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1

Thermal energy storage considerations for solar-thermal power generation  

Microsoft Academic Search

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,

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

1976-01-01

2

Thermal generation operating cost variations with wind power integration  

Microsoft Academic Search

The fluctuations and forecasting errors of wind power require large amount of flexibility in power system operation. The flexibility is often provided by conventional thermal generating units. This paper focuses on the variations in operating cost caused by integration of an increasing amount of wind power in thermal generation system. A new chronological production simulation platform utilized for this analysis

Ning Zhang; Chongqing Kang; Daniel S. Kirschen; Weimin Xi; Junhui Huang; Qian Zhang

2011-01-01

3

Low-cost distributed solar-thermal-electric power generation  

E-print Network

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

Sanders, Seth

4

Device for thermal transfer and power generation  

DOEpatents

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.

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

2011-04-19

5

Thermal investigation of a micro-gap thermionic power generator  

NASA Astrophysics Data System (ADS)

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.

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

2014-08-01

6

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

E-print Network

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

Sanders, Seth

7

Design of AC auxiliary power distribution systems for large TVA thermal power generating plants  

Microsoft Academic Search

This paper discusses TVA's practices in the design of ac auxiliary power distribution systems of large thermal generating plants. Its scope is limited to the primary portions of the system, including the station service transformers which step down the main generator voltage or switchyard voltage, and the switchgear and buses which distribute power from the secondaries of these transformers. Single-line

G. R. Reed; D. R. Webster

1975-01-01

8

Solar thermal power generation. A bibliography with abstracts  

NASA Technical Reports Server (NTRS)

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.

1979-01-01

9

High-density thermoelectric power generation and nanoscale thermal metrology  

E-print Network

Thermoelectric power generation has been around for over 50 years but has seen very little large scale implementation due to the inherently low efficiencies and powers available from known materials. Recent material advances ...

Mayer, Peter (Peter Matthew), 1978-

2007-01-01

10

A thermally efficient micro-reactor for thermophotovoltaic power generation  

E-print Network

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 ...

Nielsen, Ole Mattis, 1977-

2006-01-01

11

Thermal energy storage for coal-fired power generation  

Microsoft Academic Search

This paper presents an engineering and economic evaluation of using thermal energy storage (TES) with coal-fired conventional and combined cycle power plants. In the first case, conventional pulverized coal combustion equipment was assumed to continuously operate to heat molten nitrate salt which was then stored in a tank. During intermediate-load demand periods, hot salt was withdrawn from storage and used

M. K. Drost; S. Somasundaram; D. R. Brown; Z. I. Antoniak

1990-01-01

12

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

Microsoft Academic Search

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

Tetsuya Funatsu; Hiroaki Natsume

2009-01-01

13

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

E-print Network

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

Wu, Mingshen

14

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

Microsoft Academic Search

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

Artin der Minassians

2007-01-01

15

Solar thermal electricity generation  

Microsoft Academic Search

This report presents the results of modeling the thermal performance and economic feasibility of large (utility scale) and small solar thermal power plants for electricity generation. A number of solar concepts for power systems applications have been investigated. Each concept has been analyzed over a range of plant power ratings from 1 MW(sub e) to 300 MW(sub e) and over

Khairy Ramadan Gasemagha

1993-01-01

16

Technical and economical evaluation of solar thermal power generation  

Microsoft Academic Search

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

Theocharis Tsoutsos; Vasilis Gekas; Katerina Marketaki

2003-01-01

17

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 ...

18

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

NASA Technical Reports Server (NTRS)

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.

Amos, D. J.

1977-01-01

19

Thermal analysis of a simple-cycle gas turbine in biogas power generation  

SciTech Connect

This paper investigates the technical feasibility of utilizing small simple-cycle gas turbines (25 kW to 125 kW) for biogas power generation through thermal analysis. A computer code, GTPower, was developed to evaluate the performance of small simple-cycle gas turbines specifically for biogas combustion. The 125 KW Solar Gas Turbine (Tital series) has been selected as the base case gas turbine for biogas combustion. After its design parameters and typical operating conditions were entered into GTPower for analysis, GTPower outputted expected values for the thermal efficiency and specific work. For a sensitivity analysis, the GTPower Model outputted the thermal efficiency and specific work. For a sensitivity analysis, the GTPower Model outputted the thermal efficiency and specific work profiles for various operating conditions encountered in biogas combustion. These results will assist future research projects in determining the type of combustion device most suitable for biogas power generation.

Yomogida, D.E. [California Energy Commission, Sacramento, CA (United States); Thinh, Ngo Dinh [California State Univ., Sacramento, CA (United States)

1995-09-01

20

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

NASA Astrophysics Data System (ADS)

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.

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

21

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

DOEpatents

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.

Bowman, Charles D. (Los Alamos, NM)

1992-01-01

22

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

DOEpatents

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.

Bowman, C.D.

1992-11-03

23

Thermal Analysis of Step 2 GPHS for Next Generation Radioisotope Power Source Missions  

NASA Astrophysics Data System (ADS)

The Step 2 General Purpose Heat Source (GPHS) is a slightly larger and more robust version of the heritage GPHS modules flown on previous Radioisotope Thermoelectric Generator (RTG) missions like Galileo, Ulysses, and Cassini. The Step 2 GPHS is to be used in future small radioisotope power sources, such as the Stirling Radioisotope Generator (SRG110) and the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). New features include an additional central web of Fine Weave Pierced Fabric (FWPF) graphite in the aeroshell between the two Graphite Impact Shells (GIS) to improve accidental reentry and impact survivability and an additional 0.1-inch of thickness to the aeroshell broad faces to improve ablation protection. This paper details the creation of the thermal model using Thermal Desktop and AutoCAD interfaces and provides comparisons of the model to results of previous thermal analysis models of the heritage GPHS. The results of the analysis show an anticipated decrease in total thermal gradient from the aeroshell to the iridium clads compared to the heritage results. In addition, the Step 2 thermal model is investigated under typical SRG110 boundary conditions, with cover gas and gravity environments included where applicable, to provide preliminary guidance for design of the generator. Results show that the temperatures of the components inside the GPHS remain within accepted design limits during all envisioned mission phases.

Pantano, David R.; Hill, Dennis H.

2005-02-01

24

Consideration of Thermoelectric Power Generation by Using Hot Spring Thermal Energy or Industrial Waste Heat  

NASA Astrophysics Data System (ADS)

Today, we face some significant environmental and energy problems such as global warming, urban heat island, and the precarious balance of world oil supply and demand. However, we have not yet found a satisfactory solution to these problems. Waste heat recovery is considered to be one of the best solutions because it can improve energy efficiency by converting heat exhausted from plants and machinery to electric power. This technology would also prevent atmospheric temperature increases caused by waste heat, and decrease fossil fuel consumption by recovering heat energy, thus also reducing CO2 emissions. The system proposed in this research generates electric power by providing waste heat or unharnessed thermal energy to built-in thermoelectric modules that can convert heat into electric power. Waste heat can be recovered from many places, including machinery in industrial plants, piping in electric power plants, waste incineration plants, and so on. Some natural heat sources such as hot springs and solar heat can also be used for this thermoelectric generation system. The generated power is expected to be supplied to auxiliary machinery around the heat source, stored as an emergency power supply, and so on. The attributes of this system are (1) direct power generation using hot springs or waste heat; (2) 24-h stable power generation; (3) stand-alone power system with no noise and no vibration; and (4) easy maintenance attributed to its simple structure with no moving parts. In order to maximize energy use efficiency, the temperature difference between both sides of the thermoelectric (TE) modules built into the system need to be kept as large as possible. This means it is important to reduce thermal resistance between TE modules and heat source. Moreover, the system's efficiency greatly depends on the base temperature of the heat sources and the material of the system's TE modules. Therefore, in order to make this system practical and efficient, it is necessary to choose the heat source first and then design the most appropriate structure for the source by applying analytical methods. This report describes how to design a prototype of a thermoelectric power generator using the analytical approach and the results of performance evaluation tests carried out in the field.

Sasaki, Keiichi; Horikawa, Daisuke; Goto, Koichi

2014-05-01

25

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

Microsoft Academic Search

The results obtained from combined thermal and chemical tests of the steam generator of Unit 3 at the Kalinin nuclear power\\u000a station are summarized. The obtained data are compared with the results of thermal and chemical tests carried out on steam\\u000a generators at other nuclear power stations equipped with VVER-1000 reactors, and recommendations on selecting the steam-generator\\u000a blowdown schedule are

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

2007-01-01

26

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

Microsoft Academic Search

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

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

2009-01-01

27

Research and development on a distributed type solar thermal power generation plant  

NASA Astrophysics Data System (ADS)

The R&D on a solar thermal power generation system of the plane parabolic type within the framework of the Japanese Sunshine Project is described. This system realizes high concentration of solar energy with a special concentrator module which combines 100 flat plate mirror heliostats of the central tower system with 5 parabolic troughs of the distributed system. A molten salt (KCl-LiCl) type thermal storage unit is used to superheat saturated steam supplied by accumulators to 300-350 C for 90 minutes after 5 hours of heat storage. Specifications and hydrodynamic characteristics for a 1000 kWe pilot plant in Nio, Kagawa, Japan, constructed in 1980 are given.

Sumida, I.; Tsukamoto, M.; Sakamoto, T.; Taki, T.; Sato, S.

1983-12-01

28

Novel Molten Salts Thermal Energy Storage for Concentrating Solar Power Generation  

SciTech Connect

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.

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

2013-10-23

29

Metal Hydride Thermal Storage: Reversible Metal Hydride Thermal Storage for High-Temperature Power Generation Systems  

SciTech Connect

HEATS Project: PNNL is developing a thermal energy storage system based on a Reversible Metal Hydride Thermochemical (RMHT) system, which uses metal hydride as a heat storage material. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. PNNL’s metal hydride material can reversibly store heat as hydrogen cycles in and out of the material. In a RHMT system, metal hydrides remain stable in high temperatures (600- 800°C). A high-temperature tank in PNNL’s storage system releases heat as hydrogen is absorbed, and a low-temperature tank stores the heat until it is needed. The low-cost material and simplicity of PNNL’s thermal energy storage system is expected to keep costs down. The system has the potential to significantly increase energy density.

None

2011-12-05

30

SENSITIVITY OF THERMAL POWER GENERATION TO CLIMATE G. P. Harrison*, L. C. Cradden, A. Zacheshigriva, S. Nairn, J. P. Chick  

E-print Network

of impacts on the electricity industry affecting generation, transmission and demand. One specific effect, for the CCGT plant which takes air temperature as input, three emissions scenarios of `low', `med' and `highSENSITIVITY OF THERMAL POWER GENERATION TO CLIMATE CHANGE G. P. Harrison*, L. C. Cradden, A

Harrison, Gareth

31

Development of a dual-medium thermal storage system for solar turbo-electric power generation  

Microsoft Academic Search

A thermal storage subsystem has been tested for a 10-MW solar electric power plant. A dual-medium concept, which relies on both solid material (e.g. rock, ore, metal, brick or ceramic) and a liquid (such as water, petroleum products, heat transfer fluids or molten salts) for thermal storage, was adopted for the subsystem. The upper temperature limit for the thermal storage

G. R. Morgan; G. R. Schneider; W. Unterberg

1978-01-01

32

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

Microsoft Academic Search

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

Brian Norton; Phillip C Eames; Steve NG Lo

1998-01-01

33

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

PubMed

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

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

2008-07-21

34

Solar Thermal Power.  

ERIC Educational Resources Information Center

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…

McDaniels, David K.

35

Solar thermal electricity generation  

NASA Astrophysics Data System (ADS)

This report presents the results of modeling the thermal performance and economic feasibility of large (utility scale) and small solar thermal power plants for electricity generation. A number of solar concepts for power systems applications have been investigated. Each concept has been analyzed over a range of plant power ratings from 1 MW(sub e) to 300 MW(sub e) and over a range of capacity factors from a no-storage case (capacity factor of about 0.25 to 0.30) up to intermediate load capacity factors in the range of 0.46 to 0.60. The solar plant's economic viability is investigated by examining the effect of various parameters on the plant costs (both capital and O & M) and the levelized energy costs (LEC). The cost components are reported in six categories: collectors, energy transport, energy storage, energy conversion, balance of plant, and indirect/contingency costs. Concentrator and receiver costs are included in the collector category. Thermal and electric energy transport costs are included in the energy transport category. Costs for the thermal or electric storage are included in the energy storage category; energy conversion costs are included in the energy conversion category. The balance of plant cost category comprises the structures, land, service facilities, power conditioning, instrumentation and controls, and spare part costs. The indirect/contingency category consists of the indirect construction and the contingency costs. The concepts included in the study are (1) molten salt cavity central receiver with salt storage (PFCR/R-C-Salt); (2) molten salt external central receiver with salt storage (PFCR/R-E-Salt); (3) sodium external central receiver with sodium storage (PFCR/RE-Na); (4) sodium external central receiver with salt storage (PFCR/R-E-Na/Salt); (5) water/steam external central receiver with oil/rock storage (PFCR/R-E-W/S); (6) parabolic dish with stirling engine conversion and lead acid battery storage (PFDR/SLAB); (7) parabolic dish with stirling engine conversion and redox advanced battery storage (PFDR/S-RAB); and (8) parabolic trough with oil/rock storage (LFDR/R-HT-45). Key annual efficiency and economic results of the study are highlighted in tabular format for plant sizes and capacity factor that resulted in the lowest LEC over the analysis range.

Gasemagha, Khairy Ramadan

1993-01-01

36

Power generation, operation, and control  

SciTech Connect

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. Economic Dispatch of Thermal Units and Methods of Solution. Transmission Losses. Unit Commitment. Generation with Limited Energy Supply. Hydrothermal Coordination. Energy Production Cost Models for Fuel Budgeting and Planning. Control of Generation. Interchange Evaluation and Power Pools. Power System Security. An introduction to State Estimation in Power Systems and Appendixes.

Wood, A.J.; Wollenberg, B.F.

1984-01-01

37

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

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

38

Concentrating solar thermal power.  

PubMed

In addition to wind and photovoltaic power, concentrating solar thermal power (CSP) will make a major contribution to electricity provision from renewable energies. Drawing on almost 30 years of operational experience in the multi-megawatt range, CSP is now a proven technology with a reliable cost and performance record. In conjunction with thermal energy storage, electricity can be provided according to demand. To date, solar thermal power plants with a total capacity of 1.3 GW are in operation worldwide, with an additional 2.3 GW under construction and 31.7 GW in advanced planning stage. Depending on the concentration factors, temperatures up to 1000°C can be reached to produce saturated or superheated steam for steam turbine cycles or compressed hot gas for gas turbine cycles. The heat rejected from these thermodynamic cycles can be used for sea water desalination, process heat and centralized provision of chilled water. While electricity generation from CSP plants is still more expensive than from wind turbines or photovoltaic panels, its independence from fluctuations and daily variation of wind speed and solar radiation provides it with a higher value. To become competitive with mid-load electricity from conventional power plants within the next 10-15 years, mass production of components, increased plant size and planning/operating experience will be accompanied by technological innovations. On 30 October 2009, a number of major industrial companies joined forces to establish the so-called DESERTEC Industry Initiative, which aims at providing by 2050 15 per cent of European electricity from renewable energy sources in North Africa, while at the same time securing energy, water, income and employment for this region. Solar thermal power plants are in the heart of this concept. PMID:23816910

Müller-Steinhagen, Hans

2013-08-13

39

Thermal energy storage for solar power generation - State of the art  

Microsoft Academic Search

High temperature storage for applications in solar-thermal electric systems is considered. Noting that thermal storage is in either the form of latent, sensible or chemically stored heat, sensible heat storage is stressed as the most developed of the thermal storage technologies, spanning direct heating of a storage medium from 120-1250 C. Current methods involve solids, packed beds, fluidized beds, liquids,

K. N. Shukla

1981-01-01

40

Examination of a Thermally Viable Structure for an Unconventional Uni-Leg Mg2Si Thermoelectric Power Generator  

NASA Astrophysics Data System (ADS)

We have fabricated an unconventional uni-leg structure thermoelectric generator (TEG) element using quad thermoelectric (TE) chips of Sb-doped n-Mg2Si, which were prepared by a plasma-activated sintering process. The power curve characteristics, the effect of aging up to 500 h, and the thermal gradients at several points on the module were investigated. The observed maximum output power with the heat source at 975 K and the heat sink at 345 K was 341 mW, from which the ? T for the TE chip was calculated to be about 333 K. In aging testing in air ambient, a remarkable feature of the results was that there was no notable change from the initial resistance of the TEG module for as long as 500 h. The thermal distribution for the fabricated uni-leg TEG element was analyzed by finite-element modeling using ANSYS software. To tune the calculation parameters of ANSYS, such as the thermal conductance properties of the corresponding coupled materials in the module, precise measurements of the temperature at various probe points on the module were made. Then, meticulous verification between the measured temperature values and the results calculated by ANSYS was carried out to optimize the parameters.

Sakamoto, Tatsuya; Iida, Tsutomu; Taguchi, Yutaka; Kurosaki, Shota; Hayatsu, Yusuke; Nishio, Keishi; Kogo, Yasuo; Takanashi, Yoshifumi

2012-06-01

41

Electrical power generating system  

NASA Astrophysics Data System (ADS)

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.

Nola, F. J.

1981-03-01

42

Fishbone-like internal kink instability driven by supra-thermal electrons on FTU generated by lower hybrid radiofrequency power  

E-print Network

EX/P8-12 Fishbone-like internal kink instability driven by supra-thermal electrons on FTU generated@frascati.enea.it Abstract. The fishbone-like internal kink instability driven by supra-thermal electrons generated by lower can be usefully modelled by the analogous effect induced by the fast electrons on the low frequency

Zonca, Fulvio

43

Innovative Application of Maintenance-Free Phase-Change Thermal Energy Storage for Dish-Engine Solar Power Generation  

SciTech Connect

This final report summarizes the final results of the Phase II Innovative Application of Maintenance-Free Phase-Change Thermal Energy Storage for Dish-Engine Solar Power Generation project being performed by Infinia Corporation for the U.S. Department of Energy under contract DE-FC36-08GO18157 during the project period of September 1, 2009 - August 30, 2012. The primary objective of this project is to demonstrate the practicality of integrating thermal energy storage (TES) modules, using a suitable thermal salt phase-change material (PCM) as its medium, with a dish/Stirling engine; enabling the system to operate during cloud transients and to provide dispatchable power for 4 to 6 hours after sunset. A laboratory prototype designed to provide 3 kW-h of net electrical output was constructed and tested at Infinia's Ogden Headquarters. In the course of the testing, it was determined that the system's heat pipe network - used to transfer incoming heat from the solar receiver to both the Stirling generator heater head and to the phase change salt - did not perform to expectations. The heat pipes had limited capacity to deliver sufficient heat energy to the generator and salt mass while in a charging mode, which was highly dependent on the orientation of the device (vertical versus horizontal). In addition, the TES system was only able to extract about 30 to 40% of the expected amount of energy from the phase change salt once it was fully molten. However, the use of heat pipes to transfer heat energy to and from a thermal energy storage medium is a key technical innovation, and the project team feels that the limitations of the current device could be greatly improved with further development. A detailed study of manufacturing costs using the prototype TES module as a basis indicates that meeting DOE LCOE goals with this hardware requires significant efforts. Improvement can be made by implementing aggressive cost-down initiatives in design and materials, improving system performance by boosting efficiencies, and by refining cost estimates with vendor quotes in lieu of mass-based approaches. Although the prototype did not fully demonstrate performance and realize projected cost targets, the project team believes that these challenges can be overcome. The test data showed that the performance can be significantly improved by refining the heat pipe designs. However, the project objective for phase 3 is to design and test on sun the field ready systems, the project team feels that is necessary to further refine the prototype heat pipe design in the current prototype TES system before move on to field test units, Phase 3 continuation will not be pursued.

Qui, Songgang [Temple University] [Temple University; Galbraith, Ross [Infinia] [Infinia

2013-01-23

44

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

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

45

MHD Power Generation  

ERIC Educational Resources Information Center

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)

Kantrowitz, Arthur; Rosa, Richard J.

1975-01-01

46

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

SciTech Connect

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.

R. Panneer Selvam, Micah Hale and Matt strasser

2013-03-31

47

Electrical power generating system  

NASA Astrophysics Data System (ADS)

A power generating system for adjusting coupling an induction motor, as a generator, to an A.C. power line wherein the motor and power line are connected through a triac is described. 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.

Nola, F. J.

1983-06-01

48

Electrical power generating system  

NASA Technical Reports Server (NTRS)

A power generating system for adjusting coupling an induction motor, as a generator, to an A.C. power line wherein the motor and power line are connected through a triac is described. 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.

Nola, F. J. (inventor)

1983-01-01

49

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

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

Andreas Poullikkas

2009-01-01

50

Electrical power generating system. [for windpowered generation  

NASA Technical Reports Server (NTRS)

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.

Nola, F. J. (inventor)

1981-01-01

51

Magnetohydrodynamic power generation  

NASA Technical Reports Server (NTRS)

Magnetohydrodynamic (MHD) Power Generation is a concise summary of MHD theory, history, and future trends. Results of the major international MHD research projects are discussed. Data from MHD research is included. Economics of initial and operating costs are considered.

Smith, J. L.

1984-01-01

52

Use of biogas for cogeneration of heat and electricity for local application: performance evaluation of an engine power generator and a sludge thermal dryer.  

PubMed

A small unit of cogeneration of energy and heat was tested at the Centre for Research and Training on Sanitation UFMG/COPASA - CePTS, located at the Arrudas Sewage Treatment Plant, in Belo Horizonte, Minas Gerais, Brazil. The unit consisted of an engine power generator adapted to run on biogas, a thermal dryer prototype and other peripherals (compressor, biogas storage tank, air blower, etc.). The heat from engine power generator exhaust gases was directed towards the thermal dryer prototype to dry the sludge and disinfect it. The results showed that the experimental apparatus is self-sufficient in electricity, even producing a surplus, available for other uses. The tests of drying and disinfection of sludge lasted 7 h, leading to an increase in solids content from 4 to 8% (50% reduction in sludge volume). Although the drying of sludge was not possible (only thickening was achieved), the disinfection process proved very effective, enabling the complete inactivation of helminth eggs. PMID:23128634

Lobato, L C S; Chernicharo, C A L; Pujatti, F J P; Martins, O M; Melo, G C B; Recio, A A R

2013-01-01

53

Thermal and dynamic analysis of the RING (Radiatively-cooled, Inertially-driven Nuclear Generator) power system radiator  

SciTech Connect

The nuclear option for a space-based power system appears most suitable for missions that require long-term, sustained operation at power levels above 100 kWe. Systems currently available operate at relatively low thermal efficiencies (6--10%). Thus, a 100 kWe system must discharge nearly 2 MWth of waste heat through the comparatively inefficient process of radiative cooling. The impact of the resultant radiator assembly size on overall power system weight is significant, and has led to proposals for radiators with potentially higher efficiencies. Examples include the: liquid droplet radiator; fabric radiator; bubble membrane radiator; rotating film radiator; and dust radiator. 14 refs., 2 figs., 2 tabs.

Apley, W.J.; Babb, A.L.

1989-01-01

54

Optimal Thermal Generating Unit Commitment  

Microsoft Academic Search

The paper describes a new method of scheduling thermal generating units to achieve minimum operating costs including both running and start-up costs while at the same time maintaining a desired level of system security.

A. K. AyoubandA; A. D. Patton

1971-01-01

55

Future trends in power generation cost by power resource  

NASA Astrophysics Data System (ADS)

The Japan Energy Economy Research Institute has been evaluating power generation cost by each power resource every year focusing on nuclear power generation. The Institute is surveying the cost evaluations by power resources in France, Britain and the U.S.A., the nuclear generation advanced nations. The OECD is making power generation cost estimation using a hypothesis which uniforms basically the conditions varying in different member countries. In model power generation cost calculations conducted by the Ministry of International Trade and Industry of Japan, nuclear power generation is the most economical system in any fiscal year. According to recent calculations performed by the Japan Energy Economy Research Institute, the situation is such that it is difficult to distinguish the economical one from others among the power generation systems in terms of generation costs except for thermal power generation. Economic evaluations are given on estimated power generation costs based on construction costs for nuclear and thermal power plants, nuclear fuel cycling cost, and fuel cost data on petroleum, LNG and coal. With regard to the future trends, scenario analyses are made on generation costs, that assume fluctuations in fuel prices and construction costs, the important factors to give economic influence on power generation.

1992-08-01

56

Generating a representative signal of coal ash content to anticipate combustion control in a thermal power station.  

PubMed

This paper describes the possibilities of continuously measuring coal ash in the boiler feeding circuit of a thermal power station so that the measurement can be used as a signal for the boiler combustion control system. An installation was designed, at semi-industrial scale, that could faithfully reproduce the operation of a belt feeder. In order to measure the ash content, a natural radioactivity meter was installed and a large number of coal samples with different ranks and grain sizes were tested, eventually showing the possibility of achieving the objective. PMID:15082052

Prieto-Fernández, Ismael; Santurio-Díaz, José M; Folgueras-Díaz, Belén; López-Bobo, M Rosario; Fernández-Viar, Pedro

2004-05-01

57

SOLAR THERMAL POWER PLANTS FOR HYDROGEN PRODUCTION  

Microsoft Academic Search

Renewable power plants are needed, if a high amount of hydrogen shall be produced for the use in a climate-compatible energy market. Since the potentials of hydro and wind power are limited, solar electricity generation will take over an important part in the near future. Solar thermal power plants in the Mediterranean area are one promising option. After a short

Volker Quaschning; Franz Trieb

2001-01-01

58

Thermal energy storage for power plant applications  

Microsoft Academic Search

This study was conducted by Pacific Northwest Laboratory (PNL) to evaluate alternative methods of using coal to generate peak and intermediate load power. The approach was to review the technical and economic feasibility of using thermal energy storage (TES) with a conventional coal-fired power plant and an integrated gasification combined cycle (IGCC) power plant. In the first case, conventional pulverized

S. Somasundaram; M. K. Drost; Z. I. Antoniak; D. R. Brown

1990-01-01

59

Peak power ratio generator  

DOEpatents

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.

Moyer, Robert D. (Albuquerque, NM)

1985-01-01

60

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

SciTech Connect

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.

Phillip Hutton; Nikhil Patel; Kyle Martin; Devinder Singh

2008-02-01

61

Thermal batteries for aircraft emergency power  

NASA Astrophysics Data System (ADS)

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.

Ryan, David M.

1993-02-01

62

Power generating system  

Microsoft Academic Search

A method and apparatus for generating energy are presented wherein fluid flowing from the base of a standpipe drives a power converter such as a turbine. The discharged fluid is recycled to the top of the standpipe by pumping chambers which are filled by the flowing fluid and then discharged by compressed air. The compressed air is derived from a

Gillilan

1978-01-01

63

Investing in Power Generation  

Microsoft Academic Search

\\u000a In light of considerable political and market risk emanating from energy market liberalization, global warming, and rapid\\u000a technological change, adequate investment in power generation capacity is of paramount importance for ensuring the security\\u000a of electricity supply and a smooth transition to a more decentralized, energy-efficient and renewable energy system. Consequently,\\u000a investors have to use more sophisticated approaches to determine optimal

Reinhard Madlener; Rik W. De Doncker

64

Spectrophotovoltaic orbital power generation  

NASA Technical Reports Server (NTRS)

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.

Onffroy, J. R.

1980-01-01

65

Microfabricated thermoelectric power-generation devices  

NASA Technical Reports Server (NTRS)

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.

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

66

Assessment of generic solar thermal systems for large power applications: Analysis of electric power generating costs for systems larger than 10 MWe, volume 1  

Microsoft Academic Search

Seven generic types of collectors, together with associated subsystems for electric power generation, were considered. The collectors can be classified into three categories: two-axis tracking (with compound-curvature reflecting surfaces); one-axis tracking (with single-curvature reflecting surfaces); and 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

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

1980-01-01

67

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...

68

Innovative technologies for full utilization of ash generated at coal-fired thermal power stations for producing alumina and construction materials  

NASA Astrophysics Data System (ADS)

The possibility of full 100% usage of ash from coal-fired thermal power stations for producing raw materials for the cement and alumina industries is considered, and it is shown that comprehensive processing of ash from coal-fired thermal power stations is required for this purpose.

Delitsyn, L. M.; Vlasov, A. S.; Borodina, T. I.; Ezhova, N. N.; Sudareva, S. V.

2013-04-01

69

Wave powered buoy generator  

SciTech Connect

The wave powered buoy generator includes a hollow buoy which has inner and outer surfaces. The buoy is preferably spherical in shape. One or more windings are mounted to the buoy parallel to its surfaces with each winding having a pair of ends. A magnetized device which, is preferably a ball, is located within the buoy for rolling back and forth therein. A device is connected to the ends of the windings for rectifying current flow therefrom. With this arrangement the buoy can be moored in a body of water, and, when there is water motion, the flux lines of the magnetized roller device cut the one or more windings so as to cause electrical current flow to be provided through the rectifying device.

Rowe, R.A.

1985-01-08

70

Wave powered buoy generator  

SciTech Connect

The wave powered buoy generator includes a hollow buoy which has inner and outer surfaces. The buoy is preferably spherical in shape. One or more windings are mounted to the buoy parallel to its surfaces with each winding havng a pair of ends. A magnetized device which, is preferably a ball, is located within the buoy for rolling back and forth therein. A device is connected to the ends of the windings for rectifying current flow therefrom. With this arrangement the buoy can be moored in a body of water, and, when there is water motion, the flux lines of the magnetized roller device cut the one or more windings so as to cause electrical current flow to be provided through the rectifying device.

Rowe, R.A.

1982-12-02

71

Thermal Power Plant Micro Module  

NSDL National Science Digital Library

This learning object discusses and provides animations of the basic processes and components in a thermal power plant. Cycle descriptions and animations include the Carnot cycle, the basic Rankine cycle, and advanced Rankine cycles with reheating and feedwater heating. In addition, a Rankine cycle calculator allows the user to vary several operating parameters and observe the effect on power output and cycle efficiency.

2009-11-05

72

C. A. La Electricidad de Caracas: Feasibility-study definitional report. Arreciffs Units 1 through 5 repowering project, electric power generation expansion Venezuela thermal power plant. Export trade information  

SciTech Connect

C.A. La Electricidad de Caracas (E.de C.) is a private company which in 1991 served some 830,000 customers in an area of 4,160 square kilometers surrounding Caracas. A program is underway by E.de C. for upgrading equipment and expanding the capacity of several of its existing generating facilities. The Arrecifes repowering project will involve the addition of about 330 MW of new natural gas fired gas turbine generators and heat recovery steam generators (HRSGs) to five existing thermal power units built 30 to 40 years ago which have steam turbine generator sets of 26 to 41 MW each. The existing steam boilers will be removed. The limited but seemingly sufficient space available is to be a primary focus of the feasibility study.

Not Available

1991-05-01

73

Second generation PFB for advanced power generation.  

National Technical Information Service (NTIS)

Research is being conducted under a United States Department of Energy (USDOE) contract to develop a new type of coal-fueled plant for electric power generation. This new type of plant-called an advanced or second-generation pressurized fluidized bed comb...

A. Robertson, J. Van Hook

1995-01-01

74

Dynamic power systems for power generation  

NASA Astrophysics Data System (ADS)

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.

English, R. E.

1984-04-01

75

Sixth Northwest Conservation and Electric Power Plan Appendix I: Generating Resources -Background  

E-print Network

..................................................................................... 38 Concentrating Solar Thermal Power PlantSixth Northwest Conservation and Electric Power Plan Appendix I: Generating Resources - Background ............................................................................... 26 Woody Residue Power Plants

76

Mesofluidic magnetohydrodynamic power generation  

E-print Network

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 ...

Fucetola, Jay J

2012-01-01

77

Power generation systems and methods  

NASA Technical Reports Server (NTRS)

A power generation system includes a plurality of submerged mechanical devices. Each device includes a pump that can be powered, in operation, by mechanical energy to output a pressurized output liquid flow in a conduit. Main output conduits are connected with the device conduits to combine pressurized output flows output from the submerged mechanical devices into a lower number of pressurized flows. These flows are delivered to a location remote of the submerged mechanical devices for power generation.

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

2011-01-01

78

Automotive power generation and control  

Microsoft Academic Search

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

David J. Perreault; Vahe Caliskan

2004-01-01

79

ELECTROHYDRODYNAMIC POWER GENERATION. EXPERIMENTAL STUDIES  

Microsoft Academic Search

A series of experiments was performed to establish the feasibility of ; generating electrical power by means of a generator based upon the principle of ; the Van de Graff generator, the primary difference being that the charge is ; transported in a moving gas rather than on a moving belt. The experiments were ; performed using a corona ionization

J. M. Smith; W. Fried

1962-01-01

80

High power microwave generator  

DOEpatents

A device (10) for producing high-powered and coherent microwaves is described. The device comprises an evacuated, cylindrical, and hollow real cathode (20) that is driven to inwardly field emit relativistic electrons. The electrons pass through an internally disposed cylindrical and substantially electron-transparent cylindrical anode (24), proceed toward a cylindrical electron collector electrode (26), and form a cylindrical virtual cathode (32). Microwaves are produced by spatial and temporal oscillations of the cylindrical virtual cathode (32), and by electrons that reflex back and forth between the cylindrical virtual cathode (32) and the cylindrical real cathode (20).

Minich, Roger W. (Patterson, CA)

1988-01-01

81

Thermal Via Allocation for 3-D ICs Considering Temporally and Spatially Variant Thermal Power  

Microsoft Academic Search

The existing 3-D thermal-via allocation methods are based on the steady-state thermal analysis and may lead to excessive number of thermal vias. This paper develops an accurate and efficient thermal-via allocation considering the temporally and spatially variant thermal-power. The transient temperature is calculated by macromodel with a one-time structured and parameterized model reduction, which also generates temperature sensitivity with respect

Hao Yu; Yiyu Shi; Lei He; Tanay Karnik

2008-01-01

82

Autonomous Underwater Vehicle Thermoelectric Power Generation  

NASA Astrophysics Data System (ADS)

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.

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

2013-07-01

83

Coal and Nuclear Power Generation  

Microsoft Academic Search

\\u000a Historically the first electric power plants delivering large quantities of electric energy were hydro-electric. In 1895,\\u000a Westinghouse built the first AC electric power generator in Niagara Falls by passing water flow from the Falls through a turbine\\u000a that induced electric currents in copper windings. General Electric built high-power grid lines that took the 1.1 MWe of electricity\\u000a to Buffalo, New

Jeff W. Eerkens

84

Radiofrequency power deposition utilizing thermal imaging.  

PubMed

Wavelength effects influence radiofrequency (RF) power deposition distributions and limit magnetic resonance (MR) medical applications at very high magnetic fields. The power depositions in spherical saline gel phantoms were deduced from proton resonance shift thermal maps at both 1.5 T and 3.0 T over a range of conductivities. Phase differences before and after RF heating were measured for both a quadrature head coil and a circular surface coil. A long echo time (TE) pulse sequence with a 3D phase unwrap algorithm provided increased thermal sensitivity. The measured thermal maps agreed with a model of eddy-current heating by circularly polarized oscillating RF fields in a conducting dielectric sphere. At 3.0 T, thermal maps were acquired with a <0.32 degrees C temperature rise at 4 W. Proton resonance shift thermal maps provided a measure of hot spots in very-high-field MR imaging (MRI), in which both the phase sensitivity and signal-to-noise ratio (SNR) were increased. The method provides a means of studying the heat distribution generated by RF coils excited by clinical pulse sequences. PMID:15170832

Cline, Harvey; Mallozzi, Richard; Li, Zhu; McKinnon, Graeme; Barber, William

2004-06-01

85

An Isotope-Powered Thermal Storage unit for space applications  

NASA Astrophysics Data System (ADS)

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.

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

86

Thermoelectric power generation in a thermoacoustic refrigerator  

Microsoft Academic Search

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

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

2006-01-01

87

Financing Solar Thermal Power Plants  

SciTech Connect

The commercialization of concentrating solar power technology took a major step forward in the mid 1980s and early 1990s with the development of the SEGS plants in California. Over the years they have proven that parabolic trough power technologies are the most cost-effective approach for commercial scale solar power generation in the sunbelt countries of the world. However, the question must be asked why no additional solar power plants have been build following the bankruptcy of the developer of the SEGS projects, LUZ International Limited. Although many believe the SEGS projects were a success as a result of parabolic trough technology they employ, in truth, the SEGS projects were developed simply because they represented an attractive opportunity for investors. Simply stated, no additional projects have been developed because no one has been able to put together a similarly attractive financial package to potential investors. More than $1.2 billion in private capital was raised i n debt and equity financing for the nine SEGS plants. Investors and bankers who make these investments are the real clients for solar power technologies. They are not interested in annual solar to electric efficiencies, but in risk, return on investments, and coverage ratios. This paper will take a look at solar power projects from the financier's perspective. The challenge in moving forward is to attract private investors, commercial lenders, and international development agencies and to find innovative solutions to the difficult issues that investment in the global power market poses for solar power technologies.

Price, H. W.; Kistner, R.

1999-11-01

88

Optimal working conditions for thermoelectric generators with realistic thermal coupling  

E-print Network

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...

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

2011-01-01

89

Kinetics of thermal donor generation in silicon  

NASA Technical Reports Server (NTRS)

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.

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

1984-01-01

90

Entropy generation method to quantify thermal comfort  

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

91

Heat generating compositions for thermal batteries  

NASA Astrophysics Data System (ADS)

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.

Sheptunov, V. N.

1991-03-01

92

PARABOLOIDAL DISH SOLAR CONCENTRATORS FOR MULTI-MEGAWATT POWER GENERATION  

Microsoft Academic Search

Large scale solar thermal electric power generation technology based on concentrator systems are recieving increasing attention, with a range of large systems around the world recently completed or under construction. The first prototype of The ANU 400m 2 \\

Keith Lovegrove; A Zawadski; J Coventy

93

Electromagnetic generators for power harvesting  

Microsoft Academic Search

The design of electromagnetic generators that can be integrated within shoe soles is described. In this way, parasitic energy expended by a person when walking can be tapped and used to power portable electronic equipment. Designs are based on discrete permanent magnets and copper wire coils, and it is intended to improve performance by applying micro-fabrication technologies. Detailed descriptions of

M. Duffy; D. Carroll

2004-01-01

94

Open cycle air turbine solar thermal power system  

Microsoft Academic Search

Solar electrical power generation using a heated air turbine in conjunction with a tower-mounted central receiver and heliostat field can be hybrid fossil fuel fired so as to avoid thermal storage problems. Using a regenerative gas turbine open cycle, no cooling system is required. It is shown that with a solar receiver concept allowing a fast thermal response to transient

E. Le Grives

1979-01-01

95

An open cycle turbine solar thermal power system  

Microsoft Academic Search

Solar electrical power generation using a heated air turbine in conjunction with a tower mounted central receiver and heliostat field was hybrid fossil fuel fired so as to avoid thermal storage problems. Using a regenerative gas turbine open cycle, no cooling system was required. It is shown that with a solar receiver concept allowing a fast thermal response to transient

E. Legrives

1979-01-01

96

GREENHOUSE GAS ANALYSIS OF SOLAR-THERMAL ELECTRICITY GENERATION  

Microsoft Academic Search

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

M. LENZEN

1999-01-01

97

Investigations for biogas operated MHD power generators  

SciTech Connect

Biogas is produced from the anaerobic fermentation of the organic matter containing cellulose, such as agricultural wastes, human wastes, animal wastes, etc. It contains methane (50-70%), carbon dioxide (30-50%), and very small amounts of hydrogen and hydrogen sulphide. Adequate quantities of raw material to generate biogas are normally available in rural areas, and therefore, there is a possibility that almost all the energy requirements of the rural sector may be fulfilled by biogas. Presently in the rural sector, biogas is used mainly to provide thermal energy (for cooking, etc.), and up to a limited extent, to meet the electrical energy requirements by running electrical generators with engines powered by a mixture of oil and biogas. In this paper, the authors propose a scheme in which biogas can be used to generate electricity more efficiently by using magnetohydrodynamic (MHD) power generators. Investigations have been carried out to make feasibility studies for biogas-operated open cycle MHD power generators. Composition, temperature and electrical conductivity of the seeded (with potassium) combustion products of biogas-air/oxygen systems have been analytically investigated for different percentages of CO/sub 2/ in biogas and at various combustor pressures for a seeding ratio of 1 percent by weight. The effect of preheating and enrichment of air on temperature and electrical conductivity of the seeded combustion plasmas has also been studied.

Dahiya, R.P.; Chand, A.; Sharma, S.C.

1983-12-01

98

Next Generation Geothermal Power Plants  

SciTech Connect

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

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

1995-09-01

99

Results from comprehensive thermal and chemical tests of steam generator No. 2 in unit 1 at the Volgodonsk Nuclear Power Station  

Microsoft Academic Search

We present the results from investigating the distribution of the concentrations of sodium and iron (II + III) in the water\\u000a volume of a steam generator and an analysis of their behavior in the course of blowdown operations carried out in accordance\\u000a with the existing maintenance procedure when the power unit is run with its reactor plant operating at a

V. I. Gorburov; Yu. F. Kutdyusov; I. O. Bud’kov; A. Yu. Petrov; A. G. Zhukov; N. B. Trunov

2006-01-01

100

Homopolar generator power supply system  

SciTech Connect

A high-energy, high-current homopolar generator pulsed power supply system that is compact and field portable. The power supply system includes a homopolar generator (HPG), an auxiliary supply and drive system, both mounted on a skid frame, and a control system coupled to the HPG and drive system. The homopolar generator has a split rotor with insulation between the halves and a recess in the periphery. A stator ring and field coil, for producing a magnetic field through which the rotor halves make two simultaneous voltage-generating passes, are disposed within the recess in the rotor. Air-actuated brush mechanisms inside and outside the recess contact surfaces of the rotor and collect discharge current. The auxiliary supply and drive system includes a motoring system comprising hydraulic motors for driving the HPG to speed, a bearing lubrication system, a generator for energizing the field coil, and a brush actuator air supply system, all of which are driven by a prime mover. The control system comprises a logic controller for executing a prescribed sequence of steps including turning on the prime mover, initiating motoring of the HPG, energizing the field coil, and initiating the discharge of electrical current.

Weldon, W. F.; Gully, J. H.

1985-10-01

101

Induction generator powered coaxial launchers  

NASA Astrophysics Data System (ADS)

A launcher design which avoids the need for switching and automatically excites only the windings in the vicinity of the projectile is presented. The energy store for the launcher consists of rotating induction machines. The excitation for the launcher is provided by an excitation winding on the projectile, which makes the projectile act like the rotor of a synchronous condenser. This combination of super-synchronous induction machines (the energy stores) and synchronous alternators (the projectile) is called an induction generator. The induction generator powered launcher concept is described, and scaling laws to assess the applicability of this technology for tactical and space launch applications are investigated.

Driga, M. D.; Nalty, K. E.

1991-01-01

102

A distributed power generation communication system  

Microsoft Academic Search

A distributed power generation system (DPGS) consists of a number of small-scale power generation sources (SSPGS) that provide electric power at a site closer to the user than the central power generation station. Small-scale power generation technologies currently available include wind turbines, fuel cells, micro gas\\/diesel turbines, small hydro generators and photovoltaic panels. Currently, most SSPGSs are locally controlled and

Julian Meng

2003-01-01

103

Clean power generation from coal  

SciTech Connect

The chapter gives an overview of power generation from coal, describing its environmental impacts, methods of cleaning coal before combustion, combustion methods, and post-combustion cleanup. It includes a section on carbon dioxide capture, storage and utilization. Physical, chemical and biological cleaning methods are covered. Coal conversion techniques covered are: pulverized coal combustion, fluidized-bed combustion, supercritical boilers, cyclone combustion, magnetohydrodynamics and gasification. 66 refs., 29 figs., 8 tabs.

Butler, J.W.; Basu, P. [Dalhousie University, Halifax, NS (Canada). Dept. of Mechanical Engineering

2007-09-15

104

Solid oxide fuel cell distributed power generation  

SciTech Connect

Fuel cells are electrochemical devices that oxidize fuel without combustion to convert directly the fuel`s chemical energy into electricity. The solid oxide fuel cell (SOFC) is distinguished from other fuel cell types by its all solid state structure and its high operating temperature (1,000 C). The Westinghouse tubular SOFC stack is process air cooled and has integrated thermally and hydraulically within its structure a natural gas reformer that requires no fuel combustion and no externally supplied water. In addition, since the SOFC stack delivers high temperature exhaust gas and can be operated at elevated pressure, it can supplant the combustor in a gas turbine generator set yielding a dry (no steam) combined cycle power system of unprecedented electrical generation efficiency (greater 70% ac/LHV). Most remarkably, analysis indicates that efficiencies of 60 percent can be achieved at power plant capacities as low as 250 kWe, and that the 70 percent efficiency level should be achievable at the two MW capacity level. This paper describes the individual SOFC, the stack, and the power generation system and its suitability for distributed generation.

Veyo, S.E.

1997-12-31

105

Reliability Evaluation of Electric Power Generation Systems with Solar Power  

E-print Network

Conventional power generators are fueled by natural gas, steam, or water flow. These generators can respond to fluctuating load by varying the fuel input that is done by a valve control. Renewable power generators such as wind or solar, however...

Samadi, Saeed

2013-11-08

106

Thermal power plant cooperation with wind turbines  

Microsoft Academic Search

The popularity of wind energy is increasing and that arises several technical problems like system stability and wind power reliability. Power companies have learned how to predict power consumption and therefore know how to plan power generation. Adding notable amount of wind power into the system requires a new approach to system stability. The idea of wind power is to

Ivo Palu; Heiki Tammoja; Rein Oidram

2008-01-01

107

Local control of reactive power by distributed photovoltaic generators  

SciTech Connect

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.

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

108

Windmill having thermal and electric power output  

SciTech Connect

A windmill is described which has thermal and electric power output and includes windmill blades rotatably mounted and connected to a speed increaser mechanism of gears and shafts and a centrifugal compressor connected to the windmill thru the speed increaser to be driven by virtue of the wind applied to the blades of the windmill itself. A directional control is connected to the windmill head to have the windmill blades face into the wind, as desired. The compressor is connected to an insulated heat storage tank which contains storage material, such as brick, and the compressor discharge velocity and pressure difference are converted to heat, and the compressor fluid is returned to the compressor thru a screen which protects the compressor, and there is a flow control which automatically compensates for changes in density of the circulated air or compressor fluid. Also, a gas turbine generator can be connected with the compressor to be driven thereby, and electric elements could be connected with the generator for producing electricity. Two other embodiments show an impeller type of air brake and a valve and a heat-sensitive control, for generating heat or power.

Kenney, C.E.

1980-11-25

109

PARABOLOIDAL DISH SOLAR CONCENTRATORS FOR MULTI-MEGAWATT POWER GENERATION  

Microsoft Academic Search

Solar Thermal research and development began at the Australian National University in 1971. A prototype 400m2 solar dish was completed in 1994. The focus of the R&D efforts remains on the development of distributed dish, central generation solar thermal power systems using either direct steam generation or ammonia based thermochemical energy storage. Current work includes the re-commissioning of the 400m2

Keith Lovegrove; Tui Taumoefolau; Sawat Paitoonsurikarn; Piya Siangsukone; Greg Burgess; Andreas Luzzi; Glen Johnston; Olav Becker; Wie Joe

110

Power Generation: The Next 30 Years  

ERIC Educational Resources Information Center

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)

Holcomb, Robert W.

1970-01-01

111

A COMBUSTION-BASED MEMS THERMOELECTRIC POWER GENERATOR  

Microsoft Academic Search

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

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

2001-01-01

112

Thermally Isolated MEMS Thermo Converter for RF Power Sensor  

Microsoft Academic Search

This report discusses the design of Thermo-mechanical converter that creates heart of the RF power sensor microsystem. The conception of absorbed power measurement is based on thermal conversion, where absorbed RF power is transformed into thermal power, inside a thermally isolated system. Micromechanical Thermal Converter (MTC) spatial temperature dependences, thermal time constant and power to temperature characteristics are calculated from

JIRI JAKOVE NKO; MIROSLAV HUSAK; TIBOR LALINSKY

113

Electronic load for testing power generating devices  

NASA Technical Reports Server (NTRS)

Instrument tests various electric power generating devices by connecting the devices to the input of the load and comparing their outputs with a reference voltage. The load automatically adjusts until voltage output of the power generating device matches the reference.

Friedman, E. B.; Stepfer, G.

1968-01-01

114

Solar thermal power today and tomorrow  

Microsoft Academic Search

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.

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

1994-01-01

115

FUTURE POWER GRID INITIATIVE Next Generation Network  

E-print Network

FUTURE POWER GRID INITIATIVE Next Generation Network Simulations for Power System Applications communications directly into a power domain solver. Simulating a large scale power and communications network infrastructure for data communication networks to be used for power transmission and distribution power grids

116

Cascading Closed Loop Cycle Power Generation  

E-print Network

the combustion of fossil fuels. The WOWGen® power plant inherently reduces emissions and Greenhouse Gases (GHG) by producing power from waste heat without consuming fuel, thus increasing the overall energy efficiency of any industrial plant or power generation...

Romero, M.

2008-01-01

117

Water resource and power generation  

Microsoft Academic Search

We propose a simple model of competition between a thermal station and a hydrostation for the production of energy. We show that, despite the static characteristics of the thermal cost function, the thermal output is determined by intertemporal considerations. This results from the scarcity of the water resource which is storable at zero operating cost. We analyze the combination of

Claude Crampes; Michel Moreaux

2001-01-01

118

Low cost space power generation  

NASA Technical Reports Server (NTRS)

The success of this study has given a method of fabricating durable copolymer films without size limitations. Previously, only compression molded samples were durable enough to generate electrical energy. The strengthened specimens are very long lived materials. The lifetime was enhanced at least a factor of 1,300 in full pyroelectric conversion cycle experiments compared with extruded, non-strengthened film. The new techniques proved so successful that the lifetime of the resultant copolymer samples was not fully characterized. The lifetime of these new materials is so long that accelerated tests were devised to probe their durability. After a total of more than 67 million high voltage electrical cycles at 100 C, the electrical properties of a copolymer sample remained stable. The test was terminated without any detectable degradation to allow for other experiments. One must be cautious in extrapolating to power cycle performance, but 67 million electrical cycles correspond to 2 years of pyroelectric cycling at 1 Hz. In another series of experiments at reduced temperature and electrical stress, a specimen survived over one-third of a billion electrical cycles during nearly three months of continuous testing. The radiation-limited lifetimes of the copolymer were shown to range from several years to millions of years for most earth orbits. Thus, the pyroelectric copolymer has become a strong candidate for serious consideration for future spacecraft power supplies.

Olsen, Randall B.

1991-01-01

119

Storage systems for solar thermal power  

NASA Technical Reports Server (NTRS)

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.

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

1978-01-01

120

Equilibrium and kinetic studies of in situ generation of ammonia from urea in a batch reactor for flue gas conditioning of thermal power plants  

SciTech Connect

Ammonia has long been known to be useful in the treatment of flue/tail/stack gases from industrial furnaces, incinerators, and electric power generation industries. In this study, urea hydrolysis for production of ammonia, in different application areas that require safe use of ammonia at in situ condition, was investigated in a batch reactor. The equilibrium and kinetic study of urea hydrolysis was done in a batch reactor at reaction pressure to investigate the effect of reaction temperature, initial feed concentration, and time on ammonia production. This study reveals that conversion increases exponentially with an increase in temperature but with increases in initial feed concentration of urea the conversion decreases marginally. Further, the effect of time on conversion has also been studied; it was found that conversion increases with increase in time. Using collision theory, the temperature dependency of forward rate constant developed from which activation energy of the reaction and the frequency factor has been calculated. The activation energy and frequency factor of urea hydrolysis reaction at atmospheric pressure was found to be 73.6 kJ/mol and 2.89 x 10{sup 7} min{sup -1}, respectively.

Sahu, J.N.; Patwardhan, A.V.; Meikap, B.C. [Indian Institute of Technology, Kharagpur (India). Dept. of Chemical Engineering

2009-03-15

121

Transient Thermal Response Measurements of Power Transistors  

Microsoft Academic Search

Differences between the measured thermal impedance of power transistors when determined by the pulsed heating curve and cooling curve techniques are discussed. These differences are shown to result primarily because the power density distributions of these devices change as devicesheat; as a result of these changes the heating curve and the cooling curve are not conjugate. It is shown that

David L. Blackburn; Frank F. Oettinger

1975-01-01

122

Electronic power generators for ultrasonic frequencies  

NASA Technical Reports Server (NTRS)

The design and construction of an ultrasonic frequency electronic power generator are discussed. The principle design elements of the generator are illustrated. The generator provides an inductive load with an output power of two kilowatts and a variable output frequency in the fifteen to thirty KiloHertz range. The method of conducting the tests and the results obtained with selected materials are analyzed.

Ciovica, D.

1974-01-01

123

Electrical power generation by mechanically modulating electrical double layers.  

PubMed

Since Michael Faraday and Joseph Henry made their great discovery of electromagnetic induction, there have been continuous developments in electrical power generation. Most people today get electricity from thermal, hydroelectric, or nuclear power generation systems, which use this electromagnetic induction phenomenon. Here we propose a new method for electrical power generation, without using electromagnetic induction, by mechanically modulating the electrical double layers at the interfacial areas of a water bridge between two conducting plates. We find that when the height of the water bridge is mechanically modulated, the electrical double layer capacitors formed on the two interfacial areas are continuously charged and discharged at different phases from each other, thus generating an AC electric current across the plates. We use a resistor-capacitor circuit model to explain the results of this experiment. This observation could be useful for constructing a micro-fluidic power generation system in the near future. PMID:23403587

Moon, Jong Kyun; Jeong, Jaeki; Lee, Dongyun; Pak, Hyuk Kyu

2013-01-01

124

Thermal Performance of Wind Turbine Power System's Engine Room  

NASA Astrophysics Data System (ADS)

Greatly expanded use of wind energy has been proposed to reduce dependence on fossil and nuclear fuels for electricity generation. For wind turbine power generation, as a mature technology in the field of wind power utilization, its large-scale deployment is limited by the cooling technology. Therefore, the temperature distribution of the wind turbine power generation is a key issue for the design of the cooling system. It is because the characteristics of cooling system have a great effect on the performance of the wind turbine power generation. Based on some assumptions and simplifications, a thermal model is developed to describe the heat transfer behavior of wind turbine power system. The numerical calculation method is adopted to solve the governing equation. The heat generation and heat flux are investigated with a given operating boundary. The achieved results can be used to verify whether the cooling system meets the design requirements. Meanwhile, they also can reveal that among the influencing factors, the meteorological conditions, generated output and operation state as well seriously influence its thermal performance. Numerical calculation of the cooling system enables better understanding and results in performance improvement of the system.

Liu, Zhili; Jiang, Yanlong; Zhou, Nianyong; Shi, Hong; Kang, Na; Wang, Yu

125

Environment Friendly Coal Based Power Generation in Pakistan  

NASA Astrophysics Data System (ADS)

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.

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

2010-06-01

126

Identifying and bounding uncertainties in nuclear reactor thermal power calculations  

SciTech Connect

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)

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

2012-07-01

127

Space Station Freedom solar dynamic power generation  

NASA Technical Reports Server (NTRS)

Viewgraphs on Space Station Freedom solar dynamic power generation are presented. Topics covered include: prime contract activity; key solar dynamic power module requirements; solar dynamic heat receiver technology; and solar concentrator advanced development.

Springer, T.; Friefeld, Jerry M.

1990-01-01

128

Waste Heat Recovery Power Generation with WOWGen  

E-print Network

(pipeline compression stations, processing plants). Sources such as stack flue gases, steam, diesel exhaust, hot oil or combinations of sources can be used to generate power. WOWGen® can also be used with stand alone power plants burning fossil fuels...

Romero, M.

129

Pulse power applications of flux compression generators  

SciTech Connect

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.

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

1981-01-01

130

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

NASA Technical Reports Server (NTRS)

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

Marriott, A.

1980-01-01

131

High-power microwave pulse generator  

Microsoft Academic Search

An inexpensive alternative to commercial high-power microwave pulse generators is described. The present high-power microwave pulse generator utilizes a surplus MIT model 3 Mark II hard tube modulator and 2J51 magnetron. The basic design and technical details of the pulse generator are presented. The pulse generator is designed to produce 8.5–9.6 GHz pulses with pulse lengths ranging from 2 to

G. O. White; L. Chen; C. E. Patton; R. L. Tinkoff

1992-01-01

132

High-power microwave pulse generator  

Microsoft Academic Search

An inexpensive alternative to commercial high-power microwave-pulse generators is described. The present high-power microwave-pulse generator utilizes a surplus MIT model-3 Mark-II hard-tube modulator and 2J51 magnetron. The basic design and technical details of the pulse generator are presented. The pulse generator is designed to produce 8.5-9.6 GHz pulses with pulse lengths ranging from 2 to 4 microns with a nominal

G. O. White; L. Chen; C. E. Patton; R. L. Tinkoff

1992-01-01

133

High average power generation in barium nitrate Raman laser  

NASA Astrophysics Data System (ADS)

The generation of low divergent ( M 2?1.5) first and third Stokes radiation in a barium nitrate Raman laser with average powers of 11 W and 5 W, respectively, was demonstrated. The quantum conversion efficiency was up to 21%. The possibility of thermal lens compensation in such Raman lasers was shown.

Lisinetskii, V. A.; Riesbeck, T.; Rhee, H.; Eichler, H. J.; Orlovich, V. A.

2010-04-01

134

A dish-Stirling solar-thermal power system  

NASA Technical Reports Server (NTRS)

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.

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

1980-01-01

135

Small solar thermal electric power plants with early commercial potential  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

136

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

Microsoft Academic Search

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

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

2006-01-01

137

Symbiotic coupling of wind power and nuclear power generation  

Microsoft Academic Search

The coupling of wind power production as an intermittent supply to nuclear power generation as a base load supply is discussed. Wind turbines on a standby operational mode are net importers of power for their control and yaw mechanisms. They need a supply of about 5 kW of power from an existing grid. They also require the vicinity of a

Kate Rogers; Magdi Ragheb

2010-01-01

138

Electrical Power Generation Using Piezoelectric Crystal  

E-print Network

Abstract- The usefulness of most high technology devices such as cell phones, computers, and sensors is limited by the storage capacity of batteries. In the future, these limitations will become more pronounced as the demand for wireless power outpaces battery development which is already nearly optimized. Thus, new power generation techniques are required for the next generation of wearable computers, wireless sensors, and autonomous systems to be feasible. Piezoelectric materials are excellent power generation devices because of their ability to couple mechanical and electrical properties. For example, when an electric field is applied to piezoelectric a strain is generated and the material is deformed. Consequently, when a piezoelectric is strained it produces an electric field; therefore, piezoelectric materials can convert ambient vibration into electrical power. Piezoelectric materials have long been used as sensors and actuators; however their use as electrical generators is less established. A piezoelectric power generator has great potential for some remote applications such as in vivo sensors, embedded MEMS devices, and distributed networking. Developing piezoelectric generators is challenging because of their poor source characteristics (high voltage, low current, high impedance) and relatively low power output. This paper presents a theoretical analysis to increase the piezoelectric power generation that is verified with experimental results. Index Terms-Piezoelectric materials, piezoelectricity, power generation, PZT ceramics.

unknown authors

139

Small spacecraft power and thermal subsystems  

NASA Technical Reports Server (NTRS)

This white paper provides a general guide to the conceptual design of satellite power and thermal control subsystems with special emphasis on the unique design aspects associated with small satellites. The operating principles of these technologies are explained and performance characteristics of current and projected components are provided. A tutorial is presented on the design process for both power and thermal subsystems, with emphasis on unique issues relevant to small satellites. The ability of existing technology to meet future performance requirements is discussed. Conclusions and observations are presented that stress cost-effective, high-performance design solutions.

Eakman, D.; Lambeck, R.; Mackowski, M.; Slifer, L., Jr.

1994-01-01

140

Thermal storage requirements for parabolic dish solar power plants  

NASA Technical Reports Server (NTRS)

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.

Wen, L.; Steele, H.

1980-01-01

141

Pneumatic tire-based piezoelectric power generation  

NASA Astrophysics Data System (ADS)

Plug-in Hybrid Electric Vehicles (PHEVs) and Extended Range Electric Vehicles (EREVs) currently mainly rely on Internal Combustion Engines (ICE) utilizing conventional fuels to recharge batteries in order to extend their range. Even though Piezo-based power generation devices have surfaced in recent years harvesting vibration energy, their output has only been sufficient to power up sensors and other such smaller devices. The permanent need for a cleaner power generation technique still remains. This paper investigates the possibility of using piezoceramics for power generation within the vehicle's wheel assembly by exploiting the rotational motion of the wheel and the continuously variable contact point between the pneumatic tire and the road.

Makki, Noaman; Pop-Iliev, Remon

2011-03-01

142

The generative powers of demolition  

E-print Network

When examining the factory within the urban fabric, especially those cases that are abandoned and considered obsolete, it may be possible to see the first generative act as one of un-building. Considering demolition as an ...

Muskopf, Christopher Jon Dalton, 1975-

2005-01-01

143

Participatory Learning in Power Transformers Thermal Modeling  

Microsoft Academic Search

In this paper, we introduce a new approach based on the participatory learning paradigm to train a class of hybrid neurofuzzy networks whose aim is to model the thermal behavior of power transformers. The participatory learning paradigm is a training procedure that tends to emulate the human learning mechanism. An acceptance mechanism determines which observation is used for learning based

Michel Hell; P. Costa; F. Gomide

2008-01-01

144

Review of Microscale Magnetic Power Generation  

Microsoft Academic Search

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

David P. Arnold

2007-01-01

145

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

NASA Technical Reports Server (NTRS)

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.

1979-01-01

146

Power electronics as efficient interface in dispersed power generation systems  

Microsoft Academic Search

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,

Frede Blaabjerg; Zhe Chen; S. B. Kjaer

2004-01-01

147

The SAS-3 power and thermal systems  

NASA Technical Reports Server (NTRS)

Solar array configurations of the SAS-3 are described: a configuration with two sets of coplanar panels in the horizontal and two others in the vertical position, and two other configurations with either four horizontal or four vertical sets of panels. The nickel-cadmium battery of the power subsystem is described in detail, with emphasis on voltage limits and charge-discharge characteristics. The characteristic of 'solar-only' operation in the case of damage to the battery is discussed. The thermal subsystem of SAS-3 is considered, with discussions of thermal design criteria and the thermal environment. Temperature is controlled by using internal thermal louvers that regulate the rate at which the heat load from electronic equipment is transmitted to the outer surface for dumping to space.

Sullivan, R. M.; Hogrefe, A. F.; Brenza, P. T.

1975-01-01

148

A reagentless technology to prevent biofouling on the surfaces of equipment at nuclear and thermal power stations using generators of OH radicals and ozone  

NASA Astrophysics Data System (ADS)

We present the results obtained from the development and tests of a reagentless method to prevent biofouling in water cooling systems of equipment using generators of OH radicals and ozone constructed on the basis of impulse ultraviolet xenon lamps producing light with a wavelength of 172 nm.

Izyumov, S. V.; Shchekotov, E. Yu.; Shchekotov, D. E.; Krutskikh, D. A.

2011-07-01

149

Solar Thermal Power Plants with Parabolic-Trough Collectors  

NASA Astrophysics Data System (ADS)

Parabolic-trough collectors (PTC) are solar concentrating devices suitable to work in the 150°C- 400°C temperature range. Power plants based on this type of solar collectors are a very efficient way to produce electricity with solar energy. At present, there are eight commercial solar plants (called SEGS-II, III,.. IX) producing electricity with parabolic-trough collectors and their total output power is 340 MW. Though all SEGS plants currently in operation use thermal oil as a heat transfer fluid between the solar field and the power block, direct steam generation (DSG) in the receiver tubes is a promising option to reduce the cost of electricity produced with parabolic- trough power plants. Most of technical uncertainties associated to the DSG technology were studied and solved in the DISS project and it is expected that this new technology will be commercially available in a short term. In Spain, the Royal Decree No. 436/204 (March 12th , 2004) has defined a premium of 0,18€/kWh for the electricity produced by solar thermal power plants, thus promoting the installation of solar thermal power plants up to a limit of 200 MW. Due to the current legal and financial framework defined in Spain, several projects to install commercial solar power plants with parabolic-trough collectors are currently underway.

Zarza, E.; Valenzuela, L.; León, J.

2004-12-01

150

The thermal stability of photoacid generators in phenolic matrices  

SciTech Connect

The thermal stability of various photolabile sulfonate esters in phenolic matrices have been investigated by differential scanning calorimetry and thermogravimetric analysis. It was observed that the thermal stability of these photoacid generators is lowered in the presence of phenolic groups. As a result acid can be thermally generated, thereby reducing the selectivity of photoacid generation. The sulfonate esters investigated in phenolic matrices included nitrobenzyl tosylates, imino sulfonates, benzoin tosylate and 1,2,3-tris(methanesulfonyloxy)benzene. Also the effect of the thermal generation of acid from these photoacid generators on the temperature and rate of deprotection of partially t-butoxycarbonate blocked poly (vinylphenol) was studied by thermogravimetric analysis and FTIR.

Barclay, G.G.; Medeiros, D.R.; Sinta, R.F. [Shipley Co. Inc., Marlboro, MA (United States)

1993-12-31

151

Solar thermal power systems. Summary report  

SciTech Connect

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.

Not Available

1980-06-01

152

Real power measurement using a thermal converter  

NASA Astrophysics Data System (ADS)

In this paper, a new application of thermal converters is presented which allows energy, power and rms measurement without the need to substitute the measurement signal with a dc signal as performed in ac-dc transfer. Using a mathematical model of standard planar multijunction thermal converters (PMJTCs), the effective power acting inside the heater of the PMJTC is calculated from the output signal of its thermocouples. Due to the underlying physical principles, this method not only allows the calculation of the rms value of sinusoidal signals but also the average power and absolute energy contained in non-sinusoidal, non-periodic and even non-stationary signals, as appearing in the characterization of energy harvesters.

Möhring, Tobias; Spiegel, Thomas; Funck, Torsten

2014-03-01

153

PROBLEMS OF NUCLEAR POWER GENERATION  

Microsoft Academic Search

Utilization of nuclear energy is becoming economical even in the USSR ; which possesses sufficient coal and oil reserves for about 4 centuries; the ; problem is of special importance in countries which already must import their ; fuel supply. Development of reliable methods is more important than economic ; considerations. Calculations indicate that as the number of nuclear power

Aleksandrov

1962-01-01

154

Nuclear power: the next generation  

Microsoft Academic Search

There is a growing consensus within the nuclear power industry that reactors will have to be simpler, less costly, and safe beyond a doubt if they are to become attractive again. The major vendors are pursuing new, more efficient, and highly standardized reactor designs that are variants of present-day reactors built to meet the strict safety standards in an economical

Besmann

1984-01-01

155

An Implanted, Stimulated Muscle Powered Piezoelectric Generator  

NASA Technical Reports Server (NTRS)

A totally implantable piezoelectric generator system able to harness power from electrically activated muscle could be used to augment the power systems of implanted medical devices, such as neural prostheses, by reducing the number of battery replacement surgeries or by allowing periods of untethered functionality. The features of our generator design are no moving parts and the use of a portion of the generated power for system operation and regulation. A software model of the system has been developed and simulations have been performed to predict the output power as the system parameters were varied within their constraints. Mechanical forces that mimic muscle forces have been experimentally applied to a piezoelectric generator to verify the accuracy of the simulations and to explore losses due to mechanical coupling. Depending on the selection of system parameters, software simulations predict that this generator concept can generate up to approximately 700 W of power, which is greater than the power necessary to drive the generator, conservatively estimated to be 50 W. These results suggest that this concept has the potential to be an implantable, self-replenishing power source and further investigation is underway.

Lewandowski, Beth; Gustafson, Kenneth; Kilgore, Kevin

2007-01-01

156

Compliance strategy in national thermal power corporation, India  

SciTech Connect

Established in the mid-seventies the National Thermal Power Corporation (NTPC) is now the largest power producing company in India with an installed capacity of more than 16,000 MW. The environmental impacts associated with thermal power generation are inviting greater attention in the country. Power generation, a vital input for industrial development has to grow but at the same time emphasis on mitigation of environmental impact associated with thermal power generation can not be undermined. The Regulatory Agencies in the country are also enacting several environmental laws progressively to ensure that the industrial development is sustainable. The growing concern of Regulatory Agencies is evident from the Environmental Clearance accorded by them for power plants. As against simple conditions stipulated in clearances for projects in the late seventies the current regulatory clearances address specific protective actions in almost all areas of environment like air, water, noise, ecology etc. Compliance by utilities to environmental laws and requirements of the Regulatory Agencies is a major step toward sustainable development. At the NTPC Stations apart from compliance there is emphasis on data generation through scientific studies on different aspects of ecosystem where information are scanty or ground truth is to be established, adoption of eco-friendly measures like re-use and recycling where feasible for optimization of requirement of plant, schemes for treatments of effluents etc. to ensure enhanced performance and adoption of comprehensive environmental management program with a view to identify critical parameters and take timely corrective action. The paper underscores the concern of NTPC toward environmental protection. Compliance strategies vis a vis the environmental laws and requirements of Regulatory Agencies have been discussed.

Basu, B.; Rao, M.H.

1998-07-01

157

New low cost IGCC designs for competitive power generation  

SciTech Connect

Design studies of coal based 450 MW new IGCC power plants reveal their ability to compete in today's power generation market. Single train unit designs coupled with significant improvements in IGCC net output and efficiency have brought down the installed costs to the range of 850--1,000 $/kW and net thermal efficiency up to 43--47%. These improvements are shown to result from IGCC design configurations integrating new generation gas turbine combined cycles with High Pressure Texaco Gasification Technology and Elevated Pressure Air Separation Units.

Brdar, D.R.; Depuy, R.A.; Gulko, G.; Jandrisevits, M.; Paolino, J.

1999-07-01

158

Proceedings of the Fifth Parabolic Dish Solar Thermal Power Program  

NASA Technical Reports Server (NTRS)

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 with associated hardware and test results; distributed systems operating experience; international parabolic dish development activities; and non-DOE-sponsored domestic dish activities. Solar electric generation was also addressed.

Lucas, J. W. (editor)

1984-01-01

159

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

SciTech Connect

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

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

1998-07-01

160

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

Microsoft Academic Search

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

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

2009-01-01

161

Electrical machines technology for aerospace power generators  

NASA Astrophysics Data System (ADS)

Electric power generators for aerospace and aircraft applications are now required to be more reliable. It is noted that the wound field synchronous generator has been the workhorse for producing 400-Hz AC electric power for many years. Substantial evolution has occurred over the years by replacing low-speed generators with the 24,000-rpm design. The quality of the AC waveform produced by the wound field generators is excellent, the excitation power requirement is low, and control of output power is easily accomplished under abnormal operating conditions. Other changing requirements include variety of power types, increased reliability, and higher speeds and temperatures. It is pointed out that wound field synchronous generators have limitations due to rotating windings and rotating rectifiers. Other options such as self-regulating permanent magnet generators, switched reluctance generators, reluctance generators, flux switches overcome these limitations. It is suggested that the selection from these options must be based on the specific requirements for a given application, evaluating overall system constraints such as weight, performance, and cost.

Vaidya, Jayant G.

162

Solar thermoelectrics for small scale power generation  

E-print Network

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 ...

Amatya, Reja

2012-01-01

163

Analysis of power generation processes using petcoke  

E-print Network

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...

Jayakumar, Ramkumar

2009-05-15

164

Hybrid solar-fossil fuel power generation  

E-print Network

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 ...

Sheu, Elysia J. (Elysia Ja-Zeng)

2012-01-01

165

Selection and Evaluation of Thermal Interface Materials for Reduction of the Thermal Contact Resistance of Thermoelectric Generators  

NASA Astrophysics Data System (ADS)

A variety of thermal interface materials (TIMs) were investigated to find a suitable TIM for improving the performance of thermoelectric power generators (TEGs) operating in the medium-temperature range (600-900 K). The thermal resistance at the thermal interface between which the TIM was inserted was evaluated. The TIMs were chosen on the basis of their thermal stability when used with TEGs operating at medium temperatures, their electrical insulating properties, their thermal conductivity, and their thickness. The results suggest that the boron nitride (BN)-based ceramic coating, Whity Paint, and the polyurethane-based sheet, TSU700-H, are suitable TIMs for the heat source and heat sink sides, respectively, of the TEG. Use of these effectively enhances TEG performance because they reduce the thermal contact resistance at the thermal interface.

Sakamoto, Tatsuya; Iida, Tsutomu; Sekiguchi, Takeshi; Taguchi, Yutaka; Hirayama, Naomi; Nishio, Keishi; Takanashi, Yoshifumi

2014-10-01

166

Concepts for central solar electric power generation  

NASA Technical Reports Server (NTRS)

The investigation reported was conducted to select the best conceptual design of a power plant for the dynamic conversion of solar heat to electricity. Conversion of thermal energy to electricity was to be an accomplished with conventional turbomachinery. Questions of site selection are discussed along with solar energy collection systems, aspects of candidate system definition, and reference systems.

Kintigh, J. K.

1974-01-01

167

Review of pulsed rf power generation  

SciTech Connect

I am going to talk about pulsed high-power rf generation for normal-conducting electron and positron linacs suitable for applications to high-energy physics in the Next Linear Collider, or NLC. The talk will cover some basic rf system design issues, klystrons and other microwave power sources, rf pulse-compression devices, and test facilities for system-integration studies.

Lavine, T.L.

1992-04-01

168

Dislocation Generation by Thermal Stresses in Si: Modeling and Experiments  

SciTech Connect

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.

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

2005-11-01

169

Ontario Power Generation's green response program  

Microsoft Academic Search

Summary form only given as follows. Competition in the electricity market is driving the need for generation companies to lower cost, increase output and at the same time meet strict environmental obligations. Change is probably the only constant in the new market. To help respond to the new challenges, Ontario Power Generation worked with others to develop cost effective solutions

S. Rouse

2002-01-01

170

Compact pulsed power generators for industrial applications  

Microsoft Academic Search

Summary form only given as follows. Compact pulsed power generators using high-power semiconductor switches are being developed at Nagaoka University of Technology, in collaboration with partners from Japanese industry. The switching units involved in these studies are the most up-to-date semiconductor switches such as static-induction thyristor (SI-thyristor), insulated gate bipolar transistor (IGBT), high-power metal-oxide-semiconductor field effect transistor (MOSFET), and semiconductor

W. Jiang; K. Yatsui; N. Shimizu; K. Iida; A. Tokuchi

2003-01-01

171

Power generation potential of biomass gasification systems  

SciTech Connect

Biomass has the potential to contribute a significant portion of the electricity consumed in industrialized nations and a major share of the power mix in developing countries. In addition to providing an alternative to fossil-fuel-based energy and creating new markets for agriculture, a renewable resource like biomass used in a sustainable fashion facilitates closure of the carbon cycle. To realize these benefits, particularly in the shadow of uncertainties cast by deregulation and recent changes in federal energy and agricultural policies, biomass power systems must be competitive with incumbent power-generation technologies in terms of generation efficiency and overall cost. Anticipated performance and cost of biomass-based integrated gasification, combined-cycle power systems are discussed. The electric power that can be generated worldwide using existing biomass resources (primarily crop residues and wastes) and the potential amount that could be generated from crops grown specifically for electricity generation are projected. Technical and economic obstacles that must be overcome before advanced biomass-power systems based on aeroderivative turbines or fuel cells can become fully commercial are identified. Research, development, and demonstration efforts under way or being planned to overcome those obstacles are described; developments in a major biomass gasification demonstration project taking place in Hawaii under the auspices of the US Department of Energy and the State of Hawaii are detailed.

Kinoshita, C.M.; Turn, S.Q. [Univ. of Hawaii, Honolulu, HI (United States); Overend, R.P.; Bain, R.L. [National Renewable Energy Lab., Golden, CO (United States)

1997-12-01

172

Synthetic thermal image generation for combat vehicle identification  

Microsoft Academic Search

There is a need for a cost-effective approach to training ground forces in combat vehicle identification (CVI), especially under thermal sighting conditions. Computer image generation (CIG) provides many advantages for the development of cost effective CVI training: 3-D and thermal modeling of vehicles, thermal rendering of landscape scenes, and a wide assortment of training scenarios. But the extent of computation

James I. Montgomery; David Graff; B. P. Landell

1992-01-01

173

Small nuclear power generation units, and electric power system interconnection  

Microsoft Academic Search

In this paper, we introduced a new paradigm for energy supply system in near future which produces electric and district heat cogeneration with dispersed power grid with small nuclear power generation units (SNPGU). Recently, in nuclear field, a lot of effort has been done in nuclear major countries to develop small and medium reactor for enhancement of nuclear peaceful use

Sang-Seung Lee; Jong-Keun Park; Seung-Il Moon; Yong-Tae Yoon; Jong-Won Kim; Goon-Cherl Park

2006-01-01

174

Optimisation of Concentrating Solar Thermal Power Plants with Neural Networks  

E-print Network

Optimisation of Concentrating Solar Thermal Power Plants with Neural Networks Pascal Richter1 introduce our tool for the optimisation of parameterised solar thermal power plants, and report the applicability of our approach. Keywords: Optimization, Solar thermal power plants, Neural networks, Genetic

Ábrahám, Erika

175

Heat generating compositions for thermal batteries  

Microsoft Academic Search

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

V. N. Sheptunov

1991-01-01

176

Heat Generating Compositions for Thermal Batteries.  

National Technical Information Service (NTIS)

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 c...

V. N. Sheptunov

1991-01-01

177

Steam generators of the power-generating units of nuclear power plants with vver-1000 reactors  

Microsoft Academic Search

The first power-generating units at nuclear power plants with VVER-1000 reactors came on line in 1980. By August 1993 there were 19 such units (seven in Russia, ten in Ukraine, and two in Bulgaria). It was found that from the end of 1986 to 1991 the outlet ({open_quotes}cold{close_quotes}) coolant collectors of the PGV-1000 steam generators (1000 M) in these power-generating

Titov

1995-01-01

178

A Thermoelectric Generation System and Its Power Electronics Stage  

NASA Astrophysics Data System (ADS)

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.

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

2012-06-01

179

External cost of air pollution from thermal power plants: case of Greece  

Microsoft Academic Search

Purpose – The purpose of the paper is to quantify the external cost of airborne pollutants (i.e. sulphur and nitrogen oxides, carbon dioxide, and particulate matters) generated during electricity production in the thermal power plants in Greece. Design\\/methodology\\/approach – This paper applies the EcoSenseLE online tool to examine the external cost of air pollution generated in all thermal power stations

Dimitrios A. Georgakellos

2007-01-01

180

Phase change material thermal power generator  

NASA Technical Reports Server (NTRS)

An energy producing device, for example a submersible vehicle for descending or ascending to different depths within water or ocean, is disclosed. The vehicle comprises a temperature-responsive material to which a hydraulic fluid is associated. A pressurized storage compartment stores the fluid as soon as the temperature-responsive material changes density. The storage compartment is connected with a hydraulic motor, and a valve allows fluid passage from the storage compartment to the hydraulic motor. An energy storage component, e.g. a battery, is connected with the hydraulic motor and is charged by the hydraulic motor when the hydraulic fluid passes through the hydraulic motor. Upon passage in the hydraulic motor, the fluid is stored in a further storage compartment and is then sent back to the area of the temperature-responsive material.

Jones, Jack A. (Inventor); Chao, Yi (Inventor); Valdez, Thomas I. (Inventor)

2011-01-01

181

Solar thermal electric power information user study  

SciTech Connect

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

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

1981-02-01

182

Use of a Best Estimate Power Monitoring Tool to Maximize Power Plant Generation  

SciTech Connect

The Best Estimate Power Monitor (BEPM) is a tool that was developed to maximize nuclear power plant generation, while ensuring regulatory compliance in the face of venturi fouling, industry ultra-sonic flowmeter issues and other technical challenges. The BEPM uses ASME approved 'best estimate' methodology described in PTC 19.1-1985, 'Measurement Uncertainty', Section 3.8, 'Weighting Method'. The BEPM method utilizes many different and independent indicators of core thermal power and independently computes the core thermal power (CTP) from each parameter. The uncertainty of each measurement is used to weight the results of the best estimate computation of CTP such that those with lower uncertainties are weighted more heavily in the computed result. The independence of these measurements is used to minimize the uncertainty of the aggregate result, and the overall uncertainty can be much lower than the uncertainties of any of the individual measured parameters. Examples of the Balance of Plant parameters used in the BEPM are turbine first stage pressure, venturi feedwater flow, condensate flow, main steam flow, high pressure turbine exhaust pressure, low pressure turbine inlet pressure, the two highest pressure feedwater heater extraction pressures, and final feedwater temperature. The BEPM typically makes use of installed plant instrumentation that provide data to the plant computer. Therefore, little or no plant modification is required. In order to compute core thermal power from the independent indicators, a set of baseline data is used for comparison. These baseline conditions are taken from a day when confidence in the value of core thermal power is high (i.e., immediately post outage when venturi fouling is not an issue or from a formal tracer test). This provides the reference point on which to base the core thermal power calculations for each of the independent parameters. The BEPM is effective only at the upper end of the power range, where the independent parameters generally vary in a highly predictable way with changes in core thermal power. This paper will present a detailed description of the BEPM methodology, examples of the BEPM output, and examples of field application. Industry applications of the BEPM include monitoring venturi fouling, verification of an ultrasonic flow meter when used as in input to the secondary calorimetric, and monitoring the performance of other plant equipment that can affect core thermal power. When used routinely as part of a thermal performance monitoring program, the BEPM can be extremely effective in generation maximization, identification of equipment degradation or failure, and identification of potential overpower conditions. (author)

Dziuba, Lindsey L. [ILD, Inc., 8867 Highland Road n.378, Baton Rouge, Louisiana, 70808 (United States)

2006-07-01

183

43 CFR 431.6 - Power generation estimates.  

Code of Federal Regulations, 2010 CFR

...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....

2010-10-01

184

43 CFR 431.4 - Power generation responsibilities.  

Code of Federal Regulations, 2010 CFR

...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....

2010-10-01

185

43 CFR 431.4 - Power generation responsibilities.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Power generation responsibilities. 431.4 Section...INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE, AND REPLACEMENT...ARIZONA/NEVADA § 431.4 Power generation responsibilities. (a)...

2011-10-01

186

43 CFR 431.6 - Power generation estimates.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Power generation estimates. 431.6 Section 431...INTERIOR GENERAL REGULATIONS FOR POWER GENERATION, OPERATION, MAINTENANCE, AND REPLACEMENT...ARIZONA/NEVADA § 431.6 Power generation estimates. Reclamation...

2011-10-01

187

The Meteosat Second Generation (MSG) power system  

SciTech Connect

Under the direction of the European Meteorological Satellite Organization (EUMETSAT) and the European Space Agency (ESA), space industries within Europe are in the process of developing a new series of larger and more performant geostationary weather satellites. The initial three spacecraft within this new series, which are known by the name of Meteosat Second Generation (MSG), are due to be progressively launched from the year 2000 onwards. The major objective of this mission is the continuation of the European weather watch and space borne atmospheric sensing services provided by the present series of Meteosat spacecraft. To satisfy this mission requirement, the payload compliment to be supported by MSG will consist of a comprehensive earth viewing instrument capable of operating in both the infra-red and visible spectrum, an earth radiation measurement system and a search and rescue facility. In furnishing the power needs for these payloads, the power generating element on the spin stabilized MSG spacecraft consists of a body mounted solar array, capable of providing 628 watts of electrical power at the end of seven years of geosynchronous orbital lifetime. The energy storage elements for the spacecraft consists of two, 29 ampere-hour batteries, while centralized power management is achieved by the Power Control Unit (PCU), which satisfies the payload and battery re-charge demands by controlling the available solar array power. Power distribution for the spacecraft electrical loads and heaters is achieved by the Power Distribution Unit (PDU) and for the pyrotechnic devices by the Pyrotechnic Release Unit.

Haines, J.E.; Levins, D.; Robben, A.; Sepers, A. [European Space Agency, Noordwijk (Netherlands). Power and Energy Conversion Div.

1997-12-31

188

Solar Stirling power generation - Systems analysis and preliminary tests  

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

189

Analysis of Wind Power Generation of Texas  

E-print Network

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...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...

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

190

Biomass gasifier gas turbine power generating technology  

Microsoft Academic Search

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.

R. H. Williams; E. D. Larson

1996-01-01

191

Advanced Coal-Based Power Generations  

NASA Technical Reports Server (NTRS)

Advanced power-generation systems using coal-derived fuels are evaluated in two-volume report. Report considers fuel cells, combined gas- and steam-turbine cycles, and magnetohydrodynamic (MHD) energy conversion. Presents technological status of each type of system and analyzes performance of each operating on medium-Btu fuel gas, either delivered via pipeline to powerplant or generated by coal-gasification process at plantsite.

Robson, F. L.

1982-01-01

192

Entropy-generated power and its efficiency.  

PubMed

We propose a simple and analytically solvable model for a motor that generates mechanical motion by exploiting an entropic force arising from the topology of the underlying phase space. We show that the generation of mechanical forces in our system is surprisingly robust to local changes in kinetic and topological parameters. Furthermore, we find that the efficiency at maximum power of the motor may show discontinuities. PMID:24229124

Golubeva, N; Imparato, A; Esposito, M

2013-10-01

193

Entropy-generated power and its efficiency  

NASA Astrophysics Data System (ADS)

We propose a simple and analytically solvable model for a motor that generates mechanical motion by exploiting an entropic force arising from the topology of the underlying phase space. We show that the generation of mechanical forces in our system is surprisingly robust to local changes in kinetic and topological parameters. Furthermore, we find that the efficiency at maximum power of the motor may show discontinuities.

Golubeva, N.; Imparato, A.; Esposito, M.

2013-10-01

194

A Thermoelectric Generator Using Porous Si Thermal Isolation  

PubMed Central

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

Hourdakis, Emmanouel; Nassiopoulou, Androula G.

2013-01-01

195

Thermal Analysis of Piezoelectric Benders with Laminated Power Electronics  

E-print Network

Thermal Analysis of Piezoelectric Benders with Laminated Power Electronics Andrew J. Fleming1 with integrated high voltage power electronics. Such devices dramatically simplify the application of piezoelectric actuators since the power electronics are already optimized for the voltage range, capacitance

Fleming, Andrew J.

196

An efficient way to use medium-or-low temperature solar heat for power generation – integration into conventional power plant  

Microsoft Academic Search

This paper demonstrates that the medium-or-low temperature solar heat can be used to generate power efficiently by integrating into conventional coal-fired power plants. In so-called solar aided power generation (SAPG) technology, medium-or-low temperature solar heat is used to replace parts of bled-off steams in regenerative Rankine cycle to pre-heat feedwater. Thermal oil can be used as solar heat carrier and

Yongping Yang; Qin Yan; Rongrong Zhai; Abbas Kouzani; Eric Hu

2011-01-01

197

Using thermoelectric nuclear power generators in spacecraft power-generation propulsion complexes  

Microsoft Academic Search

Power-generation and propulsion complexes for spacecraft, universal space platforms (US) which combine a power unit and high- and low-thrust propulsion unions, make it possible to efficiently solve problems involved in creating satellite communication systems, environmental monitoring systems, industrial technology platforms, interorbital shuttles, etc. Electrical power consumed by prospective spacecraft designed for communication or environmental monitoring may be as high as

P. V. Andreev; A. Ya. Galkin; G. M. Gryaznov

1994-01-01

198

Electrical, thermal and optical characterization of power LED assemblies  

Microsoft Academic Search

Besides their electrical properties the optical parameters of LEDs also depend on junction temperature. For this reason thermal characterization and thermal management play important role in case of power LEDs, necessitating both physical measurements and simulation tools. The focus of this paper is a combined electrical, thermal and optical characterization of power LED assemblies. In terms of simulation a method

András Poppe; Gábor Farkas; G. Horvath

2007-01-01

199

Photovoltaic Generation Of Power By Utilities  

NASA Technical Reports Server (NTRS)

Bibliography of recent documents on photovoltaic generation of electric power divided into two subject areas: (1) central-station systems and (2) residential and intermediate systems. Further divided into design options, performance modeling, construction experience, operating experience, economics and costs, and integration with utilities. Reports, papers, and books included. Bibliography lists 79 references.

Sugimura, Russell S.; Wood, Joan M.

1989-01-01

200

Plasma plume MHD power generator and method  

DOEpatents

A method is described of generating power at a situs exposed to the solar wind which comprises creating at separate sources at the situs discrete plasma plumes extending in opposed directions, providing electrical communication between the plumes at their source and interposing a desired electrical load in the said electrical communication between the plumes.

Hammer, J.H.

1993-08-10

201

Power generation from LNG vaporization. Technical memo  

Microsoft Academic Search

A method of generating electrical power to take full advantage of the energy released in the vaporization of LNG is described. The process is one of many which might be used to recover energy from the cryogenic LNG-oil slurry pipeline. The process of cooling and liquefying natural gas consumes large amounts of energy which is, in a sense, stored in

Rennert

1975-01-01

202

Environmental effects of tidal power generating schemes  

Microsoft Academic Search

The Severn Estuary has been proposed as a site for a tidal power generating barrage. The character of the existing environment would be changed but, if the risks of accumulating pollutants and eutrophication can be avoided, the reduction in turbidity and tidal scour could increase species diversity and productivity. The interests of wading birds and wildfowl could be accommodated by

C. Mettam

1978-01-01

203

Status and perspectives of fossil power generation  

Microsoft Academic Search

According to forecasts made by the World Energy Conference and other organizations, fossil fuels such as coal, oil and natural gas will be, in the foreseeable future, our main source for power generation. It is, therefore, very important to use these non-renewable resources with great care and utilize them only in highly efficient plants. This not only conserves our limited

Bert Rukes; Robert Taud

2004-01-01

204

Thermoelectric unicouple used for power generation  

NASA Technical Reports Server (NTRS)

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.

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

2004-01-01

205

The New Generation of Thermal Mapping  

ERIC Educational Resources Information Center

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…

Patterson, Valerie B.

2012-01-01

206

Optical generation of radio-frequency power  

SciTech Connect

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%.

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

1994-11-01

207

Photovoltaic Power Generation in the Stellar Environments  

E-print Network

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.

T. E. Girish; S. Aranya

2010-12-03

208

Efficient, monochromatic, high-power microwave generator  

SciTech Connect

Microwave generation by electron beams in virtual cathode configurations can achieve significant power levels. However, most designs inherently have two competing mechanisms generating microwaves; namely the oscillating virtual cathode and the reflexing electrons. These two mechanisms tend to interfere destructively with each other. Specifically, the reflexing electrons subject the electron beam to two-stream instability, causing considerable heating of the electron beam. In addition, the space-charge of the reflexing electrons can cause the diode independence to fluctuate, resulting in oscillations of the electron beam energy. We have investigated a novel idea to remove these undesirable effects and we found that high-power, narrow-band, and monochromatic microwaves could be generated with efficiency of 10 to 20%. 16 refs., 7 figs.

Kwan, T.J.T.; Snell, C.M.

1986-01-01

209

Next Generation Integrated Power System: The backbone of the electric warship(Hybrid Electric Drive: A near term opportunity)  

Microsoft Academic Search

Advances in materials, controls, packaging, thermal management have played a significant role in improving efficiencies, power density, availability of power, and other desirable metrics in electric power systems. The US Navy, leveraging these advances, and in cooperation with industry, is developing the necessary architectures and modular building blocks, or pieces, consisting of power generation, power conversion, energy storage, power distribution,

Lynn J. Petersen

2009-01-01

210

Thermal component models for electro thermal analysis of multichip power modules  

Microsoft Academic Search

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

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

2002-01-01

211

Modeling of solar thermal selective surfaces and thermoelectric generators  

E-print Network

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 ...

McEnaney, Kenneth

2010-01-01

212

Solar electric power generation, volume 2. Citations from the NTIS data base  

Microsoft Academic Search

Citations of Federally-funded research are presented pertaining to electric power generation by both direct conversion with solar cells and indirect conversion using solar heat. Topic areas cover equipment design, site surveys, economics, and feasibility studies of solar power satellite systems, photovoltaic systems, solar total energy systems, and central receiver solar thermal power systems. A few abstracts deal with phase change

A. S. Hundemann

1978-01-01

213

Thermoelectric power generation for hybrid-electric vehicle auxiliary power  

NASA Astrophysics Data System (ADS)

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.

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

2009-03-01

214

Thermal modeling of lithium systems. [heat generation  

NASA Technical Reports Server (NTRS)

The heat generation during cell discharge and its distribution are discussed. The effects of casing materials, thickness of current collectors, discharge environments, and entropies are described. A number of calorimetric experiments are described which quantify the heat during cell discharge.

Kim, K. Y.

1981-01-01

215

Thermoelectric power generation for battery charging  

SciTech Connect

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 battery charger developed, consists of a thermoelectric converter system, powered from butane gas, and a dc-to-dc boost up converter. Both the sub-assemblies are designed using computer models and constructed. The unit produces an output power of 5 watts which doubles the life of the lap-top computer`s internal batteries.

Rahman, M. [Bangladesh Univ. of Engineering and Technology, Dhaka (Bangladesh); Shuttleworth, R. [Univ. of Manchester (United Kingdom). Electrical Engineering Lab.

1995-12-31

216

Use of electricity price to match heat load with wind power generation  

Microsoft Academic Search

The synergy between electrically heated buildings and wind power generation is analyzed in this paper, with a view to providing lower cost heating and a demand side management resource that will facilitate the growth of renewable generation. The paper begins by demonstrating the relationship between electricity price and wind generation based upon recent market data from Ireland. Thermal parameters from

J. Kennedy; B. Fox; D. Flynn

2009-01-01

217

Thermophotovoltaic and thermoelectric portable power generators  

NASA Astrophysics Data System (ADS)

The quest for developing clean, quiet, and portable high energy density, and ultra-compact power sources continues. Although batteries offer a well known solution, limits on the chemistry developed to date constrain the energy density to 0.2 kWh/kg, whereas many hydrocarbon fuels have energy densities closer to 13 kWh/kg. The fundamental challenge remains: how efficiently and robustly can these widely available chemical fuels be converted into electricity in a millimeter to centimeter scale systems? Here we explore two promising technologies for high energy density power generators: thermophotovoltaics (TPV) and thermoelectrics (TE). These heat to electricity conversion processes are appealing because they are fully static leading to quiet and robust operation, allow for multifuel operation due to the ease of generating heat, and offer high power densities. We will present some previous work done in the TPV and TE fields. In addition we will outline the common technological barriers facing both approaches, as well as outline the main differences. Performance for state of the art research generators will be compared as well as projections for future practically achievable systems. A viable TPV or TE power source for a ten watt for one week mission can be built from a <10% efficient device which is achievable with current state of the art technology such as photonic crystals or advanced TE materials.

Chan, Walker R.; Waits, Christopher M.; Joannopoulos, John D.; Celanovic, Ivan

2014-06-01

218

Value of Concentrating Solar Power and Thermal Energy Storage  

SciTech Connect

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.

Sioshansi, R.; Denholm, P.

2010-02-01

219

ZERO EMISSION POWER GENERATION TECHNOLOGY DEVELOPMENT  

SciTech Connect

Clean Energy Systems (CES) was previously funded by DOE's ''Vision 21'' program. This program provided a proof-of-concept demonstration that CES' novel gas generator (combustor) enabled production of electrical power from fossil fuels without pollution. CES has used current DOE funding for additional design study exercises which established the utility of the CES-cycle for retrofitting existing power plants for zero-emission operations and for incorporation in zero-emission, ''green field'' power plant concepts. DOE funding also helped define the suitability of existing steam turbine designs for use in the CES-cycle and explored the use of aero-derivative turbines for advanced power plant designs. This work is of interest to the California Energy Commission (CEC) and the Norwegian Ministry of Petroleum & Energy. California's air quality districts have significant non-attainment areas in which CES technology can help. CEC is currently funding a CES-cycle technology demonstration near Bakersfield, CA. The Norwegian government is supporting conceptual studies for a proposed 40 MW zero-emission power plant in Stavager, Norway which would use the CES-cycle. The latter project is called Zero-Emission Norwegian Gas (ZENG). In summary, current engineering studies: (1) supported engineering design of plant subsystems applicable for use with CES-cycle zero-emission power plants, and (2) documented the suitability and availability of steam turbines for use in CES-cycle power plants, with particular relevance to the Norwegian ZENG Project.

Ronald Bischoff; Stephen Doyle

2005-01-20

220

Thermal analyses of power subsystem components  

NASA Technical Reports Server (NTRS)

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.

Morehouse, Jeffrey H.

1990-01-01

221

Complementary power output characteristics of electromagnetic generators and triboelectric generators.  

PubMed

Recently, a triboelectric generator (TEG) has been invented to convert mechanical energy into electricity by a conjunction of triboelectrification and electrostatic induction. Compared to the traditional electromagnetic generator (EMG) that produces a high output current but low voltage, the TEG has different output characteristics of low output current but high output voltage. In this paper, we present a comparative study regarding the fundamentals of TEGs and EMGs. The power output performances of the EMG and the TEG have a special complementary relationship, with the EMG being a voltage source and the TEG a current source. Utilizing a power transformed and managed (PTM) system, the current output of a TEG can reach as high as ?3 mA, which can be coupled with the output signal of an EMG to enhance the output power. We also demonstrate a design to integrate a TEG and an EMG into a single device for simultaneously harvesting mechanical energy. In addition, the integrated NGs can independently output a high voltage and a high current to meet special needs. PMID:24595200

Fan, Feng-Ru; Tang, Wei; Yao, Yan; Luo, Jianjun; Zhang, Chi; Wang, Zhong Lin

2014-04-01

222

Electrokinetic Power Generation from Liquid Water Microjets  

SciTech Connect

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%.

Duffin, Andrew M.; Saykally, Richard J.

2008-02-15

223

Thermal Decomposition of Furan Generates Propargyl Radicals  

SciTech Connect

The thermal decomposition of furan has been studied by a 1 mm x 2 cm tubular silicon carbide reactor, C{sub 4}H{sub 4}O + {Delta} {yields} 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 {micro}s) 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.

Vasiliou, A.; Nimlos, M. R.; Daily, J. W.; Ellison, G. B.

2009-07-01

224

ADVANCED CO2 CYCLE POWER GENERATION  

SciTech Connect

Research is being conducted under United States Department of Energy (DOE) Contract DE-FC26-02NT41621 to develop a conceptual design and determine the performance characteristics of a new IGCC plant configuration that facilitates CO{sub 2} removal for sequestration. This new configuration will be designed to achieve CO{sub 2} sequestration without the need for water gas shifting and CO{sub 2} separation, and may eliminate the need for a separate sequestration compressor. This research introduces a novel concept of using CO{sub 2} as a working fluid for an advanced coal gasification based power generation system, where it generates power with high system efficiency while concentrating CO{sub 2} for sequestration. This project supports the DOE research objective of development of concepts for the capture and storage of CO{sub 2}.

A. Nehrozoglu

2004-01-01

225

ADVANCED CO2 CYCLE POWER GENERATION  

SciTech Connect

Research is being conducted under United States Department of Energy (DOE) Contract DE-FC26-02NT41621 to develop a conceptual design and determine the performance characteristics of a new IGCC plant configuration that facilitates CO{sub 2} removal for sequestration. This new configuration will be designed to achieve CO{sub 2} sequestration without the need for water gas shifting and CO{sub 2} separation, and may eliminate the need for a separate sequestration compressor. This research introduces a novel concept of using CO{sub 2} as a working fluid for an advanced coal gasification based power generation system, where it generates power with high system efficiency while concentrating CO{sub 2} for sequestration. This project supports the DOE research objective of development of concepts for the capture and storage of CO{sub 2}.

A. Nehrozoglu

2003-10-01

226

Electric generating prospects for nuclear power  

Microsoft Academic Search

Most of the nuclear power plants in the U.S. today are of the light-water variety. In many parts of the U.S. these plants are competitive with plants burning coal, but the electricity that they generate will be more costly in the future as uranium supplies deplete. A promising possible answer to the cost problem is the fast-neutron reactor, which produces

Manson Benedict

1970-01-01

227

Thermophotovoltaic (TPV) applications to space power generation  

SciTech Connect

Examined is a Thermophotovoltaic (TPV) converter using an advanced quaternary III--V cell with an integral filter coupled to isotope (GPHS) and nuclear reactor heat sources. Results presented indicate the merits of TPV conversion for meeting a wide range of space power requirements. The authors find that TPV offers both a reduction in the cost of building the converter for an electric generator driven by a radioisotope or nuclear reactor, as well as appreciable fuel savings. On the basis of cost, they find that isotope powered TPV systems enjoy considerable advantage over solar arrays or interplanetary exploration missions beyond the asteroid belt. For space reactor power systems the analysis indicates that TPV conversion has a mass advantage over thermoelectrics (T/E) for systems below 50 kWe.

Vicente, F.A.; Kelly, C.E.; Loughin, S. [Lockheed Martin Missiles and Space, Philadelphia, PA (United States)

1996-12-31

228

INDUCTION HEATING OF CARBON-FIBER COMPOSITES: THERMAL GENERATION MODEL  

EPA Science Inventory

A theory of local and global mechanisms of heat generation and distribution in carbon-fiber-based composites subjected to an alternating magnetic field has been proposed. A model that predicts the strength and distribution of thermal generation through the thickness of carbon-fib...

229

Cummins Power Generation SECA Phase 1  

SciTech Connect

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.

Charles Vesely

2007-08-17

230

Piezoelectric capacitive power generator from vibration energy  

NASA Astrophysics Data System (ADS)

A vibration-powered micro-power-generator has been presented in this paper, which has integrated two different energy harvesting mechanisms, e.g., Capacitive and Piezoelectric Mechanisms. The periodic vibration of the mass on movable electrode causes the variation of the capacitance, and the strain in the piezoelectric film. These two mechanisms can harvest the vibration energy and generate current in the output circuit. By using two different metals with large difference in working function as the two electrodes of the capacitor, our design, the combination of these two different scavenge mechanisms, can overcome the dependence of the traditional capacitive converter on the separate voltage source and improve the efficiency of power conversion. The volume of the designed device is less than 0.8 cm 3. The simulated results reveal that this energy converter can provide an average output power of 82.21?W at an external vibration with a frequency of 111.4 Hz and amplitude of 0.2g.

Zhang, Yangjian; Li, Lin; San, Haisheng; Chen, Xuyuan

2008-03-01

231

Options for Control of Reactive Power by Distributed Photovoltaic Generators  

E-print Network

High penetration levels of distributed photovoltaic(PV) generation on an electrical distribution circuit present several challenges and opportunities for distribution utilities. Rapidly varying irradiance conditions may cause voltage sags and swells that cannot be compensated by slowly responding utility equipment resulting in a degradation of power quality. 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 discuss and compare via simulation various design options for control systems to manage the reactive power generated by these inverters. An important design decision that weighs on the speed and quality of communication required is whether the control should be centralized or distributed (i.e. local). In general, we find that local control schemes are capable for maintaining voltage within acceptable bounds. We consider the benefits of choosing different local variables on which to control and how the control system can be continuously tuned between robust voltage control, suitable for daytime operation when circuit conditions can change rapidly, and loss minimization better suited for nighttime operation.

Petr Sulc; Konstantin Turitsyn; Scott Backhaus; Michael Chertkov

2010-08-04

232

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

SciTech Connect

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.

Pitts, J.H.

1986-07-31

233

Lead telluride as a thermoelectric material for thermoelectric power generation  

NASA Astrophysics Data System (ADS)

The specialized applications of thermoelectric generators are very successful and have motivated a search for materials with an improved figure of merit Z, and also for materials which operate at elevated temperatures. Lead telluride, PbTe, is an intermediate thermoelectric power generator. Its maximum operating temperature is 900 K. PbTe has a high melting point, good chemical stability, low vapor pressure and good chemical strength in addition to high figure of merit Z. Recently, research in thermoelectricity aims to obtain new improved materials for autonomous sources of electrical power in specialized medical, terrestial and space applications and to obtain an unconventional energy source after the oil crises of 1974. Although the efficiency of thermoelectric generators is rather low, typically ?5%, the other advantages, such as compactness, silent, reliability, long life, and long period of operation without attention, led to a wide range of applications. PbTe thermoelectric generators have been widely used by the US army, in space crafts to provide onboard power, and in pacemakers batteries. The general physical properties of lead telluride and factors affecting the figure of merit have been reviewed. Various possibilities of improving the figure of merit of the material have been given, including effect of grain size on reducing the lattice thermal conductivity ?L. Comparison of some transport properties of lead telluride with other thermoelectric materials and procedures of preparing compacts with transport properties very close to the single crystal values from PbTe powder by cold and hot-pressing techniques are discussed.

Dughaish, Z. H.

2002-09-01

234

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

NASA Technical Reports Server (NTRS)

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.

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

1989-01-01

235

Nonlinear models for mechanical energy production in imperfect generators driven by thermal or solar energy  

Microsoft Academic Search

In this paper we show how the nonlinear kinetics of energy transfer in propelling fluids and imperfect (non-Carnot) thermal machines can be imbed into the contemporary theory of irreversible energy generators and heat pumps. We quantitatively describe effects of nonlinear heat transfer assuming that heat fluxes are proportional to the difference of temperature in certain power, Ta. We also show

Stanislaw Sieniutycz; Piotr Kuran

2005-01-01

236

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

Microsoft Academic Search

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

J. P. Reichling; F. A. Kulacki

2008-01-01

237

Solar Power Satellite Thermal Control Approach  

NASA Astrophysics Data System (ADS)

The concept of generating solar power in space and transmitting it to earth or any other desired destination such as a planet, moon, or to charge a space vehicle via microwaves, stems from a wide variety of human needs and necessities. It is now a well-known fact that world population increases at a very rapid rate, nearly 80 millions or more per year, and the world-wide energy demand seems to double in the course of the present century. If technology has to advance at the present rate, in phase with high living standards, energy growth must not lag behind. These estimates are based on the population growth rate in the developing countries and the simultaneous increase in per capita energy consumption in these countries, coupled with economical boost. In most of the underdeveloped countries energy needs are of small scales, faraway from the power distribution line and can be very easily satisfied by harnessing solar energy. Furthermore, the Earth temperature has increased by 0.5° to 1° F during the past century. This rise in temperature is believed to have been caused by the use of oil, coal, and natural gas (fossil fuels) for transportation and energy production. Actually, fossil fuel combustion-based power plants are the dominant sources for energy demands. Therefore, increased power production will accelerate the production of greenhouse gases (predominantly CO2). To cope with their energy needs, countries could be engaged in the use of nuclear energy, which could accelerate the diffusion of nuclear arms as a bye- product.

Sacchi, E.; Cassisa, G.; Gottero, M.

2004-12-01

238

Output power analyses for the thermodynamic cycles of thermal power plants  

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

239

Power, and the next generation. [The next generation of power sources  

SciTech Connect

What's on the horizon for electric generation The World Energy Conference predicts an energy demand of roughly 20 billion metric tons coal equivalent in the year 2020. That requires an increase in the worldwide power generation capacity of about 20 [times] 1012 kilowatt-hours per year. Most of the increase will occur in coal-fired facilities, followed by natural gas-fired units, and then by nuclear and hydro plants. Other power generating ideas include a solar/combined cycle power plant, oil production from oil shale, and integrated coal gasification combined cycle plants. These plants will have a minimum of air pollution and solid waste production, producing electric power and byproducts such as methanol and gasoline.

Termuehlen, H.

1994-12-01

240

Solar salt pond potential site survey for electrical power generation  

NASA Technical Reports Server (NTRS)

A solar salt gradient pond acts as a passive heat sink or thermal battery in which energy can be recovered through the conversion of thermal energy into electrical energy. Here, a condensation of a larger report that focused on the identification of potential salt gradient pond sites in the United States using in-situ resources is presented. It is shown that there are at least 24 states that lie in a primary or secondary potential site category. Fourteen states are assigned as primary states and ten are assigned as secondary. The division is subjectively based on the severity of winter weather. The most promising states are those that lie in the southern half of the country. When the primary and secondary category states are combined with the other states that may be able to support a pond, a total of 38 states exhibit the possibility of supporting power generation sites of various size.

Hurick, M. G.

1982-01-01

241

A Comparative Study of Power Cycling and Thermal Shock Tests  

Microsoft Academic Search

Thermal shock test is a traditionally used test to simulate thermomechanical stresses experienced by electronic products during their operational life span. However, because of increasing power densities and modular design of modern consumer devices, the stresses induced by thermal shocks are becoming too different from those experienced in operational environment. Inherent deficiencies in thermal shock test include the omission of

J. Karppinen; T. Laurila; J. K. Kivilahti

2006-01-01

242

Power Generator with Thermo-Differential Modules  

NASA Technical Reports Server (NTRS)

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.

Saiz, John R.; Nguyen, James

2010-01-01

243

Application of field-modulated generator systems to dispersed solar thermal electric generation  

NASA Technical Reports Server (NTRS)

The state-of-the-art of field modulated generation system (FMGS) is presented, and the application of FMGS to dispersed solar thermal electric generation is discussed. The control and monitoring requirements for solar generation system are defined. A comparison is presented between the FMGS approach and other options and the technological development needs are discussed.

Ramakumar, R.

1979-01-01

244

Utilizing Radioisotope Power System Waste Heat for Spacecraft Thermal Management  

NASA Technical Reports Server (NTRS)

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.

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

2005-01-01

245

High thermal power density heat transfer. [thermionic converters  

NASA Technical Reports Server (NTRS)

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.

Morris, J. F. (inventor)

1980-01-01

246

Exergetic analysis of a solar thermal power system  

Microsoft Academic Search

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

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

2000-01-01

247

Investigation of the thermal mechanism of interelectrode breakdown in MHD generators  

NASA Astrophysics Data System (ADS)

The paper deals with a theoretical and experimental investigation of the thermal mechanism of breakdown in open-cycle MHD electrical power generators. An approximate theory is proposed for calculating the parameters of thermal breakdown in gaps of various width. Experimental results obtained with a K-1 MHD generator correlate well with the theory at insulating-wall temperatures above 1600 K, whereas the role of the electrical breakdown increases below this temperature. The fluctuation level of the electric field is found to be a major factor of breakdown; in the presence of fluctuations, there is a substantial decrease in breakdown voltage and breakdown time.

Bystryi, A. I.; Ganefeld, R. V.; Mazur, N. I.; Miroshnichenko, A. A.; Naletov, V. V.

1980-10-01

248

Thermoelectric Analysis for Helical Power Generation Systems  

NASA Astrophysics Data System (ADS)

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.

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

2014-06-01

249

Applicability of advanced automotive heat engines to solar thermal power  

NASA Technical Reports Server (NTRS)

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

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

1981-01-01

250

Testing the type GT10S (SGT 700) gas turbine units at the Sochi thermal power station  

Microsoft Academic Search

We present the results from thermal tests of the GT-10S gas-turbine units produced by Siemens, operating as part of PGU-39\\u000a power-generating units Nos. 1 and 2 at the Sochi thermal power station, which are the first ones of this type in Russia.

S. V. Malakhov; G. G. Ol’khovskii; V. A. Golubnichii

2006-01-01

251

Wood gasification for gas and power generation  

SciTech Connect

A wood-chip gasifier supplying 4.05 million Btu (4.27 GJ)/hr of low-Btu fuel gas to a diesel-engine power generator has demonstrated its suitability as an efficient energy alternative for isolated communities in Canada's heavily wooded northern areas. Preliminary tests with wet spruce chips (58% water) yielded a clean 112-130 Btu/CF (4.4-5.07 MJ/m/sup 3/) gas that is easily combusted in a naturally aspirated diesel engine requiring diesel fuel only or ignition purposes. Although designed as a fluidized-bed system, the gasifier operated essentially in a fixed updraft-flow mode; the wet spruce chips tended to lock together, thus preventing fluidization. A study of the social and environmental consequences of power generation via wood gasification in typical northern communities revealed adequate wood supplies, social benefits related to permanent local employment and a reliable fuel supply, and a minimal negative impact on the environment.

Verma, A.; Weisgerber, G.A.

1980-01-01

252

Stochastic Load Modeling and Optimal Dynamic Generation Control in Power Systems.  

National Technical Information Service (NTIS)

A statistical model is described for the dynamic generation control of a power boiler operating in a variable pressure mode to reduce thermally-generated stress levels in cycling units. Under current practices, a boiler is operated at the maximum design t...

A. Keyhani

1975-01-01

253

Rankine-Brayton engine powered solar thermal aircraft  

Microsoft Academic Search

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to

Charles L

2009-01-01

254

Rankline-Brayton engine powered solar thermal aircraft  

Microsoft Academic Search

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to

Charles L

2012-01-01

255

Comparison of advanced engines for parabolic dish solar thermal power plants  

NASA Technical Reports Server (NTRS)

A paraboloidal dish solar thermal power plant produces electrical energy by a two-step conversion process. The collector subsystem is composed of a two-axis tracking paraboloidal concentrator and a cavity receiver. The concentrator focuses intercepted sunlight (direct, normal insolation) into a cavity receiver whose aperture encircles the focal point of the concentrator. At the internal wall of the receiver the electromagnetic radiation is converted to thermal energy. A heat engine/generator assembly then converts the thermal energy captured by the receiver to electricity. Developmental activity has been concentrated on small power modules which employ 11- to 12-meter diameter dishes to generate nominal power levels of approximately 20 kWe. A comparison of advanced heat engines for the dish power module is presented in terms of the performance potential of each engine with its requirements for advanced technology development. Three advanced engine possibilities are the Brayton (gas turbine), Brayton/Rankine combined cycle, and Stirling engines.

Fujita, T.; Bowyer, J. M.; Gajanana, B. C.

1980-01-01

256

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

Microsoft Academic Search

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

Luis Martín; Luis F. Zarzalejo; Jesús Polo; Ana Navarro; Ruth Marchante; Marco Cony

2010-01-01

257

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

NASA Astrophysics Data System (ADS)

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.

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

2010-06-01

258

Active filter action of inverter exciting induction generator for wind power generation  

Microsoft Academic Search

This paper shows new induction generation system for wind power generation. This system has the voltage source converter (VSC) exciting induction generator and the PFC converter to transfer the real power. Rated power of the VSC is minimized by transferring all the real power into the PFC converter. However, the harmonic components in the current from the VSC has larger

Noriyuki Kimura; Tomoyuki Hamada; Katsunori Taniguchi; Toshimitsu Morizane

2008-01-01

259

Performance evaluation of solar thermal electric generation systems  

Microsoft Academic Search

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

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

2003-01-01

260

Measures of Suppressing Harmonic Pollution generated by Power Electronic Equipment  

Microsoft Academic Search

Firstly, harmonic generated by power electronic equipments and harmonic hazards are reviewed. In order to improve the quality of power supply, basic operation principles of four techniques which raise the power factor are analyzed, such as active power filter, power factor correction, PWM rectifier and matrix converter. Simultaneously, some new technologies of improving the power factor and harmonic suppression are

Zheng Zheng; Wang Cong

2009-01-01

261

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

SciTech Connect

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.

None

2010-01-01

262

43 CFR 418.16 - Using water for power generation.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2011-10-01 true Using water for power generation. 418.16 Section 418...Operations and Management § 418.16 Using water for power generation. All use of Project water for power generation must be incidental to...

2012-10-01

263

43 CFR 418.16 - Using water for power generation.  

...2014-10-01 2014-10-01 false Using water for power generation. 418.16 Section 418...Operations and Management § 418.16 Using water for power generation. All use of Project water for power generation must be incidental to...

2014-10-01

264

43 CFR 418.16 - Using water for power generation.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Using water for power generation. 418.16 Section 418...Operations and Management § 418.16 Using water for power generation. All use of Project water for power generation must be incidental to...

2013-10-01

265

43 CFR 418.16 - Using water for power generation.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Using water for power generation. 418.16 Section 418...Operations and Management § 418.16 Using water for power generation. All use of Project water for power generation must be incidental to...

2010-10-01

266

43 CFR 418.16 - Using water for power generation.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Using water for power generation. 418.16 Section 418...Operations and Management § 418.16 Using water for power generation. All use of Project water for power generation must be incidental to...

2011-10-01

267

Transmission and Generation Investment In a Competitive Electric Power Industry  

E-print Network

PWP-030 Transmission and Generation Investment In a Competitive Electric Power Industry James;PWP-030 Transmission and Generation Investment In a Competitive Electric Power Industry James Bushnell. Transmission and Generation Investment In a Competitive Electric Power Industry James Bushnell and Steven Stoft

California at Berkeley. University of

268

Effect of Heat Generation of Ultrasound Transducer on Ultrasonic Power Measured by Calorimetric Method  

NASA Astrophysics Data System (ADS)

Ultrasonic power is one of the key quantities closely related to the safety of medical ultrasonic equipment. An ultrasonic power standard is required for establishment of safety. Generally, an ultrasonic power standard below approximately 20 W is established by the radiation force balance (RFB) method as the most accurate measurement method. However, RFB is not suitable for high ultrasonic power because of thermal damage to the absorbing target. Consequently, an alternative method to RFB is required. We have been developing a measurement technique for high ultrasonic power by the calorimetric method. In this study, we examined the effect of heat generation of an ultrasound transducer on ultrasonic power measured by the calorimetric method. As a result, an excessively high ultrasonic power was measured owing to the effect of heat generation from internal loss in the transducer. A reference ultrasound transducer with low heat generation is required for a high ultrasonic power standard established by the calorimetric method.

Uchida, Takeyoshi; Kikuchi, Tsuneo

2013-07-01

269

Next Generation Thermal Barrier Coatings for the Gas Turbine Industry  

NASA Astrophysics Data System (ADS)

The aim of this study is to develop the next generation of production ready air plasma sprayed thermal barrier coating with a low conductivity and long lifetime. A number of coating architectures were produced using commercially available plasma spray guns. Modifications were made to powder chemistry, including high purity powders, dysprosia stabilized zirconia powders, and powders containing porosity formers. Agglomerated & sintered and homogenized oven spheroidized powder morphologies were used to attain beneficial microstructures. Dual layer coatings were produced using the two powders. Laser flash technique was used to evaluate the thermal conductivity of the coating systems from room temperature to 1200 °C. Tests were performed on as-sprayed samples and samples were heat treated for 100 h at 1150 °C. Thermal conductivity results were correlated to the coating microstructure using image analysis of porosity and cracks. The results show the influence of beneficial porosity on reducing the thermal conductivity of the produced coatings.

Curry, Nicholas; Markocsan, Nicolaie; Li, Xin-Hai; Tricoire, Aurélien; Dorfman, Mitch

2011-01-01

270

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

NASA Astrophysics Data System (ADS)

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.

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

2014-12-01

271

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

NASA Astrophysics Data System (ADS)

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.

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

2005-05-01

272

18 CFR 801.12 - Electric power generation.  

Code of Federal Regulations, 2011 CFR

...generation of electric power at hydro, pumped storage, and thermoelectric generating stations. Increased demands for electric...considerable potential for additional pumped storage and thermoelectric generation. The direct and indirect effects of...

2011-04-01

273

18 CFR 801.12 - Electric power generation.  

Code of Federal Regulations, 2012 CFR

...generation of electric power at hydro, pumped storage, and thermoelectric generating stations. Increased demands for electric...considerable potential for additional pumped storage and thermoelectric generation. The direct and indirect effects of...

2012-04-01

274

18 CFR 801.12 - Electric power generation.  

...generation of electric power at hydro, pumped storage, and thermoelectric generating stations. Increased demands for electric...considerable potential for additional pumped storage and thermoelectric generation. The direct and indirect effects of...

2014-04-01

275

18 CFR 801.12 - Electric power generation.  

Code of Federal Regulations, 2013 CFR

...generation of electric power at hydro, pumped storage, and thermoelectric generating stations. Increased demands for electric...considerable potential for additional pumped storage and thermoelectric generation. The direct and indirect effects of...

2013-04-01

276

Reliability problems in power-generation systems  

SciTech Connect

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.

Bryson, M.C. (ed.)

1980-01-01

277

Diagnostics on the COBRA pulsed power generator  

SciTech Connect

The COBRA pulsed power generator has a variable current pulse wave form and amplitude (95-180 ns rise time, up to 1 MA peak current). It was designed to study wire array Z pinches and X pinches, including plasma formation, pinch implosion dynamics, and pinch plasma parameters as a function of current rise time. These loads have been studied using an extensive set of diagnostics with spatial and/or temporal resolution. The set of electrical diagnostics on the COBRA generator includes Rogowski coils to monitor the total load current and the current through individual return current posts, and there is also an inductive voltage monitor. A set of extreme ultraviolet and x-ray detectors is used to study the load radiation. Wire array and X pinch plasma formation and dynamics are studied using two-frame, point projection X-pinch x-ray imaging as well as with multiframe laser probing. Flat potassium acid phtalate crystal (KAP), convex, extreme luminosity imaging conical spectrograph, and focusing spectrograph with spatial resolution with mica crystal, pinhole cameras, and a camera with a slit and a step filter set (slip step-wedge camera) can be used in each pulse to monitor the x-ray emission from the X pinch(es) and arrays in several spectral bands.

Shelkovenko, T. A.; Chalenski, D. A.; Chandler, K. M.; Douglass, J. D.; Greenly, J. B.; Hammer, D. A.; Kusse, B. R.; McBride, R. D.; Pikuz, S. A. [Laboratory of Plasma Studies, Cornell University, Rhodes Hall, Ithaca, New York 14853 (United States)

2006-10-15

278

Diagnostics on the COBRA pulsed power generator  

NASA Astrophysics Data System (ADS)

The COBRA pulsed power generator has a variable current pulse wave form and amplitude (95-180ns rise time, up to 1MA peak current). It was designed to study wire array Z pinches and X pinches, including plasma formation, pinch implosion dynamics, and pinch plasma parameters as a function of current rise time. These loads have been studied using an extensive set of diagnostics with spatial and/or temporal resolution. The set of electrical diagnostics on the COBRA generator includes Rogowski coils to monitor the total load current and the current through individual return current posts, and there is also an inductive voltage monitor. A set of extreme ultraviolet and x-ray detectors is used to study the load radiation. Wire array and X pinch plasma formation and dynamics are studied using two-frame, point projection X-pinch x-ray imaging as well as with multiframe laser probing. Flat potassium acid phtalate crystal (KAP), convex, extreme luminosity imaging conical spectrograph, and focusing spectrograph with spatial resolution with mica crystal, pinhole cameras, and a camera with a slit and a step filter set (slip step-wedge camera) can be used in each pulse to monitor the x-ray emission from the X pinch(es) and arrays in several spectral bands.

Shelkovenko, T. A.; Chalenski, D. A.; Chandler, K. M.; Douglass, J. D.; Greenly, J. B.; Hammer, D. A.; Kusse, B. R.; McBride, R. D.; Pikuz, S. A.

2006-10-01

279

Coupled generator and combustor performance calculations for potential early commercial MHD power plants  

NASA Technical Reports Server (NTRS)

A parametric study of the performance of the MHD generator and combustor components of potential early commercial open-cycle MHD/steam power plants is presented. Consideration is given to the effects of air heater system concept, MHD combustor type, coal type, thermal input power, oxygen enrichment of the combustion, subsonic and supersonic generator flow and magnetic field strength on coupled generator and combustor performance. The best performance is found to be attained with a 3000 F, indirectly fired air heater, no oxygen enrichment, Illinois no. 6 coal, a two-stage cyclone combustor with 85% slag rejection, a subsonic generator, and a magnetic field configuration yielding a constant transverse electric field of 4 kV/m. Results indicate that optimum net MHD generator power is generally compressor-power-limited rather than electric-stress-limited, with optimum net power a relatively weak function of operating pressure.

Dellinger, T. C.; Hnat, J. G.; Marston, C. H.

1979-01-01

280

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

E-print Network

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 ...

Ireland, Melissa Kara

2014-01-01

281

Analysis on Possible Introduction of PV System Considering Output Power Fluctuation and Battery Technology Employing Optimal Power Generation Mix Model  

NASA Astrophysics Data System (ADS)

This paper presents the evaluation on the impact of an extensive introduction of photovoltaic (PV) system and stationary battery technology into optimal power generation mix in Kanto and Kinki region. The introduction of solar PV system is expected to be extensively deployed in Japanese household sector and utility company in order to address the concerns of energy security and climate change. Considering this expected large-scale deployment of PV system in electric power system, it is necessary to investigate the optimal power generation mix which is technologically capable of controlling and accommodating the intermittent output-power fluctuation inherently derived from PV system. On these backgrounds, we develop both solar photovoltaic power generation model and optimal power generation mix model, including stationary battery technology, which are able to explicitly analyze the impact of PV output fluctuation in detailed resolution of time interval like 10 minutes at consecutive 365 days. Simulation results reveal that PV introduction does not necessarily increase battery technology due to the cost competitiveness of thermal power plants in load following requirement caused by PV system. Additionally, on the basis of sensitivity analysis on PV system cost, dramatic cost reduction proves to be indispensable enough for PV to supply a bulk of electricity similarly as thermal and nuclear power plant.

Komiyama, Ryoichi; Shibata, Saeko; Nakamura, Yosuke; Fujii, Yasumasa

282

Evaluation of steam generator feedwater nozzles for the effects of thermal stratification  

SciTech Connect

The potential for thermal stratification in the main feedwater (FW) line of a Pressurized Water Reactor (PWR) plant exists whenever the auxiliary feedwater is initiated. The thermal stratification phenomenon is attributed to the difference in density between the hotter normal feedwater, initially in the pipe, and the colder auxiliary feedwater introduced into the piping. The effect of thermal stratification on the fatigue life is two fold: the global bending due to the bowing effect caused by thermal stratification, and the local effect due to the fluctuation in the level of the hot-cold interface. This paper deals with the global and local effects of thermal stratification in the main feedwater line on the fatigue life of the steam generator feedwater nozzle. This nozzle, which is attached to the main feedwater line, is subjected to the effects of thermal stratification in the main feedwater line and in the nozzle itself due to the difference in the water density between the auxiliary feedwater and the steam generator. It should be noted that steam generator feedwater nozzle cracking has been a concern in the nuclear power industry since the late 1970`s.

Qashu, R.; El-Akily, N.M. [Southern California Edison Co., Irvine, CA (United States); Kuo, A. [Structural Integrity Associates, Inc., San Jose, CA (United States)

1995-12-01

283

High voltage power condition systems powered by flux compression generators  

NASA Astrophysics Data System (ADS)

Compact, high-gain magnetic flux compressors (FCGs) are convenient sources of substantial energy for plasma-physics and electron-beam-physics experiments, but the need for high-voltage, fast-rising pulses is difficult to meet directly with conventional generators. While a variety of novel concepts employing simultaneous, axially-detonated explosive systems are under development, power-conditioning systems based on fuse opening switches and high-voltage transformers constitute another approach that complements the fundamental size, weight, and configuration of the small helical flux compressor. In this paper, we consider first a basic inductive store/opening switch circuit and the implications associated with, specifically, a fuse opening switch and an FCG energy source. We develop a general solution to a transformer/opening switch circuit---which also includes (as a special case) the direct inductive store/opening switch circuit (without transformer) and we report results of one elementary experiment demonstrating the feasibility of the approach.

Reinovsky, R. E.; Lindemuth, I. R.; Vorthman, J. E.

284

Solar thermal powered desalination: membrane versus distillation technologies  

Microsoft Academic Search

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

G. Burgess; K. Lovegrove

285

Control of thermal therapies with moving power deposition field  

Microsoft Academic Search

A thermal therapy feedback control approach to control thermal dose using a moving power deposition field is developed and evaluated using simulations. A normal tissue safety objective is incorporated in the controller design by imposing constraints on temperature elevations at selected normal tissue locations. The proposed control technique consists of two stages. The first stage uses a model-based sliding mode

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

2006-01-01

286

Power Generation from Nuclear Reactors in Aerospace Applications  

NASA Technical Reports Server (NTRS)

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.

English, Robert E.

1982-01-01

287

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

E-print Network

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.

Apertet, Y; Goupil, C; Lecoeur, Ph

2011-01-01

288

Water impacts on thermoelectric power generation.  

E-print Network

??The energy-water nexus represents a complex system of correlated resources, with particular relevance to thermoelectric power plants. Since thermoelectric power plants typically depend on water… (more)

Stillwell, Ashlynn Suzanne

2013-01-01

289

Thermal Energy Corporation Combined Heat and Power Project  

SciTech Connect

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.

E. Bruce Turner; Tim Brown; Ed Mardiat

2011-12-31

290

Characteristics of carbon nanotubes based micro-bubble generator for thermal jet printing.  

PubMed

We propose a conceptional thermal printhead with dual microbubble generators mounted parallel in each nozzle chamber, where multiwalled carbon nanotubes are adopted as heating elements with much higher energy efficiency than traditional approaches using noble metals or polysilicon. Tailing effect of droplet can be excluded by appropriate control of grouped bubble generations. Characteristics of the corresponding micro-fabricated microbubble generators were comprehensively studied before the formation of printhead. Electrical properties of the microheaters on glass substrate in air and performance of bubble generation underwater focusing on the relationships between input power, device resistance and bubble behavior were probed. Proof-of-concept bubble generations grouped to eliminate the tailing effect of droplet were performed indicating precise pattern with high resolution could be realized by this kind of printhead. Experimental results revealed guidance to the geometric design of the printhead as well as its fabrication margin and the electrical control of the microbubble generators. PMID:22408940

Zhou, Wenli; Li, Yupeng; Sun, Weijun; Wang, Yunbo; Zhu, Chao

2011-12-01

291

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

NASA Technical Reports Server (NTRS)

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

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

2013-01-01

292

Thermal Analysis and Testing of Fastrac Gas Generator Design  

NASA Technical Reports Server (NTRS)

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.

Nguyen, H.

1998-01-01

293

Generation scheduling for wind power generation by storage battery system and meteorological forecast  

Microsoft Academic Search

The Ministry of Economy, Trade, and Industry in Japan published a target to install 3 GW wind power generation to be connected to grids by 2010. However, as outputs from wind power generation fluctuate time to time and wind power resources are available only in specific areas, deterioration of the quality of utilitypsilas power supply has become an important issue

T. Tanabe; T. Sato; R. Tanikawa; I. Aoki; T. Funabashi; R. Yokoyama

2008-01-01

294

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

Microsoft Academic Search

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

Shimin Wang; Amir Faghri; Theodore L. Bergman

2012-01-01

295

Thermal expansion of slag and fly ash from coal gasification in IGCC power plant  

Microsoft Academic Search

Integrated gasification in combined cycle (IGCC) is an electrical power generation system which is characterized to be a clean coal technology different than conventional process in combustible treatment. IGCC process gives rise to inorganic solid wastes in the form of vitreous slag and fly ashes with singular thermal properties. The gasification of the fuel takes place at high temperature and

M. Aineto; A. Acosta; J. Ma. Rincón; M. Romero

2006-01-01

296

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

Microsoft Academic Search

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

Mousa S. Mohsen

2004-01-01

297

On Solar Thermal Electric Power Capacity Sizing  

NASA Technical Reports Server (NTRS)

The commercialization of parabolic dish/generator modules are investigated. Design analysis indicates that a 10 sq m/ three kilowatt generator configuration is simple and easy to maintain, manufacturing is easily adaptable, the demand is already established, the unit is cost effective and the hardware is readily available.

Clark, J. S.

1984-01-01

298

Investigation of thermal storage and steam generator issues  

SciTech Connect

A review and evaluation of steam generator and thermal storage tank designs for commercial nitrate salt technology showed that the potential exists to procure both on a competitive basis from a number of qualified vendors. The report outlines the criteria for review and the results of the review, which was intended only to assess the feasibility of each design, not to make a comparison or select the best concept.

Not Available

1993-08-01

299

Direct charge radioisotope activation and power generation  

DOEpatents

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.

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

2002-01-01

300

Assessment of integrated gasification combined cycle power generation  

Microsoft Academic Search

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

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

1983-01-01

301

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

Microsoft Academic Search

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

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

1983-01-01

302

OPTIMAL DISTRIBUTED POWER GENERATION UNDER NETWORK LOAD CONSTRAINTS,  

E-print Network

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, small wind turbine or central-producers. Decentralized Power Generation (DPG) refers to an electric power source such as solar, wind or combined heat

Frank, Jason

303

Technological assessment for developing new wind power generation systems  

Microsoft Academic Search

This paper describes the technological assessment employed in the development of new wind power generation systems, which facilitate stable, controllable energy supply systems in a diversified and competitive energy market. The concept of a new wind power generation system is presented and possible solutions to technical problems for the development of new wind power systems are discussed.

Guohong Wu; T. Minakawa; M. Goto; Y. Tada

2005-01-01

304

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

305

Analysis of waste-heat thermoelectric power generators  

Microsoft Academic Search

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.

Chih Wu

1996-01-01

306

Statistical identification and optimal control of thermal power plants  

Microsoft Academic Search

Statistical system identification and its use for the optimal control of thermal power plants are discussed. The analysis of the plant dynamics and derivation of the state-space representation are performed by fitting a multivariate AR model to the plant data obtained by an experiment. The basic concept of the power plant control and the motivation that necessitated the statistical approach

H. Nakamura; Y. Toyota

1988-01-01

307

Thermal management of power electronics using thermoelectric coolers  

Microsoft Academic Search

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

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

1996-01-01

308

Analyses of MTI imagery of power plant thermal discharge  

Microsoft Academic Search

MTI images of thermal discharge from three power plants are analyzed in this paper with the aid of a 3_D hydrodynamic code. The power plants use different methods to dissipate waste heat in the environment: a cooling lake at Comanche Peak, ocean discharge at Pilgrim and cooling canals at Turkey Point. This paper show s that it is possible to

Alfred J. Garrett

2002-01-01

309

Analyses of MTI Imagery of Power Plant Thermal Discharge  

Microsoft Academic Search

MTI images of thermal discharge from three power plants are analyzed in this paper with the aid of a 3-D hydrodynamic code. The power plants use different methods to dissipate waste heat in the environment: a cooling lake at Comanche Peak, ocean discharge at Pilgrim and cooling canals at Turkey Point. This paper shows that it is possible to reproduce

2001-01-01

310

Finite element thermal study of the Linac4 plasma generator  

SciTech Connect

The temperature distribution and heat flow at equilibrium of the plasma generator of the rf-powered noncesiated Linac4 H{sup -} ion source have been studied with a finite element model. It is shown that the equilibrium temperatures obtained in the Linac4 nominal operation mode (100 kW rf power, 2 Hz repetition rate, and 0.4 ms pulse duration) are within material specifications except for the magnet cage, where a redesign may be necessary. To assess the upgrade of the Linac4 source for operation in the high-power operation mode of the Superconducting Proton Linac (SPL), an extrapolation of the heat load toward 100 kW rf power, 50 Hz repetition rate, and 0.4 ms pulse duration has been performed. The results indicate that a significant improvement of the source cooling is required to allow for operation in the high-power mode of SPL.

Faircloth, D. [STFC, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX (United Kingdom); Kronberger, M.; Kuechler, D.; Lettry, J.; Scrivens, R. [BE-ABP, Hadron Sources and Linacs, CERN, CH-1211 Geneva (Switzerland)

2010-02-15

311

Power MOSFET Thermal Instability Operation Characterization Support  

NASA Technical Reports Server (NTRS)

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.

Shue, John L.; Leidecker, Henning

2010-01-01

312

Thermocline Thermal Storage Test for Large-Scale Solar Thermal Power Plants  

Microsoft Academic Search

Solar thermal-to-electric power plants have been tested and investigated at Sandia National Laboratories (SNL) since the late 1970s, and thermal storage has always been an area of key study because it affords an economical method of delivering solar-electricity during non-daylight hours. This paper describes the design considerations of a new, single-tank, thermal storage system and details the benefits of employing

S. T. LAURENT; STEVEN J

2000-01-01

313

Thermal storage with molten salt for peaking power  

Microsoft Academic Search

An improvement in the process for the generation of electrical power is described in which heat released by exhaust gases derived from the combustion of gaseous products in a coal gasification process is stored and utilized to generated increased electrical power during peak demand periods.

1978-01-01

314

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

NASA Astrophysics Data System (ADS)

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

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

1983-12-01

315

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

Microsoft Academic Search

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

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

1979-01-01

316

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

Microsoft Academic Search

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

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

1979-01-01

317

Thermal modeling of power gallium arsenide microwave integrated circuits  

SciTech Connect

Low-power Gallium Arsenide-based microwave circuits have been used for many years for frequencies higher than those possible with silicon technology. At the present time manufacturers are developing power devices for ever higher frequencies using GaAs MESFET's and heterojunction bipolar devices constructed with III-V compounds on GaAs substrates. There is also interest in integrating power devices on Monolithic Microwave Integrated Circuits (MMIC's). A problem with the technology is the low thermal conductivity of Gallium Arsenide and this gives rise to thermal design problems which must be solved if good reliability is to be achieved. The paper uses a three-dimensional numerical simulator to study this problem and in particular examines the approximations which are possible in performing realistic assessments of the thermal resistance of typical GaAs power device structures under steady-state conditions.

Webb, P.W. (Univ. of Birmingham, Edgbaston (United Kingdom))

1993-05-01

318

Ames Lab 101: Next Generation Power Lines  

SciTech Connect

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.

Russell, Alan

2010-01-01

319

Powerful non-thermal emission in black-hole powered sources  

NASA Astrophysics Data System (ADS)

Powerful non-thermal emission has been detected coming from relativistic collimated outflows launched in the vicinity of black holes of a very wide range of masses, from few to ~10^10 Msun. These collimated outflows or jets have large amounts of energy and momentum extracted from the black hole itself and/or from matter trapped in its potential well. The key ingredients for the formation of these powerful jets are accretion of matter with angular momentum, the huge gravitational potential of the compact object, the strong ordered magnetic fields near the black-hole horizon, the potentially large rotational energy in the case of a Kerr black hole, and an escape velocity close to c. At different scales along the outflows, i.e. ~10-10^10 RSch from the black hole, the local conditions can lead to the generation of non-thermal populations of particles via, e.g., magnetic reconnection, magneto-centrifugal mechanisms, diffusive processes, or the so-called converter mechanism. These non-thermal populations of particles, interacting with dense matter, magnetic, and radiation fields, could yield radio-to-gamma-ray emission via synchrotron process, inverse Compton scattering, relativistic Bremsstrahlung, proton-proton and photo-hadron colissions, and even heavy nuclei photo-disintegration. Other processes, like pair creation or the development of electromagnetic cascades, could be also relevant in black-hole jets and their surroundings. Black holes of different masses, accretion rates and environments show different phenomenologies, as can be observed in AGNs, GRBs or microquasars. Nonetheless, these sources basically share the same fundamental physics: accretion, black-hole rotation, plus an environment, but they are individualized due to their own specific conditions. In this paper, we qualitatively review the main characteristics of the non-thermal emission produced in jets from black holes, giving also a brief overview on the physical properties of black hole/jet systems. We comment as well on some important differences and similarities between classes of sources, and on the prospects for the study of the non-thermal emission from astrophysical sources powered by black holes.

Bosch-Ramon, V.

320

Generating Functions for the Powers of Fibonacci Sequences  

ERIC Educational Resources Information Center

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.

Terrana, D.; Chen, H.

2007-01-01

321

46 CFR 111.10-4 - Power requirements, generating sources.  

Code of Federal Regulations, 2011 CFR

...SYSTEMS-GENERAL REQUIREMENTS Power Supply § 111.10-4 Power...must be sufficient to supply those services necessary...ventilation, sanitation, and fresh water. (c) The capacity...constant-voltage generators which supply both ship's...

2011-10-01

322

46 CFR 111.10-4 - Power requirements, generating sources.  

Code of Federal Regulations, 2012 CFR

...SYSTEMS-GENERAL REQUIREMENTS Power Supply § 111.10-4 Power...must be sufficient to supply those services necessary...ventilation, sanitation, and fresh water. (c) The capacity...constant-voltage generators which supply both ship's...

2012-10-01

323

46 CFR 111.10-4 - Power requirements, generating sources.  

Code of Federal Regulations, 2013 CFR

...SYSTEMS-GENERAL REQUIREMENTS Power Supply § 111.10-4 Power...must be sufficient to supply those services necessary...ventilation, sanitation, and fresh water. (c) The capacity...constant-voltage generators which supply both ship's...

2013-10-01

324

46 CFR 111.10-4 - Power requirements, generating sources.  

Code of Federal Regulations, 2010 CFR

...SYSTEMS-GENERAL REQUIREMENTS Power Supply § 111.10-4 Power...must be sufficient to supply those services necessary...ventilation, sanitation, and fresh water. (c) The capacity...constant-voltage generators which supply both ship's...

2010-10-01

325

Science 101: How do windmills generate power?  

NSDL National Science Digital Library

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.

Robertson, William C.

2009-07-01

326

An Evolutionary Path for Concentrating Thermal Solar Power Technologies: A New Approach for Modeling CSP Power Costs and Potential  

SciTech Connect

Concentrating thermal solar power (CSP) technology is a potentially competitive power generation option, particularly in arid regions where direct sunlight is abundant. We examine the potential role of CSP power plants and their contribution to carbon emissions reduction. The answers to these questions depend on the cost of electricity generated by CSP plants. Although a few studies have projected future CSP costs based on assumptions for technology advancement and the effect of economies of scale and learning curves, few studies have considered the combined effects of intermittency, solar irradiance changes by season, and diurnal and seasonal system load changes. Because the generation of a solar plant varies over a day and by season, the interactions between CSP generators and other generators in the electric system can play an important role in determining costs. In effect, CSP electricity generation cost will depend on the CSP market penetration. This paper examines this relationship and explores possible evolutionary paths for CSP technologies with and without thermal storage.

Zhang, Yabei; Smith, Steven J.

2008-05-08

327

Thermoelectric module construction for low temperature gradient power generation  

Microsoft Academic Search

Energy related carbon dioxide emissions are the largest contributors to greenhouse gasses [1]. Thermoelectric power generation that exploits natural temperature differences between the air and earth can be a zero-emission replacement to small stand-alone power sources. Maximizing the temperature drop across the module is crucial to achieving optimal output power. An equation relating output power to thermoelectric module parameters is

Y. Meydbray; R. Singh; Ali Shakouri

2005-01-01

328

Distributed Power Generation: Requirements and Recommendations for an ICT Architecture  

E-print Network

possible to generate energy efficiently in large-scale power plants, a complex infrastructure is needed as the final storage of the conversion products in the nuclear power case imply severe environmental problems production and distribution costs [1]. Unlike consumption power, balance power is not used to operate elec

Appelrath, Hans-Jürgen

329

Spin current generated by thermally driven ultrafast demagnetization.  

PubMed

Spin current is the key element for nanoscale spintronic devices. For ultrafast operation of such nano-devices, generation of spin current in picoseconds, a timescale that is difficult to achieve using electrical circuits, is highly desired. Here we show thermally driven ultrafast demagnetization of a perpendicular ferromagnet leads to spin accumulation in a normal metal and spin transfer torque in an in-plane ferromagnet. The data are well described by models of spin generation and transport based on differences and gradients of thermodynamic parameters. The temperature difference between electrons and magnons is the driving force for spin current generation by ultrafast demagnetization. On longer timescales, a few picoseconds following laser excitation, we also observe a small contribution to spin current by a temperature gradient and the spin-dependent Seebeck effect. PMID:25007978

Choi, Gyung-Min; Min, Byoung-Chul; Lee, Kyung-Jin; Cahill, David G

2014-01-01

330

Generation of photoacoustic transients from optically induced thermal gradients.  

PubMed

Irradiation of an absorbing surface in contact with a transparent fluid with a pulsed laser can result in the generation of extremely large thermal gradients. For example, when a laser with a pulse width of 10 ns and a fluence of 1 J/cm(2) irradiates a region with an absorption of 1 cm(1) having the thermal properties of liquid water, a thermal gradient on the order of 105 K/m at the interface is produced. Here, it is shown that the effect of such thermal gradients on photoacoustic waves from an infinite half space and from a uniformly irradiated sphere is the production of fast transients on the leading edges of the waves. The character of the transients is determined from an additional source term in the wave equation for pressure that obtains when heat conduction is taken into account. Experiments are reported showing the predicted transients on photoacoustic waves from absorbing layers in contact with transparent fluids irradiated with 10 ns laser pulses. PMID:25235427

Frez, Clifford; Wu, Binbin; Diebold, Gerald

2014-04-01

331

Power Balance Theory Based Voltage and Frequency Control for IAG in Wind Power Generation  

Microsoft Academic Search

This paper deals with an application of the power balance theory in a voltage and frequency controller (VFC) of an autonomous wind power generation using an isolated asynchronous generator (IAG) feeding three-phase four wire loads. The reference generator currents are estimated using the power balance theory to control the voltage and frequency of IAG system. Three-leg voltage source converter (VSC)

Bhim Singh; Shailendra Sharma

2009-01-01

332

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

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

333

Modular Analysis of Automobile Exhaust Thermoelectric Power Generation System  

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

334

Thermal-Hydraulic Analyses of Steam Generator Tube Rupture Accident for the Kori Nuclear Unit 1 Pressurized Thermal Shock Study  

SciTech Connect

This paper discusses a thermal-hydraulic analysis methodology using RETRAN-3D and assembles system analyses for pressurized thermal shock resulting from a steam generator tube rupture accident in Kori Nuclear Unit 1. Through a systematic definition of sequences and thermal-hydraulic analyses using RETRAN-3D, the most important parameters on downcomer overcooling were identified. The break location that leads to the most significant overcooling was found to be the hot leg side in the loop that does not contain the charging flow inlet. The initial power level had a large effect on the downcomer overcooling. The closure failure of the pressurizer power operated relief valves and the termination failure of the safety injection were found to be the most significant operator actions. In contrast, auxiliary feedwater control failure had little effect on overcooling, and the steam dump valve closure failure merely resulted in a temperature rise in the latter half of the transient. Through these analyses, recommendations for sequence grouping and against downcomer overcooling are provided.

Hong, Soon-Joon [FNC Technology Company (Korea, Republic of); Kim, Jae-Hak [FNC Technology Company (Korea, Republic of); Kim, Yong-Soo [Seoul National University (Korea, Republic of); Park, Goon-Cherl [Seoul National University (Korea, Republic of)

2002-06-15

335

Neuro-Fuzzy Computational Technique to Control Load Frequency in Hydro-Thermal Interconnected Power System  

NASA Astrophysics Data System (ADS)

In this research work, two areas hydro-thermal power system connected through tie-lines is considered. The perturbation of frequencies at the areas and resulting tie line power flows arise due to unpredictable load variations that cause mismatch between the generated and demanded powers. Due to rising and falling power demand, the real and reactive power balance is harmed; hence frequency and voltage get deviated from nominal value. This necessitates designing of an accurate and fast controller to maintain the system parameters at nominal value. The main purpose of system generation control is to balance the system generation against the load and losses so that the desired frequency and power interchange between neighboring systems are maintained. The intelligent controllers like fuzzy logic, artificial neural network (ANN) and hybrid fuzzy neural network approaches are used for automatic generation control for the two area interconnected power systems. Area 1 consists of thermal reheat power plant whereas area 2 consists of hydro power plant with electric governor. Performance evaluation is carried out by using intelligent (ANFIS, ANN and fuzzy) control and conventional PI and PID control approaches. To enhance the performance of controller sliding surface i.e. variable structure control is included. The model of interconnected power system has been developed with all five types of said controllers and simulated using MATLAB/SIMULINK package. The performance of the intelligent controllers has been compared with the conventional PI and PID controllers for the interconnected power system. A comparison of ANFIS, ANN, Fuzzy and PI, PID based approaches shows the superiority of proposed ANFIS over ANN, fuzzy and PI, PID. Thus the hybrid fuzzy neural network controller has better dynamic response i.e., quick in operation, reduced error magnitude and minimized frequency transients.

Prakash, S.; Sinha, S. K.

2014-08-01

336

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

SciTech Connect

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)

Not Available

1980-06-01

337

Investigation and study on compressed air storage power generation system, part 2  

NASA Astrophysics Data System (ADS)

Compressed air storage power generation system (CAES) was studied. As a system for response to peak loads, both output and efficiency were better than those of the previous year due to the study on the temperature of the turbine's inlet. As a system for response to peak and middle loads, steam power generation, which makes use of exhaust heat from the aftercooler and the low pressure turbine's outlet, was integrated into the system, and its heat efficiency was better than that of the usual thermal power generation. However, it is inferior to the latest LNG combined cycle power generation and it does not appeal much as a middle load power source. Deformation strength characteristics of the underground cavity rocks were clarified, and a multi-structure lining method was suggested. Its location area is restricted by the layer distribution. Construction cost per kW is 220,000 yen, and the power generation prime cost is a little higher than that of pumped storage power generation. As a pumped storage power station has difficulty in finding suitable location and is higher in costs, CAES can be put into existence as a system for response to peak loads in view of economy in the future.

1989-03-01

338

Thermal management system options for high power space platforms  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

339

Piezoelectric Generator for Powering Remote Sensing Networks  

E-print Network

This paper deals with the design, modeling and experimental validation of a piezoelectric “harvest ” ambient energy generator based on ambient vibrations to be used in remote and long-term sensing networks. Simulations and experimental studies validate the functionality of individual components in an integrated piezoelectric generator unit.

unknown authors

340

Local Control of Reactive Power by Distributed Photovoltaic Generators  

Microsoft Academic Search

High penetration levels of distributed photovoltaic (PV) generation on an electrical distribution circuit may 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. Fast-reacting, VAR-capable PV inverters may provide the necessary reactive power injection or consumption to maintain voltage

Konstantin S. Turitsyn; Petr Sulc; Scott Backhaus; Misha Chertkov

2010-01-01

341

DOWNHOLE POWER GENERATION AND WIRELESS COMMUNICATIONS FOR INTELLIGENT COMPLETIONS APPLICATIONS  

SciTech Connect

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.

Paul Tubel

2004-02-01

342

Solar energy prospects for electric power generation in Brazil  

Microsoft Academic Search

A review of the energy prospects for electric power generation in Brazil indicates that hydraulic resources offer the best possibilities. However, Brazil's hydroelectric potential, both known and assumed, lies in the north, which is far away from the country's developed centers and where settlement is difficult. Exploitation of other resources for electric power generation is necessary before 1990. The discussion

D. Magnoli

1976-01-01

343

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER  

Microsoft Academic Search

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

LC BROWN; GE BESENBRUCH; KR SCHULTZ; JF FUNK; PS PICKARD; AC MARSHALL; SK SHOWALTER

2003-01-01

344

Remote-site power generation opportunities for Alaska  

Microsoft Academic Search

The Energy and Environmental Research Center (EERC) has been working with the Federal Energy Technology Center in Morgantown, West Virginia, to assess options for small, low-cost, environmental acceptable power generation for application in remote areas of Alaska. The goal of this activity was to reduce the use of fuel in Alaskan villages by developing small, low-cost power generation applications. Because

1997-01-01

345

Opening New Frontiers in Power Generation  

E-print Network

#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

Haile, Sossina M.

346

Nuclear power generation and fuel cycle report 1997  

SciTech Connect

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.

NONE

1997-09-01

347

Heat Transfer and Thermophotovoltaic Power Generation in Oil-fired Heating Systems  

SciTech Connect

The focus of this study is the production of electric power in an oil-fired, residential heatingsystem using thermophotovoltaic (TPV) conversion devices. This work uses experimental, computational, and analytical methods to investigate thermal mechanisms that drive electric power production in the TPV systems. An objective of this work is to produce results that will lead to the development of systems that generate enough electricity such that the boiler is self-powering. An important design constraint employed in this investigation is the use of conventional, yellow-flame oil burners, integrated with a typical boiler. The power production target for the systems developed here is 100 W - the power requirement for a boiler that uses low-power auxiliary components. The important heattransfer coupling mechanisms that drive power production in the systems studied are discussed. The results of this work may lead to the development of systems that export power to the home electric system.

Butcher, T.; Hammonds, J.S.; Horne, E.; Kamath, B.; Carpenter, J.; Woods, D.R.

2010-10-21

348

Wind power generation and dispatch in competitive power markets  

Microsoft Academic Search

Wind energy is currently the fastest growing type of renewable energy. The main motivation is led by more strict emission constraints and higher fuel prices. In addition, recent developments in wind turbine technology and financial incentives have made wind energy technically and economically viable almost anywhere. In restructured power systems, reliable and economical operation of power systems are the two

Lisias Abreu

2008-01-01

349

Two dimensional thermal and charge mapping of power thyristors  

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

350

Thermal improvements for high power UV LED clusters  

Microsoft Academic Search

We present a high power density UV LED module for a wavelength of 395 nm with an optical power density of 27.3 W\\/cm 2 . The module consists of 98 densely packed LED chips soldered onto an Al2O3 ceramic board. Thermal and optical measurements were conducted. The module was cooled by a forced air heat sink for the characterization experiments.

Marc Schneider; Benjamin Leyrer; Christian Herbold; Klaus Trampert; Jurgen J. Brandner

2011-01-01

351

Prognostics approach for power MOSFET under thermal-stress aging  

Microsoft Academic Search

The prognostic technique for a power MOSFET presented in this paper is based on accelerated aging of MOSFET IRF520Npbf in a TO-220 package. The methodology utilizes thermal and power cycling to accelerate the life of the devices. The major failure mechanism for the stress conditions is die-attachment degradation, typical for discrete devices with lead-free solder die attachment. It has been

Jose R. Celaya; Abhinav Saxena; Chetan S. Kulkarni; Sankalita Saha; Kai Goebel

2012-01-01

352

Thermal power terms in the Einstein-dilaton system  

E-print Network

We employ the gauge/string duality to study the thermal power terms of various thermodynamic quantities in gauge theories and the renormalized Polyakov loop above the deconfinement phase transition. We restrict ourselves to the five-dimensional Einstein gravity coupled to a single scalar, the dilaton. The asymptotic solutions of the system for a general dilaton potential are employed to study the power contributions of various quantities. If the dilaton is dual to the dimension-4 operator ${\\rm Tr} F_{\\mu\

Zuo, Fen

2014-01-01

353

Thermal power terms in the Einstein-dilaton system  

E-print Network

We employ the gauge/string duality to study the thermal power terms of various thermodynamic quantities in gauge theories and the renormalized Polyakov loop above the deconfinement phase transition. We restrict ourselves to the five-dimensional Einstein gravity coupled to a single scalar, the dilaton. The asymptotic solutions of the system for a general dilaton potential are employed to study the power contributions of various quantities. If the dilaton is dual to the dimension-4 operator ${\\rm Tr} F_{\\mu\

Fen Zuo

2014-04-17

354

Propellant-powered actuator for gas generators  

NASA Technical Reports Server (NTRS)

Hydrazine operated monopropellant generators are used for spacecraft rocket engines and propellant pressurization systems. Measured work output of monopropellant actuators compares favorably with output of squib-type actuators.

Makowski, M. J.

1972-01-01

355

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

Microsoft Academic Search

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,

Volker Quaschning

2004-01-01

356

Sizing Storage and Wind Generation Capacities in Remote Power Systems  

E-print Network

Sizing Storage and Wind Generation Capacities in Remote Power Systems by Andy Gassner B capital investment costs of renewable energy technologies. Specifically, wind power represents the most and small power systems. However, the variability due to the stochastic nature of the wind resource

Victoria, University of

357

24 DTU International Energy Report 2013 Stochastic power generation  

E-print Network

that their power output can be curtailed if necessary. Renewable energy sources such as wind, solar, wave and tidal24 DTU International Energy Report 2013 Stochastic power generation Introduction Our path towards intheformofheatandelectricity.ByJune2012,cumula- tive installed wind power capacity worldwide had reached 254

Paris-Sud XI, Université de

358

C Produced by Nuclear Power Reactors Generation and Characterization of  

E-print Network

14 C Produced by Nuclear Power Reactors ­ Generation and Characterization of Gaseous, Liquid in the terrestrial environment in the vicinity of two European nuclear power plants. Radiocarbon 46(2)863­868. III levels in the vicinity of the Lithuanian nuclear power plant Ignalina. Nuclear Instruments and Methods

Haviland, David

359

Power Generation Investments and Technology Choices under Emissions Trading  

Microsoft Academic Search

The overall purpose of this paper is to analyse how power generation technology choices will be affected by climate policy. Special attention is paid to the dissemination of renewable power technologies following climate policy initiatives in Sweden and Eastern Europe. An overall conclusion is that carbon policy will affect new investments in renewable power technologies in both Sweden and Eastern

Fredrik Pettersson

2008-01-01

360

Optimal distributed power generation under network load constraints  

E-print Network

, 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 (DPG) refers to an electric power source such as solar, wind or combined heat power (CHP) connected

Utrecht, Universiteit

361

Participation in reactive power market considering generator aging  

Microsoft Academic Search

As one of the most important ancillary services, reactive power production plays a crucial rule in power system operation, reliability and security. Because of the opportunity costs in providing reactive power, producers are under great pressure to provide VAr support. In this paper, a new challenge on the reactive capability curves (RCC) of the synchronous generator is discussed. The RCC

I. Niazy; J. Ebadi; S. Sabzevari; A. Niazy; H. Mortazavi; H. R. Poursoltani

2010-01-01

362

Micromachined CMOS thermoelectric generators as on-chip power supply  

Microsoft Academic Search

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

M. Strasser; R. Aigner; C. Lauterbach; T. F. Sturm; M. Franosch; G. Wachutka

2004-01-01

363

Optical fiber instrumentation of a high power generator and turbine  

NASA Astrophysics Data System (ADS)

The instrumentation of a high power generator and its complementary systems including the turbine bearings is presented and discussed. The generator consists of a 175MW hydroelectric generator installed in the Salto Osório power plant in the southern region of Brazil. Results show good agreement with the already existing instrumentation and demonstrate the technology potential for a full optical fiber sensing system to monitor these large machines.

da Silva, Erlon Vagner; Dreyer, Uilian José; de Morais Sousa, Kleiton; Babinski, Valderi Junot; Somenzi, Jonas; Mezzadri, Felipe; de Lourenço Junior, Ivo; Martelli, Cicero; Cardozo da Silva, Jean Carlos

2013-05-01

364

Introduction of Car Alternators for Small Scale Wind Power Generation  

Microsoft Academic Search

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

Nanayakkara D. P. N

365

Study of Thermal Control Systems for orbiting power systems  

NASA Technical Reports Server (NTRS)

Thermal control system designs were evaluated for the 25 kW power system. Factors considered include long operating life, high reliability, and meteoroid hazards to the space radiator. Based on a cost advantage, the bumpered pumped fluid radiator is recommended for the initial 25 kW power system and intermediate versions up to 50 kW. For advanced power systems with heat rejection rates above 50 kW the lower weight of the advanced heat pipe radiator offsets the higher cost and this design is recommended. The power system payloads heat rejection allocations studies show that a centralized heat rejection system is the most weight and cost effective approach. The thermal interface between the power system and the payloads was addressed and a concept for a contact heat exchanger that eliminates fluid transfer between the power system and the payloads was developed. Finally, a preliminary design of the thermal control system, with emphasis on the radiator and radiator deployment mechanism, is presented.

Howell, H. R.

1981-01-01

366

Power enhancement of heat engines via correlated thermalization in multilevel systems  

E-print Network

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.

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

2014-11-05

367

Neural-net based real-time economic dispatch for thermal power plants  

SciTech Connect

This paper proposes the application of artificial neural networks to real-time optimal generation dispatch of thermal units. The approach can take into account the operational requirements and network losses. The proposed economic dispatch uses an artificial neural network (ANN) for generation of penalty factors, depending on the input generator powers and identified system load change. Then, a few additional iterations are performed within an iterative computation procedure for the solution of coordination equations, by using reference-bus penalty-factors derived from the Newton-Raphson load flow. A coordination technique for environmental and economic dispatch of pure thermal systems, based on the neural-net theory for simplified solution algorithms and improved man-machine interface is introduced. Numerical results on two test examples show that the proposed algorithm can efficiently and accurately develop optimal and feasible generator output trajectories, by applying neural-net forecasts of system load patterns.

Djukanovic, M.; Milosevic, B. [Inst. Nikola Tesla, Belgrade (Yugoslavia). Dept. of Power Systems] [Inst. Nikola Tesla, Belgrade (Yugoslavia). Dept. of Power Systems; Calovic, M. [Univ. of Belgrade (Yugoslavia). Dept. of Electrical Engineering] [Univ. of Belgrade (Yugoslavia). Dept. of Electrical Engineering; Sobajic, D.J. [Electric Power Research Inst., Palo Alto, CA (United States)] [Electric Power Research Inst., Palo Alto, CA (United States)

1996-12-01

368

Lifetime prediction modeling of airfoils for advanced power generation  

NASA Astrophysics Data System (ADS)

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.

Karaivanov, Ventzislav Gueorguiev

369

Comparison of advanced thermal and electrical storage for parabolic dish solar thermal power systems  

Microsoft Academic Search

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,

T. Fujita; G. C. Birur; J. M. Schredder; J. M. Bowyer; H. I. Awaya

1982-01-01

370

Solar thermal power cycle with integration of methanol decomposition and middle-temperature solar thermal energy  

Microsoft Academic Search

In this paper, we have proposed a new solar thermal power cycle which integrates methanol decomposition and middle-temperature solar thermal energy, and investigated its features based on the principle of the cascade utilization of chemical exergy. Also, the methanol decomposition with a catalyst was experimentally studied at temperatures of 150–300°C and under atmospheric pressure. The chemical energy released by methanol

Hui Hong; Hongguang Jin; Jun Ji; Zhifeng Wang; Ruixian Cai

2005-01-01

371

Parabolic Dish Solar Thermal Power Annual Program Review Proceedings  

NASA Technical Reports Server (NTRS)

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.

Lucas, J. W.

1982-01-01

372

Thermal analysis of PANSAT batteries and Electrical Power Subsystem  

Microsoft Academic Search

The thermal design of a spacecraft ensures proper heat transfer so all components and subsystems remain within prescribed temperature limits during all aspects of the spacecraft's mission. This thesis develops a point to-point heat flow model of the Electrical Power Subsystem (EPS) and its associated housing for the Petite Amateur Navy Satellite (PANSAT). This analysis was performed to identify physical

Sheila A. Patterson

1994-01-01

373

Adaptive optimal control of steam temperatures for thermal power plants  

Microsoft Academic Search

An adaptive optimal control method using a process control computer was developed for boiler steam temperature control for thermal power plants. A process dynamics model, which describes the dynamic plant behavior, is used in the calculations for adaptive optimal control. The mode used is a multi-input and output ARMA (autoregressive moving-average) with parameters identified online by the Kalman filter method.

M. Nomura; Y. Sato

1989-01-01

374

Power-Delivery Networks Optimization with Thermal Reliability Integrity  

Microsoft Academic Search

With the growing power consumption in modern high per- formance VLSI designs, nonuniform temperature distribu- tion and limited heat-conduction capability have caused ther- mal induced performance and reliability degradation. Elec- tromigration is the main reliability concern and will become a more limiting factor of IC designs. It must be addressed together with a thermal reliability modeling. This issue also has

Ting-Yuan Wang; Jeng-Liang Tsai; Charlie Chung-Ping Chen

375

APPLICATIONS FOR DISPERSION-STRENGTHENED ALLOYS IN THERMAL POWER SYSTEMS  

Microsoft Academic Search

Dispersing small quantities of ceramic particles along the grain boundaries of an alloy can substantially increase its resistance to creep at high temperatures. This creep resistance, if matched with corrosion resistance, makes these alloys particularly suited for the highest-temperature applications within thermal power systems. The University of North Dakota Energy & Environmental Research Center (EERC) is working with Oak Ridge

John P. Hurley

376

Thermal spike model in the electronic stopping power regime  

Microsoft Academic Search

Two models have been proposed in order to explain the appearance of latent tracks induced in matter by the slowing down process of ions in the electronic stopping power regime. The first one was the thermal spike proposed by Desauer and reconsidered for metals by Seitz and Koehler. The second one was the ionic spike proposed by Fleischer et al

M. Toulemonde; E. Paumier; C. Dufour

1993-01-01

377

Protective, Modular Wave Power Generation System  

SciTech Connect

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.

Vvedensky, Jane M.; Park, Robert Y.

2012-11-27

378

Safe Operation of Backup Power Generators  

E-print Network

is improperly sealed, invisible fuel vapors from the container can move along the ground and be ignited by the water heater?s pilot flame. ? Turn the generator off and let it cool before refu- eling. A gasoline spill on hot engine parts could ignite... is improperly sealed, invisible fuel vapors from the container can move along the ground and be ignited by the water heater?s pilot flame. ? Turn the generator off and let it cool before refu- eling. A gasoline spill on hot engine parts could ignite...

Smith, David

2006-04-19

379

Thermal analysis of PANSAT batteries and Electrical Power Subsystem  

NASA Astrophysics Data System (ADS)

The thermal design of a spacecraft ensures proper heat transfer so all components and subsystems remain within prescribed temperature limits during all aspects of the spacecraft's mission. This thesis develops a point to-point heat flow model of the Electrical Power Subsystem (EPS) and its associated housing for the Petite Amateur Navy Satellite (PANSAT). This analysis was performed to identify physical locations in the EPS where temperatures may exceed the limits established to protect sensitive electronic components, and to define the expected environment of the batteries. The Integrated Thermal Analysis System (ITAS) and a Steady State Thermal Analyzer and Model Builder were used to perform steady state and transient analyses on the EPS: analysis of the batteries was performed using ITAS only. The simulated transient temperatures within the EPS housing remained within limits, but the batteries exceeded specifications. It is suggested that a passive thermal control technique be adapted for the batteries and its design be experimentally validated before flight.

Patterson, Sheila A.

1994-09-01

380

Powering a Generation of Change: A Smithsonian Documentation Project  

NSDL National Science Digital Library

Powering a Generation of Change is a Smithsonian Institution documentation project that is a response to the coming deregulation of the electric power industry in the United States and Canada. The site is interesting almost as much for its information on electricity and the history of electric power regulation, as for its information explaining deregulation and its societal impacts. One of the highlights of the site is the Visions of Power section, with in-depth interviews with Joseph P. Kearney of US Generating, Andre Caille of Hydro-Quebec, and William T. McCormick, Jr. of CMS Energy. Visions of Power offers numerous links to information provided by a variety of participants in the deregulation debate. The Powering the Past section provides a fascinating tour through the history of electric power, accompanied by images from various Smithsonian museums. A large bibliography on electric power is also available.

1997-01-01

381

Siting Power Generation Facilities: Environmental Justice Concerns  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) provides this PowerPoint document on environmental justice concerns. The document includes ten classroom activities on related topics such as participatory mapping, energy consumption and demographics. Worksheets are included in the document. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

Crawford, Charles; Hlebakos, Jason; Pichette, Claire

2011-06-10

382

Power generation potential of biomass gasification systems  

Microsoft Academic Search

Biomass has the potential to contribute a significant portion of the electricity consumed in industrialized nations and a major share of the power mix in developing countries. In addition to providing an alternative to fossil-fuel-based energy and creating new markets for agriculture, a renewable resource like biomass used in a sustainable fashion facilitates closure of the carbon cycle. To realize

Charles M. Kinoshita; Scott Q. Turn; Ralph P. Overend; Richard L. Bain

1997-01-01

383

Geothermal power generation using the binary cycle  

Microsoft Academic Search

Geothermal resources of the world are comparable in magnitude to fossil ; fuel and nuclear energy resources. It is evident that the technology exists to ; exploit economically many of the world's known geothermal reservoirs and that the ; impact on the environment will be minimal. A flowsheet for a typical binary ; power cycle is shown. The geothermal fluid

B. Holt; A. J. L. Hutchinson; D. S. Cortez

1973-01-01

384

Coupling an induction motor type generator to ac power lines. [making windmill generators compatible with public power lines  

NASA Technical Reports Server (NTRS)

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.

Nola, F. J. (inventor)

1984-01-01

385

The Meteosat Second Generation (MSG) power system  

Microsoft Academic Search

Under the direction of the European Meteorological Satellite Organisation (EUMETSAT) and the European Space Agency (ESA), space industries within Europe are in the process of developing a new series of larger and more performant geostationary weather satellites. The initial three spacecraft within this new series, which are known by the name of Meteosat Second Generation (MSG), are due to be

J. E. Haines; D. Levins; A. Robben; A. Sepers

1997-01-01

386

New loads for pulse power generators  

Microsoft Academic Search

Cylindrical wire array implosion, successively used at the Z generator of Sandia Labs., is suggested for application to current switching in the 10 ns range on the load disposed in different cavity. This inductive switch can be used for the fast implosion of the cylindrical wire array in order obtain X-ray pulses in the 10 keV range. Sharpened current pulses

L. I. Rudakov

1999-01-01

387

Sustainable wind powered generation and utilization for West Africa  

SciTech Connect

Due to the poor economic situations in several West African countries, the existing electrical and mechanical engineering power generating systems cannot be properly maintained. The existing power generating systems have been working at very poor efficiencies and poor levels of reliability. Engineering infra-structures, particularly for the rural areas, cannot function properly because of the poor reliability of the existing power generating systems. In order to provide effective solutions to this problem, the use of wind powered systems is being recommended for West African countries and possibly other countries where fairly constant high wind speeds are available. The results of the technical investigations carried out during the last thirty years, in order to provide alternative wind powered generating systems, and which are easier to maintain than the existing power generating systems, together with the engineering applications of the wind powered systems, for small scale water supply and electrical power generating systems for homes and rural areas; will be highlighted and discussed in this paper.

Soboyejo, A.B.O. [Ohio State Univ., Columbus, OH (United States)

1997-09-01

388

Effect of thermal power plant emissions on Catharanthus roseus L  

SciTech Connect

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.

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

389

Feasibility of the inflow disk generator for open-cycle MHD power generation  

NASA Astrophysics Data System (ADS)

A feasibility study of the inflow disk MHD generator for baseload applications was performed. Each design element, i.e., the combustor, the inlet flow path, the generator channel, the diffuser and the magnet, was studied in detail in order to provide a comprehensive assessment of the inflow disk generator. Based on these results, the performance of the inflow disk generator was calculated for two different thermal inputs: 1250 MW(th) and 2500 MW(th). It was shown that the performance of the inflow disk generator is similar to that of the diagonal generator within the uncertainty of the analysis.

Nakamura, T.; Lear, W. E.; Eustis, R. H.

1981-01-01

390

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

NASA Technical Reports Server (NTRS)

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.

Cherry, W. R.

1971-01-01

391

Alternative power generation concepts for space  

NASA Astrophysics Data System (ADS)

Trade and optimization studies that highlight the potential of solar and nuclear dynamic systems relative to photovoltaic power systems are summarized. The solar dynamic case is the LEO Stirling system, while the nuclear system is the SP-100 system goal. Nuclear systems have the potential for the lightest weight, least area, sunlight independent, radiation-durable system. Solar dynamic systems pose a stiff challenge to photovoltaic systems in the midaltitudes because of their insensitivity to the Van Allen radiation belts. While the initial operational capability space station power system is only slightly superior to the SOA PV system, with development focused on the key technologies, advanced solar dynamic systems are fully competitive in LEO midaltitudes with the advanced photovoltaic systems. Advances in energy storage systems (100 Whrs/kg required) are essential.

Brandhorst, Henry W., Jr.; Juhasz, Albert J.; Jones, Barbara I.

1986-11-01

392

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

NASA Technical Reports Server (NTRS)

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.

Steele, H. L.; Wen, L.

1981-01-01

393

Power generating system and method utilizing hydropyrolysis  

DOEpatents

A vapor transmission cycle is described which burns a slurry of coal and water with some of the air from the gas turbine compressor, cools and cleans the resulting low-Btu fuel gas, burns the clean fuel gas with the remaining air from the compressor, and extracts the available energy in the gas turbine. The cycle lends itself to combined-cycle cogeneration for the production of steam, absorption cooling, and electric power.

Tolman, R.

1986-12-30

394

Solar powered Stirling cycle electrical generator  

NASA Technical Reports Server (NTRS)

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. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, non-contacting gas bearings, and can be hermetically sealed. These attributes of the free-piston Stirling engine also make it a viable candidate for terrestrial applications. In cooperation with the Department of Energy, system designs are currently being completed that feature the free-piston Stirling engine for terrestrial applications. Industry teams were assembled and are currently completing designs for two Advanced Stirling Conversion Systems utilizing technology being developed under the NASA CSTI Program. These systems, when coupled with a parabolic mirror to collect the solar energy, are capable of producing about 25 kW of electricity to a utility grid. Industry has identified a niche market for dish Stirling systems for worldwide remote power application. They believe that these niche markets may play a major role in the introduction of Stirling products into the commercial market.

Shaltens, Richard K.

1991-01-01

395

Thermocline Thermal Storage Test for Large-Scale Solar Thermal Power Plants  

SciTech Connect

Solar thermal-to-electric power plants have been tested and investigated at Sandia National Laboratories (SNL) since the late 1970s, and thermal storage has always been an area of key study because it affords an economical method of delivering solar-electricity during non-daylight hours. This paper describes the design considerations of a new, single-tank, thermal storage system and details the benefits of employing this technology in large-scale (10MW to 100MW) solar thermal power plants. Since December 1999, solar engineers at Sandia National Laboratories' National Solar Thermal Test Facility (NSTTF) have designed and are constructing a thermal storage test called the thermocline system. This technology, which employs a single thermocline tank, has the potential to replace the traditional and more expensive two-tank storage systems. The thermocline tank approach uses a mixture of silica sand and quartzite rock to displace a significant portion of the volume in the tank. Then it is filled with the heat transfer fluid, a molten nitrate salt. A thermal gradient separates the hot and cold salt. Loading the tank with the combination of sand, rock, and molten salt instead of just molten salt dramatically reduces the system cost. The typical cost of the molten nitrate salt is $800 per ton versus the cost of the sand and rock portion at $70 per ton. Construction of the thermocline system will be completed in August 2000, and testing will run for two to three months. The testing results will be used to determine the economic viability of the single-tank (thermocline) storage technology for large-scale solar thermal power plants. Also discussed in this paper are the safety issues involving molten nitrate salts and other heat transfer fluids, such as synthetic heat transfer oils, and the impact of these issues on the system design.

ST.LAURENT,STEVEN J.

2000-08-14

396

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

NASA Astrophysics Data System (ADS)

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 connection of an ORC-process to following plants were investigated; a gas burning heat-only boiler, a solid fuel boiler, a steam and gas turbine (co-generation) unit, a steam turbine and a heating reactor. In each case the following economical factors for adding an ORC-process were calculated; the cost for electricity, the return of investment (ROI) and the pay-back period. The most favorable cases to utilize an ORC-process are a heating reactor, a steam turbine and a gas turbine based co-generation plant. In connection with heat-only plants a better economy were achieved than with co-generation plants. The results indicate that there can be found economically promising applications for ORC-processes in industry and power plants. It is evident that those cases should be investigated more in detail. ORC-processes allow power generation in new circumstances and can increase the efficiency of power plants. More emphasis should be paid for the R and D of this relatively new technology.

Huovilainen, Reino; Alamaeki, Jarmo; Tarjanne, Risto

397

Automatic steam generator feedwater control over full power range  

SciTech Connect

This patent describes a pressurized water nuclear reactor stream supply system having a recirculation type steam generator including a variable speed feedwater pump, a main feedwater valve and a bypass feedwater valve, a method for controlling the water level in the steam generator comprising: measuring the steam flow out of the steam generator and generating a steam flow signal commensurate with the steam flow; measuring the feedwater flow into the steam generator and generating a feedwater flow signal commensurate with the feedwater flow; measuring the water level in the steam generator and generating a water level signal commensurate with the water level; measuring the reactor power and generating a power signal commensurate with the reactor power; passing the water level signal through a first adaptive network, wherein the control coefficients in the first network have a functional form dependent on the power signal, the output of the first network representing a dynamically compensated level signal; comprising the steam flow signal with the feedwater flow signal and passing the difference through a first proportional/integral circuit to generate a compensated flow error signal.

Singh, G.; French, C.T.

1988-10-11

398

Novel deep UV photoresist with thermally crosslinkable photoacid generator  

NASA Astrophysics Data System (ADS)

The present authors have studied a novel system of deep UV photoresist based on thermally crosslinkable photoacid generators(TCL-PAG), which have two or three crosslinking groups on the same molecule that can be crosslinked to a binder resin of chemically modified poly (p-hydroxystyrene), referred to as PHST hereinafter, in the stage of prebaking via the reaction of their phenolic hydroxyl groups on the polymer chain with the crosslinking groups of TCL-PAG. Upon exposure and subsequent PEB, the crosslinkage with acetal structures is cleaved by photogenerated acids to give an unprotected phenol resin, alcohol and acetaldehyde. We investigated some structural effects on resolution, photospeed, line edge roughness and other functional properties of the resulting resists with different size of the protecting groups in a combination with different types of PAGs and bases added. KrF steppers of Nikon (NA:0.45) and ASML(NA:0.7) were used in the lithographic test with binary test masks. Various types of partially protected PHST derivatives were synthesized with different protecting groups to control the dissolution rate and the activation energy of the base resins. The resist pattern quality can be enhanced by using our new PAG system based on the thermal crosslinking mechanism. A combination of the acetal and carbonate protecting groups onto the PHS base resin with the TCL-PAG can also enhance the resist performance so that a minimum resolution of 130 nm with KrF exposure could be obtained.

Noh, Chang-Ho; Lee, Sang-Kyun; Moon, Bongsuk; Honda, Kenji

2001-08-01

399

Influence of thermal environment on optimal working conditions of thermoelectric generators  

NASA Astrophysics Data System (ADS)

Optimization analysis of thermoelectric generators operation is of importance both for practical applications and theoretical considerations. Depending on the desired goal, two different strategies are possible to achieve high performance: through optimization one may seek either power output maximization or conversion efficiency maximization. Recent literature reveals the persistent flawed notion that these two optimal working conditions may be achieved simultaneously. In this article, we lift all source of confusion by correctly posing the problem and solving it. We assume and discuss two possibilities for the environment of the generator to govern its operation: constant incoming heat flux, and constant temperature difference between the heat reservoirs. We demonstrate that, while power and efficiency are maximized simultaneously if the first assumption is considered, this is not possible with the second assumption. This latter corresponds to the seminal analyses of Ioffe who put forth and stressed the importance of the thermoelectric figure of merit ZT. We also provide a simple procedure to determine the different optimal design parameters of a thermoelectric generator connected to heat reservoirs through thermal contacts with a finite and fixed thermal conductance.

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

2014-10-01

400

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

NASA Technical Reports Server (NTRS)

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.

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

2014-01-01

401

Pressurized circulating fluidized-bed combustion for power generation  

SciTech Connect

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.

Weimer, R.F.

1995-08-01

402

Low-Power Maximum Power Point Tracker with Digital Control for Thermophotovoltaic Generators  

E-print Network

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 ...

Pilawa, Robert

403

Self-powered wireless sensor system using MEMS piezoelectric micro power generator (PMPG)  

E-print Network

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 ...

Xia, YuXin, M.B.A. Sloan School of Management.

2006-01-01

404

In Hot Water: Thermoelectric Power and Thermal Pollution  

NASA Astrophysics Data System (ADS)

The use of surface water for thermoelectric power plant cooling significantly impacts river water temperatures, posing risks to aquatic ecosystems. In addition, surface water temperatures in summer can exceed limits for power plant compliance with thermal effluent limitations, jeopardizing energy security during periods of peak power demand. For example, Brown's Ferry Nuclear Plant in Alabama curtailed power production by 50% for over 40 days in July-August of 2010 when river temperatures exceeded 90°F. Future increases in surface water temperatures due to climate change may further endanger energy security. This study examines summer intake and outflow water temperature data reported by power plants during peak production months across the United States to determine the impact of thermoelectric power plants on surface water temperatures in the summer. Initial results indicate that U.S. coal plants (n= 625) raised water temperatures by an average of 17°F (± 12°F) and discharged cooling water with median peak temperatures of 100°F (± 13°F) in the summer of 2005, the last year when this data was reliably reported. Further analysis will extend the time period of this study from 2000-2005 and expand the scope to various energy sources and cooling technologies. In addition, we explore regional variation to assess the relative threat that thermal pollution poses to energy security across the U.S.

Madden, N. T.

2010-12-01

405

ePOWER Seminar AC solar cells: A new breed of PV power generation  

E-print Network

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

Abolmaesumi, Purang

406

Power density distribution and associated thermal analysis of an elliptical polarizing undulator  

NASA Astrophysics Data System (ADS)

The Taiwan Photon Source (TPS) project is planning to construct a third-generation synchrotron accelerator in Taiwan. This 3 GeV, 500 mA high-energy accelerator will support 20 beamlines for insertion devices (ID) and 24 beamlines for bending magnets (BM). We will undertake an in-depth investigation of the power density distribution and thermal analysis of the accelerator as an important part in the design of the photon absorbers, masks, and mirrors at the front end and in the beamline areas. An elliptically polarizing undulator (EPU) will be one of the primary ID sources for this accelerator and will have a different power density distribution from the other sources. We have derived a general elliptical polarizing EPU power density distribution for this source and have performed a mathematical approximation suitable for practical engineering applications. We will also present a thermal analysis of the helical undulator using Gaussian and unit step-function approximations.

Sheng, I. C.; Kuan, C. K.

2011-04-01

407

APPLICATION OF MEMBRANE TECHNOLOGY TO POWER GENERATION WATERS  

EPA Science Inventory

Three membrane technlogies (reverse osmosis, ultrafiltration, and electrodialysis) for wastewater treatment and reuse at electric generating power plants were examined. Recirculating condenser water, ash sluice water, coal pile drainage, boiler blowdown and makeup treatment waste...

408

Risk Framework for the Next Generation Nuclear Power Plant Construction  

E-print Network

sector projects, and recently elevated to Best Practice status. However, its current format is inadequate to address the unique challenges of constructing the next generation of nuclear power plants (NPP). To understand and determine the risks...

Yeon, Jaeheum 1981-

2012-12-11

409

Improving heat capture for power generation in coal gasification plants  

E-print Network

Improving the steam cycle design to maximize power generation is demonstrated using pinch analysis targeting techniques. Previous work models the steam pressure level in composite curves based on its saturation temperature ...

Botros, Barbara Brenda

2011-01-01

410

A power conditioning system for radioisotope thermoelectric generator energy sources  

NASA Technical Reports Server (NTRS)

The use of radioisotope thermoelectric generators (RTG) as the primary source of energy in unmanned spacecraft is discussed. RTG output control, power conditioning system requirements, the electrical design, and circuit performance are also discussed.

Gillis, J. A., Jr.

1974-01-01

411

Integration of decentralized generators with the electric power grid  

E-print Network

This report develops a new methodology for studying the economic interaction of customer-owned electrical generators with the central electric power grid. The purpose of the report is to study the reciprocal effects of the ...

Finger, Susan

1981-01-01

412

Improvement of regulatory documents on decommissioning power-generating units of nuclear power plants  

Microsoft Academic Search

Approaches to revising the documentation regulating the safety of decommissioning power-generating units of nuclear power\\u000a plants are examined. It is proposed that the concept of planning decommissioning for operating and newly designed power-generating\\u000a units of nuclear power plants at all stages of their lifecycle be introduced into the analysis. It is shown that the sections\\u000a concerning the decommissioning of the

B. K. Bylkin; K. A. Gorelov; I. A. Engovatov; A. N. Zaitsev; V. K. Zimin; A. I. Musorin; P. M. Rubtsov; G. N. Nozdrin

2009-01-01

413

Use of Carbon Capture Storage Technique for Clean Power Generation  

E-print Network

Abstract- Global demand for energy shows no signs of slowing, carbon dioxide emissions keep surging to new records. More than ever, the need for a fundamental shift to a cleaner and more reliable energy system is clear. The technologies with the greatest potential for energy and carbon dioxide (CO2) emission reduction, however, are making the slowest progress. Carbon capture and storage (CCS) is not seeing the necessary rates of investment into full-scale demonstration projects and nearly onehalf of new coal-fired power plants are still being built with inefficient technology. The power generation sector is expected to contribute more than one-third of potential CO2 emissions reductions worldwide by 2020 under the 2DS, and almost 40 % of 2050 emission reduction. Enhanced power generation efficiency, a switch to lower-carbon fossil fuels, increased use of renewable and nuclear power, and the introduction of CCS are all required to achieve cleaner power generation. T I.

Mr. Pramod Chavate

414

Green supply chain management, reverse logistics and nuclear power generation  

Microsoft Academic Search

Built on the concepts of green supply chain management (G-SCM), this paper presents a multi-objective optimization programming approach to address the issue of nuclear power generation. In this study, a linear multi-objective optimization model is formulated to optimize the operations of both the nuclear power generation and the corresponding induced-waste reverse logistics. Factors such as the operational risks induced in

Jiuh-Biing Sheu

2008-01-01

415

Transportable high-energy high-power generator  

Microsoft Academic Search

High-power applications sometimes require a transportable, simple, and robust gigawatt pulsed power generator, and an analysis of various possible approaches shows that one based on a twin exploding wire array is extremely advantageous. A generator based on this technology and used with a high-energy capacitor bank has recently been developed at Loughborough University. An H-configuration circuit is used, with one

B. M. Novac; I. R. Smith; P. Senior; M. Parker; G. Louverdis

2010-01-01

416

Multi-Area Power Generation Dispatch in Competitive Markets  

Microsoft Academic Search

In competitive electric energy markets, the power generation dispatch optimization is one of the most important missions among generation companies-how to respond to the markets, dispatch their units, and maximize profits. This paper proposes an approach to incorporate power contracts, which include call and put options, forward contracts, and reliability must-run contracts, into multi-area unit commitment and economic dispatch solutions.

Chitra Yingvivatanapong; Lee Wei-Jen; Edwin Liu

2008-01-01

417

Radio Point Sources and the Thermal SZ Power Spectrum  

E-print Network

Radio point sources are strongly correlated with clusters of galaxies, so a significant fraction of the thermal Sunyaev-Zel'dovich (SZ) effect signal could be affected by point source contamination. Based on empirical estimates of the radio galaxy population, it is shown that the rms temperature fluctuations of the thermal SZ effect could be underestimated by as much as 30% at an observing frequency of 30 GHz at l>1000. The effect is larger at higher multipoles. If the recent report of excess power at small angular scales is to be explained by the thermal SZ effect, then radio point sources at an observing frequency of 30 GHz must be a surprisingly weak contaminant of the SZ effect for low-mass clusters.

Gilbert P. Holder

2002-05-27

418

Regolith thermal energy storage for lunar nighttime power  

NASA Technical Reports Server (NTRS)

A scheme for providing nighttime electric power to a lunar base is described. This scheme stores thermal energy in a pile of regolith. Any such scheme must somehow improve on the poor thermal conductivity of lunar regolith in vacuum. Two previous schemes accomplish this by casting or melting the regolith. The scheme described here wraps the regolith in a gas-tight bag and introduces a light gas to enhance thermal conductivity. This allows the system to be assembled with less energy and equipment than schemes which require melting of regolith. A point design based on the new scheme is presented. Its mass from Earth compares favorably with the mass of a regenerative fuel cell of equal capacity.

Tillotson, Brian

1992-01-01

419

On the safety to solar electric power generation  

Microsoft Academic Search

A series of studies were undertaken to assess the safety hazards in proposed solar thermal power systems (STPS). Among the risks identified are distributed heliostat defocussing, interruption of working fluid flow, receiver meltdown, and leakage of hazardous fluids. It is concluded that unique hazards are presented by sensible heat, latent heat, and thermochemical energy storage systems, although specific sources of

A. Z. Ullman; B. B. Sokolow; L. Libby; J. Daniels; J. Hill; R. Hudson; P. Hurt; A. Kashani; G. Meunier; P. Parekh

1980-01-01

420

The Environmental Impact of Electrical Power Generation: Nuclear and Fossil.  

ERIC Educational Resources Information Center

This text was written to accompany a course concerning the need, environmental costs, and benefits of electrical power generation. It was compiled and written by a committee drawn from educators, health physicists, members of industry and conservation groups, and environmental scientists. Topics include: the increasing need for electrical power

Pennsylvania State Dept. of Education, Harrisburg.

421

Development of the Power Generator for Series Hybrid Electric Vehicle  

Microsoft Academic Search

The goals for the SHEV (series hybrid electric vehicle) such as transit bus and truck are to achieve increased fuel economy, while reducing emissions and maintaining the functionally of the heavy duty vehicle. The power generator is used as an important component of backup power systems in a series hybrid system which is one type of electric hybrid propulsion systems

U. D. Choi; K. T. Kim; Y. N. Kim; S. H. Kwak; K. M. Kim; S. D. Lee; S. J. Jang; K. Becksteard

2006-01-01

422

Power Supply Generation in CMOS Passive UHF RFID Tags  

Microsoft Academic Search

The paper discusses the design of a power generation circuit suitable to provide the supply voltage for a passive UHF RFID tag. The proposed differential rectifier exhibits a low activation threshold and is compatible with digital CMOS technologies. The chip supply voltage is obtained through a Dickson-based voltage multiplier and an ultra low-power voltage regulator

Alessio Facen; A. Boni

2006-01-01

423

A New Controller Scheme for Photovoltaics Power Generation Systems  

Microsoft Academic Search

This paper presents a new controller scheme for photovoltaic (PV) power generation systems. The proposed PV controller scheme controls both the boost converter and the battery charger by using a microcontroller in order to extract maximum power from the PV array and control the charging process of the battery. The objective of the paper is to present a cost effective

Tamer T. N. Khatib; Azah Mohamed; Nowshad Amin

424

The critical power to maintain thermally stable molecular junctions  

NASA Astrophysics Data System (ADS)

With the rise of atomic-scale devices such as molecular electronics and scanning probe microscopies, energy transport processes through molecular junctions have attracted notable research interest recently. In this work, heat dissipation and transport across diamond/benzene/diamond molecular junctions are explored by performing atomistic simulations. We identify the critical power Pcr to maintain thermal stability of the junction through efficient dissipation of local heat. We also find that the molecule-probe contact features a power-dependent interfacial thermal resistance RK in the order of 109?kW-1. Moreover, both Pcr and RK display explicit dependence on atomic structures of the junction, force and temperature. For instance, Pcr can be elevated in multiple-molecule junctions, and streching the junction enhances RK by a factor of 2. The applications of these findings in molecular electronics and scanning probing measurements are discussed, providing practical guidelines in their rational design.

Wang, Yanlei; Xu, Zhiping

2014-07-01

425

Analyses of MTI Imagery of Power Plant Thermal Discharge  

SciTech Connect

MTI images of thermal discharge from three power plants are analyzed in this paper with the aid of a 3-D hydrodynamic code. The power plants use different methods to dissipate waste heat in the environment: a cooling lake at Comanche Peak, ocean discharge at Pilgrim and cooling canals at Turkey Point. This paper shows that it is possible to reproduce the temperature distributions captured in MTI imagery with accurate code inputs, but the key parameters change from site to site. Wind direction and speed are the most important parameters at Pilgrim, whereas air temperatures and dewpoint temperatures are most important at Comanche Peak and Turkey Point. This paper also shows how the combination of high-resolution thermal imagery and hydrodynamic simulation lead to better understanding of the mechanisms by which waste heat is dissipated in the environment.

Garrett, A.J.

2001-06-27

426

Analyses of MTI imagery of power plant thermal discharge  

NASA Astrophysics Data System (ADS)

MTI images of thermal discharge from three power plants are analyzed in this paper with the aid of a 3_D hydrodynamic code. The power plants use different methods to dissipate waste heat in the environment: a cooling lake at Comanche Peak, ocean discharge at Pilgrim and cooling canals at Turkey Point. This paper show s that it is possible to reproduce the temperature distributions captured in MTI imagery with accurate code inputs, but the key parameters change from site to site. Wind direction and speed are the most important parameters at Pilgrim, whereas air temperatures are most important at Comanche Peak and Turkey Point. This paper also shows how the combination of high- resolution thermal imagery and hydrodynamic simulation lead to better understanding of the mechanisms by which waste heat is dissipated in the environment.

Garrett, Alfred J.

2002-01-01

427

Cost-efficiency trade-off and the design of thermoelectric power generators.  

PubMed

The energy conversion efficiency of today's thermoelectric generators is significantly lower than that of conventional mechanical engines. Almost all of the existing research is focused on materials to improve the conversion efficiency. Here we propose a general framework to study the cost-efficiency trade-off for thermoelectric power generation. A key factor is the optimization of thermoelectric modules together with their heat source and heat sinks. Full electrical and thermal co-optimization yield a simple analytical expression for optimum design. Based on this model, power output per unit mass can be maximized. We show that the fractional area coverage of thermoelectric elements in a module could play a significant role in reducing the cost of power generation systems. PMID:21793542

Yazawa, Kazuaki; Shakouri, Ali

2011-09-01

428

Thermal energy storage units for solar electric power plants  

NASA Astrophysics Data System (ADS)

Several types of heat storage units for solar power plants with thermodynamic cycles of energy conversion are examined, including specific-heat units (particularly water-vapor devices), thermochemical units, and phase-change units. The dependence of specific capital costs for heat storage units upon time of operation is discussed, and particular consideration is give to types of connections of specific-heat units into the thermal circuit of a power plant, and to a phase-change unit that uses a heat pipe for internal heat transport.

Gudkov, V. I.; Chakalev, K. N.

429

Thermally tunable silicon racetrack resonators with ultralow tuning power.  

PubMed

We present thermally tunable silicon racetrack resonators with an ultralow tuning power of 2.4 mW per free spectral range. The use of free-standing silicon racetrack resonators with undercut structures significantly enhances the tuning efficiency, with one order of magnitude improvement of that for previously demonstrated thermo-optic devices without undercuts. The 10%-90% switching time is demonstrated to be ~170 µs. Such low-power tunable micro-resonators are particularly useful as multiplexing devices and wavelength-tunable silicon microcavity modulators. PMID:20940921

Dong, Po; Qian, Wei; Liang, Hong; Shafiiha, Roshanak; Feng, Dazeng; Li, Guoliang; Cunningham, John E; Krishnamoorthy, Ashok V; Asghari, Mehdi

2010-09-13

430

Improved Thermal Stability of RF Power BJT with Ballast Circuits  

NASA Astrophysics Data System (ADS)

To improve thermal stability and relieve current convergence in rf power bjts, an embedded active CMOS ballast circuit is proposed. By detecting the inhomogeneous temperature through distributed temperature sensors, the adjacent ballast circuit is triggered to shunt the base convergence current of the power BJT cell, performing the ballast protection for the device. Simulations and measurements validate the effectiveness of the proposed ballast circuit. Compared to conventional ballast resistor methods, the improved device integrated with ballast circuits exhibits superior electrical performance. The single ballast circuit only consumes 6.5 mW with additional occupied area of 2530 um2.

Guo, Benqing; Zhang, Qingzhong

2013-12-01

431

Heat engine development for solar thermal power systems  

NASA Technical Reports Server (NTRS)

The technical status of three heat engines (Stirling, high-temperature Brayton, and Combined cycle) for use in solar thermal power systems is presented. Performance goals necessary to develop a system competitive with conventional power requirements include an external heated engine output less than 40 kW, and efficiency power conversion subsystem at least 40% at rated output, and a half-power efficiency of at least 37%. Results show that the Stirling engine can offer a 39% efficiency with 100 hours of life, and a 20% efficiency with 10,000 hours of life, but problems with seals and heater heads exist. With a demonstrated efficiency near 31% at 1500 F and a minimum lifetime of 100,000 hours, the Brayton engine does not offer sufficient engine lifetime, efficiency, and maintenance for solar thermal power systems. Examination of the Rankine bottoming cycle of the Combined cycle engine reveals a 30 year lifetime, but a low efficiency. Additional development of engines for solar use is primarily in the areas of components to provide a long lifetime, high reliability, and low maintenance (no more than $0.001/kW-hr).

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

1981-01-01

432

Aluminide Coatings for Power-Generation Applications  

SciTech Connect

Aluminide coatings are of interest for many high temperature applications because of the possibility of improving the oxidation of structural alloys by forming a protective external alumina scale. In order to develop a comprehensive lifetime evaluation approach for aluminide coatings used in fossil energy systems, some of the important issues have been addressed in this report for aluminide coatings on Fe-based alloys (Task I) and on Ni-based alloys (Task II). In Task I, the oxidation behavior of iron aluminide coatings synthesized by chemical vapor deposition (CVD) was studied in air + 10vol.% H{sub 2}O in the temperature range of 700-800 C and the interdiffusion behavior between the coating and substrate was investigated in air at 500-800 C. Commercial ferritic (Fe-9Cr-1Mo) and type 304L (Fe-18Cr-9Ni, nominally) austenitic stainless steels were used as the substrates. For the oxidation study, the as-deposited coating consisted of a thin (<5 {micro}m), Al-rich outer layer above a thicker (30-50 {micro}m), lower Al inner layer. The specimens were cycled to 1000 1-h cycles at 700 C and 500 1-h cycles at 800 C, respectively. The CVD coating specimens showed excellent performance in the water vapor environment at both temperatures, while the uncoated alloys were severely attacked. These results suggest that an aluminide coating can substantially improve resistance to water vapor attack under these conditions. For the interdiffusion study, the ferritic and austenitic steels were coated with relatively thicker aluminide coatings consisting of a 20-25 {micro}m outer layer and a 150-250 {micro}m inner layer. The composition profiles before and after interdiffusion testing (up to 5,000h) were measured by electron probe microanalysis (EPMA). The decrease of the Al content at the coating surface was not significant after extended diffusion times ({le} 5,000h) at temperatures {le} 700 C. More interdiffusion occurred at 800 C in coatings on both Fe- 9Cr-1Mo and 304L alloys; a two-phase microstructure was formed in the outer coating layer on 304L after interdiffusion of 2,000h at 800 C. The interdiffusion behavior was simulated using a computer model COSIM (Coating Oxidation and Substrate Interdiffusion Model), which was originally developed for MCrAlY overlay coatings by NASA. Complimentary modeling work using a mathematic model from Heckel et al. also was conducted. Reasonable agreement was observed between the simulated and experimental composition profiles, particularly for aluminide coatings on Fe-9Cr-1Mo ferritic steels. In Task II, the research focused on the CVD aluminide bond coats for thermal barrier coatings (TBC). The martensitic phase transformation in single-phase {beta}-NiAl and (Ni,Pt)Al coatings was studied and compared. After isothermal exposure to 1150 C for 100 hours, the {beta} phase in both types of coatings was transformed to a martensite phase during cooling to room temperature. Martensitic transformation also was observed in the (Ni,Pt)Al bond coat with and without the ceramic top layer after thermal cycling at 1150 C (700 1-h cycles). Such transformation resulted from Al depletion in the coating due to the formation of the Al{sub 2}O{sub 3} scale on coating surface and interdiffusion between the coating and superalloy substrate. The volume changes associated with the martensitic transformation could affect the coating surface stability (''rumpling'') and thus contributing to TBC failure. To elucidate the effect of Hf levels in the superalloy substrate on the oxidation performance, directionally-solidified Rene 142 superalloys containing three different Hf contents with and without aluminide coatings were cyclically oxidized at 1100 and 1150 C in air. Poor scale adhesion was observed for all bare and NiAl-coated Rene 142 superalloys, as compared with single-crystal superalloys such as Rene N5. Spallation occurred at relatively early stages disregarding the Hf contents in the superalloys. Finally, a platinum plating system has been set up at Tennessee Technological University to carefully control the Pt pla

Zhang, Y

2003-11-17

433

User's manual for levelized power generation cost using a microcomputer  

SciTech Connect

Microcomputer programs for the estimation of levelized electrical power generation costs are described. Procedures for light-water reactor plants and coal-fired plants include capital investment cost, operation and maintenance cost, fuel cycle cost, nuclear decommissioning cost, and levelized total generation cost. Programs are written in Pascal and are run on an Apple II Plus microcomputer.

Fuller, L.C.

1984-08-01

434

Advanced feedwater control for next generation nuclear power systems  

Microsoft Academic Search

In current generation Pressurized Water Reactors (PWRs), the control of Steam Generator level experiences challenges over the full range of plant operating conditions. These challenges can be particularly troublesome in the low power range where the feedwater is highly subcooled and minor changes in the feed flow may cause oscillations in the SG level, potentially leading to reactor trip. Substantial

Hengliang Shen

2006-01-01

435

Piezoelectric and Semiconducting Coupled Power Generating Process of a  

E-print Network

Piezoelectric and Semiconducting Coupled Power Generating Process of a Single ZnO Belt observation of piezoelectric generation from a single ZnO wire/belt for illustrating a fundamental process and stored by piezoelectric potential, and later converts into piezoelectric energy. The mechanism

Wang, Zhong L.

436

Flywheel-generator-rectifiers as large magnet pulsed power supplies  

Microsoft Academic Search

A typical generator-rectifier, which would be suitable for a magnet pulsed power supply is described and the fundamental machine equations used to create an original mathematical model. The model is used to examine the operation of the supply under typical load conditions and the discussion of the results is related to the generator design.

J. B. Hicks

1976-01-01

437

A power system stabilizer for DFIG-based wind generation  

Microsoft Academic Search

A power system stabilizer (PSS) for a wind turbine employing a doubly fed induction generator (DFIG) is presented. It is shown that this PSS can significantly influence the contribution that a DFIG-based wind farm can make to network damping. A simple, generic test network that combines synchronous and wind farm generation is used to demonstrate system performance contributions. The results

F. Michael Hughes; Olimpo Anaya-Lara; Nicholas Jenkins; Goran Strbac

2006-01-01

438

Powerformers: A breakthrough of high-voltage power generators  

Microsoft Academic Search

This article deals with the powerformer, a new generator that can be directly connected to the transmission network without the need for a step-up transformer. Due to the powerformer's ability to generate electricity at transmission voltage levels, it offers considerable gains with respect to reactive power production and plant efficiency. Hence, a powerformer both facilitates network stability and decreases the

Ibrahim Metwally; R. M. Radwan; A. M. Abou-Elyazied

2008-01-01

439

Thermoelectric Power Generation Allison Duh and Joel Dungan  

E-print Network

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. Thermoelectric systems capitalize on semiconductor charge carriers excited by a temperature difference to convert

Lavaei, Javad

440

Lamp for generating high power ultraviolet radiation  

DOEpatents

The apparatus is a gas filled ultraviolet generating lamp for use as a liquid purifier. The lamp is powred by high voltage AC, but has no metallic electrodes within or in contact with the gas enclosure which is constructed as two concentric quartz cylinders sealed together at their ends with the gas fill between the cylinders. Cooling liquid is pumped through the volume inside the inner quartz cylinder where an electrically conductive pipe spaced from the inner cylinder is used to supply the cooling liquid and act as the high voltage electrode. The gas enclosure is enclosed within but spaced from a metal housing which is connected to operate as the ground electrode of the circuit and through which the treated fluid flows. Thus, the electrical circuit is from the central pipe, and through the cooling liquid, the gas enclosure, the treated liquid on the outside of the outer quartz cylinder, and to the housing. The high voltage electrode is electrically isolated from the source of cooling liquid by a length of insulated hose which also supplies the cooling liquid.

Morgan, Gary L. (Elkridge, MD); Potter, James M. (Los Alamos, NM)

2001-01-01

441

Thermal energy storage units for solar electric power plants  

Microsoft Academic Search

Several types of heat storage units for solar power plants with thermodynamic cycles of energy conversion are examined, including specific-heat units (particularly water-vapor devices), thermochemical units, and phase-change units. The dependence of specific capital costs for heat storage units upon time of operation is discussed, and particular consideration is give to types of connections of specific-heat units into the thermal

V. I. Gudkov; K. N. Chakalev

1982-01-01

442

Thermal and Power Delivery Challenges in 3D ICs  

Microsoft Academic Search

\\u000a Compared to their 2D counterparts, 3D integrated circuits provide the potential for tremendously increased levels of integration\\u000a per unit footprint. While this property is attractive for many applications, it also creates more stringent design bottlenecks\\u000a in the areas of thermal management and power delivery. First, due to increased integration, the amount of heat per unit footprint\\u000a increases, resulting in the

Pulkit Jain; Pingqiang Zhou; Chris H. Kim; Sachin S. Sapatnekar

443

Truncated thermalization of optical waves through supercontinuum generation in photonic crystal fibers  

E-print Network

Truncated thermalization of optical waves through supercontinuum generation in photonic crystal the process of optical wave thermalization through supercontinuum generation in pho- tonic crystal fibers. We, a phenomenon termed super- continuum (SC) generation [10]. Although the interpreta- tion of the mechanisms

Garnier, Josselin

444

A combined photovoltaic\\/thermal electric central power plant  

Microsoft Academic Search

A preliminary design and performance evaluation of the subject power plant has been completed. DC energy is produced by boiling-water-cooled gallium arsenide solar cells covering a central receiver illuminated by a heliostat field with a concentration ratio of one thousand. The steam is used to power a low pressure turbine-generator, with the exhaust steam directly condensed in a dry air

D. F. Gluck

1979-01-01

445

UF6 breeder reactor power plants for electric power generation  

NASA Technical Reports Server (NTRS)

The reactor concept analyzed is a U-233F6 core surrounded by a molten salt (Li(7)F, BeF2, ThF4) blanket. Nuclear survey calculations were carried out for both spherical and cylindrical geometries. Thermodynamic cycle calculations were performed for a variety of Rankine cycles. A conceptual design is presented along with a system layout for a 1000 MW stationary power plant. Advantages of the gas core breeder reactor (GCBR) are as follows: (1) high efficiency; (2) simplified on-line reprocessing; (3) inherent safety considerations; (4) high breeding ratio; (5) possibility of burning all or most of the long-lived nuclear waste actinides; and (6) possibility of extrapolating the technology to higher temperatures and MHD direct conversion.

Rust, J. H.; Clement, J. D.; Hohl, F.

1976-01-01

446

Railguns powered by explosive driven flux compression generators  

SciTech Connect

Explosive driven flux compression generators (FCG's) are single-shot devices that convert part of the energy of high explosives into electromagnetic energy. Some classes of these generators have served quite well as railgun power sources. In this paper and the following paper we describe strip and helical type FCG's, both of which are in use in the Los Alamos railgun program. Advantages and disadvantages these generators have for railgun power supplies will be discussed, together with experimental results obtained and some of the diagnostics we have found particularly useful.

Fowler, C.M.; Zimmermann, E.L.; Cummings, C.E.; Davidson, R.F.; Foley, E.; Hawke, R.S.; Kerrisk, J.F.; Parker, J.V.; Parsons, W.M.; Peterson, D.R.

1986-01-01

447

Study of thermal interfaces aging for power electronics applications J.-P. Ousten, Z. Khatir  

E-print Network

Study of thermal interfaces aging for power electronics applications J.-P. Ousten, Z. Khatir. Introduction The current trend in power electronics is to design power modules with high power density the thermal interfaces specifically dedicated to power electronics since they represent a very small part

Boyer, Edmond

448

Performance of rf-assisted magnetohydrodynamics power generator  

SciTech Connect

The present paper describes the performance of a radio-frequency (rf) electromagnetic-field-assisted magnetohydrodynamics (MHD) electrical power generator and compares it to a multiple-load MHD generator. rf heating which is superimposed on self-excited Joule heating preionizes cesium-seeded helium gas independent of the in situ loading conditions, whereby Hall potential profile is improved and electron temperature is increased. Furthermore, the dynamic stabilization effect cancels ionization instability and homogenizes plasma structure, which is the most important superiority of the rf-power assistance over a conventional plasma actuation by loading-rate control. The power-generating performance is significantly improved with the aid of the rf power under wide seeding and loading conditions, where the electrical load-matching characteristic is slightly changed.

Murakami, Tomoyuki; Okuno, Yoshihiro; Yamasaki, Hiroyuki [Department of Energy Sciences, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502 (Japan)

2005-11-15

449

Rankine engine solar power generation. I - Performance and economic analysis  

NASA Technical Reports Server (NTRS)

Results of a computer simulation of the performance of a solar flat plate collector powered electrical generation system are presented. The simulation was configured to include locations in New Mexico, North Dakota, Tennessee, and Massachusetts, and considered a water-based heat-transfer fluid collector system with storage. The collectors also powered a Rankine-cycle boiler filled with a low temperature working fluid. The generator was considered to be run only when excess solar heat and full storage would otherwise require heat purging through the collectors. All power was directed into the utility grid. The solar powered generator unit addition was found to be dependent on site location and collector area, and reduced the effective solar cost with collector areas greater than 400-670 sq m. The sites were economically ranked, best to worst: New Mexico, North Dakota, Massachusetts, and Tennessee.

Gossler, A. A.; Orrock, J. E.

1981-01-01

450

MEMS-Based Power Generation Techniques for Implantable Biosensing Applications  

PubMed Central

Implantable biosensing is attractive for both medical monitoring and diagnostic applications. It is possible to monitor phenomena such as physical loads on joints or implants, vital signs, or osseointegration in vivo and in real time. Microelectromechanical (MEMS)-based generation techniques can allow for the autonomous operation of implantable biosensors by generating electrical power to replace or supplement existing battery-based power systems. By supplementing existing battery-based power systems for implantable biosensors, the operational lifetime of the sensor is increased. In addition, the potential for a greater amount of available power allows additional components to be added to the biosensing module, such as computational and wireless and components, improving functionality and performance of the biosensor. Photovoltaic, thermovoltaic, micro fuel cell, electrostatic, electromagnetic, and piezoelectric based generation schemes are evaluated in this paper for applicability for implantable biosensing. MEMS-based generation techniques that harvest ambient energy, such as vibration, are much better suited for implantable biosensing applications than fuel-based approaches, producing up to milliwatts of electrical power. High power density MEMS-based approaches, such as piezoelectric and electromagnetic schemes, allow for supplemental and replacement power schemes for biosensing applications to improve device capabilities and performance. In addition, this may allow for the biosensor to be further miniaturized, reducing the need for relatively large batteries with respect to device size. This would cause the implanted biosensor to be less invasive, increasing the quality of care received by the patient. PMID:22319362

Lueke, Jonathan; Moussa, Walied A.

2011-01-01

451

PLATO Power--a robust, low environmental impact power generation system for the Antarctic plateau  

E-print Network

Observatory) is the third-generation astronomical site-testing laboratory designed by the University of NewPLATO Power--a robust, low environmental impact power generation system for the Antarctic plateau South Wales. This facility is operating autonomously to collect both scientific and site-testing data

Ashley, Michael C. B.

452

Liquid phase sintered composite solders for next generation thermal interface applications  

NASA Astrophysics Data System (ADS)

It is undeniable that electronics are becoming increasingly powerful and that there is continual effort towards miniaturization of these devices and thus increasing heat generation requires a new paradigm in thermal interface materials (TIM) design. This work was aimed at optimizing the processing parameters and characterizing the performance of Cu-In composite solders produced by liquid phase sintering (LPS). These composites comprise a high-melting phase (HMP) such as Cu embedded in a matrix of a low-melting phase (LMP) such as In. Copper contributes to high thermal and electrical conductivity of composites, whereas the soft In matrix helps maintain high shear compliance. This combination of high electrical/thermal conductivities and high shear compliance makes these solders suitable for a range of next-generation thermal interface material (TIM) and interconnect (IC) applications. After considering a range of compositions, a solder with 60 volume percent In was found to possess the requisite combination of high compliance and high conductivity. During the study, interfacial engineering was introduced to slow down the reaction between Cu and In, and hence further improve the performance of composite solders. A dual interfacial layer consisting of Al 2O3 and Au was used to mitigate the reaction between Cu and In. A 1 nm Al2O3 layer was used as a diffusion barrier to prohibit the inter-diffusion between Cu and In, while a 20 nm Au layer was coated on top of the ceramic Al2O3 for wetting enhancement. The dual layer increased the thermal conductivity of the solder by a factor of ˜2 while reducing the yield strength to make the solder more compliant. The effects of particle size, shape and volume fraction was also studied, and a simple model was utilized to explain the trends in the mechanical and the thermal properties. The optimized Cu-In composite solders were further used to study the performance of solder joints. Mechanical properties under shear and joint thermal resistance were measured as a function of joint thickness, thermal excursion history, and different inter-layers between solder and Cu. Minimizing interfacial contact-resistance is desired, especially when the joint thickness becomes sub-millimeter, and hence role of inter-layer on the contact-resistance was studied.

Liu, Jia

453

Stability analysis of free piston Stirling engine power generation system  

NASA Astrophysics Data System (ADS)

This paper presents a stability analysis of the free-piston Stirling engine and linear alternator power generation system. Such a system operates under sustained mechanical oscillators, stability of the system is important for proper operation, and as a criterion in selecting the tuning capacitor. The stability criterion of the system is that the rate of change in power dissipation and electric power output is always faster than the rate of the power generated by the engine. The dynamic equations and model of the system are developed in this paper. Frequency domain analysis and Bode plot techniques are utilized in the study. The stable operating frequency region corresponding to different levels of power output are then determined.

Fu, Z. X.; Nasar, S. A.; Rosswurm, Mark

454

Thermal vacuum life test facility for radioisotope thermoelectric generators  

SciTech Connect

In the late 1970's, the Department of Energy (DOE) assigned Monsanto Research Corporation, Mound Facility, now operated by EG G Mound Applied Technologies, the responsibility for assembling and testing General Purpose Heat Source (GPHS) radioisotope thermoelectric generators (RTGs). Assembled and tested were five RTGs, which included four flight units and one non-flight qualification unit. Figure 1 shows the RTG, which was designed by General Electric AstroSpace Division (GE/ASD) to produce 285 W of electrical power. A detailed description of the processes for RTG assembly and testing is presented by Amos and Goebel (1989). The RTG performance data are described by Bennett, et al. (1986). The flight units will provide electrical power for the National Aeronautics and Space Administration's (NASA) Galileo mission to Jupiter (two RTGs) and the joint NASA/European Space Agency (ESA) Ulysses mission to study the polar regions of the sun (one RTG). The remaining flight unit will serve as the spare for both missions, and a non-flight qualification unit was assembled and tested to ensure that performance criteria were adequately met. 4 refs., 3 figs.

Deaton, R.L.; Goebel, C.J.; Amos, W.R.

1990-01-01

455

Pump starting system for sea thermal power plant  

Microsoft Academic Search

In a turbine driven power generating plant of the type using for example a hydrocarbon or halocarbon as the working fluid operating on or near the surface of an ocean, warm surface water is used as a source of heat for a boiler and cold water pumped from substantial depths is used to condense the working fluid after it has

1977-01-01

456

Solar thermal power system based on optical transmission  

Microsoft Academic Search

In the solar tower concept, a multiplicity of mass produced heliostats reflect sunlight to an elevated central receiver where it is absorbed as heat and transported to the ground. This paper presents the results of an NSF\\/RANN funded study of the technical and economic feasibility of this approach for powering a 10-500 MW electrical generator. A computer model of the

L. L. vant-Hull; A. F. Hildebrandt

1976-01-01

457

Thermal Stress Calculations for Heatpipe-Cooled Reactor Power Systems  

NASA Astrophysics Data System (ADS)

A heatpipe-cooled fast reactor concept has been under development at Los Alamos National Laboratory for the past several years, to be used as a power source for nuclear electric propulsion (NEP) or as a planetary surface power system. The reactor core consists of an array of modules that are held together by a core lateral restraint system. Each module includes a single heatpipe surrounded by 3-6 clad fuel pins. As part of this development effort, a partial array of a candidate heatpipe-cooled reactor is to be tested in the SAFE-100 experimental program at the Marshall Space Flight Center. The partial array comprises 19 3-pin modules, which are powered by resistance heaters. This paper describes the analyses that were performed in support of this test program, to assess thermal and structural performance and to specify the test conditions needed to simulate reactor operating conditions.

Kapernick, Richard J.; Guffee, Ray M.

2003-01-01

458

Low-power high-voltage high-frequency power supply for ozone generation  

Microsoft Academic Search

A low-cost high-frequency power supply for ozone generation is presented in this paper. The paper addresses two important issues. Firstly, the ozone reactor is tested at high frequency and a new model of this type of load is proposed. Secondly, the power supply stage is presented and analyzed, obtaining some important characteristics that allow the correct design of this power

J. Marcos Alonso; J. Cardesin; E. L. Corominas; M. Rico-Secades; J. Garcia

2004-01-01

459

Coal-fired high performance power generating system  

SciTech Connect

The goals of the program are to develop a coal-fired high performance power generation system (HIPPS) by the year 2000 that is capable of > 47% thermal efficiency; NO[sub x] SO [sub x] and Particulates < 25% NSPS; Cost of electricity 10% lower; coal > 65% of heat input and all solid wastes benign. In order to achieve these goals our team has outlined a research plan based on an optimized analysis of a 250 MW[sub e] combined cycle system applicable to both frame type and aeroderivative gas turbines. Under the constraints of the cycle analysis we have designed a high temperature advanced furnace (HITAF) which integrates several combustor and air heater designs with appropriate ash management procedures. Most of this report discusses the details of work on these components, and the R D Plan for future work. The discussion of the combustor designs illustrates how detailed modeling can be an effective tool to estimate NO[sub x] production, minimum burnout lengths, combustion temperatures and even particulate impact on the combustor walls. When our model is applied to the long flame concept it indicates that fuel bound nitrogen will limit the range of coals that can use this approach. For high nitrogen coals a rapid mixing, rich-lean, deep staging combustor will be necessary. The air heater design has evolved into two segments: a convective heat exchanger downstream of the combustion process; a radiant panel heat exchanger, located in the combustor walls; The relative amount of heat transferred either radiatively or convectively will depend on the combustor type and the ash properties.

Not Available

1992-07-01

460

On-line diagnostic system for power generators  

SciTech Connect

A novel approach to diagnostics of a power generator is developed. It utilizes readily available data acquired by the existing computer-based monitoring/control system. Diagnostic procedures detect various trends in the generator data and interpret these trends in the generator data and interpret these trends as changes in the generator performance caused by incipient failures. Results of trend analyses, subjected to statistical validation, facilitate failure prediction and identification thus providing the justification for service when needed. The procedures are incorporated in a diagnostic system implemented in a PC interfaced with the existing VAX-based process monitoring and control system. The diagnostic system provides graphical display of the diagnostic messages.

Skormin, V.A. [Binghamton Univ., NY (United States). Watson School; Goodenough, G.S. [New York State Electric and Gas Corp., Binghamton, NY (United States); Huber, R.K. [Eastman Kodak Co., Rochester, NY (United States)

1996-12-31

461

DOWNHOLE POWER GENERATION AND WIRELESS COMMUNICATIONS FOR INTELLIGENT COMPLETIONS APPLICATIONS  

SciTech Connect

The fourth quarter of the project was dedicated to the manufacturing of the mechanical system for wireless communications and the power generation module and inspection pre assembly of the mechanical components. Another emphasis for the quarter was the development of filter control and signal detection software. The tasks accomplished during this report period were: (1) Dimensional issues were resolved and revised drawings for manufacturing of the wireless communications gauge and power generator were completed and sent to a machine shop for manufacturing. (2) Finalized the requirements and fittings and connections for testing the tool in the Halliburton flow loop. (3) The new acoustic generator was manufactured successfully and it was delivered during this quarter. The assembly will be outsourced for plastic coating in preparation for hostile environment use. (4) The acoustic two-way communications development continued to progress. The real time firmware for the surface system was developed and the processor was able to detect and process the data frame transmitted from downhole. The analog section of the tool was also developed and it is being tested for filtering capabilities and signal detection and amplification. (5) The new transformer to drive the acoustic generator assembly was manufactured and was successfully tested. Spring mandrel design showed increased acoustic output on the pipe and was implemented. (6) PCBA board carrier with board set was tested for function and fit and is 100% complete. (7) Filter control software is complete and software to allow modification of communication parameters dynamically is 50% complete. (8) All mechanical parts to assemble the wireless gauge and power generator have been received and verified to be within specification. (9) Acoustic generator has been assembled in the tool mandrel and tested successfully. (10) The circuit required to harvest the power generated downhole has been designed and the power generator components have been received.

Paul Tubel

2003-10-14

462

Sea thermal power; A survey study for the Arab coastal waters  

SciTech Connect

One of the promising types of renewable energy resource that has potential applications in the Arab world is proposed and described in this article. Known as ocean thermal energy conversion (OTEC), its feasibility is investigated for the Red Sea and the Arabian Gulf/Gulf of Oman. Data on thermal gradients are surveyed, collected, and reported. Promising parameters have been identified for some specific locations along these coastal waters. The proposed system can serve the dual purpose of providing electric power and desalinated water, which is needed by the Arab world. Construction strategies for the OTEC systems are introduced. Building plant-ship for utilizing the generated power in the production of hydrogen is recommended. Thus energy could be transported as LH{sub 2} (liquid hydrogen), MeOH (methanol), or NH{sub 3} (ammonia) for end-use consumption or export.

Abdell-AAL, H.K.; Khan, M.M. (Dept. of Chemical Engineering, King Fahd Univ. of Petroleum and Minerals, Dhahran 31261 (SA))

1990-01-01

463

Impact of a 1,000-foot thermal mixing zone on the steam electric power industry  

SciTech Connect

Thermal discharge requirements for power plants using once-through cooling systems are based on state water quality standards for temperatures that must be met outside of designated mixing zones. This study evaluates the impact of limiting the extent of thermal mixing zones. This study evaluates the impact of limiting the extent of thermal mixing zones to no more than 1,000 feet from the discharge point. Data were collected from 79 steam electric plants. Of the plants currently using once-through cooling systems, 74% could not meet current thermal standards at the edge of a 1,000-foot mixing zone. Of this total, 68% would retrofit cooling towers, and 6% would retrofit diffusers. The estimated nationwide capital cost for retrofitting plants that could not meet current thermal standards at the edge of a 1,000-foot mixing zone is $21.4 billion. Conversion of a plant from once-through cooling to cooling towers or addition of diffusers would result in a lower energy output from that plant. For the affected plants, the total estimated replacement cost would be $370 to $590 million per year. Some power companies would have to construct new generating capacity to meet the increased energy demand. The estimated nationwide cost of this additional capacity would be $1.2 to $4.8 billion. In addition to the direct costs associated with compliance with a 1,000-foot mixing zone limit, other secondary environmental impacts would also occur. Generation of the additional power needed would increase carbon dioxide emissions by an estimated 8.3 million tons per year. In addition, conversion from once-through cooling systems to cooling towers at affected plants would result in increased evaporation of about 2.7 million gallons of water per minute nationwide.

Veil, J.A.

1994-04-01

464

Large-scale terrestrial solar cell power generation cost: A preliminary assessment  

NASA Technical Reports Server (NTRS)

A cost study was made to assess the potential of the large-scale use of solar cell power for terrestrial applications. The incentive is the attraction of a zero-pollution source of power for wide-scale use. Unlike many other concepts for low-pollution power generation, even thermal pollution is avoided since only the incident solar flux is utilized. To provide a basis for comparison and a perspective for evaluation, the pertinent technology was treated in two categories: current and optimistic. Factors considered were solar cells, array assembly, power conditioning, site preparation, buildings, maintenance, and operation. The capital investment was assumed to be amortized over 30 years. The useful life of the solar cell array was assumed to be 10 years, and the cases of zero and 50-percent performance deg-radation were considered. Land costs, taxes, and profits were not included in this study because it was found too difficult to provide good generalized estimates of these items. On the basis of the factors considered, it is shown that even for optimistic projections of technology, electric power from large-sclae terrestrial use of solar cells is approximately two to three orders of magnitude more costly than current electric power generation from either fossil or nuclear fuel powerplants. For solar cell power generation to be a viable competitor on a cost basis, technological breakthroughs would be required in both solar cell and array fabrication and in site preparation.

Spakowski, A. E.; Shure, L. I.

1972-01-01

465

Analysis of series compensated self excited induction generators for autonomous power generation  

Microsoft Academic Search

The paper presents an analytical technique to predict the steady state performance of a 3-phase self excited induction generator for autonomous power generation which employs both shunt and series capacitors for voltage regulation. The system is modeled using an equivalent circuit which interconnects the machine, capacitor and the load. Simplifying appropriate loop equations of the circuit leads to two nonlinear

S. S. Murthy; C. Prabhu; A. K. Tandon; M. O. Vaishya

1996-01-01

466

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

NASA Technical Reports Server (NTRS)

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

1991-01-01

467

Re-circulating power, unit costs and thermal pollution of fusion power stations  

Microsoft Academic Search

The fraction ? of electrical power re-circulated is shown to be of crucial importance in assessing the credibility of fusion systems as commercial reactors, and it is advocated that ? should replace the more commonly used criterion Q, the energy amplification in the fusion reactor itself. Both unit costs and thermal pollution are shown to scale as (constant + ?)\\/(1-?)

P. A. Davenport

1978-01-01

468

A New Strategy for Tie-Line Power Regulation of HydroThermal Interconnected Power System Based on Benefit Analysis  

Microsoft Academic Search

Considering different character between hydroelectric power and thermal power contributed to tie-line, as well as the cost function of the whole interconnected system under electric power market environments, this paper presents a new optimization strategy based on benefit analysis to solve the power regulation on tie-line in hydro-thermal interconnected power system. The units relating to tie-line can be procured by

Wu Jiekang; Han Junfeng; Jiang Cheng; Lu Wenling

2009-01-01

469

Medical aspects of power generation, present and future.  

PubMed

It can be seen that the radiation emissions of nuclear power plants are small indeed, compared to natural background radiation and other man-made sources of radiation. For example, the poulation is exposed to 100 times more radiation from television sets than from nuclear power reactors. The assumed risks to the people in this country from nuclear power reactors are also small compared to the normal risks which are tolerated in this society. The complete elimination of all hazards is a most difficult if not impossible task. If we need and desire a certain level of electrical energy, if we must choose between alternative sourves of the energy, then it is apparent that the total impact on our health from nuclear power generation of electricity, under normal operations and in consideration of catastrophic accident probabilities, is significantly less than that of continuing or increasing use of fossil fuels to generate electricity. PMID:522630

Linnemann, R E

1979-01-01

470

Experiments on H2-O2MHD power generation  

NASA Technical Reports Server (NTRS)

Magnetohydrodynamic power generation experiments utilizing a cesium-seeded H2-O2 working fluid were carried out using a diverging area Hall duct having an entrance Mach number of 2. The experiments were conducted in a high-field strength cryomagnet facility at field strengths up to 5 tesla. The effects of power takeoff location, axial duct location within the magnetic field, generator loading, B-field strength, and electrode breakdown voltage were investigated. For the operating conditions of these experiments, it is found that the power output increases with the square of the B-field and can be limited by choking of the channel or interelectrode voltage breakdown which occurs at Hall fields greater than 50 volts/insulator. Peak power densities of greater than 100 MW/cu M were achieved.

Smith, J. M.

1980-01-01

471

Development of Next Generation Segmented Thermoelectric Radioisotope Power Systems  

NASA Astrophysics Data System (ADS)

Radioisotope thermoelectric generators have been used for space-based applications since 1961 with a total of 22 space missions that have successfully used RTGs for electrical power production. The key advantages of radioisotope thermoelectric generators (RTGs) are their long life, robustness, compact size, and high reliability. Thermoelectric converters are easily scalable, and possess a linear current-voltage curve, making power generation easy to control via a shunt regulator and shunt radiator. They produce no noise, vibration or torque during operation. These properties have made RTGs ideally suitable for auto