thermoelectric efficiency improvement in nanostructured materials, a variety of challenges have nevertheless resulted in few demonstrations of these materials for large-scale waste heat recovery. Here we demonstrate a high-performance TEG by combining high-efficiency nanostructured bulk materials with a novel direct metal brazing process to increase the device operating temperature. A unicouple device generates a high power density of 5.26 W cm"−"2 with a 500 °C temperature difference between hot and cold sides. A 1 kW TEG system is experimentally demonstrated by recovering the exhaust waste heat from an automotive diesel engine. The TEG system operated with a 2.1% heat-to-electricity efficiency under the average temperature difference of 339 °C between the TEG hot- and cold-side surfaces at a 550 °C exhaust temperature. The high-performance TEG reported here open up opportunities to use TEGs for energy harvesting and power generation applications.

Cost and performance of coal-based energy in Brazil

International Nuclear Information System (INIS)

Temchin, J.; DeLallo, M.R.

1998-01-01

As part of the US Department of Energy's (DOE) efforts to establish the strategic benefits of Clean Coal Technologies (CCT), there is a need to evaluate the specific market potential where coal is a viable option. One such market is Brazil, where significant growth in economic development requires innovative and reliable technologies to support the use of domestic coal. While coal is Brazil's most abundant and economic fossil energy resource, it is presently under utilized in the production of electrical power. This report presents conceptual design for pulverized coal (PC) and circulating fluidized-bed combustion (CFBC) options with resulting capital, operating and financial parameters based on Brazil application conditions. Recent PC and CFBC plant capital costs have dropped with competition in the generation market and have established a competitive position in power generation. Key issues addressed in this study include: Application of market based design approach for FBC and PC, which is competitive within the current domestic, and international power generation markets. Design, fabrication, purchase, and construction methods which reduce capital investment while maintaining equipment quality and plant availability. Impact on coast and performance from application of Brazilian coals, foreign trade and tax policies, construction logistics, and labor requirements. Nominal production values of 200 MWe and 400 MWe were selected for the CFBC power plant and 400 MWe for the PC. The 400 MWe size was chosen to be consistent with the two largest Brazilian PC units. Fluidized bed technology, with limited experience in single units over 200 MW, would consist of two 200 MWe circulating fluidized bed boilers supplying steam to one steam turbine for the 400 MWe capacity. A 200 MWe capacity unit was also developed for CFBC option to support opportunities in re-powering and where specific site or other infrastructure constraints limit production

The role of IGCC technology in power generation using low-rank coal

Energy Technology Data Exchange (ETDEWEB)

Juangjandee, Pipat

2010-09-15

Based on basic test results on the gasification rate of Mae Moh lignite coal. It was found that an IDGCC power plant is the most suitable for Mae Moh lignite. In conclusion, the future of an IDGCC power plant using low-rank coal in Mae Moh mine would hinge on the strictness of future air pollution control regulations including green-house gas emission and the constraint of Thailand's foreign currency reserves needed to import fuels, in addition to economic consideration. If and when it is necessary to overcome these obstacles, IGCC is one variable alternative power generation must consider.

Comparison of electricity production costs of nuclear and coal-fired power plants

International Nuclear Information System (INIS)

Peltzer, M.

1980-01-01

Electricity production costs of nuclear and coal-fired power plants their structure and future development are calculated and compared. Assumed beginning of operation is in the mid-1980. The technical and economical data are based on a nuclear power unit of 1 300 MW and on a coal-fired twin plant of 2 x 750 MW. The study describes and discusses the calculational method and the results. The costs for the electricity generation show an economic advantage for nuclear power. A sensitivity analysis shows that these results are valid also for changed input parameters. (orig.) [de

Fireside corrosion of nickel base alloys in future 700 C coal fired power plants; Rauchgasseitige Korrosion von Nickelbasislegierungen fuer zukuenftige 700 C-Dampfkraftwerke

Energy Technology Data Exchange (ETDEWEB)

Luettschwager, Frank

2011-09-27

Coal is still the most important energy source in Germany. In 2009 it produced 42.9 % of the overall German electrical power. Coal is available world-wide in large quantities and can be delivered economically. One of the possible ways to reduce CO{sub 2} pollution is the increase of efficiency of coal fired power plants, which requires steam conditions of up to 700 C - 730 C and 350 bar. Because many German power units will reach the end of their technical lifespan in a few years or the following decade, one will have the possibility to build up modern types of power plants with increased efficiency of more than 50 %. Some international standards (European Pressure Equipment Directive or ASME Boiler and Pressure Vessel Code) require 100 000 hour creep rupture strength of 100 MPa at 750 C. Therefore, nickel base alloys are in the focus of material qualification processes. Nickel base alloys are well investigated due to their hot corrosion behaviour. It is known that sodium sulphate may generate hot corrosion on those alloys at temperatures above its melting point of 884 C. On nickel base alloys an eutectic mixture of nickel sulphate and sodium sulphate with a melting point of 671 C can be generated, which leads to accelerated corrosion. This work examines, whether the high amount of sulphur and alkali metals will induce hot corrosion at the estimated working temperature on devices manufactured from nickel base alloy. Two synthetic coal ash deposits, according to the chemical composition of hard coal and lignite, and typical flue gases with and without sulphur dioxide were blended of pure agents. The reactions of the deposits with heater tubes' materials and synthetic flue gases are examined in the temperature range from 650 C to 800 C and different time ranges up to 2000 hours. The corroded specimen are examined with SEM/EDX to identify relevant corrosion products and determine the corrosivity of deposited compounds. Deposits increase the corrosion rate of

Environmental impact of coal industry and thermal power plants in India.

Science.gov (United States)

Mishra, U C

2004-01-01

Coal is the only natural resource and fossil fuel available in abundance in India. Consequently, it is used widely as a thermal energy source and also as fuel for thermal power plants producing electricity. India has about 90,000 MW installed capacity for electricity generation, of which more than 70% is produced by coal-based thermal power plants. Hydro-electricity contributes about 25%, and the remaining is mostly from nuclear power plants (NPPs). The problems associated with the use of coal are low calorific value and very high ash content. The ash content is as high as 55-60%, with an average value of about 35-40%. Further, most of the coal is located in the eastern parts of the country and requires transportation over long distances, mostly by trains, which run on diesel. About 70% oil is imported and is a big drain on India's hard currency. In the foreseeable future, there is no other option likely to be available, as the nuclear power programme envisages installing 20,000 MWe by the year 2020, when it will still be around 5% of the installed capacity. Hence, attempts are being made to reduce the adverse environmental and ecological impact of coal-fired power plants. The installed electricity generating capacity has to increase very rapidly (at present around 8-10% per annum), as India has one of the lowest per capita electricity consumptions. Therefore, the problems for the future are formidable from ecological, radio-ecological and pollution viewpoints. A similar situation exists in many developing countries of the region, including the People's Republic of China, where coal is used extensively. The paper highlights some of these problems with the data generated in the author's laboratory and gives a brief description of the solutions being attempted. The extent of global warming in this century will be determined by how developing countries like India manage their energy generation plans. Some of the recommendations have been implemented for new plants

Coal price prospects and availability of coal in the U.K. power generation market

International Nuclear Information System (INIS)

Parker, M.J.

1983-02-01

The availability and cost of National Coal Board coal is discussed with respect to the CEGB's economic case for Sizewell B nuclear power station. It is concluded that an investment which depended for its viability on an early or rapid escalation in international coal prices, or upon this escalation continuing indefinitely into the future, would not be sound. (U.K.)

Comparative analysis of print media coverage of nuclear power and coal issues

International Nuclear Information System (INIS)

Nealey, S.M.; Rankin, W.L.; Montano, D.E.

1978-10-01

Nuclear power has been a more important topic than has coal for the print media, and has received somewhat different treatment. Compared to the number of coal articles, almost twice as many nuclear power articles were printed from 1972 through 1976. Also, while the number of nuclear power articles increased somewhat steadily from 1972 through 1976, the number of coal articles peaked in 1974 and has decreased since. The newspapers sampled gave more prominence to nuclear articles in terms of article type and article location. Also, nuclear articles were more often issue-oriented compared to coal articles. Coal articles were most often about coal mining, labor force concerns, and regulations controls. Nuclear power articles, on the other hand, were mostly about reactor operation. The main issues discussed in the coal articles pertained most to political decisions affecting coal use, to strikes, and to health and safety. The main nuclear issues pertained to economics, to health and safety, and to political decisions. Newspapers handled nuclear power articles in a more polarized manner compared to coal articles which were handled in a more neutral manner. Magazine articles were significantly more antinuclear than anticoal. Some qualifications about these conclusions are included

Proposal for a phase-coherent thermoelectric transistor

International Nuclear Information System (INIS)

Giazotto, F.; Robinson, J. W. A.; Moodera, J. S.; Bergeret, F. S.

2014-01-01

Identifying materials and devices which offer efficient thermoelectric effects at low temperature is a major obstacle for the development of thermal management strategies for low-temperature electronic systems. Superconductors cannot offer a solution since their near perfect electron-hole symmetry leads to a negligible thermoelectric response; however, here we demonstrate theoretically a superconducting thermoelectric transistor which offers unparalleled figures of merit of up to ∼45 and Seebeck coefficients as large as a few mV/K at sub-Kelvin temperatures. The device is also phase-tunable meaning its thermoelectric response for power generation can be precisely controlled with a small magnetic field. Our concept is based on a superconductor-normal metal-superconductor interferometer in which the normal metal weak-link is tunnel coupled to a ferromagnetic insulator and a Zeeman split superconductor. Upon application of an external magnetic flux, the interferometer enables phase-coherent manipulation of thermoelectric properties whilst offering efficiencies which approach the Carnot limit

Proposal for a phase-coherent thermoelectric transistor

Energy Technology Data Exchange (ETDEWEB)

Giazotto, F., E-mail: giazotto@sns.it [NEST, Instituto Nanoscienze-CNR and Scuola Normale Superiore, I-56127 Pisa (Italy); Robinson, J. W. A., E-mail: jjr33@cam.ac.uk [Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS (United Kingdom); Moodera, J. S. [Department of Physics and Francis Bitter Magnet Lab, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Bergeret, F. S., E-mail: sebastian-bergeret@ehu.es [Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, Manuel de Lardizabal 4, E-20018 San Sebastián (Spain); Donostia International Physics Center (DIPC), Manuel de Lardizabal 5, E-20018 San Sebastián (Spain)

2014-08-11

Identifying materials and devices which offer efficient thermoelectric effects at low temperature is a major obstacle for the development of thermal management strategies for low-temperature electronic systems. Superconductors cannot offer a solution since their near perfect electron-hole symmetry leads to a negligible thermoelectric response; however, here we demonstrate theoretically a superconducting thermoelectric transistor which offers unparalleled figures of merit of up to ∼45 and Seebeck coefficients as large as a few mV/K at sub-Kelvin temperatures. The device is also phase-tunable meaning its thermoelectric response for power generation can be precisely controlled with a small magnetic field. Our concept is based on a superconductor-normal metal-superconductor interferometer in which the normal metal weak-link is tunnel coupled to a ferromagnetic insulator and a Zeeman split superconductor. Upon application of an external magnetic flux, the interferometer enables phase-coherent manipulation of thermoelectric properties whilst offering efficiencies which approach the Carnot limit.

Thermoelectric figure of merit of polymeric systems for low-power generators

Science.gov (United States)

Cigarini, Luigi; Ruini, Alice; Catellani, Alessandra; Calzolari, Arrigo

2017-10-01

The request of thermoelectric materials for low-power and flexible applications fosters the investigation of the intrinsic electron and thermal transport of conducting polymeric chains, which are building blocks of the complex variety of organic composites proposed in experimental samples. Using calculations from first principles and the Landauer approach for both electron and phonon carriers, we study the thermoelectric figure of merit zT of three representative and largely used polymer chains, namely poly(3,4-ethylenedioxythiophene), polyaniline and polyfluorene. Our results provide an upper-limit estimate of zT, due to the intrinsic electronic and vibrational properties of the selected compounds, and pave the way to a microscopic understanding of the mechanisms that affect their electronic and transport characteristics in terms of structural distortions and chemical doping.

Advanced pulverized-coal power plants: A U.S. export opportunity

International Nuclear Information System (INIS)

Ruth, L.A.; Ramezan, M.; Izsak, M.S.

1995-01-01

This paper provides an overview of Low Emission Boiler System (LEBS) power generation systems and its potential for generating power worldwide. Based on the fuel availability, power requirements, and environmental regulations, countries have been identified that need to build advanced, clean, efficient, and economical power generation, systems. It is predicted that ''more electrical generation capacity will be built over the next 25 years than was built in the previous century''. For example, China and India alone, with less than 10% of today's demand, plan to build what would amount to a quarter of the world's new capacity. For the near- to mid-term, the LEBS program of Combustion 2000 has the promise to fill some of the needs of the international coal-fired power generation market. The high efficiency of LEBS, coupled with the use of advanced, proven technologies and low emissions, make it a strong candidate for export to those areas whose need for additional power is greatest. LEBS is a highly advanced version of conventional coal-based power plants that have been utilized throughout the world for decades. LEBS employs proven technologies and doesn't require gasification and/or an unconventional combustion environment (e.g., fluidized bed). LEBS is viewed by the utility industry as technically acceptable and commercially feasible

Thermoelectric Generator Power Converter System Configurations: A Review

DEFF Research Database (Denmark)

Man, Elena Anamaria; Schaltz, Erik; Rosendahl, Lasse

2013-01-01

In a Thermoelectric Generator (TEG) system, the Thermoelectric (TE) modules can be connected in series, parallel or a combination of both. Independent of the module connection, the power production of the TEG changes with the temperature gradient applied at its input. In consequence, the system...... tracking (MPPT) technique is widely used for TEG systems. The aim of this paper is to create a survey over the existing state-of-the-art TEG system configurations for TE energy harvesting. Depending on the application specifications, a suitable TEG system topology can be designed with the purpose...

Detailed Modeling and Irreversible Transfer Process Analysis of a Multi-Element Thermoelectric Generator System

Science.gov (United States)

Xiao, Heng; Gou, Xiaolong; Yang, Suwen

2011-05-01

Thermoelectric (TE) power generation technology, due to its several advantages, is becoming a noteworthy research direction. Many researchers conduct their performance analysis and optimization of TE devices and related applications based on the generalized thermoelectric energy balance equations. These generalized TE equations involve the internal irreversibility of Joule heating inside the thermoelectric device and heat leakage through the thermoelectric couple leg. However, it is assumed that the thermoelectric generator (TEG) is thermally isolated from the surroundings except for the heat flows at the cold and hot junctions. Since the thermoelectric generator is a multi-element device in practice, being composed of many fundamental TE couple legs, the effect of heat transfer between the TE couple leg and the ambient environment is not negligible. In this paper, based on basic theories of thermoelectric power generation and thermal science, detailed modeling of a thermoelectric generator taking account of the phenomenon of energy loss from the TE couple leg is reported. The revised generalized thermoelectric energy balance equations considering the effect of heat transfer between the TE couple leg and the ambient environment have been derived. Furthermore, characteristics of a multi-element thermoelectric generator with irreversibility have been investigated on the basis of the new derived TE equations. In the present investigation, second-law-based thermodynamic analysis (exergy analysis) has been applied to the irreversible heat transfer process in particular. It is found that the existence of the irreversible heat convection process causes a large loss of heat exergy in the TEG system, and using thermoelectric generators for low-grade waste heat recovery has promising potential. The results of irreversibility analysis, especially irreversible effects on generator system performance, based on the system model established in detail have guiding significance for

Experimental nuclear thermoelectric assembly open-quotes Gammaclose quotes-a prototype of an unattended self-regulating nuclear thermoelectric station

International Nuclear Information System (INIS)

Buinitskii, B.A.; Kaplar, E.P.; Kondrat'ev, F.V.; Leppik, P.A.; Nafikov, D.Ya.; Pavelko, V.I.; Rychev, A.S.; Tarasov, V.P.; Khlopkin, N.S.

1993-01-01

At the beginning of the seventies, the concept of building small atomic power stations with direct conversion of the thermal energy of a reactor for supplying electricity and heat to consumers located at remote and inaccessible regions was developed on the basis of assessment calculations and technical studies made in the I.V. Kurchatov Institute of Atomic Energy. When new technical solutions were adopted to put this concept into practice, combined trials on a test stand were required. For this purpose, the nuclear thermoelectric test-demonstration assembly open-quotes Gammaclose quotes was built and put into operation in 1981. It is based on the three principles which determine the development of unattended self-regulating nuclear thermoelectric stations: using a water-water reactor with self-regulation of the power as a source of heat; using a cooling system without pumps but with natural circulation of the coolant in the primary and intermediate circuits for removing the hend thermoelectric conversion of heat into electricity. During the ten years of operation of the open-quotes Gammaclose quotes assembly, a research program on the principles of unattended self-regulating nuclear thermoelectric stations was carried out and the results are summarized

Performance analysis of a waste heat recovery thermoelectric generation system for automotive application

International Nuclear Information System (INIS)

Liu, X.; Deng, Y.D.; Li, Z.; Su, C.Q.

2015-01-01

Graphical abstract: A new automotive exhaust-based thermoelectric generator and its “four-TEGs” system are constructed, and the performance characteristics of system are discussed through road test and revolving drum test. - Highlights: • The automotive thermoelectric generator system was constructed and studied. • Road test and revolving drum test were used to measure the output power. • A performance of 201.7 V (open circuit voltage)/944 W obtained. - Abstract: Thermoelectric power generators are one of the promising green energy sources. In this case study, an energy-harvesting system which extracts heat from an automotive exhaust pipe and turns the heat into electricity by using thermoelectric power generators (TEGs) has been constructed. The test bench is developed to analysis the performance of TEG system characteristics, which are undertaken to assess the feasibility of automotive applications. Based on the test bench, a new system called “four-TEGs” system is designed and assembled into prototype vehicle called “Warrior”, through the road test and revolving drum test table, characteristics of the system such as hot-side temperature, cold-side temperature, open circuit voltage and power output are studied, and a maximum power of 944 W was obtained, which completely meets the automotive application. The present study shows the promising potential of using this kind of thermoelectric generator for low-temperature waste heat recovery vehicle

Nominal power density analysis of thermoelectric pins with non-constant cross sections

International Nuclear Information System (INIS)

Shi, Yaoguang; Mei, Deqing; Yao, Zhehe; Wang, Yancheng; Liu, Haiyan; Chen, Zichen

2015-01-01

Highlights: • Nominal power density of TEGs with non-constant cross sections pins is analyzed. • An analytical model of nominal power density (NPD) is developed. • Influences of shape parameter on NPD for different geometric pins are investigated. • Effects of dimensionless efficiency and the temperature ratio on NPD are examined. - Abstract: The investigation of the geometric structure of TEG (thermoelectric generator) pins is essential, as their geometry determines the performance of devices. In this study, nominal power density (NPD) is used to find a better geometric structure of thermoelectric pins of TEGs, since a comparison of maximum dimensionless efficiencies for different geometric pins cannot be used to identify the optimum geometry. The influence of shape parameter on NPD for TEG pins in linear, quadratic and exponential cross-sectional functions is studied. The NPD decreases when the shape parameter increases for different geometric pins, while the maximum values of NPD are the same. Then, the effects of dimensionless efficiency and the temperature ratio on the NPD are analyzed. The NPD decreases with the increase in dimensionless efficiency and temperature ratio. Pins with linear variation in cross section have the highest NPD among the three geometries of pins evaluated

An inductor-based converter with EMI reduction for low-voltage thermoelectric energy harvesting

Science.gov (United States)

Wang, Chuang; Zhao, Kai; Li, Zunchao

2017-07-01

This paper presents a self-powered inductor-based converter which harvests thermoelectric energy and boosts extremely low voltage to a typical voltage level for supplying body sensor nodes. Electromagnetic interference (EMI) of the converter is reduced by spreading spectrum of fundamental frequency and harmonics via pseudo-random modulation, which is obtained via combining the linear feedback shift register and digitally controlled oscillator. Besides, the methods, namely extracting energy near MPP and reducing the power dissipation, are employed to improve the power efficiency. The presented inductor-based converter is designed and verified in CSMC CMOS 0.18-µm 1P6M process. The results reveal that it achieves the high efficiency and EMI reduction at the same time.

Constructing a sustainable power sector in China: current and future emissions of coal-fired power plants from 2010 to 2030

Science.gov (United States)

Tong, D.; Zhang, Q.

2017-12-01

As the largest energy infrastructure in China, power sector consumed more coal than any other sector and threatened air quality and greenhouse gas (GHG) abatement target. In this work, we assessed the evolution of coal-fired power plants in China during 2010-2030 and the evolution of associated emissions for the same period by using a unit-based emission projection model which integrated the historical power plants information, turnover of the future power plant fleet, and the evolution of end-of-pipe control technologies. We found that, driven by the stringent environmental legislation, SO2, NOx, and PM2.5 emissions from China's coal-fired power plants decreased by 49%, 45%, and 24% respectively during 2010-2015, comparing to 14% increase of coal consumption and 15% increase in CO2 emissions. We estimated that under current national energy development planning, coal consumption and CO2 emissions from coal-fired power plants will continue to increase until 2030, in which against the China's Intended Nationally Determined Contributions (INDCs) targets. Early retirement of old and low-efficient power plants will cumulatively reduce 2.2 Pg CO2 emissions from the baseline scenario during 2016-2030, but still could not curb CO2 emissions from the peak before 2030. Owing to the implementation of "near zero" emission control policy, we projected that emissions of air pollutants will significantly decrease during the same period under all scenarios, indicating the decoupling trends of air pollutants and CO2 emissions. Although with limited direct emission reduction benefits, increasing operating hours of power plants could avoid 236 GW of new power plants construction, which could indirectly reduce emissions embodied in the construction activity. Our results identified a more sustainable pathway for China's coal-fired power plants, which could reduce air pollutant emissions, improve the energy efficiency, and slow down the construction of new units. However, continuous

Estimation of environmental external costs between coal fired power plant and nuclear power plant

International Nuclear Information System (INIS)

Moon, G. H.; Kim, S. S.

2000-01-01

First of all, this study evaluated the impacts on the health and the environment of air pollutants emitted from coal power plant and nuclear power pant, two major electric power generating options in Korea. Then, the environmental external costs of those two options were estimated by transforming the health and environment impact into monetary values. To do this, AIRPACTS and Impacts of Atmospheric Release model developed by IAEA were used. The environmental external cost of Samcheonpo coal power plant was estimated about 25 times as much as that of Younggwang nuclear power plant. This result implies that nuclear power plant is a clean technology compared with coal power plant. This study suggests that the external cost should be reflected in the electric system expansion plan in order to allocate energy resources efficiently and to reduce economic impact stemming from the environmental regulation emerged recently on a global level

Development of Self-Powered Wireless-Ready High Temperature Electrochemical Sensors for In-Situ Corrosion Monitoring for Boiler Tubes in Next Generation Coal-based Power Systems

Energy Technology Data Exchange (ETDEWEB)

Liu, Xingbo [West Virginia Univ., Morgantown, WV (United States)

2015-06-30

The key innovation of this project is the synergy of the high temperature sensor technology based on the science of electrochemical measurement and state-of-the-art wireless communication technology. A novel self-powered wireless high temperature electrochemical sensor system has been developed for coal-fired boilers used for power generation. An initial prototype of the in-situ sensor demonstrated the capability of the wireless communication system in the laboratory and in a pilot plant (Industrial USC Boiler Setting) environment to acquire electrochemical potential and current signals during the corrosion process. Uniform and localized under-coal ash deposit corrosion behavior of Inconel 740 superalloy has been studied at different simulated coal ash hot corrosion environments using the developed sensor. Two typical potential noise patterns were found to correlate with the oxidation and sulfidation stages in the hot coal ash corrosion process. Two characteristic current noise patterns indicate the extent of the corrosion. There was a good correlation between the responses of electrochemical test data and the results from corroded surface analysis. Wireless electrochemical potential and current noise signals from a simulated coal ash hot corrosion process were concurrently transmitted and recorded. The results from the performance evaluation of the sensor confirm a high accuracy in the thermodynamic and kinetic response represented by the electrochemical noise and impedance test data.

The future of integrated coal gasification combined cycle power plants

International Nuclear Information System (INIS)

Mueller, R.; Termuehlen, H.

1991-01-01

This paper examines the future of integrated coal gasification combined cycle (IGCC) power plants as affected by various technical, economical and environmental trends in power generation. The topics of the paper include a description of natural gas-fired combined cycle power plants, IGCC plants, coal gasifier concepts, integration of gasifiers into combined cycle power plants, efficiency, environmental impacts, co-products of IGCC power plants, economics of IGCC power plants, and a review of IGCC power plant projects

Effect of Cooling Units on the Performance of an Automotive Exhaust-Based Thermoelectric Generator

Science.gov (United States)

Su, C. Q.; Zhu, D. C.; Deng, Y. D.; Wang, Y. P.; Liu, X.

2017-05-01

Currently, automotive exhaust-based thermoelectric generators (AETEGs) are a hot topic in energy recovery. In order to investigate the influence of coolant flow rate, coolant flow direction and cooling unit arrangement in the AETEG, a thermoelectric generator (TEG) model and a related test bench are constructed. Water cooling is adopted in this study. Due to the non-uniformity of the surface temperature of the heat source, the coolant flow direction would affect the output performance of the TEG. Changing the volumetric flow rate of coolant can increase the output power of multi-modules connected in series or/and parallel as it can improve the temperature uniformity of the cooling unit. Since the temperature uniformity of the cooling unit has a strong influence on the output power, two cooling units are connected in series or parallel to research the effect of cooling unit arrangements on the maximum output power of the TEG. Experimental and theoretical analyses reveal that the net output power is generally higher with cooling units connected in parallel than cooling units connected in series in the cooling system with two cooling units.

ECONOMICS AND FEASIBILITY OF RANKINE CYCLE IMPROVEMENTS FOR COAL FIRED POWER PLANTS

Energy Technology Data Exchange (ETDEWEB)

Richard E. Waryasz; Gregory N. Liljedahl

2004-09-08

ALSTOM Power Inc.'s Power Plant Laboratories (ALSTOM) has teamed with the U.S. Department of Energy National Energy Technology Laboratory (DOE NETL), American Electric Company (AEP) and Parsons Energy and Chemical Group to conduct a comprehensive study evaluating coal fired steam power plants, known as Rankine Cycles, equipped with three different combustion systems: Pulverized Coal (PC), Circulating Fluidized Bed (CFB), and Circulating Moving Bed (CMB{trademark}). Five steam cycles utilizing a wide range of steam conditions were used with these combustion systems. The motivation for this study was to establish through engineering analysis, the most cost-effective performance potential available through improvement in the Rankine Cycle steam conditions and combustion systems while at the same time ensuring that the most stringent emission performance based on CURC (Coal Utilization Research Council) 2010 targets are met: > 98% sulfur removal; < 0.05 lbm/MM-Btu NO{sub x}; < 0.01 lbm/MM-Btu Particulate Matter; and > 90% Hg removal. The final report discusses the results of a coal fired steam power plant project, which is comprised of two parts. The main part of the study is the analysis of ten (10) Greenfield steam power plants employing three different coal combustion technologies: Pulverized Coal (PC), Circulating Fluidized Bed (CFB), and Circulating Moving Bed (CMB{trademark}) integrated with five different steam cycles. The study explores the technical feasibility, thermal performance, environmental performance, and economic viability of ten power plants that could be deployed currently, in the near, intermediate, and long-term time frame. For the five steam cycles, main steam temperatures vary from 1,000 F to 1,292 F and pressures from 2,400 psi to 5,075 psi. Reheat steam temperatures vary from 1,000 F to 1,328 F. The number of feedwater heaters varies from 7 to 9 and the associated feedwater temperature varies from 500 F to 626 F. The main part of the

Externality costs of the coal-fuel cycle: The case of Kusile Power Station

Directory of Open Access Journals (Sweden)

Nonophile P. Nkambule

2017-09-01

Full Text Available Coal-based electricity is an integral part of daily life in South Africa and globally. However, the use of coal for electricity generation carries a heavy cost for social and ecological systems that goes far beyond the price we pay for electricity. We developed a model based on a system dynamics approach for understanding the measurable and quantifiable coal-fuel cycle burdens and externality costs, over the lifespan of a supercritical coal-fired power station that is fitted with a flue-gas desulfurisation device (i.e. Kusile Power Station. The total coal-fuel cycle externality cost on both the environment and humans over Kusile's lifespan was estimated at ZAR1 449.9 billion to ZAR3 279 billion or 91c/kWh to 205c/kWh sent out (baseline: ZAR2 172.7 billion or 136c/kWh. Accounting for the life-cycle burdens and damages of coal-derived electricity conservatively, doubles to quadruples the price of electricity, making renewable energy sources such as wind and solar attractive alternatives. Significance: The use of coal for electricity generation carries a heavy cost for social and ecological systems that goes far beyond the price we pay for electricity. The estimation of social costs is particularly important to the electric sector because of non-differentiation of electricity prices produced from a variety of sources with potentially very dissimilar environmental and human health costs. Because all electricity generation technologies are associated with undesirable side effects in their fuelcycle and lifespan, comprehensive comparative analyses of life-cycle costs of all power generation technologies is indispensable to guide the development of future energy policies in South Africa.

Carbon burnout of pulverised coal in power station furnaces

Energy Technology Data Exchange (ETDEWEB)

R.I. Backreedy; L.M. Fletcher; J.M. Jones; L. Ma; M. Pourkashanian; A. Williams; K. Johnson; D.J. Waldron; P. Stephenson [University of Leeds, Leeds (United Kingdom)

2003-07-01

The degree of carbon burnout in pulverised fuel fired power stations is important because it is linked with power plant efficiency and coal ash suitability for construction purposes. The use of computational methods to calculate carbon burnout in such systems has been aided by the increasing availability of fast computers and improvements in computational methodologies. Despite recent advances in fluid flow, coal devolatilisation and coal combustion models, the use of CFD methods for detailed design purposes or for the selection of commercial coals is still limited. In parallel, industrial engineering codes, which combine simplified thermal models with advanced coal combustion models, are still undergoing development since they provide economic advantages over detailed CFD analysis. Although the major coal combustion processes are well established, an understanding regarding the role of coal macerals and the influence of ash on the combustion process is still lacking. A successful coal model must be able to handle all the complexities of combustion, from the details of the burner geometry through to the formation of unburnt carbon as well as NOx. The development of such a model is described here.

Coal Calorific Value Prediction Based on Projection Pursuit Principle

OpenAIRE

QI Minfang; FU Zhongguang; JING Yuan

2012-01-01

The calorific value of coal is an important factor for the economic operation of coal-fired power plant. However, calorific value is tremendous difference between the different coal, and even if coal is from the same mine. Restricted by the coal market, most of coal fired power plants can not burn the designed-coal by now in China. The properties of coal as received are changing so frequently that pulverized coal firing is always with the unexpected condition. Therefore, the researches on the...

Performance Investigation of an Exhaust Thermoelectric Generator for Military SUV Application

Directory of Open Access Journals (Sweden)

Rui Quan

2018-01-01

Full Text Available To analyze the thermoelectric power generation for sports utility vehicle (SUV application, a novel thermoelectric generator (TEG based on low-temperature Bi2Te3 thermoelectric modules (TEMs and a chaos-shaped brass heat exchanger is constructed. The temperature distribution of the TEG is analyzed based on an experimental setup, and the temperature uniformity optimization method is performed by chipping peak off and filling valley is taken to validate the improved output power. An automobile exhaust thermoelectric generator (AETEG using four TEGs connected thermally in parallel and electrically in series is assembled into a prototype military SUV, its temperature distribution, output voltage, output power, system efficiency, inner resistance, and backpressure is analyzed, and several important influencing factors such as vehicle speed, clamping pressure, engine coolant flow rate, and ambient temperature on its output performance are tested. Experimental results demonstrate that higher vehicle speed, larger clamping pressure, faster engine coolant flow rate and lower ambient temperature can enhance the overall output performance, but the ambient temperature and coolant flow rate are less significant. The maximum output power of AETEG is 646.26 W, the corresponding conversion efficiency is 1.03%, and the increased backpressure changes from 1681 Pa to 1807 Pa when the highest vehicle speed is 125 km/h.

Study of the Radiological Impact of the Coal Fired Power Plants on the Environment. The As Pontes coal-fired Power Plant

International Nuclear Information System (INIS)

Cancio, D.; Robles, B.; Mora, J. C.

2009-01-01

As part of the Study carried out to determine the radiological impact of the four main Spanish coal-fired power plants, the Study on the As Pontes Coal-Fired Coal Power Plant was finalized. In the Report containing the study are included every measurement performed, as well as the modelling and evaluations carried out in order to assess the radiological impact. The general conclusion obtained is that under a radiological point of view, the impact of this installation on the public and the environment is very small. Also the radiological impact on the workers of the installation was assessed, obtaining too very small increases over the natural background. (Author) 61 refs.

High Thermoelectric Power Factor of High-Mobility 2D Electron Gas.

Science.gov (United States)

Ohta, Hiromichi; Kim, Sung Wng; Kaneki, Shota; Yamamoto, Atsushi; Hashizume, Tamotsu

2018-01-01

Thermoelectric conversion is an energy harvesting technology that directly converts waste heat from various sources into electricity by the Seebeck effect of thermoelectric materials with a large thermopower ( S ), high electrical conductivity (σ), and low thermal conductivity (κ). State-of-the-art nanostructuring techniques that significantly reduce κ have realized high-performance thermoelectric materials with a figure of merit ( ZT = S 2 ∙σ∙ T ∙κ -1 ) between 1.5 and 2. Although the power factor (PF = S 2 ∙σ) must also be enhanced to further improve ZT , the maximum PF remains near 1.5-4 mW m -1 K -2 due to the well-known trade-off relationship between S and σ. At a maximized PF, σ is much lower than the ideal value since impurity doping suppresses the carrier mobility. A metal-oxide-semiconductor high electron mobility transistor (MOS-HEMT) structure on an AlGaN/GaN heterostructure is prepared. Applying a gate electric field to the MOS-HEMT simultaneously modulates S and σ of the high-mobility electron gas from -490 µV K -1 and ≈10 -1 S cm -1 to -90 µV K -1 and ≈10 4 S cm -1 , while maintaining a high carrier mobility (≈1500 cm 2 V -1 s -1 ). The maximized PF of the high-mobility electron gas is ≈9 mW m -1 K -2 , which is a two- to sixfold increase compared to state-of-the-art practical thermoelectric materials.

Characterization of a thermoelectric cooler based thermal management system under different operating conditions

International Nuclear Information System (INIS)

Russel, M.K.; Ewing, D.; Ching, C.Y.

2013-01-01

The performance of a thermoelectric cooler (TEC) based thermal management system for an electronic packaging design that operates under a range of ambient conditions and system loads is examined using a standard model for the TEC and a thermal resistance network for the other components. Experiments were performed and it was found that the model predictions were in good agreement with the experimental results. An operating envelope is developed to characterize the TEC based thermal management system for peak and off peak operating conditions. Parametric studies were performed to analyze the effect of the number of TEC module(s) in the system, geometric factor of the thermo-elements and the cold to hot side thermal resistances on the system performance. The results showed that there is a tradeoff between the extent of off peak heat fluxes and ambient temperatures when the system can be operated at a low power penalty region and the maximum capacity of the system. - Highlights: ► A model was developed for thermal management systems using thermoelectric coolers. ► Model predictions were in good agreement with experimental results. ► An operating envelope was developed for peak and off peak conditions. ► The effect of the number of thermoelectric coolers on the system was determined.

Beneficiation of power grade coals: its relevance to future coal use in India

International Nuclear Information System (INIS)

Sachdev, R.K.

1992-01-01

With consumption increasing from the current level of 220 mt. to over 600 mt. by the year 2010 A.D., coal will continue to enjoy a prime position in the overall energy scene in India. India being endowed with coal resources of high ash content, the major coal consuming industries have, by and large, adjusted the combustion techniques to suit the quality of coal available. However, wide fluctuations in the quality of coal supplies adversely affect their plant performance. With the coal deposits being localised in the eastern and central parts of peninsular India, the load on railway network in carrying coal to other parts of the country will continue to increase and this will emerge as a major constraint in managing the coal supply to the consuming centres located away from the coal fields. It is in this context, the author has discussed the need of setting up of coal cleaning facilities at the pit heads. The extent to which the transport network will be relieved of carrying avoidable muck in coal has been quantified along with the benefits that will accrue in the form of extra transport capacity, better power plant performance and reduced air pollution and solid waste at consumer end. (author). 5 refs., 6 tabs., 8 figs

Thermoelectric cooling container for medical applications

Energy Technology Data Exchange (ETDEWEB)

Aivazov, A A; Shtern, Y I; Budaguan, B G; Makhrachev, K B; Pastor, M

1997-07-01

In this work the thermoelectric cooling container for storing and transportation of the medicine, particularly for insulin, is discussed. In the working volume the temperature is supported on the level of +4 C. The container can work in two operating conditions: with the power supply and without the power supply. Two removable blocks are used for this purpose. One block (thermoelectric) is used for the work with the power supply and another (passive)-for the work without power supply. The thermoelectric block has a 12V power supply, which is used in the automobiles, yachts and other kinds of transport. The temperature in the working volume is supported by the use of the Peltier effect. An electronic device is used in this block and stabilizes temperature on the level of +4 C and indicates information about working conditions. The thermoelectric container has a power supply block for work at 220(110)V. The working temperature in the container can be maintained in the absence of the power supply. In this case the necessary temperature conditions are supported by melting of the crystallized salt. For this purpose the container has a hermetic volume containing this salt and contacting with the working volume.

Implementation of thermoelectric module for cooling process of microscale experimental room

Science.gov (United States)

Gołebiowska, Justyna; Żelazna, Agnieszka; Zioło, Paweł

2017-08-01

Thermoelectric modules, also known as Peltier modules, are used for cooling small devices and also, according to literature, in refrigeration. They can be an alternative to conventional refrigeration systems based on the use of compressors chillers powered by AC power. Peltier modules are powered by direct current (DC), which allows to power them directly supply by photovoltaic modules. In this paper operation of thermoelectric module used for cooling experimental room of cubature 0.125 m3 is presented. The study involves investigation of temperatures achieved on the cold and hot sides of module and inside the experimental room depending on the values of module supplying current. These studies provide an introduction to the assessment of the influence of different methods of heat removal on the hot side of thermoelectric module on cooling efficiency of whole system.

Effects of Channel Geometry and Coolant Fluid on Thermoelectric Net Power

DEFF Research Database (Denmark)

Rezaniakolaei, Alireza; Rosendahl, Lasse; Sørensen, Kim

2014-01-01

Channel geometry has a strong influence on the heat transfer coefficient and cooling energy input in a heat sink. The net power output in a thermoelectric generator (TEG) can be defined as power generation minus the required cooling energy in TEG. This study aims to evaluate the net power generat......, and the maximum net power output occurs at smaller Reynolds number when the channel hydraulic diameter reduces....... generation in TEG for different size of hydraulic diameter of plate-fin heat sink and over a wide range of Reynolds number. The particular focus of this study is to find optimal Reynolds number in each considered channel hydraulic diameter and to explore optimal channel hydraulic diameter for maximum TEG net...

The economics of coal and nuclear power plants

International Nuclear Information System (INIS)

Prior, M.J.

1978-01-01

This paper is largely based on a comparison of electrical generating costs from coal-fired power plants and thermal nuclear reactors. Following an introductory section, the subject is considered under the following headings: methodology; cost basis (capital costs, fuel costs, plant factors); generating costs; the fast breeder reactor -general issues; the economics of fast breeder reactors; conclusions and questions. (U.K.)

International coal and the future of nuclear power in the UK

International Nuclear Information System (INIS)

Parker, M.J.

1987-01-01

The future international price of coal is a central issue in the economic comparison of coal-fired and nuclear power stations. However, this is very difficult to estimate as prices are uncertain and subject to wide margins of error. Recent trends are discussed. The increase in the seaborne steam coal trade is one trend. Although only about 5% of steam coal is traded, this is mainly in the Far East and in Western Europe. It is steam coal prices which are relevant in considering nuclear economies. The structure of the international steam coal market is explained. An assessment of future prices of steam coal considers both demand and supply. The delivered cost of steam coal to N.W. Europe in 1986 is shown - the main suppliers being Australia, Colombia, South Africa and the USA. China and Poland are also exporters of steam coal. Currently, there is an over-supply which is keeping the price low. However, as demand increases prices are likely to rise in the 1990s but with upper limits depending on the total volume of trade. Thirteen graphs or maps illustrate the figures on which the discussion and conclusions are based. (UK)

Solid State Microchp Based On Thermophotovoltaic And Thermoelectric Conversion

OpenAIRE

Worek, William M.; Brown, Christopher; Trojanowski, Rebecca; Butcher, Thomas; Horne, Edward

2012-01-01

MicroCHP involves the coproduction of both heat and electric power in (typically) residential heating systems. A range of different energy conversion technologies are currently receiving attention for this application including Stirling engines, internal combustion engines, fuel cells, and Rankine cycles with steam or organic compounds as working fluids. In this work the use of ThermoPhotoVoltaic (TPV) and ThermoElectric (TE) conversion devices either alone or in combination for power product...

Atmospheric emissions of F, As, Se, Hg, and Sb from coal-fired power and heat generation in China.

Science.gov (United States)

Chen, Jian; Liu, Guijian; Kang, Yu; Wu, Bin; Sun, Ruoyu; Zhou, Chuncai; Wu, Dun

2013-02-01

Coal is one of the major energy resources in China, with nearly half of produced Chinese coal used for power and heat generation. The large use of coal for power and heat generation in China may result in significant atmospheric emissions of toxic volatile trace elements (i.e. F, As, Se, Hg, and Sb). For the purpose of estimating the atmospheric emissions from coal-fired power and heat generation in China, a simple method based on coal consumption, concentration and emission factor of trace element was adopted to calculate the gaseous emissions of elements F, As, Se, Hg, and Sb. Results indicate that about 162161, 236, 637, 172, and 33 t F, As, Se, Hg, and Sb, respectively, were introduced into atmosphere from coal combustion by power and heat generation in China in 2009. The atmospheric emissions of F, As, Se, Hg, and Sb by power and heat generation increased from 2005 to 2009 with increasing coal consumptions. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

The Increase of Power Efficiency of Underground Coal Mining by the Forecasting of Electric Power Consumption

Science.gov (United States)

Efremenko, Vladimir; Belyaevsky, Roman; Skrebneva, Evgeniya

2017-11-01

In article the analysis of electric power consumption and problems of power saving on coal mines are considered. Nowadays the share of conditionally constant costs of electric power for providing safe working conditions underground on coal mines is big. Therefore, the power efficiency of underground coal mining depends on electric power expense of the main technological processes and size of conditionally constant costs. The important direction of increase of power efficiency of coal mining is forecasting of a power consumption and monitoring of electric power expense. One of the main approaches to reducing of electric power costs is increase in accuracy of the enterprise demand in the wholesale electric power market. It is offered to use artificial neural networks to forecasting of day-ahead power consumption with hourly breakdown. At the same time use of neural and indistinct (hybrid) systems on the principles of fuzzy logic, neural networks and genetic algorithms is more preferable. This model allows to do exact short-term forecasts at a small array of input data. A set of the input parameters characterizing mining-and-geological and technological features of the enterprise is offered.

Hydrogen Fuel as Ecological Contribution to Operation of the Existing Coal-Fired Thermal Power Plants

International Nuclear Information System (INIS)

Cosic, D.

2009-01-01

The analysis is carried out of the application of a new hydrogen based alternative fuel as ecological contribution of the coal thermal power plants operation. Given the fact that coal thermal power plants are seen as the largest producers, not only of CO 2 , but of all others harmful gases, the idea is initiated to use the new alternative fuel as an additive to the coal which would result in much better performance of the coal power plants from an ecological point of view. It is possible to use such a fuel in relation of 10-30% of former coal use. The positive influence of such an application is much bigger than relative used quantity. This lecture has a goal to incite potential investors to create conditions for industrial testing of the new fuel. It will be very interesting to animate investors for large-scale production of the new fuel, too.(author).

Test System for Thermoelectric Modules and Materials

Science.gov (United States)

Hejtmánek, J.; Knížek, K.; Švejda, V.; Horna, P.; Sikora, M.

2014-10-01

We present a design for a complex measuring device that enables its user to assess the parameters of power-generating thermoelectric modules (TEMs) (or bulk thermoelectric materials) under a wide range of temperatures ( T cold = 25°C to 90°C, T hot TEM, the actual heat flow through the module, and its mechanical load, which can be varied during the measurement. Key components of our testing setup are (i) a measuring chamber where the TEM/material is compressed between thermally shielded heating blocks equipped with a mechanical loading system and water-cooled copper-based cooler, (ii) an electrical load system, (iii) a type K thermocouple array connected to a data acquisition computer, and (iv) a thermostatic water-based cooling system with electronically controlled flow rate and temperature of cooling water. Our testing setup represents a useful tool able to assess, e.g., the thermoelectric parameters of newly developed TEMs and materials or to evaluate the thermoelectric parameters of commercially available modules and materials for comparison with values declared by the manufacturer.

Modelling of thermoelectric materials

DEFF Research Database (Denmark)

Bjerg, Lasse

In order to discover new good thermoelectric materials, there are essentially two ways. One way is to go to the laboratory, synthesise a new material, and measure the thermoelectric properties. The amount of compounds, which can be investigated this way is limited because the process is time...... consuming. Another approach is to model the thermoelectric properties of a material on a computer. Several crystal structures can be investigated this way without use of much man power. I have chosen the latter approach. Using density functional theory I am able to calculate the band structure of a material....... This band structure I can then use to calculate the thermoelectric properties of the material. With these results I have investigated several materials and found the optimum theoretical doping concentration. If materials with these doping concentrations be synthesised, considerably better thermoelectric...

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.

Survey of radionuclide emissions from coal-fired power plants and examination of impacts from a proposed circulating fluidized bed boiler power plant

International Nuclear Information System (INIS)

Steiner, C.P.; Militana, L.M.; Harvey, K.A.; Kinsey, G.D.

1995-01-01

This paper presents the results of a literature survey that examined radionuclide emissions from coal-fired power plants. Literature references from both the US and foreign countries are presented. Emphasis is placed on references from the US because the radionuclide emissions from coal-fired power plants are related to radionuclide concentrations in the coal, which vary widely throughout the world. The radionuclides were identified and quantified for various existing power plants reported in the literature. Applicable radionuclide emissions criteria discovered in the literature search were then applied to a proposed circulating fluidized bed boiler power plant. Based upon the derived radionuclide emission rates applied to the proposed power plant, an air quality modeling analysis was performed. The estimated ambient concentrations were compared to the most relevant existing regulatory ambient levels for radionuclides

Committed CO2 Emissions of China's Coal-fired Power Plants

Science.gov (United States)

Suqin, J.

2016-12-01

The extent of global warming is determined by the cumulative effects of CO2 in the atmosphere. Coal-fired power plants, the largest anthropogenic source of CO2 emissions, produce large amount of CO2 emissions during their lifetimes of operation (committed emissions), which thus influence the future carbon emission space under specific targets on mitigating climate change (e.g., the 2 degree warming limit relative to pre-industrial levels). Comprehensive understanding of committed CO2 emissions for coal-fired power generators is urgently needed in mitigating global climate change, especially in China, the largest global CO2emitter. We calculated China's committed CO2 emissions from coal-fired power generators installed during 1993-2013 and evaluated their impact on future emission spaces at the provincial level, by using local specific data on the newly installed capacities. The committed CO2 emissions are calculated as the product of the annual coal consumption from newly installed capacities, emission factors (CO2emissions per unit crude coal consumption) and expected lifetimes. The sensitivities about generators lifetimes and the drivers on provincial committed emissions are also analyzed. Our results show that these relatively recently installed coal-fired power generators will lead to 106 Gt of CO2 emissions over the course of their lifetimes, which is more than three times the global CO2 emissions from fossil fuels in 2010. More than 80% (85 Gt) of their total committed CO2 will be emitted after 2013, which are referred to as the remaining emissions. Due to the uncertainties of generators lifetime, these remaining emissions would increase by 45 Gt if the lifetimes of China's coal-fired power generators were prolonged by 15 years. Furthermore, the remaining emissions are very different among various provinces owing to local developments and policy disparities. Provinces with large amounts of secondary industry and abundant coal reserves have higher committed

The Mesaba Energy Project: Clean Coal Power Initiative, Round 2

Energy Technology Data Exchange (ETDEWEB)

Stone, Richard; Gray, Gordon; Evans, Robert

2014-07-31

The Mesaba Energy Project is a nominal 600 MW integrated gasification combine cycle power project located in Northeastern Minnesota. It was selected to receive financial assistance pursuant to code of federal regulations (?CFR?) 10 CFR 600 through a competitive solicitation under Round 2 of the Department of Energy?s Clean Coal Power Initiative, which had two stated goals: (1) to demonstrate advanced coal-based technologies that can be commercialized at electric utility scale, and (2) to accelerate the likelihood of deploying demonstrated technologies for widespread commercial use in the electric power sector. The Project was selected in 2004 to receive a total of $36 million. The DOE portion that was equally cost shared in Budget Period 1 amounted to about $22.5 million. Budget Period 1 activities focused on the Project Definition Phase and included: project development, preliminary engineering, environmental permitting, regulatory approvals and financing to reach financial close and start of construction. The Project is based on ConocoPhillips? E-Gas? Technology and is designed to be fuel flexible with the ability to process sub-bituminous coal, a blend of sub-bituminous coal and petroleum coke and Illinois # 6 bituminous coal. Major objectives include the establishment of a reference plant design for Integrated Gasification Combined Cycle (?IGCC?) technology featuring advanced full slurry quench, multiple train gasification, integration of the air separation unit, and the demonstration of 90% operational availability and improved thermal efficiency relative to previous demonstration projects. In addition, the Project would demonstrate substantial environmental benefits, as compared with conventional technology, through dramatically lower emissions of sulfur dioxide, nitrogen oxides, volatile organic compounds, carbon monoxide, particulate matter and mercury. Major milestones achieved in support of fulfilling the above goals include obtaining Site, High Voltage

Economic Decision-Making for Coal Power Flexibility Retrofitting and Compensation in China

Directory of Open Access Journals (Sweden)

Chunning Na

2018-01-01

Full Text Available In China, in order to integrate more renewable energy into the power grid, coal power flexibility retrofitting is imperative. This paper elaborates a generic method for estimating the flexibility potential from the rapid ramp rate and peak shaving operation using nonlinear programming, and defines three flexibility elastic coefficients to quantify the retrofitted targets. The optimized range of the retrofitted targets determined by the flexibility elastic coefficients have a reference significance on coal power flexibility retrofitting. Then, in order to enable economic decisions for coal power flexibility retrofitting, we address a profit maximizing issue regarding optimization decisions for coal power flexibility retrofitting under an assumption of perfect competition, further analyzing the characteristic roots of marginal cost equal to marginal revenue. The rationality of current compensation standards for peak shaving in China can also be judged in the analysis. The case study results show that economic decision-making depends on the compensation standard and the peak shaving depth and time. At a certain peak shaving depth and time, with rational compensation standard power plants are willing to carry out coal power flexibility retrofitting. The current compensation standard in Northeast China is high enough to carry out coal power flexibility retrofitting. These research conclusions have theoretical significance for China’s peak shaving compensation standards formulation.

Pollution control technologies applied to coal-fired power plant operation

Directory of Open Access Journals (Sweden)

Maciej Rozpondek

2009-09-01

Full Text Available Burning of fossil fuels is the major source of energy in today's global economy with over one-third of the world's powergeneration derived from coal combustion. Although coal has been a reliable, abundant, and relatively inexpensive fuel source for mostof the 20th century, its future in electric power generation is under increasing pressure as environmental regulations become morestringent worldwide. Current pollution control technologies for combustion exhaust gas generally treat the release of regulatedpollutants: sulfur dioxide, nitrogen oxides and particulate matter as three separate problems instead of as parts of one problem. Newand improved technologies have greatly reduced the emissions produced per ton of burning coal. The term “Clean Coal CombustionTechnology” applies generically to a range of technologies designed to greatly reduce the emissions from coal-fired power plants.The wet methods of desulfurization at present are the widest applied technology in professional energetics. This method is economicand gives good final results but a future for clean technologies is the biomass. Power from biomass is a proven commercial optionof the electricity generation in the World. An increasing number of power marketers are starting to offer environmentally friendlyelectricity, including biomass power, in response to the consumer demand and regulatory requirements.

Comprehensive Report to Congress Clean Coal Technology Program: Clean power from integrated coal/ore reduction

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-10-01

This report describes a clean coal program in which an iron making technology is paired with combined cycle power generation to produce 3300 tons per day of hot metal and 195 MWe of electricity. The COREX technology consists of a metal-pyrolyzer connected to a reduction shaft, in which the reducing gas comes directly from coal pyrolysis. The offgas is utilized to fuel a combined cycle power plant.

Alternative Green Technology for Power Generation Using Waste-Heat Energy And Advanced Thermoelectric Materials, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — NASA is interested in advancing green technology research for achieving sustainable and environmentally friendly energy sources. Thermo-electric power generation...

Micro/Nano Fabricated Solid-State Thermoelectric Generator Devices for Integrated High Voltage Power Sources

Science.gov (United States)

Fleurial, J.-P.; Ryan, M. A.; Snyder, G. J.; Huang, C.-K.; Whitacre, J. F.; Patel, J.; Lim, J.; Borshchevsky, A.

2002-01-01

Deep space missions have a strong need for compact, high power density, reliable and long life electrical power generation and storage under extreme temperature conditions. Except for electrochemical batteries and solar cells, there are currently no available miniaturized power sources. Conventional power generators devices become inefficient in extreme environments (such as encountered in Mars, Venus or outer planet missions) and rechargeable energy storage devices can only be operated in a narrow temperature range thereby limiting mission duration. The planned development of much smaller spacecrafts incorporating a variety of micro/nanodevices and miniature vehicles will require novel, reliable power technologies. It is also expected that such micro power sources could have a wide range of terrestrial applications, in particular when the limited lifetime and environmental limitations of batteries are key factors. Advanced solid-state thermoelectric combined with radioisotope or waste heat sources and low profile energy storage devices are ideally suited for these applications. The Jet Propulsion Laboratory has been actively pursuing the development of thermoelectric micro/nanodevices that can be fabricated using a combination of electrochemical deposition and integrated circuit processing techniques. Some of the technical challenges associated with these micro/nanodevice concepts, their expected level of performance and experimental fabrication and testing results to date are presented and discussed.

Thermoelectric power of the Ni and Cd substituted YBCO system

International Nuclear Information System (INIS)

Mukherjee, C.D.; Ranganathan, R.; Raychaudhuri, A.K.; Chatterjee, N.

1989-01-01

The thermoelectric power behaviour in the range between 250 K and the superconducting transition temperature T c of YBa 2 Cu 3-x A x O 7-y (where A = Ni or Cd and x = 0.2 and 0.4) samples has been examined. The normalized resistance and thermopower of substituted samples as functions of temperature are plotted and discussed. It was concluded that nickel has a slight positive role in causing overall thermopower generation in the YBCO system

Coal-fired power plants and the causes of high temperature corrosion

Energy Technology Data Exchange (ETDEWEB)

Oakey, J E; Simms, N J [British Coal Corporation, Coal Technology Development Div., Cheltenham, Glos (United Kingdom); Tomkings, A B [ERA Technology Ltd., Leatherhead, Surrey (United Kingdom)

1996-12-01

The heat exchangers in all types of coal-fired power plant operate in aggressive, high temperature environments where high temperature corrosion can severely limit their service lives. The extent of this corrosion is governed by the combined effects of the operating conditions of the heat exchanger and the presence of corrosive species released from the coal during operation. This paper reviews the coal-related factors, such as ash deposition, which influence the operating environments of heat exchangers in three types of coal-fired power plant - conventional pulverized coal boilers, fluidized bed boilers and coal gasification systems. The effects on the performance of the materials used for these heat exchangers are then compared. (au) 35 refs.

Ways to Improve Russian Coal-Fired Power Plants

International Nuclear Information System (INIS)

Tumanovskii, A. G.; Olkhovsky, G. G.

2015-01-01

Coal is an important fuel for the electric power industry of Russia, especially in Ural and the eastern part of the country. It is fired in boilers of large (200 – 800 MW) condensing power units and in many cogeneration power plants with units rated at 50 – 180 MW. Many coal-fired power plants have been operated for more than 40 – 50 years. Though serviceable, their equipment is obsolete and does not comply with the current efficiency, environmental, staffing, and availability standards. It is urgent to retrofit and upgrade such power plants using advanced equipment, engineering and business ideas. Russian power-plant engineering companies have designed such advanced power units and their equipment such as boilers, turbines, auxiliaries, process and environmental control systems similar to those produced by the world’s leading manufacturers. Their performance and ways of implementation are discussed

Ways to Improve Russian Coal-Fired Power Plants

Energy Technology Data Exchange (ETDEWEB)

Tumanovskii, A. G., E-mail: vti@vti.ru; Olkhovsky, G. G. [JSC “All-Russia Thermal Engineering Institute,” (Russian Federation)

2015-07-15

Coal is an important fuel for the electric power industry of Russia, especially in Ural and the eastern part of the country. It is fired in boilers of large (200 – 800 MW) condensing power units and in many cogeneration power plants with units rated at 50 – 180 MW. Many coal-fired power plants have been operated for more than 40 – 50 years. Though serviceable, their equipment is obsolete and does not comply with the current efficiency, environmental, staffing, and availability standards. It is urgent to retrofit and upgrade such power plants using advanced equipment, engineering and business ideas. Russian power-plant engineering companies have designed such advanced power units and their equipment such as boilers, turbines, auxiliaries, process and environmental control systems similar to those produced by the world’s leading manufacturers. Their performance and ways of implementation are discussed.

Dynamic simulation model of a coal thermoelectric plant with a flue gas desulphurisation system

International Nuclear Information System (INIS)

Caselles-Moncho, Antonio; Ferrandiz-Serrano, Liliana; Peris-Mora, Eduardo

2006-01-01

In this paper a Dynamic Simulation Model has been used to present the likely responses of the electricity industries' latest perturbations such as: changes in environmental regulations, international fuel market evolution, restriction on fuel supply and increase on fuel prices, liberalisation of the European Electricity Market, and the results of applying energy policies and official tools such as taxes and emission allowances. The case under study refers to the Teruel Power Plant, built after the 1970s oil crisis to ensure national electricity supply; burning domestically produced coal in order to ensure local mining activity. The Teruel Power Plant has made relevant investments in order to meet emission limits, such as a Flue Gas Desulphurisation Plant. The economic viability of the power stations has to be analysed after environmental costs have been internalised. A system is defined that studies the coal-firing Electric Power Plant selling energy to the free electricity market, whenever the generation cost is competitive. A Dynamic Simulation Model would appear to be an accurate tool to optimise power station management within different frameworks

Effect of Mach number on thermoelectric performance of SiC ceramics nose-tip for supersonic vehicles

International Nuclear Information System (INIS)

Han, Xiao-Yi; Wang, Jun

2014-01-01

This paper focus on the effects of Mach number on thermoelectric energy conversion for the limitation of aero-heating and the feasibility of energy harvesting on supersonic vehicles. A model of nose-tip structure constructed with SiC ceramics is developed to numerically study the thermoelectric performance in a supersonic flow field by employing the computational fluid dynamics and the thermal conduction theory. Results are given in the cases of different Mach numbers. Moreover, the thermoelectric performance in each case is predicted with and without Thomson heat, respectively. Due to the increase of Mach number, both the temperature difference and the conductive heat flux between the hot side and the cold side of nose tip are increased. This results in the growth of the thermoelectric power generated and the energy conversion efficiency. With respect to the Thomson effect, over 50% of total power generated converts to Thomson heat, which greatly reduces the thermoelectric power and efficiency. However, whether the Thomson effect is considered or not, with the Mach number increasing from 2.5 to 4.5, the thermoelectric performance can be effectively improved. -- Highlights: • Thermoelectric SiC nose-tip structure for aerodynamic heat harvesting of high-speed vehicles is studied. • Thermoelectric performance is predicted based on numerical methods and experimental thermoelectric parameters. • The effects of Mach number on thermoelectric performance are studied in the present paper. • Results with respect to the Thomson effect are also explored. • Output power and energy efficiency of the thermoelectric nose-tip are increased with the increase of Mach number

Techno-Economic Analysis of Integration of Low-Temperature Geothermal Resources for Coal-Fired Power Plants

Energy Technology Data Exchange (ETDEWEB)

Bearden, Mark D.; Davidson, Casie L.; Horner, Jacob A.; Heldebrant, David J.; Freeman, Charles J.

2016-05-11

Presented here are the results of a techno-economic (TEA) study of the potential for coupling low-grade geothermal resources to boost the electrical output from coal-fired power plants. This study includes identification of candidate 500 MW subcritical coal-fired power plants in the continental United States, followed by down-selection and characterization of the North Valmy generating station, a Nevada coal-fired plant. Based on site and plant characteristics, ASPEN Plus models were designed to evaluate options to integrate geothermal resources directly into existing processes at North Valmy. Energy outputs and capital costing are presented for numerous hybrid strategies, including integration with Organic Rankine Cycles (ORCs), which currently represent the primary technology for baseload geothermal power generation.

Chances of coal in European power industry

Science.gov (United States)

Łukaszczyk, Zygmunt; Badura, Henryk

2017-11-01

Poland's accession to the European Union has reduced the remnants of import barriers. Moreover, the consolidation and commercialization of the energy sector, the implementation of climate package elements and a whole host of other determinants have caused hard coal mining to begin functioning in a highly competitive market, and its negotiating position, as well as the possibility of survival, depends not only on the level of coal prices in international markets, but also on internal competition. This paper discusses the position of power coal on international markets and presents some current problems concerning the functioning of particular segments of the hard coal market in the European Union and Poland in terms of opportunities and threats that are a result of climate and energy policy.

Update on the modernization of 200 MW hard coal power plants in Poland

International Nuclear Information System (INIS)

Szabo, T.E.; Kopec, M.

1993-01-01

In June 1990, the Coalition of 200 MW, Hard Coal, Polish Power Plants representing an installed base of 10,240 MW, including 45 units of 200 MW, signed an agreement with the Westinghouse Electric Corporation, Power Generation Business Unit, based in Orlando, Florida, to cooperate on developing a modernization program for the 200 MW units. Program funding was obtained with The United States Trade Development Program (TDP) providing approximately 2/3 of the cost, and the balance provided by Westinghouse. On March 5, 1992, the Polish-American (51% Westinghouse, 49% Seven (7) Hard Coal Power Plants), Joint Venture Company, MODELPOL, Ltd. (Polish acronym for 'MODernizacja ELektrowni POLskich' or Modernization of Polish Power Plants) was established with the goal to implement not only technically but financially the recommendations of the Modernization Study. The mission given MODELPOL, Ltd. by their Polish-American Shareholders was to: develop the specific modernization programs for each hard coal power plant; assist in identifying and obtaining the financial resources required for implementation; and provide technological preventative maintenance services to improve unit availability. Within these aims was the target to reduce SO 2 , and particulate emissions. The first program is taking place at the Laziska Power Plant, followed by Rybnik. Further projects are in the planning stages. Finance is a constant problem, this should be eased by the restructuring of the power industry. Future programmes include connection to the European Community Power Grid. 5 figs