Sample records for thermal power generated

  1. Solar thermal power generation

    Microsoft Academic Search

    W. P. Teagan; S. Atallah; P. E. Glaser

    1976-01-01

    This paper discusses the preliminary design and feasibility analysis of a 100-kW electric generation station utilizing solar energy. The primary components of the system are an advanced flat-plate solar collector array and a Rankine-cycle engine which utilizes an organic fluid. Preliminary estimates for the cost of power generated by the proposed facility lies between 3.9 and 6.8 cents\\/kWhr. A marked

  2. MultiUse solar thermal power generators

    Microsoft Academic Search

    Russell Abbott

    2001-01-01

    This paper describes Ontario Engineering International, Inc. (OEI) approach to a solar thermal power generation system using a number of thermal power generation technologies for possible applications to Mars exploration, material processing and for power generation on Earth. The latest power stage and generator design presented here were the culmination of studies covering a wide variety of generator configurations and

  3. Solar thermal aided power generation

    Microsoft Academic Search

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

    2010-01-01

    Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature.

  4. Thermal energy storage considerations for solar-thermal power generation

    Microsoft Academic Search

    N. Lior; P. S. Ayyaswamy; J. Oleary; K. W. Kauffman; H. Yeh; H. G. Lorsch

    1976-01-01

    The problem of thermal energy storage for solar-thermal power generation is examined. Major conceptual systems for thermal storage are proposed and described. Storage modes through sensible heat, latent heat (phase change), and thermochemical energy are reviewed and proposed. A survey of applicable materials for thermal storage, which includes available thermophysical properties, compatibility with containing and heat transfer interfaces, and economics,

  5. Phase Change Material Thermal Power Generator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    2013-01-01

    An innovative modification has been made to a previously patented design for the Phase Change Material (PCM) Thermal Generator, which works in water where ocean temperature alternatively melts wax in canisters, or allows the wax to re-solidify, causing high-pressure oil to flow through a hydraulic generator, thus creating electricity to charge a battery that powers the vehicle. In this modification, a similar thermal PCM device has been created that is heated and cooled by the air and solar radiation instead of using ocean temperature differences to change the PCM from solid to liquid. This innovation allows the device to use thermal energy to generate electricity on land, instead of just in the ocean.

  6. Solar thermal photovoltaic electric power generator

    Microsoft Academic Search

    W. E. Horne

    1978-01-01

    The paper considers the concept of a solar thermal photovoltaic generator which, theoretically, could reach efficiencies of the order of 70%. The concept consists of a solar concentrator which focuses solar energy onto an absorber heated to incandescent temperatures (2500-3000 K). The radiation emitted from the incandescent source has a peak energy spectrum that closely matches the band energy of

  7. Simulation of a pilot solar chimney thermal power generating equipment

    Microsoft Academic Search

    Xinping Zhou; Jiakuan Yang; Bo Xiao; Guoxiang Hou

    2007-01-01

    A pilot experimental solar chimney thermal power generating equipment was set up in China. A simulation study was carried out to investigate the performance of the power generating system based on a developed mathematical model. The simulated power outputs in steady state were obtained for different global solar radiation intensity, collector area and chimney height. By intercomparison, it is found

  8. Large scale solar thermal power generation

    Microsoft Academic Search

    B. McNelis

    1979-01-01

    Solar power generation options are reviewed and particular consideration is given to the central receiver system. It is noted that a 100 MW plant in a sunny region would employ about 15,000 heliostats, each with an area of 35 sq m, a central tower about 260 m high, and would cover an area of about 1.2 sq km. The plant

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

    E-print Network

    Sanders, Seth

    Low-cost distributed solar-thermal-electric power generation A. Der Minassians, K. H. Aschenbach discuss the technical and economic feasibility of a low-cost distributed solar-thermal-electric power relative cost, solar electric energy systems have yet to be exploited on a widespread basis. It is believed

  10. Device for thermal transfer and power generation

    DOEpatents

    Weaver, Stanton Earl (Northville, NY); Arik, Mehmet (Niskayuna, NY)

    2011-04-19

    A system is provided. The system includes a device that includes top and bottom thermally conductive substrates positioned opposite to one another, wherein a top surface of the bottom thermally conductive substrate is substantially atomically flat and a thermal blocking layer disposed between the top and bottom thermally conductive substrates. The device also includes top and bottom electrodes separated from one another between the top and bottom thermally conductive substrates to define a tunneling path, wherein the top electrode is disposed on the thermal blocking layer and the bottom electrode is disposed on the bottom thermally conductive substrate.

  11. Thermal investigation of a micro-gap thermionic power generator

    NASA Astrophysics Data System (ADS)

    Yacine Belbachir, Remi; An, Zhonglie; Ono, Takahito

    2014-08-01

    The demand for safe and clean energy sources has become more important than ever worldwide. Thermionic power generation is one of these energy sources, which directly converts heat into electrical energy using thermionic electrons. We developed a micro-gap thermionic power generator, which operates at relatively low temperature using SiC as an emitter. Electrons are emitted and travel from the heated SiC emitter to the collector electrode by thermionic emission. In this work, we have firstly demonstrated low temperature operation at 830?oC as a result of micro-gap between the emitter and collector electrodes. An output power density of 11.5?mW/cm2 is obtained. In addition, the heat losses from the emitter electrode are evaluated. Thermal conduction to the collector is by far the predominant thermal loss. In order to validate this result, a thermal resistance measurement device is built and the thermal resistance of the micro-gap is measured. Its value of 2.4?K/W allows for estimating in a more realistic way the heat loss by thermal conduction from the emitter to the collector via the gap. The newly estimated value still corresponds to a predominant thermal loss, hence highlighting the need for downsizing the SiO2 columns of the micro-gap in order to increase the power conversion efficiency.

  12. Recent advances in direct solar thermal power generation

    Microsoft Academic Search

    Yue-Guang Deng; Jing Liu

    2009-01-01

    The recent energy crisis and environmental burden are becoming increasingly urgent and drawing enormous attention to solar-energy utilization. Direct solar thermal power generation technologies, such as thermoelectric, thermionic, magnetohydrodynamic, and alkali-metal thermoelectric methods, are among the most attractive ways to provide electric energy from solar heat. On the one hand, these methods have the potential to be more efficient than

  13. Solar thermal power generation: the solar tower, progress toward commercialization

    Microsoft Academic Search

    Vant-Hull

    1985-01-01

    In August of 1984 a utility assumed independent operation of Solar One. This ten Megawatt electric (MW\\/sub e\\/) solar powered thermal generating plant is now operated by Southern California Edison as an integrated part of its plant mix. During a three-year period, detailed records will be kept to determine operating cost, availability, capacity factor, reliability, performance, failure modes, degradation rates,

  14. Stirling Engines for Low-Temperature Solar-Thermal-Electric Power Generation

    E-print Network

    Sanders, Seth

    Stirling Engines for Low-Temperature Solar-Thermal- Electric Power Generation Artin Der Minassians-Temperature Solar-Thermal-Electric Power Generation by Artin Der Minassians Karshenasi (Amirkabir University-Temperature Solar-Thermal-Electric Power Generation Copyright c 2007 by Artin Der Minassians #12;1 Abstract Stirling

  15. Advanced Stirling Radioisotope Generator (ASRG) Thermal Power Model in MATLAB

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen, J.

    2012-01-01

    This paper presents a one-dimensional steady-state mathematical thermal power model of the ASRG. It aims to provide a guideline of understanding how the ASRG works and what can change its performance. The thermal dynamics and energy balance of the generator is explained using the thermal circuit of the ASRG. The Stirling convertor performance map is used to represent the convertor. How the convertor performance map is coupled in the thermal circuit is explained. The ASRG performance characteristics under i) different sink temperatures and ii) over the years of mission (YOM) are predicted using the one-dimensional model. Two Stirling converter control strategies, i) fixing the hot-end of temperature of the convertor by adjusting piston amplitude and ii) fixing the piston amplitude, were tested in the model. Numerical results show that the first control strategy can result in a higher system efficiency than the second control strategy when the ambient gets warmer or the general-purpose heat source (GPHS) fuel load decays over the YOM. The ASRG performance data presented in this paper doesn't pertain to the ASRG flight unit. Some data of the ASRG engineering unit (EU) and flight unit that are available in public domain are used in this paper for the purpose of numerical studies.

  16. Solar thermal power generation. A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Bibliographies and abstracts are cited under the following topics: (1) energy overviews; (2) solar overviews; (3) conservation; (4) economics, law; (5) thermal power; (6) thermionic, thermoelectric; (7) ocean; (8) wind power; (9) biomass and photochemical; and (10) large photovoltaics.

  17. A novel gas adsorption cycle for solar thermal power generation

    Microsoft Academic Search

    T. L. Hartman Jr.; J. R. Williams

    1977-01-01

    The present configuration for solar thermal power towers are severly restricted by the low thermal efficiency which results from the temperature and pressure restriction under which they must operate. This paper presents a new thermodynamic cycle which, while operating under the same pressure and temperature restrictions, offer significantly increased performance. It should be noted that this cycle is not restricted

  18. Advanced Stirling Radioisotope Generator Thermal Power Model in Thermal Desktop SINDA/FLUINT Analyzer

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen; Fabanich, William A.; Schmitz, Paul C.

    2012-01-01

    This paper presents a three-dimensional Advanced Stirling Radioisotope Generator (ASRG) thermal power model that was built using the Thermal Desktop SINDA/FLUINT thermal analyzer. The model was correlated with ASRG engineering unit (EU) test data and ASRG flight unit predictions from Lockheed Martin's Ideas TMG thermal model. ASRG performance under (1) ASC hot-end temperatures, (2) ambient temperatures, and (3) years of mission for the general purpose heat source fuel decay was predicted using this model for the flight unit. The results were compared with those reported by Lockheed Martin and showed good agreement. In addition, the model was used to study the performance of the ASRG flight unit for operations on the ground and on the surface of Titan, and the concept of using gold film to reduce thermal loss through insulation was investigated.

  19. Comparative performance of solar thermal power generation concepts

    Microsoft Academic Search

    L. Wen; Y. C. Wu

    1976-01-01

    A performance comparison is made between the central receiver system (power tower) and a distributed system using either dishes or troughs and lines to transport fluids to the power station. These systems were analyzed at a rated capacity of 30 MW of thermal energy delivered in the form of superheated steam at 538 C (1000 F) and 68 atm (1000

  20. A thermally efficient micro-reactor for thermophotovoltaic power generation

    E-print Network

    Nielsen, Ole Mattis, 1977-

    2006-01-01

    Hydrocarbon fuels exhibit very high energy densities, and micro-generators converting the stored chemical energy into electrical power are interesting alternatives to batteries in certain applications. The increasing demands ...

  1. On-site solar-thermal electric power generation

    Microsoft Academic Search

    Curran

    1981-01-01

    Some aspects of using on-site solar power generation for buildings are studied, particularly in relation to Rankine\\/vapor compression cooling. On the basis of the results of the various studies, computer models, and project reports examined, one is led to the conclusion that for on-site power generation systems interfaced with electric utilities, dedicated storage is not required, and in most instances

  2. Commercialization of solar thermal power generation: policy issues

    Microsoft Academic Search

    Zuckerman

    1985-01-01

    Without the focused public attention which has been drawn to nuclear power, without the tremendous outpouring of financial assistance from the federal government which was applied to nuclear development, without even the more moderate financial support devoted to synthetic fuel production, the utilization of sun-power to generate electricity has come to technical feasibility. Not only has it been demonstrated, but

  3. Biomass supported solar thermal hybrid power plant for continuous electricity generation from renewable sources

    Microsoft Academic Search

    Shaheen Hasan Chowdhury; Amanullah Maung Than Oo; Palash Kumar Banerjee

    2012-01-01

    At present electricity generation from solar sources is being reached a remarkable edge. A large scale electrical energy can be generated using concentrating solar thermal hybrid power plant with storage system. It is fact that solar thermal power plant (STPP) cannot operate stably and continuously due to variability of solar irradiation. This paper proposed a optimal operating mode of hybrid

  4. A Feasibility Study of Solar Thermal Power Generation as the Pumping Power Source for Pumped Storage in Indonesia

    Microsoft Academic Search

    Tetsuya Funatsu; Hiroaki Natsume

    2009-01-01

    A pumped storage hydroelectric generation (PSHG) has been studied as alternative peak power source of the oil-fired power generation in Indonesia. However, because there is no surplus base load electricity even in the night, the economic advantage can not be found. The possibility of solar thermal power generation (STPG) is investigated to restrain the increase of fuel consumption by the

  5. Comparative performance of solar thermal power generation concepts

    NASA Technical Reports Server (NTRS)

    Wen, L.; Wu, Y. C.

    1976-01-01

    A performance comparison is made between the central receiver system (power tower) and a distributed system using either dishes or troughs and lines to transport fluids to the power station. These systems were analyzed at a rated capacity of 30 MW of thermal energy delivered in the form of superheated steam at 538 C (1000 F) and 68 atm (1000 psia), using consistent weather data, collector surface waviness, pointing error, and electric conversion efficiency. The comparisons include technical considerations for component requirements, land utilization, and annual thermal energy collection rates. The relative merits of different representative systems are dependent upon the overall conversion as expressed in the form of performance factors in this paper. These factors are essentially indices of the relative performance effectiveness for different concepts based upon unit collector area. These performance factors enable further economic tradeoff studies of systems to be made by comparing them with projected production costs for these systems.

  6. The development of a solar thermal water purification, heating, and power generation system: A case study.

    E-print Network

    Wu, Mingshen

    The development of a solar thermal water purification, heating, and power generation system: A case, none of the existing concentrated solar power systems (trough, dish, and tower) that have been the potential of an invention directed to a water purification system that also recovers power from generated

  7. Modeling of dish-Stirling solar thermal power generation

    Microsoft Academic Search

    Dustin Howard; Ronald G. Harley

    2010-01-01

    Dish-Stirling solar power generation has emerged as an efficient and reliable source of renewable energy. As the technology moves into commercialization, models become necessary to predict system behavior under various operating conditions. Current literature on dish-Stirling modeling is scattered, focusing on individual components within the system. This paper establishes a background of the individual component models, and provides a method

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

    Microsoft Academic Search

    Artin der Minassians

    2007-01-01

    This dissertation discusses the design and development of a distributed solar-thermal-electric power generation system that combines solar-thermal technology with a moderate-temperature Stirling engine to generate electricity. The conceived system incorporates low-cost materials and utilizes simple manufacturing processes. This technology is expected to achieve manufacturing cost of less than $1\\/W. Since solar-thermal technology is mature, the analysis, design, and experimental assessment

  9. Economic Evaluation of Solar Thermal Power Generation: a Case Study for Indian Conditions

    Microsoft Academic Search

    N. Singh; S. C. Kaushik

    1995-01-01

    This paper presents economic evaluation of solar thermal power generation for Indian conditions. The study incorporates case study of parabolic trough collector technology for power generation in 30 MW scale taking into account various options such as Solar Alone and Solar Hybrid. Sensitivity analysis by varying plant load factor, discount rate and the capital cost etc. has also been carried

  10. Solar-thermal electric power generation using a system of distributed parabolic trough collectors

    Microsoft Academic Search

    J. W. Ramsey; E. M. Sparrow; E. R. G. Eckert

    1975-01-01

    The paper describes a solar-thermal collection and transport system for electric power generation. The system employs water as the working fluid; steam at 60 bars pressure and 276 C is generated locally by distributed parabolic solar collectors. A transfer loop conveys the steam to a central site at which the power plant is situated. The design of the collector and

  11. Economic evaluation of solar thermal hybrid H 2O turbine power generation systems

    Microsoft Academic Search

    Takanobu Kosugi; Pyong Sik Pak

    2003-01-01

    The economics of two proposed solar thermal hybrid power generation systems (STHSs) have been evaluated. Each system consists of direct-steam-generation solar collectors, a steam accumulator and a gas turbine power generation system which uses steam as its working fluid. One (STHS-A) of the proposed systems emits CO2 generated by burning fuel, whereas the other (STHS-B) captures the CO2. Assuming that

  12. Power processing and control requirements of dispersed solar thermal electric generation systems

    NASA Technical Reports Server (NTRS)

    Das, R. L.

    1980-01-01

    Power Processing and Control requirements of Dispersed Receiver Solar Thermal Electric Generation Systems are presented. Kinematic Stirling Engines, Brayton Engines and Rankine Engines are considered as prime movers. Various types of generators are considered for ac and dc link generations. It is found that ac-ac Power Conversion is not suitable for implementation at this time. It is also found that ac-dc-ac Power Conversion with a large central inverter is more efficient than ac-dc-ac Power Conversion using small dispersed inverters. Ac-link solar thermal electric plants face potential stability and synchronization problems. Research and development efforts are needed in improving component performance characteristics and generation efficiency to make Solar Thermal Electric Generation economically attractive.

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

    NASA Astrophysics Data System (ADS)

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

    2004-01-01

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

  14. Analytical investigation of thermal barrier coatings on advanced power generation gas turbines

    NASA Technical Reports Server (NTRS)

    Amos, D. J.

    1977-01-01

    An analytical investigation of present and advanced gas turbine power generation cycles incorporating thermal barrier turbine component coatings was performed. Approximately 50 parametric points considering simple, recuperated, and combined cycles (including gasification) with gas turbine inlet temperatures from current levels through 1644K (2500 F) were evaluated. The results indicated that thermal barriers would be an attractive means to improve performance and reduce cost of electricity for these cycles. A recommended thermal barrier development program has been defined.

  15. Experimental investigation on a parabolic trough solar collector for thermal power generation

    Microsoft Academic Search

    QiBin Liu; YaLong Wang; ZhiChao Gao; Jun Sui; HongGuang Jin; HePing Li

    2010-01-01

    Developing solar thermal power technology in an effective manner is a great challenge in China. In this paper an experiment\\u000a platform of a parabolic trough solar collector system (PTCS) was developed for thermal power generation, and the performance\\u000a of the PTCS was experimentally investigated with synthetic oil as the circulate heat transfer fluid (HTF). The solar collector’s\\u000a efficiency with the

  16. Chemical energy storage system for Solar Electric Generating System (SEGS) solar thermal power plant

    Microsoft Academic Search

    D. R. Brown; J. L. LaMarche; G. E. Spanner

    1992-01-01

    This paper reports the Pacific Northwest Laboratory evaluated the potential feasibility of using chemical energy storage at the Solar Electric Generating System (SEGS) power plants developed by Luz International. Like sensible or latent heat energy storage systems, chemical energy storage can be beneficially applied to solar thermal power plants to dampen the impact of cloud transients, extend the daily operating

  17. Analytical investigation of thermal barrier coatings for advanced power generation combustion turbines

    NASA Technical Reports Server (NTRS)

    Amos, D. J.

    1977-01-01

    An analytical evaluation was conducted to determine quantitatively the improvement potential in cycle efficiency and cost of electricity made possible by the introduction of thermal barrier coatings to power generation combustion turbine systems. The thermal barrier system, a metallic bond coat and yttria stabilized zirconia outer layer applied by plasma spray techniques, acts as a heat insulator to provide substantial metal temperature reductions below that of the exposed thermal barrier surface. The study results show the thermal barrier to be a potentially attractive means for improving performance and reducing cost of electricity for the simple, recuperated, and combined cycles evaluated.

  18. Technical and economical evaluation of solar thermal power generation

    Microsoft Academic Search

    Theocharis Tsoutsos; Vasilis Gekas; Katerina Marketaki

    2003-01-01

    This article presents a feasibilty on a solar power system based on the Stirling dish (SD) technology, reviews and compares the available Stirling engines in the perspective of a solar Stirling system.The system is evaluated, as a parameter to alleviate the energy system of the Cretan island while taking care of the CO2 emissions. In the results a sensitivity analysis

  19. Anqing to the development of solar thermal power generation industry

    Microsoft Academic Search

    Shen Junchang; Yu Xianjin; Wu Hanjiang; Sun Bangyan; Dai Zhiguo; Ding Kaiming; Zhang Zhan

    2008-01-01

    This paper initial on the solar parabolic trough collectors, compact Fresnel linear reflector (CLFR). And they in the integration of fossil-fired power plant Kirchmoser (Germany) Staudinger5 (Germany) Stanwell (Australia) etc., of the application, and China development of solar energy, analyses the possibility, necessity and feasibility of the development of solar energy in Anqing. Seizing the opportunity, to strive for integration

  20. A NOVEL SOLAR THERMAL COMBINED CYCLE FOR DISTRIBUTED POWER GENERATION

    EPA Science Inventory

    Impacts of this work will be seen in the areas of energy, poverty alleviation, improvement of quality of health care provision and quality of life, business development, and education. We will be directly preventing installation of polluting diesel generators while improving ...

  1. Thermal and chemical tests of the steam generator of unit 3 at the Kalinin nuclear power station

    NASA Astrophysics Data System (ADS)

    Davidenko, N. N.; Trunov, N. B.; Saakov, E. S.; Berezanin, A. A.; Bogomolov, I. N.; Derii, V. P.; Nemytov, D. S.; Usanov, D. A.; Shestakov, N. B.; Shchelik, S. V.

    2007-12-01

    The results obtained from combined thermal and chemical tests of the steam generator of Unit 3 at the Kalinin nuclear power station are summarized. The obtained data are compared with the results of thermal and chemical tests carried out on steam generators at other nuclear power stations equipped with VVER-1000 reactors, and recommendations on selecting the steam-generator blowdown schedule are given.

  2. Light-Beam Sensorless Control of Heliostats for Tower Type Solar Thermal Power Generation Applications

    Microsoft Academic Search

    Xun Ma; Ping Wang

    2010-01-01

    This paper presents a method for the control of heliostats for the tower type solar thermal power generation applications without the light beam sensor, including solar position sensor and projection light sensor. Theoretically, sensorless control is not a no-error control, so the paper also presents some methods to eliminate the steady-state control error in engineering applications.

  3. The application of aerospace technology to solar thermal electric power generation

    Microsoft Academic Search

    R. W. Hallet Jr.

    1977-01-01

    ERDA has established a program plan for the development of technology which will make the utilization of solar energy possible. One goal established in this connection is to provide 40,000 MW of electric power generating capacity from solar thermal electric systems by the year 2000. According to the central receiver concept, solar rays are reflected from two axis tracking heliostats

  4. A hybrid power generation system utilizing solar thermal energy with CO 2 recovery based on oxygen combustion method

    Microsoft Academic Search

    Pyong Sik Pak; Takeshi Hatikawa; Yutaka Suzuki

    1995-01-01

    A CO2-recovering power generation system utilizing solar thermal energy was proposed. In the system, relatively low temperature saturated steam around 200 °C is produced by using solar thermal energy and is utilized as the working fluid of a gas turbine in which generated CO2 is recovered based on the method of oxygen combustion. Solar thermal utilization efficiency becomes considerably high

  5. Quantity, quality, and availability of waste heat from United States thermal power generation

    DOE PAGESBeta

    Gingerich, Daniel B; Mauter, Meagan S

    2015-06-10

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

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

    PubMed

    Gingerich, Daniel B; Mauter, Meagan S

    2015-07-21

    Secondary application of unconverted heat produced during electric power generation has the potential to improve the life-cycle fuel efficiency of the electric power industry and the sectors it serves. This work quantifies the residual heat (also known as waste heat) generated by U.S. thermal power plants and assesses the intermittency and transport issues that must be considered when planning to utilize this heat. Combining Energy Information Administration plant-level data with literature-reported process efficiency data, we develop estimates of the unconverted heat flux from individual U.S. thermal power plants in 2012. Together these power plants discharged an estimated 18.9 billion GJth of residual heat in 2012, 4% of which was discharged at temperatures greater than 90 °C. We also characterize the temperature, spatial distribution, and temporal availability of this residual heat at the plant level and model the implications for the technical and economic feasibility of its end use. Increased implementation of flue gas desulfurization technologies at coal-fired facilities and the higher quality heat generated in the exhaust of natural gas fuel cycles are expected to increase the availability of residual heat generated by 10.6% in 2040. PMID:26061407

  7. Quantity, quality, and availability of waste heat from United States thermal power generation

    DOE PAGESBeta

    Gingerich, Daniel B [Carnegie Mellon Univ., Pittsburgh, PA (United States); Mauter, Meagan S [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2015-06-10

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

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

    DOEpatents

    Bowman, C.D.

    1992-11-03

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

  9. The challenges of fuel options for the new generation of Indian thermal power plants

    SciTech Connect

    Roy, C.; Sanyal, A.

    1999-07-01

    The selection of fuel supply is probably the most important challenge a potential power project developer for a new Indian thermal power plant has to face when considering the overall project economics. The paper reviews the essential issues and the effect of fuel selection on project costs of the new generation of thermal power plants of India. Coal, lignite and natural gas are India's indigenous fossil fuel resources for power generation. The country has a modest reserve of petroleum crude. India is the world's third largest coal producer and has 205 billion metric tons of assessed and 73 billion tons of proven reserves. The indigenous supply of petroleum is unlikely to improve much in the near future. Liquid fuel based generation is therefore marginal in the country. Although coal will continue to be the mainstay fuel, there is a short term need to examine the possibility of using alternative fuels due to two basic reasons: (a) A 70 million tons of shortfall is forecast for the power sector during the 1997--2002 period. The deficit has to be met by either import of coal or other fuels. Development of new mines is a long gestation activity. (b) There is an uneven geographical location of Indian coal reserves. For the load centers, which are distant from the indigenous coal sources, use of alternative fuel could also prove to be economical in the long term. Moving coal will become harder in view of the high demands being placed on the railways by many other sectors.

  10. Horizontal Steam Generator Thermal-Hydraulics at Various Steady-State Power Levels

    Microsoft Academic Search

    Vladimir D. Stevanovic; Zoran V. Stosic; Michael Kiera; Uwe Stoll

    2002-01-01

    Three-dimensional computer simulation and analyses of the horizontal steam generator thermal-hydraulics of the WWER 1000 nuclear power plant have been performed for 50% and 75% partial loads, 100% nominal load and 110% over-load. Presented results show water and steam mass flow rate vectors, steam void fraction spatial distribution, recirculation zones, swell level position, water mass inventory on the shell side,

  11. Horizontal Steam Generator Thermal-Hydraulics at Various Steady-State Power Levels

    SciTech Connect

    Stevanovic, Vladimir D. [University of Belgrade, Kraljice Marije 16, 11000 Belgrade, Serbia and Montenegro (Yugoslavia); Stosic, Zoran V.; Kiera, Michael; Stoll, Uwe [Framatome ANP GmbH, P.O. Box 3220, 91050 Erlangen (Germany)

    2002-07-01

    Three-dimensional computer simulation and analyses of the horizontal steam generator thermal-hydraulics of the WWER 1000 nuclear power plant have been performed for 50% and 75% partial loads, 100% nominal load and 110% over-load. Presented results show water and steam mass flow rate vectors, steam void fraction spatial distribution, recirculation zones, swell level position, water mass inventory on the shell side, and other important thermal-hydraulic parameters. The simulations have been performed with the computer code 3D ANA, based on the 'two-fluid' model approach. Steam-water interface transport processes, as well as tube bundle flow resistance, energy transfer, and steam generation within tube bundles are modelled with {sup c}losure laws{sup .} Applied approach implies non-equilibrium thermal and flow conditions. The model is solved by the control volume procedure, which has been extended in order to take into account the 3D flow of liquid and gas phase. The methodology is validated by comparing numerical and experimental results of real steam generator operational conditions at various power levels of the WWER Novovoronezh, Unit 5. One-dimensional model of the horizontal steam generator has been built with the RELAP 5 standard code on the basis of the multidimensional two-phase flow structure obtained with the 3D ANA code. RELAP 5 and 3D ANA code results are compared, showing acceptable agreement. (authors)

  12. State of the art on high temperature thermal energy storage for power generation. Part 1—Concepts, materials and modellization

    Microsoft Academic Search

    Antoni Gil; Marc Medrano; Ingrid Martorell; Ana Lázaro; Pablo Dolado; Belén Zalba; Luisa F. Cabeza

    2010-01-01

    Concentrated solar thermal power generation is becoming a very attractive renewable energy production system among all the different renewable options, as it has have a better potential for dispatchability. This dispatchability is inevitably linked with an efficient and cost-effective thermal storage system. Thus, of all components, thermal storage is a key one. However, it is also one of the less

  13. Performance of a direct steam generation solar thermal power plant for electricity production as a function of the solar multiple

    Microsoft Academic Search

    M. J. Montes; A. Abánades; J. M. Martínez-Val

    2009-01-01

    This paper describes the influence of the solar multiple on the annual performance of parabolic trough solar thermal power plants with direct steam generation (DSG). The reference system selected is a 50MWe DSG power plant, with thermal storage and auxiliary natural gas-fired boiler. It is considered that both systems are necessary for an optimum coupling to the electricity grid. Although

  14. Performance and economics of a solar thermal power generation plant in Jubail, Saudi Arabia: Parabolic trough collector

    Microsoft Academic Search

    Adel M. Al-Nasser

    2010-01-01

    The study explores the technical and economic feasibility of a thermal solar power generation plant using parabolic trough collectors (Euro Trough) in Jubail Industrial City, Saudi Arabia. Total annual available solar radiation is calculated at 1,970 kWhr. The size of the proposed solar thermal power plant is 50 MW. The designed solar field is composed of 100 loops with a

  15. Near-field radiative transfer: Thermal radiation, thermophotovoltaic power generation and optical characterization

    NASA Astrophysics Data System (ADS)

    Francoeur, Mathieu

    This dissertation focuses on near-field radiative transfer, which can be defined as the discipline concerned with energy transfer via electromagnetic waves at sub-wavelength distances. Three specific subjects related to this discipline are investigated, namely near-field thermal radiation, nanoscale-gap thermophotovoltaic (nano-TPV) power generation and optical characterization. An algorithm for the solution of near-field thermal radiation problems in one-dimensional layered media is developed, and several tests are performed showing the accuracy, consistency and versatility of the procedure. The possibility of tuning near-field radiative heat transfer via thin films supporting surface phonon-polaritons (SPhPs) in the infrared is afterwards investigated via the computation of the local density of electromagnetic states and the radiative heat flux between two films. Results reveal that due to SPhP coupling, fine tuning of near-field radiative heat transfer is possible by solely varying the structure of the system, the structure being the film thicknesses and their distance of separation. The coexistence of two regimes of near-field thermal radiation between two thin films of silicon carbide is demonstrated via numerical simulations and an asymptotic analysis of the radiative heat transfer coefficient. The impacts of thermal effects on the performances of nano-TPV power generators are investigated via the solution of the coupled near-field thermal radiation, charge and heat transport problem. The viability of nano-TPV devices proposed so far in the literature, based on a tungsten radiator at 2000 K and indium gallium antimonide cell, is questioned due to excessive heating of the junction converting thermal radiation into electricity. Using a convective thermal management system, a heat transfer coefficient as high as 105 Wm-2K-1 is required to maintain the junction at room temperature. The possibility of characterizing non-intrusively, and potentially in real-time, nanoparticles from 5 nm to 100 nm in size via scattered surface wave is explored. The feasibility of the characterization framework is theoretically demonstrated via a sensitivity analysis of the scattering matrix elements. Measurements of the scattering matrix elements for 200 nm and 50 nm gold spherical particles show the great sensitivity of the characterization tool, although an ultimate calibration is difficult with the current version of the experimental set-up. KEYWORDS: Near-field thermal radiation, Surface phonon-polariton, Nanoscale-gap thermophotoltaic power generation, Optical characterization of nanoparticles, Scattering (Mueller) matrix

  16. The combined hybrid system: A symbiotic thermal reactor\\/fast reactor system for power generation and radioactive waste toxicity reduction

    Microsoft Academic Search

    Hollaway

    1991-01-01

    If there is to be a next generation of nuclear power in the United States, then the four fundamental obstacles confronting nuclear power technology must be overcome: safety, cost, waste management, and proliferation resistance. The Combined Hybrid System (CHS) is proposed as a possible solution to the problems preventing a vigorous resurgence of nuclear power. The CHS combines Thermal Reactors

  17. Solar thermal power generation. A bibliography with abstracts. Quarterly update, April--June 1977. [148 citations

    Microsoft Academic Search

    Bell

    1977-01-01

    The bibliography contains 148 references to information on energy overviews, solar overviews, economics and law, thermal power, thermionic and thermoelectric, ocean thermal differential, wind conversion, bioconversion, residential, and other (hydrogen production, large-scale photovoltaic, etc.) (WHK)

  18. Novel Molten Salts Thermal Energy Storage for Concentrating Solar Power Generation

    SciTech Connect

    Reddy, Ramana G. [The University of Alabama] [The University of Alabama

    2013-10-23

    The explicit UA program objective is to develop low melting point (LMP) molten salt thermal energy storage media with high thermal energy storage density for sensible heat storage systems. The novel Low Melting Point (LMP) molten salts are targeted to have the following characteristics: 1. Lower melting point (MP) compared to current salts (<222ºC) 2. Higher energy density compared to current salts (>300 MJ/m3) 3. Lower power generation cost compared to current salt In terms of lower power costs, the program target the DOE's Solar Energy Technologies Program year 2020 goal to create systems that have the potential to reduce the cost of Thermal Energy Storage (TES) to less than $15/kWh-th and achieve round trip efficiencies greater than 93%. The project has completed the experimental investigations to determine the thermo-physical, long term thermal stability properties of the LMP molten salts and also corrosion studies of stainless steel in the candidate LMP molten salts. Heat transfer and fluid dynamics modeling have been conducted to identify heat transfer geometry and relative costs for TES systems that would utilize the primary LMP molten salt candidates. The project also proposes heat transfer geometry with relevant modifications to suit the usage of our molten salts as thermal energy storage and heat transfer fluids. The essential properties of the down-selected novel LMP molten salts to be considered for thermal storage in solar energy applications were experimentally determined, including melting point, heat capacity, thermal stability, density, viscosity, thermal conductivity, vapor pressure, and corrosion resistance of SS 316. The thermodynamic modeling was conducted to determine potential high temperature stable molten salt mixtures that have thermal stability up to 1000 °C. The thermo-physical properties of select potential high temperature stable (HMP) molten salt mixtures were also experimentally determined. All the salt mixtures align with the go/no-go goals stipulated by the DOE for this project. Energy densities of all salt mixtures were higher than that of the current solar salt. The salt mixtures costs have been estimated and TES system costs for a 2 tank, direct approach have been estimated for each of these materials. All estimated costs are significantly below the baseline system that used solar salt. These lower melt point salts offer significantly higher energy density per volume than solar salt – and therefore attractively smaller inventory and equipment costs. Moreover, a new TES system geometry has been recommended A variety of approaches were evaluated to use the low melting point molten salt. Two novel changes are recommended that 1) use the salt as a HTF through the solar trough field, and 2) use the salt to not only create steam but also to preheat the condensed feedwater for Rankine cycle. The two changes enable the powerblock to operate at 500°C, rather than the current 400°C obtainable using oil as the HTF. Secondly, the use of salt to preheat the feedwater eliminates the need to extract steam from the low pressure turbine for that purpose. Together, these changes result in a dramatic 63% reduction required for 6 hour salt inventory, a 72% reduction in storage volume, and a 24% reduction in steam flow rate in the power block. Round trip efficiency for the Case 5 - 2 tank “direct” system is estimated at >97%, with only small losses from time under storage and heat exchange, and meeting RFP goals. This attractive efficiency is available because the major heat loss experienced in a 2 tank “indirect” system - losses by transferring the thermal energy from oil HTF to the salt storage material and back to oil to run the steam generator at night - is not present for the 2 tank direct system. The higher heat capacity values for both LMP and HMP systems enable larger storage capacities for concentrating solar power.

  19. Solar thermal power plants

    Microsoft Academic Search

    L. Schnatbaum

    2009-01-01

    The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The\\u000a focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale.\\u000a In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of

  20. Solar thermal power generation: a bibliography with abstracts. Quarterly update, April-June 1980

    Microsoft Academic Search

    T. Sparkman; W. R. Bozman

    1980-01-01

    This annotated bibliography covers the following subjects: energy overviews; solar overviews; energy conservation; environment, law, and policy; total energy systems; solar thermal power and energy storage; thermoelectric, thermionic, and thermolysis; Ocean Thermal Energy Conversion; wind energy; biomass; bioconversion, and photochemical; satellite power systems; and photovoltaic applications. (MHR)

  1. Solar powered gas generation. [combined solar thermal power plant for electrolysis of seawater and solar still

    Microsoft Academic Search

    1978-01-01

    This invention relates to the utilization of solar energy by means of a reflector, a boiler and a turbogenerator whereby solar heat is concentrated and electric power is produced, utilization of the exhaust heat from the power cycle in the distillation of sea water, and utilization of the electric power in a plurality of electrolytic cells whereby hydrogen and oxygen

  2. THERMAL ANALYSIS OF PARABOLIC TROUGH SOLAR COLLECTORS FOR ELECTRIC POWER GENERATION

    Microsoft Academic Search

    S. D. Odeh; G. L. Morrison; M. Behnia

    The performance of parabolic trough solar collectors solar thermal electric generation systems is evaluated for Australian climate conditions. The largest Solar Electric Generation System (SEGS) currently in operation uses a parabolic trough solar collector and synthetic oil in the collector loop. To improve performance and reduce costs, future designs propose direct steam generation in the collector. In this study parabolic

  3. Quasi-steady state temperature distribution and numerical simulation on low Ste number latent heat storage thermal unit of solar thermal power generation

    Microsoft Academic Search

    J. Huang; D. S. Zhu

    2010-01-01

    Solar thermal power generation systems, including direct steam generation, require isothermal energy storage systems for a saturation temperature range between 190° C and 310° C. One option to fulfill this requirement is the application of phase-change materials to absorb or release energy. In this paper, the basic concept of latent heat storage system is described, and a model of phase-change

  4. SENSIBLE HEAT STORAGE FOR A SOLAR THERMAL POWER PLANT

    E-print Network

    Baldwin, Thomas F.

    2011-01-01

    the thermal efficiencies of power generation for both solarPower Generation, Discharging, MWe Net Thermal Efficiency of the Solarsolar power plant stores enough thermal energy to produce 100.0 MW gross power generation

  5. Solar Thermal Power.

    ERIC Educational Resources Information Center

    McDaniels, David K.

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

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

    Microsoft Academic Search

    Brian Norton; Phillip C Eames; Steve NG Lo

    1998-01-01

    Renewable energy generation of electricity is advocated as a means of reducing carbon dioxide emissions associated with the generation from fossil fuels. Whilst it is true that renewable sources do not generate significant carbon dioxide whilst producing electricity, as with fossil-fuelled plants they do embody significant emissions in their materials of construction. The “full-chain” environmental impacts of wind, hydro, solar-thermal

  7. Thermal effects in high-power CW second harmonic generation in Mg-doped stoichiometric lithium tantalate.

    PubMed

    Tovstonog, Sergey V; Kurimura, Sunao; Suzuki, Ikue; Takeno, Kohei; Moriwaki, Shigenori; Ohmae, Noriaki; Mio, Norikatsu; Katagai, Toshio

    2008-07-21

    We investigated thermal behaviors of single-pass second-harmonic generation of continuous wave green radiation with high efficiency by quasi-phase matching in periodically poled Mg-doped stoichiometric lithium tantalate (PPMgSLT). Heat generation turned out to be directly related to the green light absorption in the material. Strong relation between an upper limit of the second harmonic power and confocal parameter was found. Single-pass second-harmonic generation of 16.1 W green power was achieved with 17.6% efficiency in Mg:SLT at room temperature. PMID:18648448

  8. Design and thermal analysis of a two stage solar concentrator for combined heat and thermoelectric power generation

    Microsoft Academic Search

    Siddig A. Omer; David G. Infield

    2000-01-01

    A design procedure and thermal performance analysis of a two stage solar energy concentrator suited to combined heat and thermoelectric power generation are presented. The concentrator is comprised of a primary one axis parabolic trough concentrator and a second stage compound parabolic concentrator mounted at the focus of the primary. The thermoelectric device is attached to the absorber plate at

  9. Development and Demonstration of an Innovative Thermal Energy Storage System for Baseload Power Generation

    SciTech Connect

    D. Y. Goswami

    2012-09-04

    The objective of this project is to research and develop a thermal energy storage system (operating range 3000C ���¢�������� 450 0C ) based on encapsulated phase change materials (PCM) that can meet the utility-scale base-load concentrated solar power plant requirements at much lower system costs compared to the existing thermal energy storage (TES) concepts. The major focus of this program is to develop suitable encapsulation methods for existing low-cost phase change materials that would provide a cost effective and reliable solution for thermal energy storage to be integrated in solar thermal power plants. This project proposes a TES system concept that will allow for an increase of the capacity factor of the present CSP technologies to 75% or greater and reduce the cost to less than $20/kWht.

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

    PubMed Central

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

    2015-01-01

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

  11. A Life Cycle Assessment (LCA) of a Paraboloidal-Dish Solar Thermal Power Generation System

    Microsoft Academic Search

    Fausto Cavallaro; Luigi Ciraolo

    2006-01-01

    The principles regarding the conversion of solar thermal power have been known for more than a century, however its commercial exploitation and the construction of plants on an industrial scale did not occur until the mid 1980's. The first pilot plants that were built in various countries around the world tested their technological, economic and environmental performance and gave highly

  12. Solar thermal power generation in India—a techno–economic analysis

    Microsoft Academic Search

    S Beerbaum; G Weinrebe

    2000-01-01

    Limited fossil resources and environmental problems require new sustainable energy supply options, that use renewable energies and are economic at the same time. Solar Thermal Electricity (STE) generating systems are proven renewable energy technologies and often a very cost effective way to produce electricity from solar radiation.In India, the electricity demand is drastically increasing. At the same time, solar resources

  13. Solar Thermal Power Technologies

    NSDL National Science Digital Library

    Groenendaal, B.J.

    2002-01-01

    Published in July 2002 by the Energy Research Foundation of the Netherlands, this 50-page report describes current and future Solar Thermal Power technologies. It offers a unique perspective by looking ahead to the "global energy supply and demand until 2100." Five main technologies are described, and two are examined in depth. The first is a solar tower design that uses a large array of mirrors to reflect all sunlight to a receiver at the top of a tower, and then generates electricity from a steam-powered turbine. SNAP technology is the second focus; this kind of power plant directs artificially created wind down a large tube, turning turbines as the wind escapes. A short history of each of these methods is included, as well as an analysis of world solar power potential.

  14. Solar Thermal Electricity Generating System

    NASA Astrophysics Data System (ADS)

    Mishra, Sambeet; Tripathy, Pratyasha

    2012-08-01

    A Solar Thermal Electricity generating system also known as Solar Thermal Power plant is an emerging renewable energy technology, where we generate the thermal energy by concentrating and converting the direct solar radiationat medium/high temperature (300?C ñ 800?C). The resulting thermal energy is then used in a thermodynamic cycleto produce electricity, by running a heat engine, which turns a generator to make electricity. Solar thermal power is currently paving the way for the most cost-effective solar technology on a large scale and is heading to establish a cleaner, pollution free and secured future. Photovoltaic (PV) and solar thermal technologies are two main ways of generating energy from the sun, which is considered the inexhaustible source of energy. PV converts sunlight directly into electricity whereas in Solar thermal technology, heat from the sun's rays is concentrated to heat a fluid, whose steam powers a generator that produces electricity. It is similar to the way fossil fuel-burning power plants work except that the steam is produced by the collected heat rather than from the combustion of fossil fuels. In order to generate electricity, five major varieties of solar thermal technologies used are:* Parabolic Trough Solar Electric Generating System (SEGS).* Central Receiver Power Plant.* Solar Chimney Power Plant.* Dish Sterling System.* Solar Pond Power Plant.Most parts of India,Asia experiences a clear sunny weather for about 250 to 300 days a year, because of its location in the equatorial sun belt of the earth, receiving fairly large amount of radiation as compared to many parts of the world especially Japan, Europe and the US where development and deployment of solar technologies is maximum.Whether accompanied with this benefit or not, usually we have to concentrate the solar radiation in order to compensate for the attenuation of solar radiation in its way to earthís surface, which results in from 63,2 GW/m2 at the Sun to 1 kW/m2 at Earth¥s surface. The higher the concentration, the higher the temperatures we can achieve when converting solar radiation into thermal energy

  15. Next generation cooled long range thermal sights with minimum size, weight, and power

    NASA Astrophysics Data System (ADS)

    Breiter, R.; Ihle, T.; Wendler, J.; Rühlich, I.; Ziegler, J.

    2013-06-01

    Situational awareness and precise targeting at day, night and severe weather conditions are key elements for mission success in asymmetric warfare. To support these capabilities for the dismounted soldier, AIM has developed a family of stand-alone thermal weapon sights based on high performance cooled IR-modules which are used e.g. in the infantryman of the future program of the German army (IdZ). The design driver for these sights is a long ID range <1500m for the NATO standard target to cover the operational range of a platoon with the engagement range of .50 cal rifles, 40mm AGLs or for reconnaissance tasks. The most recent sight WBZG has just entered into serial production for the IdZ enhanced system of the German army with additional capabilities like a wireless data link to the soldier backbone computer. Minimum size, weight and power (SWaP) are most critical requirements for the dismounted soldiers' equipment and sometimes push a decision towards uncooled equipment with marginal performance referring to the outstanding challenges in current asymmetric warfare, e.g. the capability to distinguish between combatants and non-combatants in adequate ranges. To provide the uncompromised e/o performance with SWaP parameters close to uncooled, AIM has developed a new thermal weapon sight based on high operating temperature (HOT) MCT MWIR FPAs together with a new low power single piston stirling cooler. In basic operation the sight is used as a clip-on in front of the rifle scope. An additional eyepiece for stand-alone targeting with e.g. AGLs or a biocular version for relaxed surveillance will be available. The paper will present details of the technologies applied for such long range cooled sights with size, weight and power close to uncooled.

  16. Solar thermal power system

    DOEpatents

    Bennett, Charles L.

    2010-06-15

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

  17. Thermal power loops

    NASA Technical Reports Server (NTRS)

    Gottschlich, Joseph M.; Richter, Robert

    1991-01-01

    The concept of a thermal power loop (TPL) to transport thermal power over relatively large distances is presented as an alternative to heat pipes and their derivatives. The TPL is compared to heat pipes, and capillary pumped loops with respect to size, weight, conservation of thermal potential, start-up, and 1-g testing capability. Test results from a proof of feasibility demonstrator at the NASA JPL are discussed. This analysis demonstrates that the development of specific thermal power loops will result in substantial weight and cost savings for many spacecraft.

  18. The combined hybrid system: A symbiotic thermal reactor/fast reactor system for power generation and radioactive waste toxicity reduction

    SciTech Connect

    Hollaway, W.R.

    1991-08-01

    If there is to be a next generation of nuclear power in the United States, then the four fundamental obstacles confronting nuclear power technology must be overcome: safety, cost, waste management, and proliferation resistance. The Combined Hybrid System (CHS) is proposed as a possible solution to the problems preventing a vigorous resurgence of nuclear power. The CHS combines Thermal Reactors (for operability, safety, and cost) and Integral Fast Reactors (for waste treatment and actinide burning) in a symbiotic large scale system. The CHS addresses the safety and cost issues through the use of advanced reactor designs, the waste management issue through the use of actinide burning, and the proliferation resistance issue through the use of an integral fuel cycle with co-located components. There are nine major components in the Combined Hybrid System linked by nineteen nuclear material mass flow streams. A computer code, CHASM, is used to analyze the mass flow rates CHS, and the reactor support ratio (the ratio of thermal/fast reactors), IFR of the system. The primary advantages of the CHS are its essentially actinide-free high-level radioactive waste, plus improved reactor safety, uranium utilization, and widening of the option base. The primary disadvantages of the CHS are the large capacity of IFRs required (approximately one MW{sub e} IFR capacity for every three MW{sub e} Thermal Reactor) and the novel radioactive waste streams produced by the CHS. The capability of the IFR to burn pure transuranic fuel, a primary assumption of this study, has yet to be proven. The Combined Hybrid System represents an attractive option for future nuclear power development; that disposal of the essentially actinide-free radioactive waste produced by the CHS provides an excellent alternative to the disposal of intact actinide-bearing Light Water Reactor spent fuel (reducing the toxicity based lifetime of the waste from roughly 360,000 years to about 510 years).

  19. Investigation and analysis on the combined operation of solar thermal power and conventional thermal power

    Microsoft Academic Search

    D. Y. Liu; J. Wang; X. Q. Feng; S. Guo; C. Xu

    2009-01-01

    The main constitution and the performance characteristic of Solar Thermal Power System (STPS) were introduced, and the thermal losses law of the recycled working substance of the conventional thermal power generation unit was analyzed in this paper. The key technical choke points currently existing in high-temperature solar thermal power system were demonstrated in the aspect of technical feasibility and economical

  20. Daily Integrated Generation Scheduling for Thermal, Pumped-Storage Hydro and Cascaded Hydro Units and Purchasing Power Considering Network Constraints

    NASA Astrophysics Data System (ADS)

    Sawa, Toshiyuki; Sato, Yasuo; Tsurugai, Mitsuo; Onishi, Tsukasa

    We have developed an innovative power generation scheduling method using quadratic programming (QP). The advantage of using our method is that it simultaneously solves unit commitment and economic load dispatch. We relax the binary variables of the unit state into continuous variables to apply QP to this problem. We also add the penalty term to converge the value of those variables to 0 or 1 to the objective function; the sum of fuel costs and start-up costs. This penalty term depends on per-unit fuel cost. The possibility of its variable converging to zero increases as the cost increases. This method was applied to a test system of daily generation scheduling that consisted of 29 thermal units, two pumped-storage units, four cascaded-hydro units, and one transmission. The schedule satisfied all constraints, i.e., load-power balance, operation reserve, power flow, minimum up/down-times, and fuel consumption. This result shows that the developed method is effective.

  1. Quasi-steady state temperature distribution and numerical simulation on low Ste number latent heat storage thermal unit of solar thermal power generation

    NASA Astrophysics Data System (ADS)

    Huang, J.; Zhu, D. S.

    2010-03-01

    Solar thermal power generation systems, including direct steam generation, require isothermal energy storage systems for a saturation temperature range between 190° C and 310° C. One option to fulfill this requirement is the application of phase-change materials to absorb or release energy. In this paper, the basic concept of latent heat storage system is described, and a model of phase-change heat transfer of latent heat storage thermal unit for thermal energy storage system is built. Base on the practical thermo-physical properties of phase-change materials, Quasi-Steady State temperature distribution of phase-change heat transfer is analyzed under low Ste number. Numerical simulation (finite element method) taking account into the sensible heat is adopted and the results prove that the Quasi-Steady State temperature distribution obtained from theoretical is in good agreement with the results of numerical simulation. For a latent heat storage system with low Ste number characteristic, Quasi-Steady State solution can be used as the theoretical calculation foundation for engineering design.

  2. Potential benefits of a ceramic thermal barrier coating on large power generation gas turbine

    NASA Technical Reports Server (NTRS)

    Clark, J. S.; Nainiger, J. J.

    1977-01-01

    Thermal barrier coating design option offers benefit in terms of reduced electricity costs when used in utility gas turbines. Options considered include: increased firing temperature, increased component life, reduced cooling air requirements, and increased corrosion resistance (resulting in increased tolerance for dirty fuels). Performance and cost data were obtained. Simple, recuperated and combined cycle applications were considered, and distillate and residual fuels were assumed. The results indicate that thermal barrier coatings could produce large electricity cost savings if these coatings permit turbine operation with residual fuels at distillate-rated firing temperatures. The results also show that increased turbine inlet temperature can result in substantial savings in fuel and capital costs.

  3. MHD Power Generation

    ERIC Educational Resources Information Center

    Kantrowitz, Arthur; Rosa, Richard J.

    1975-01-01

    Explains the operation of the Magnetohydrodynamic (MHD) generator and advantages of the system over coal, oil or nuclear powered generators. Details the development of MHD generators in the United States and Soviet Union. (CP)

  4. Development and Performance Evaluation of High Temperature Concrete for Thermal Energy Storage for Solar Power Generation

    SciTech Connect

    R. Panneer Selvam, Micah Hale and Matt strasser

    2013-03-31

    Thermal energy can be stored by the mechanism of sensible or latent heat or heat from chemical reactions. Sensible heat is the means of storing energy by increasing the temperature of the solid or liquid. Since the concrete as media cost per kWhthermal is $1, this seems to be a very economical material to be used as a TES. This research is focused on extending the concrete TES system for higher temperatures (500 �ºC to 600 �ºC) and increasing the heat transfer performance using novel construction techniques. To store heat at high temperature special concretes are developed and tested for its performance. The storage capacity costs of the developed concrete is in the range of $0.91-$3.02/kWhthermal Two different storage methods are investigated. In the first one heat is transported using molten slat through a stainless steel tube and heat is transported into concrete block through diffusion. The cost of the system is higher than the targeted DOE goal of $15/kWhthermal The increase in cost of the system is due to stainless steel tube to transfer the heat from molten salt to the concrete blocks.The other method is a one-tank thermocline system in which both the hot and cold fluid occupy the same tank resulting in reduced storage tank volume. In this model, heated molten salt enters the top of the tank which contains a packed bed of quartzite rock and silica sand as the thermal energy storage (TES) medium. The single-tank storage system uses about half the salt that is required by the two-tank system for a required storage capacity. This amounts to a significant reduction in the cost of the storage system. The single tank alternative has also been proven to be cheaper than the option which uses large concrete modules with embedded heat exchangers. Using computer models optimum dimensions are determined to have an round trip efficiency of 84%. Additionally, the cost of the structured concrete thermocline configuration provides the TES capacity cost of $33.80$/kWhthermal compared with $30.04/kWhthermal for a packed-bed thermocline (PBTC) configuration and $46.11/kWhthermal for a two-tank liquid configuration.

  5. Economic analysis of power generation from parabolic trough solar thermal plants for the Mediterranean region—A case study for the island of Cyprus

    Microsoft Academic Search

    Andreas Poullikkas

    2009-01-01

    In this work a feasibility study is carried out in order to investigate whether the installation of a parabolic trough solar thermal technology for power generation in the Mediterranean region is economically feasible. The case study takes into account the available solar potential for Cyprus, as well as all available data concerning current renewable energy sources policy of the Cyprus

  6. Solar thermal power

    Microsoft Academic Search

    T. R. Mancini; G. J. Kolb; M. R. Prairie

    1997-01-01

    Solar thermal power is produced by three types of concentrating systems, which utilize parabolic troughs, dishes, and heliostats as the solar concentrators. These systems are at various levels of development and commercialization in the United States and in Europe. The U.S. Industry is currently developing these systems for export at the end of this century and at the beginning of

  7. Second Law analysis of a Rankine heat engine with reheat and regenerative options for solar thermal power generation

    Microsoft Academic Search

    S. C. Kaushik; R. D. Misra; N. Singh

    2000-01-01

    This communication presents the Second Law analysis based on the exergy concept for the performance of Simple and Regenerative-Reheat Rankine heat engines generally used in Solar Thermal Power Systems. Basic energy and exergy analysis for the heat engine system components are carried out for evaluating the energy and exergy losses as well as the exergetic efficiencies for both the Simple

  8. A Novel Solar Thermal Power Plant with Floating Chimney Stiffened onto a Mountainside and Potential of the Power Generation in China's Deserts

    Microsoft Academic Search

    Xinping Zhou; Jiakuan Yang

    2009-01-01

    A novel solar thermal power plant with a floating chimney stiffened on a mountainside segment by segment is proposed. The novel power plant is suitable for the special topography in China (i.e., a vast desert belt surrounded by high mountain chains up to thousands of meters). An investigation of its performance is carried out using a simple mathematical model. The

  9. High peak power generation in thermally bonded Er3+, Yb3+:glass/Co2+: MgAl2O3 microchip laser for telemetry application

    NASA Astrophysics Data System (ADS)

    Mlynczak, Jaroslaw; Belghachem, Nabil

    2015-04-01

    The highest ever reported peak power generation of 7.68?kW in thermally bonded active medium Er3+,Yb3+:glass with saturable absorber Co2+: MgAl2O3 was achieved. The sample was a quasi-continuous wave pumped by a fiber coupled laser diode operating at 975?nm wavelength. The generation threshold was 319?mW and slope efficiency was 9.63%. A comparative analysis of the generation of different output coupler transmissions is presented.

  10. Electrical power generating system. [for windpowered generation

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (inventor)

    1981-01-01

    An alternating current power generation system adopted to inject power in an already powered power line is discussed. The power generating system solves to adjustably coup an induction motor, as a generator, to an ac power line wherein the motor and power line are connected through a triac. The triac is regulated to normally turn on at a relatively late point in each half cycle of its operation, whereby at less than operating speed, and thus when the induction motor functions as a motor rather than as a generator, power consumption from the line is substantially reduced. The principal application will be for windmill powered generation.

  11. Thermal batteries for aircraft emergency power

    SciTech Connect

    Ryan, D.M.

    1993-01-01

    Thermal batteries are being proposed for the Emergency Power System for aircraft. Thermal batteries are a reserve type battery which is essentially inert until activated. Thermal batteries can generate full power in several seconds and nominally produce 20 WHr/Ib and operate over a temperature range of -65 deg to 165 deg. Thermal batteries have a proven field storage life exceeding 25 years. They contain no liquids, can be maintained at any attitude, operate at any altitude, and do not leak any toxic or noxious materials. Expended thermal batteries contain no lead or cadmium and do not represent a significant disposal or environmental problem. Thermal batteries have a thirty year history of excellent performance providing on-board power for missiles and other weapons and have a proven safety record with no field injuries ever. Thermal batteries have a relatively low cost of initial ownership and require no maintenance.

  12. Thermal batteries for aircraft emergency power

    NASA Astrophysics Data System (ADS)

    Ryan, David M.

    1993-02-01

    Thermal batteries are being proposed for the Emergency Power System for aircraft. Thermal batteries are a reserve type battery which is essentially inert until activated. Thermal batteries can generate full power in several seconds and nominally produce 20 WHr/Ib and operate over a temperature range of -65 deg to 165 deg. Thermal batteries have a proven field storage life exceeding 25 years. They contain no liquids, can be maintained at any attitude, operate at any altitude, and do not leak any toxic or noxious materials. Expended thermal batteries contain no lead or cadmium and do not represent a significant disposal or environmental problem. Thermal batteries have a thirty year history of excellent performance providing on-board power for missiles and other weapons and have a proven safety record with no field injuries ever. Thermal batteries have a relatively low cost of initial ownership and require no maintenance.

  13. Assessment of generic solar thermal systems for large power applications: analysis of electric power generating costs for systems larger than 10 MWe

    SciTech Connect

    Apley, W.J.; Bird, S.P.; Brown, D.R.; Drost, M.K.; Fort, J.A.; Garrett-Price, B.A.; Patton, W.P.; Williams, T.A.

    1980-11-01

    Seven generic types of collectors, together with associated subsystems for electric power generation, were considered. The collectors can be classified into three categories: (1) two-axis tracking (with compound-curvature reflecting surfaces); (2) one-axis tracking (with single-curvature reflecting surfaces); and (3) nontracking (with low-concentration reflecting surfaces). All seven collectors were analyzed in conceptual system configurations with Rankine-cycle engines. In addition, two of the collectors were analyzed with Brayton-cycle engines, and one was analyzed with a Stirling-cycle engine. With these engine options, and the consideration of both thermal and electrical storage for the Brayton-cycle central receiver, 11 systems were formulated for analysis. Conceptual designs developed for the 11 systems were based on common assumptions of available technology in the 1990 to 2000 time frame. No attempt was made to perform a detailed optimization of each conceptual design. Rather, designs best suited for a comparative evaluation of the concepts were formulated. Costs were estimated on the basis of identical assumptions, ground rules, methodologies, and unit costs of materials and labor applied uniformly to all of the concepts. The computer code SOLSTEP was used to analyze the thermodynamic performance characteristics and energy costs of the 11 concepts. Year-long simulations were performed using meteorological and insolation data for Barstow, California. Results for each concept include levelized energy costs and capacity factors for various combinations of storage capacity and collector field size.

  14. Water power generator

    Microsoft Academic Search

    Borgren

    1982-01-01

    A water power generator for generating electrical energy from a moving body of water comprising structural means interposed in the path of water flow. The structural means includes at least one side wall which is longitudinally curved from a diverting point at the outer end thereof to a gradually flattened curve at the inner end thereof. The wall is transversely

  15. Power-Generation Characteristics After Vibration and Thermal Stresses of Thermoelectric Unicouples with CoSb3/Ti/Mo(Cu) Interfaces

    NASA Astrophysics Data System (ADS)

    Bae, Kwang Ho; Choi, Soon-Mok; Kim, Kyung-Hun; Choi, Hyoung-Seuk; Seo, Won-Seon; Kim, Il-Ho; Lee, Soonil; Hwang, Hae Jin

    2015-06-01

    Reliability tests for thermoelectric unicouples were carried out to investigate the adhesion properties of CoSb3/Ti/Mo(Cu) interfaces. The n-type In0.25 Co3.95Ni0.05Sb12 and p-type In0.25Co3FeSb12 bulks were prepared for fabricating a thermoelectric unicouple (one p- n couple) by an induction melting and a spark plasma sintering process. Mo-Cu alloy was selected as an electrode for the unicouples due to its high melting temperature and proper work function value. Many thermoelectric unicouples with the CoSb3/Ti/Mo(Cu) interfaces were fabricated with the proper brazing materials by means of a repeated firing process. Reliability of the unicouples with the interfaces was evaluated by a vibration test and a thermal cycling test. After the thermal cycling and vibration tests, the power-generation characteristics of the unicouples were compared with the unicouples before the tests. Even after the vibration test, electrical power with a power density of 0.5 W/cm2 was generated. The Ti-interlayer is considered as a possible candidate for making a reliable unicouple with high adhesion strength. With the thermal cycling test, the resistance of the unicouple increased and the electrical power from the unicouple decreased. A failure mode by the thermal cycling test was ascribed to a complex effect of micro-cracks originated from the thermal stress and oxidation problem of the thermoelectric materials; that is, a thick oxide layer more than 300 ?m was detected after a high-temperature durability test of n-type In0.25Co3.95Ni0.05Sb12 material at 773 K in air for 7 days.

  16. JV Task 46 - Development and Testing of a Thermally Integrated SOFC-Gasification System for Biomass Power Generation

    SciTech Connect

    Phillip Hutton; Nikhil Patel; Kyle Martin; Devinder Singh

    2008-02-01

    The Energy & Environmental Research Center has designed a biomass power system using a solid oxide fuel cell (SOFC) thermally integrated with a downdraft gasifier. In this system, the high-temperature effluent from the SOFC enables the operation of a substoichiometric air downdraft gasifier at an elevated temperature (1000 C). At this temperature, moisture in the biomass acts as an essential carbon-gasifying medium, reducing the equivalence ratio at which the gasifier can operate with complete carbon conversion. Calculations show gross conversion efficiencies up to 45% (higher heating value) for biomass moisture levels up to 40% (wt basis). Experimental work on a bench-scale gasifier demonstrated increased tar cracking within the gasifier and increased energy density of the resultant syngas. A series of experiments on wood chips demonstrated tar output in the range of 9.9 and 234 mg/m{sup 3}. Both button cells and a 100-watt stack was tested on syngas from the gasifier. Both achieved steady-state operation with a 22% and 15% drop in performance, respectively, relative to pure hydrogen. In addition, tar tolerance testing on button cells demonstrated an upper limit of tar tolerance of approximately 1%, well above the tar output of the gasifier. The predicted system efficiency was revised down to 33% gross and 27% net system efficiency because of the results of the gasifier and fuel cell experiments. These results demonstrate the feasibility and benefits of thermally integrating a gasifier and a high-temperature fuel cell in small distributed power systems.

  17. Peak power ratio generator

    DOEpatents

    Moyer, Robert D. (Albuquerque, NM)

    1985-01-01

    A peak power ratio generator is described for measuring, in combination with a conventional power meter, the peak power level of extremely narrow pulses in the gigahertz radio frequency bands. The present invention in a preferred embodiment utilizes a tunnel diode and a back diode combination in a detector circuit as the only high speed elements. The high speed tunnel diode provides a bistable signal and serves as a memory device of the input pulses for the remaining, slower components. A hybrid digital and analog loop maintains the peak power level of a reference channel at a known amount. Thus, by measuring the average power levels of the reference signal and the source signal, the peak power level of the source signal can be determined.

  18. Environment friendly thermal power dispatch: An approach

    SciTech Connect

    Sen, S. [Power Grid Corp. of India, Ltd., New Delhi (India). Engineering Div.; Kothari, D.P.; Talukder, F.A. [Indian Inst. of Tech., New Delhi (India). Centre for Energy Studies

    1997-05-01

    This article describes an approach for optimal emission power dispatch from thermal power plants with optimal operating cost. The proposed approach, called economic-emission dispatch, is based on a {lambda}-iteration technique including penalty on emissions. Sample case studies with a system of three generating units are discussed.

  19. Integrating thermal energy storage in power plants

    SciTech Connect

    Somasundaram, S.; Drost, M.K.; Brown, D.R.; Antoniak, Z.I. (Pacific Northwest Lab., Richland, WA (United States))

    1993-09-01

    This article describes a system that stores thermal energy in a natural gas-fired cogeneration facility uses a gas turbine, a heat recovery salt heater, and salt-heated steam generator. The National Energy Strategy forecast estimates that 200,000 megawatts-electric (MWe) of new electric-generating capacity will need to be added to the US nationally by the year 2010. Approximately 40 percent of this new generating capacity will be for peak or intermediate loads, with the rest providing continuous baseload power generation. Natural gas-fired combustion turbine technologies, including cogeneration, combined-cycle, and integrated gasification combined-cycle power plants, are becoming the generating options of choice because of their flexibility, relatively low capital cost, reduced environmental impact, and increasing thermal efficiency. Thermal energy storage (TES) for utility applications includes a range of technologies that can further improve the efficiency, flexibility, and economics of gas turbine options.

  20. Microfabricated thermoelectric power-generation devices

    NASA Technical Reports Server (NTRS)

    Fleurial, Jean-Pierre (Inventor); Ryan, Margaret A. (Inventor); Borshchevsky, Alex (Inventor); Phillips, Wayne (Inventor); Kolawa, Elizabeth A. (Inventor); Snyder, G. Jeffrey (Inventor); Caillat, Thierry (Inventor); Kascich, Thorsten (Inventor); Mueller, Peter (Inventor)

    2004-01-01

    A device for generating power to run an electronic component. The device includes a heat-conducting substrate (composed, e.g., of diamond or another high thermal conductivity material) disposed in thermal contact with a high temperature region. During operation, heat flows from the high temperature region into the heat-conducting substrate, from which the heat flows into the electrical power generator. A thermoelectric material (e.g., a BiTe alloy-based film or other thermoelectric material) is placed in thermal contact with the heat-conducting substrate. A low temperature region is located on the side of the thermoelectric material opposite that of the high temperature region. The thermal gradient generates electrical power and drives an electrical component.

  1. Microfabricated thermoelectric power-generation devices

    NASA Technical Reports Server (NTRS)

    Fleurial, Jean-Pierre (Inventor); Ryan, Margaret A. (Inventor); Borshchevsky, Alex (Inventor); Phillips, Wayne (Inventor); Kolawa, Elizabeth A. (Inventor); Snyder, G. Jeffrey (Inventor); Caillat, Thierry (Inventor); Kascich, Thorsten (Inventor); Mueller, Peter (Inventor)

    2002-01-01

    A device for generating power to run an electronic component. The device includes a heat-conducting substrate (composed, e.g., of diamond or another high thermal conductivity material) disposed in thermal contact with a high temperature region. During operation, heat flows from the high temperature region into the heat-conducting substrate, from which the heat flows into the electrical power generator. A thermoelectric material (e.g., a BiTe alloy-based film or other thermoelectric material) is placed in thermal contact with the heat-conducting substrate. A low temperature region is located on the side of the thermoelectric material opposite that of the high temperature region. The thermal gradient generates electrical power and drives an electrical component.

  2. High power microwave generator

    DOEpatents

    Ekdahl, C.A.

    1983-12-29

    A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

  3. High power microwave generator

    DOEpatents

    Ekdahl, Carl A. (Albuquerque, NM)

    1986-01-01

    A microwave generator efficiently converts the energy of an intense relativistic electron beam (REB) into a high-power microwave emission using the Smith-Purcell effect which is related to Cerenkov radiation. Feedback for efficient beam bunching and high gain is obtained by placing a cylindrical Smith-Purcell transmission grating on the axis of a toroidal resonator. High efficiency results from the use of a thin cold annular highly-magnetized REB that is closely coupled to the resonant structure.

  4. Spectrophotovoltaic orbital power generation

    NASA Technical Reports Server (NTRS)

    Onffroy, J. R.

    1980-01-01

    The feasibilty of a spectrophotovoltaic orbital power generation system that optically concentrates solar energy is demonstrated. A dichroic beam-splitting mirror is used to divide the solar spectrum into two wavebands. Absorption of these wavebands by GaAs and Si solar cell arrays with matched energy bandgaps increases the cell efficiency while decreasing the amount of heat that must be rejected. The projected cost per peak watt if this system is $2.50/W sub p.

  5. COMPREHENSIVE STANDARDS: THE POWER GENERATION CASE

    EPA Science Inventory

    This study presents an illustrative data base of material quantities and environmental effluents in the fuel cycles for alternative technologies of thermally generated power. The entire fuel cycle for each of the alternative ten technologies is outlined for a representative power...

  6. Thermal properties of power HBT's

    Microsoft Academic Search

    J. Aiden Higgins

    1993-01-01

    Simulations of the thermal behavior of AlGaAs\\/GaAs HBT power transistors have been carried out to establish the quantitative tradeoff between power density, chip layout and junction temperatures. Numerical programs were used to model different aspects of HBT thermal behavior. These programs provide a dynamic solution for temperature distribution using a three-dimensional model which is very general in its ability to

  7. Small community solar thermal power experiment

    Microsoft Academic Search

    A. T. Marriott; T. Kiceniuk

    1980-01-01

    The first solar thermal power plant specifically designed as an alternate source of electric energy for small communities in this country is now in its second phase of development. As a result of Phase I concept definition studies, a decision was made to pursue a parabolic dish system using distributed generation. Both the design approach and the site selection status

  8. GEOTHERMAL POWER GENERATION PLANT

    SciTech Connect

    Boyd, Tonya

    2013-12-01

    Oregon Institute of Technology (OIT) drilled a deep geothermal well on campus (to 5,300 feet deep) which produced 196oF resource as part of the 2008 OIT Congressionally Directed Project. OIT will construct a geothermal power plant (estimated at 1.75 MWe gross output). The plant would provide 50 to 75 percent of the electricity demand on campus. Technical support for construction and operations will be provided by OIT’s Geo-Heat Center. The power plant will be housed adjacent to the existing heat exchange building on the south east corner of campus near the existing geothermal production wells used for heating campus. Cooling water will be supplied from the nearby cold water wells to a cooling tower or air cooling may be used, depending upon the type of plant selected. Using the flow obtained from the deep well, not only can energy be generated from the power plant, but the “waste” water will also be used to supplement space heating on campus. A pipeline will be construction from the well to the heat exchanger building, and then a discharge line will be construction around the east and north side of campus for anticipated use of the “waste” water by facilities in an adjacent sustainable energy park. An injection well will need to be drilled to handle the flow, as the campus existing injection wells are limited in capacity.

  9. Power generation, operation, and control

    Microsoft Academic Search

    A. J. Wood; B. F. Wollenberg

    1984-01-01

    This book discusses the economic and engineering aspects used in the planning, operating, and controlling of power generation and transmission systems for electric utilities. It presents advanced mathematical and operations research methods used for electric power engineering problems. It covers methods currently applied in the control and operation of electric power systems. The contents are characteristics of power generation units.

  10. Thermal control system for Space Station Freedom photovoltaic power module

    Microsoft Academic Search

    Thomas H. Hacha; Laura S. Howard

    1992-01-01

    The electric power for Space Station Freedom (SSF) is generated by the solar arrays of the photovoltaic power modules (PVM's) and conditioned, controlled, and distributed by a power management and distribution system. The PVM's are located outboard of the alpha gimbals of SSF. A single-phase thermal control system is being developed to provide thermal control of PVM electrical equipment and

  11. Thermal control system for Space Station Freedom photovoltaic power module

    Microsoft Academic Search

    Thomas H. Hacha; Laura Howard

    1994-01-01

    The electric power for Space Station Freedom (SSF) is generated by the solar arrays of the photovoltaic power modules (PVM's) and conditioned, controlled, and distributed by a power management and distribution system. The PVM's are located outboard of the alpha gimbals of SSF. A single-phase thermal control system is being developed to provide thermal control of PVM electrical equipment and

  12. Thermal Sciences The thermal sciences area involves the study of energy conversion and transmission, power

    E-print Network

    New Hampshire, University of

    Thermal Sciences The thermal sciences area involves the study of energy conversion and transmission, power generation, the flow of liquids and gases, and the transfer of thermal energy (heat) by means and an airplane can be propelled forward. The processes involved are a superb example of thermal science processes

  13. Power generating apparatus

    SciTech Connect

    Vukovic, M.

    1981-02-10

    Power generating apparatus comprising a float mounted on a support which is pivotally mounted to a base the support being secured to a beam extending rearwardly of the base to a vertically extending elongated structure carrying a pair of vertically moveable gear racks in guideways. Each rack is engaged by a gear wheel driven by movement of the racks and one-way drive means connects each gear wheel to an output shaft. Driving weights are secured to each rack to drive the racks in opposite directions under the action of gravity forces acting on the weights, the driving motion causing the output shaft to rotate in a given direction. The free end of the beam is connected to a cross-arm vertically moveable on a guide on the elongate structure, the cross-arm having motion transmitting means to raise each of the weights during vertical movement of the crossarm resulting from movement of the float.

  14. Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

    2014-01-01

    This presentation describes the capabilities of three-dimensional thermal power model of advanced stirling radioisotope generator (ASRG). The performance of the ASRG is presented for different scenario, such as Venus flyby with or without the auxiliary cooling system.

  15. Next Generation Geothermal Power Plants

    Microsoft Academic Search

    John Brugman; Mai Hattar; Kenneth Nichols; Yuri Esaki

    1995-01-01

    A number of current and prospective power plant concepts were investigated to evaluate their potential to serve as the basis of the next generation geothermal power plant (NGGPP). The NGGPP has been envisaged as a power plant that would be more cost competitive (than current geothermal power plants) with fossil fuel power plants, would efficiently use resources and mitigate the

  16. Solar Thermal Power Stations

    Microsoft Academic Search

    Bernhard Milow; Franz Trieb

    2000-01-01

    ABSTRACT Today we know,that not the resources of energy carriers will limit the fossil electricity generation in the next few decades. But global warming,and the rapid growth of the world population are forcing us to urgently develop alternatives. By the end of the21 ,century when,special conditions in California allowed to compete with fossil energy systems and its very low fuel

  17. Dynamic power systems for power generation

    NASA Astrophysics Data System (ADS)

    English, R. E.

    1984-04-01

    The characteristics of dynamic power systems have considerable potential value, especially for the space station. The base of technology that makes these dynamic power systems practical is reviewed. The following types of power-generating systems are examined herein: organic Rankine cycle, potassium Rankine cycle, Brayton cycle, and Stirling cycle.

  18. Simulation and economic analysis of a CPV\\/thermal system coupled with an organic Rankine cycle for increased power generation

    Microsoft Academic Search

    G. Kosmadakis; D. Manolakos; G. Papadakis

    2011-01-01

    In concentrating photovoltaic (CPV) systems the incident solar radiation is multiplied by a factor equal to the concentration ratio, with the use of lenses or reflectors. This is implemented, in order to increase the electric power production, since this value has a linear dependence from the incident radiation. Therefore, the specific energy production of the cells (kWh\\/m2) radically increases, but

  19. Automotive Power Generation and Control

    E-print Network

    Caliskan, Vahe

    This paper describes some new developments in the application of power electronics to automotive power generation and control. A new load-matching technique is introduced that uses a simple switched-mode rectifier to achieve ...

  20. Achieving Maximum Power in Thermoelectric Generation with Simple Power Electronics

    NASA Astrophysics Data System (ADS)

    Youn, Nari; Lee, Hohyun; Wee, Daehyun; Gomez, Miguel; Reid, Rachel; Ohara, Brandon

    2014-06-01

    A thermoelectric generator typically delivers a relatively low power output, and hence it is of great practical importance to determine a design and operating condition close to those which can provide the maximum attainable power. To maintain a favorable condition for the maximum power output, power electronics circuits are usually applied. One of the simplest methods is to control the operating voltage at half the open-circuit voltage, assuming that the typical impedance-matching condition, in which the load and internal resistances are matched, yields the maximum power output. However, recent investigations have shown that, when external thermal resistances exist between the thermoelectric modules and thermal reservoirs, the impedance-matching condition is not identical to the condition for the maximum power output. In this article, it is argued that, although the impedance-matching condition is not the condition for maximum power output, the maximum power is still achievable when the operating voltage is kept at half the open-circuit voltage. More precisely, it is shown that the typical V- I curve for thermoelectric generators must show approximately linear behavior, which justifies the use of a simple strategy in thermoelectric power generation applications. The conditions for the validity of the approximation are mathematically discussed, supported by a few examples. Experimental evidence at room temperature is also provided.

  1. Optimal Operating Temperature for Solar Thermal Power System

    Microsoft Academic Search

    Lu Jianfeng; Ding Jing

    2009-01-01

    Solar thermal power is currently one of the important trends and research hotspots of solar energy. In present paper, basic physical model is proposed to investigate the solar thermal power, and the operating temperature is optimized to maximize the electricity generating efficiency. As the incident energy flux rises, the wall temperature almost linearity increases, while the heat absorption efficiency will

  2. A parametric study of solar thermal power plant

    Microsoft Academic Search

    A. A. Samuel; K. A. Bhaskaran; M. C. Gupta

    1979-01-01

    The solar thermal power plant discussed in this paper consists of four subsystems: collector system, storage system, prime mover, and generator. The paper considers a Rankine cycle engine which has high thermal efficiency, relatively simple mechanical components and acceptability for use over a wide range of powers. Three working fluids (butane, F113 and F114) are selected because of their low

  3. Thermally matched fluid cooled power converter

    DOEpatents

    Radosevich, Lawrence D.; Kannenberg, Daniel G.; Kaishian, Steven C.; Beihoff, Bruce C.

    2005-06-21

    A thermal support may receive one or more power electronic circuits. The support may aid in removing heat from the circuits through fluid circulating through the support. Power electronic circuits are thermally matched, such as between component layers and between the circuits and the support. The support may form a shield from both external EMI/RFI and from interference generated by operation of the power electronic circuits. Features may be provided to permit and enhance connection of the circuitry to external circuitry, such as improved terminal configurations. Modular units may be assembled that may be coupled to electronic circuitry via plug-in arrangements or through interface with a backplane or similar mounting and interconnecting structures.

  4. Power generating method and apparatus

    Microsoft Academic Search

    Chih-kang

    1980-01-01

    A description is given of a method of power generation comprising performing a working cycle on a refrigerant used as a working medium and utilizing said refrigerant to drive a turbine operating a power generator, said cycle including the steps of: providing a source of refrigerant in a compressed liquid phase; heating said source by immersion in a tank of

  5. Independent power generator

    NASA Technical Reports Server (NTRS)

    Young, R. N. (inventor)

    1978-01-01

    A gas turbine powered aircraft auxiliary power system is described which is capable of efficiently supplying all aircraft auxiliary services both in flight and on the ground and is further capable of operating independently of the aircraft main engines. The system employs multiple gas turbine compressor stages, thereby accomplishing cabin pressurization, ventilation and heating.

  6. Independent power generator

    Microsoft Academic Search

    R. N. Young

    1978-01-01

    A gas turbine powered aircraft auxiliary power system is described which is capable of efficiently supplying all aircraft auxiliary services both in flight and on the ground and is further capable of operating independently of the aircraft main engines. The system employs multiple gas turbine compressor stages, thereby accomplishing cabin pressurization, ventilation and heating. Bibtex entry for this abstract Preferred

  7. Automotive power generation and control

    Microsoft Academic Search

    David J. Perreault; Vahe Caliskan

    2004-01-01

    This paper describes some new developments in the application of power electronics to automotive power generation and control. A new load-matching technique is introduced that uses a simple switched-mode rectifier to achieve dramatic increases in peak and average power output from a conventional Lundell alternator, along with substantial improvements in efficiency. Experimental results demonstrate these capability improvements. Additional performance and

  8. Mesofluidic magnetohydrodynamic power generation

    E-print Network

    Fucetola, Jay J

    2012-01-01

    Much of the previous research into magnetohydrodynamics has involved large-scale systems. This thesis explores the miniaturization and use of devices to convert the power dissipated within an expanding gas flow into ...

  9. An Isotope-Powered Thermal Storage unit for space applications

    NASA Technical Reports Server (NTRS)

    Lisano, Michael E.; Rose, M. F.

    1991-01-01

    An Isotope-Powered Thermal Storage Unit (ITSU), that would store and utilize heat energy in a 'pulsed' fashion in space operations, is described. Properties of various radioisotopes are considered in conjunction with characteristics of thermal energy storage materials, to evaluate possible implementation of such a device. The utility of the unit is discussed in light of various space applications, including rocket propulsion, power generation, and spacecraft thermal management.

  10. Autonomous Underwater Vehicle Thermoelectric Power Generation

    NASA Astrophysics Data System (ADS)

    Buckle, J. R.; Knox, A.; Siviter, J.; Montecucco, A.

    2013-07-01

    Autonomous underwater vehicles (AUVs) are a vital part of the oceanographer's toolbox, allowing long-term measurements across a range of ocean depths of a number of ocean properties such as salinity, fluorescence, and temperature profile. Buoyancy-based gliding, rather than direct propulsion, dramatically reduces AUV power consumption and allows long-duration missions on the order of months rather than hours or days, allowing large distances to be analyzed or many successive analyses of a certain area without the need for retrieval. Recent versions of these gliders have seen the buoyancy variation system change from electrically powered to thermally powered using phase-change materials, however a significant battery pack is still required to power communications and sensors, with power consumption in the region of 250 mW. The authors propose a novel application of a thermoelectric generation system, utilizing the depth-related variation in oceanic temperature. A thermal energy store provides a temperature differential across which a thermoelectric device can generate from repeated dives, with the primary purpose of extending mission range. The system is modeled in Simulink to analyze the effect of variation in design parameters. The system proves capable of generating all required power for a modern AUV.

  11. Infrared power generation in an insulated environment

    NASA Astrophysics Data System (ADS)

    Schwab, Yosyp; Mann, Harkirat; Lang, Brian; Lancaster, Jarrett; Parise, Ronald; Vincent-Johnson, Anita; Scarel, Giovanna

    2014-03-01

    Alternative energy sources are an increasingly popular field of research, in particular energy harvesting through solar radiation, focusing on infrared (IR) radiation. Exploitation of readily available thermal energy is particularly interesting due to possible widespread applications. This work examines the behavior of thermoelectric devices exposed to infrared radiation in a controlled environment. Thermoelectric power generators work according to the Seebeck effect, where the temperature difference ?V induced between the two junctions is linearly proportional to the voltage difference ?T across the two contacts. Our experimental results show that heat and radiation do not activate the same mechanisms in the thermoelectric power generator. Analysis and simulation further support the distinction between the IR and heat power generation. In particular, ?T and ?V have a linear and exponential behavior versus time with heat and IR, respectively. Our work is of significant importance for designing IR sensors, detectors, and radiation harvesting devices.

  12. Tide operated power generating apparatus

    SciTech Connect

    Kertzman, H. Z.

    1981-02-03

    An improved tide operated power generating apparatus is disclosed in which a hollow float, rising and falling with the ocean tide, transmits energy to a power generator. The improvement comprises means for filling the float with water during the incoming tide to provide a substantial increase in the float dead weight during the outgoing tide. Means are further provided to then empty the float before the outgoing tide whereby the float becomes free to rise again on the next incoming tide.

  13. Spin Seebeck power generators

    SciTech Connect

    Cahaya, Adam B.; Tretiakov, O. A. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Bauer, Gerrit E. W. [Institute for Materials Research and WPI-AIMR, Tohoku University, Sendai 980-8577 (Japan); Kavli Institute of NanoScience, TU Delft Lorentzweg 1, 2628 CJ Delft (Netherlands)

    2014-01-27

    We derive expressions for the efficiency and figure of merit of two spin caloritronic devices based on the spin Seebeck effect (SSE), i.e., the generation of spin currents by a temperature gradient. The inverse spin Hall effect is conventionally used to detect the SSE and offers advantages for large area applications. We also propose a device that converts spin current into electric one by means of a spin-valve detector, which scales favorably to small sizes and approaches a figure of merit of 0.5 at room temperature.

  14. Thermoelectric power generation in a thermoacoustic refrigerator

    Microsoft Academic Search

    W. V. Slaton; J. C. H. Zeegers

    2006-01-01

    Commercially available solid-state thermoelectric devices may be used for their electrical power generation capabilities when coupled to a thermoacoustic refrigerator or heat pump. General performance characteristics as well as bulk thermal conductivity for a selection of thermoelectric elements was first found by using a two-plate apparatus to maintain a constant temperature difference across the element. Further studies of an element’s

  15. Optimal working conditions for thermoelectric generators with realistic thermal coupling

    E-print Network

    Apertet, Y; Glavatskaya, O; Goupil, C; Lecoeur, P

    2011-01-01

    We study how maximum output power can be obtained from a thermoelectric generator(TEG) with nonideal heat exchangers. We demonstrate with an analytic approach based on a force-flux formalism that the sole improvement of the intrinsic characteristics of thermoelectric modules including the enhancement of the figure of merit is of limited interest: the constraints imposed by the working conditions of the TEG must be considered on the same footing. Introducing an effective thermal conductance we derive the conditions which permit maximization of both efficiency and power production of the TEG dissipatively coupled to heat reservoirs. Thermal impedance matching must be accounted for as well as electrical impedance matching in order to maximize the output power. Our calculations also show that the thermal impedance does not only depend on the thermal conductivity at zero electrical current: it also depends on the TEG figure of merit. Our analysis thus yields both electrical and thermal conditions permitting optima...

  16. Photovoltaic power generation: A review

    Microsoft Academic Search

    S. Mahdi Moosavian; N. Abd Rahim; Jeyraj Selvaraj

    2011-01-01

    Renewable power generation's increased importance is owed to increased population and pollution concerns, global warming, and need for new energy resources. Solar energy is a completely clean energy resource and can be used almost anywhere; its application the focus of most research on it. Photovoltaic generation systems are reviewed here, in single-resource implementation and in various hybrid systems, and related

  17. Chemical energy storage system for SEGS solar thermal power plant

    Microsoft Academic Search

    D. R. Brown; J. L. Lamarche; G. E. Spanner

    1991-01-01

    In October 1988, a symposium was held in Helendale, California, to discuss thermal energy storage (TES) concepts applicable to medium temperature (200 to 400 C) solar thermal electric power plants, in general, and the solar electric generating system (SEGS) plants developed by Luz International, in particular. Chemical reaction energy storage based on the reversible reaction between metal oxides and metal

  18. Active thermal control of power electronic modules

    Microsoft Academic Search

    Dustin A. Murdock; Jose E. Ramos Torres; Jeffrey J. Connors; Robert D. Lorenz

    2006-01-01

    Active thermal control techniques make it feasible to regulate the steady state and transient thermal-mechanical stress in power electronic modules for applications such as motor drives. Online junction temperature estimation and manipulation of the switching frequency and current limit to regulate the losses are used to prevent overtemperature and power cycling failures in insulated gate bipolar transistor (IGBT) power modules.

  19. Kinetics of thermal donor generation in silicon

    NASA Technical Reports Server (NTRS)

    Mao, B.-Y.; Lagowski, J.; Gatos, H. C.

    1984-01-01

    The generation kinetics of thermal donors at 450 C in Czochralski-grown silicon was found to be altered by high-temperature preannealing (e.g., 1100 C for 30 min). Thus, when compared with as-grown Si, high-temperature preannealed material exhibits a smaller concentration of generated thermal donors and a faster thermal donor saturation. A unified mechanism of nucleation and oxygen diffusion-controlled growth (based on solid-state plate transformation theory) is proposed to account for generation kinetics of thermal donors at 450 C, in as-grown and high-temperature preannealed Czochralski silicon crystals. This mechanism is consistent with the main features of the models which have been proposed to explain the formation of oxygen thermal donors in silicon.

  20. Entropy generation method to quantify thermal comfort

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

  1. Heat generating compositions for thermal batteries

    NASA Astrophysics Data System (ADS)

    Sheptunov, V. N.

    1991-03-01

    Thermal batteries are widely used as independent current sources with long storage life and the ability to operate over a wide ambient temperature range. A number of pyrotechnic materials may as rule be used as sources of thermal energy to provide ionic conduction in a molten electrolyte and to maintain the working temperature of the battery during the discharge of the electrochemical elements. The requirements for heat sources in thermal batteries are described and different heat generating compositions are reviewed.

  2. Thermal stress computation for steam-electric generator dispatch

    SciTech Connect

    Delson, J.K. (Applied Analytics Associates, Palo Alto, CA (United States))

    1994-02-01

    Calculation of thermal stress in loading and unloading steam-electric generators can permit dispatch at higher ramp rates without increasing turbine rotor fatigue. The calculations are made from a thermal model of the rotor that does not require temperature sensors. The equations are validated against the fatigue index curves provided by turbine manufacturers. Examples are presented to show the advantage of using this model for dispatch and for the retrospective analysis of power output records.

  3. Solid state pulsed power generator

    DOEpatents

    Tao, Fengfeng; Saddoughi, Seyed Gholamali; Herbon, John Thomas

    2014-02-11

    A power generator includes one or more full bridge inverter modules coupled to a semiconductor opening switch (SOS) through an inductive resonant branch. Each module includes a plurality of switches that are switched in a fashion causing the one or more full bridge inverter modules to drive the semiconductor opening switch SOS through the resonant circuit to generate pulses to a load connected in parallel with the SOS.

  4. A dish-Stirling solar-thermal power system

    Microsoft Academic Search

    R. L. Pons; T. B. Clark

    1980-01-01

    This paper presents results of a preliminary design\\/economic study of a first-generation point focusing distributed receiver solar-thermal electric system optimized for application to industrial and small community power plants at power levels up to 10 MWe. Power conversion is provided by small Stirling cycle engines mounted at the focus of paraboloidal solar concentrators. The output of multiple power modules (concentrator,

  5. Assessment of solar thermal concepts for small power systems applications

    Microsoft Academic Search

    W. W. Laity; D. T. Aase; W. J. Apley; S. P. Bird; J. W. Currie; M. K. Drost; T. A. Williams

    1980-01-01

    The paper discusses a comparative analysis of ten solar thermal conversion concepts that are potentially suitable for development as small electric power systems (1-10 MWe). Seven generic types of collectors, together with associated subsystems for electric power generation, were considered. All seven collectors were analyzed in conceptual systems with Rankine-cycle engines. In addition, two of the collectors with particularly high

  6. Performance evaluation and simulation of a solar thermal power plant

    Microsoft Academic Search

    Eduardo I. Ortiz-Rivera; Luisa I. Feliciano-Cruz

    2009-01-01

    This paper presents a Simulinkreg Model that has been developed for the performance evaluation and simulation of Solar Power Generating or Solar Thermal Power Plants in Puerto Rico with the Compound Parabolic Concentrator as the solar collector of choice. There are several costly and sophisticated commercial software programs that perform this task but, this tool is aimed at performing initial

  7. Application possibilities of solar thermal power plants in Arab countries

    Microsoft Academic Search

    Omar H. Al-Sakaf

    1998-01-01

    Many international studies and experience have shown that solar thermal power plants are the most economic form of the solar electricity generation. Since such plants are based on the concentration of the solar radiation to achieve high temperatures necessary for the thermo-dynamic power plant process, their application area is restricted to earth regions with high direct solar radiation. Arab countries

  8. GREENHOUSE GAS ANALYSIS OF SOLAR-THERMAL ELECTRICITY GENERATION

    Microsoft Academic Search

    M. LENZEN

    1999-01-01

    Solar-thermal electricity generation contributes to climate change because it incurs the emission of greenhouse gases during the provision of services and the production of materials needed for the construction and operation of solar power plants. These greenhouse gas costs (GGC) can be determined using either material inventories in physical units or monetary cost breakdowns. Solar-only plants employing parabolic troughs, central

  9. Advanced LMMHD space power generation concept

    Microsoft Academic Search

    Vincent Ho; Albert Wong; Kilyoo Kim; Vijay Dhir

    1987-01-01

    Magnetohydrodynamic (MHD) power generation concept has been proposed and studied worldwide as one of the future power generation sources. An advanced one fluid two phase liquid metal (LM) MHD power generation concept was developed for space nuclear power generation design. The concept employs a nozzle to accelerate the liquid metal coolant to an acceptable velocity with Mach number greater than

  10. Unified model of solar thermal electric generation systems

    Microsoft Academic Search

    Saad D. Odeh

    2003-01-01

    In this paper a unified model of a solar electric generation system (SEGS) is developed using a thermo-hydrodynamic model of a trough collector combined with a model of a traditional steam power-house. The model evaluates thermal properties, steam flow rate and pressure drop in a direct steam generation (DSG) or an oil based collector field. The SEGS’s performance in different

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

    Microsoft Academic Search

    A. Marriott

    1980-01-01

    The activities of the Point-Focusing Thermal and Electric Applications (PETEA) project for the fiscal year 1979 are summarized. The main thrust of the PFTEA Project, the small community solar thermal power experiment, was completed. Concept definition studies included a small central receiver approach, a point-focusing distributed receiver system with central power generation, and a point-focusing distributed receiver concept with distributed

  12. Storage systems for solar thermal power

    NASA Technical Reports Server (NTRS)

    Calogeras, J. E.; Gordon, L. H.

    1978-01-01

    A major constraint to the evolution of solar thermal power systems is the need to provide continuous operation during periods of solar outage. A number of high temperature thermal energy storage technologies which have the potential to meet this need are currently under development. The development status is reviewed of some thermal energy storage technologies specifically oriented towards providing diurnal heat storage for solar central power systems and solar total energy systems. These technologies include sensible heat storage in caverns and latent heat storage using both active and passive heat exchange processes. In addition, selected thermal storage concepts which appear promising to a variety of advanced solar thermal system applications are discussed.

  13. Solar thermal power plant - Thermodynamic analysis

    Microsoft Academic Search

    A. A. Samuel; M. C. Gupta

    1980-01-01

    There have been several proposals for solar thermal power plants using a Rankine cycle with a low boiling point fluid as the working medium. Organic Rankine-cycle engines are particularly suited for a number of reasons such as, high thermal efficiency and reliability, relatively uncomplicated mechanical components and adaptability for use over a wide power range. In this study three working

  14. Thermal buffering of receivers for parabolic dish solar thermal power plants

    Microsoft Academic Search

    R. Manvi; T. Fujita; B. C. Gajanana; C. J. Marcus

    1980-01-01

    A parabolic dish solar thermal power plant comprises a field of parabolic dish power modules where each module is composed of a two-axis tracking parabolic dish concentrator which reflects sunlight (insolation) into the aperture of a cavity receiver at the focal point of the dish. The heat generated by the solar flux entering the receiver is removed by a heat

  15. Next Generation Geothermal Power Plants

    SciTech Connect

    Brugman, John; Hattar, Mai; Nichols, Kenneth; Esaki, Yuri

    1995-09-01

    A number of current and prospective power plant concepts were investigated to evaluate their potential to serve as the basis of the next generation geothermal power plant (NGGPP). The NGGPP has been envisaged as a power plant that would be more cost competitive (than current geothermal power plants) with fossil fuel power plants, would efficiently use resources and mitigate the risk of reservoir under-performance, and minimize or eliminate emission of pollutants and consumption of surface and ground water. Power plant concepts were analyzed using resource characteristics at ten different geothermal sites located in the western United States. Concepts were developed into viable power plant processes, capital costs were estimated and levelized busbar costs determined. Thus, the study results should be considered as useful indicators of the commercial viability of the various power plants concepts that were investigated. Broadly, the different power plant concepts that were analyzed in this study fall into the following categories: commercial binary and flash plants, advanced binary plants, advanced flash plants, flash/binary hybrid plants, and fossil/geothed hybrid plants. Commercial binary plants were evaluated using commercial isobutane as a working fluid; both air-cooling and water-cooling were considered. Advanced binary concepts included cycles using synchronous turbine-generators, cycles with metastable expansion, and cycles utilizing mixtures as working fluids. Dual flash steam plants were used as the model for the commercial flash cycle. The following advanced flash concepts were examined: dual flash with rotary separator turbine, dual flash with steam reheater, dual flash with hot water turbine, and subatmospheric flash. Both dual flash and binary cycles were combined with other cycles to develop a number of hybrid cycles: dual flash binary bottoming cycle, dual flash backpressure turbine binary cycle, dual flash gas turbine cycle, and binary gas turbine cycle. Results of this study indicate that dual flash type plants are preferred at resources with temperatures above 400 F. Closed loop (binary type) plants are preferred at resources with temperatures below 400 F. A rotary separator turbine upstream of a dual flash plant can be beneficial at Salton Sea, the hottest resource, or at high temperature resources where there is a significant variance in wellhead pressures from well to well. Full scale demonstration is required to verify cost and performance. Hot water turbines that recover energy from the spent brine in a dual flash cycle improve that cycle's brine efficiency. Prototype field tests of this technology have established its technical feasibility. If natural gas prices remain low, a combustion turbine/binary hybrid is an economic option for the lowest temperature sites. The use of mixed fluids appear to be an attractive low risk option. The synchronous turbine option as prepared by Barber-Nichols is attractive but requires a pilot test to prove cost and performance. Dual flash binary bottoming cycles appear promising provided that scaling of the brine/working fluid exchangers is controllable. Metastable expansion, reheater, Subatmospheric flash, dual flash backpressure turbine, and hot dry rock concepts do not seem to offer any cost advantage over the baseline technologies. If implemented, the next generation geothermal power plant concept may improve brine utilization but is unlikely to reduce the cost of power generation by much more than 10%. Colder resources will benefit more from the development of a next generation geothermal power plant than will hotter resources. All values presented in this study for plant cost and for busbar cost of power are relative numbers intended to allow an objective and meaningful comparison of technologies. The goal of this study is to assess various technologies on an common basis and, secondarily, to give an approximate idea of the current costs of the technologies at actual resource sites. Absolute costs at a given site will be determined by the specifics of a given pr

  16. Solar energy power generation system

    SciTech Connect

    Nilsson, J.E.; Cochran, C.D.

    1986-05-06

    A solar energy power generation system is described which consists of: (a) means for collecting and concentrating solar energy; (b) heat storage means; (c) Stirling engine means for producing power; (d) first heat transfer means for receiving the concentrated solar energy and for transferring heat to the heat storage means; and (e) second heat transfer means for controllably transferring heat from the storage means to the Stirling engine means and including a discharge heat pipe means for transferring heat to the Stirling engine means and further including means for inserting and withdrawing the discharge heat pipe means into and out of the heat storage means.

  17. Local control of reactive power by distributed photovoltaic generators

    SciTech Connect

    Chertkov, Michael [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory; Sulc, Petr [Los Alamos National Laboratory; Backhaus, Scott [Los Alamos National Laboratory

    2010-01-01

    High penetration levels of distributed photovoltaic (PV) generation on an electrical distribution circuit may severely degrade power quality due to voltage sags and swells caused by rapidly varying PV generation during cloud transients coupled with the slow response of existing utility compensation and regulation equipment. Although not permitted under current standards for interconnection of distributed generation, fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage regulation under difficult transient conditions. As side benefit, the control of reactive power injection at each PV inverter provides an opportunity and a new tool for distribution utilities to optimize the performance of distribution circuits, e.g. by minimizing thermal losses. We suggest a local control scheme that dispatches reactive power from each PV inverter based on local instantaneous measurements of the real and reactive components of the consumed power and the real power generated by the PVs. Using one adjustable parameter per circuit, we balance the requirements on power quality and desire to minimize thermal losses. Numerical analysis of two exemplary systems, with comparable total PV generation albeit a different spatial distribution, show how to adjust the optimization parameter depending on the goal. Overall, this local scheme shows excellent performance; it's capable of guaranteeing acceptable power quality and achieving significant saving in thermal losses in various situations even when the renewable generation in excess of the circuit own load, i.e. feeding power back to the higher-level system.

  18. Solar-powered aroma generator

    SciTech Connect

    Spector, D.

    1986-02-04

    In combination with a switch-controlled electric light bulb having a threaded plug and a threaded socket disposed in a room which is also subject to natural ambient light, a switchless aroma generator is installed in the room which is automatically activated only when the electric light bulb is switched on. The activated generator functions to discharge an air current into the room which conveys an aromatic vapor to modify the atmosphere. The generator described in this patent consists of: A.) an air-permeable cartridge containing an aroma supply which is exuded into the atmosphere at a relatively rapid rate as an air current is forced through the cartridge; B.) a fan driven by a low-voltage, direct-current motor having predetermined power requirements, the fan being arranged to force an air current through the cartridge; C.) a housing incorporating the cartridge and the motordriven fan, the housing containing an apparatus for mounting it on a wall in the room; and D.) a solar cell assembly producing a direct-current output placed in close proximity to the bulb in the room and irradiated when the bulb is switched on. The assembly is connected to the motor to supply power, the electrical relationship of the assembly to the motor being such that the cell output is sufficient to power the motor only when the bulb is switched on to irradiate the assembly, and is insufficient when the bulb is switched off. The cell output then depends on ambient light in the room, and the operation of the generator is coordinated with that of the bulb despite the absence of a wired connection between and an aroma is generated only when the bulb is switched on.

  19. Active thermal control of power electronics modules

    Microsoft Academic Search

    D. A. Murdock; J. E. Ramos; J. J. Connors; R. D. Lorenz

    2003-01-01

    Active thermal control techniques make it feasible to regulate the steady state and transient thermal-mechanical stress in power electronic modules for applications such as motor drives. On-line junction temperature estimation and manipulation of the switching frequency and current limit to regulate the losses, are used to prevent over-temperature and power cycling failures in IGBT power modules. The techniques developed in

  20. Review of selected on-site DOE small solar thermal power plant experiments

    Microsoft Academic Search

    R. L. Alvis

    1979-01-01

    Three solar power plants are reviewed that were developed in an effort to find an alternate energy source for powering irrigation pumps. Power generation by the conversion of solar energy is shown to be technically feasible in the construction and operation of these three solar thermal power systems. The thermal cycling inherent in solar energy is shown to be more

  1. Central receiver solar thermal power system, Phase 1. CDRL item 2. Pilot plant preliminary design report. Volume VI. Electrical power generation and master control subsystems and balance of plant

    Microsoft Academic Search

    R. W. Jr. Hallet; R. L. Gervais

    1977-01-01

    The requirements, performance, and subsystem configuration for both the Commercial and Pilot Plant electrical power generation subsystems (EPGS) and balance of plants are presented. The EPGS for both the Commercial Plant and Pilot Plant make use of conventional, proven equipment consistent with good power plant design practices in order to minimize risk and maximize reliability. The basic EPGS cycle selected

  2. Advanced LMMHD space power generation concept

    NASA Astrophysics Data System (ADS)

    Ho, Vincent; Wong, Albert; Kim, Kilyoo; Dhir, Vijay

    Magnetohydrodynamic (MHD) power generation concept has been proposed and studied worldwide as one of the future power generation sources. An advanced one fluid two phase liquid metal (LM) MHD power generation concept was developed for space nuclear power generation design. The concept employs a nozzle to accelerate the liquid metal coolant to an acceptable velocity with Mach number greater than unity. Such nozzle and the MHD power generator replace the turbogenerator of a high temperature Rankine turboelectric cycle concept. As a result, the power generation system contains no movable parts. This provides high reliability, which is a very important factor in space application.

  3. A COMBUSTION-BASED MEMS THERMOELECTRIC POWER GENERATOR

    Microsoft Academic Search

    Samuel B. Schaevitz; Aleksander J. Franz; Klavs F. Jensen; Martin A. Schmidt

    2001-01-01

    SUMMARY A thermoelectric generator with integrated catalytic combustion has been microfabricated and successfully tested. The device consists of a high-temperature silicon-germanium thermopile supported on a thermally insulating silicon nitride membrane. Heat is supplied by catalytic combustion of fuels on the underside of the membrane. Power output has been generated from on- chip autothermal combustion of hydrogen, ammonia and butane, with

  4. Solar thermal power today and tomorrow

    SciTech Connect

    Mancini, T.R.; Chavez, J.M.; Kolb, G.J. (Sandia National Labs., Albuquerque, NM (United States). Solar Thermal Technology Dept.)

    1994-08-01

    This article is a look at the status of solar thermal power plant design and application. The topics of the article include US DOE involvement, trough-electric systems as a current alternative to conventional electric power production, and central receiver systems and dish/Stirling systems as alternatives to fossil-fuel power plants within the next five years.

  5. Future Photovoltaic Power Generation for Space-Based Power Utilities

    Microsoft Academic Search

    S. Bailey; G. Landis; R. Raffaelle; A. Hepp

    2002-01-01

    A recent NASA program, Space Solar Power Exploratory Research and Technology (SERT), investigated the technologies needed to provide cost-competitive ground baseload electrical power from space based solar energy conversion. This goal mandated low cost, light weight gigawatt (GW) power generation. Investment in solar power generation technologies would also benefit high power military, commercial and science missions. These missions are generally

  6. Power Generation: The Next 30 Years

    ERIC Educational Resources Information Center

    Holcomb, Robert W.

    1970-01-01

    Discusses pollution problems associated with power production. Estimates power consumption in the 1980's and the availability of fossil and nuclear fuel resources. Emphasizes needed research on air pollution, nuclear pollution, and thermal pollution. (EB)

  7. Thermoelectric cooling and power generation

    PubMed

    DiSalvo

    1999-07-30

    In a typical thermoelectric device, a junction is formed from two different conducting materials, one containing positive charge carriers (holes) and the other negative charge carriers (electrons). When an electric current is passed in the appropriate direction through the junction, both types of charge carriers move away from the junction and convey heat away, thus cooling the junction. Similarly, a heat source at the junction causes carriers to flow away from the junction, making an electrical generator. Such devices have the advantage of containing no moving parts, but low efficiencies have limited their use to specialty applications, such as cooling laser diodes. The principles of thermoelectric devices are reviewed and strategies for increasing the efficiency of novel materials are explored. Improved materials would not only help to cool advanced electronics but could also provide energy benefits in refrigeration and when using waste heat to generate electrical power. PMID:10426986

  8. Parabolic Trough Solar Thermal Electric Power Plants

    SciTech Connect

    Not Available

    2003-06-01

    Although many solar technologies have been demonstrated, parabolic trough solar thermal electric power plant technology represents one of the major renewable energy success stories of the last two decades.

  9. Storage systems for solar thermal power

    NASA Technical Reports Server (NTRS)

    Calogeras, J. E.; Gordon, L. H.

    1978-01-01

    The development status is reviewed of some thermal energy storage technologies specifically oriented towards providing diurnal heat storage for solar central power systems and solar total energy systems. These technologies include sensible heat storage in caverns and latent heat storage using both active and passive heat exchange processes. In addition, selected thermal storage concepts which appear promising to a variety of advanced solar thermal system applications are discussed.

  10. Nuclear excited power generation system

    SciTech Connect

    Parker, R.Z.; Cox, J.D.

    1989-03-28

    A power generation system is described, comprising: a gaseous core nuclear reactor; means for passing helium through the reactor, the helium being excited and forming alpha particles by high frequency radiation from the core of the gaseous core nuclear reactor; a reaction chamber; means for coupling chlorine and hydrogen to the reaction chamber, the helium and alpha particles energizing the chlorine and hydrogen to form a high temperature, high pressure hydrogen chloride plasma; means for converting the plasma to electromechanical energy; means for coupling the helium back to the gaseous core nuclear reactor; and means for disassociating the hydrogen chloride to form molecular hydrogen and chlorine, to be coupled back to the reaction chamber in a closed loop. The patent also describes a power generation system comprising: a gaseous core nuclear reactor; means for passing hydrogen through the reactor, the hydrogen being excited by high frequency radiation from the core; means for coupling chlorine to a reaction chamber, the hydrogen energizing the chlorine in the chamber to form a high temperature, high pressure hydrogen chloride plasma; means for converting the plasma to electromechanical energy; means for disassociating the hydrogen chloride to form molecular hydrogen and chlorine, and means for coupling the hydrogen back to the gaseous core nuclear reactor in a closed loop.

  11. Computer controlled solar thermal electrical generating facility in operation

    SciTech Connect

    Not Available

    1984-11-01

    This article describes the world's largest privately financed solar thermal electrical generating facility, Solarplant I. It is the first solar-powered plant built in a cost range that is competitive with nuclear-powered and fossil-fuel-powered plants. It is a 4.92-megawatt electric power plant that utilizes 700 LEC 460 parabolic dish solar concentrators. Calculations project that the plant will generate an average of at least 12,368,000 kWh of electricity per year. Virtually all aspects of this solar plant operation are computer controlled with both a master computer for overall plant monitoring and control and microprocessors on each individual concentrator to avoid downtime and software complexity. The microcomputer-based controllers determine the system start-up and shutdown procedures including controlling motors, valves, and other support devices. The controllers also track the sun and automatically adjust for any errors in positioning or placement to ensure optimum performance.

  12. Heliostat field layout for solar thermal power plants

    Microsoft Academic Search

    Hartung; Kindermann; W. Mayer

    1980-01-01

    The calculation of the optimum distribution of heliostats, serving a solar tower collector for solar thermal power generation, is considered. A theoretical basis for the problem is posed, encompassing physical characteristics of the heliostats, their number, and intensity of the reflected radiation from each unit in function of their layout. Theoretical results lead to numerical procedures (program package FAUST). Various

  13. Stability of open-cycle MHD generation system connected to power transmission line

    Microsoft Academic Search

    Nobuhiko Hayanose; Yoshitaka Inui; Motoo Ishikawa; Juro Umoto

    1998-01-01

    The stability of the binary combined system of an MHD generator and a synchronous generator, including inverter and power transmission system, is studied numerically. The binary combined power generation system is a pilot plant scale with thermal input of about 110MW and consists of a MHD generator as a topping cycle and a steam turbine generator as a bottoming cycle.

  14. Power generation from waste incineration

    SciTech Connect

    Kolb, J.O.; Wilkes, K.E.

    1988-06-01

    Incineration of municipal solid wastes (MSW) with heat recovery for power generation is being used increasingly in the US to reduce the volume of wastes to be landfilled. High-temperature incineration is also beginning to be used to decontaminate sites where hazardous chemicals were disposed of in the past with large amounts of heat usually wasted in such incinerators. This report presents a characterization of MSW incineration technologies, an energy market evaluation in the DADS area, an evaluation of energy recovery from waste tires, a conceptual design of an integrated incineration power plant, and an economic analysis of hazardous waste processing costs and potential savings with an integrated facility. Analyses of the amount and types of hazardous wastes, appropriate incineration technologies, a process design to size flue gas heat recovery equipment, and cost estimates for hazardous waste incinerator systems and heat recovery equipment were performed by Science Applications International Corporation (SAIC) in a companion study and used in this report. The primary conclusion of this study is that processing cost savings with an integrated waste incinerator power plant range from 6 to 20% of costs compared to separate hazardous waste incineration. However, this result depends on the amount and moisture content of the waste material and the electricity value sold to the local utility. Other results and conclusions include the types of hazardous waste incineration technologies recommended, the market for energy products, and institutional restraints and requirements. 32 refs., 17 figs., 20 tabs.

  15. Thermal characteristics of second harmonic generation by phase matched calorimetry.

    PubMed

    Lim, Hwan Hong; Kurimura, Sunao; Noguchi, Keisuke; Shoji, Ichiro

    2014-07-28

    We analyze a solution of the heat equation for second harmonic generation (SHG) with a focused Gaussian beam and simulate the temperature rise in SHG materials as a function of the second harmonic power and the focusing conditions. We also propose a quantitative value of the heat removal performance of SHG devices, referred to as the effective heat capacity C? in phase matched calorimetry. We demonstrate the inverse relation between C? and the focusing parameter ?, and propose the universal quantity of the product of C? and ? for characterizing the thermal property of SHG devices. Finally, we discuss the strategy to manage thermal dephasing in SHG using the results from simulations. PMID:25089446

  16. Solar Thermal Power Systems parabolic dish project

    NASA Technical Reports Server (NTRS)

    Truscello, V. C.

    1981-01-01

    The status of the Solar Thermal Power Systems Project for FY 1980 is summarized. Included is: a discussion of the project's goals, program structure, and progress in parabolic dish technology. Analyses and test results of concentrators, receivers, and power converters are discussed. Progress toward the objectives of technology feasibility, technology readiness, system feasibility, and system readiness are covered.

  17. Pv-Thermal Solar Power Assembly

    DOEpatents

    Ansley, Jeffrey H. (El Cerrito, CA); Botkin, Jonathan D. (El Cerrito, CA); Dinwoodie, Thomas L. (Piedmont, CA)

    2001-10-02

    A flexible solar power assembly includes a flexible photovoltaic device attached to a flexible thermal solar collector. The solar power assembly can be rolled up for transport and then unrolled for installation on a surface, such as the roof or side wall of a building or other structure, by use of adhesive and/or other types of fasteners.

  18. Identifying and bounding uncertainties in nuclear reactor thermal power calculations

    SciTech Connect

    Phillips, J.; Hauser, E.; Estrada, H. [Cameron, 1000 McClaren Woods Drive, Coraopolis, PA 15108 (United States)

    2012-07-01

    Determination of the thermal power generated in the reactor core of a nuclear power plant is a critical element in the safe and economic operation of the plant. Direct measurement of the reactor core thermal power is made using neutron flux instrumentation; however, this instrumentation requires frequent calibration due to changes in the measured flux caused by fuel burn-up, flux pattern changes, and instrumentation drift. To calibrate the nuclear instruments, steam plant calorimetry, a process of performing a heat balance around the nuclear steam supply system, is used. There are four basic elements involved in the calculation of thermal power based on steam plant calorimetry: The mass flow of the feedwater from the power conversion system, the specific enthalpy of that feedwater, the specific enthalpy of the steam delivered to the power conversion system, and other cycle gains and losses. Of these elements, the accuracy of the feedwater mass flow and the feedwater enthalpy, as determined from its temperature and pressure, are typically the largest contributors to the calorimetric calculation uncertainty. Historically, plants have been required to include a margin of 2% in the calculation of the reactor thermal power for the licensed maximum plant output to account for instrumentation uncertainty. The margin is intended to ensure a cushion between operating power and the power for which safety analyses are performed. Use of approved chordal ultrasonic transit-time technology to make the feedwater flow and temperature measurements (in place of traditional differential-pressure- based instruments and resistance temperature detectors [RTDs]) allows for nuclear plant thermal power calculations accurate to 0.3%-0.4% of plant rated power. This improvement in measurement accuracy has allowed many plant operators in the U.S. and around the world to increase plant power output through Measurement Uncertainty Recapture (MUR) up-rates of up to 1.7% of rated power, while also decreasing the probability of significant over-power events. This paper will examine the basic elements involved in calculation of thermal power using ultrasonic transit-time technology and will discuss the criteria for bounding uncertainties associated with each element in order to achieve reactor thermal power calculations to within 0.3% to 0.4%. (authors)

  19. Continuous power generation in space

    SciTech Connect

    Meckler, M.

    1999-07-01

    The major advantage of this new holographic technology is that spectrum splitting utilizes a more efficient side focus which eliminates shadow effects and prevents overheating by diffracting unwanted infrared radiation away from solar passive photovoltaic (PV) cells and transferring it directly to the boiler of a companion electrically-integrated solar dynamic Stirling or Brayton Cycle heat engine, thereby obtaining greater utilization of the available solar spectrum for power production in space, as will be seen. The proposed holographic elements are themselves lightweight, modular, durable, flat, economical and are highly suitable for deployment in a space environment. Fresnel reflective losses are lowered by using 20x or greater modular transmission holoconcentrator elements which focus light onto a line, thereby requiring long and narrow target solar cells. Shading and cell contact resistance are both reduced as a result of shorter, thinner contacts. Applying modular hexagonal elements will be shown to facilitate ease of construction for space assembly to form large flat sections, as power generating and receiving platforms that permit laser beaming to other satellites in GEO or LEO, as shown.

  20. ENHANCED THERMAL VACUUM TEST CAPABILITY FOR RADIOISOTOPE POWER SYSTEMS AT THE IDAHO NATIONAL LABORATORY BETTER SIMULATES ENVIRONMENTAL CONDITIONS OF SPACE

    Microsoft Academic Search

    J. C. Giglio; A. A. Jackson

    2012-01-01

    The Idaho National Laboratory (INL) is preparing to fuel and test the Advanced Stirling Radioisotope Generator (ASRG), the next generation space power generator. The INL identified the thermal vacuum test chamber used to test past generators as inadequate. A second vacuum chamber was upgraded with a thermal shroud to process the unique needs and to test the full power capability

  1. Environment Friendly Coal Based Power Generation in Pakistan

    NASA Astrophysics Data System (ADS)

    Qureshi, S. A.; Javed, M. Adnan

    2010-06-01

    The main emphasis of this paper is on the engineering economics and design developments in the field of thermal power generation in Pakistan. Pakistan is rich with coal fields but is making no use of this available natural resource to fulfil its energy demands. The shortage of power is getting worst day by day and to align with the power requirements, Pakistan needs to add 2000 MW each year to national grid. With the increasing prices of natural gas and oil, Pakistan should consider coal, the abundantly available natural resource, as an alternate fuel for its new power plants to overcome the power crises.

  2. A dish-Stirling solar-thermal power system

    NASA Technical Reports Server (NTRS)

    Pons, R. L.; Clark, T. B.

    1980-01-01

    This paper presents results of a preliminary design/economic study of a first-generation point focusing distributed receiver solar-thermal electric system optimized for application to industrial and small community power plants at power levels up to 10 MWe. Power conversion is provided by small Stirling cycle engines mounted at the focus of paraboloidal solar concentrators. The output of multiple power modules (concentrator, receiver, engine, and electric generator) is collected by means of a conventional electrical system and interfaced with a utility grid. Based on the United Stirling P-75 engine, a 1 MWe system employing mass-produced components (100,000 modules/year) could produce electricity at costs competitive with those projected for electricity generated by more conventional means, e.g. with fossil fuels.

  3. Small solar thermal electric power plants with early commercial potential

    NASA Technical Reports Server (NTRS)

    Jones, H. E.; Bisantz, D. J.; Clayton, R. N.; Heiges, H. H.; Ku, A. C.

    1979-01-01

    Cost-effective small solar thermal electric power plants (1- to 10-MW nominal size) offer an attractive way of helping the world meet its future energy needs. The paper describes the characteristics of a conceptual near-term plant (about 1 MW) and a potential 1990 commercial version. The basic system concept is one in which steam is generated using two-axis tracking, parabolic dish, and point-focusing collectors. The steam is transported through low-loss piping to a central steam turbine generator unit where it is converted to electricity. The plants have no energy storage and their output power level varies with the solar insolation level. This system concept, which is firmly based on state-of-the-art technology, is projected to offer one of the fastest paths for U.S. commercialization of solar thermal electric power plants through moderate technology advances and mass production.

  4. Alternative biomass sources for thermal energy generation

    NASA Astrophysics Data System (ADS)

    Steensen, Torge; Müller, Sönke; Dresen, Boris; Büscher, Olaf

    2015-04-01

    Traditionally, renewable biomass energy sources comprise forests, agriculture and other large vegetation units. With the increasing demand on those landscape elements, including conflicts of interest to nature conservation and food production, the research focus should also incorporate smaller vegetation entities. In this study, we highlight the availability of small-scale features like roadside vegetation or hedges, which are rarely featured in maps. Roadside vegetation, however, is well known and regularly trimmed to allow the passing of traffic but the cut material is rarely harvested. Here, we combine a remote-sensing-based approach to quantify the seasonal biomass harvests with a GIS-based method to outline optimal transportation routes to, and the location of, storage units and power plants. Our main data source will be ESA's upcoming Sentinel-2 optical satellite. Spatial resolution of 10 meters in the visible and near infrared requires the use of spectral unmixing to derive end member spectra of the targeted biomass objects. Additional stereo-matching and LIDAR measurements allow the accompanying height estimate to derive the biomass volume and its changes over time. GIS data bases from the target areas allow the discrimination between traditional, large features (e.g. forests and agriculture) as well as previously unaccounted for, smaller vegetation units. With the mapped biomass occurrence and additional, GIS-based infrastructure information, we can outline transport routes that take into account local restrictions like nature reserve areas, height or weight limitations as well as transport costs in relation to potential gains. This information can then be processed to outline optimal places for power plants. To simulate the upcoming Sentinel-2 data sets, we use airborne data from the AISA Eagle, spatially and spectrally down-sampled to match Sentinel 2's resolution. Our test scenario is an area in western Germany, the Kirchheller Heide, close to the city of Bottrop-Kirchhellen in the state of North Rhine-Westphalia. This region consists of nature reserves, forests, farmland and a few villages. To present a qualitative comparison between simulated and true biomass volume, we conducted field work by mapping the spatial extent of the desired biomass occurrences in the area. First results indicate a qualitative match of about 75%. Our research highlights the small-scale biomass features that have not been incorporated in previous biomass estimates. With the regular trimming and the accompanied raw material that becomes available, a new sector of thermal energy generation can be outlined. An automated quantification using satellite and GIS data will allow a regular monitoring of the vegetation growth and an assessment of the transport routes and costs as well as the location of the prospective power plants. In the endeavour of creating a sustainable energy supply, these biomass units should not be neglected, especially since the usage of the traditional units is limited due to competing interests in food production and nature conservation.

  5. Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

    NASA Technical Reports Server (NTRS)

    Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

    2014-01-01

    This paper presents recent thermal model results of the Advanced Stirling Radioisotope Generator (ASRG). The three-dimensional (3D) ASRG thermal power model was built using the Thermal Desktop(trademark) thermal analyzer. The model was correlated with ASRG engineering unit test data and ASRG flight unit predictions from Lockheed Martin's (LM's) I-deas(trademark) TMG thermal model. The auxiliary cooling system (ACS) of the ASRG is also included in the ASRG thermal model. The ACS is designed to remove waste heat from the ASRG so that it can be used to heat spacecraft components. The performance of the ACS is reported under nominal conditions and during a Venus flyby scenario. The results for the nominal case are validated with data from Lockheed Martin. Transient thermal analysis results of ASRG for a Venus flyby with a representative trajectory are also presented. In addition, model results of an ASRG mounted on a Cassini-like spacecraft with a sunshade are presented to show a way to mitigate the high temperatures of a Venus flyby. It was predicted that the sunshade can lower the temperature of the ASRG alternator by 20 C for the representative Venus flyby trajectory. The 3D model also was modified to predict generator performance after a single Advanced Stirling Convertor failure. The geometry of the Microtherm HT insulation block on the outboard side was modified to match deformation and shrinkage observed during testing of a prototypic ASRG test fixture by LM. Test conditions and test data were used to correlate the model by adjusting the thermal conductivity of the deformed insulation to match the post-heat-dump steady state temperatures. Results for these conditions showed that the performance of the still-functioning inboard ACS was unaffected.

  6. Thermal adaptation generates a diversity of thermal limits in a rainforest ant community.

    PubMed

    Kaspari, Michael; Clay, Natalie A; Lucas, Jane; Yanoviak, Stephen P; Kay, Adam

    2015-03-01

    The Thermal Adaptation Hypothesis posits that the warmer, aseasonal tropics generates populations with higher and narrower thermal limits. It has largely been tested among populations across latitudes. However, considerable thermal heterogeneity exists within ecosystems: across 31 trees in a Panama rainforest, surfaces exposed to sun were 8 °C warmer and varied more in temperature than surfaces in the litter below. Tiny ectotherms are confined to surfaces and are variously submerged in these superheated boundary layer environments. We quantified the surface CTmin and CTmax s (surface temperatures at which individuals grew torpid and lost motor control, respectively) of 88 ant species from this forest; they ranged in average mass from 0.01 to 57 mg. Larger ants had broader thermal tolerances. Then, for 26 of these species we again tested body CTmax s using a thermal dry bath to eliminate boundary layer effects: body size correlations observed previously disappeared. In both experiments, consistent with Thermal Adaptation, CTmax s of canopy ants averaged 3.5-5 °C higher than populations that nested in the shade of the understory. We impaled thermocouples in taxidermy mounts to further quantify the factors shaping operative temperatures for four ant species representing the top third (1-30 mg) of the size distribution. Extrapolations suggest the smallest 2/3rds of species reach thermal equilibrium in <10s. Moreover, the large ants that walk above the convective superheated surface air also showed more net heating by solar radiation, with operative temperatures up to 4 °C higher than surrounding air. The thermal environments of this Panama rainforest generate a range of CTmax subsuming 74% of those previously recorded for ant populations worldwide. The Thermal Adaptation Hypothesis can be a powerful tool in predicting diversity of thermal limits within communities. Boundary layer temperatures are likely key to predicting the future of Earth's tiny terrestrial ectotherm populations. PMID:25242246

  7. Impact of Power Generation Uncertainty on Power System Static Performance

    E-print Network

    Liberzon, Daniel

    , and difficult to forecast accurately, they present notable un- certainties to the operation of today's powerImpact of Power Generation Uncertainty on Power System Static Performance Yu Christine Chen, Xichen--The rapid growth in renewable energy resources such as wind and solar generation introduces significant

  8. Thermal storage requirements for parabolic dish solar power plants

    NASA Technical Reports Server (NTRS)

    Wen, L.; Steele, H.

    1980-01-01

    The cost effectiveness of a high temperature thermal storage system is investigated for a representative parabolic dish solar power plant. The plant supplies electrical power in accordance with a specific, seasonally varying demand profile. The solar power received by the plant is supplemented by power from fuel combustion. The cost of electricity generated by the solar power plant is calculated, using the cost of mass-producible subsystems (specifically, parabolic dishes, receivers, and power conversion units) now being designed for this type of solar plant. The trade-off between fuel and thermal storage is derived in terms of storage effectiveness, the cost of storage devices, and the cost of fuel. Thermal storage requirements, such as storage capacity, storage effectiveness, and storage cost are established based on the cost of fuel and the overall objective of minimizing the cost of the electricity produced by the system. As the cost of fuel increases at a rate faster than general inflation, thermal storage systems in the $40 to $70/kWthr range could become cost effective in the near future.

  9. Development and demonstration of compound parabolic concentrators for solar thermal power generation and heating and cooling applications. Progress report, July--December 1975

    Microsoft Academic Search

    J. W. Allen; N. M. Levitz; A. Rabl; K. A. Reed; W. W. Schertz; G. Thodos; R. Winston

    1977-01-01

    Work on the development of Compound Parabolic Concentrators (CPC) is described. A tenfold concentrator with a cavity receiver was constructed and tested. The optical efficiency was very good (65 percent), but the thermal performance was degraded by heat losses of the cavity receiver. A 20 ft² (1.86 m²) concentrating collector (5.3x) has been tested for thermal and optical performance, and

  10. Pulse power applications of flux compression generators

    SciTech Connect

    Fowler, C.M.; Caird, R.S.; Erickson, D.J.; Freeman, B.L.

    1981-01-01

    Characteristics are presented for two different types of explosive driven flux compression generators and a megavolt pulse transformer. Status reports are given for rail gun and plasma focus programs for which the generators serve as power sources.

  11. CMOS compatible Multiple Power-Output MEMS Radioisotope ?-Power Generator

    Microsoft Academic Search

    Rajesh Duggirala; A. Lai; Ronald G. Polcawich; Madan Dubey

    2006-01-01

    The authors demonstrate a novel 6.6% high-efficiency CMOS compatible piezoelectric aluminum nitride (AlN) thin-film based integrated ?-radioisotope-powered electro-mechanical power generator (IREMPG). the authors integrate silicon betavoltaics with radioisotope actuated piezoelectric unimorph converters to efficiently utilize both kinetic energy and charge of the emitted beta particles for electrical power generation. IREMPG has three output ports generating (1) a 2.8MHz pulse remotely

  12. PV/thermal solar power assembly

    DOEpatents

    Ansley, Jeffrey H.; Botkin, Jonathan D.; Dinwoodie, Thomas L.

    2004-01-13

    A flexible solar power assembly (2) includes a flexible photovoltaic device (16) attached to a flexible thermal solar collector (4). The solar power assembly can be rolled up for transport and then unrolled for installation on a surface, such as the roof (20, 25) or side wall of a building or other structure, by use of adhesive and/or other types of fasteners (23).

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

    NASA Technical Reports Server (NTRS)

    1979-01-01

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

  14. Integrated engine generator for aircraft secondary power

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.

    1972-01-01

    An integrated engine-generator for aircraft secondary power generation is described. The concept consists of an electric generator located inside a turbojet or turbofan engine and both concentric with and driven by one of the main engine shafts. The electric power conversion equipment and generator controls are located in the aircraft. When properly rated, the generator serves as an engine starter as well as a source of electric power. This configuration reduces or eliminates the need for an external gear box on the engine and permits reduction in the nacelle diameter.

  15. COST-EFFECTIVE AND RELIABLE DESIGN OF A SOLAR THERMAL POWER PLANT

    Microsoft Academic Search

    A. A. Aliabadi; S. Wallace

    A design study was conducted to evaluate the cost-effectiveness of solar thermal power generation in a 50 kWe power plant that could be used in a remote location. The system combines a solar collector-thermal storage system utilizing a heat transfer Huid and a simple Rankine cycle power generator utilizing R123 refrigerant. Evacuated tube solar collectors heat mineral oil and supply

  16. Radioisotope thermophotovoltaic generator for space power applications

    SciTech Connect

    Loughin, S. [Lockheed Martin Astro Space, Philadelphia, PA (United States); Uppal, P. [Lockheed Martin Labs., Baltimore, MD (United States)

    1995-12-31

    This paper presents a conceptual approach for a radioisotope thermophotovoltaic (RTPV) generator based on a photovoltaic converter tuned to the General Purpose Heat Source -- the standard thermal source for space power applications such as Voyager, Galileo, Ulysses, and Cassini. Recent work suggests that the RTPV approach offers greater efficiency than the present thermoelectric technology. In this paper the authors discuss an approach based on photovoltaic devices made from a quaternary III-IV alloy, Ga{sub x}In{sub 1{minus}x}As{sub y}Sb{sub 1{minus}y}, with a tandem dielectric/plasma filter. The Ga{sub x}In{sub 1{minus}x}As{sub y}Sb{sub 1{minus}y} devices have been fabricated by molecular beam epitaxy, and are lattice-matched to GaSb substrates. The quality of the quaternary alloys, evaluated by x-ray diffraction and photoluminescence, is quite good. The authors obtain quantum efficiencies up to 78% with these quaternary alloys, indicative of excellent minority carrier device potential of these layers. For plasma filters the authors have used heavily-doped, thin layers of Si and obtain a sharp plasma resonance. Device performance data for these quaternary photovoltaic cells, including current, voltage, fill-factor; as well as filter performance data, including transmission, reflection and absorption are presented. The impact of these factors on system performance for a small radioisotope generator system is also discussed.

  17. Optimization of power and efficiency of thermoelectric devices with asymmetric thermal contacts

    E-print Network

    2012) We report the theoretical efficiency of thermoelectric power generation with asymmetric thermalOptimization of power and efficiency of thermoelectric devices with asymmetric thermal contacts of temperature-dependent interfacial resistance of thermoelectric modules Rev. Sci. Instrum. 82, 116109 (2011

  18. Solar thermal power systems. Summary report

    SciTech Connect

    Not Available

    1980-06-01

    The work accomplished by the Aerospace Corporation from April 1973 through November 1979 in the mission analysis of solar thermal power systems is summarized. Sponsorship of this effort was initiated by the National Science Foundation, continued by the Energy Research and Development Administration, and most recently directed by the United States Department of Energy, Division of Solar Thermal Systems. Major findings and conclusions are sumarized for large power systems, small power systems, solar total energy systems, and solar irrigation systems, as well as special studies in the areas of energy storage, industrial process heat, and solar fuels and chemicals. The various data bases and computer programs utilized in these studies are described, and tables are provided listing financial and solar cost assumptions for each study. An extensive bibliography is included to facilitate review of specific study results and methodology.

  19. Coal gasification for advanced power generation

    Microsoft Academic Search

    Andrew J. Minchener

    2005-01-01

    This paper provides a review of the development and deployment of coal based gasification technologies for power generation. The global status of gasification is described covering the various process and technology options. The use of gasification for power generation is then highlighted including the advantages and disadvantages of this means for coal utilisation. The R, D & D needs and

  20. Generation control for deregulated electric power systems

    Microsoft Academic Search

    Robert P. Schulte

    2000-01-01

    Open access transmission brings the need and the opportunity to make generation delivery changes. The predominant delivery control now used presents difficulties. It has a territorial control area structure with continuous power flow telemetering at area boundaries. Community control is proposed. It relies on the inherent primary control of generator governors and does away with secondary control of boundary power

  1. Power electronics as efficient interface in dispersed power generation systems

    Microsoft Academic Search

    Frede Blaabjerg; Zhe Chen; S. B. Kjaer

    2004-01-01

    The global electrical energy consumption is rising and there is a steady increase of the demand on the power capacity, efficient production, distribution and utilization of energy. The traditional power systems are changing globally, a large number of dispersed generation (DG) units, including both renewable and nonrenewable energy sources such as wind turbines, photovoltaic (PV) generators, fuel cells, small hydro,

  2. Waste Heat Recovery Power Generation with WOWGen

    E-print Network

    Romero, M.

    or combinations of sources can be used to generate power. WOWGen? can also be used with stand alone power plants burning fossil fuels or using renewable energy sources such as solar and biomass. Technology W O W has two patents on WOWGen? power generation....223.1338 Email: Hmromero@WOWenergies.comH URL: Hwww.WOWenergies.com Industry Energy Efficiency Products WOWGen? - Waste Heat Recovery WOWClean? - Pollution control Intellectual Property Two Patents issued Trade secrets ESL-IE-09...

  3. Thermoelectric power generation for battery charging

    Microsoft Academic Search

    Mahmudur Rahman; Roger Shuttleworth

    1995-01-01

    Thermoelectric generators use the Seebeck effect to produce electrical power from a temperature difference caused by heat energy flow. In this paper the principle of using thermoelectrically converted heat energy for powering portable electronic equipment or charging its battery has been investigated for a lap-top computer. The thermoelectric battery charger developed, consists of a thermoelectric converter system, powered from butane

  4. Review of Microscale Magnetic Power Generation

    Microsoft Academic Search

    David P. Arnold

    2007-01-01

    This paper discusses the history, current state of the art, and ongoing challenges for compact (less than a few cubic centimeters) magnetic power generation systems in the microwatts to tens of watts power range. These systems are of great interest for powering sensor networks, robotics, wireless communication systems, and other portable electronics. The paper considers the following topics. 1) The

  5. MEMS Radioisotope-Powered Piezoelectric µ - Power Generator (RPG)

    Microsoft Academic Search

    R. Duggirala; R. Polcawich; E. Zakar; M. Dubey; H. Li; A. Lal

    2006-01-01

    We present a microfabricated die-scale Radioisotope-powered Piezoelectric µ -power Generator (RPG) with nuclear to electrical conversion efficiency as high as 3.7%. The generator employs direct charging to convert radiated ?-particle kinetic energy into stored electromechanical energy in a piezoelectric unimorph, and piezoelectricity to convert the stored mechanical energy into extractable electrical energy. The generator goes through a charge-discharge-vibrate cycle, integrating

  6. Next generation materials for thermal interface and high density energy storage applications via liquid phase sintering

    Microsoft Academic Search

    J. Liu; P. Rottman; S. Dutta; P. Kumar; R. Raj; M. Renavikar; I. Dutta

    2009-01-01

    With the continuing increase in power dissipation requirements of electronic devices, there is a need to develop new thermal interface materials (TIM) with much higher thermal conductivity (K) than that available from conventional TIMs. Recently, liquid phase sintering (LPS) has been proposed as a new paradigm for designing next generation composite-solder TIMs with a radically different microstructure from those of

  7. Thermal properties of high-power transistors

    Microsoft Academic Search

    R. H. Winkler

    1967-01-01

    The temperature of a transistor can be determined from the emitter-base voltage versus collector-current characteristic. This characteristic was used for studying the stability of parallel pairs of high-frequency high-power transistors. The thermal effect may cause the incremental emitter-base resistance to assume a negative value. This, in turn, will cause the current flow in a pair of transistors to be asymmetrical.

  8. Thermal analysis of high-power modules

    Microsoft Academic Search

    C. Van Godbold; V. Anand Sankaran; Jerry L. Hudgins

    1997-01-01

    A highly descriptive method for displaying heat flow in power modules is presented. Heat flow is studied for three different transistor-stack types: direct bond copper (DEC), thick-film printed substrate, and insulated metal substrate (IMS). DEC and thick film are thermally superior to IMS, but IMS shows potential. In addition, the effect of case-to-sink interface conductivity on heat flow is studied

  9. Thermally regenerative hydrogen\\/oxygen fuel cell power cycles

    Microsoft Academic Search

    J. H. Morehouse

    1986-01-01

    Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle,

  10. Where solar thermal meets photovoltaic for high-efficiency power conversion

    E-print Network

    Bierman, David M. (David Matthew)

    2014-01-01

    To develop disruptive techniques which generate power from the Sun, one must understand the aspects of existing technologies that limit performance. Solar thermal and solar photovoltaic schemes dominate today's solar market ...

  11. Thermal Analysis of the Z-Pinch Power Plant Concept

    SciTech Connect

    Modesto, M.A.; Lindgren, E.R.; Morrow, C.W. [Sandia National Laboratories (United States)

    2005-04-15

    In this work, a preliminary thermal model for the Z-Pinch Power Plant is presented. This power plant utilizes fusion energy to generate electric energy in the GW range. The Z-Pinch Technology consists of compressing high-density plasma to produce X-rays to indirectly heat to ignition a deuterium/tritium fusion capsule. This ignition releases a minimum of 3 GJ every 10 seconds. The thermal energy generated is absorbed by the primary cycle fluid, and it is later used to power a Brayton or Rankine cycle. An advanced heat exchanger is used as the interface between the two cycles. This heat exchanger plays an important role in power plant performance. Three fluids (Flibe, Pb-17Li, and Li) were used for the plant performance analysis. The thermodynamic properties of the selected fluids determine the maximum operating temperature of the power cycles. Model results show that high temperatures (over 1000 deg. C) are developed in the primary cycle as needed to efficiently run the secondary cycle. The results of the performance parametric study demonstrated that the Brayton cycle exhibits better performance characteristics than the Rankine cycle for this type of application.

  12. Therminator: Thermal heavy-Ion generator

    E-print Network

    Adam Kisiel; Tomasz Taluc; Wojciech Broniowski; Wojciech Florkowski

    2005-09-27

    THERMINATOR is a Monte Carlo event generator designed for studying of particle production in relativistic heavy-ion collisions performed at such experimental facilities as the SPS, RHIC, or LHC. The program implements thermal models of particle production with single freeze-out. It performs the following tasks: 1) generation of stable particles and unstable resonances at the chosen freeze-out hypersurface with the local phase-space density of particles given by the statistical distribution factors, 2) subsequent space-time evolution and decays of hadronic resonances in cascades, 3) calculation of the transverse-momentum spectra and numerous other observables related to the space-time evolution. The geometry of the freeze-out hypersurface and the collective velocity of expansion may be chosen from two successful models, the Cracow single-freeze-out model and the Blast-Wave model. All particles from the Particle Data Tables are used. Experimental cuts may be introduced in a very straightforward manner. The code is written in the object-oriented c++ language and complies to the standards of the ROOT environment.

  13. COMPACT MARX GENERATORS FOR THE GENERATION OF HIGH POWER MICROWAVES

    Microsoft Academic Search

    J. R. Mayes; W. J. Carey; W. C. Nunnally; L. Altgilbers; M. Kristiansen

    Traditional Marx generators have been primarily reserved for energy storage and pulse-charging sources. However, recent work 4 has demonstrated the Marx generator's effectiveness in delivering ultra-short impulses at very intense power levels. This paper discusses two very compact Marx generators capable of delivering voltage pulses of several hundred kV, durations of several nano-seconds to 10's of nanoseconds, and risetimes as

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

    Microsoft Academic Search

    John Chung-Ling Chien; Noam Lior

    2011-01-01

    Study of low-carbon and pollution renewable alternatives for China revealed that concentrating solar thermal (CST) electric power generation was underemphasized in China's renewable energy plan. The analysis shows the competitive viability of CST: (1) China has the key prerequisites to make CST power generation economical including high-quality insolation and appropriate land, (2) CST's proven history, scale, and dispatchability makes it

  15. A recursive economic dispatch algorithm for assessing the cost of thermal generator schedules

    SciTech Connect

    Wong, K.P.; Doan, K. (Dept. of Electrical and Electronic Engineering, Univ. of Western Australia, Nedlands, Western Australia 6009 (AU))

    1992-05-01

    This paper develops an efficient, recursive algorithm for determining the economic power dispatch of thermal generators within the unit commitment environment. A method for incorporating the operation limits of all on-line generators and limits due to ramping generators is developed in the paper. The developed algorithm is amenable for computer implementation using the artificial intelligence programming language, Prolog. The performance of the developed algorithm is demonstrated through its application to evaluate the costs of dispatching 13 thermal generators within a generator schedule in a 24-hour schedule horizon.

  16. Skutterudite Thermoelectric Generator for Electrical Power Generation from Automotive Waste Heat

    NASA Astrophysics Data System (ADS)

    Meisner, Gregory

    2012-02-01

    Filled skutterudites are state-of-the- art thermoelectric (TE) materials for electrical power generation from waste heat. They have suitable intrinsic transport properties as measured by the thermoelectric figure of merit ZT = S^2?T/? (S = Seebeck coefficient, ? = electrical conductivity, T = temperature, and ? = thermal conductivity) and good mechanical strength for operation at vehicle exhaust gas temperatures of >550 C. We have demonstrated TE electrical power generation on a production test vehicle equipped with a fully functional prototype TE generator (TEG). It was assembled with TE modules fabricated from filled skutterudites synthesized at GM. Our results and analysis show that improvement in total power generated can be achieved by enhanced thermal and electrical interfaces and contacts. A substantial T decrease along the exhaust gas flow results in a large variation of voltage, current, and power output for each TE module depending on its position in the module array. Total TEG output power depends directly on the position-dependent T profile via the temperature dependence of both ZT and Carnot efficiency. Total TEG power output also depends on how the modules are connected in parallel or series combinations because mismatch in output voltage and/or internal resistance among the modules degrades the performance of the entire array. Uniform T profiles and consistent TE module internal resistances improve overall TEG performance.

  17. Electric energy production by particle thermionic-thermoelectric power generators

    NASA Technical Reports Server (NTRS)

    Oettinger, P. E.

    1980-01-01

    Thermionic-thermoelectric power generators, composed of a thin layer of porous, low work function material separating a heated emitter electrode and a cooler collector electrode, have extremely large Seebeck coefficients of over 2 mV/K and can provide significant output power. Preliminary experiments with 20-micron thick (Ba Sr Ca)O coatings, limited by evaporative loss to temperatures below 1400 K, have yielded short circuit current densities of 500 mA/sq cm and power densities of 60 mW/ sq cm. Substantially more output is expected with cesium-coated refractory oxide particle coatings operating at higher temperatures. Practical generators will have thermal-to-electrical efficiencies of 10 to 20%. Further increases can be gained by cascading these high-temperature devices with lower temperature conventional thermoelectric generators.

  18. Performance analysis of commercial scale Ar–Cs disk MHD generator connected to electric power system with synchronous generator

    Microsoft Academic Search

    L Kang; Y Inui; T Matsuo; M Ishikawa; J Umoto

    2000-01-01

    Performance analyses of a commercial scale closed-cycle MHD disk generator are performed. A large scale MHD generator, superconducting magnet, inversion system and synchronous generator are designed. The MHD generator is operated with Ar–Cs plasma and connected to the ac power infinite bus through line-commutated inverters, while the synchronous generator is operated in parallel. The thermal input is 1000 MW, and

  19. Solar thermoelectrics for small scale power generation

    E-print Network

    Amatya, Reja

    2012-01-01

    In the past two decades, there has been a surge in the research of new thermoelectric (TE) materials, driven party by the need for clean and sustainable power generation technology. Utilizing the Seebeck effect, the ...

  20. Analysis of power generation processes using petcoke 

    E-print Network

    Jayakumar, Ramkumar

    2009-05-15

    Petroleum coke or petcoke, a refinery byproduct, has generally been considered as an unusable byproduct because of its high sulfur content. However energy industries now view petcoke as a potential feedstock for power generation because it has...

  1. Waste Heat Recovery Power Generation with WOWGen 

    E-print Network

    Romero, M.

    2009-01-01

    WOW operates in the energy efficiency field- one of the fastest growing energy sectors in the world today. The two key products - WOWGen® and WOWClean® provide more energy at cheaper cost and lower emissions. •WOWGen® - Power Generation from...

  2. Hybrid solar-fossil fuel power generation

    E-print Network

    Sheu, Elysia J. (Elysia Ja-Zeng)

    2012-01-01

    In this thesis, a literature review of hybrid solar-fossil fuel power generation is first given with an emphasis on system integration and evaluation. Hybrid systems are defined as those which use solar energy and fuel ...

  3. Analysis of power generation processes using petcoke

    E-print Network

    Jayakumar, Ramkumar

    2009-05-15

    Petroleum coke or petcoke, a refinery byproduct, has generally been considered as an unusable byproduct because of its high sulfur content. However energy industries now view petcoke as a potential feedstock for power generation because it has...

  4. Power generation method including membrane separation

    DOEpatents

    Lokhandwala, Kaaeid A. (Union City, CA)

    2000-01-01

    A method for generating electric power, such as at, or close to, natural gas fields. The method includes conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas by means of a membrane separation step. This step creates a leaner, sweeter, drier gas, which is then used as combustion fuel to run a turbine, which is in turn used for power generation.

  5. Low thermal resistance power module assembly

    DOEpatents

    Hassani, Vahab (Denver, CO); Vlahinos, Andreas (Castle Rock, CO); Bharathan, Desikan (Arvada, CO)

    2007-03-13

    A power module assembly with low thermal resistance and enhanced heat dissipation to a cooling medium. The assembly includes a heat sink or spreader plate with passageways or openings for coolant that extend through the plate from a lower surface to an upper surface. A circuit substrate is provided and positioned on the spreader plate to cover the coolant passageways. The circuit substrate includes a bonding layer configured to extend about the periphery of each of the coolant passageways and is made up of a substantially nonporous material. The bonding layer may be solder material which bonds to the upper surface of the plate to provide a continuous seal around the upper edge of each opening in the plate. The assembly includes power modules mounted on the circuit substrate on a surface opposite the bonding layer. The power modules are positioned over or proximal to the coolant passageways.

  6. Coupled Electro-Thermal Simulations of Single Event Burnout in Power Diodes

    E-print Network

    Walker, D. Greg

    Coupled Electro-Thermal Simulations of Single Event Burnout in Power Diodes 1. Department;Motivation · Cosmic rays can cause Single event Burnout (SEB) in power electronic devices in space (e image of burnout in an IRF 150 power MOSFET #12;· Ion-generated charge is multiplied by avalanching

  7. Dislocation Generation by Thermal Stresses in Si: Modeling and Experiments

    SciTech Connect

    Sopori, B.; Sheldon, P.; Rupnowski, P.; Balzar, D.

    2005-11-01

    We developed a finite-element modeling program to predict the thermally generated dislocation distribution in a wafer. This model uses measured parameters that are determined from generating dislocations under a known optical flux.

  8. Power electronics and alternative energy generation

    Microsoft Academic Search

    James P Lyons; Vlatko Vlatkovic

    2004-01-01

    Growth in alterative energy generation technologies and markets will have a major impact on the development of power electronics in the future. The paper discusses some of these implications, and outlines the technological and performance challenges for power electronic systems in alternative energy applications.

  9. Solar operated closed system power generator

    Microsoft Academic Search

    deGeus

    1978-01-01

    A solar operated closed system power generator is provided in which a low boiling fluid is vaporized and superheated by solar energy concentrated within a parabolic reflector upon an elongated boiler which extends along the focus of the reflector. A turbine is connected to the boiler for obtaining power by the expansion of superheated vapor. The expanded vapors are condensed

  10. Residential Solar Combined Heat and Power Generation using Solar Thermoelectric Generation

    NASA Astrophysics Data System (ADS)

    Ohara, B.; Wagner, M.; Kunkle, C.; Watson, P.; Williams, R.; Donohoe, R.; Ugarte, K.; Wilmoth, R.; Chong, M. Zachary; Lee, H.

    2015-06-01

    Recent reports on improved efficiencies of solar thermoelectric generation (STEG) systems have generated interest in STEGs as a competitive power generation system. In this paper, the design of a combined cooling and power utilizing concentrated solar power is discussed. Solar radiation is concentrated into a receiver connected to thermoelectric modules, which are used as a topping cycle to generate power and high grade heat necessary to run an absorption chiller. Modeling of the overall system is discussed with experimental data to validate modeling results. A numerical modeling approach is presented which considers temperature variation of the source and sink temperatures and is used to maximize combined efficiency. A system is built with a demonstrated combined efficiency of 32% in actual working conditions with power generation of 3.1 W. Modeling results fell within 3% of the experimental results verifying the approach. An optimization study is performed on the mirror concentration ration and number of modules for thermal load matching and is shown to improve power generation to 26.8 W.

  11. Automatic steam generator control at low power

    Microsoft Academic Search

    1990-01-01

    This paper describes, in a pressurized water nuclear reactor steam supply system having a circulating steam generator including a feedwater pump, a main feedwater valve and a bypass feedwater valve having a lower flow capacity than that of the mainfeed water valve, a method for controlling the water level in the steam generator during operation in a low power regime

  12. Thermal expansion and conductivity of magnetite flakes taken from the Oconee-2 steam generator

    Microsoft Academic Search

    M. P. Manahan

    1990-01-01

    Flakes consisting primarily of iron oxides (magnetite) have been discovered in the spaces between tubes and support plates in steam generators, increasing flow resistance and causing abnormal increases in water levels. To aid in the determination of the effects of tube scale on steam generators, Duke Power Company and MPR Associates, Inc. arranged for the author to measure the thermal

  13. A Thermoelectric Generation System and Its Power Electronics Stage

    NASA Astrophysics Data System (ADS)

    Gao, Junling; Sun, Kai; Ni, Longxian; Chen, Min; Kang, Zhengdong; Zhang, Li; Xing, Yan; Zhang, Jianzhong

    2012-06-01

    The electricity produced by a thermoelectric generator (TEG) must satisfy the requirements of specific loads given the signal level, stability, and power performance. In the design of such systems, one major challenge involves the interactions between the thermoelectric power source and the power stage and signal-conditioning circuits of the load, including DC-DC conversion, the maximum power point tracking (MPPT) controller, and other power management controllers. In this paper, a survey of existing power electronics designs for TEG systems is presented first. Second, a flat, wall-like TEG system consisting of 32 modules is experimentally optimized, and the improved power parameters are tested. Power-conditioning circuitry based on an interleaved boost DC-DC converter is then developed for the TEG system in terms of the tested power specification. The power electronics design features a combined control scheme with an MPPT and a constant output voltage as well as the low-voltage and high-current output characteristics of the TEG system. The experimental results of the TEG system with the power electronics stage and with purely resistive loads are compared. The comparisons verify the feasibility and effectiveness of the proposed design. Finally, the thermal-electric coupling effects caused by current-related heat source terms, such as the Peltier effect etc., are reported and discussed, and the potential influence on the power electronics design due to such coupling is analyzed.

  14. Integrated propulsion and power modeling for bimodal nuclear thermal rockets

    NASA Astrophysics Data System (ADS)

    Clough, Joshua

    Bimodal nuclear thermal rocket (BNTR) engines have been shown to reduce the weight of space vehicles to the Moon, Mars, and beyond by utilizing a common reactor for propulsion and power generation. These savings lead to reduced launch vehicle costs and/or increased mission safety and capability. Experimental work of the Rover/NERVA program demonstrated the feasibility of NTR systems for trajectories to Mars. Numerous recent studies have demonstrated the economic and performance benefits of BNTR operation. Relatively little, however, is known about the reactor-level operation of a BNTR engine. The objective of this dissertation is to develop a numerical BNTR engine model in order to study the feasibility and component-level impact of utilizing a NERVA-derived reactor as a heat source for both propulsion and power. The primary contribution is to provide the first-of-its-kind model and analysis of a NERVA-derived BNTR engine. Numerical component models have been modified and created for the NERVA reactor fuel elements and tie tubes, including 1-D coolant thermodynamics and radial thermal conduction with heat generation. A BNTR engine system model has been created in order to design and analyze an engine employing an expander-cycle nuclear rocket and Brayton cycle power generator using the same reactor. Design point results show that a 316 MWt reactor produces a thrust and specific impulse of 66.6 kN and 917 s, respectively. The same reactor can be run at 73.8 kWt to produce the necessary 16.7 kW electric power with a Brayton cycle generator. This demonstrates the feasibility of BNTR operation with a NERVA-derived reactor but also indicates that the reactor control system must be able to operate with precision across a wide power range, and that the transient analysis of reactor decay heat merits future investigation. Results also identify a significant reactor pressure-drop limitation during propulsion and power-generation operation that is caused by poor tie tube thermal conductivity. This leads to the conclusion that, while BNTR operation is possible with a NERVA-derived reactor, doing so requires careful consideration of the Brayton cycle design point and fuel element survivability.

  15. ENHANCED THERMAL VACUUM TEST CAPABILITY FOR RADIOISOTOPE POWER SYSTEMS AT THE IDAHO NATIONAL LABORATORY BETTER SIMULATES ENVIRONMENTAL CONDITIONS OF SPACE

    SciTech Connect

    J. C. Giglio; A. A. Jackson

    2012-03-01

    The Idaho National Laboratory (INL) is preparing to fuel and test the Advanced Stirling Radioisotope Generator (ASRG), the next generation space power generator. The INL identified the thermal vacuum test chamber used to test past generators as inadequate. A second vacuum chamber was upgraded with a thermal shroud to process the unique needs and to test the full power capability of the new generator. The thermal vacuum test chamber is the first of its kind capable of testing a fueled power system to temperature that accurately simulate space. This paper outlines the new test and set up capabilities at the INL.

  16. Power costs of thirteen electric generation technologies

    SciTech Connect

    Lang, R.C.; Doyle, J.F.

    1983-01-01

    This paper reports on a study performed for the Bonneville Power Administration (BPA) to estimate as consistently as possible the cost of future generating technologies using renewable and conventional resources and highly fuel-efficient systems. The primary objective of the study was to evaluate future generating technologies by calculating the 30-yr. levelized busbar power costs of each technology on a consistent basis. Esimates for capital costs, operating costs, project schedules, fuel costs, annual energy generation and cost uncertainty were developed for the busbar power cost analysis. The study was designed to produce the most objective and consistent cost estimates possible for all of the generating technologies. The analysis of the uncertainty in capital cost and project schedule shows that there is a high level of uncertainty in the future costs for the developing technologies. Includes 5 tables.

  17. Compensation Method for Fluctuation Power of Wind Power Generation Using Biomass Gas Turbine Generator and Flywheel Energy Storage Equipment

    Microsoft Academic Search

    Masahiko Hara; Naoki Yamamura; Muneaki Ishida; Masaaki Wakita; Yasunari Kamada; Takao Maeda

    2008-01-01

    The power generation using natural energy contains electric power fluctuation. Therefore, in order to put such power generation system to practical use, compensation for system power fluctuation is needed. In this paper, we propose a power compensation method using biomass gas turbine generator and flywheel energy storage equipment. The gas turbine generator is used for compensation of low frequency power

  18. 43 CFR 431.6 - Power generation estimates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Power generation estimates. 431.6 Section...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.6 Power generation estimates....

  19. 43 CFR 431.4 - Power generation responsibilities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2011-10-01 true Power generation responsibilities. 431.4...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.4 Power generation responsibilities....

  20. 43 CFR 431.4 - Power generation responsibilities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Power generation responsibilities. 431.4...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.4 Power generation responsibilities....

  1. 43 CFR 431.4 - Power generation responsibilities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Power generation responsibilities. 431.4...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.4 Power generation responsibilities....

  2. ENERGY PAYBACK OPTIMIZATION OF THERMOELECTRIC POWER GENERATOR SYSTEMS

    E-print Network

    ENERGY PAYBACK OPTIMIZATION OF THERMOELECTRIC POWER GENERATOR SYSTEMS Kazuaki Yazawa Dept model for optimizing thermoelectric power generation system is developed and utilized for parametric a fractional area of ~1%. The role of the substrate heat spreading for thermoelectric power generation

  3. 43 CFR 431.4 - Power generation responsibilities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Power generation responsibilities. 431.4...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.4 Power generation responsibilities....

  4. 43 CFR 431.6 - Power generation estimates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Power generation estimates. 431.6 Section...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.6 Power generation estimates....

  5. 43 CFR 431.4 - Power generation responsibilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Power generation responsibilities. 431.4...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.4 Power generation responsibilities....

  6. 43 CFR 431.6 - Power generation estimates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Power generation estimates. 431.6 Section...THE INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE...PROJECT, ARIZONA/NEVADA § 431.6 Power generation estimates....

  7. New Generation Power System for Space Applications

    NASA Technical Reports Server (NTRS)

    Jones, Loren; Carr, Greg; Deligiannis, Frank; Lam, Barbara; Nelson, Ron; Pantaleon, Jose; Ruiz, Ian; Treicler, John; Wester, Gene; Sauers, Jim; Giampoli, Paul; Haskell, Russ; Mulvey, Jim; Repp, John

    2004-01-01

    The Deep Space Avionics (DSA) Project is developing a new generation of power system building blocks. Using application specific integrated circuits (ASICs) and power switching modules a scalable power system can be constructed for use on multiple deep space missions including future missions to Mars, comets, Jupiter and its moons. The key developments of the DSA power system effort are five power ASICs and a mod ule for power switching. These components enable a modular and scalab le design approach, which can result in a wide variety of power syste m architectures to meet diverse mission requirements and environments . Each component is radiation hardened to one megarad) total dose. The power switching module can be used for power distribution to regular spacecraft loads, to propulsion valves and actuation of pyrotechnic devices. The number of switching elements per load, pyrotechnic firin gs and valve drivers can be scaled depending on mission needs. Teleme try data is available from the switch module via an I2C data bus. The DSA power system components enable power management and distribution for a variety of power buses and power system architectures employing different types of energy storage and power sources. This paper will describe each power ASIC#s key performance characteristics as well a s recent prototype test results. The power switching module test results will be discussed and will demonstrate its versatility as a multip urpose switch. Finally, the combination of these components will illu strate some of the possible power system architectures achievable fro m small single string systems to large fully redundant systems.

  8. Thermally regenerative hydrogen\\/oxygen fuel cell power cycles

    Microsoft Academic Search

    Morehouse

    1988-01-01

    Two thermodynamic power cycles are analytically examined for future engineering feasibility. These power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The first cycle uses a thermal energy input at over 2000K to thermally dissociate the water. The second cycle dissociates the water using

  9. Solar Stirling power generation - Systems analysis and preliminary tests

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K.; Wu, Y.-C.; Moynihan, P. I.; Day, F. D., III

    1977-01-01

    The feasibility of an electric power generation system utilizing a sun-tracking parabolic concentrator and a Stirling engine/linear alternator is being evaluated. Performance predictions and cost analysis of a proposed large distributed system are discussed. Design details and preliminary test results are presented for a 9.5 ft diameter parabolic dish at the Jet Propulsion Laboratory (Caltech) Table Mountain Test Facility. Low temperature calorimetric measurements were conducted to evaluate the concentrator performance, and a helium flow system is being used to test the solar receiver at anticipated working fluid temperatures (up to 650 or 1200 C) to evaluate the receiver thermal performance. The receiver body is designed to adapt to a free-piston Stirling engine which powers a linear alternator assembly for direct electric power generation. During the next phase of the program, experiments with an engine and receiver integrated into the concentrator assembly are planned.

  10. Individual Module Maximum Power Point Tracking for Thermoelectric Generator Systems

    E-print Network

    Schaltz, Erik

    Individual Module Maximum Power Point Tracking for Thermoelectric Generator Systems Casper Vadstrup of Thermo Electric Generator (TEG) systems a power converter is often inserted between the TEG system

  11. Application of the subatmospheric engine to solar thermal power

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The development of a natural gas-fired Brayton engine is discussed. It is intended to be the prime mover for a 10-ton commercial heat pump. This engine has many attractive features that make it an ideal candidate for solar thermal-power generation applications. The unique feature of this engine is its subatmospheric mode of operation. It operates between atmospheric pressure and a partial vacuum. This means that heat is added to the cycle at atmospheric pressure; this permits the receiver to be unpressurized, greatly simplifying its design and cost.

  12. Flywheel-powered X-ray generator

    NASA Technical Reports Server (NTRS)

    Siedband, M. P.

    1984-01-01

    The use of a small flywheel appears to be a practical alternative to other power sources for mobile X-ray system applications. A 5 kg flywheel has been constructed which runs at 10 krpm and stores 30 KJ while requiring less than 500 W to bring the system up to speed. The wheel is coupled to an aircraft alternator and can yield pulsed power levels over 50 KWp. The aircraft alternator has the advantage of high frequency output which has also permitted the design of smaller high voltage transformers. A series of optical sensors detecting shaft position function as an electronic commutator so that the alternator may operate as a motor to bring the wheel up to operating speed. The system permits the generation of extremely powerful X-rays from a variety of low power sources such as household power outlets, automobile batteries or sources of poorly regulated electrical power such as those found in third world countries.

  13. Superconductive Random Number Generator Using Thermal Noises in SFQ Circuits

    Microsoft Academic Search

    Yuki Yamanashi; Nobuyuki Yoshikawa

    2009-01-01

    A novel high-speed physical random number generator using the superconductive single-flux-quantum (SFQ) circuits and thermal noises in the circuit has been proposed. The proposed physical random number generator is similar to an SFQ balanced comparator. Thermal noises in shunt resisters are used to obtain random outputs. Because of the high-sensitivity of SFQ circuits, the true random numbers can be generated

  14. Thermoelectric Fabrics: Toward Power Generating Clothing

    NASA Astrophysics Data System (ADS)

    Du, Yong; Cai, Kefeng; Chen, Song; Wang, Hongxia; Shen, Shirley Z.; Donelson, Richard; Lin, Tong

    2015-03-01

    Herein, we demonstrate that a flexible, air-permeable, thermoelectric (TE) power generator can be prepared by applying a TE polymer (e.g. poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)) coated commercial fabric and subsequently by linking the coated strips with a conductive connection (e.g. using fine metal wires). The poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) coated fabric shows very stable TE properties from 300 K to 390 K. The fabric device can generate a TE voltage output (V) of 4.3 mV at a temperature difference (?T) of 75.2 K. The potential for using fabric TE devices to harvest body temperature energy has been discussed. Fabric-based TE devices may be useful for the development of new power generating clothing and self-powered wearable electronics.

  15. Thermoelectric Fabrics: Toward Power Generating Clothing

    PubMed Central

    Du, Yong; Cai, Kefeng; Chen, Song; Wang, Hongxia; Shen, Shirley Z.; Donelson, Richard; Lin, Tong

    2015-01-01

    Herein, we demonstrate that a flexible, air-permeable, thermoelectric (TE) power generator can be prepared by applying a TE polymer (e.g. poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)) coated commercial fabric and subsequently by linking the coated strips with a conductive connection (e.g. using fine metal wires). The poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) coated fabric shows very stable TE properties from 300?K to 390?K. The fabric device can generate a TE voltage output (V) of 4.3?mV at a temperature difference (?T) of 75.2?K. The potential for using fabric TE devices to harvest body temperature energy has been discussed. Fabric-based TE devices may be useful for the development of new power generating clothing and self-powered wearable electronics. PMID:25804132

  16. Utilizing Radioisotope Power System Waste Heat for Spacecraft Thermal Management

    NASA Technical Reports Server (NTRS)

    Pantano, David R.; Dottore, Frank; Geng, Steven M.; Schrieber, Jeffrey G.; Tobery, E. Wayne; Palko, Joseph L.

    2005-01-01

    One of the advantages of using a Radioisotope Power System (RPS) for deep space or planetary surface missions is the readily available waste heat, which can be used to maintain electronic components within a controlled temperature range, to warm propulsion tanks and mobility actuators, and to gasify liquid propellants. Previous missions using Radioisotope Thermoelectric Generators (RTGs) dissipated a very large quantity of waste heat due to the relatively low efficiency of the thermoelectric conversion technology. The next generation RPSs, such as the 110-watt Stirling Radioisotope Generator (SRG110) will have much higher conversion efficiencies than their predecessors and therefore may require alternate approaches to transferring waste heat to the spacecraft. RTGs, with efficiencies of approx. 6 to 7% and 200 C housing surface temperatures, would need to use large and heavy radiator heat exchangers to transfer the waste heat to the internal spacecraft components. At the same time, sensitive spacecraft instruments must be shielded from the thermal radiation by using the heat exchangers or additional shields. The SRG110, with an efficiency around 22% and 50 C nominal housing surface temperature, can use the available waste heat more efficiently by more direct heat transfer methods such as heat pipes, thermal straps, or fluid loops. The lower temperatures allow the SRG110 much more flexibility to the spacecraft designers in configuring the generator without concern of overheating nearby scientific instruments, thereby eliminating the need for thermal shields. This paper will investigate using a high efficiency SRG110 for spacecraft thermal management and outline potential methods in several conceptual missions (Lunar Rover, Mars Rover, and Titan Lander) to illustrate the advantages with regard to ease of assembly, less complex interfaces, and overall mass savings.

  17. Thermal component models for electro thermal analysis of multichip power modules

    Microsoft Academic Search

    J. J. Rodriguez; Z. Parrilla; M. Velez-Reyes; A. Hefner; D. Berning; J. Reichl; J. Lai

    2002-01-01

    Thermal component models are developed for multi-chip of insulated gate bipolar transistor (IGBT) power electronic modules (PEM) and associated high-power converter heat sinks. The models are implemented in SABER and are combined with the electro-thermal IGBT and diode models to simulate the electro-thermal performance of high power converter systems. The thermal component models are parameterized in terms of structural and

  18. Biomass gasifier gas turbine power generating technology

    Microsoft Academic Search

    R. H. Williams; E. D. Larson

    1996-01-01

    Integrating gasifiers with gas turbines, aeroderivative gas turbines in particular, makes it possible to achieve high efficiencies and low unit capital costs in modest-scale biomass power generating facilities. Electricity produced with biomass-integrated gasifier\\/gas turbine (BIG\\/GT) power systems would be competitive with electricity produced from coal and nuclear energy under a wide range of circumstances. Biomass also offers major environmental benefits.

  19. Fiber-based flexible thermoelectric power generator

    Microsoft Academic Search

    A. Yadav; K. P. Pipe; M. Shtein

    2008-01-01

    Flexible thermoelectric power generators fabricated by evaporating thin films on flexible fiber substrates are demonstrated to be feasible candidates for waste heat recovery. An open circuit voltage of 19.6?VK per thermocouple junction is measured for Ni–Ag thin films, and a maximum power of 2nW for 7 couples at ?T=6.6K is measured. Heat transfer analysis is used to project performance for

  20. A thermoelectric generator using porous Si thermal isolation.

    PubMed

    Hourdakis, Emmanouel; Nassiopoulou, Androula G

    2013-01-01

    In this paper we report on a thermoelectric generator (TEG) using thermal isolation provided by a thick porous Si layer locally formed on the Si wafer and thermocouples composed of p-doped polycrystalline Si/Al. The "hot" contacts of the thermocouples lie on the porous Si layer, while the "cold" contacts lie on bulk crystalline Si. A housing was also designed and fabricated in order to transfer any external temperature change on the "hot" contacts of the thermocouples, the "cold" contacts being isolated from the "hot" contacts by a thick resist layer. The fabrication of the sensing element (Si die) is fully compatible with batch Si processing. The output power of the thermoelectric generator depends on the porous Si isolation layer thickness, porosity, structure and morphology. For a mesoporous Si layer of 60% porosity and a macroscopic temperature differential of 10 K, an output power of 0.39 ?W/cm2 was measured for a 50 ?m thick porous Si layer. PMID:24152923

  1. A Thermoelectric Generator Using Porous Si Thermal Isolation

    PubMed Central

    Hourdakis, Emmanouel; Nassiopoulou, Androula G.

    2013-01-01

    In this paper we report on a thermoelectric generator (TEG) using thermal isolation provided by a thick porous Si layer locally formed on the Si wafer and thermocouples composed of p-doped polycrystalline Si/Al. The “hot” contacts of the thermocouples lie on the porous Si layer, while the “cold” contacts lie on bulk crystalline Si. A housing was also designed and fabricated in order to transfer any external temperature change on the “hot” contacts of the thermocouples, the “cold” contacts being isolated from the “hot” contacts by a thick resist layer. The fabrication of the sensing element (Si die) is fully compatible with batch Si processing. The output power of the thermoelectric generator depends on the porous Si isolation layer thickness, porosity, structure and morphology. For a mesoporous Si layer of 60% porosity and a macroscopic temperature differential of 10 K, an output power of 0.39 ?W/cm2 was measured for a 50 ?m thick porous Si layer. PMID:24152923

  2. Research and Development for Novel Thermal Energy Storage Systems (TES) for Concentrating Solar Power (CSP)

    SciTech Connect

    Faghri, Amir; Bergman, Theodore L; Pitchumani, Ranga

    2013-09-26

    The overall objective was to develop innovative heat transfer devices and methodologies for novel thermal energy storage systems for concentrating solar power generation involving phase change materials (PCMs). Specific objectives included embedding thermosyphons and/or heat pipes (TS/HPs) within appropriate phase change materials to significantly reduce thermal resistances within the thermal energy storage system of a large-scale concentrating solar power plant and, in turn, improve performance of the plant. Experimental, system level and detailed comprehensive modeling approaches were taken to investigate the effect of adding TS/HPs on the performance of latent heat thermal energy storage (LHTES) systems.

  3. Optimisation of Concentrating Solar Thermal Power Plants with Neural Networks

    E-print Network

    Ábrahám, Erika

    Optimisation of Concentrating Solar Thermal Power Plants with Neural Networks Pascal Richter1 of solar power for energy supply is of in- creasing importance. While technical development mainly takes introduce our tool for the optimisation of parameterised solar thermal power plants, and report

  4. Value of Concentrating Solar Power and Thermal Energy Storage

    SciTech Connect

    Sioshansi, R.; Denholm, P.

    2010-02-01

    This paper examines the value of concentrating solar power (CSP) and thermal energy storage (TES) in four regions in the southwestern United States. Our analysis shows that TES can increase the value of CSP by allowing more thermal energy from a CSP plant?s solar field to be used, by allowing a CSP plant to accommodate a larger solar field, and by allowing CSP generation to be shifted to hours with higher energy prices. We analyze the sensitivity of CSP value to a number of factors, including the optimization period, price and solar forecasting, ancillary service sales, capacity value and dry cooling of the CSP plant. We also discuss the value of CSP plants and TES net of capital costs.

  5. Low thermal resistance power module assembly

    DOEpatents

    Hassani, Vahab (Denver, CO); Vlahinos, Andreas (Castle Rock, CO); Bharathan, Desikan (Arvada, CO)

    2010-12-28

    A power module assembly (400) with low thermal resistance and enhanced heat dissipation to a cooling medium. The assembly includes a heat sink or spreader plate (410) with passageways or openings (414) for coolant that extend through the plate from a lower surface (411) to an upper surface (412). A circuit substrate (420) is provided and positioned on the spreader plate (410) to cover the coolant passageways. The circuit substrate (420) includes a bonding layer (422) configured to extend about the periphery of each of the coolant passageways and is made up of a substantially nonporous material. The bonding layer (422) may be solder material which bonds to the upper surface (412) of the plate to provide a continuous seal around the upper edge of each opening (414) in the plate. The assembly includes power modules (430) mounted on the circuit substrate (420) on a surface opposite the bonding layer (422). The power modules (430) are positioned over or proximal to the coolant passageways.

  6. New Generation Perovskite Thermal Barrier Coating Materials

    NASA Astrophysics Data System (ADS)

    Ma, W.; Jarligo, M. O.; Mack, D. E.; Pitzer, D.; Malzbender, J.; Vaßen, R.; Stöver, D.

    2008-12-01

    Advanced ceramic materials of perovskite structure have been developed for potential application in thermal barrier coating systems, in an effort to improve the properties of the pre-existing ones like yttria-stabilized zirconia. Yb2O3 and Gd2O3 doped strontium zirconate (SrZrO3) and barium magnesium tantalate (Ba(Mg1/3Ta2/3)O3) of the ABO3 and complex A(B'1/3B''2/3)O3 systems, respectively, have been synthesized using ball milling prior to solid state sintering. Thermal and mechanical investigations show desirable properties for high-temperature coating applications. On atmospheric plasma spraying, the newly developed thermal barrier coatings reveal promising thermal cycle lifetime up to 1350 °C.

  7. Radioisotope space power generators: Design concepts

    NASA Astrophysics Data System (ADS)

    Forsman, Tina; Simion, George

    The use of radioisotope power systems for space applications was a key part of some of the most ambitious astronautical undertakings of the United States. Nuclear power sources have provided the electrical energy for the NASA Pioneer, Viking, and Voyager missions as well as earlier earth orbital and Apollo missions. Recently developed, radioisotope thermoelectric generators (RTGs) will be used in future space missions, such as the Galileo Project (Jupiter study) and the International Solar Polar Mission. Present design concepts of RTGs and related dynamic isotope power systems (DIPS) are surveyed.

  8. Selection and development of small solar thermal power applications

    NASA Technical Reports Server (NTRS)

    Bluhm, S. A.; Kuehn, T. J.; Gurfield, R. M.

    1979-01-01

    The paper discusses the approach of the JPL Point Focusing Thermal and Electric Power Applications Project to selecting and developing applications for point-focusing distributed-receiver solar thermal electric power systems. Six application categories are defined. Results of application studies of U.S. utilities are presented. The economic value of solar thermal power systems was found to range from $900 to $2100/kWe in small community utilities of the Southwest.

  9. Electric power output optimization in Seebeck generators: Beyond high ZT

    NASA Astrophysics Data System (ADS)

    Narducci, Dario

    2012-06-01

    The possibility of enhancing the thermoelectric figure of merit ZT by damping the material thermal conductivity (e.g. by quantum confinement) rather than by increasing its power factor has generated a surge of interest toward the use of nanostructures in thermoelectric generators (TEGs). Actually, while ZT is an appropriate performance index when optimizing the rate of heat conversion in the presence of small thermal power inputs, it may turn out to be misleading when used as a general criterion. Under fixed heat flow conditions, the optimization of ZT may actually proceed only by maximizing the power factor, since materials with low ? may be unable to duly dissipate heat. However, also when operating between heat reservoirs at fixed temperature it is shown that the highest electric power a TEG can output may be obtained by increasing ?, not decreasing it. In addition, it will be presented an equation allowing to determine the TE efficiency over temperature ranges where transport parameters are no longer temperature-independent.

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

    SciTech Connect

    Pitts, J.H.

    1986-07-31

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

  11. Energy storage and thermal control system design status. [for space station power supplies

    NASA Technical Reports Server (NTRS)

    Simons, Stephen N.; Willhoite, Bryan C.; Van Ommering, Gert

    1989-01-01

    The Space Station Freedom electric power system (EPS) will initially rely on photovoltaics for power generation and Ni/H2 batteries for electrical energy storage. The current design for the development status of two major subsystems in the PV Power Module is discussed. The energy storage subsystem comprised of high capacity Ni/H2 batteries and the single-phase thermal control system that rejects the excess heat generated by the batteries and other components associated with power generation andstorage is described.

  12. Thermal Powered Reciprocating-Force Motor

    NASA Technical Reports Server (NTRS)

    Tatum, III, Paul F. (Inventor); McDow Elliott, Amelia (Inventor)

    2015-01-01

    A thermal-powered reciprocating-force motor includes a shutter switchable between a first position that passes solar energy and a second position that blocks solar energy. A shape memory alloy (SMA) actuator is coupled to the shutter to control switching thereof between the shutter's first and second position. The actuator is positioned with respect to the shutter such that (1) solar energy impinges on the SMA when the shutter is in its first position so that the SMA experiences contraction in length until the shutter is switched to its second position, and (2) solar energy is impeded from impingement on the SMA when the shutter is in its second position so that the SMA experiences extension in length. Elastic members coupled to the actuator apply a force to the SMA that aids in its extension in length until the shutter is switched to its first position.

  13. Global Climate Change - The Power Generation Challenge

    EPA Science Inventory

    The planet continues to warm; O.5 C from the 1970’s to the 2000’s. Also, worldwide CO2 emissions have increased at a 3% annual growth rate from 2000 to 2010. Such emissions are driven by fossil fuel combustion, especially in the power generation sector, & especial...

  14. Power generation with synthetic liquid fuels

    Microsoft Academic Search

    1984-01-01

    The authors report combustion tests in full-scale utility power generation equipment using Exxon Donor Solvent coal liquids and H-Coal liquids. Details of the tests are given and results are presented. It was shown that the coal liquids could be used as turbine fuels with 1800 F or higher firing temperatures. Additional industrial hygiene precautions were taken to ensure minimum crew

  15. Cascading Closed Loop Cycle Power Generation 

    E-print Network

    Romero, M.

    2008-01-01

    WOW Energies was issued Patent 6,857,268 B2 on Feb 22, 2005 titled “CASCADING CLOSED LOOP CYCLE (CCLC) and Patent 7,096,665 B2 on August 29, 2006 titled “CASCADING CLOSED LOOP CYCLE POWER GENERATION”. These patented technologies are collectively...

  16. Solid Oxide Fuel Cell Power Generation Systems

    SciTech Connect

    Singh, Prabhakar; Pederson, Larry R.; Simner, Steve P.; Stevenson, Jeffry W.; Viswanathan, Vish V.

    2001-05-12

    An increasing worldwide demand for premium power, emerging trend towards electric utility deregulation and distributed power generation, global environmental concerns and regulatory controls have accelerated the development of advanced fuel cell based power generation systems. Fuel cells convert chemical energy to electrical energy through electrochemical oxidation of gaseous and/or liquid fuels ranging from hydrogen to hydrocarbons. Electrochemical oxidation of fuels prevents the formation of Nox, while the higher efficiency of the systems reduces carbon dioxide emissions (kg/kWh). Among various fuel cell power generation systems currently being developed for stationary and mobile applications, solid oxide fuel cells (SOFC) offer higher efficiency (up to 80% overall efficiency in hybrid configurations), fuel flexibility, tolerance to CO poisoning, modularity, and use of non-noble construction materials of low strategic value. Tubular, planar, and monolithic cell and stack configurations are currently being developed for stationary and military applications. The current generation of fuel cells uses doped zirconia electrolyte, nickel cermet anode, doped Perovskite cathode electrodes and predominantly ceramic interconnection materials. Fuel cells and cell stacks operate in a temperature range of 800-1000 *C. Low cost ($400/kWe), modular (3-10kWe) SOFC technology development approach of the Solid State Energy Conversion Alliance (SECA) initiative of the USDOE will be presented and discussed. SOFC technology will be reviewed and future technology development needs will be addressed.

  17. Opportunities in photovoltaics for space power generation

    Microsoft Academic Search

    D. C. Senft; Kirtland AFB

    2005-01-01

    Photovoltaics provide virtually all power generation for space systems, and the majority of these, in recent years, are multijunction solar cells comprised of III-V materials. Multijunction solar cells are designed for optimal efficiency under the space AM0 (Air Mass Zero) solar spectrum and to operate with high reliability under hostile environmental conditions. State of practice crystalline multijunction solar cells are

  18. Generation of Powerful Ultrashort Microwave Pulses

    Microsoft Academic Search

    A. A. Eltchaninov; S. D. Korovin; I. V. Pegel; V. V. Rostov; M. I. Yalandin

    2003-01-01

    We study theoretically and experimentally the possibility of generation of ultrashort powerful microwave pulses. The regime of spatial accumulation of electromagnetic energy is considered in the case where the pulse propagates oppositely to the electron flow in a long slow-wave structure. We show that during transformation of the kinetic energy of electrons to the energy of an electromagnetic pulse, the

  19. Thermoelectric unicouple used for power generation

    NASA Technical Reports Server (NTRS)

    Caillat, Thierry (Inventor); Zoltan, Andrew (Inventor); Zoltan, Leslie (Inventor); Snyder, Jeffrey (Inventor)

    2004-01-01

    A high-efficiency thermoelectric unicouple is used for power generation. The unicouple is formed with a plurality of legs, each leg formed of a plurality of segments. The legs are formed in a way that equalizes certain aspects of the different segments. Different materials are also described.

  20. Thermal analyses of power subsystem components

    NASA Technical Reports Server (NTRS)

    Morehouse, Jeffrey H.

    1990-01-01

    The hiatus in the Space Shuttle (Orbiter) program provided time for an in-depth examination of all the subsystems and their past performance. Specifically, problems with reliability and/or operating limits were and continue to be of major engineering concern. The Orbiter Auxiliary Power Unit (APU) currently operates with electric resistance line heaters which are controlled with thermostats. A design option simplification of this heater subsystem is being considered which would use self-regulating heaters. A determination of the properties and thermal operating characteristics of these self-regulating heaters was needed. The Orbiter fuel cells are cooled with a freon loop. During a loss of external heat exchanger coolant flow, the single pump circulating the freon is to be left running. It was unknown what temperature and flow rate transient conditions of the freon would provide the required fuel cell cooling and for how long. The overall objective was the development of the thermal characterization and subsequent analysis of both the proposed self-regulating APU heater and the fuel cell coolant loop subsystem. The specific objective of the APU subsystem effort was to determine the feasibility of replacing the current heater and thermostat arrangement with a self-regulating heater. The specific objective of the fuel cell coolant subsystem work was to determine the tranient coolant temperature and associated flow rates during a loss-of-external heat exchanger flow.

  1. Recent advances in RF power generation

    SciTech Connect

    Tallerico, P.J.

    1990-01-01

    This paper is a review of the progress and methods used in RF generation for particle accelerators. The frequencies of interest are from a few megahertz to 100 GHz, and the powers are for super linear collider applications, but in this case the pulses are short, generally below 1 {mu}s. The very high-power, short-pulse generators are only lightly reviewed here, and for more details the reader should follow the specialized references. Different RF generators excel over various parts of the frequency spectrum. Below 100 MHz solid-state devices and gridded tubes prevail, while the region between 400 MHz and 3 GHz, the cyclotron-resonant devices predominate, and above 250 GHz, Free-Electron Lasers and ubitrons are the most powerful generators. The emphasis for this review is on microwave generation at frequencies below 20 GHz, so the cyclotron-resonant devices are only partially reviewed, while the progress on free-electron laser and ubitrons is not reviewed in this paper. 39 refs., 4 figs.

  2. Thermoelectric power generation system optimization studies

    NASA Astrophysics Data System (ADS)

    Karri, Madhav A.

    A significant amount of energy we consume each year is rejected as waste heat to the ambient. Conservative estimates place the quantity of energy wasted at about 70%. Converting the waste heat into electrical power would be convenient and effective for a number of primary and secondary applications. A viable solution for converting waste heat into electrical energy is to use thermoelectric power conversion. Thermoelectric power generation is based on solid state technology with no moving parts and works on the principle of Seebeck effect. In this work a thermoelectric generator (TEG) system simulator was developed to perform various parametric and system optimization studies. Optimization studies were performed to determine the effect of system size, exhaust and coolant ow conditions, and thermoelectric material on the net gains produced by the TEG system and on the optimum TEG system design. A sports utility vehicle was used as a case study for the application of TEG in mobile systems.

  3. Optical generation of radio-frequency power

    NASA Astrophysics Data System (ADS)

    Hietala, V. M.; Vawter, G. A.; Brennan, T. M.; Hammons, B. E.; Meyer, W. J.

    1994-11-01

    An optical technique for high-power radio-frequency (RF) signal generation is described. The technique uses a unique photodetector based on a traveling-wave design driven by an appropriately modulated light source. The traveling-wave photodetector (TWPD) exhibits simultaneously a theoretical quantum efficiency approaching 100% and a very large electrical bandwidth. Additionally, it is capable of dissipating the high-power levels required for the RF generation technique. The modulated light source is formed by either the beating together of two lasers or by the direct modulation of a light source. A system example is given which predicts RF power levels of 100's of mW's at millimeter wave frequencies with a theoretical 'wall-plug' efficiency approaching 34%.

  4. Optical generation of radio-frequency power

    SciTech Connect

    Hietala, V.M.; Vawter, G.A.; Brennan, T.M.; Hammons, B.E.; Meyer, W.J.

    1994-11-01

    An optical technique for high-power radio-frequency (RF) signal generation is described. The technique uses a unique photodetector based on a traveling-wave design driven by an appropriately modulated light source. The traveling-wave photodetector (TWPD) exhibits simultaneously a theoretical quantum efficiency approaching 100 % and a very large electrical bandwidth. Additionally, it is capable of dissipating the high-power levels required for the RF generation technique. The modulated light source is formed by either the beating together of two lasers or by the direct modulation of a light source. A system example is given which predicts RF power levels of 100`s of mW`s at millimeter wave frequencies with a theoretical ``wall-plug`` efficiency approaching 34%.

  5. Evaluation of solar thermal storage for base load electricity generation

    NASA Astrophysics Data System (ADS)

    Adinberg, R.

    2012-10-01

    In order to stabilize solar electric power production during the day and prolong the daily operating cycle for several hours in the nighttime, solar thermal power plants have the options of using either or both solar thermal storage and fossil fuel hybridization. The share of solar energy in the annual electricity production capacity of hybrid solar-fossil power plants without energy storage is only about 20%. As it follows from the computer simulations performed for base load electricity demand, a solar annual capacity as high as 70% can be attained by use of a reasonably large thermal storage capacity of 22 full load operating hours. In this study, the overall power system performance is analyzed with emphasis on energy storage characteristics promoting a high level of sustainability for solar termal electricity production. The basic system parameters, including thermal storage capacity, solar collector size, and annual average daily discharge time, are presented and discussed.

  6. Photovoltaic Power Generation in the Stellar Environments

    E-print Network

    Girish, T E

    2010-01-01

    In this paper we have studied the problem of photovoltaic power generation near selected stars in the solar neighborhood. The nature of the optical radiation from a star will depend on its luminosity,HR classification and spectral characteristics. The solar celloperation in the habitable zones of the stars is similar to AM1.0 operation near earth.Thecurrent space solar cell technology can be adopted for power generation near G,K and Mtype stars. Silicon solar cells with good near IR response are particularly suitable in theenvironments of M type stars which are most abundant in the universe. . Photovoltaicpower generation near binary stars like Sirius and Alpha Centauri is also discussed.

  7. Photovoltaic Power Generation in the Stellar Environments

    E-print Network

    T. E. Girish; S. Aranya

    2010-12-03

    In this paper we have studied the problem of photovoltaic power generation near selected stars in the solar neighborhood. The nature of the optical radiation from a star will depend on its luminosity,HR classification and spectral characteristics. The solar celloperation in the habitable zones of the stars is similar to AM1.0 operation near earth.Thecurrent space solar cell technology can be adopted for power generation near G,K and Mtype stars. Silicon solar cells with good near IR response are particularly suitable in theenvironments of M type stars which are most abundant in the universe. . Photovoltaicpower generation near binary stars like Sirius and Alpha Centauri is also discussed.

  8. Transient Non-linear Thermal FEM Simulation of Smart Power Switches and Verification by Measurements

    E-print Network

    V. Kosel; R. Sleik; M. Glavanovics

    2008-01-07

    Thermal FEM (Finite Element Method) simulations can be used to predict the thermal behavior of power semiconductors in application. Most power semiconductors are made of silicon. Silicon thermal material properties are significantly temperature dependent. In this paper, validity of a common non-linear silicon material model is verified by transient non-linear thermal FEM simulations of Smart Power Switches and measurements. For verification, over-temperature protection behavior of Smart Power Switches is employed. This protection turns off the switch at a pre-defined temperature which is used as a temperature reference in the investigation. Power dissipation generated during a thermal overload event of two Smart Power devices is measured and used as an input stimulus to transient thermal FEM simulations. The duration time of the event together with the temperature reference is confronted with simulation results and thus the validity of the silicon model is proved. In addition, the impact of non-linear thermal properties of silicon on the thermal impedance of power semiconductors is shown.

  9. Thermal memory effects modeling and compensation in RF power amplifiers and predistortion linearizers

    Microsoft Academic Search

    Slim Boumaiza; Fadhel M. Ghannouchi

    2003-01-01

    Memory effects, which influence the performance of RF power amplifiers (PAs) and predistortion-based linearizers, become more significant and critical in designing these circuits as the modulation signal bandwidth and operation power increase. This paper reports on an attempt to investigate, model, and quantify the contributions of the electrical nonlinearity effects and the thermal memory effects to a PA's distortion generation,

  10. Worker health and safety in solar thermal power systems. IV. Routine failure hazards

    Microsoft Academic Search

    A. Z. Ullman; B. B. Sokolow; J. Hill; G. Meunier; H. Busick

    1979-01-01

    Routine failure events in selected solar thermal power system designs are examined, and their rates of occurrence estimated. The results are used to compare and rank the systems considered. Modules of 1 to 100 MWe are developed based on reference or other near-term designs. Technologies used include parabolic trough, parabolic dish, and central tower focusing; central and distributed power generation;

  11. Thermoelectric power generation for hybrid-electric vehicle auxiliary power

    NASA Astrophysics Data System (ADS)

    Headings, Leon M.; Washington, Gregory N.; Midlam-Mohler, Shawn; Heremans, Joseph P.

    2009-03-01

    The plug-in hybrid-electric vehicle (PHEV) concept allows for a moderate driving range in electric mode but uses an onboard range extender to capitalize on the high energy density of fuels using a combustion-based generator, typically using an internal combustion engine. An alternative being developed here is a combustion-based thermoelectric generator in order to develop systems technologies which capitalize on the high power density and inherent benefits of solid-state thermoelectric power generation. This thermoelectric power unit may find application in many military, industrial, and consumer applications including range extension for PHEVs. In this research, a baseline prototype was constructed using a novel multi-fuel atomizer with diesel fuel, a conventional thermoelectric heat exchange configuration, and a commercially available bismuth telluride module (maximum 225°C). This prototype successfully demonstrated the viability of diesel fuel for thermoelectric power generation, provided a baseline performance for evaluating future improvements, provided the mechanism to develop simulation and analysis tools and methods, and highlighted areas requiring development. The improvements in heat transfer efficiency using catalytic combustion were evaluated, the system was redesigned to operate at temperatures around 500 °C, and the performance of advanced high temperature thermoelectric modules was examined.

  12. Modeling of solar thermal selective surfaces and thermoelectric generators

    E-print Network

    McEnaney, Kenneth

    2010-01-01

    A thermoelectric generator is a solid-state device that converts a heat flux into electrical power via the Seebeck effect. When a thermoelectric generator is inserted between a solar-absorbing surface and a heat sink, a ...

  13. Standard Guide for Specifying Thermal Performance of Geothermal Power Systems

    E-print Network

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This guide covers power plant performance terms and criteria for use in evaluation and comparison of geothermal energy conversion and power generation systems. The special nature of these geothermal systems makes performance criteria commonly used to evaluate conventional fossil fuel-fired systems of limited value. This guide identifies the limitations of the less useful criteria and defines an equitable basis for measuring the quality of differing thermal cycles and plant equipment for geothermal resources. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  14. Fresnel Concentrators for Space Solar Power and Solar Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Bradford, Rodney; Parks, Robert W.; Craig, Harry B. (Technical Monitor)

    2001-01-01

    Large deployable Fresnel concentrators are applicable to solar thermal propulsion and multiple space solar power generation concepts. These concentrators can be used with thermophotovoltaic, solar thermionic, and solar dynamic conversion systems. Thin polyimide Fresnel lenses and reflectors can provide tailored flux distribution and concentration ratios matched to receiver requirements. Thin, preformed polyimide film structure components assembled into support structures for Fresnel concentrators provide the capability to produce large inflation-deployed concentrator assemblies. The polyimide film is resistant to the space environment and allows large lightweight assemblies to be fabricated that can be compactly stowed for launch. This work addressed design and fabrication of lightweight polyimide film Fresnel concentrators, alternate materials evaluation, and data management functions for space solar power concepts, architectures, and supporting technology development.

  15. Design and economy of solar power plants with integrated thermal energy storage

    Microsoft Academic Search

    P. V. Gilli; G. Beckmann

    1977-01-01

    Due to discrepancies of electric supply and demand patterns in solar steam power plants, energy storage - either integrated thermal energy storage (before generator), pumped hydro storage (after generator, before meter), or storage at the customer (after meter) - is required. Steam storage requires pressure vessels and is limited in temperature, but oil or fused salt are more expensive and

  16. Nonlinear Generation of Electromagnetic Waves Through Scattering by Thermal Electrons

    NASA Astrophysics Data System (ADS)

    Tejero, E. M.; Crabtree, C. E.; Blackwell, D. D.; Amatucci, B.; Mithaiwala, M.; Rudakov, L.; Ganguli, G.

    2014-12-01

    Nonlinear interactions involving whistler wave turbulence are important contributors to radiation belt dynamics, including the acceleration and loss of trapped electrons. Given sufficient whistler energy density, nonlinear scattering from thermal electrons can substantially change the wave normal angle, while inducing a small frequency shift [Ganguli et al., 2010]. This nonlinear process is being studied in the NRL Space Physics Simulation Chamber (SPSC) in scaled magnetospheric conditions. The plasma response as a function of transmitted lower hybrid wave amplitude is monitored with magnetic loop antennas. Measurements of the magnetic field vectors for the pump and daughter waves allow for the determination of wave distribution functions, which indicate the power distribution as a function of wave-normal angle and azimuthal angle. The wave distribution functions measured in the experiment demonstrate a dramatic change in propagation direction when the launched wave amplitude exceeds a small threshold (?B / B ~ 4 × 10-7). The experimental results support the theory of electromagnetic whistler wave generation through nonlinear scattering of electrostatic lower hybrid waves by thermal electrons in the Earth's magnetosphere [Crabtree et al, 2012].

  17. DOWNHOLE POWER GENERATION AND WIRELESS COMMUNICATIONS

    SciTech Connect

    Paul Tubel

    2003-04-24

    The second quarter of the project was dedicated to convert the conceptual designs for the wireless tool and power generator into mechanical and electrical drawings as well as software code to create the new system. The tasks accomplished during this report period were: (1) Basic mechanical design for the wireless communications system was created and the detailed drawings were started. (2) Basic design for the power generator system was created and the detailed machining drawings were started. The generator design was modified to provide a direct action between the wellbore fluid flow and the piezoelectric stack to generate energy. The new design eliminates the inefficiencies related to picking up outside the tubing wall the pressure fluctuations occurring inside the tubing walls. (3) The new piezoelectric acoustic generator design was created and ordered from the manufacturer. The system will be composed of 40 ceramic wafers electrically connected in parallel and compressed into a single generator assembly. (4) The acoustic two-way communications requirements were also defined and the software and hardware development were started. (5) The electrical hardware development required to transmit information to the surface and to receive commands from the surface was started.

  18. Experimental demonstration of thermal management using thermoelectric generation

    Microsoft Academic Search

    Gary L. Solbrekken; Kazuaki Yazawa; Avram Bar-Cohen

    2004-01-01

    It has been well established that thermal management of electronic equipment is a critical need for the continued success of the microelectronics industry. Portable electronic devices, such as notebook computers and cellular telephones, require that the thermal solution be small, light, and energy efficient. Small-scale thermoelectric (TE) modules can be used to generate electricity from the waste heat of the

  19. Output power analyses for the thermodynamic cycles of thermal power plants

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  20. The New Generation of Thermal Mapping

    ERIC Educational Resources Information Center

    Patterson, Valerie B.

    2012-01-01

    Thermal imaging was used 60+ years ago to enable the targeting of heat-seeking missiles and seeing opposing forces at night. Today thermograpy is employed for myriad uses, from turning on faucets, to tracking and attacking enemies from aerial spy drones, to identifying the scope of moisture infiltration in building envelopes. Thermography for…

  1. Evaluation of solar aided biomass power generation systems with parabolic trough field

    Microsoft Academic Search

    HongJuan Hou; YongPing Yang; Eric Hu; JiFeng Song; ChangQing Dong; Jian Mao

    2011-01-01

    Solar and biomass are both renewable energy resources. Using biomass as fuel is becoming more and more attractive after governments\\u000a increase the tariff for the electricity from the renewable sources. However the costs of power from a biomass power generation\\u000a plant depend greatly on the availability and quality of the biomass resource. The commercialization of solar alone thermal\\u000a power generation

  2. Application of Organic Rankine Cycles (ORCs) to decentralized power generation, preliminary study

    Microsoft Academic Search

    Reino Huovilainen; Jarmo Alamaeki; Risto Tarjanne

    1987-01-01

    The study concentrates on MW-class ORC processes that could be utilized in connection with different kind of power plants. The use of an ORC-process may offer potential for improvements in two ways; first, an ORC-process can be suitable with low-grade thermal sources where water based power generation is not feasible. Second, an increase in power generation efficiency is achieved. The

  3. Isotope powered Stirling generator for terrestrial applications

    SciTech Connect

    Tingey, G.L.; Sorensen, G.C. [Pacific Northwest Lab., Richland, WA (United States); Ross, B.A. [Stirling Technology Co., Richland, WA (United States)

    1995-01-01

    An electric power supply, small enough to be man-portable, is being developed for remote, terrestrial applications. This system is designed for an operating lifetime of five years without maintenance or refueling. A small Radioisotope Stirling Generator (RSG) has been developed. The energy source of the generator is a 60 watt plutonium-238 fuel clad used in the General Purpose Heat Sources (GPHS) developed for space applications. A free piston Stirling Engine drives a linear alternator to convert the heat to power. The system weighs about 7.5 kg and produces 11 watts AC power with a conversion efficiency of 18.5%. Two engine models have been designed, fabricated, and tested to date: (a) a developmental model instrumented to confirm and test parameters, and (b) an electrically heated model with an electrical heater equipped power input leads. Critical components have been tested for 10,000 to 20,000 hours. One complete generator has been operating for over 11,000 hours. Radioisotope heated prototypes are expected to be fabricated and tested in late 1995.

  4. Coal Gasification for Power Generation, 3. edition

    SciTech Connect

    NONE

    2007-11-15

    The report provides a concise look at the challenges faced by coal-fired generation, the ability of coal gasification to address these challenges, and the current state of IGCC power generation. Topics covered include: an overview of Coal Generation including its history, the current market environment, and the status of coal gasification; a description of gasification technology including processes and systems; an analysis of the key business factors that are driving increased interest in coal gasification; an analysis of the barriers that are hindering the implementation of coal gasification projects; a discussion of Integrated Gasification Combined Cycle (IGCC) technology; an evaluation of IGCC versus other generation technologies; a discussion of IGCC project development options; a discussion of the key government initiatives supporting IGCC development; profiles of the key gasification technology companies participating in the IGCC market; and, a detailed description of existing and planned coal IGCC projects.

  5. A thermal signal generator probe for the study of neural thermal transduction.

    PubMed

    Maluf, N I; McNutt, E L; Monroe, S; Tanelian, D L; Kovacs, G T

    1994-07-01

    The study of thermal transduction in neural tissues has been impeded by the lack of instrumentation able to generate complex, focal temperature variations. Specifically, we are interested in the study of neural thermal transduction within the cornea, with its homogeneous thermal conductivity and avascularity. We present a thermal signal generator probe that is capable of producing arbitrarily shaped bipolar (heating or cooling) thermal swings in a small volume of corneal tissue with which it is in contact. Heating and cooling of the probe tip are achieved by means of a Peltier effect thermoelectric device. The probe temperature, measured directly at the tip, is controlled using closed-loop control circuitry and waveform generation software on a host computer. Response characteristics of thermally sensitive C-fibers were investigated in an in vitro preparation of the rabbit cornea. PMID:7927385

  6. Electrokinetic Power Generation from Liquid Water Microjets

    SciTech Connect

    Duffin, Andrew M.; Saykally, Richard J.

    2008-02-15

    Although electrokinetic effects are not new, only recently have they been investigated for possible use in energy conversion devices. We have recently reported the electrokinetic generation of molecular hydrogen from rapidly flowing liquid water microjets [Duffin et al. JPCC 2007, 111, 12031]. Here, we describe the use of liquid water microjets for direct conversion of electrokinetic energy to electrical power. Previous studies of electrokinetic power production have reported low efficiencies ({approx}3%), limited by back conduction of ions at the surface and in the bulk liquid. Liquid microjets eliminate energy dissipation due to back conduction and, measuring only at the jet target, yield conversion efficiencies exceeding 10%.

  7. Numerical simulations of a low power microchannel thermal cycling reactor

    E-print Network

    Erickson, David

    of low cost batteries. In this study, a microchannel thermal cycling reactor design using inNumerical simulations of a low power microchannel thermal cycling reactor David Erickson, Dongqing were conducted to determine the conditions under which efficient, rapid thermal cycling can be achieved

  8. Tritium labeling by thermally generated tritons

    SciTech Connect

    Morimoto, H.; Williams, P.G.; Saljoughian, M.

    1988-06-01

    The predominant effect of thermal atom irradiation on solid molecules is saturation of their aromatic functions. Only low level of tritium exchange is observed for aliphatic solids. In contrast, liquids whose frozen surface can be rendered somewhat mobile at appropriate temperatures exhibit more exchange than addition. The rank order of effectiveness of several metals in promoting exchange/addition appears similar to the rank order for heterogeneous catalytic hydrogenation. 3 refs., 8 figs.

  9. Utilizing Radioisotope Power System Waste Heat for Spacecraft Thermal Management

    NASA Technical Reports Server (NTRS)

    Pantano, David R.; Dottore, Frank; Tobery, E. Wayne; Geng, Steven M.; Schreiber, Jeffrey G.; Palko, Joseph L.

    2005-01-01

    An advantage of using a Radioisotope Power System (RPS) for deep space or planetary surface missions is the readily available waste heat, which can be used for a number of beneficial purposes including: maintaining electronic components within a controlled temperature range, warming propulsion tanks and mobility actuators, and maintaining liquid propellants above their freezing temperature. Previous missions using Radioisotope Thermoelectric Generators (RTGs) dissipated large quantities of waste heat due to the low efficiency of the thermoelectric conversion technology. The next generation RPSs, such as the 110-Watt Stirling Radioisotope Generator (SRG110) will have higher conversion efficiencies, thereby rejecting less waste heat at a lower temperature and may require alternate approaches to transferring waste heat to the spacecraft. RTGs, with efficiencies of 6 to 7 percent, reject their waste heat at the relatively high heat rejection temperature of 200 C. This is an advantage when rejecting heat to space; however, transferring heat to the internal spacecraft components requires a large and heavy radiator heat exchanger. At the same time, sensitive spacecraft instruments must be shielded from the thermal radiation of the RTG. The SRG110, with an efficiency around 22 percent and 50 C nominal housing surface temperature, can readily transfer the available waste heat directly via heat pipes, thermal straps, or fluid loops. The lower temperatures associated with the SRG110 avoid the chances of overheating other scientific components, eliminating the need for thermal shields. This provides the spacecraft designers more flexibility when locating the generator for a specific mission. A common misconception with high-efficiency systems is that there is not enough waste heat for spacecraft thermal management. This paper will dispel this misconception and investigate the use of a high-efficiency SRG110 for spacecraft thermal management and outline potential methods of waste heat utilization in several conceptual missions (Lunar Rover, Mars Rover, and Titan Lander). The advantages associated with the SRG110 as they relate to ease of assembly, less complex interfaces, and overall mass savings for a spacecraft will be highlighted.

  10. Utility scale hybrid wind–solar thermal electrical generation: A case study for Minnesota

    Microsoft Academic Search

    J. P. Reichling; F. A. Kulacki

    2008-01-01

    The performance of a hybrid wind–solar power plant in southwestern Minnesota is modeled for a 2-yr period using hourly wind and solar insolation data. The wind portion of the plant consists of four interconnected wind farms within a radius of 90km. The solar component of the plant is a parabolic trough solar thermal electric generating system using a heat transfer

  11. COUPLING SUPERCRITICAL AND SUPERHEATED DIRECT STEAM GENERATION WITH THERMAL ENERGY STORAGE

    E-print Network

    COUPLING SUPERCRITICAL AND SUPERHEATED DIRECT STEAM GENERATION WITH THERMAL ENERGY STORAGE Joe storage system. The use of both supercritical and superheated subcritical steam is proposed, and discussed the supercritical and subcritical cases. For the power cycle, it was shown that there are advantages in using

  12. High thermal power density heat transfer. [thermionic converters

    NASA Technical Reports Server (NTRS)

    Morris, J. F. (inventor)

    1980-01-01

    Heat from a high temperature heat pipe is transferred through a vacuum or a gap filled with electrically nonconducting gas to a cooler heat pipe. The heat pipe is used to cool the nuclear reactor while the heat pipe is connected thermally and electrically to a thermionic converter. If the receiver requires greater thermal power density, geometries are used with larger heat pipe areas for transmitting and receiving energy than the area for conducting the heat to the thermionic converter. In this way the heat pipe capability for increasing thermal power densities compensates for the comparatively low thermal power densities through the electrically non-conducting gap between the two heat pipes.

  13. Thermal-To-Electric Converter With Greater Power Density

    NASA Technical Reports Server (NTRS)

    Williams, Roger M.; Suitor, Jerry W.; Jeffries-Nakamura, Barbara; Underwood, Mark L.; Ryan, Margaret A.; O'Connor, Dennis

    1992-01-01

    Proposed design for alkali-metal thermal-to-electric converter (AMTEC) incorporates refinements to increase power density and reduce input temperature below typical prior design. Converter has compact, planar configuration. Cells stacked densely with remote condenser for thermal efficiency and high power density. Either liquid- or vapor-fed cells utilized. Heat fed-in at lower temperature.

  14. Exergetic analysis of a solar thermal power system

    Microsoft Academic Search

    Narendra Singh; S. C. Kaushik; R. D. Misra

    2000-01-01

    This communication presents a second law analysis based on an exergy concept for a solar thermal power system. Basic energy and exergy analysis for the system components (viz. parabolic trough collector\\/receiver and Rankine heat engine, etc.) are carried out for evaluating the respective losses as well as exergetic efficiency for typical solar thermal power systems under given operating conditions. It

  15. Model for Increasing the Power Obtained from a Thermoelectric Generator Module

    NASA Astrophysics Data System (ADS)

    Huang, Gia-Yeh; Hsu, Cheng-Ting; Yao, Da-Jeng

    2014-06-01

    We have developed a model for finding the most efficient way of increasing the power obtained from a thermoelectric generator (TEG) module with a variety of operating conditions and limitations. The model is based on both thermoelectric principles and thermal resistance circuits, because a TEG converts heat into electricity consistent with these two theories. It is essential to take into account thermal contact resistance when estimating power generation. Thermal contact resistance causes overestimation of the measured temperature difference between the hot and cold sides of a TEG in calculation of the theoretical power generated, i.e. the theoretical power is larger than the experimental power. The ratio of the experimental open-loop voltage to the measured temperature difference, the effective Seebeck coefficient, can be used to estimate the thermal contact resistance in the model. The ratio of the effective Seebeck coefficient to the theoretical Seebeck coefficient, the Seebeck coefficient ratio, represents the contact conditions. From this ratio, a relationship between performance and different variables can be developed. The measured power generated by a TEG module (TMH400302055; Wise Life Technology, Taiwan) is consistent with the result obtained by use of the model; the relative deviation is 10%. Use of this model to evaluate the most efficient means of increasing the generated power reveals that the TEG module generates 0.14 W when the temperature difference is 25°C and the Seebeck coefficient ratio is 0.4. Several methods can be used triple the amount of power generated. For example, increasing the temperature difference to 43°C generates 0.41 W power; improving the Seebeck coefficient ratio to 0.65 increases the power to 0.39 W; simultaneously increasing the temperature difference to 34°C and improving the Seebeck coefficient ratio to 0.5 increases the power to 0.41 W. Choice of the appropriate method depends on the limitations of system, the cost, and the environment.

  16. Simulation of Piezoelectric Jellyfish Power Generator

    NASA Astrophysics Data System (ADS)

    Wu, Yeong-Jen; Lai, Wei-Hsiang

    The energy problem is getting increasingly serious. As such, unused energy recovery technology is crucial for environmental protection, which has been investigated extensively. Several methods have been developed to utilize scavenged energy from the environment, such as waste heat, solar energy, wind energy, and tides energy to convert into useful power. There is a new idea of piezoelectric jellyfish generator which combines the utilization of sea wave and vibration energy. When sea wave passes through the jellyfish, the wave causes the tentacles to vibrate. The tentacles is made of piezoelectric polymer which can convert the strain energy into electrical energy. This paper discusses about the piezoelectric jellyfish's tentacles being disturbed by wave in the sea. We employed the commercial CFD software CFD-ACE+ 2006 to simulate this phenomenon. The parameters including its tentacle length (L) and wave propagating function (Y) are studied which affect the piezoelectric jellyfish capacity to generate power.

  17. Wave and tide powered generation apparatus

    SciTech Connect

    Suggs, L. F.

    1985-09-03

    A wave and tide powered generation apparatus includes a frame which is fixed relative to the varying level of the body of water, and includes a float operably associated with the frame for movement in response to the varying level of the body of water. A rotatable drum is attached to the float and has a drive line with a middle portion wrapped around the rotatable drum. Upper and lower ends of the drive line are attached to upper and lower portions of the frame. Movement of the float upward or downward relative to the frame causes the rotatable drum to be rotated due to its engagement with the drive line. A power transfer apparatus transmits the rotary motion of the drum to a generator.

  18. Power generation with synthetic liquid fuels

    SciTech Connect

    Lebowitz, H.E.

    1984-06-01

    The authors report combustion tests in full-scale utility power generation equipment using Exxon Donor Solvent coal liquids and H-Coal liquids. Details of the tests are given and results are presented. It was shown that the coal liquids could be used as turbine fuels with 1800 F or higher firing temperatures. Additional industrial hygiene precautions were taken to ensure minimum crew contact with the synfuel.

  19. A microturbine for electric power generation

    Microsoft Academic Search

    Jan Peirs; Dominiek Reynaerts; Filip Verplaetsen

    2004-01-01

    A single-stage axial microturbine has been developed with a rotor diameter of 10mm. This turbine is a first step in the development of a microgenerator that produces electrical energy from fuel. The turbine is made of stainless steel using die-sinking electro-discharge machining. It has been tested to speeds up to 160,000rpm and generates a maximum mechanical power of 28W with

  20. Prediction of global solar irradiance based on time series analysis: Application to solar thermal power plants energy production planning

    Microsoft Academic Search

    Luis Martin; Ruth Marchante; Marco Cony; Luis F. Zarzalejo; Jesus Polo; Ana Navarro

    2010-01-01

    Due to strong increase of solar power generation, the predictions of incoming solar energy are acquiring more importance. Photovoltaic and solar thermal are the main sources of electricity generation from solar energy. In the case of solar thermal energy plants with storage energy system, its management and operation need reliable predictions of solar irradiance with the same temporal resolution as

  1. Cummins Power Generation SECA Phase 1

    SciTech Connect

    Charles Vesely

    2007-08-17

    The following report documents the progress of the Cummins Power Generation (CPG) SECA Phase 1 SOFC development and final testing under the U.S. Department of Energy Solid State Energy Conversion Alliance (SECA) contract DE-FC26-01NT41244. This report overviews and summarizes CPG and partner research development leading to successful demonstration of the SECA Phase 1 objectives and significant progress towards SOFC commercialization. Significant Phase 1 Milestones: (1) Demonstrated: (a) Operation meeting Phase 1 requirements on commercial natural gas. (b) LPG and Natural Gas CPOX fuel reformers. (c) SOFC systems on dry CPOX reformate. (c) Steam reformed Natural Gas operation. (d) Successful start-up and shut-down of SOFC system without inert gas purge. (e) Utility of stack simulators as a tool for developing balance of plant systems. (2) Developed: (a) Low cost balance of plant concepts and compatible systems designs. (b) Identified low cost, high volume components for balance of plant systems. (c) Demonstrated high efficiency SOFC output power conditioning. (d) Demonstrated SOFC control strategies and tuning methods. The Phase 1 performance test was carried out at the Cummins Power Generation facility in Minneapolis, Minnesota starting on October 2, 2006. Performance testing was successfully completed on January 4, 2007 including the necessary steady-state, transient, efficiency, and peak power operation tests.

  2. Thermal decomposition of furan generates propargyl radicals.

    PubMed

    Vasiliou, AnGayle; Nimlos, Mark R; Daily, John W; Ellison, G Barney

    2009-07-30

    The thermal decomposition of furan has been studied by a 1 mm x 2 cm tubular silicon carbide reactor, C(4)H(4)O + Delta --> products. Unlike previous studies, these experiments are able to identify the initial furan decomposition products. Furan is entrained in either He or Ar carrier gas and is passed through a heated (1600 K) SiC tubular reactor. Furan decomposes during transit through the tubular reactor (approximately 65 micros) and exits to a vacuum chamber. Within one nozzle diameter of leaving the nozzle, the gases cool to less than 50 K, and all reactions cease. The resultant molecular beam is interrogated by photoionization mass spectroscopy as well as infrared spectroscopy. Earlier G2(MP2) electronic structure calculations predicted that furan will thermally decompose to acetylene, ketene, carbon monoxide, and propyne at lower temperatures. At higher temperatures, these calculations forecast that propargyl radical could result. We observe all of these species (see Scheme 1). As the pressure in the tubular reactor is raised, the photoionization mass spectra show clear evidence for the formation of aromatic hydrocarbons. PMID:19719311

  3. BATTERY STORAGE CONTROL FOR STEADYING RENEWABLE POWER GENERATION

    E-print Network

    BATTERY STORAGE CONTROL FOR STEADYING RENEWABLE POWER GENERATION By Shengyuan (Mike) Chen, Emilie-626-7370 URL: http://www.ima.umn.edu #12;Battery Storage Control for Steadying Renewable Power Generation by storing excess power to a battery during excess generation, and then releasing the energy when power

  4. Security constrained dynamic dispatch of real power for thermal groups

    SciTech Connect

    Innorta, M.; Marannino, P.; Granelli, G.P.; Montagna, M.; Silverstri, A.

    1988-05-01

    This paper presents a dynamic approach to the real power dispatch of thermal units suitable for time periods characterized by high rates of load variation. In these cases dynamic dispatch places its look-ahead capability at the disposal of the system operators, enabling them to predict how the present loading (MW) and its gradient (MW/min) can influence the response rate ability of the units at a future time. In the paper a discrete formulation of the dispatch problem is adopted, with step variations of the loads. Dynamic constraints on the rate of change of the MW output of thermal units are added to the ordinary constraints of the static approach. Besides, costs associated with the act of more or less quickly changing the thermal generation are included in the model. In the solution of the problem a suitably modified version of the Han-Powell algorithm is involved in a ''compact reduced model'' formulation. Furthermore, a sparseness technique, used in the construction and in the updating of the hessian matrix of the Lagrangian function, allows us to solve large scale problems arising from a minute subdivision of the dispatch interval, also in large electrical systems.

  5. Thermoacoustic power effect on the refrigeration performance of thermal separators

    NASA Astrophysics Data System (ADS)

    Liang, S. B.; Li, X. L.; Ma, H. B.

    2003-09-01

    An experimental investigation on the refrigeration processes occurring in a receiving tube of a thermal separator was conducted in order to determine the primary factors affecting the refrigeration performance of this new type of refrigerator. In the current investigation, the gas in the system is divided into the oscillating gas and driving gas. While the compression/expansion of the oscillating gas caused by the driving gas determines the refrigeration process occurring in the receiving tube of the thermal separator, the temperature gradient on the receiving tube significantly affects the acoustic power generation and refrigeration performance. Experimental results demonstrate that when the tube-wall temperature difference near the open end of the receiving tube increases, the refrigeration coefficient increases. Using the information presented in the paper, a new cryogenic refrigeration system was developed, and the experimental data shows that the temperature of the cryogenic air flow in the system could reach -130 °C within 50 min. It suggests that the thermal separator investigated in the paper can be employed in the field of cryogenic engineering.

  6. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...the basin for the generation of electric power...pumped storage, and thermoelectric generating stations...additional hydroelectric generation, and considerable...pumped storage and thermoelectric generation. The direct...

  7. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...the basin for the generation of electric power...pumped storage, and thermoelectric generating stations...additional hydroelectric generation, and considerable...pumped storage and thermoelectric generation. The direct...

  8. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...the basin for the generation of electric power...pumped storage, and thermoelectric generating stations...additional hydroelectric generation, and considerable...pumped storage and thermoelectric generation. The direct...

  9. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...the basin for the generation of electric power...pumped storage, and thermoelectric generating stations...additional hydroelectric generation, and considerable...pumped storage and thermoelectric generation. The direct...

  10. 18 CFR 801.12 - Electric power generation.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...the basin for the generation of electric power...pumped storage, and thermoelectric generating stations...additional hydroelectric generation, and considerable...pumped storage and thermoelectric generation. The direct...

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

    PubMed

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

    2011-07-01

    The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m(-2)) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity. PMID:21532584

  12. Design, Fabrication, and Characterization of CMOS MEMS-Based Thermoelectric Power Generators

    Microsoft Academic Search

    Jin Xie; Chengkuo Lee; Hanhua Feng

    2010-01-01

    This paper presents the design, modeling, fabrication, and characterization of CMOS microelectromechanical-systems-based thermoelectric power generators (TPGs) to convert waste heat into a few microwatts of electrical power. Phosphorus and boron heavily doped polysilicon thin films are patterned and electrically connected to consist thermopiles in the TPGs. To optimize heat flux, the thermal legs are embedded between the top and bottom

  13. Microchannel cooling of traveling-wave-tube circuit for ultrawideband high-power submillimeter-wave generation

    Microsoft Academic Search

    Yanbao Ma; Avijit Bhunia; Mark Field; Chung-Lung Chen

    2010-01-01

    High heat dissipation is generated in Traveling-wave-tube circuit for ultrawideband high-power submillimeter-wave generation due to e-beam power loss during transport. Active cooling is required to ensure the device can physically handle the high heat flux without damage. An efficient thermal management solution is provided for cooling the high-power vacuum device based on microchannel technology. A thermal conduction model is developed

  14. Generation of underwater sound by a moving high-power laser source

    Microsoft Academic Search

    Y. H. Berthelot

    1985-01-01

    The generation of underwater sound by high-power laser pulse is analyzed both theoretically and experimentally. The mechanism of sound generation is the thermal expansion of the water caused by heat imparted by the laser. The basic physical properties of such a laser-induced thermoacoustic source are investigated with a time domain approach which is valid in the nearfield of the source.

  15. Generating thermal stable variants of protein domains through phage display.

    PubMed

    Pershad, Kritika; Kay, Brian K

    2013-03-15

    Often in protein design research, one desires to generate thermally stable variants of a protein or domain. One route to identifying mutations that yield domains that remain folded and active at a higher temperature is through the use of directed evolution. A library of protein domain variants can be generated by mutagenic PCR, expressed on the surface of bacteriophage M13, and subjected to heat, such that the unfolded forms of the domain, showing reduced or no binding activity, are lost during subsequent affinity selection, whereas variants that still retain binding to their target are selected and enriched with each subsequent round of affinity selection. This approach takes advantage of the fact that bacteriophage M13 particles are heat stable and resistant to many proteases and protein denaturants. We present the application of this general approach to generating thermally stable variants of a eukaryotic peptide-binding domain. The benefits of producing such variants are that they typically express at high levels in Escherichia coli (30-60 mg/L shake flask) and remain soluble in solution at higher concentrations for longer periods of time than the wild-type form of the domain. The process of library generation and screening generally requires about one month of effort, and yields variants with >10 °C increase in thermal stability, as measured in a simple fluorescence-based thermal shift assay. It is anticipated that thermally stable variants will serve as excellent scaffolds for generating affinity reagents to a variety of targets of interest. PMID:23276752

  16. Thermoelectric power enhancement by way of flow impedance for fixed thermal input conditions

    NASA Astrophysics Data System (ADS)

    Amaral, Calil; Brandão, Caio; Sempels, Éric V.; Lesage, Frédéric J.

    2014-12-01

    Liquid-to-liquid thermoelectric generators are now being considered for the purpose of converting low cost heat to electricity for local energy uses. The importance in investigating their system efficiency lies in the fact that the generator's purpose is to maintain a heat source and a heat sink for its embedded thermoelectric modules. Of particular importance is the generator's ability to maintain an asymmetric thermal field across its embedded modules since this mechanism partially dictates the devices' thermal to electric conversion efficiency. Indeed, since the modules' semiconductor materials' ability to generate an electromotive force is dependent on the quality of the thermal dipole across the material, gains in thermoelectric generator energy conversion efficiency are made possible with thermal system management. In an effort to improve the system conversion efficiency of a liquid-to-liquid thermoelectric generator (TEG), the present work builds upon recent advancements in TEG inner pipe flow optimisation by investigating the thermoelectric power enhancement brought upon by flow impeding panel inserts in a thermoelectric generator's flow channels for fixed thermal input conditions and with respect to varying insert panel densities. The pumping penalty associated with the flow impedance is measured in order to present and to discuss the net thermoelectric power enhancement.

  17. Power Generator with Thermo-Differential Modules

    NASA Technical Reports Server (NTRS)

    Saiz, John R.; Nguyen, James

    2010-01-01

    A thermoelectric power generator consists of an oven box and a solar cooker/solar reflector unit. The solar reflector concentrates sunlight into heat and transfers the heat into the oven box via a heat pipe. The oven box unit is surrounded by five thermoelectric modules and is located at the bottom end of the solar reflector. When the heat is pumped into one side of the thermoelectric module and ejected from the opposite side at ambient temperatures, an electrical current is produced. Typical temperature accumulation in the solar reflector is approximately 200 C (392 F). The heat pipe then transfers heat into the oven box with a loss of about 40 percent. At the ambient temperature of about 20 C (68 F), the temperature differential is about 100 C (180 F) apart. Each thermoelectric module, generates about 6 watts of power. One oven box with five thermoelectric modules produces about 30 watts. The system provides power for unattended instruments in remote areas, such as space colonies and space vehicles, and in polar and other remote regions on Earth.

  18. Manure digester and power generating system

    SciTech Connect

    Santina, P.F.; Chatterjee, A.K.

    1988-06-14

    A manure digester and power generating system is described comprising: a mixing tank for receiving manure, and for mixing water with the manure to produce a manure slurry of desired consistency; a closed anaerobic digester tank of fixed volume; the mixing tank being separate from and spaced from the digester tank; pumping and conduit means for transferring the contents of the mixing tank to the digester tank; automatic control means, associated with the pumping means, for monitoring and controlling temperature and volume of the contents of the mixing tank before transfer to the digester tank; means for discharging effluent by-products out the outflow end of the digester tank; a gas-fueled engine and a generator coupled to the engine, for generating electrical power; heater means; means for drawing off biogas from the digester tank and for conducting it to the engine as fuel, and wherein the manure slurry is heated sufficiently, prior to introduction into the digester tank and separately from the digester tank, to prevent temperature shock of already digesting slurry in the digester tank when the slurry is introduced into the digester tank.

  19. Compressed air energy storage turbomachinery cycle with compression heat recovery, storage, steam generation and utilization during power generation

    Microsoft Academic Search

    Nakhamkin

    1988-01-01

    This patent describes a compressed Air Energy Storage (CAES) plant cycle which utilizes otherwise wasted compression heat by storing such heat in a thermal energy storage (TES) device for subsequent use for steam generation and injection into compressed air flow before entering a high pressure combustion which expands such compressed air to produce additional power. The cycle consists of the

  20. The status of biomass power generation and its solutions in our country

    Microsoft Academic Search

    Guanghui Hua; Weiguo He

    2011-01-01

    The biomass power generation, which uses the power of biomass for generation, is an important way of renewable energy power generation, including the plant biomass power generation, waste power generation, gas power generation and so on. This paper analyzes the importance of biomass power generation, describes the actuality of biomass power generation and the problems faced, and the outlets are

  1. Dynamic modeling and control strategies for a micro-CSP plant with thermal storage powered by the Organic Rankine cycle

    E-print Network

    Ireland, Melissa Kara

    2014-01-01

    Organic Rankine cycle (ORC) systems are gaining ground as a means of effectively providing sustainable energy. Coupling small-scale ORCs powered by scroll expander- generators with solar thermal collectors and storage can ...

  2. Development of an HTS hydroelectric power generator for the hirschaid power station

    NASA Astrophysics Data System (ADS)

    Fair, Ruben; Lewis, Clive; Eugene, Joseph; Ingles, Martin

    2010-06-01

    This paper describes the development and manufacture of a 1.7MW, 5.25kV, 28pole, 214rpm hydroelectric power generator consisting of superconducting HTS field coils and a conventional stator. The generator is to be installed at a hydro power station in Hirschaid, Germany and is intended to be a technology demonstrator for the practical application of superconducting technology for sustainable and renewable power generation. The generator is intended to replace and uprate an existing conventional generator and will be connected directly to the German grid. The HTS field winding uses Bi-2223 tape conductor cooled to about 30K using high pressure helium gas which is transferred from static cryocoolers to the rotor via a bespoke rotating coupling. The coils are insulated with multi-layer insulation and positioned over laminated iron rotor poles which are at room temperature. The rotor is enclosed within a vacuum chamber and the complete assembly rotates at 214rpm. The challenges have been significant but have allowed Converteam to develop key technology building blocks which can be applied to future HTS related projects. The design challenges, electromagnetic, mechanical and thermal tests and results are presented and discussed together with applied solutions.

  3. Power Modeling and Thermal Management Techniques for Manycores

    E-print Network

    Simunic, Tajana

    Power Modeling and Thermal Management Techniques for Manycores Rajib Nath Computer Science number of cores in manycore archi- tectures, along with technology scaling, results in high power in such processors, we need an accurate online estimate of the power consumption. In this paper, we present the first

  4. Review Article Solar-Thermal Powered Desalination: Its Significant

    E-print Network

    Reif, John H.

    1 Review Article Solar-Thermal Powered Desalination: Its Significant Challenges and Potential John@kau.edu.sa Abstract Solar-desalination systems are desalination systems that are powered by solar energy-recovery. Existing demonstrations of solar-powered desalination systems have generally been indirect solar

  5. High-power Broadband Organic THz Generator

    PubMed Central

    Jeong, Jae-Hyeok; Kang, Bong-Joo; Kim, Ji-Soo; Jazbinsek, Mojca; Lee, Seung-Heon; Lee, Seung-Chul; Baek, In-Hyung; Yun, Hoseop; Kim, Jongtaek; Lee, Yoon Sup; Lee, Jae-Hyeok; Kim, Jae-Ho; Rotermund, Fabian; Kwon, O-Pil

    2013-01-01

    The high-power broadband terahertz (THz) generator is an essential tool for a wide range of THz applications. Here, we present a novel highly efficient electro-optic quinolinium single crystal for THz wave generation. For obtaining intense and broadband THz waves by optical-to-THz frequency conversion, a quinolinium crystal was developed to fulfill all the requirements, which are in general extremely difficult to maintain simultaneously in a single medium, such as a large macroscopic electro-optic response and excellent crystal characteristics including a large crystal size with desired facets, good environmental stability, high optical quality, wide transparency range, and controllable crystal thickness. Compared to the benchmark inorganic and organic crystals, the new quinolinium crystal possesses excellent crystal properties and THz generation characteristics with broader THz spectral coverage and higher THz conversion efficiency at the technologically important pump wavelength of 800?nm. Therefore, the quinolinium crystal offers great potential for efficient and gap-free broadband THz wave generation. PMID:24220234

  6. Thermoelectric Analysis for Helical Power Generation Systems

    NASA Astrophysics Data System (ADS)

    Meng, Xiangning; Fujisaka, Takeyuki; Suzuki, Ryosuke O.

    2014-06-01

    The performance of a three-dimensional helical thermoelectric generation (TEG) system is examined by exposing it to a temperature difference with hot and cold sources. The helical paths for the two thermal fluids give the TEG device the potential to efficiently convert thermal energy. The characteristic performance of the helical system is numerically analyzed by using the finite-volume method in a compact system. The helical system is compared with a straight system in which all the thermoelectric (TE) elements present equivalent geometry. The difference in the TE performance between the two systems is not significant when the TE surfaces are maintained at constant temperatures. Both the electromotive force and the current in the TEG system increase linearly with the temperature difference ? T applied at the two module surfaces. The current preferentially flows through a main path determined by the geometry of the TE element. The merits of the helical design are its compactness, space saving, and smooth fluid flow due to gravity, compared with the straight system.

  7. A Thermal and Electrical Analysis of Power Semiconductor Devices

    NASA Technical Reports Server (NTRS)

    Vafai, Kambiz

    1997-01-01

    The state-of-art power semiconductor devices require a thorough understanding of the thermal behavior for these devices. Traditional thermal analysis have (1) failed to account for the thermo-electrical interaction which is significant for power semiconductor devices operating at high temperature, and (2) failed to account for the thermal interactions among all the levels involved in, from the entire device to the gate micro-structure. Furthermore there is a lack of quantitative studies of the thermal breakdown phenomenon which is one of the major failure mechanisms for power electronics. This research work is directed towards addressing. Using a coupled thermal and electrical simulation, in which the drift-diffusion equations for the semiconductor and the energy equation for temperature are solved simultaneously, the thermo-electrical interactions at the micron scale of various junction structures are thoroughly investigated. The optimization of gate structure designs and doping designs is then addressed. An iterative numerical procedure which incorporates the thermal analysis at the device, chip and junction levels of the power device is proposed for the first time and utilized in a BJT power semiconductor device. In this procedure, interactions of different levels are fully considered. The thermal stability issue is studied both analytically and numerically in this research work in order to understand the mechanism for thermal breakdown.

  8. Technology of a freon and steam reciprocating engine for low temperature solar thermal powered water pump

    Microsoft Academic Search

    1983-01-01

    This paper comprises a comparative study between a Freon-11 and steam reciprocating engine for low temperature solar thermal powered water pump. Theoretical aspects like thermal efficiency, cycle work and feed pump work have been compared using Freon-11 and steam as working fluid assuming a generator temperature of 80°C at two different condenser temperatures (30° and 40°C). The ratio of the

  9. Power Generation and Power Use Decisions in an Industrial Process 

    E-print Network

    Gilbert, J. S.; Niess, R. C.

    1987-01-01

    is that boiling point eleva tion should not be presumed. Backing off a little on the final concentration often indicates that a pre-evaporation step can produce dramatic reduc tions in steam demand. STEAM OR GAS TURBINE If power is to be generated, should a... is the temperature at which the evaporator is running minus the boiling point elevationI or the temperature of the vapors off the evaporator to the heat pump. pumping heat will be economic only where the phase changes are within a few degrees of each other...

  10. Exploiting metastability and thermal noise to build a reconfigurable hardware random number generator

    NASA Astrophysics Data System (ADS)

    Lim, Daihyun; Ranasinghe, Damith C.; Devadas, Srinivas; Jamali, Behnam; Abbott, Derek; Cole, Peter H.

    2005-05-01

    While pseudo random number generators based on computational complexity are widely used for most of cryptographic applications and probabilistic simulations, the generation of true random numbers based on physical randomness is required to guarantee the advanced security of cryptographic systems. In this paper we present a method to exploit manufacturing variations, metastablity, and thermal noise in integrated circuits to generate random numbers. This metastability based physical random number generator provides a compact and low-power solution which can be fabricated using standard IC manufacturing processes. Test-chips were fabricated in TSMC 0.18um process and experimental results show that the generated random bits pass standard randomness tests successfully. The operation of the proposed scheme is robust against environmental changes since it can be re-calibrated to new environmental conditions such as temperature and power supply voltage.

  11. Generator solutions for stand alone pico-electric power plants

    Microsoft Academic Search

    D. Fodorean; L. Szabo; A. Miraoui

    2009-01-01

    This paper presents several solutions for stand alone pico-electric power plants, which are used for electric energy production from water power. Up to now, the induction and permanent magnet synchronous generators were studied and presented as best variants for small power generation. Another topology is proposed here: a hybrid excited synchronous generator, based on two different types of excitation field:

  12. Binary vapor cycle method of electrical power generation

    Microsoft Academic Search

    Humiston

    1982-01-01

    A binary vapor cycle method of electrical power generation is disclosed wherein two refrigerant fluids can be used to operate an apparatus for the generation of mechanical power as well as electrical power generation. This method, which is essentially a dual heat pump system, offers an approach to utilizing the advantages of two different refrigerants within a single apparatus. This

  13. Characteristics of wind turbine generators for wind power plants

    Microsoft Academic Search

    E. H. Camm; M. R. Behnke; O. Bolado; M. Bollen; M. Bradt; C. Brooks; W. Dilling; M. Edds; W. J. Hejdak; D. Houseman; S. Klein; F. Li; J. Li; P. Maibach; T. Nicolai; J. Patino; S. V. Pasupulati; N. Samaan; S. Saylors; T. Siebert; T. Smith; M. Starke; R. Walling

    2009-01-01

    This paper presents a summary of the most important characteristics of wind turbine generators applied in modern wind power plants. Various wind turbine generator designs, based on classification by machine type and speed control capabilities, are discussed along with their operational characteristics, voltage, reactive power, or power factor control capabilities, voltage ride-through characteristics, behavior during short circuits, and reactive power

  14. Prospectives for China's solar thermal power technology development

    Microsoft Academic Search

    Zhifeng Wang

    2010-01-01

    China's total installed electrical power capacity reached 700GW by the end of 2007 and is predicted to surpass 900GW in 2010. The rapid increase in energy demand and increasing global warming have both pushed China to change its current electrical power structure where coal power accounts for nearly 75% of the total electric power generation. China has already become the

  15. Solar thermal powered desalination: membrane versus distillation technologies

    Microsoft Academic Search

    G. Burgess; K. Lovegrove

    Multiple Effect Distillation (MED) is generally considered to be the desalination technology most suited to integration with concentrating solar thermal collectors on a medium to large scale. However the cost and energy requirement of Reverse Osmosis (RO) have fallen significantly in recent years, so that solar thermal powered RO deserves consideration. We compare commercial desalination processes on the basis of

  16. Proceedings of the Fifth Parabolic Dish Solar Thermal Power Program

    Microsoft Academic Search

    J. W. Lucas

    1984-01-01

    The proceedings of the Fifth Parabolic Dish Solar Thermal Power Program Annual Review are presented. The results of activities within the Parabolic Dish Technology and Module\\/Systems Development element of the Department of Energy's Solar Thermal Energy Systems Program were emphasized. Among the topics discussed were: overall Project and Program aspects, Stirling and Brayton module development, concentrator and engine\\/receiver development along

  17. Performance evaluation of solar thermal electric generation systems

    Microsoft Academic Search

    S. D Odeh; M Behnia; G. L Morrison

    2003-01-01

    A unified model of a solar electric generation system (SEGS) is developed using a thermo–hydrodynamic model of a direct steam collector combined with a model of a traditional steam power house. The model is used to study the performance of different collector field and power house arrangements under Australian conditions. To find the effect of collector inclination on the SEGS

  18. Cool Chips: Opportunities and Implications for Power and Thermal Management

    Microsoft Academic Search

    Sheng-Chih Lin; Kaustav Banerjee

    2008-01-01

    Alongside innovative device, circuit, and microarchitecture level techniques to alleviate power and thermal problems in nanoscale CMOS-based integrated circuits (ICs), chip cooling could be an effective knob for power and thermal management. This paper analyzes IC cooling while focusing on the practical temperature range of operation. Comprehensive analyses of chip cooling for various nanometer scale bulk-CMOS and silicon-on-insulator (SOI) technologies

  19. Treatment and reuse of industrial effluents: case study of a thermal power plant

    Microsoft Academic Search

    Mousa S. Mohsen

    2004-01-01

    This paper presents a study of the potential of industrial wastewater reuse in Jordan's Al Hussein thermal power station. A comprehensive review of the processes involved, industrial waste generation and water requirements was carried out, and areas of potential improvment were identified. They include a water treatment system, blow-down system, flue gas desulfurization and finding alternative process water sources such

  20. A Comparison Study of Sensible and Latent Thermal Energy Storage Systems for Concentrating Solar Power Applications

    Microsoft Academic Search

    Shimin Wang; Amir Faghri; Theodore L. Bergman

    2012-01-01

    Thermal energy storage (TES) provides a key opportunity to reduce the cost of concentrating solar power generation. In this article transient heat transfer performance and operational characteristics of sensible TES systems (made of liquid solar salt) and latent TES systems (made of sodium nitrate undergoing liquid-solid phase change), all enclosed in vertical annuli, are numerically simulated. The results show that

  1. Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m

    ScienceCinema

    None

    2013-05-28

    Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m is a linear electron accelerator-based technology for producing medical imaging radioisotopes from a separation process that heats, vaporizes and condenses the desired radioisotope. You can learn more about INL's education programs at http://www.facebook.com/idahonationallaboratory.

  2. Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m

    SciTech Connect

    None

    2010-01-01

    Accelerator Generation and Thermal Separation (AGATS) of Technetium-99m is a linear electron accelerator-based technology for producing medical imaging radioisotopes from a separation process that heats, vaporizes and condenses the desired radioisotope. You can learn more about INL's education programs at http://www.facebook.com/idahonationallaboratory.

  3. Irreversibilities and efficiency at maximum power of heat engines: illustrative case of a thermoelectric generator

    E-print Network

    Apertet, Y; Goupil, C; Lecoeur, Ph

    2011-01-01

    Thermoelectric generators are particularly suitable to investigate the irreversible processes which govern the coupled transport of matter and heat in solid-state systems. We study the efficiency at maximum power in the strong coupling regime, where the thermal flux is proportionnal to the electrical current inside the generator. We demonstrate that depending on the source of irreversibility we obtain either the Curzon-Ahlborn efficiency for external dissipation or a universal efficiency at maximum power for internal dissipation. A continuous change between these two extremes is evidenced. Effects of dissymetry of thermal contact conductance are also investigated.

  4. Thermal Energy Corporation Combined Heat and Power Project

    SciTech Connect

    E. Bruce Turner; Tim Brown; Ed Mardiat

    2011-12-31

    To meet the planned heating and cooling load growth at the Texas Medical Center (TMC), Thermal Energy Corporation (TECO) implemented Phase 1 of a Master Plan to install an additional 32,000 tons of chilled water capacity, a 75,000 ton-hour (8.8 million gallon) Thermal Energy Storage (TES) tank, and a 48 MW Combined Heat and Power (CHP) system. The Department of Energy selected TMC for a $10 million grant award as part of the Financial Assistance Funding Opportunity Announcement, U.S. Department of Energy National Energy Technology, Recovery Act: Deployment of Combined Heat and Power (CHP) Systems, District Energy Systems, Waste Energy Recovery Systems, and Efficiency Industrial Equipment Funding Opportunity Number: DE-FOA-0000044 to support the installation of a new 48 MW CHP system at the TMC located just outside downtown Houston. As the largest medical center in the world, TMC is home to many of the nationâ??s best hospitals, physicians, researchers, educational institutions, and health care providers. TMC provides care to approximately six million patients each year, and medical instruction to over 71,000 students. A medical center the size of TMC has enormous electricity and thermal energy demands to help it carry out its mission. Reliable, high-quality steam and chilled water are of utmost importance to the operations of its many facilities. For example, advanced medical equipment, laboratories, laundry facilities, space heating and cooling all rely on the generation of heat and power. As result of this project TECO provides this mission critical heating and cooling to TMC utilizing a system that is both energy-efficient and reliable since it provides the capability to run on power independent of the already strained regional electric grid. This allows the medical center to focus on its primary mission â?? providing top quality medical care and instruction â?? without worrying about excessive energy costs or the loss of heating and cooling due to the risk of power outages. TECOâ??s operation is the largest Chilled Water District Energy System in the United States. The company used DOEâ??s funding to help install a new high efficiency CHP system consisting of a Combustion Turbine and a Heat Recovery Steam Generator. This CHP installation was just part of a larger project undertaken by TECO to ensure that it can continue to meet TMCâ??s growing needs. The complete efficiency overhaul that TECO undertook supported more than 1,000 direct and indirect jobs in manufacturing, engineering, and construction, with approximately 400 of those being jobs directly associated with construction of the combined heat and power plant. This showcase industrial scale CHP project, serving a critical component of the nationâ??s healthcare infrastructure, directly and immediately supported the energy efficiency and job creation goals established by ARRA and DOE. It also provided an unsurpassed model of a district energy CHP application that can be replicated within other energy intensive applications in the industrial, institutional and commercial sectors.

  5. Transient thermal analysis of a space reactor power system

    E-print Network

    Gaeta, Michael J.

    1988-01-01

    The overall thermal performance of a space reactor posver system is mod- eled. The thermal analysis is loosely coupled to a momentum analysis. This loose coupling simplifies solution and decreases runtime of the code. The reac- tor model includes... an expression for energy generation due to fission as well as s term that accounts for energy generation {'r om decay heat. The thermoelectric heat exchanger model accounts for energy conversion to useful electrical output v hich is handled by a posver...

  6. Microwave power heterojunction bipolar transistors fabricated with thermal shunt bathtub

    SciTech Connect

    Bozada, C.A.; Barlage, D.W.; Barrette, J.P. [and others

    1995-12-31

    Heterojunction bipolar transistor devices and circuits were fabricated using thermal shunt and bathtub thermal management techniques. Broadband cascode MMICs exhibited 10 - 14 dB gain at an output power of 2.5 - 3.0 Watts across 7 - 11 GHz. A 200 {mu}m{sup 2} common-emitter unit cell achieved 7 - 8 dB linear power gain and 40% power-added efficiency at a noise power ratio (NPR) of 18 dBc at 12 GHz. Under single tone measurements at 12 GHz, the unit cell achieved 52% power-added efficiency, with 9.5 dB linear gain, 8 dB power gain and 240 mW output power at 5 V bias.

  7. Analysis of Wind Power Generation of Texas 

    E-print Network

    Liu, Z.; Haberl, J.; Subbarao, K.; Baltazar, J. C.

    2007-01-01

    1 ? Energy Systems Laboratory, Texas A&M University Page 1 ANALYSIS OF WIND POWER GENERATION OF TEXAS April 2007 Zi ?Betty? Liu, Ph.D., Jeff Haberl, Ph.D., P.E., Kris Subbarao, Ph.D., P.E., Juan-Carlos Baltazar, Ph.D. Energy Systems Laboratory... Jun-03 Month Ca pa cit y F ac to r 0 4 8 12 16 20 24 Av er ag e D ail y W in d Sp ee d Pe r M on th (m ph ) M easured CF NOA A-FST Daily M odel CF ANN On-site Daily M odel CF A NN On-site Wind Speed NOA A Wind Speed OSP Indian Mesa Wind Farm (Jul...

  8. Nanostructured thermal batteries with high power density

    NASA Astrophysics Data System (ADS)

    Au, Ming

    Nanostructured FeS 2 has been synthesized and used as the cathode material in LiSi/FeS 2 thermal batteries. With the same weight, the nanostructured cathode pellets are 23% thinner than conventional counterparts resulting in 31% increase of pellet density. Therefore, the volume of batteries can be reduced significantly. With the nanostructure, the electrode materials of the thermal batteries react more rapidly and completely during discharge resulting with a remarkable increase of energy output. The discharge tests show that the energy density of the nanostructured thermal batteries is two times higher (109 J/g) than the conventional counterpart (58 J/g). The nanostructured pellets are more robust mechanically than the conventional counterparts that could increase productivity and lower manufacturing cost.

  9. Thermal Properties of Power Terminals in High Power IGBT Modules

    Microsoft Academic Search

    A. Cosaert; M. Beulque; M. Wölz; O. Schilling; H. Sandmann; R. Spanke; K. Appelhoff

    Power dissipation in the leads of IGBT modules has to be taken into account for modern inverter design. This is due to the fact that the total losses of the semiconductors are continuously decreasing while current density increases. This work analyzes the heat budget of the power terminals and the inverter interconnections. Different concepts are discussed for power terminals in

  10. Comparison of electrochemical and thermal storage for hybrid parabolic dish solar power plants

    Microsoft Academic Search

    H. L. Steele; L. Wen

    1981-01-01

    The economic and operating performance of a parabolic point focus array of solar electricity generators combined with either battery or thermal energy storage are examined. Noting that low-cost, mass-producible power generating units are under development for the point focus of distributed dishes, that Zn-Cl battery tests will begin in 1981 and a 100 kWh Na-S battery in 1983, the state

  11. Design of Commercial Solar Updraft Tower Systems—Utilization of Solar Induced Convective Flows for Power Generation

    Microsoft Academic Search

    Jo?rg Schlaich; Rudolf Bergermann; Wolfgang Schiel; Gerhard Weinrebe

    2005-01-01

    A solar updraft tower power plant - sometimes also called 'solar chimney' or just 'solar tower' - is a solar thermal power plant utilizing a combination of solar air collector and central updraft tube to generate a solar induced convective flow which drives pressure staged turbines to generate electricity. The paper presents theory, practical experience, and economy of solar updraft

  12. Power generation from nuclear reactors in aerospace applications

    SciTech Connect

    English, R.E.

    1982-01-01

    Power generation in nuclear powerplants in space is addressed. In particular, the states of technology of the principal competitive concepts for power generation are assessed. The possible impact of power conditioning on power generation is also discussed. For aircraft nuclear propulsion, the suitability of various technologies is cursorily assessed for flight in the Earth's atmosphere. A program path is suggested to ease the conditions of first use of aircraft nuclear propulsion.

  13. Power Generation from Nuclear Reactors in Aerospace Applications

    NASA Technical Reports Server (NTRS)

    English, Robert E.

    1982-01-01

    Power generation in nuclear powerplants in space is addressed. In particular, the states of technology of the principal competitive concepts for power generation are assessed. The possible impact of power conditioning on power generation is also discussed. For aircraft nuclear propulsion, the suitability of various technologies is cursorily assessed for flight in the Earth's atmosphere; a program path is suggested to ease the conditions of first use of aircraft nuclear propulsion.

  14. Reliability problems in power-generation systems

    SciTech Connect

    Bryson, M.C. (ed.)

    1980-01-01

    Some widely publicized incidents have called attention to the problems of reliability, safety, and dependability of power-generation systems, increasing public pressure for additional safety guarantees in power systems. The tendency has been to demand guarantees to zero-risk, an attitude which both augments and is augmented by the slow-growth ethic that has become familiar through the 1970s. It is the suggestion of this discussion paper that, regardless of the merits of different political positions on these issues, it is essential to have a more-precise understanding of the factors that are involved: specifically, that mathematical/statistical tools be developed and made available to potential users in order to quantify the magnitude of the risks inherent in using or failing to use competing technologies. The following are discussed: estimation of very-low-failure probabilities; complex-system reliability methodologies; dependence in failure modes; use of observational-study data; communication of reliability data to nontechnical individuals; semi-parametric procedures; estimating the reliability of man-machine systems; degraded-operation failure modes; pooling data; and accelerated data collection.

  15. Cache decay: exploiting generational behavior to reduce cache leakage power

    Microsoft Academic Search

    Stefanos Kaxiras; Zhigang Hu; Margaret Martonosi

    2001-01-01

    Power dissipation is increasingly important in CPUs rang- ing from those intended for mobile use, all the way up to high- performance processors for high-end servers. While the bulk of the power dissipated is dynamic switching power, leakage power is also beginning to be a concern. Chipmakers expect that in future chip generations, leakage's proportion of total chip power will

  16. Air Force Perspective on Present and Future Space Power Generation

    Microsoft Academic Search

    John M. Merrill; Paul Hausgen; Donna Senft; Jennifer Granata

    2006-01-01

    Photovoltaics continue to be the primary source for electric power for space missions. The need for ever higher power, specific power, areal power density, and radiation resistance continues to push development of novel solar cell technologies. To meet present and future space power requirements, conventional crystalline multijunction solar cells, next generation thin-film solar cells, and novel technologies are being pursued.

  17. ERDA's central receiver solar thermal power system studies

    NASA Technical Reports Server (NTRS)

    Lippy, L. J.; Heaton, T. R.

    1977-01-01

    The utilization of solar energy for electrical power production was studied. Efforts underway on the central receiver solar thermal power system are presented. Preliminary designs are included of pilot plant utilizing large numbers of heliostats in a collector field. Safety hazards are also discussed, as well as the most beneficial location of such a plant within the United States.

  18. Thermal management of power electronics using thermoelectric coolers

    Microsoft Academic Search

    J. W. Vandersande; J.-P. Fleurial

    1996-01-01

    Many high power electronic devices, such as power amplifies and multiprocessors, operate at high temperatures close to or at the edge of their reliability, which could severely impact performance and operating lifetime. These devices thus need cooling to improve performance and reliability. Conventional thermal management techniques, most of which are discussed, are not well suited to the specific problem of

  19. Photoacoustic transients produced by laser generated, ultrahigh thermal gradients

    NASA Astrophysics Data System (ADS)

    Wu, Binbin; Frez, Clifford; Diebold, Gerald J.

    2013-09-01

    Irradiation of an absorbing surface in contact with a transparent fluid by a pulsed laser can result in generation of enormous thermal gradients. Here it is shown that the effect of such thermal gradients on photoacoustic waves is the production of fast transients that accompany the leading edge of the wave. Calculations show that the transients can be accounted for by an additional source term in the wave equation for pressure. Experiments are reported showing the predicted transients on waves from absorbing layers submerged in transparent fluids irradiated with 10 ns laser pulses.

  20. Self-powered signal processing using vibration-based power generation

    Microsoft Academic Search

    Rajeevan Amirtharajah; Anantha P. Chandrakasan

    1998-01-01

    Low power design trends raise the possibility of using ambient energy to power future digital systems. A chip has been designed and tested to demonstrate the feasibility of operating a digital system from power generated by vibrations in its environment. A moving coil electromagnetic transducer was used as a power generator. Calculations show that power on the order of 400

  1. Energy management in solar thermal power plants with double thermal storage system and subdivided solar field

    Microsoft Academic Search

    Antonio Rovira; Manuel Valdes; José María Martínez-Val

    2011-01-01

    In the paper, two systems for solar thermal power plants (STPPs) are devised for improving the overall performance of the plant. Each one attempts to reduce losses coming from two respective sources. The systems are simulated and compared to a reference STPP.They consists on: (a) a double thermal energy storage (DTS) with different functionalities for each storage and (b) the

  2. Worker health and safety in solar thermal power systems. III. Thermal energy storage subsystems

    Microsoft Academic Search

    A. Z. Ullman; B. B. Sokolow; J. Daniels; P. Hurt

    1979-01-01

    The effects of the use of thermal energy storage (TES) subsystems in solar thermal power systems (STPS) on operating failures and on worker health and safety are examined. Relevant near- and medium-term designs for TES subsystems are reviewed. Generic failure events are considered by an event tree methodology. Three generic categories of initiating events are identified which can lead to

  3. Worker health and safety in solar thermal power systems. III. Thermal energy storage subsystems

    Microsoft Academic Search

    A. Z. Ullman; B. B. Sokolow; J. Daniels; P. Hurt

    1979-01-01

    The effects of the use of thermal energy storage (TES) subsystems in solar thermal power systems (STPS) on operating failures and on worker health and safety are examined. Revelant near- and medium-term designs for TES subsystems are reviewed. Generic failure events are considered by an event tree methodology. Three generic categories of initiating events are identified which can lead to

  4. Improvement of financial efficiency and cost effectiveness in energy sector: A case study from Indian thermal power plant

    Microsoft Academic Search

    S. Ghosh; S. C. Basu; P. P. Sengupta

    2010-01-01

    Electricity is generated based on potential resources like coal, crude oil, water, wind, solar and nuclear energy. India depends largely on thermal power using coal as raw material despite the reality that indigenous stock of this raw material is depleting fast. At the same time coal based thermal stations are losing out financial viability gradually in terms of deteoriating efficiency,

  5. Power MOSFET Thermal Instability Operation Characterization Support

    NASA Technical Reports Server (NTRS)

    Shue, John L.; Leidecker, Henning

    2010-01-01

    Metal-oxide semiconductor field-effect transistors (MOSFETs) are used extensively in flight hardware and ground support equipment. In the quest for faster switching times and lower "on resistance," the MOSFETs designed from 1998 to the present have achieved most of their intended goals. In the quest for lower on resistance and higher switching speeds, the designs now being produced allow the charge-carrier dominated region (once small and outside of the area of concern) to become important and inside the safe operating area (SOA). The charge-carrier dominated region allows more current to flow as the temperature increases. The higher temperatures produce more current resulting in the beginning of thermal runaway. Thermal runaway is a problem affecting a wide range of modern MOSFETs from more than one manufacturer. This report contains information on MOSFET failures, their causes and test results and information dissemination.

  6. Thermal management of next-generation contact-cooled synchrotron x-ray mirrors

    SciTech Connect

    Khounsary, A.

    1999-10-29

    In the past decade, several third-generation synchrotrons x-ray sources have been constructed and commissioned around the world. Many of the major problems in the development and design of the optical components capable of handling the extremely high heat loads of the generated x-ray beams have been resolved. It is expected, however, that in the next few years even more powerful x-ray beams will be produced at these facilities, for example, by increasing the particle beam current. In this paper, the design of a next generation of synchrotron x-ray mirrors is discussed. The author shows that the design of contact-cooled mirrors capable of handing x-ray beam heat fluxes in excess of 500 W/mm{sup 2} - or more than three times the present level - is well within reach, and the limiting factor is the thermal stress rather then thermally induced slope error.

  7. Assessment of integrated gasification combined cycle power generation

    Microsoft Academic Search

    D. A. Huber; R. J. Kirk; J. Pietruszkiewicz; R. S. Smith

    1983-01-01

    This paper presents the results of a comparative study of various selected technologies for coal-fired electric power generation with emphasis on the generation of power using the Integrated Gasification Combined Cycle (IGCC) Concept. All of the power plant conceptual designs were prepared as grassroots plants with a nominal output of 500 MWe, located in the east-central region of the United

  8. ''An assessment of integrated gasification combined cycle power generation''

    Microsoft Academic Search

    D. A. Hauber; R. J. Kirk; J. Pietruszkiewicz; R. S. Smith

    1983-01-01

    This paper presents the results of a comparative study of various selected technologies for coal-fired electric power generation with emphasis on the generation of power using the Integrated Gasification Combined Cycle (IGCC) Concept. This study was managed by Argonne National Laboratory for the U.S. Department of Energy, Office of Coal Utilization. All of the power plant conceptual designs were prepared

  9. Concentrated Solar Power Generation Systems: The SAIC Dish

    E-print Network

    Hemmers, Oliver

    Concentrated Solar Power Generation Systems: The SAIC Dish Center for Energy Research at UNLV #12 of concentrating solar dishes for electrical power generation. One of these solar dishes was marketed by Science the sun, resulting in a very high intensity solar beam on the target. This beam can be used to power

  10. International comparison of energy efficiency of fossil power generation

    Microsoft Academic Search

    W. H. J. Graus; M. Voogt; E. Worrell

    2007-01-01

    The purpose of this study is to compare the energy efficiency of fossil-fired power generation for Australia, China, France, Germany, India, Japan, Nordic countries (Denmark, Finland, Sweden and Norway aggregated), South Korea, United Kingdom and Ireland, and United States. Together these countries generate 65% of worldwide fossil power generation. Separate benchmark indicators are calculated for the energy efficiency of natural

  11. Analysis of waste-heat thermoelectric power generators

    Microsoft Academic Search

    Chih Wu

    1996-01-01

    A real thermoelectric power generator utilizing waste heat is proposed. The generator is treated as an external and internal irreversible heat engine. The specific power output of the generator is analyzed and compared with that of the Carnot, endoreversible and external reversible thermoelectric heat engines.

  12. 13. INTERIOR OF POWER PLANT LOOKING EASTNORTHEAST. 1925 GE GENERATOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. INTERIOR OF POWER PLANT LOOKING EAST-NORTHEAST. 1925 GE GENERATOR IN FOREGROUND, WITH C. 1910 GENERATOR COVER IN BACKGROUND. STEEL FRAME SUPPORTS HOISTING MECHANISM USED TO MOVE, REPAIR, OR REPLACE GENERATORS. - Potomac Power Plant, On West Virginia Shore of Potomac River, about 1 mile upriver from confluence with Shenandoah River, Harpers Ferry, Jefferson County, WV

  13. Mercury's thermal history and the generation of its magnetic field

    NASA Technical Reports Server (NTRS)

    Schubert, G.; Ross, M. N.; Stevenson, D. J.; Spohn, T.

    1988-01-01

    Thermal history of Mercury's interior is examined using the model of Stevenson et al. (1983), extended to include the effects of tidal heating in Mercury's solid inner core. The implications of Mercury's thermal history for the source of the planet's magnetic field are discussed. It is shown that the major results of this model are similar to the results obtained with the Stevenson et al. model, except for the addition of inner-core tidal dissipation. It is concluded that the extended model properly characterizes Mercury's internal structure and thermal history, and that the criteria for dynamo generation are not properly satisfied. Alternative explanations, including the possibility of a weak thermoelectric dynamo, are examined.

  14. Thermal Analysis and Testing of Fastrac Gas Generator Design

    NASA Technical Reports Server (NTRS)

    Nguyen, H.

    1998-01-01

    The Fastrac Engine is being developed by the Marshall Space Flight Center (MSFC) to help meet the goal of substantially reducing the cost of access to space. This engine relies on a simple gas-generator cycle, which burns a small amount of RP-1 and oxygen to provide gas to drive the turbine and then exhausts the spent fuel. The Fastrac program envisions a combination of analysis, design and hot-fire evaluation testing. This paper provides the supporting thermal analysis of the gas generator design. In order to ensure that the design objectives were met, the evaluation tests have started on a component level and a total of 15 tests of different durations were completed to date at MSFC. The correlated thermal model results will also be compared against hot-fire thermocouple data gathered.

  15. Acoustic harmonic generation due to thermal embrittlement of inconel 718

    Microsoft Academic Search

    D. J. Barnard; G. E. Dace; O. Buck

    1997-01-01

    This paper describes an attempt to characterize the deterioration of a structural material's mechanical properties by nonlinear\\u000a acoustics. In this particular case, the damage was caused by “thermal embrittlement” during which the material, here the nickel-based\\u000a alloy Inconel 718, loses a significant fraction of its fracture toughness. Harmonic generation was the experimental method\\u000a used to characterize the microstructural changes in

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

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

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

  17. Comparison of nuclear and solar power plants with turboelectric generators for application in space

    NASA Astrophysics Data System (ADS)

    Blumenberg, Jürgen; Ruppe, Harry O.

    The aim of the analysis is to determine and to compare the specific mass of nuclear and solar power plants for application in space depending on technological data as well as on data subject to the mission. On the basis of the known theory of Ruppe and Blumenberg[1-3], nuclear power plants with turboelectric generators as well as solar-thermal power plants with parabolic or spheric mirrors are being analysed. The following thermodynamic processes are applied: the Rankine process, the Brayton process and—as an ideal comparative process—the Carnot process. An important parameter of the analysis for nuclear power plants is the net electric power, for the solar-thermal power plant the distance to the sun is of importance.

  18. Advanced gasification-based biomass power generation

    SciTech Connect

    Williams, R.H.; Larson, E.D. [Princeton Univ., NJ (United States)

    1993-12-31

    A promising strategy for modernizing bioenergy is the production of electricity or the cogeneration of electricity and heat using gasified biomass with advanced conversion technologies. Major advances that have been made in coal gasification technology, to marry the gas turbine to coal, are readily adaptable to biomass applications. Integrating biomass gasifiers with aeroderivative gas turbines in particular makes it possible to achieve high efficiencies and low unit capital costs at the modest scales required for bioenergy systems. Electricity produced with biomass-integrated gasifier/gas turbine (BIG/GT) power systems not only offers major environmental benefits but also would be competitive with electricity produced from fossil fuels and nuclear energy under a wide range of circumstances. Initial applications will be with biomass residues generated in the sugarcane, pulp and paper, and other agro- and forest-product industries. Eventually, biomass grown for energy purposes on dedicated energy farms will also be used to fuel these gas turbine systems. Continuing improvements in jet engine and biomass gasification technologies will lead to further gains in the performance of BIG/GT systems over the next couple of decades. Fuel cells operated on gasified biomass offer the promise of even higher performance levels in the period beyond the turn of the century. 79 refs., 21 figs., 11 tabs.

  19. Direct charge radioisotope activation and power generation

    DOEpatents

    Lal, Amit (Madison, WI); Li, Hui (Madison, WI); Blanchard, James P. (Madison, WI); Henderson, Douglass L. (Madison, WI)

    2002-01-01

    An activator has a base on which is mounted an elastically deformable micromechanical element that has a section that is free to be displaced toward the base. An absorber of radioactively emitted particles is formed on the base or the displaceable section of the deformable element and a source is formed on the other of the displaceable section or the base facing the absorber across a small gap. The radioactive source emits charged particles such as electrons, resulting in a buildup of charge on the absorber, drawing the absorber and source together and storing mechanical energy as the deformable element is bent. When the force between the absorber and the source is sufficient to bring the absorber into effective electrical contact with the source, discharge of the charge between the source and absorber allows the deformable element to spring back, releasing the mechanical energy stored in the element. An electrical generator such as a piezoelectric transducer may be secured to the deformable element to convert the released mechanical energy to electrical energy that can be used to provide power to electronic circuits.

  20. Generator powered electrically heated diesel particulate filter

    DOEpatents

    Gonze, Eugene V; Paratore, Jr., Michael J

    2014-03-18

    A control circuit for a vehicle powertrain includes a switch that selectivity interrupts current flow between a first terminal and a second terminal. A first power source provides power to the first terminal and a second power source provides power to the second terminal and to a heater of a heated diesel particulate filter (DPF). The switch is opened during a DPF regeneration cycle to prevent the first power source from being loaded by the heater while the heater is energized.

  1. The changing face of international power generation

    SciTech Connect

    Lindsay, I. [World Energy Council, London (United Kingdom)

    1997-12-31

    The author limits his remarks to a discussion of the international generator`s marketplace, especially aimed at the developing countries. He discusses future global electricity demand, generating capacity build, its financing issues, and to the commercial generating opportunities which now abound outside the US.

  2. Generating Functions for the Powers of Fibonacci Sequences

    ERIC Educational Resources Information Center

    Terrana, D.; Chen, H.

    2007-01-01

    In this note, based on the Binet formulas and the power-reducing techniques, closed forms of generating functions for the powers of Fibonacci sequences are presented. The corresponding results are extended to some other famous sequences as well.

  3. Modeling Generator Power Plant Portfolios and Pollution Taxes

    E-print Network

    Nagurney, Anna

    Modeling Generator Power Plant Portfolios and Pollution Taxes in Electric Power Supply Chain Networks: A Transportation Network Equilibrium Transformation K. Wu, Professor A. Nagurney, Z. Liu the Bad, Credit the Good · Climate change poses immense risks · Market failure: externalities need

  4. Power performance of US space radioisotope thermoelectric generators

    Microsoft Academic Search

    Gary L. Bennett; E. A. Skrabek

    1996-01-01

    Since 1961, the United States has flown 41 radioisotope thermoelectric generators (RTGs) and one reactor to provide power for 25 space power systems. Thirty-eight of these nuclear power sources on 22 space systems are still in space or on other planetary bodies. This paper summarizes the design and power performance of each of the basic RTG types that have been

  5. Solar thermal power systems. Annual technical progress report, FY 1979

    SciTech Connect

    Braun, Gerald W.

    1980-06-01

    The Solar Thermal Power Systems Program is the key element in the national effort to establish solar thermal conversion technologies within the major sectors of the national energy market. It provides for the development of concentrating mirror/lens heat collection and conversion technologies for both central and dispersed receiver applications to produce electricity, provide heat at its point of use in industrial processes, provide heat and electricity in combination for industrial, commercial, and residential needs, and ultimately, drive processes for production of liquid and gaseous fuels. This report is the second Annual Technical Progress Report for the Solar Thermal Power Systems Program and is structured according to the organization of the Solar Thermal Power Systems Program on September 30, 1979. Emphasis is on the technical progress of the projects rather than on activities and individual contractor efforts. Each project description indicates its place in the Solar Thermal Power Systems Program, a brief history, the significant achievements and real progress during FY 1979, also future project activities as well as anticipated significant achievements are forecast. (WHK)

  6. Technical and economical system comparison of photovoltaic and concentrating solar thermal power systems depending on annual global irradiation

    Microsoft Academic Search

    Volker Quaschning

    2004-01-01

    Concentrating solar thermal power and photovoltaics are two major technologies for converting sunlight to electricity. Variations of the annual solar irradiation depending on the site influence their annual efficiency, specific output and electricity generation cost. Detailed technical and economical analyses performed with computer simulations point out differences of solar thermal parabolic trough power plants, non-tracked and two-axis-tracked PV systems. Therefore,

  7. Thermal management system options for high power space platforms

    NASA Technical Reports Server (NTRS)

    Sadunas, J. A.; Lehtinen, A.; Parish, R.

    1985-01-01

    Thermal Management System (TMS) design options for a high power (75kWe), low earth orbit, multimodule space platform were investigated. The approach taken was to establish a baseline TMS representative of current technology, and to make incremental improvements through successive subsystem trades that lead to a candidate TMS. The TMS trades included centralized and decentralized transport, single-phase and two-phase transport, alternate working fluids, liquid loop and heat pipe radiators, deployed fixed, body mounted and steerable radiators, and thermal storage. The subsystem options were evaluated against criteria such as weight, TMS power requirement, reliability, system isothermality penalty, and growth potential.

  8. Two DOF controller for parallel operation of fuel cell power generator with power grid

    Microsoft Academic Search

    Junggi Lee; Jaihong Kim; Jungmin Kwon; Kwanghee Nam

    2005-01-01

    Parallel operation of a fuel cell power generator is considered in connection with the power grid. For a smooth power flow control between the local fuel cell generator system and the power grid, we propose a connection topology along with a two degree of freedom (DOF) controller. The two DOF controller inherently contains the inverse dynamics of the plant in

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

    SciTech Connect

    Kreider, M.A.; White, G.A.; Varrin, R.D. Jr. [Dominion Engineering, Inc., McLean, VA (United States)

    1998-06-01

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

  10. Cascade Failures in Power Grids with Distributed Generation

    NASA Astrophysics Data System (ADS)

    Scala, Antonio; Pahwa, Sakshi; Scoglio, Caterina; ISC Institute for Complex Systems Team; Department of Electrical and Computer Engineering Team

    2013-03-01

    Power grids are nowadays experiencing a transformation due to the introduction of Distributed Generation based on Renewable Sources. At difference with classical Distributed Generation, where local power sources mitigate anomalous user consumption peaks, Renewable Sources introduce in the grid intrinsically erratic power inputs. By introducing a simple schematic (but realistic) model for power grids with stochastic distributed generation, we study the effects of erratic sources on the robustness of several IEEE power grid test networks with up to 2 ×103 buses. We find that increasing the penetration of erratic sources causes the grid to fail with a sharp transition. We compare such results with the case of failures caused by the natural increasing power demand. Power grids are nowadays experiencing a transformation due to the introduction of Distributed Generation based on Renewable Sources. At difference with classical Distributed Generation, where local power sources mitigate anomalous user consumption peaks, Renewable Sources introduce in the grid intrinsically erratic power inputs. By introducing a simple schematic (but realistic) model for power grids with stochastic distributed generation, we study the effects of erratic sources on the robustness of several IEEE power grid test networks with up to 2 ×103 buses. We find that increasing the penetration of erratic sources causes the grid to fail with a sharp transition. We compare such results with the case of failures caused by the natural increasing power demand. US grant HDTRA1-11-1-0048, CNR-PNR National Project Crisis-Lab, US Department of Energy grant EE-0003812

  11. Experimental and numerical investigation of hydro power generator ventilation

    NASA Astrophysics Data System (ADS)

    Jamshidi, H.; Nilsson, H.; Chernoray, V.

    2014-03-01

    Improvements in ventilation and cooling offer means to run hydro power generators at higher power output and at varying operating conditions. The electromagnetic, frictional and windage losses generate heat. The heat is removed by an air flow that is driven by fans and/or the rotor itself. The air flow goes through ventilation channels in the stator, to limit the electrical insulation temperatures. The temperature should be kept limited and uniform in both time and space, avoiding thermal stresses and hot-spots. For that purpose it is important that the flow of cooling air is distributed uniformly, and that flow separation and recirculation are minimized. Improvements of the air flow properties also lead to an improvement of the overall efficiency of the machine. A significant part of the windage losses occurs at the entrance of the stator ventilation channels, where the air flow turns abruptly from tangential to radial. The present work focuses exclusively on the air flow inside a generator model, and in particular on the flow inside the stator channels. The generator model design of the present work is based on a real generator that was previously studied. The model is manufactured taking into consideration the needs of both the experimental and numerical methodologies. Computational Fluid Dynamics (CFD) results have been used in the process of designing the experimental setup. The rotor and stator are manufactured using rapid-prototyping and plexi-glass, yielding a high geometrical accuracy, and optical experimental access. A special inlet section is designed for accurate air flow rate and inlet velocity profile measurements. The experimental measurements include Particle Image Velocimetry (PIV) and total pressure measurements inside the generator. The CFD simulations are performed based on the OpenFOAM CFD toolbox, and the steady-state frozen rotor approach. Specific studies are performed, on the effect of adding "pick-up" to spacers, and the effects of the inlet fan blades on the flow rate through the model. The CFD results capture the experimental flow details to a reasonable level of accuracy.

  12. Ames Lab 101: Next Generation Power Lines

    SciTech Connect

    Russell, Alan

    2010-01-01

    Ames Laboratory scientist Alan Russell discusses the need to develop new power lines that are stronger and more conductive as a way to address the problem of the nation's aging and inadequate power grid.

  13. Ames Lab 101: Next Generation Power Lines

    ScienceCinema

    Russell, Alan

    2012-08-29

    Ames Laboratory scientist Alan Russell discusses the need to develop new power lines that are stronger and more conductive as a way to address the problem of the nation's aging and inadequate power grid.

  14. A thermally self-sustained micro solid-oxide fuel-cell stack with high power density

    E-print Network

    Haile, Sossina M.

    A thermally self-sustained micro solid-oxide fuel-cell stack with high power density Zongping Shao1 for portable power generation1,2 . Accordingly, polymer-electrolyte direct- methanol fuel cells). Anode-supported, thin-film electrolyte fuel cells were fabricated as reported elsewhere using samaria

  15. Generating expansion model incorporating compact DC power flow equations

    SciTech Connect

    Nderitu, D.G.; Sparrow, F.T.; Yu, Z. [Purdue Inst. for Interdisciplinary Engineering Studies, West Lafayette, IN (United States)

    1998-12-31

    This paper presents a compact method of incorporating the spatial dimension into the generation expansion problem. Compact DC power flow equations are used to provide real-power flow coordination equations. Using these equations the marginal contribution of a generator to th total system loss is formulated as a function of that generator`s output. Incorporating these flow equations directly into the MIP formulation of the generator expansion problem results in a model that captures a generator`s true net marginal cost, one that includes both the cost of generation and the cost of transport. This method contrasts with other methods that iterate between a generator expansion model and an optimal power flow model. The proposed model is very compact and has very good convergence performance. A case study with data from Kenya is used to provide a practical application to the model.

  16. Power enhancement of heat engines via correlated thermalization in multilevel systems

    E-print Network

    David Gelbwaser-Klimovsky; Wolfgang Niedenzu; Paul Brumer; Gershon Kurizki

    2014-11-05

    We analyze a heat machine based on a periodically-driven quantum system permanently coupled to hot and cold baths. It is shown that the maximal power output of a degenerate $V$-type three-level heat engine is that generated by two independent two-level systems. For $N$ levels, this maximal enhancement is $(N-1)$-fold. Hence, level degeneracy is a thermodynamic resource that may effectively boost the power output. The efficiency, however, is not affected. We find that coherence is not an essential asset in multilevel-based heat machines. The existence of multiple thermalization pathways sharing a common ground state suffices for power enhancement.

  17. Modular Analysis of Automobile Exhaust Thermoelectric Power Generation System

    NASA Astrophysics Data System (ADS)

    Deng, Y. D.; Zhang, Y.; Su, C. Q.

    2015-06-01

    In this paper, an automobile exhaust thermoelectric power generation system is packaged into a model with its own operating principles. The inputs are the engine speed and power, and the output is the power generated by the system. The model is divided into two submodels. One is the inlet temperature submodel, and the other is the power generation submodel. An experimental data modeling method is adopted to construct the inlet temperature submodel, and a theoretical modeling method is adopted to construct the power generation submodel. After modeling, simulation is conducted under various engine operating conditions to determine the variation of the power generated by the system. Finally, the model is embedded into a Honda Insight vehicle model to explore the energy-saving effect of the system on the vehicle under Economic Commission for Europe and cyc-constant_60 driving cycles.

  18. Science 101: How do windmills generate power?

    NSDL National Science Digital Library

    William C. Robertson, Ph.D.

    2009-07-01

    This is a timely question given that you can now buy your own windmill (or more correctly, wind turbine ) for residential use. More on that later. Using windmills to generate electricity makes sense once you understand how we generate electricity.

  19. IR scene image generation from visual image based on thermal database

    NASA Astrophysics Data System (ADS)

    Liao, Binbin; Wang, Zhangye; Ke, Xiaodi; Xia, Yibin; Peng, Qunsheng

    2007-11-01

    In this paper, we propose a new method to generate complex IR scene image directly from the corresponding visual scene image based on material thermal database. For the input visual scene image, we realize an interactive tool based on the combined method of global magic wand and intelligent scissors to segment the object areas in the scene. And the thermal attributes are assigned to each object area from the thermal database of materials. By adopting the scene infrared signature model based on infrared Physics and Heat Transfer, the surface temperature distribution of the scene are calculated and the corresponding grayscale of each area in IR image is determined by our transformation rule. We also propose a pixel-based RGB spacial similarity model to determine the mixture grayscales of residual area in the scene image. To realistically simulate the IR scene, we develop an IR imager blur model considering the effect of different resolving power of visual and thermal imagers, IR atmospheric noise and the modulation transfer function of thermal imager. Finally, IR scene images at different intervals under different weather conditions are generated. Compared with real IR scene images, our simulated results are quite satisfactory and effective.

  20. Underwater vehicle propulsion and power generation

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor); Chao, Yi (Inventor)

    2008-01-01

    An underwater vehicle includes a shaft with a propeller disposed thereon; a generator/motor having a stator and a rotor, the rotor being operable to rotate with the propeller; at least one energy storage device connected to the generator/motor; and a controller for setting the generator/motor in a charge mode, a propulsion mode and an idle mode.

  1. Two dimensional thermal and charge mapping of power thyristors

    NASA Technical Reports Server (NTRS)

    Hu, S. P.; Rabinovici, B. M.

    1975-01-01

    The two dimensional static and dynamic current density distributions within the junction of semiconductor power switching devices and in particular the thyristors were obtained. A method for mapping the thermal profile of the device junctions with fine resolution using an infrared beam and measuring the attenuation through the device as a function of temperature were developed. The results obtained are useful in the design and quality control of high power semiconductor switching devices.

  2. Nanosecond High Voltage Pulse Generator using Water Gap Switch for Compact High Power Pulsed Microwave Generator

    Microsoft Academic Search

    Y. Minamitani; Y. Ohe; Y. Higashiyama

    2006-01-01

    Nanosecond and subnanosecond high voltage pulses can provide new applications. A cancer treatment by ultra-short pulse high electric field is one of them. High power pulsed microwave has been proposed to apply the high electric field for that treatment. This work focuses on the design of a compact high power pulsed microwave generator using nanosecond pulse power generator for the

  3. Nanosecond High Voltage Pulse Generator Using Water Gap Switch for Compact High Power Pulsed Microwave Generator

    Microsoft Academic Search

    Yasushi Minamitani; Yoshinori Ohe; Yoshio Higashiyama

    2007-01-01

    Nanosecond and sub-nanosecond high voltage pulses can provide new applications. A cancer treatment by an ultra-short pulse high electric field is one of them. High power pulsed microwave has been proposed to apply the high electric field for that treatment. This work focuses on the design of a compact high power pulsed microwave generator using a nanosecond pulse power generator

  4. An all solid-state pulsed power generator based on Marx generator

    Microsoft Academic Search

    Kefu Liu; Jian Qiu; Yifan Wu; Xiaoxu Liu; Houxiu Xiao

    2007-01-01

    High voltage pulsed power supply with high repetitive rate has found wide applications in industry, and military such as plasma source for ion implantation, microwave generator and high pulsed power laser. The conventional pulsed power supply is limited by gas switch with short lifetime and low repetitive frequency. In recent years Marx generator based on solid state switches has proposed.

  5. Analytical thermal model validation for Cassini radioisotope thermoelectric generator

    SciTech Connect

    Lin, E.I. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.

    1997-12-31

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

  6. Optical Property Evaluation of Next Generation Thermal Control Coatings

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; Deshpande, Mukund S.; Pierson, Edward A.

    2010-01-01

    Next generation white thermal control coatings were developed via the Small Business Innovative Research program utilizing lithium silicate chemistry as a binder. Doping of the binder with additives yielded a powder that was plasma spray capable and that could be applied to light weight polymers and carbon-carbon composite surfaces. The plasma sprayed coating had acceptable beginning-of-life and end-of-live optical properties, as indicated by a successful 1.5 year exposure to the space environment in low Earth orbit. Recent studies also showed the coating to be durable to simulated space environments consisting of 1 keV and 10 keV electrons, 4.5 MeV electrons, and thermal cycling. Large scale deposition was demonstrated on a polymer matrix composite radiator panel, leading to the selection of the coating for use on the Gravity Recovery And Interior Laboratory (GRAIL) mission.

  7. Comparison of advanced thermal and electrical storage for parabolic dish solar thermal power systems

    Microsoft Academic Search

    T. Fujita; G. C. Birur; J. M. Schredder; J. M. Bowyer; H. I. Awaya

    1982-01-01

    Parabolic dish solar concentrator cluster concepts are explored, with attention given to thermal storage systems coupled to Stirling and Brayton cycle power conversion devices. Sensible heat storage involving molten salt (NaOH), liquid sodium, and solid cordierite bricks are considered for 1500 F thermal storage systems. Latent heat storage with NaF-MgF2 phase change materials are explored in terms of passive, active,

  8. Grumman evaluates Space Station thermal control and power systems

    Microsoft Academic Search

    Kandebo

    1985-01-01

    Attention is given to the definition of requirements for the NASA Space Station's electrical power and thermal control systems, which must be highly dependable to minimize the need for external support and will embody a highly flexible modular design concept. Module maintenance will be performed by in-orbit replacement of failed modules, and energy storage system growth will be accomplished by

  9. Decision support system for thermal power plant siting (SDSS)

    Microsoft Academic Search

    Wang Guangsheng; Hu Zhaoguang; Wang Pingyang

    1993-01-01

    On the basis of new technologies such as fuzzy sets, analytic hierarchy process and expert systems etc., a practical decision support system for thermal power plant siting (SDSS) has been set up and is presented in this paper. SDSS, as displayed on the PC screen, consists of ten parts: introduction, system maintenance, individual decision, clear database, consultation, auxiliary operation, multiple

  10. Passivation of silicon power devices by thermal oxidation

    Microsoft Academic Search

    A. Neidig; G. Wahl; K. Weimann; G. Gilbers

    1979-01-01

    A method was developed for the passivation of high voltage silicon power devices replacing the usually applied sensitive silicon polymers on the edge beveling of the pn junctions. The new passivation is produced at temperatures between 600 C and 900 C by thermal oxidation followed by chemical vapor deposition of a barrier layer against alkaline impurities. The barrier layers are

  11. Parabolic Dish Solar Thermal Power Annual Program Review Proceedings

    NASA Technical Reports Server (NTRS)

    Lucas, J. W.

    1982-01-01

    The results of activities of the parabolic dish technology and applications development element of DOE's Solar Thermal Energy System Program are presented. Topics include the development and testing of concentrators, receivers, and power conversion units; system design and development for engineering experiments; economic analysis and marketing assessment; and advanced development activities. A panel discussion concerning industrial support sector requirements is also documented.

  12. Balance of Power: Dynamic Thermal Management for Internet Data Centers

    Microsoft Academic Search

    Ratnesh K. Sharma; Cullen E. Bash; Chandrakant D. Patel; Richard J. Friedrich; Jeffrey S. Chase

    2005-01-01

    The advent of Internet -based applications and their resulting multi-tier distributed architecture has changed the focus of design for large -scale Internet computing. Internet server applications execute in a horizontally scalable topology across hundreds or thousands of commodity servers in an Internet data center. Increasing scale and power density have a significant impact on the thermal properties of the data

  13. Probabilistic projection of nuclear and coal electric power generation costs

    Microsoft Academic Search

    K. A. Williams; J. G. Delene

    1987-01-01

    This paper presents the results of an analysis of future nuclear and coal-fired plant power generation costs in which the probability distributions of key variables are used with a Monte Carlo driver code to obtain power generation cost distributions for the options. The resulting distributions are compared to deterministic estimates based on recommended parameters given in the US Dept. of

  14. Full range nuclear power plant steam generator level control system

    Microsoft Academic Search

    Geets

    1988-01-01

    In a method of controlling feedwater level in a steam generator of a pressurized water reactor nuclear power plant, the steam generator having secondary loop feedwater lines. The method is described including the steps of outputting a first signal from a first three-mode controller to control feedwater flow through the secondary loop feedwater lines at reactor power levels below a

  15. Solar Stirling Dish Power Generation Atlas of India

    Microsoft Academic Search

    T. Krishnaiah; S. Srinivasa Rao; K. Madhumurthy

    2009-01-01

    In this article, an atlas of solar electricity potential of Stirling dish power generation system is presented. Important parameters needed for solar power generation modeling are direct solar insolation, ambient temperature, wind speed, concentrator aperture area, rim angle, mirror reflectance, working fluid, operating temperature, receiver insulating material and intercept factor. The input data values averaged over a 10-year period is

  16. DOWNHOLE POWER GENERATION AND WIRELESS COMMUNICATIONS FOR INTELLIGENT COMPLETIONS APPLICATIONS

    SciTech Connect

    Paul Tubel

    2004-02-01

    The development work during this quarter was focused in the assembly of the downhole power generator hardware and its electronics module. The quarter was also spent in the development of the surface system electronics and software to extract the acoustic data transmitted from downhole to the surface from the noise generated by hydrocarbon flow in wells and to amplify very small acoustic signals to increase the distance between the downhole tool and the surface receiver. The tasks accomplished during this report period were: (1) Assembly of the downhole power generator mandrel for generation of electrical power due to flow in the wellbore. (2) Test the piezoelectric wafers to assure that they are performing properly prior to integrating them to the mechanical power generator mandrel. (3) Coat the power generator wafers to prevent water from shorting the power generator wafers. (4) Test of the power generator using a water tower and an electric pump to create a water flow loop. (5) Test the power harvesting electronics module. (6) Upgrade the signal condition and amplification from downhole into the surface system. (7) Upgrade the surface processing system capability to process data faster. (8) Create a new filtering technique to extract the signal from noise after the data from downhole is received at the surface system.

  17. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

    Microsoft Academic Search

    LC BROWN; GE BESENBRUCH; KR SCHULTZ; JF FUNK; PS PICKARD; AC MARSHALL; SK SHOWALTER

    2003-01-01

    OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of

  18. Numerical and Experimental Optimization of Thermoelectric Modules for Power Generation

    E-print Network

    Rosendahl, Lasse

    Numerical and Experimental Optimization of Thermoelectric Modules for Power Generation Min Chen1 as a whole has not been available. This paper is to study the optimal design of thermoelectric generator: In the application of thermoelectric power technique, the term optimization in a broad sense involves the design

  19. Comparison of electrochemical and thermal storage for hybrid parabolic dish solar power plants

    NASA Technical Reports Server (NTRS)

    Steele, H. L.; Wen, L.

    1981-01-01

    The economic and operating performance of a parabolic point focus array of solar electricity generators combined with either battery or thermal energy storage are examined. Noting that low-cost, mass-producible power generating units are under development for the point focus of distributed dishes, that Zn-Cl battery tests will begin in 1981 and a 100 kWh Na-S battery in 1983, the state of thermal storage requires acceleration to reach the prototype status of the batteries. Under the assumptions of 10,000 units/yr with an expected 30 yr lifetime, cost comparisons are developed for 10 types of advanced batteries. A 5 MWe plant with full thermal or 80% battery storage discharge when demand occurs in conditions of no insolation is considered, specifically for Fe-Cr redox batteries. A necessity for the doubling of fuel prices from 1980 levels by 1990 is found in order to make the systems with batteries economically competitive.

  20. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

    SciTech Connect

    BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

    2003-06-01

    OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could benefit, in terms of efficien

  1. Addressing thermal and power delivery bottlenecks in 3D circuits

    Microsoft Academic Search

    Sachin S. Sapatnekar

    2009-01-01

    The enhanced packing densities facilitated by 3D integrated circuit technology also has an unwanted side-effect, in the form of increasing the amount of current per unit footprint of the chip, as compared to a 2D design. This has ramifications on two critical issues: firstly, it means that more heat is generated per unit footprint, potentially leading to thermal problems, and

  2. POWER SCHEDULING IN A HYDRO-THERMAL SYSTEM UNDER UNCERTAINTY

    E-print Network

    Römisch, Werner

    , generator outages, stream ows in water units, and prices or mar- ket situations in general. The latter and pumped-storage hydro units is developed. For its compu- tational solution two di erent decompo- sition-burning) thermal units, pumped-storage hydro plants and delivery con- tracts and describe an optimization model

  3. Nuclear power generation and fuel cycle report 1997

    SciTech Connect

    NONE

    1997-09-01

    Nuclear power is an important source of electric energy and the amount of nuclear-generated electricity continued to grow as the performance of nuclear power plants improved. In 1996, nuclear power plants supplied 23 percent of the electricity production for countries with nuclear units, and 17 percent of the total electricity generated worldwide. However, the likelihood of nuclear power assuming a much larger role or even retaining its current share of electricity generation production is uncertain. The industry faces a complex set of issues including economic competitiveness, social acceptance, and the handling of nuclear waste, all of which contribute to the uncertain future of nuclear power. Nevertheless, for some countries the installed nuclear generating capacity is projected to continue to grow. Insufficient indigenous energy resources and concerns over energy independence make nuclear electric generation a viable option, especially for the countries of the Far East.

  4. Heat engine development for solar thermal power systems

    NASA Technical Reports Server (NTRS)

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

    1981-01-01

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

  5. High power density alkali metal thermal to electric converter

    NASA Astrophysics Data System (ADS)

    Sievers, R. K.; Wright, R. F.

    A description is given of the alkali metal thermal-to-electric converter (AMTEC), an emerging technology for static power conversion that has the potential of matching dynamic system efficiency. This high efficiency is produced when cells of beta double prime alumina solid electrolyte (BASE) are series connected, packed in a space-efficient manner, and designed to minimize parasitic heat loss. Design studies have shown that power densities of up to 400 W/kg and efficiencies of up to 35 percent are feasible. This is higher than power densities and efficiencies reported for other AMTEC designs, but continued design studies are necessary to assess applications.

  6. Future Photovoltaic Power Generation for Space-Based Power Utilities

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Landis, Geoffrey; Hepp, Aloysius; Raffaelle, Ryne

    2002-01-01

    This paper discusses requirements for large earth orbiting power stations that can serve as central utilities for other orbiting spacecraft, or for beaming power to the earth itself. The current state of the art of space solar cells, and a variety of both evolving thin film cells as well as new technologies that may impact the future choice of space solar cells for high power mission applications are addressed.

  7. Solar powered Stirling cycle electrical generator

    Microsoft Academic Search

    Richard K. Shaltens

    1991-01-01

    Under NASA's Civil Space Technology Initiative (CSTI), the NASA Lewis Research Center is developing the technology needed for free-piston Stirling engines as a candidate power source for space systems in the late 1990's and into the next century. Space power requirements include high efficiency, very long life, high reliability, and low vibration. Furthermore, system weight and operating temperature are important.

  8. Power loss in AMTEC, an advanced space power generation cell

    NASA Astrophysics Data System (ADS)

    Lodhi, M. A. K.; Vijayaraghavan, P.; Chaudhury, M. S.

    2001-03-01

    Recently a lot of work has been done in designing the Alkali Metal Thermo Electric Converter (AMTEC), a power cell, primarily aimed at for deep space exploration, and later on for terrestrial use. During an extended testing of AMTEC the maximum power output was found rapidly decreasing (more so in the begining) with time. This is one of the major problems yet to overcome in AMTEC technology before it could be used for deep space expolration. We have throughly analyzed AMTEC by computer simulation and identified major causes for power degradation associated with its components namely, its electrolyte and electrodes. Some suggestions are offered to reduce the power degradation rate.

  9. Active thermal control for an advanced power platform

    NASA Technical Reports Server (NTRS)

    Owen, J. W.; Stein, D. S.

    1981-01-01

    Effective use of the Shuttle Orbiter during the operational phase will require the provision of electrical power from free-flying power platforms which will interface with the Orbiter. Such platforms present unique requirements for active thermal control based upon the long life and high heat load requirements which will be necessary to provide 25 kW or more of electricity to the Orbiter and payloads. This paper will present key issues in the design of these active thermal control systems (ATCS) and will discuss potential solutions intended to ensure maximum effectiveness of advanced power platforms. Such issues include proper selection of coolant fluid for the power platform and payload loops; selection and development of thermal control surfaces for five-year life; the use of off-the-shelf hardware vs development of unique hardware, central vs decentralized control of the ATCS; system life and reliability as a factor in determining redundancy and the possibility of on-orbit EVA maintenance; and the interfaces between the power platform and the Orbiter and payloads.

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

  11. Thermal effects in high average power optical parametric amplifiers.

    PubMed

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

    2013-03-01

    Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given. PMID:23455291

  12. Effect of thermal power plant emissions on Catharanthus roseus L

    SciTech Connect

    Khan, A.M.; Pandey, V.; Shukla, J.; Singh, N.; Yunus, M.; Singh, S.N.; Ahmad, K.J. (National Botanical Research Institute, Lucknow (India))

    1990-06-01

    Most of the industrialized nations depend largely on the combustion of fossil fuels for their energy requirements. During the past few years in India quite a few thermal power plants have been commissioned to cater to the increasing energy requirements. As most of the power plants are coal-fired, a complex mixture of several pollutants is released in the atmosphere on the combustion of coal. Leaves by virtue of their unique position on plants and their functions, experience the maximum brunt of exposure and undergo certain changes in form, structure and function with the changes in surrounding environs, and such modifications are likely to serve as markers of environmental pollution. The present paper deals with the long term exposure effects of thermal power plant emissions on Catharanthus roseus L. - a common perennial shrub, with glossy leaves and white, mauve or pink colored flowers and of great medicinal value is grown as an ornamental plant all over the country.

  13. Alternative approaches to space-based power generation

    NASA Technical Reports Server (NTRS)

    Gregory, D. L.

    1977-01-01

    Satellite Power Stations (SPS) would generate electrical power in space for terrestrial use. Their geosynchronous orbit location permits continuous microwave power transmission to ground receiving antenna farms. Eight approaches to the generation of the electrical power to be transmitted were investigated. Configurations implementing these approaches were developed through an optimization process intended to yield the lowest cost for each. A complete program was baselined for each approach, identifying required production rates, quantities of launches, required facilities, etc. Each program was costed, including the associated launches, orbital assembly, and maintenance operations. The required electric power charges to amortize these costs were calculated. They range from 26 to 82 mills/kWh (ground busbar).

  14. Nuclear power generation and fuel cycle report 1996

    SciTech Connect

    NONE

    1996-10-01

    This report presents the current status and projections through 2015 of nuclear capacity, generation, and fuel cycle requirements for all countries using nuclear power to generate electricity for commercial use. It also contains information and forecasts of developments in the worldwide nuclear fuel market. Long term projections of U.S. nuclear capacity, generation, and spent fuel discharges for two different scenarios through 2040 are developed. A discussion on decommissioning of nuclear power plants is included.

  15. Introduction of Car Alternators for Small Scale Wind Power Generation

    Microsoft Academic Search

    Nanayakkara D. P. N

    Generally Permanent Magnet Generators (PMGs) are widely used for small-scale wind power generation. But in Sri Lanka, it is difficult to find a competitive market for such generators and permanent magnets, since the price of a PMG is very high and is very rare.Due to such conditions, expansion of small-scale wind power applications among rural communities are significantly limited. The

  16. The Role of Nuclear Power in Global Electricity Generation

    Microsoft Academic Search

    M. Balat

    2007-01-01

    Nuclear technology plays an important role in medicine, industry, science, food and agriculture, and power generation. Nuclear power plants (NPPs) are structured like other power plants, except that they use energy from nuclear fission to produce electricity. Nuclear energy is a very clean energy if it is well designed, well built, well operated, and well managed. It has no atmospheric

  17. Control of an optimized converter for modular solar power generation

    Microsoft Academic Search

    R. Schmidt; F. Jenni; J. Riatsch

    1994-01-01

    Important drawbacks of solar power generation are the DC-wiring and fusing needed for the serial and parallel connection of solar panels. These problems can be reduced to AC wiring and fusing by using a modular set up of panels together with integrated single phase DC-AC power converters on a power level of approximately 200 W. A general applicable model has

  18. Development of a renewable hybrid power generation system

    Microsoft Academic Search

    Chi Cheung; K. Bengtson; M. Moser; A. Wu; B. Parrilla; C. Mastrangelo

    2009-01-01

    A renewable hybrid power generation system is proposed. The motivation for the system is that grid power is often unreliable, limited or even nonexistent remote\\/rural areas such as forward operating bases and schools and hospitals in developing countries. The challenge of this system is to provide a reliable, cost-effective power management system that is scalable and uses renewable energy sources.

  19. Wind energy-hydrogen storage hybrid power generation

    Microsoft Academic Search

    Wen-Jei Yang; Orhan Aydin

    2001-01-01

    SUMMARY In this theoretical investigation, a hybrid power generation system utilizing wind energy and hydrogen storage is presented. Firstly, the available wind energy is determined, which is followed by evaluating the e$ciency of the wind energy conversion system. A revised model of windmill is proposed from which wind power density and electric power output are determined. When the load demand

  20. Micromachined CMOS thermoelectric generators as on-chip power supply

    Microsoft Academic Search

    M. Strasser; R. Aigner; C. Lauterbach; T. F. Sturm; M. Franosch; G. Wachutka

    2004-01-01

    As the power consumption of a large number of microelectronic devices has been continuously reduced in recent years, power supply units of a few microwatts have become sufficient for their operation. Our improved micro-scale thermoelectric generator (?-TEG) is based on polysilicon surface micromachining and is designed to convert waste heat into electrical power. Since this device is compatible with standard

  1. Micromachined CMOS thermoelectric generators as on-chip power supply

    Microsoft Academic Search

    M. Strasser; R. Aigner; C. Lauterbach; T. F. Sturm; M. Franosh; G. Wachutka

    2003-01-01

    As the power consumption of a large number of microelectronic devices has been continuously reduced in recent years, power supply units of a few microwatts have become sufficient for their operation. Our improved micro-scale thermoelectric generator (?-TEG) is based on polysilicon surface micromachining and is designed to convert waste heat into electrical power. Since this device is compatible with standard

  2. Optimal distributed power generation under network load constraints

    E-print Network

    Utrecht, Universiteit

    , mainly because of the development of novel components for decentral power generation (solar panels, small wind turbines and heat pumps). This gives rise to the question how many units of each type (solar panel Abstract. In electrical power networks nowadays more and more customers are becoming power- producers

  3. Power generation by exchange of latent heats of phase transition

    Microsoft Academic Search

    S. Ehrlich; W. L. Levenson

    1981-01-01

    A power system is provided that uses the latent heat of fusion of water to raise the potential energy of a working fluid to a level that upon release generates power, preferably electrical power. The system is self-sustaining except for the energy that is supplied in water entering the system. The inlet water can be at any temperature within its

  4. Thermoelectric Generators using Solar Thermal Energy in Heated Road Pavement

    Microsoft Academic Search

    M. Hasebe; Y. Kamikawa; S. Meiarashi

    2006-01-01

    The temperature of road pavement rises up to 70degC in summer due to the effect of the solar radiation. The authors have developed a pavement-cooling system using thermoelectric generator. Heat in the pavement is collected as heated water in a heat collection tube installed in the pavement. River water near the road is used as a coolant. Electric power is

  5. Power loss in AMTEC, an advanced space power generation cell

    Microsoft Academic Search

    M. A. K. Lodhi; P. Vijayaraghavan; M. S. Chaudhury

    2001-01-01

    Recently a lot of work has been done in designing the Alkali Metal Thermo Electric Converter (AMTEC), a power cell, primarily aimed at for deep space exploration, and later on for terrestrial use. During an extended testing of AMTEC the maximum power output was found rapidly decreasing (more so in the begining) with time. This is one of the major

  6. Thermoelectric Power Generation Allison Duh and Joel Dungan

    E-print Network

    Lavaei, Javad

    Thermoelectric Power Generation Allison Duh and Joel Dungan May 15, 2013 #12;Introduction A thermoelectric generator (TEG) is a device that converts heat energy directly into electrical energy, the thermoelectric effects relevant to understanding TEG operation are introduced. A simple thermoelectric generator

  7. 2. Credit PEM. View of Martinsburg Power Company steam generating ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Credit PEM. View of Martinsburg Power Company steam generating plant. From right to left: original 1889 generating building, transformer room, new generating room and, adjacent to draft stack is boiler room addition. Photo c. 1911. - Dam No. 4 Hydroelectric Plant, Potomac River, Martinsburg, Berkeley County, WV

  8. Voltage versus VAr\\/power factor regulation on synchronous generators

    Microsoft Academic Search

    Thomas W. Eberly; Richard C. Schaefer

    2002-01-01

    When paralleled to the utility bus, synchronous generators can be controlled using either terminal voltage or VAr\\/power factor control. Selection is dependent upon the size of the generator and the stiffness of the connecting utility bus. For large generators where the kVA is significant, these machines are usually terminal voltage regulated and dictate the system's bus voltage. When smaller terminal

  9. Microwave power generation by magnetic superlattices

    NASA Astrophysics Data System (ADS)

    Littlejohn, S.; Nogaret, A.; Davies, S. R.; Henini, M.; Beere, H. E.; Ritchie, D. A.

    2011-12-01

    We report on microwave power emission by ballistic electrons as they cross a region of spatially inhomogeneous magnetic field. Magnetic finger gates were fabricated at the surface of high mobility GaAs/AlGaAs Hall bars embedded in a coplanar waveguide. By modulating the current injected through the Hall bar and measuring the second harmonic of the signal rectified by a Schottky detector, we obtain the microwave power emitted by the superlattice. This power (˜6 W m-2) is compared to the fluorescence of electron spins that undergo spin resonance as they cross domains of opposite magnetic field.

  10. Lifetime prediction modeling of airfoils for advanced power generation

    NASA Astrophysics Data System (ADS)

    Karaivanov, Ventzislav Gueorguiev

    The use of gases produced from coal as a turbine fuel offers an attractive means for efficiently generating electric power from our Nation's most abundant fossil fuel resource. The oxy-fuel and hydrogen-fired turbine concepts promise increased efficiency and low emissions on the expense of increased turbine inlet temperature (TIT) and different working fluid. Developing the turbine technology and materials is critical to the creation of these near-zero emission power generation technologies. A computational methodology, based on three-dimensional finite element analysis (FEA) and damage mechanics is presented for predicting the evolution of creep and fatigue in airfoils. We took a first look at airfoil thermal distributions in these advanced turbine systems based on CFD analysis. The damage mechanics-based creep and fatigue models were implemented as user modified routine in commercial package ANSYS. This routine was used to visualize the creep and fatigue damage evolution over airfoils for hydrogen-fired and oxy-fuel turbines concepts, and regions most susceptible to failure were indentified. Model allows for interaction between creep and fatigue damage thus damage due to fatigue and creep processes acting separately in one cycle will affect both the fatigue and creep damage rates in the next cycle. Simulation results were presented for various thermal conductivity of the top coat. Surface maps were created on the airfoil showing the development of the TGO scale and the Al depletion of the bond coat. In conjunction with model development, laboratory-scale experimental validation was executed to evaluate the influence of operational compressive stress levels on the performance of the TBC system. TBC coated single crystal coupons were exposed isothermally in air at 900, 1000, 1100oC with and without compressive load. Exposed samples were cross-sectioned and evaluated with scanning electron microscope (SEM). Performance data was collected based on image analysis. Energy-dispersive x-ray (EDX) was employed to study the elemental distribution in TBC system after exposure. Nanoindentation was used to study the mechanical properties (Young's modulus and hardness) of the components in the TBC system and their evolution with temperature and time.

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

    NASA Technical Reports Server (NTRS)

    Cherry, W. R.

    1971-01-01

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

  12. Thermally regenerative hydrogen/oxygen fuel cell power cycles

    NASA Astrophysics Data System (ADS)

    Morehouse, J. H.

    1986-07-01

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

  13. Opening New Frontiers in Power Generation

    E-print Network

    Haile, Sossina M.

    #12;F uel cells initially found application in space exploration, opening new frontiers by virtue Systems Work F uel cells produce power electro- chemically by passing a hydro- gen-rich gas over an anode

  14. Thermally Generated Point Defects in Silicon Dioxide Films.

    NASA Astrophysics Data System (ADS)

    Zvanut, M. E.; Chen, T. L.; Stahlbush, R. E.; Steigerwalt, E. S.

    1996-03-01

    Despite the growing number of competing microelectronic materials, silicon dioxide films on Si remain the most commonly used system for electronic applications. While previous studies address radiation-induced and growth-induced defects in these films, our electron paramagnetic resonance results reveal two different point defects generated by 1000^circC post growth annealing in a moisture free environment. One at g = 2.0026 appears immediately after annealing, is stable at room temperature, and may be similar to the Ex center found in vacuum annealed thin thermal oxides. A second defect, the multiple oxygen vacancy related E'_? center, appears only after thermal treatment and x-ray irradiation. The density of the E'_? center is independent of oxide thickness between 100 and 400 nm and is unstable at room temperature. The dependence on ambient moisture will be discussed in terms of the out-diffusion of H_2O and generation of SiO. Selected samples were supplied by G. Brown, Texas Instruments.

  15. Microcombustor-thermoelectric power generator for 10-50 watt applications

    NASA Astrophysics Data System (ADS)

    Marshall, Daniel S.; Cho, Steve T.

    2010-04-01

    Fuel-based portable power systems, including combustion and fuel cell systems, take advantage of the 80x higher energy density of fuel over lithium battery technologies and offer the potential for much higher energy density power sources - especially for long-duration applications, such as unattended sensors. Miniaturization of fuel-based systems poses significant challenges, including processing of fuel in small channels, catalyst poisoning, and coke and soot formation. Recent advances in micro-miniature combustors in the 200Watt thermal range have enabled the development of small power sources that use the chemical energy of heavy fuel to drive thermal-to-electric converters for portable applications. CUBE Technology has developed compact Micro-Furnace combustors that efficiently deliver high-quality heat to optimized thermal-to-electric power converters, such as advanced thermoelectric power modules and Stirling motors, for portable power generation at the 10-50Watt scale. Key innovations include a compact gas-gas recuperator, innovative heavy fuel processing, coke- & soot-free operation, and combustor optimization for low balance-of-plant power use while operating at full throttle. This combustor enables the development of robust, high energy density, miniature power sources for portable applications.

  16. The Feasibility of a Current-Source Thermoelectric Power Generator and Its Corresponding Structure Design

    NASA Astrophysics Data System (ADS)

    Wu, Guangxi; Yu, Xiong

    2015-06-01

    Traditional thermoelectric power generators consist of thermoelectric elements connected electrically in series and thermally in parallel. Current flowing inside the thermoelectric power generator is conventionally considered to be driven by the Seebeck effect-induced electric field and the output voltage-induced reverse electric field. This paper proposes a more comprehensive model that implies that current is also driven by chemical potential and carrier density variation. Therefore, the thermoelectric power generator can be treated as a current-source power supplier when the current driven by carrier density variation dominates. This paper performs holistic finite element implementation of the new holistic model where a thermoelectric power generator unit behaves like a current-source while the working temperature conditions maintain stability. This result validates that the thermoelectric element shows the behaviors of a current-source power supply under certain conditions. This discovery brings a new perspective on the behaviors of thermoelectric elements, which potentially will lead to the development of novel thermoelectric power generator design.

  17. Monolithic fuel cell based power source for sprint power generation

    NASA Astrophysics Data System (ADS)

    Fee, D. C.; Busch, D. E.; Dees, D. W.; Dusek, J.; Easler, T. E.; Ellingson, W. A.; Flandermeyer, B. K.; Fousek, R. J.; Heiberger, J. J.; Majumdar, S.

    A unique fuel cell (monolith) coupled with a low power nuclear reactor presents an attractive approach for SDI burst power requirements. The high power, long duration bursts, appear achievable within a single shuttle launch limitation with appropriate development of the concept. The feasibility of the monolithic fuel cell concept has been demonstrated. Small arrays (stacks) of the monolithic design have been operated for hundreds of hours. The challenge is to improve the fabrication technology so that larger array of the monolithic design can be operated.

  18. Generation of high-power subnanosecond pulses

    Microsoft Academic Search

    G. A. Mesyats; S. N. Rukin; V. G. Shpak; M. I. Yalandin

    1998-01-01

    The generation of short (0.1-1.0 ns) pulses based on spark gaps remained for a long time the only type of low impedance (<100 Ohm) subnanosecond devices capable of producing an output voltage of 100 kV and more. The developments in subnanosecond pulse generation are briefly outlined. The results of fundamental importance obtained in a series of experiments on studying the

  19. Compensation of Strong Thermal Lensing in High Optical Power Cavities

    E-print Network

    C. Zhao; J. Degallaix; L. Ju; Y. Fan; D. G. Blair; B. J. J. Slagmolen; M. B. Gray; C. M. Mow Lowry; D. E. McClellandl; D. J. Hosken; D. Mudge; A. Brooks; J. Munch; P. J. Veitch; M. A. Barton; G. Billingsley

    2006-02-28

    In an experiment to simulate the conditions in high optical power advanced gravitational wave detectors such as Advanced LIGO, we show that strong thermal lenses form in accordance with predictions and that they can be compensated using an intra-cavity compensation plate heated on its cylindrical surface. We show that high finesse ~1400 can be achieved in cavities with internal compensation plates, and that the cavity mode structure can be maintained by thermal compensation. It is also shown that the measurements allow a direct measurement of substrate optical absorption in the test mass and the compensation plate.

  20. Thermal emission in fatigue described by power laws

    NASA Astrophysics Data System (ADS)

    Curti, G.; Curã, F.; Gallinatti, A. E.; Sesana, R.

    2010-06-01

    In the present work, a theoretical model proposed by the literature and focused on the relationship between microplasticizations thermal behaviour and fatigue scatter is analysed and applied to fatigue test results of standard and notched steel specimens. The same experimental data are subjected to the TCM (Two Curves Method) thermographic elaboration technique, in order to quickly evaluate fatigue limit values. TCM method has been modified, aiming at interpolating thermal data referred to the region of loads upper than fatigue limit with a non linear regression law having the same mathematical structure of the theoretical model equations (power laws).

  1. Coupling an induction motor type generator to ac power lines. [making windmill generators compatible with public power lines

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (inventor)

    1984-01-01

    A system for coupling an induction motor type generator to an A.C. power line includes an electronic switch means that is controlled by a control system and is regulated to turn on at a relatively late point in each half cycle of its operation. The energizing power supplied by the line to the induction motor type generator is decreased and the net power delivered to the line is increased.

  2. Combined fuel and air staged power generation system

    SciTech Connect

    Rabovitser, Iosif K; Pratapas, John M; Boulanov, Dmitri

    2014-05-27

    A method and apparatus for generation of electric power employing fuel and air staging in which a first stage gas turbine and a second stage partial oxidation gas turbine power operated in parallel. A first portion of fuel and oxidant are provided to the first stage gas turbine which generates a first portion of electric power and a hot oxidant. A second portion of fuel and oxidant are provided to the second stage partial oxidation gas turbine which generates a second portion of electric power and a hot syngas. The hot oxidant and the hot syngas are provided to a bottoming cycle employing a fuel-fired boiler by which a third portion of electric power is generated.

  3. Advanced generators used in mobile pulsed power sources

    NASA Astrophysics Data System (ADS)

    Zhelokova, M. Z.; Maksimova, I. F.

    2010-12-01

    In this paper consideration is given to the versions of electric generators that are used for supplying high-power energy-intensive loads by means of capacitive or inductive energy storage units and are to be employed in mobile power sources. An estimate of limiting power characteristics of megajoule high-speed engines is presented that may be useful in developing a design assignment for construction of suitable engines, and, on their basis, forced power sources for supplying non-typical consumers.

  4. Automatic Power Model Generation for Sensor Network Simulator

    Microsoft Academic Search

    Hyunwoo Joe; Hyungshin Kim

    2007-01-01

    Energy consumption estimation in sensor network is a critical process for network lifetime estimation before actual deployment.\\u000a Energy consumption can be estimated by simulating the sensor network with a power model. Power model is the key component\\u000a for the accurate estimation. However, the power model is not publicly accessible and it is not easy to generate accurate fine-grain\\u000a power model.

  5. Cascade Failures from Distributed Generation in Power Grids

    E-print Network

    Scala, Antonio; Scoglio, Caterina

    2012-01-01

    Power grids are nowadays experiencing a transformation due to the introduction of Distributed Generation based on Renewable Sources. At difference with classical Distributed Generation, where local power sources mitigate anomalous user consumption peaks, Renewable Sources introduce in the grid intrinsically erratic power inputs. By introducing a simple schematic (but realistic) model for power grids with stochastic distributed generation, we study the effects of erratic sources on the robustness of several IEEE power grid test networks with up to 2000 buses. We find that increasing the penetration of erratic sources causes the grid to fail with a sharp transition. We compare such results with the case of failures caused by the natural increasing power demand.

  6. Thermal hydraulic analysis\\/data comparisons of two U-tube steam generators using the ATHOS3 code

    Microsoft Academic Search

    L. W. Keeton; S. D. Habchi; A. K. Singhal; G. Srikantiah

    1987-01-01

    This paper describes numerical simulations of two full-scale, U-Tube steam generators of the Westinghouse Model 51-type. The selected generators are instrumented and operated by Electricite de France (EdF) at the Bugey-4 and Tricastin-1 power plants. The computer code used is ATHOS3, which is designed for three-dimensional, two-phase, steady-state and transient thermal-hydraulic analysis of U-Tube I (UTSG) and Once-Through (OTSG) steam

  7. ATHOS: a computer program for thermal-hydraulic analysis of steam generators. Volume 2. Programmer's manual

    SciTech Connect

    Singhal, A.K.; Keeton, L.W.; Przekwas, A.J.; Weems, J.S.

    1982-10-01

    ATHOS (Analysis of the Thermal Hydraulics of Steam Generators) is a computer code developed by CHAM of North America Incorporated, under the contract RP 1066-1 from the Electric Power Research Institute, Palo Alto, California. ATHOS supercedes the earlier code URSULA2. ATHOS is designed for three-dimensional, steady-state and transient analyses of PWR steam generators. The current version of the code has been checked out for: three different configurations of the recirculating-type U-tube steam generators; the homogeneous and algebraic-slip flow models; and full and part load operating conditions. The description of ATHOS is divided into the following four volumes: Volume 1, Mathematical and Physical Models and Methods of Solution; Volume 2, Programmer's Manual; Volume 3, User's Manual; and Volume 4, Applications. The code's possible uses, capabilities and limitations are described in Volume 1 as well as in Volume 3.

  8. Two-Dimensional Thermal Resistance Analysis of a Waste Heat Recovery System with Thermoelectric Generators

    NASA Astrophysics Data System (ADS)

    Huang, Gia-Yeh; Yao, Da-Jeng

    2013-07-01

    In this study, it is shown that two-dimensional (2D) thermal resistance analysis is a rapid and simple method to predict the power generated from a waste heat recovery system with thermoelectric generators (TEGs). Performance prediction is an important part of system design, generally being simulated by numerical methods with high accuracy but long computational duration. Use of the presented analysis saves much time relative to such numerical methods. The simple 2D model of the waste heat recovery system comprises three parts: a recovery chamber, the TEGs, and a cooling system. A fin-structured duct serves as a heat recovery chamber, to which were attached the hot sides of two TEGs; the cold sides were attached to a cooling system. The TEG module and duct had the same width. In the 2D analysis, unknown temperatures are located at the centroid of each cell into which the system is divided. The relations among the unknown temperatures of the cells are based on the principle of energy conservation and the definition of thermal resistance. The temperatures of the waste hot gas at the inlet and of the ambient fluid are known. With these boundary conditions, the unknown temperatures in the system become solvable, and the power generated by the TEGs can be predicted. Meanwhile, a three-dimensional (3D) model of the system was simulated in FloTHERM 9.2. The 3D numerical solution matched the solution of the 2D analysis within 10%.

  9. Conceptual design and analysis of a Dish-Rankine solar thermal power system

    SciTech Connect

    Pons, R.L.

    1980-08-01

    A Point Focusing Distributed Receiver (PFDR) solar thermal electric system which employs small Organic Rankine Cycle (ORC) engines is examined with reference to its projected technical/economic performance. With mass-produced power modules (about 100,000 per year), the projected life-cycle energy cost for an optimized no-storage system is estimated at 67 mills/kWh (Levelized Busbar Energy Cost) without the need for advanced development of any of its components. At moderate production rates (about 50 MWe/yr) system energy costs are competitive with conventional power generation systems in special remote-site types of applications.

  10. Low-Power Maximum Power Point Tracker with Digital Control for Thermophotovoltaic Generators

    E-print Network

    Pilawa, Robert

    This paper describes the design, optimization, and evaluation of the power electronics circuitry for a low-power portable thermophotovotaic (TPV) generator system. TPV system is based on a silicon micro-reactor design and ...

  11. Self-powered wireless sensor system using MEMS piezoelectric micro power generator (PMPG)

    E-print Network

    Xia, YuXin, M.B.A. Sloan School of Management.

    2006-01-01

    A thin-film lead zirconate titanate, Pb(Zr,Ti)03, MEMS Piezoelectric Micro Power Generator (PMPG) has been integrated with a commercial wireless sensor node (Telos), to demonstrate a self-powered RF temperature sensor ...

  12. Protective, Modular Wave Power Generation System

    SciTech Connect

    Vvedensky, Jane M.; Park, Robert Y.

    2012-11-27

    The concept of small wave energy conversion modules that can be built into large, scalable arrays, in the same vein as solar panels, has been developed. This innovation lends itself to an organic business and development model, and enables the use of large-run manufacturing technology to reduce system costs. The first prototype module has been built to full-scale, and tested in a laboratory wave channel. The device has been shown to generate electricity and dissipate wave energy. Improvements need to be made to the electrical generator and a demonstration of an array of modules should be made in natural conditions.

  13. Safe Operation of Backup Power Generators

    E-print Network

    Smith, David

    2006-04-19

    requirements of the latest safety standards (UL 2034, IAS 6-96 or CSA 6.19.01). Test alarms frequently and replace dead batteries. David W. Smith, Extension Safety Program The Texas A&M University System Electrocution dangers Portable generators convert... the home. This could electrocute unsus- pecting utility workers and/or neighbors who might be servicing the electrical system. It also bypasses some of the built-in household circuit protection devices. ? If you must connect the generator to the main...

  14. Sensorless maximum power point tracking control in wind energy generation using permanent magnet synchronous generator

    Microsoft Academic Search

    N. Srighakollapu; P. S. Sensarma

    2008-01-01

    This paper proposes a control strategy for variable speed wind energy conversion system (WECS), incorporating maximum power point tracking (MPPT) algorithm, using direct driven permanent magnet synchronous generator (PMSG). The generator is operated in the speed control mode below the base speed by controlling the terminal voltage using three phase front-end active-rectifier feeding power to the DC bus. The voltage

  15. ePOWER Seminar AC solar cells: A new breed of PV power generation

    E-print Network

    Abolmaesumi, Purang

    ePOWER Seminar AC solar cells: A new breed of PV power generation Professor Faisal Khan Assistant will provide a guideline for solar cell designers to fabricate various discrete components in a power converter-junction solar cells. Prof. Khan is the founder of the Power Engineering and Automation Research Lab (PEARL

  16. Low head power generation with bulb turbines

    Microsoft Academic Search

    J. L. Carson; R. S. Samuelson

    1978-01-01

    It is shown that axial turbines, such as bulb systems, provide an efficient and economical means for supplying power at very low-head hydroelectric installations. Particularly for installations having net operating heads less than 60 feet, bulb turbines have significant advantages over vertical-shaft Kaplan turbines. These advantages include: lower machinery costs, construction savings, runner accessibility, reduced costs for civil engineering features,

  17. High power microwave generation with pulse compression

    Microsoft Academic Search

    A. W. Biggs

    1995-01-01

    Chirped pulse compression is achieved in transmit modes with wideband antennas, such as log periodic dipole arrays (LPDA), where the matched filters are the antennas. In this paper, a modulation technique is described which compresses ultra wideband (UWB) signals on conventional LPDAs. In transmit modes, high power microwaves (HPM) applications are found with wideband transmitting antennas, such as LPDA, where

  18. Simulating the Value of Concentrating Solar Power with Thermal Energy Storage in a Production Cost Model

    SciTech Connect

    Denholm, P.; Hummon, M.

    2012-11-01

    Concentrating solar power (CSP) deployed with thermal energy storage (TES) provides a dispatchable source of renewable energy. The value of CSP with TES, as with other potential generation resources, needs to be established using traditional utility planning tools. Production cost models, which simulate the operation of grid, are often used to estimate the operational value of different generation mixes. CSP with TES has historically had limited analysis in commercial production simulations. This document describes the implementation of CSP with TES in a commercial production cost model. It also describes the simulation of grid operations with CSP in a test system consisting of two balancing areas located primarily in Colorado.

  19. Solar parabolic dish thermal power systems - Technology and applications

    NASA Technical Reports Server (NTRS)

    Lucas, J. W.; Marriott, A. T.

    1979-01-01

    Activities of two projects at JPL in support of DOE's Small Power Systems Program are reported. These two projects are the Point-Focusing Distributed Receiver (PFDR) Technology Project and the Point-Focusing Thermal and Electric Applications (PFTEA) Project. The PFDR Technology Project's major activity is developing the technology of solar concentrators, receivers and power conversion subsystems suitable for parabolic dish or point-focusing distributed receiver power systems. Other PFDR activities include system integration and cost estimation under mass production, as well as the testing of the hardware. The PFTEA Project's first major activity is applications analysis, that is seeking ways to introduce PFDR systems into appropriate user sectors. The second activity is systems engineering and development wherein power plant systems are analyzed for specific applications. The third activity is the installation of a series of engineering experiments in various user environments to obtain actual operating experience

  20. Pressurized circulating fluidized-bed combustion for power generation

    SciTech Connect

    Weimer, R.F.

    1995-08-01

    Second-generation Pressurized Circulating Fluidized Bed Combustion (PCFBC) is the culmination of years of effort in the development of a new generation of power plants which can operate on lower-quality fuels with substantially improved efficiencies, meet environmental requirements, and provide a lower cost of electricity. Air Products was selected in the DOE Clean Coal Technology Round V program to build, own, and operate the first commercial power plant using second-generation PCFBC technology, to be located at an Air Products chemicals manufacturing facility in Calvert City, Kentucky. This paper describes the second-generation PCFBC concept and its critical technology components.