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Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
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1

Heat Recovery Steam Generator Cycle Chemistry Instrumentation  

Science Conference Proceedings (OSTI)

Effective monitoring of the purity of water and steam is an integral part of any productive cycle chemistry monitoring program. The Electric Power Research Institute's (EPRI's) heat recovery steam generator (HRSG) cycle chemistry guidelines identified a group of core monitoring parameters that are considered the minimum requirements. Meeting these requirements is part of EPRI's cycle chemistry benchmarking criteria for HRSGs. In addition to the core parameters, many chemistry parameters might need to be ...

2010-11-19T23:59:59.000Z

2

Economizer refrigeration cycle space heating and cooling system and process  

DOE Patents (OSTI)

This invention relates to heating and cooling systems and more particularly to an improved system utilizing a Stirling Cycle engine heat pump in a refrigeration cycle. 18 figs.

Jardine, D.M.

1983-03-22T23:59:59.000Z

3

Economizer refrigeration cycle space heating and cooling system and process  

DOE Patents (OSTI)

This invention relates to heating and cooling systems and more particularly to an improved system utilizing a Stirling Cycle engine heat pump in a refrigeration cycle.

Jardine, Douglas M. (Colorado Springs, CO)

1983-01-01T23:59:59.000Z

4

Geothermal heat cycle research: Supercritical cycle with horizontal counterflow condenser  

DOE Green Energy (OSTI)

The Heat Cycle Research Program, which is being conducted for the Department of Energy, has as its objective the development of the technology for effecting the improved utilization of moderate temperature geothermal resources. To meet this objective, the program has as one of its goals to improve the performance of geothermal binary cycles to levels approaching the practicable thermodynamic maximum. In pursuit of this goal, tests are being conducted at the Heat Cycle Research Facility located at the DOE Geothermal Test Facility, East Mesa, California. The current testing involves the investigation of binary power cycle performance utilizing mixtures of non-adjacent hydrocarbons as the working fluids, with supercritical vaporization and in-tube condensation of the working fluid. In addition to the present test program, preparations are being made to investigate the binary cycle performance improvements which can be achieved by allowing supersaturated vapor expansions in the turbine. These efforts are anticipated to verify that through the utilization of these advanced power cycle concepts and allowing the supersaturated turbine expansions, improvements of up to 28% in the net geofluid effectiveness (net watt hours plant output per pound of geofluid) over conventional binary power plants can be achieved. Results are presented for the recent testing including those tests examining the performance of the countercurrent condenser at different tube inclinations. Performance of the heaters and the condenser in a vertical orientation can be predicted well with existing methods and data. The condenser in its near horizontal orientation performs slightly worse than in its vertical orientation. Some problems have been encountered in predicting the performance in the horizontal orientation. There is no evidence of departure from integral condensation in either orientation.

Mines, G.L.; Swank, W.D.; Bliem, C.J.

1987-01-01T23:59:59.000Z

5

Sulfuric acid-sulfur heat storage cycle  

DOE Patents (OSTI)

A method of storing heat is provided utilizing a chemical cycle which interconverts sulfuric acid and sulfur. The method can be used to levelize the energy obtained from intermittent heat sources, such as solar collectors. Dilute sulfuric acid is concentrated by evaporation of water, and the concentrated sulfuric acid is boiled and decomposed using intense heat from the heat source, forming sulfur dioxide and oxygen. The sulfur dioxide is reacted with water in a disproportionation reaction yielding dilute sulfuric acid, which is recycled, and elemental sulfur. The sulfur has substantial potential chemical energy and represents the storage of a significant portion of the energy obtained from the heat source. The sulfur is burned whenever required to release the stored energy. A particularly advantageous use of the heat storage method is in conjunction with a solar-powered facility which uses the Bunsen reaction in a water-splitting process. The energy storage method is used to levelize the availability of solar energy while some of the sulfur dioxide produced in the heat storage reactions is converted to sulfuric acid in the Bunsen reaction.

Norman, John H. (LaJolla, CA)

1983-12-20T23:59:59.000Z

6

Heat Pump Cycle with Solution Circuit and Internal Heat Exchange  

E-Print Network (OSTI)

Vapor compression heat pumps which employ working fluid mixtures rather than pure substances offer significant advantages leading to larger temperature lifts at low pressure ratios or to completely new applications. The main feature of such cycles is the fact that the working fluid mixture does not evaporate completely in the evaporator. The remaining liquid phase is then recirculated by means of a liquid pump into the condenser. This yields significant improvements compared to conventional systems: -Adjustable gliding temperature intervals in desorber and absorber by merely adjusting the flow rate through the liquid pump and/or –Dramatically reducing pressure ratios (to typically 45% of the one for a single working fluid heat pump) for a given temperature lift due to staging of the solution circuit. The latter is accomplished when a two-stage version of this cycle is used. In this paper, another version of such cycles will be discussed which offers the same low pressure ratio as a previously discussed two-stage cycle, but requires only one liquid pump. The performance of this cycle has been calculated and the results are presented.

Radermacher, R.

1986-06-01T23:59:59.000Z

7

Performance limits of power cycles using low temperature heat sources  

Science Conference Proceedings (OSTI)

A systematic analysis of a Rankine cycle using R134a as the working fluid and a finite (314.5 kg/s) low temperature (100 °C) heat source shows that, for any fixed net power output, the evaporation pressure has upper and lower limits which depend ... Keywords: energy analysis, exergy analysis, finite size thermodynamics, optimisation

Mohammed Khennich; Nicolas Galanis

2010-02-01T23:59:59.000Z

8

Heating fuel choice shows electricity and natural gas roughly ...  

U.S. Energy Information Administration (EIA)

Petroleum & Other Liquids. Crude oil, gasoline, heating oil, diesel, propane, and other liquids including biofuels and natural gas liquids. Natural Gas

9

Heat Cycle Research Experimental Program, FY-1985  

DOE Green Energy (OSTI)

The Heat Cycle Research Program, which is being conducted for the Department of Energy, has as its objective the development of the technology for effecting improved utilization of moderate temperature geothermal resources. Testing at the Heat cycle Research Facility located at the DOE Geothermal Test Facility, East Mesa, California is presently being conducted to meet this objective. Current testing involves a supercritical vaporization and counterflow in-tube condensing system. The paper presents a brief description of the test facility and a discussion of the test program. Results of the experiments for the supercritical heaters and the countercurrent, vertical, in-tube condenser are given for both pure and mixed-hydrocarbon working fluids. The heater and condenser behavior predicted by the Heat Transfer Research Institute computer codes used for correlation of the data was in excellent agreement with experimental results. Preliminary results of tests in which the turbine expansion ''passed through the two-phase region'' did not indicate efficiency degradation assignable to these metastable expansion processes. 6 refs., 9 figs.

Bliem, C.J.; Demuth, O.J.; Mines, G.L.; Whitbeck, J.F.

1985-01-01T23:59:59.000Z

10

Interfacing primary heat sources and cycles for thermochemical hydrogen production  

DOE Green Energy (OSTI)

Advantages cited for hydrogen production from water by coupling thermochemical cycles with primary heat include the possibility of high efficiencies. These can be realized only if the cycle approximates the criteria required to match the characteristics of the heat source. Different types of cycles may be necessary for fission reactors, for fusion reactors or for solar furnaces. Very high temperature processes based on decomposition of gaseous H/sub 2/O or CO/sub 2/ appear impractical even for projected solar technology. Cycles based on CdO decomposition are potentially quite efficient and require isothermal heat at temperatures that may be available from solar furnaces of fusion reactors. Sulfuric acid and solid sulfate cycles are potentially useful at temperatures available from each heat source. Solid sulfate cycles offer advantages for isothermal heat sources. All cycles under development include concentration and drying steps. Novel methods for improving such operations would be beneficial.

Bowman, M.G.

1980-01-01T23:59:59.000Z

11

Working on new gas turbine cycle for heat pump drive  

E-Print Network (OSTI)

Working on new gas turbine cycle for heat pump drive FILE COPY TAP By Irwin Stambler, Field Editor DO NOT 16 0 REMOVE 16 Small recuperated gas turbine engine, design rated at 13 hp and 27% efficiency of the cycle- as a heat pump drive for commercial installations. Company is testing prototype gas turbine

Oak Ridge National Laboratory

12

Study of Supercritical Carbon Dioxide Power Cycle for Low Grade Heat Conversion  

Science Conference Proceedings (OSTI)

Research on supercritical carbon dioxide power cycles has been mainly focused on high temperature applications, such as Brayton cycle in a nuclear power plant. This paper conducts a comprehensive study on the feasibility of a CO2-based supercritical power cycle for low-grade heat conversion. Energy and exergy analyses of the cycle were conducted to discuss the obstacles as well as the potentials of using supercritical carbon dioxide as the working fluid for supercritical Rankine cycle, Carbon dioxide has desirable qualities such as low critical temperature, stability, little environmental impact and low cost. However, the low critical temperature might be a disadvantage for the condensation process. Comparison between a carbon dioxide-based supercritical Rankine cycle and an organic fluid-based supercritical Rankine cycle showed that the former needs higher pressure to achieve the same efficiency and a heat recovery system is necessary to desuperheat the turbine exhaust and pre-heat the pressure charged liquid.

Vidhi, Rachana [University of South Florida, Tampa; Goswami, Yogi D. [University of South Florida, Tampa; Chen, Huijuan [University of South Florida, Tampa; Stefanakos, Elias [University of South Florida, Tampa; Kuravi, Sarada [University of South Florida, Tampa; Sabau, Adrian S [ORNL

2011-01-01T23:59:59.000Z

13

Cycle Chemistry Guidelines for Combined Cycle/Heat Recovery Steam Generators (HRSGs)  

Science Conference Proceedings (OSTI)

The cycle chemistry in combined cycle plants influences about 70 of the heat recovery steam generator (HRSG) tube failure mechanisms. These guidelines have been assembled to assist operators and chemists in developing an effective overall cycle chemistry program which will prevent HRSG tube failures (HTF).

2006-03-09T23:59:59.000Z

14

The Seasonal Cycle of Atmospheric Heating and Temperature  

Science Conference Proceedings (OSTI)

The seasonal cycle of the heating of the atmosphere is divided into a component due to direct solar absorption in the atmosphere and a component due to the flux of energy from the surface to the atmosphere via latent, sensible, and radiative heat ...

Aaron Donohoe; David S. Battisti

2013-07-01T23:59:59.000Z

15

Cascaded organic rankine cycles for waste heat utilization  

Science Conference Proceedings (OSTI)

A pair of organic Rankine cycle systems (20, 25) are combined and their respective organic working fluids are chosen such that the organic working fluid of the first organic Rankine cycle is condensed at a condensation temperature that is well above the boiling point of the organic working fluid of the second organic Rankine style system, and a single common heat exchanger (23) is used for both the condenser of the first organic Rankine cycle system and the evaporator of the second organic Rankine cycle system. A preferred organic working fluid of the first system is toluene and that of the second organic working fluid is R245fa.

Radcliff, Thomas D. (Vernon, CT); Biederman, Bruce P. (West Hartford, CT); Brasz, Joost J. (Fayetteville, NY)

2011-05-17T23:59:59.000Z

16

Test Plan for Heat Cycle Research Program, Phase I Supercritical Cycle Tests  

DOE Green Energy (OSTI)

The 60 kW Heat Cycle Research Facility (HCRF) provides a means of examining different concepts and components associated with the generation of electrical power from a geothermal resource using a binary power cycle. In this power cycle the heat or energy in a hot geothermal fluid is transferred to a secondary working fluid. This working fluid is vaporized in the heat exchange process and the vapor is in turn expanded through a turbine which drives a generator producing electrical power. the heat or energy in the vapor leaving the turbine is transferred to a circulating cooling water in the condenser where the working fluid is condensed to a liquid which can be pumped back to the heaters, completing the cycle. This waste heat load in the condenser is in turn transferred from the cooling water to the atmosphere in a cooling tower. The HCRF allows the different components described in the cycle above to be tested as well as the basic cycle itself. This cycle may vary in that the heaters, condenser, cooling system, pumps, etc. may differ in number and type, however the basic cycle does not change significantly. During this sequence of tests, the HCRF is operated using a supercritical vapor generator and a vertical condenser where the condensation occurs inside of the tubes as opposed to the shell side more commonly used in these applications. In addition to providing the data to be used to evaluate the design of these heat exchangers, these supercritical tests provide cycle and component performance data with both single component working fluids and working fluids comprised of different mixtures of hydrocarbons. The use of these mixtures promises to improve cycle performance, in terms of watt-hours per pound of geothermal fluid, provided the countercurrent flow paths can be maintained between the fluids in both the condenser and the heaters. The supercritical heaters and the condenser to be used in this series of tests were designed to provide the desired countercurrent flow paths.

Mines, Greg L.

1983-06-01T23:59:59.000Z

17

Heat exchangers for high-temperature thermodynamic cycles  

SciTech Connect

The special requirements of heat exchangers for high temperature thermodynamic cycles are outlined and discussed with particular emphasis on cost and thermal stress problems. Typical approaches that have been taken to a comprehensive solution intended to meet all of the many boundary conditions are then considered by examining seven typical designs including liquid-to-liquid heat exchangers for nuclear plants, a heater for a closed cycle gas turbine coupled to a fluidized bed coal combustion chamber, steam generators for nuclear plants, a fossil fuel-fired potassium boiler, and a potassium condenser-steam generator. (auth)

Fraas, A.P.

1975-01-01T23:59:59.000Z

18

Turbine Cycle Heat Rate Monitoring: Technology and Application  

Science Conference Proceedings (OSTI)

Research has been completed on available technology for monitoring turbine cycle heat rate and factors affecting the successful deployment of this technology in fossil generating plants. Information has been gathered from interviews with experienced industry plant staff and vendors. Trends were noted and are described in this report. The report is recommended as guidance for power generation fleets and individual plants seeking to establish a successful program for heat rate reduction.

2006-12-20T23:59:59.000Z

19

Eggs Show Arctic Mercury Cycling May Be Linked to Ice Cover  

Science Conference Proceedings (OSTI)

... cycling of mercury in the Arctic biosphere. Credit: D. Roseneau, US Fish and Wildlife Service View hi-resolution image. ...

2011-01-20T23:59:59.000Z

20

Open-Cycle Vapor Compression Heat Pump System  

E-Print Network (OSTI)

In many industrial processes, large quantities of energy are often wasted in the form of low pressure steam and low-grade heat. Economical recovery of these waste energy sources is often difficult due to such factors as low temperature levels and contamination of the steam. In industrial processes that utilize steam directly or as a mode of energy transport, waste energy can be efficiently recovered and upgraded in the form of high-pressure steam by means of an open-cycle steam heat pump system. Recovery and upgrading of these waste steam or heat sources offer a great potential for energy conservation. Thermo Electron has developed, under sponsorship by the Gas Research Institute, Southern California Gas Company, and the Consolidated Natural Gas Service Company, an open-cycle steam heat pump to recover this waste energy in the form of high-pressure process steam. The system utilizes excess low-pressure steam (or that produced from an excess heat source with a waste heat boiler) and compresses this steam to the desired pressure level for process use. The compressor is driven by a gas turbine or gas engine prime mover. To enhance the system performance, the prime mover exhaust and/or cooling jacket heat is recovered to generate additional process steam or hot water. Utilizing the Thermo Electron system, fuel consumption can be 30 percent lower in comparison to a direct-fired boiler. Simple payback periods of 1 to 3 years are generally found for most applications.

Pasquinelli, D. M.; Becker, F. E.

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Overview of recent supercritical binary geothermal cycle experiments from the Heat Cycle Research Program  

DOE Green Energy (OSTI)

The Heat Cycle Research Program, which is being conducted for the Department of Energy, has as its objective the development of the technology for effecting improved utilization of moderate temperature geothermal resources. Testing at the Heat Cycle Research Facility located at the DOE Geothermal Test Facility East Mesa, California involves supercritical vaporization and counterflow in-tube condensing in an organic Rankine cycle. Results of the experiments are given for both pure and mixed-hydrocarbon working fluids. The heater and condenser behavior predicted by the Heat Transfer Research, Inc. computer codes used for correlation of the data was in excellent agreement with experimental results. A special series of tests, conducted with propane and up to approximately 40% isopentane concentration, indicated that a close approach to ''integral'' condensation was occurring in the vertically-oriented condenser. Preliminary results of tests in which the turbine expansion ''passed through the two-phase region'' did not indicate efficiency degradation assignable to these metastable expansion processes.

Demuth, O.J.; Bliem, C.J.; Mines, G.L.; Swank, W.D.

1986-01-01T23:59:59.000Z

22

Comprehensive Cycle Chemistry Guidelines for Combined Cycle/Heat Recovery Steam Generators (HRSGs)  

Science Conference Proceedings (OSTI)

The purity of water and steam is central to ensuring combined cycle/heat recovery steam generator (HRSG) plant component availability and reliability. These guidelines for combined cycle/HRSG plants provide information on the application of all-volatile treatment (AVT), oxygenated treatment (OT), phosphate treatment (PT), caustic treatment (CT), and amine treatment. The guidelines will help operators reduce corrosion and deposition and thereby achieve significant operation and maintenance cost ...

2013-11-08T23:59:59.000Z

23

Stirling cycle heat pump for heating and/or cooling systems  

Science Conference Proceedings (OSTI)

This patent describes a duplex Stirling cycle machine acting as a heat pump. It comprises: a Stirling engine having pistons axially displaceable within parallel cylinders, the engine further having a swashplate rotatable about an axis of, rotation parallel to the cylinders and defining a plane inclined from the axis of rotation. The pistons connected to the swashplate via crossheads whereby axial displacement of the pistons is converted to rotation of the swashplate, and a Stirling cycle heat pump having a compression heat exchanger, an expansion heat exchanger and a regenerator with pistons equal in number to the engine pistons and axially displaceable within cylinders which are oriented co-axially with the engine cylinders. The crossheads further connected to the heat pump pistons whereby the heat pump pistons move simultaneously with the engine pistons over an equal stroke distance.

Meijer, R.J.; Khalili, K.; Meijer, E.; Godett, T.M.

1991-03-05T23:59:59.000Z

24

Thermodynamic modeling of performance of a Miller cycle with engine speed and variable specific heat ratio of working fluid  

Science Conference Proceedings (OSTI)

The performance of an air standard Miller cycle is analyzed using finite-time thermodynamics. The results show that if the compression ratio is less than certain value, the increase of the value of the specific heat ratio will make the power output bigger. ... Keywords: Finite-time processes, Friction, Heat resistance, Internal irreversibility, Miller heat-engine

Rahim Ebrahimi

2011-09-01T23:59:59.000Z

25

A combined power and ejector refrigeration cycle for low temperature heat sources  

Science Conference Proceedings (OSTI)

A combined power and ejector refrigeration cycle for low temperature heat sources is under investigation in this paper. The proposed cycle combines the organic Rankine cycle and the ejector refrigeration cycle. The ejector is driven by the exhausts from the turbine to produce power and refrigeration simultaneously. A simulation was carried out to analyze the cycle performance using R245fa as the working fluid. A thermal efficiency of 34.1%, an effective efficiency of 18.7% and an exergy efficiency of 56.8% can be obtained at a generating temperature of 395 K, a condensing temperature of 298 K and an evaporating temperature of 280 K. Simulation results show that the proposed cycle has a big potential to produce refrigeration and most exergy losses take place in the ejector. (author)

Zheng, B.; Weng, Y.W. [School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200240 (China)

2010-05-15T23:59:59.000Z

26

Deaerator heat exchanger for combined cycle power plant  

SciTech Connect

This patent describes a combined cycle power plant. It comprises a steam turbine including an inlet portion for receiving motive steam and an exhaust portion for exhausting the motive steam that is spent by the steam turbine; a condenser connected to the exhaust portion of the steam turbine for receiving the spent motive steam and for condensing the spent motive steam to a supply of condensate; a gas turbine including an exhaust portion for exhausting waste heat that is produced by the gas turbine in the form of exhaust gases; a heat recovery steam generator connected between the exhaust portion of the gas turbine and the steam turbine, for receiving the waste heat exhausted by the gas turbine, for generating the motive steam from a supply of feedwater heated by the waste heat, and for supplying the motive steam to the steam turbine; a deaerator connected to the condenser for receiving the supply of condensate and for deaerating the condensate to provide the supply of feedwater to the heat recovery steam generator; and a heat exchanger.

Pavel, J.; Richardson, B.L.

1990-10-09T23:59:59.000Z

27

Advanced Multi-Effect Distillation System for Desalination Using Waste Heat fromGas Brayton Cycles  

SciTech Connect

Generation IV high temperature reactor systems use closed gas Brayton Cycles to realize high thermal efficiency in the range of 40% to 60%. The waste heat is removed through coolers by water at substantially greater average temperature than in conventional Rankine steam cycles. This paper introduces an innovative Advanced Multi-Effect Distillation (AMED) design that can enable the production of substantial quantities of low-cost desalinated water using waste heat from closed gas Brayton cycles. A reference AMED design configuration, optimization models, and simplified economics analysis are presented. By using an AMED distillation system the waste heat from closed gas Brayton cycles can be fully utilized to desalinate brackish water and seawater without affecting the cycle thermal efficiency. Analysis shows that cogeneration of electricity and desalinated water can increase net revenues for several Brayton cycles while generating large quantities of potable water. The AMED combining with closed gas Brayton cycles could significantly improve the sustainability and economics of Generation IV high temperature reactors.

Haihua Zhao; Per F. Peterson

2012-10-01T23:59:59.000Z

28

Waste Heat Recovery by Organic Fluid Rankine Cycle  

E-Print Network (OSTI)

The use of Organic Rankine Cycle for waste heat recovery presents several characteristics which are analyzed in details. After a short comparison with steam cycles, the Organic Rankine Cycle is described : its simplicity is shown and achievable efficiencies versus heat source temperature are given. Available fluids are presented. The choice of the fluid allows a good adaptation to temperature and power for each application. The most interesting field for Organic Rankine Cycles are low mechanical powers of a few megawatts and medium temperatures, about 500 C/600 C, for flue gas. The very simple technology of turbines is shown. Three examples are presented. The first one is a test loop of 300 thermal kW built in BERTIN & Cie laboratory to experiment a supersonic turbine designed by the same company for organic vapor at 250 C. The second gives the main characteristics of recovery from exhaust gas of Diesel engines. The last deals with possible recovery from air quenching of clinker in cement plants.

Verneau, A.

1979-01-01T23:59:59.000Z

29

Design of organic Rankine cycles for conversion of waste heat in a polygeneration plant  

E-Print Network (OSTI)

Organic Rankine cycles provide an alternative to traditional steam Rankine cycles for the conversion of low grade heat sources, where steam cycles are known to be less efficient and more expensive. This work examines organic ...

DiGenova, Kevin (Kevin J.)

2011-01-01T23:59:59.000Z

30

Investigation of heat exchanger flow arrangement on performance and cost in a geothermal binary cycle  

DOE Green Energy (OSTI)

The performance of an idealized geothermal binary-fluid-cycle energy conversion system is shown to be a function of the temperatures of brine and working fluid leaving the heat exchanger. System power output, heat exchanger area required and initial well and heat exchanger costs are determined for counterflow, single and multi-pass parallel-counterflow exchangers. Results are presented graphically as functions of the brine and working fluid exit temperatures from the exchanger. Use of the system analysis developed is illustrated by showing quantitatively the advantage of the counterflow over the other flow arrangements considered.

Giedt, W.H.

1976-06-15T23:59:59.000Z

31

Life cycle assessment of base-load heat sources for district heating system options  

Science Conference Proceedings (OSTI)

Purpose There has been an increased interest in utilizing renewable energy sources in district heating systems. District heating systems are centralized systems that provide heat for residential and commercial buildings in a community. While various renewable and conventional energy sources can be used in such systems, many stakeholders are interested in choosing the feasible option with the least environmental impacts. This paper evaluates and compares environmental burdens of alternative energy source options for the base load of a district heating center in Vancouver, British Columbia (BC) using the life cycle assessment method. The considered energy sources include natural gas, wood pellet, sewer heat, and ground heat. Methods The life cycle stages considered in the LCA model cover all stages from fuel production, fuel transmission/transportation, construction, operation, and finally demolition of the district heating system. The impact categories were analyzed based on the IMPACT 2002+ method. Results and discussion On a life-cycle basis, the global warming effect of renewable energy options were at least 200 kgeqCO2 less than that of the natural gas option per MWh of heat produced by the base load system. It was concluded that less than 25% of the upstream global warming impact associated with the wood pellet energy source option was due to transportation activities and about 50% of that was resulted from wood pellet production processes. In comparison with other energy options, the wood pellets option has higher impacts on respiratory of inorganics, terrestrial ecotoxicity, acidification, and nutrification categories. Among renewable options, the global warming impact of heat pump options in the studied case in Vancouver, BC, were lower than the wood pellet option due to BC's low carbon electricity generation profile. Ozone layer depletion and mineral extraction were the highest for the heat pump options due to extensive construction required for these options. Conclusions Natural gas utilization as the primary heat source for district heat production implies environmental complications beyond just the global warming impacts. Diffusing renewable energy sources for generating the base load district heat would reduce human toxicity, ecosystem quality degradation, global warming, and resource depletion compared to the case of natural gas. Reducing fossil fuel dependency in various stages of wood pellet production can remarkably reduce the upstream global warming impact of using wood pellets for district heat generation.

Ghafghazi, Saeed [University of British Columbia, Vancouver; Sowlati, T. [University of British Columbia, Vancouver; Sokhansanj, Shahabaddine [ORNL; Melin, Staffan [Delta Research Corporation

2011-03-01T23:59:59.000Z

32

Analysis of Organic Rankine Cycle for Low and Medium Grade Heat Source  

Science Conference Proceedings (OSTI)

Organic Rankine cycle (ORC) is an effective technique to generate power from low and medium temperature heat source, including industrial waste heat, solar heat, geothermal and biomass etc. Advantages of ORC are high efficiency, simple system, environment ... Keywords: organic Rankine cycle, new energy, waste heat recovery

Zhonghe Han, Yida Yu

2012-07-01T23:59:59.000Z

33

Research of Refrigerant Phase-Change Stirling-Cycle Heat Engines  

Science Conference Proceedings (OSTI)

This paper firstly introduces the principles of Refrigerant Phase-Change Stirling-Cycle solar power towers This heat engines use solar reservoire. When the refrigerant in an engine cylinder absorbs heat from high-temperature heat sources, refrigerant ... Keywords: refrigerant phase-change cycle, heat engines, finite-time thermodynamics

Dezhong Huang; Fuer Wu

2011-01-01T23:59:59.000Z

34

Heat transfer research and power cycle transient modeling  

DOE Green Energy (OSTI)

Fine axial flutes enhance heat transfer in vertical shell-and-tube exchangers with water inside the tubes and ammonia evaporating or condensing in layer flow on the shell side. Single-tube experiments with R-11 and ammonia indicate local shell-side coefficients 3 to 5 times those for corresponding smooth tubes. Single-tube experiments with water indicate that at moderate velocities the tube-side coefficients are enhanced by a factor equal to the ratio of fluted-to-smooth surface areas while the fluid friction is similarly increased. The experimental data are transformed into mean individual coefficients for ammonia and water. Overall coefficients for a particular case are presented to illustrate the efficacy of enhancement by flutes on one or both sides of the heat transfer surface. Means are described for using emerging data to predict the static and dynamic behavior of the power cycle and the interactions of components throughout the complete power plant.

Rothfus, R.R.; Neuman, C.P.

1977-03-23T23:59:59.000Z

35

Thermodynamic Analysis of Combined Cycle District Heating System  

E-Print Network (OSTI)

This paper presents a thermodynamic analysis of the University of Massachusetts' Combined Heat and Power (CHP) District Heating System. Energy and exergy analyses are performed based on the first and second laws of thermodynamics for power generation systems that include a 10 MW Solar combustion gas turbine, a 4-MW steam turbine, a 100,000 pph heat recovery steam generator (HRSG), three 125,000 pph package boilers, and auxiliary equipment. In the analysis, actual system data is used to assess the district heating system performance, energy and exergy efficiencies, exergetic improvement potential and exergy losses. Energy and exergy calculations are conducted for the whole year on an hourly basis. System efficiencies are calculated for a wide range of component operating loads. The results show how thermodynamic analysis can be used to identify the magnitudes and location of energy losses in order to improve the existing system, processes or components.

Suresh, S.; Gopalakrishnan, H.; Kosanovic, D.

2011-01-01T23:59:59.000Z

36

Geothermal heat cycle research supercritical cycle with counterflow condenser in different orientations  

DOE Green Energy (OSTI)

The Heat Cycle Research Program, which is conducted for the Department of Energy, has as its objective the development of the technology for effecting the improved utilization of moderate temperature geothermal resources. The current testing involves the investigation of binary power cycle performance utilizing mixtures of non-adjacent hydrocarbons as the working fluids, with supercritical vaporization and in-tube condensation of the working fluid. The utilization of these concepts verified here will improve the net geofluid effectiveness (net watt hours plant output per pound of geofluid) about 20% over that of a conventional binary power plant. The major effect in this improvement is the ability to achieve integral, countercurrent condensation. Results are presented for the recent testing including those tests examining the performance of the countercurrent condenser at different tube inclinations and comparison with new design-base computer programs. 9 refs., 9 figs.

Bliem, C.J.; Mines, G.L.

1988-01-01T23:59:59.000Z

37

Life Cycle cost Analysis of Waste Heat Operated Absorption Cooling Systems for Building HVAC Applications  

E-Print Network (OSTI)

In this paper, life cycle cost analysis (LCCA) of waste heat operated vapour absorption air conditioning system (VARS) incorporated in a building cogeneration system is presented and discussed. The life cycle cost analysis (LCCA) based on present worth cost (PWC) method, which covers the initial costs, operating costs, maintenance costs, replacement costs and salvage values is the useful tool to merit various cooling and power generation systems for building applications. A life cycle of 23 years was used to calculate the PWC of the system for annual operating hours of 8760 and the same is compared with the electric based vapour compression chiller (VCRS) of same capacity. The life cycle cost (LCC) of waste heat operated absorption chiller is estimated to be US $ 1.5 million which is about 71.5 % low compared to electric powered conventional vapour compression chiller. From the analysis it was found that the initial cost of VARS system was 125 % higher than that of VCRS, while the PWC of operating cost of VARS was 78.2 % lower compared to VCRS. The result shows that the waste heat operated VARS would be preferable from the view point of operating cost and green house gas emission reduction.

Saravanan, R.; Murugavel, V.

2010-01-01T23:59:59.000Z

38

Annual Cycle of Temperature and Heat Storage in the World Ocean  

Science Conference Proceedings (OSTI)

The annual cycle of temperature and heat storage for the world ocean and individual ocean basins is described based on climatological monthly-mean temperature fields. One well-known feature observed in the fields of temperature and heat storage ...

Sydney Levitus

1984-04-01T23:59:59.000Z

39

Use of an open-cycle absorption system for heating and cooling  

DOE Green Energy (OSTI)

Solar cooling for commercial applications using open-cycle absorption refrigeration systems has been investigated and found to be feasible. If an open-cycle absorption system can be operated as a chemical heat pump for winter heating operation, the system would offer year-round operation that could make the system economically viable for many regions of the US. An analysis of heating operation for the open-cycle system is presented using a computer program that simulates heat and mass transfer processes for any environmental condition. The open-cycle absorption refrigeration system can be operated as a chemical heat pump. Simulations for winter heating operation were run for five US cities, with solar COP's in the range of .06 to .16. At these levels, the OCAR system can provide full heating and cooling operation for office buildings in many southern US cities.

Schlepp, D. R.; Collier, R. K.

1981-03-01T23:59:59.000Z

40

Dynamic modeling and multivariable control of organic Rankine cycles in waste heat utilizing processes  

Science Conference Proceedings (OSTI)

In this paper, the dynamics of organic Rankine cycles (ORCs) in waste heat utilizing processes is investigated, and the physical model of a 100 kW waste heat utilizing process is established. In order to achieve both transient performance and steady-state ... Keywords: Linear quadratic regulator, Organic Rankine cycles, Process control

Jianhua Zhang; Wenfang Zhang; Guolian Hou; Fang Fang

2012-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Research on optimization design of the heating/cooling channels for rapid heat cycle molding based on response surface methodology and constrained particle swarm optimization  

Science Conference Proceedings (OSTI)

The aim of this work is to optimize the layout of the heating/cooling channels for rapid heat cycle molding with hot medium heating and coolant cooling by using response surface methodology and optimization technique. By means of a Box-Behnken experiment ... Keywords: Injection molding, Particle swarm optimization (PSO), Rapid heat cycle molding (RHCM), Response surface methodology (RSM), Steam heating

Guilong Wang; Guoqun Zhao; Huiping Li; Yanjin Guan

2011-06-01T23:59:59.000Z

42

GasTurbine/Heat Recovery Steam Generator Cycle Alignment  

Science Conference Proceedings (OSTI)

The objectives of this report are to outline a procedure for identifying common opportunities for combined cycle plant performance improvement; to define a framework to analyze these performance opportunities; and to describe the application of this methodology to achieve improved base load performance and part load operability. This overall integrated approach to combined cycle plant performance analysis is referred to as cycle alignment.Three cases are described for potential combined ...

2012-12-20T23:59:59.000Z

43

Unique method for liquid nitrogen precooling of a plate fin heat exchanger in a helium refrigeration cycle  

E-Print Network (OSTI)

Unique method for liquid nitrogen precooling of a plate fin heat exchanger in a helium refrigeration cycle

Weber, T B; Howell, G; Racine, M; Weisend, J G

2004-01-01T23:59:59.000Z

44

EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF NEW POWER CYCLES AND ADVANCED FALLING FILM HEAT EXCHANGERS  

Science Conference Proceedings (OSTI)

The final report for the DOE/UNM grant number DE-FG26-98FT40148 discusses the accomplishments of both the theoretical analysis of advanced power cycles and experimental investigation of advanced falling film heat exchangers. This final report also includes the progress report for the third year (period of October 1, 2000 to September 30, 2001). Four new cycles were studied and two cycles were analyzed in detail based on the second law of thermodynamics. The first cycle uses a triple combined cycle, which consists of a topping cycle (Brayton/gas), an intermediate cycle (Rankine/steam), and a bottoming cycle (Rankine/ammonia). This cycle can produce high efficiency and reduces the irreversibility of the Heat Recovery Steam Generator (HRSC) of conventional combined power cycles. The effect of important system parameters on the irreversibility distribution of all components in the cycle under reasonable practical constraints was evaluated. The second cycle is a combined cycle, which consists of a topping cycle (Brayton/gas) and a bottoming cycle (Rankine/ammonia) with integrated compressor inlet air cooling. This innovative cycle can produce high power and efficiency. This cycle is also analyzed and optimized based on the second the second law to obtain the irreversibility distribution of all components in the cycle. The results of the studies have been published in peer reviewed journals and ASME conference proceeding. Experimental investigation of advanced falling film heat exchangers was conducted to find effective additives for steam condensation. Four additives have been selected and tested in a horizontal tube steam condensation facility. It has been observed that heat transfer additives have been shown to be an effective way to increase the efficiency of conventional tube bundle condenser heat exchangers. This increased condensation rate is due to the creation of a disturbance in the liquid condensate surround the film. The heat transfer through such a film has increased due to the onset of Maranogni convection as well as the population of ''dropwise-like'' condensation increased. The results have been published in peer reviewed journals.

Arsalan Razani; Kwang J. Kim

2001-12-01T23:59:59.000Z

45

Seasonal Cycle of the Mixed Layer Heat Budget in the Northeastern Tropical Atlantic Ocean  

Science Conference Proceedings (OSTI)

The seasonal cycle of the mixed layer heat budget in the northeastern tropical Atlantic (0°–25°N, 18°–28°W) is quantified using in situ and satellite measurements together with atmospheric reanalysis products. This region is characterized by ...

Gregory R. Foltz; Claudia Schmid; Rick Lumpkin

2013-10-01T23:59:59.000Z

46

The Organic Rankine Cycle System, Its Application to Extract Energy From Low Temperature Waste Heat  

E-Print Network (OSTI)

The conservation of energy by its recovery from low temperature waste heat is of increasing importance in today's world energy crisis. The Organic Rankine Cycle is a cost efficient and proven method of converting low temperature (200-400o F) waste heat to mechanical and/or electrical energy. Applying the Organic Rankine Cycle technology to typical liquid and mixed component condensing streams is described using actual examples. Selection of the organic working fluid is explored. The Rankine Cycle efficiency is directly dependent upon the temperature difference between its evaporating and condensing phases. The evaporating level is set by the heat source; therefore, to maximize efficiency, it is essential to obtain the lowest condensing temperature practical. Various condensing schemes are discussed emphasizing methods of optimizing the net output of the total system. Several Organic Rankine Cycle commercial applications are summarized with experience and general performance given. The economics and optimization techniques in typical applications including multiple heat sources are discussed.

Sawyer, R. H.; Ichikawa, S.

1980-01-01T23:59:59.000Z

47

The Annual Cycle of Heat Content in the Peru Current Region  

Science Conference Proceedings (OSTI)

The relative importance of the processes responsible for the annual cycle in the upper-ocean heat content in the Peru Current, in the southeastern tropical Pacific, was diagnosed from an oceanic analysis dataset. It was found that the annual ...

Ken Takahashi

2005-12-01T23:59:59.000Z

48

Generation Maintenance Application Center: Combustion Turbine Combined-Cycle Heat Recovery Steam Generator Maintenance Guide  

Science Conference Proceedings (OSTI)

This guide provides information to assist personnel involved with the maintenance of the heat recovery steam generator at a combustion gas turbine combined cycle facility, including good maintenance practices, preventive maintenance techniques and troubleshooting guidance. BackgroundCombustion turbine combined cycle (CTCC) facilities utilize various components that can be unique to this particular type of power plant. As such, owners and ...

2013-05-15T23:59:59.000Z

49

RANKINE CYCLE WASTE HEAT RECOVERY SYSTEM - Energy Innovation Portal  

This disclosure relates to a waste heat recovery (WHR) system and to a system and method for regulation of a fluid inventory in a condenser and a receiver of a ...

50

Characteristics of the Limit Cycle of a Reciprocating Quantum Heat Engine  

E-Print Network (OSTI)

When a reciprocating heat engine is started it eventually settles to a stable mode of operation. The approach of a first principle quantum heat engine toward this stable limit cycle is studied. The engine is based on a working medium consisting of an ensemble of quantum systems composed of two coupled spins. A four stroke cycle of operation is studied, with two {\\em isochore} branches where heat is transferred from the hot/cold baths and two {\\em adiabats} where work is exchanged. The dynamics is generated by a completely positive map. It has been shown that the performance of this model resembles an engine with intrinsic friction. The quantum conditional entropy is employed to prove the monotonic approach to a limit cycle. Other convex measures, such as the quantum distance display the same monotonic approach. The equations of motion of the engine are solved for the different branches and are combined to a global propagator that relates the state of the engine in the beginning of the cycle to the state after one period of operation of the cycle. The eigenvalues of the propagator define the rate of relaxation toward the limit cycle. A longitudinal and transverse mode of approach to the limit cycle is identified. The entropy balance is used to explore the necessary conditions which lead to a stable limit cycle. The phenomena of friction can be identified with a zero change in the von Neumann entropy of the working medium.

Tova Feldmann; Ronnie Kosloff

2004-05-28T23:59:59.000Z

51

The Design of an Open Rankine-Cycle Industrial Heat Pump  

E-Print Network (OSTI)

An open Rankine-cycle heat pump is ideally suited for producing low-pressure industrial process steam. Because steam serves as both the heat pump motive fluid and process fluid, the system achieves a unique simplicity and versatility. No intermediate refrigerant fluid exists for which to construct a process interface or impose a temperature limit. Interface components such as the heat pump condenser are not required. Moreover, the use of water vapor eliminates toxicity and flammability risks inherent with most closed-cycle heat pump fluids. The control strategy is simple. Low-pressure (subatmospheric) water vapor, generated by flashing steam at a temperature below that of the waste stream, is compressed to the process pressure and temperature by an electric-motor-driven, multistage compressor train. This strategy permits the heat pump to accommodate upsets such as sudden changes in the waste stream flow and/or temperature, as well as fluctuation within the process stream.

Leibowitz, H. M.; Chaudoir, D. W.

1981-01-01T23:59:59.000Z

52

Multi-heat source thermodynamic cycles and demonstrations of their power plants  

SciTech Connect

Being on the analysis of the requirements and the problems existing in the thermodynamic cycles (TC) and their power plants (PPs) using single heat source (SHS) of moderate and low grade, the paper puts forward the theory of electricity generation by using multi-heat sources (MHS), its possibility and advantages of these heat sources (HSs). Proposals of two types of MHS combination cycles, such as solar thermal energy (STE) and geothermal energy (GE), solar-geothermal and fuel burning energy (FBE) or waste heat (WH) are given. The calculation results of these PPs and their corresponding SHS-PPs are listed. MHS-PPs are superior from both technical and economic points of view.

Dai-Ji, H.

1984-08-01T23:59:59.000Z

53

An assessment of the performance of closed cycles with and without heat rejection at cryogenic temperatures  

Science Conference Proceedings (OSTI)

This paper presents optimized cycle performance that can be obtained with systems including a closed cycle gas turbine (CCGT). The influence of maximum temperature, minimum temperature, and recuperator effectiveness on cycle performance is illustrated. Several power-plant arrangements are analyzed and compared based on thermodynamic performance (thermal efficiency and specific work); enabling technologies (available at present); and developing technologies (available in the near term of future). The work includes the effects of utilization of high temperature ceramic heat exchangers and of coupling of CCGT systems with plants vaporizing liquid hydrogen (LH{sub 2}) or liquefied natural gas (LNG). Given the versatility of energy addition and rejection sources that can be utilized in closed gas-cycle systems, the thermodynamic performance of power plants shown in this paper indicate the remarkable capabilities and possibilities for closed gas-cycle systems.

Agazzani, A.; Massardo, A.F. [Univ. of Genova (Italy). Ist. di Macchine e Sistemi Energetici; Korakianitis, T. [Washington Univ., St. Louis, MO (United States)

1999-07-01T23:59:59.000Z

54

Modeling and optimization of a combined cycle Stirling-ORC system and design of an integrated microchannel Stirling heat rejector.  

E-Print Network (OSTI)

??The performance of a combined Stirling-ORC power cycle is evaluated, and an integrated microchannel heat exchanger is designed as an annular cold-side heat rejector for… (more)

[No author

2010-01-01T23:59:59.000Z

55

EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF NEW POWER CYCLES AND ADVANCED FALLING FILM HEAT EXCHANGERS  

SciTech Connect

The annual progress report for the period of October 1, 1999 to September 30, 2000 on DOE/UNM grant number DE-FG26-98FT40148 discusses the progress on both the theoretical analysis of advanced power cycles and the experimental investigation of advanced falling film heat exchangers. The previously developed computer program for the triple cycle, based on the air standard cycle assumption, was modified to include actual air composition (%77.48 N{sub 2}, %20.59 O{sub 2}, %1.9 H{sub 2}O, and %0.03 CO{sub 2}). The actual combustion products were used in exergy analysis of the triple cycle. The effect of steam injection into the combustion chamber on its irreversibility, and the irreversibility of the entire cycle, was evaluated. A more practical fuel inlet condition and a better position of the feedwater heater in the steam cycle were used in the modified cycle. The effect of pinch point and the temperature difference between the combustion products, as well as the steam in the heat recovery steam generator on irreversibility of the cycle were evaluated. Design, construction, and testing of the multitube horizontal falling film condenser facility were completed. Two effective heat transfer additives (2-ethyl-1-hexanol and alkyl amine) were identified and tested for steam condensation. The test results are included. The condenser was designed with twelve tubes in an array of three horizontals and four verticals, with a 2-inch horizontal and 1.5-inch vertical in-line pitch. By using effective additives, the condensation heat transfer rate can be augmented as much as 30%, as compared to a heat transfer that operated without additives under the same operating condition. When heat transfer additives function effectively, the condensate-droplets become more dispersed and have a smaller shape than those produced without additives. These droplets, unlike traditional turbulence, start at the top portion of the condenser tubes and cover most of the tubes. Such a flow behavior can be explained by the Marangoni effect (in terms of thermodynamic equilibrium) in connection with obtained surface tension data. In our experiments, we noted that the use of heat transfer additives such as 2-ethyl-1-hexanol for steam condensation was highly effective.

Arsalan Razani; Kwang J. Kim

2000-10-28T23:59:59.000Z

56

Heat Recovery Steam Generators for Combined Cycle Applications: HRSG Procurement, Design, Construction, and Operation Update  

Science Conference Proceedings (OSTI)

Design alternatives and procurement approaches for heat recovery steam generators, supplemental firing duct burners, and ancillary steam systems are addressed in this report. Power engineers and project developers will find an up-to-date, comprehensive resource for planning, specification and preliminary design in support of combined cycle plant development.

2005-03-29T23:59:59.000Z

57

Final Report. Conversion of Low Temperature Waste Heat Utilizing Hermetic Organic Rankine Cycle  

SciTech Connect

The design of waste heat recovery using the organic Rankine cycle (ORC) engine is updated. Advances in power electronics with lower cost enable the use of a single shaft, high-speed generator eliminating wear items and allowing hermetic sealing of the working fluid. This allows maintenance free operation and a compact configuration that lowers cost, enabling new market opportunities.

Fuller, Robert L.

2005-04-20T23:59:59.000Z

58

Characteristics of the Limit Cycle of a Reciprocating Quantum Heat Engine  

E-Print Network (OSTI)

When a reciprocating heat engine is started it eventually settles to a stable mode of operation. The approach of a first principle quantum heat engine toward this stable limit cycle is studied. The engine is based on a working medium consisting of an ensemble of quantum systems composed of two coupled spins. A four stroke cycle of operation is studied, with two {\\em isochore} branches where heat is transferred from the hot/cold baths and two {\\em adiabats} where work is exchanged. The dynamics is generated by a completely positive map. It has been shown that the performance of this model resembles an engine with intrinsic friction. The quantum conditional entropy is employed to prove the monotonic approach to a limit cycle. Other convex measures, such as the quantum distance display the same monotonic approach. The equations of motion of the engine are solved for the different branches and are combined to a global propagator that relates the state of the engine in the beginning of the cycle to the state after...

Feldmann, T; Feldmann, Tova; Kosloff, Ronnie

2004-01-01T23:59:59.000Z

59

Solar Thermochemical Fuels Production: Solar Fuels via Partial Redox Cycles with Heat Recovery  

SciTech Connect

HEATS Project: The University of Minnesota is developing a solar thermochemical reactor that will efficiently produce fuel from sunlight, using solar energy to produce heat to break chemical bonds. The University of Minnesota is envisioning producing the fuel by using partial redox cycles and ceria-based reactive materials. The team will achieve unprecedented solar-to-fuel conversion efficiencies of more than 10% (where current state-of-the-art efficiency is 1%) by combined efforts and innovations in material development, and reactor design with effective heat recovery mechanisms and demonstration. This new technology will allow for the effective use of vast domestic solar resources to produce precursors to synthetic fuels that could replace gasoline.

None

2011-12-19T23:59:59.000Z

60

Analysis of community solar systems for combined space and domestic hot water heating using annual cycle thermal energy storage  

DOE Green Energy (OSTI)

A simplified design procedure is examined for estimating the storage capacity and collector area for annual-cycle-storage, community solar heating systems in which 100% of the annual space heating energy demand is provided from the solar source for the typical meteorological year. Hourly computer simulations of the performance of these systems were carried out for 10 cities in the United States for 3 different building types and 4 community sizes. These permitted the use of design values for evaluation of a more simplified system sizing method. Results of this study show a strong correlation between annual collector efficiency and two major, location-specific, annual weather parameters: the mean air temperature during daylignt hours and the total global insolation on the collector surface. Storage capacity correlates well with the net winter load, which is a measure of the seasonal variation in the total load, a correlation which appears to be independent of collector type.

Hooper, F.C.; McClenahan, J.D.; Cook, J.D.; Baylin, F.; Monte, R.; Sillman, S.

1980-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

HTGR-GT closed-cycle gas turbine: a plant concept with inherent cogeneration (power plus heat production) capability  

SciTech Connect

The high-grade sensible heat rejection characteristic of the high-temperature gas-cooled reactor-gas turbine (HTGR-GT) plant is ideally suited to cogeneration. Cogeneration in this nuclear closed-cycle plant could include (1) bottoming Rankine cycle, (2) hot water or process steam production, (3) desalination, and (4) urban and industrial district heating. This paper discusses the HTGR-GT plant thermodynamic cycles, design features, and potential applications for the cogeneration operation modes. This paper concludes that the HTGR-GT plant, which can potentially approach a 50% overall efficiency in a combined cycle mode, can significantly aid national energy goals, particularly resource conservation.

McDonald, C.F.

1980-04-01T23:59:59.000Z

62

Cycle Chemistry Guidelines for Shutdown, Layup, and Startup of Combined Cycle Units with Heat Recovery Steam Generators  

Science Conference Proceedings (OSTI)

Complete optimization of cycle chemistry in a combined-cycle unit requires more than proper selection and optimization of operating chemistry. Protection of the steam-water cycle also is essential during shutdown, layup, and startup phases. These guidelines consider protection of steam- and water-touched components at these times, consistent with the operating cycle chemistries in use.

2006-03-21T23:59:59.000Z

63

Rankine cycle energy conversion system design considerations for low and intermediate temperature sensible heat sources. Geothermal, waste heat, and solar thermal conversion  

DOE Green Energy (OSTI)

Design considerations are described for energy conversion systems for low and intermediate temperature sensible heat sources such as found in geothermal, waste heat, and solar-thermal applications. It is concluded that the most cost effective designs for the applications studied did not require the most efficient thermodynamic cycle, but that the efficiency of the energy conversion hardware can be a key factor.

Abbin, J.P. Jr.

1976-10-01T23:59:59.000Z

64

Use of oxides in thermochemical water-splitting cycles for solar heat sources. Copper oxides  

DOE Green Energy (OSTI)

Several oxides can be decomposed to oxygen and a lower oxide at temperatures that might be feasible with a solar heat source. Heat might be directly transmitted to the solid through an air window, rather than quartz, with release of oxygen to the atmosphere. The cycle utilizing CuO, I/sub 2/, and Mg (OH)/sub 2/ is similar to the previous Co/sub 3/O/sub 4/ - CoO cycle. We are concentrating on the reformation of CuO. At 448 K the rate is favorable; for example, the yield rises about linearly with time to 92% at 1.17 h and more slowly thereafter. The only difficulty is the formation of CuI as a metastable intermediate. The oxidation of CuI is thermodynamically very favorable, but its rate limits completion. Excess Mg(OH)/sub 2/ appears to increase the rate but not to the point where IO/sub 3//sup -/ oxidation of CuI competes with oxidation of Cu/sub 2/O. Nevertheless, the batch runs suggest that about 98% of the maximum possible MgI/sub 2/ could be formed. Cuprous iodide complexes formed in the concentrated MgI/sub 2/ may give the necessary improvement by providing a solution path for their oxidation by iodate. Work of others pertaining to the cycle is briefly discussed.

Jones, W.M.; Bowman, M.G.

1984-01-01T23:59:59.000Z

65

Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients  

DOE Green Energy (OSTI)

Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients Dan Wendt, Greg Mines Idaho National Laboratory The use of mixed working fluids in binary power plants can provide significant increases in plant performance, provided the heat exchangers are designed to take advantage of these fluids non-isothermal phase changes. In the 1980's testing was conducted at DOE's Heat Cycle Research Facility (HCRF) where mixtures of different compositions were vaporized at supercritical pressures and then condensed. This testing had focused on using the data collected to verify that Heat Transfer Research Incorporated (HTRI) codes were suitable for the design of heat exchangers that could be used with mixtures. The HCRF data includes mixture compositions varying from 0% to 40% isopentane and condenser tube orientations of 15{sup o}, 60{sup o}, and 90{sup o} from horizontal. Testing was performed over a range of working fluid and cooling fluid conditions. Though the condenser used in this testing was water cooled, the working fluid condensation occurred on the tube-side of the heat exchanger. This tube-side condensation is analogous to that in an air-cooled condenser. Tube-side condensing heat transfer coefficient information gleaned from the HCRF testing is used in this study to assess the suitability of air-cooled condenser designs for use with mixtures. Results of an air-cooled binary plant process model performed with Aspen Plus indicate that that the optimal mixture composition (producing the maximum net power for the scenario considered) is within the range of compositions for which data exist. The HCRF data is used to assess the impact of composition, tube orientation, and process parameters on the condensing heat transfer coefficients. The sensitivity of the condensing coefficients to these factors is evaluated and the suitability of air-cooled condenser designs with mixtures is assessed. This paper summarizes the evaluation of the HCRF data and discusses the next steps in the project evaluation of air-cooled condenser designs that can take advantage of the performance gains possible with these fluids.

Dan Wendt; Greg Mines

2011-10-01T23:59:59.000Z

66

Thermal cycling effect on the nanoparticle distribution and specific heat of a carbonate eutectic with alumina nanoparticles  

E-Print Network (OSTI)

The objective of this research was to measure the effect of thermal cycling on the nanoparticle distribution and specific heat of a nanocomposite material consisting of a eutectic of lithium carbonate and potassium carbonate and 1% by mass alumina nanoparticles. The material was subjected to thermal cycling in a stainless steel tube using a temperature controlled furnace. After thermal cycling, the stainless steel tube was sectioned into three equal parts – top, middle and bottom. Composite material samples were taken from the central region and near the wall region of each section. The specific heat of this material in the temperature range of 290°C-397°C was measured using the Modulated Differential Scanning Calorimeter (MDSC) method. The concentration of alumina nanoparticles in this material was measured using neutron activation analysis. The average specific heat of the uncycled material was found to be 1.37 J/g°C.The average specific heat of the thermally cycled material was between 1.7-2.1 J/g°C. It was found that the concentration of the nanoparticle varied along the height of the sample tube. The nanoparticles tended to settle towards the bottom of the tube with thermal cycling. There was also migration of nanoparticles towards the wall of the sample tube with thermal cycling. Despite these gross movements of nanoparticles, there was no significant change in the specific heat of the nanocomposite due to thermal cycling.

Shankar, Sandhya

2011-05-01T23:59:59.000Z

67

Draft report: application of organic Rankine cycle heat recovery systems to diesel powered marine vessels  

DOE Green Energy (OSTI)

The analysis and results of an investigation of the application of organic Rankine cycle heat recovery systems to diesel-powered marine vessels are described. The program under which this study was conducted was sponsored jointly by the US Energy Research and Development Administration, the US Navy, and the US Maritime Administration. The overall objective of this study was to investigate diesel bottoming energy recovery systems, currently under development by three US concerns, to determine the potential for application to marine diesel propulsion and auxiliary systems. The study primarily focused on identifying the most promising vessel applications (considering vessel type, size, population density, operational duty cycle, etc.) so the relative economic and fuel conservation merits of energy recovery systems could be determined and assessed. Vessels in the current fleet and the projected 1985 fleet rated at 1000 BHP class and above were investigated.

Not Available

1977-07-15T23:59:59.000Z

68

Proceedings: Ninth International Conference on Cycle Chemistry in Fossil and Combined Cycle Plants with Heat Recovery Steam Generators  

Science Conference Proceedings (OSTI)

Proper selection, application, and optimization of cycle chemistry have long been recognized as integral to ensuring the highest possible levels of component availability and reliability in fossil-fired generating plant units. These proceedings of the Ninth EPRI International Conference on Cycle Chemistry in Fossil Plants address state-of-the-art practices in conventional and combined-cycle plants. The content provides a worldwide perspective on cycle chemistry practices and insight on industry issues an...

2010-01-22T23:59:59.000Z

69

Consumer life-cycle cost impacts of energy-efficiency standards for residential-type central air conditioners and heat pumps  

SciTech Connect

In support of the federal government's efforts to raise the minimum energy-efficiency standards for residential-type central air conditioners and heat pumps, a consumer life-cycle cost (LCC) analysis was conducted to demonstrate the economic impacts on individual consumers from revisions to the standards. LCC is the consumer's cost of purchasing and installing an air conditioner or heat pump and operating the unit over its lifetime. The LCC analysis is conducted on a nationally representative sample of air conditioner and heat pump consumers resulting in a distribution of LCC impacts showing the percentage of consumers that are either benefiting or being burdened by increased standards. Relative to the existing minimum efficiency standard of 10 SEER, the results show that a majority of split system air conditioner and heat pump consumers will either benefit or be insignificantly impacted by increased efficiency standards of up to 13 SEER.

Rosenquist, Gregory; Chan, Peter; Lekov, Alex; McMahon, James; Van Buskirk, Robert

2001-10-10T23:59:59.000Z

70

Extended Coronal Heating and Solar Wind Acceleration Over the Solar Cycle  

E-Print Network (OSTI)

This paper reviews our growing understanding of the physics behind coronal heating (in open-field regions) and the acceleration of the solar wind. Many new insights have come from the last solar cycle's worth of observations and theoretical work. Measurements of the plasma properties in the extended corona, where the primary solar wind acceleration occurs, have been key to discriminating between competing theories. We describe how UVCS/SOHO measurements of coronal holes and streamers over the last 14 years have provided clues about the detailed kinetic processes that energize both fast and slow wind regions. We also present a brief survey of current ideas involving the coronal source regions of fast and slow wind streams, and how these change over the solar cycle. These source regions are discussed in the context of recent theoretical models (based on Alfven waves and MHD turbulence) that have begun to successfully predict both the heating and acceleration in fast and slow wind regions with essentially no fre...

Cranmer, Steven R; Miralles, Mari Paz; van Ballegooijen, Adriaan A

2010-01-01T23:59:59.000Z

71

Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model  

SciTech Connect

This study explores the impact of wastes generated from potential future fuel cycles and the issues presented by classifying these under current classification criteria, and discusses the possibility of a comprehensive and consistent characteristics-based classification framework based on new waste streams created from advanced fuel cycles. A static mass flow model, Fuel-Cycle Integration and Tradeoffs (FIT), was used to calculate the composition of waste streams resulting from different nuclear fuel cycle choices. This analysis focuses on the impact of waste form heat load on waste classification practices, although classifying by metrics of radiotoxicity, mass, and volume is also possible. The value of separation of heat-generating fission products and actinides in different fuel cycles is discussed. It was shown that the benefits of reducing the short-term fission-product heat load of waste destined for geologic disposal are neglected under the current source-based radioactive waste classification system , and that it is useful to classify waste streams based on how favorable the impact of interim storage is in increasing repository capacity.

Denia Djokic; Steven J. Piet; Layne F. Pincock; Nick R. Soelberg

2013-02-01T23:59:59.000Z

72

Simulation and performance analysis of an ammonia-water absorption heat pump based on the generator-absorber heat exchange (GAX) cycle  

Science Conference Proceedings (OSTI)

A computer simulation has been conducted to investigate the performance of an absorption heat pump, based on the Generator-Absorber Heat Exchange (GAX) cycle employing ammonia-water as the working fluid pair. The particular feature of this cycle is the ability to recover heat from the absorber and employ it to partially heat the generator, thus improving the COP. In the present study, a detailed simulation has been conducted of one of the preferred configurations for the cycle. A modular computer code for flexible simulation of absorption systems (ABSIM) was employed. Performance parameters, including COP and capacity, were investigated as functions of different operating parameters over a wide range of conditions in both the cooling and heating mode. The effect of the ambient temperature, the rectifier performance, the flowrate in the GAX heat transfer loop and the refrigerant flow control were investigated. COP`s on the order of 1.0 for cooling and 2.0 for heating have been calculated.

Grossman, G. [Israel Institute of Technology, Haifa (Israel); DeVault, R.C.; Creswick, F.A. [Oak Ridge National Lab., TN (United States)

1995-02-01T23:59:59.000Z

73

Economic analysis of community solar heating systems that use annual cycle thermal energy storage  

DOE Green Energy (OSTI)

The economics of community-scale solar systems that incorporate a centralized annual cycle thermal energy storage (ACTES) coupled to a distribution system is examined. Systems were sized for three housing configurations: single-unit dwellings, 10-unit, and 200-unit apartment complexes in 50-, 200-, 400-, and 1000-unit communities in 10 geographic locations in the United States. Thermal energy is stored in large, constructed, underground tanks. Costs were assigned to each component of every system in order to allow calculation of total costs. Results are presented as normalized system costs per unit of heat delivered per building unit. These methods allow: (1) identification of the relative importance of each system component in the overall cost; and (2) identification of the key variables that determine the optimum sizing of a district solar heating system. In more northerly locations, collectors are a larger component of cost. In southern locations, distribution networks are a larger proportion of total cost. Larger, more compact buildings are, in general, less expensive to heat. For the two smaller-scale building configurations, a broad minima in total costs versus system size is often observed.

Baylin, F.; Monte, R.; Sillman, S.; Hooper, F.C.; McClenahan, J.D.

1981-02-01T23:59:59.000Z

74

Heat recovery steam generator outlet temperature control system for a combined cycle power plant  

Science Conference Proceedings (OSTI)

This patent describes a command cycle electrical power plant including: a steam turbine and at least one set comprising a gas turbine, an afterburner and a heat recovery steam generator having an attemperator for supplying from an outlet thereof to the steam turbine superheated steam under steam turbine operating conditions requiring predetermined superheated steam temperature, flow and pressure; with the gas turbine and steam turbine each generating megawatts in accordance with a plant load demand; master control means being provided for controlling the steam turbine and the heat recovery steam generator so as to establish the steam operating conditions; the combination of: first control means responsive to the gas inlet temperature of the heat recovery steam generator and to the plant load demand for controlling the firing of the afterburner; second control means responsive to the superheated steam predetermined temperature and to superheated steam temperature from the outlet for controlling the attemperator between a closed and an open position; the first and second control means being operated concurrently to maintain the superheated steam outlet temperature while controlling the load of the gas turbine independently of the steam turbine operating conditions.

Martens, A.; Myers, G.A.; McCarty, W.L.; Wescott, K.R.

1986-04-01T23:59:59.000Z

75

Organic Rankine Cycle Systems for Waste Heat Recovery in Refineries and Chemical Process Plants  

E-Print Network (OSTI)

The design of a low temperature Rankine cycle system using R-113 working fluid for recovery and conversion of process waste heat is described for typical applications in oil refineries and chemical plants. The system is designed to produce electric power from waste heat available in a temperature range from 180oF to 400oF. The design of a new ORC turbo generator uniquely adapted to applications of this type is presented. The unit has been designed for power outputs from 3/4 to 2 1/2 MW and turbine inlet temperatures from 170 to 260oF. The machine design has eliminated the need for shaft seals, shaft couplings and the usual lube oil console normally required for turbine-generator units. Results of prototype tests of a 1 MW unit are presented. A product package and recommended division of responsibilities between purchaser, A&E company and supplier is presented for installations in refineries and process plants. The product package covers the electrical power range from 3/4 to 5 MW and waste heat streams from 20 to 130 million BTU/hr.

Meacher, J. S.

1981-01-01T23:59:59.000Z

76

Combined cycle and waste heat recovery power systems based on a novel thermodynamic energy cycle utilizing low-temperature heat for power generation  

SciTech Connect

A new thermodynamic energy cycle has been developed, using a multicomponent working agent. Condensation is supplemented with absorption, following expansion in the turbine. Several combined power systems based on this cycle have been designed and cost-estimated. Efficiencies of these new systems are 1.35 to 1.5 times higher than the best Rankine Cycle system, at the same border conditions. Investment cost per unit of power output is about two-thirds of the cost of a comparable Rankine Cycle system. Results make cogeneration economically attractive at current energy prices. The first experimental installation is planned by Fayette Manufacturing Company and Detroit Diesel Allison Division of General Motors.

Kalina, A.I.

1983-01-01T23:59:59.000Z

77

Open-cycle chemical heat pump and energy storage system. Final report of Research Program, June 1982-September 1983  

DOE Green Energy (OSTI)

A liquid desiccant heat pump that can heat, cool, humidify, and dehumidify, as well as heat domestic water, has been designed, developed, and tested over a six-year period. Successful operation of the machine demonstrated that a heating cycle utilizing the heat of sorption of a desiccant solution could be added to a desiccant cooling system, thus creating an open-cycle liquid desiccant heat pump. The liquid system was shown to possess a unique capability: the ability to store energy, not as sensible heat but as chemical potential energy, in an uninsulated storage tank with a volume that is an order of magnitude smaller than the insulated volumes needed for water or rock bed storage systems. The spent absorbent solution was reconcentrated in a roof-top solar-collector/reconcentrator. Additionally, it was shown that a packed-column could also act as the reconcentrator; for this operation, the desiccant solution was heated by flat-plate solar collectors, by off-peak electricity, and by waste heat from a vapor compressor.

Robison, H.I.

1983-10-01T23:59:59.000Z

78

Application of direct contact heat exchangers to geothermal power production cycles. Project review, December 1, 1974--May 31, 1977  

DOE Green Energy (OSTI)

Work performed on the development of direct contact heat exchanger power cycles for geothermal applications is reviewed. The period covered in the report is from the inception of the project in 1974 through May 31, 1977. Results from a large experimental program on heat exchanger develpment as well as from many analyses of components and cycle performance and economics are given. A number of working fluids and operating conditions have been considered, and no major obstacles for the implementation of the concept have been discovered.

Jacobs, H.R.; Boehm, R.F.; Hansen, A.C.

1977-01-01T23:59:59.000Z

79

Waste Heat Energy Harvesting Using Olsen Cycle on PZN-5.5PT Single Crystals  

E-Print Network (OSTI)

energy converter for waste heat energy harvesting using co-L. “Pyroelectric waste heat energy harvesting using heatNo.3, pp.035015, 2012. WASTE HEAT ENERGY HARVESTING USING

McKinley, Ian Meeker; Kandilian, Razmig; Pilon, Laurent

2012-01-01T23:59:59.000Z

80

Nexant Parabolic Trough Solar Power Plant Systems Analysis; Task 2: Comparison of Wet and Dry Rankine Cycle Heat Rejection, 20 January 2005 - 31 December 2005  

DOE Green Energy (OSTI)

Subcontract report by Nexant, Inc., regarding a system analysis comparing solar parabolic trough plants with wet and dry rankine cycle heat rejection.

Kelly, B.

2006-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Life cycle assessment of an energy-system with a superheated steam dryer integrated in a local district heat and power plant  

SciTech Connect

Life cycle assessment (LCA) is a method for analyzing and assessing the environmental impact of a material, product or service throughout the entire life cycle. In this study 100 GWh heat is to be demanded by a local heat district. A mixture of coal and wet biofuel is frequently used as fuel for steam generation (Case 1). A conversion of the mixed fuel to dried biofuel is proposed. In the district it is also estimated that it is possible for 4000 private houses to convert from oil to wood pellets. It is proposed that sustainable solution to the actual problem is to combine heat and power production together with an improvement in the quality of wood residues and manufacture of pellets. It is also proposed that a steam dryer is integrated to the system (Case 2). Most of the heat from the drying process is used by the municipal heating networks. In this study the environmental impact of the two cases is examined with LCA. Different valuation methods shows the Case 2 is an improvement over Case 1, but there is diversity in the magnitudes of environmental impact in the comparison of the cases. The differences depend particularly on how the emissions of CO{sub 2}, NO{sub x} and hydrocarbons are estimated. The impact of the organic compounds from the exhaust gas during the drying is estimated as low in all of the three used methods.

Bjoerk, H.; Rasmuson, A. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Chemical Engineering Design

1999-07-01T23:59:59.000Z

82

Diagnostic/Troubleshooting Monitoring to Identify Damaging Cycle Chemistry or Thermal Transients in Heat Recovery Steam Generator Pressure Parts  

Science Conference Proceedings (OSTI)

The worldwide fleet of combined cycle units with heat recovery steam generators (HRSGs) has exhibited a disappointing track record with respect to reliability and availability in terms of HRSG tube failures (HTFs). This report will assist operators in identifying the harmful chemical and thermal transient excursions that lead to failure.

2005-03-07T23:59:59.000Z

83

Theoretical thermodynamic analysis of a closed-cycle process for the conversion of heat into electrical energy by means of a distiller and an electrochemical cell  

E-Print Network (OSTI)

We analyse a device aimed at the conversion of heat into electrical energy, based on a closed cycle in which a distiller generates two solutions at different concentrations, and an electrochemical cell consumes the concentration difference, converting it into electrical current. We first study an ideal model of such a process. We show that, if the device works at a single fixed pressure (i.e. with a "single effect"), then the efficiency of the conversion of heat into electrical power has an upper bound, given by the efficiency of a reversible Carnot engine operating between the boiling temperatures of the concentrated solution and of the pure solvent. When two heat reservoirs with a higher temperature difference are available, the overall efficiency can be incremented by employing an arrangement of multiple cells working at different pressures ("multiple effects"). We find that a given efficiency can be achieved with a reduced number of effects by using solutions with a high boiling point elevation.

Carati, Andrea; Brogioli, Doriano

2013-01-01T23:59:59.000Z

84

Heat exchanger temperature response for duty-cycle transients in the NGNP/HTE.  

SciTech Connect

Control system studies were performed for the Next Generation Nuclear Plant (NGNP) interfaced to the High Temperature Electrolysis (HTE) plant. Temperature change and associated thermal stresses are important factors in determining plant lifetime. In the NGNP the design objective of a 40 year lifetime for the Intermediate Heat Exchanger (IHX) in particular is seen as a challenge. A control system was designed to minimize temperature changes in the IHX and more generally at all high-temperature locations in the plant for duty-cycle transients. In the NGNP this includes structures at the reactor outlet and at the inlet to the turbine. This problem was approached by identifying those high-level factors that determine temperature rates of change. First are the set of duty cycle transients over which the control engineer has little control but which none-the-less must be addressed. Second is the partitioning of the temperature response into a quasi-static component and a transient component. These two components are largely independent of each other and when addressed as such greater understanding of temperature change mechanisms and how to deal with them is achieved. Third is the manner in which energy and mass flow rates are managed. Generally one aims for a temperature distribution that minimizes spatial non-uniformity of thermal expansion in a component with time. This is can be achieved by maintaining a fixed spatial temperature distribution in a component during transients. A general rule of thumb for heat exchangers is to maintain flow rate proportional to thermal power. Additionally the product of instantaneous flow rate and heat capacity should be maintained the same on both sides of the heat exchanger. Fourth inherent mechanisms for stable behavior should not be compromised by active controllers that can introduce new feedback paths and potentially create under-damped response. Applications of these principles to the development of a plant control strategy for the reference NGNP/HTE plant can be found in the body of this report. The outcome is an integrated plant/control system design. The following conclusions are drawn from the analysis: (1) The plant load schedule can be managed to maintain near-constant hot side temperatures over the load range in both the nuclear and chemical plant. (2) The reactor open-loop response is inherently stable resulting mainly from a large Doppler temperature coefficient compared to the other reactivity temperature feedbacks. (3) The typical controller used to manage reactor power production to maintain reactor outlet temperature at a setpoint introduces a feedback path that tends to destabilize reactor power production in the NGNP. (4) A primary loop flow controller that forces primary flow to track PCU flow rate is effective in minimizing spatial temperature differentials within the IHX. (5) Inventory control in both the primary and PCU system during ramp load change transients is an effective means of maintaining high NGNP thermal efficiency while at reduced electric load. (6) Turbine bypass control is an effective means for responding to step changes in generator load when equipment capacity limitations prevent inventory control from being effective. (7) Turbine bypass control is effective in limiting PCU shaft over speed for the loss of generator load upset event. (8) The proposed control strategy is effective in limiting time variation of the differential spatial temperature distribution in the IHX during transients. Essentially the IHX can be made to behave in a manner where each point in the IHX experiences approximately the same temperature rate of change during a transient. (9) The stability of the closed-loop Brayton cycle was found to be sensitive to where one operates on the turbo-machine performance maps. There are competing interests: more stable operation means operating on the curves at points that reduce overall cycle efficiency. Future work should address in greater detail elements that came to light in the course of this work. Specifically: (1) A stability analysi

Vilim, R. B.; Nuclear Engineering Division

2009-03-12T23:59:59.000Z

85

Procedure for Applying an Open-Cycle Heat Pump to An Existing Evaporator  

E-Print Network (OSTI)

An open-cycle heat pump, or mechanical vapor compression (MVC) system, is often an attractive technique for increasing the energy efficiency of an evaporator. With proper design, an MVC system is capable of dramatic cost savings when retrofitted to an existing evaporator. This is especially true if the evaporator is a single or double effect design. Many such evaporators were built when energy was cheap, or because a particular process is not amenable to modern designs incorporating many effects. Advances in compressor design have made MVC applicable to a broader range of processes than ever before. This paper discusses the basic steps required to apply MVC as a retrofit to an existing evaporator. Because of their importance to identification of candidate applications, this paper emphasizes the preliminary analysis and premonitoring steps. For illustration purposes the authors refer to an MVC retrofit in progress at a plant operated by Kraft, Inc. The project is cofunded by the New York State Energy Research and Development Authority (Albany, NY), and will serve as a demonstration site to facilitate increased adoption of MVC by other industrial firms.

Wagner, J. R.; Brush, F. C.

1984-01-01T23:59:59.000Z

86

Preliminary market analysis for Brayton cycle heat recovery system characterization program. Subtask 5. 2 of phase I program plan  

Science Conference Proceedings (OSTI)

The purpose of the task is to determine the market potential of the Brayton-cycle Subatmospheric System (SAS), especially as applied to the glass processing industry. Areas which impact the sales of the Brayton-cycle systems examined are: market size; opportunities for waste heat system installation (furnace rebuild and repair); pollution control on glass furnaces; equipment costs; equipment performance; and market growth potential. Supporting data were compiled for the glass industry inventory and are presented in Appendix A. Emission control techniques in the glass industry are discussed in Appendix B. (MCW)

Not Available

1980-08-31T23:59:59.000Z

87

Method for starting and operating an advanced regenerative parallel compound dual fluid heat engine-advanced Cheng cycle(ACC)  

SciTech Connect

In a Cheng cycle, dual fluid heat engine of the type is described having: (i) a gas turbine engine including a compressor for compressing a first working fluid, having a compressor outlet, a combustion chamber in fluid communication with the compressor outlet, a turbine unit having an inlet in fluid communication with the combustion chamber for performing work by expansion of working fluid, and a turbine exhaust; (ii) a heat recovery steam generator coupled to the turbine exhaust for heating a second working fluid having a superheater with an outlet and an inlet, an evaporator having an outlet coupled to the superheater inlet and an evaporator inlet, a heat recovery boiler between the evaporator inlet and outlet having a drum; (iii) an injector for introducing heated second working fluid from the heat recovery steam generator into the gas turbine; (iv) a coolant inlet port for introducing coolant to at least one of turbine nozzles and blades in the gas turbine; and (v) control valve means for selectively throttling flow rate of second working fluid into the gas turbine connected upstream of the injector; (vi) a compressed gas source and pressure regulator selectively in communication with the drum; (vii) a sensor system coupled to gas turbine engine and the heat recovery steam generator for temperature and pressure detection; and (viii) a control system for operating fuel flow to the gas turbine; a method of operation of the heat engine comprising: (a) initializing start conditions in the gas turbine engine and the heat recovery steam generator with the control system; (b) setting the control valve means for idle flow condition of the heat engine; (c) pressurizing the drum with the compressed gas source, (d) starting the gas turbine engine from idle to full load; (e) throttling second working fluid flow rate with the control valve means and shutting off the compressed gas source.

Cheng, D.Y.

1993-08-10T23:59:59.000Z

88

Combined cycle electric power plant and a heat recovery steam generator having improved boiler feed pump flow control  

SciTech Connect

A combined cycle electric power plant is described that includes gas and steam turbines and a steam generator for recovering the heat in the exhaust gases exited from the gas turbine and for using the recovered heat to produce and supply steam to the steam turbine. The steam generator includes an economizer tube and a high pressure evaporator tube and a boiler feed pump for directing the heat exchange fluid serially through the aforementioned tubes. A condenser is associated with the steam turbine for converting the spent steam into condensate water to be supplied to a deaerator for removing undesired air and for preliminarily heating the water condensate before being pumped to the economizer tube. Condensate flow through the economizer tube is maintained substantially constant by maintaining the boiler feed pump at a predetermined, substantially constant rate. A bypass conduit is provided to feed back a portion of the flow heated in the economizer tube to the deaerator; the portion being equal to the difference between the constant flow through the economizer tube and the flow to be directed through the high pressure evaporator tube as required by the steam turbine for its present load.

Martz, L.F.; Plotnick, R.J.

1976-06-29T23:59:59.000Z

89

Base-Load and Peak Electricity from a Combined Nuclear Heat and Fossil Combined-Cycle Plant  

SciTech Connect

A combined-cycle power plant is proposed that uses heat from a high-temperature reactor and fossil fuel to meet base-load and peak electrical demands. The high temperature gas turbine produces shaft power to turn an electric generator. The hot exhaust is then fed to a heat recovery steam generator (HRSG) that provides steam to a steam turbine for added electrical power production. A simplified computational model of the thermal power conversion system was developed in order to parametrically investigate two different steady-state operation conditions: base load nuclear heat only from an Advanced High Temperature Reactor (AHTR), and combined nuclear heat with fossil heat to increase the turbine inlet temperature. These two cases bracket the expected range of power levels, where any intermediate power level can result during electrical load following. The computed results indicate that combined nuclear-fossil systems have the potential to offer both low-cost base-load electricity and lower-cost peak power relative to the existing combination of base-load nuclear plants and separate fossil-fired peak-electricity production units. In addition, electric grid stability, reduced greenhouse gases, and operational flexibility can also result with using the conventional technology presented here for the thermal power conversion system coupled with the AHTR. (authors)

Conklin, James C.; Forsberg, Charles W. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831 (United States)

2007-07-01T23:59:59.000Z

90

Base-Load and Peak Electricity from a Combined Nuclear Heat and Fossil Combined-Cycle Plant  

Science Conference Proceedings (OSTI)

A combined-cycle power plant is proposed that uses heat from a high-temperature reactor and fossil fuel to meet base-load and peak electrical demands. The high-temperature gas turbine produces shaft power to turn an electric generator. The hot exhaust is then fed to a heat recovery steam generator (HRSG) that provides steam to a steam turbine for added electrical power production. A simplified computational model of the thermal power conversion system was developed in order to parametrically investigate two different steady-state operation conditions: base load nuclear heat only from an Advanced High Temperature Reactor (AHTR), and combined nuclear heat with fossil heat to increase the turbine inlet temperature. These two cases bracket the expected range of power levels, where any intermediate power level can result during electrical load following. The computed results indicate that combined nuclear-fossil systems have the potential to offer both low-cost base-load electricity and lower-cost peak power relative to the existing combination of base-load nuclear plants and separate fossil-fired peak-electricity production units. In addition, electric grid stability, reduced greenhouse gases, and operational flexibility can also result with using the conventional technology presented here for the thermal power conversion system coupled with the AHTR.

Conklin, Jim [ORNL; Forsberg, Charles W [ORNL

2007-01-01T23:59:59.000Z

91

The Effect of Alternate Defrost Strategies on the Reverse-Cycle Defrost of an Air-Source Heat Pump  

E-Print Network (OSTI)

The effect of alternate defrost strategies on the transient performance of the air-source heat pump during the reverse-cycle defrost was investigated. Tests of a base-case heat pump configuration and defrost strategy were completed to provide a basis for performance evaluations of the alternate defrost strategies. The compressor and indoor coil fan operated continuously in the base-case defrost strategy, and the outdoor coil fan was stopped. Alternate defrost strategies utilized variations in fan and compressor operation during and after the defrost. Pre-starting of the outdoor coil fan prior to termination of the reverse-cycle defrost reduced pressure spikes commonly seen at defrost termination in the base-case defrost strategy. A strategy in which the compressor was stopped and the outdoor coil was allowed to drain of melted frost during the last three minutes of the defrost improved overall cyclic performance. Strategies which involved stopping of the indoor fan during defrost or delaying the start of the outdoor fan following defrost termination had a negative impact on defrost performance. A final strategy involved down-sizing of the heat pump compressor from 3.0 tons (36,000 btu/hr) capacity to 2.5 tons capacity. This alternate configuration had a comparable overall performance with the base-case while having a reduced frequency of required defrost periods.

Schliesing, J. S.

1988-08-01T23:59:59.000Z

92

The Annual Cycle of Meridional Heat Flux in the Atlantic Ocean at 26.5°N  

Science Conference Proceedings (OSTI)

Total meridional heat flux through a zonal oceanic section at 26.5°N in the Atlantic Ocean is computed from hydrographic, direct current and surface wind observations. The oceanic current and temperature fields are decomposed into depth-averaged ...

Robert L. Molinari; Elizabeth Johns; John F. Festa

1990-03-01T23:59:59.000Z

93

Methods to Mitigate the Effect of Increased Cycling and Load Following on Heat Rate  

Science Conference Proceedings (OSTI)

Most of the U.S. coal-fired plants currently in service were designed for baseload operation. Today, however, actual generation conditions dictate that many of these units operate in a continuous transient mode, following generation demand. As such, they often experience large load changes throughout the day that result in a poorer plant heat rate. Reducing the throttle pressure, also known as sliding pressure, reduces throttling losses and is a potential method to reduce the heat rate penalties ...

2012-12-14T23:59:59.000Z

94

Combined Heat and Power: Coal-Fired Air Turbine (CAT)-Cycle Plant  

DOE Green Energy (OSTI)

By combining an integrated system with a gas turbine, coal-fired air turbine cycle technology can produce energy at an efficiency rate of over 40%, with capital and operating costs below those of competing conventional systems. Read this fact sheet to discover the additional benefits of this exciting new technology.

Recca, L.

1999-01-29T23:59:59.000Z

95

Feasibility Study of a Multi-Purpose Computer Program for Optimizing Heat Rates in Power Cycles  

E-Print Network (OSTI)

A study of currently available commercial codes which evaluate the thermal performance of turbine cycles in power plants is presented. The analytical basis, capabilities, and possible applications of these codes are described. A survey of some user utilities has revealed their strengths and limitations. This paper examines some actual cases where the use of existing codes is either inconvenient or not satisfactory, and might produce somewhat inaccurate or incomplete results. A brief outline of a computer program that can overcome some of these weaknesses is given.

Menuchin, Y.; Singh, K. P.; Hirota, N.

1981-01-01T23:59:59.000Z

96

Non-Space Heating Electrical Consumption in Manufactured Homes: Residential Construction Demonstration Project Cycle II : Final Report.  

SciTech Connect

This report summarizes submeter data of the non-space heating electrical energy use in a sample of manufactured homes. These homes were built to Super Good Cents insulation standards in 1988 and 1989 under the auspices of RCDP Cycle 2 of the Bonneville Power Administration. They were designed to incorporate innovations in insulation and manufacturing techniques developed to encourage energy conservation in this important housing type. Domestic water heating (DWH) and other non-space heat energy consumption, however, were not generally affected by RCDP specifications. The purpose of this study is to establish a baseline for energy conservation in these areas and to present a method for estimating total energy saving benefits associated with these end uses. The information used in this summary was drawn from occupant-read submeters and manufacturersupplied specifications of building shell components, appliances and water heaters. Information was also drawn from a field review of ventilation systems and building characteristics. The occupant survey included a census of appliances and occupant behavior in these manufactured homes. A total of 150 manufactured homes were built under this program by eight manufacturers. An additional 35 homes were recruited as a control group. Of the original 185 houses, approximately 150 had some usable submeter data for domestic hot water and 126 had usable submeter data for all other nonheating consumption. These samples were used as the basis for all consumption analysis. The energy use characteristics of these manufactured homes were compared with that of a similar sample of RCDP site-built homes. In general, the manufactured homes were somewhat smaller and had fewer occupants than the site-built homes. The degree to which seasonal variations were present in non-space heat uses was reviewed.

Onisko, Stephen A.; Roos, Carolyn; Baylon, David

1993-06-01T23:59:59.000Z

97

The Anderson Quin Cycle  

SciTech Connect

The objective of this study was to make a more refined evaluation of the Anderson Quin Cycle based on most recent information on the performance of various elements that will be used in the Anderson Quin Cycle. My original estimate of the work plan for evaluating and optimizing the Anderson Quin Cycle called for 7000 man hours of work. Since this grant was limited to 2150 man hours, we could not expect to achieve all the objectives within the allotted period of work. However, the most relevant program objectives have been completed as reported here. The analysis generally confirms the results originally estimated in my paper on the subject. (Ref. 2) Further optimizations should show even higher efficiencies. The Anderson Quin Cycle (US Patent applied for) basically consists of 5 elements in the power cycle: A refrigeration system to cool and clean the inlet air before it enters the compressor that supplies air for the gas turbine; a gas turbine consisting of a compressor, combustor, and turbine; a steam boiler and steam turbine system using the heat from the exhaust gas out of the gas turbine; a vapor turbine cycle, which utilizes the condensed heat from the exhaust of the steam turbine and the exhaust gas heat leaving the steam boiler to operate a vapor turbine cycle which utilizes another fluid than water, in this case isobutane; and the fifth element consists of a gas cooler and heat pump system, which removes the heat from the exhaust gas to lower its temperature essentially to atmospheric temperature, and at the same time permits treatment of the exhaust gas to remove acid components such as sulfur dioxide and nitrogen oxides. Current industry accepted component characteristics were incorporated in the performance analysis of the overall cycle, ensuring accurate and meaningful operating predictions. The characteristics and performance of each of the elements are described. The thermal efficiency of the optimized calculated Anderson Quin Cycle is 62 percent.

Anderson, J.H.; Bilbow, W.M.

1993-03-18T23:59:59.000Z

98

Proceedings: Eighth International Conference on Cycle Chemistry in Fossil and Combined Cycle Plants with Heat Recovery Steam Generators, June 20-22, 2006, Calgary, Alberta Canada  

Science Conference Proceedings (OSTI)

Proper selection, application, and optimization of the cycle chemistry have long been recognized as integral to ensuring the highest possible levels of component availability and reliability in fossil-fired generating plant units. These proceedings of the Eighth EPRI International Conference on Cycle Chemistry in Fossil Plants address state-of-the-art practices in conventional and combined cycle plants. The content provides a worldwide perspective on cycle chemistry practices, and insight as to industry ...

2007-03-20T23:59:59.000Z

99

A New Absorption Cycle: The Single-Effect Regenerative Absoprtion Refrigeration Cycle  

E-Print Network (OSTI)

REGENERATIVE ABSORPTION REFRIGERATION CYCLE ABSTRACT A new absorption cycle , using heat as the energy

Dao, K.

2011-01-01T23:59:59.000Z

100

Final Report: Modifications and Optimization of the Organic Rankine Cycle to Improve the Recovery of Waste Heat  

Science Conference Proceedings (OSTI)

This research and development (R&D) project exemplifies a shared public private commitment to advance the development of energy efficient industrial technologies that will reduce the U.S. dependence upon foreign oil, provide energy savings and reduce greenhouse gas emissions. The purpose of this project was to develop and demonstrate a Direct Evaporator for the Organic Rankine Cycle (ORC) for the conversion of waste heat from gas turbine exhaust to electricity. In conventional ORCs, the heat from the exhaust stream is transferred indirectly to a hydrocarbon based working fluid by means of an intermediate thermal oil loop. The Direct Evaporator accomplishes preheating, evaporation and superheating of the working fluid by a heat exchanger placed within the exhaust gas stream. Direct Evaporation is simpler and up to 15% less expensive than conventional ORCs, since the secondary oil loop and associated equipment can be eliminated. However, in the past, Direct Evaporation has been avoided due to technical challenges imposed by decomposition and flammability of the working fluid. The purpose of this project was to retire key risks and overcome the technical barriers to implementing an ORC with Direct Evaporation. R&D was conducted through a partnership between the Idaho National Laboratory (INL) and General Electric (GE) Global Research Center (GRC). The project consisted of four research tasks: (1) Detailed Design & Modeling of the ORC Direct Evaporator, (2) Design and Construction of Partial Prototype Direct Evaporator Test Facility, (3) Working Fluid Decomposition Chemical Analyses, and (4) Prototype Evaluation. Issues pertinent to the selection of an ORC working fluid, along with thermodynamic and design considerations of the direct evaporator, were identified. The FMEA (Failure modes and effects analysis) and HAZOP (Hazards and operability analysis) safety studies performed to mitigate risks are described, followed by a discussion of the flammability analysis of the direct evaporator. A testbed was constructed and the prototype demonstrated at the GE GRC Niskayuna facility.

Donna Post Guillen; Jalal Zia

2013-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

The evaluation of a solar-driven aqua-ammonia diffusion absorption heating and cooling cycle / M.C. Potgieter.  

E-Print Network (OSTI)

??Several steps are followed in order to evaluate the cycle as the title suggests. The diffusion absorption refrigerator (DAR) cycle performance is evaluated when using… (more)

Potgieter, Marthinus Christiaan

2013-01-01T23:59:59.000Z

102

Annual Cycle of Poleward Heat Transport in the Ocean: Results from High-Resolution Modeling of the North and Equatorial Atlantic  

Science Conference Proceedings (OSTI)

The annual cycle of meridional heat transport in the North and equatorial Atlantic Ocean is studied by means of the high-resolution numerical model that had been developed in recent years as a Community Modeling Effort for the World Ocean ...

Claus W. Böning; Peter Herrmann

1994-01-01T23:59:59.000Z

103

Advanced heat pump for the recovery of volatile organic compounds. Phase 1, Conceptual design of an advanced Brayton cycle heat pump for the recovery of volatile organic compounds: Final report  

Science Conference Proceedings (OSTI)

Emissions of Volatile Organic Compounds (VOC) from stationary industrial and commercial sources represent a substantial portion of the total US VOC emissions. The ``Toxic-Release Inventory`` of The US Environmental Protection Agency estimates this to be at about 3 billion pounds per year (1987 estimates). The majority of these VOC emissions are from coating processes, cleaning processes, polymer production, fuel production and distribution, foam blowing,refrigerant production, and wood products production. The US Department of Energy`s (DOE) interest in the recovery of VOC stems from the energy embodied in the recovered solvents and the energy required to dispose of them in an environmentally acceptable manner. This Phase I report documents 3M`s work in close working relationship with its subcontractor Nuclear Consulting Services (Nucon) for the preliminary conceptual design of an advanced Brayton cycle heat pump for the recovery of VOC. Nucon designed Brayton cycle heat pump for the recovery of methyl ethyl ketone and toluene from coating operations at 3M Weatherford, OK, was used as a base line for the work under cooperative agreement between 3M and ODE. See appendix A and reference (4) by Kovach of Nucon. This cooperative agreement report evaluates and compares an advanced Brayton cycle heat pump for solvent recovery with other competing technologies for solvent recovery and reuse. This advanced Brayton cycle heat pump is simple (very few components), highly reliable (off the shelf components), energy efficient and economically priced.

Not Available

1992-03-01T23:59:59.000Z

104

Heat transfer research in General Electric, 1910-1960; Examples of the product-driven innovation cycle  

SciTech Connect

General Electric has a long and varied history of doing research on heat transfer, and using the results in its products and processes. Lessons it has learned during the half-century from 1910 to 1950 suggest a need for revision in the standard models used by economists to describe the way industry generates new technology and uses it to achieve innovations. The generation of new technology or the better use of old technology begins, not with a demand from the marketplace or a push from research, but from consideration of an already existing product. Problems or opportunities involving that product drive engineers or scientists to search for new knowledge. That knowledge proves useful in the development of a product, perhaps the one that initiated the search for knowledge, or perhaps a very different one. The important point is that however esoteric or mundane is the research in the middle of the cycle, the beginning and end are always products (or the processes used to make products), not scientists' ideas or customers demands.

Wise, G. (General Electric R and D Center, Schenectady, NY (US))

1991-01-01T23:59:59.000Z

105

Investigations of supercritical CO2 Rankine cycles for geothermal power plants  

Science Conference Proceedings (OSTI)

Supercritical CO2 Rankine cycles are investigated for geothermal power plants. The system of equations that describe the thermodynamic cycle is solved using a Newton-Rhapson method. This approach allows a high computational efficiency of the model when thermophysical properties of the working fluid depend strongly on the temperature and pressure. Numerical simulation results are presented for different cycle configurations in order to assess the influences of heat source temperature, waste heat rejection temperatures and internal heat exchanger design on cycle efficiency. The results show that thermodynamic cycle efficiencies above 10% can be attained with the supercritical brayton cycle while lower efficiencies can be attained with the transcritical CO2 Rankine cycle.

Sabau, Adrian S [ORNL; Yin, Hebi [ORNL; Qualls, A L [ORNL; McFarlane, Joanna [ORNL

2011-01-01T23:59:59.000Z

106

Investigating potential efficiency improvement for light-duty transportation applications through simulation of an organic Rankine cycle for waste-heat recovery  

SciTech Connect

Modern diesel engines used in light-duty transportation applications have peak brake thermal efficiencies in the range of 40-42% for high-load operation with substantially lower efficiencies at realistic road-load conditions. Thermodynamic energy and exergy analysis reveals that the largest losses from these engines are due to heat loss and combustion irreversibility. Substantial improvement in overall engine efficiency requires reducing or recovering these losses. Unfortunately, much of the heat transfer either occurs at relatively low temperatures resulting in large entropy generation (such as in the air-charge cooler), is transferred to low-exergy flow streams (such as the oil and engine coolant), or is radiated or convected directly to the environment. While there are significant opportunities for recovery from the exhaust and EGR cooler for heavy-duty applications, the potential benefits of such a strategy for light-duty applications are unknown due to transient operation, low-load operation at typical driving conditions, and the added mass of the system. We have developed an organic Rankine cycle model using GT-Suite to investigate the potential for efficiency improvement through waste-heat recovery from the exhaust and EGR cooler of a light-duty diesel engine. Results from steady-state and drive-cycle simulations are presented, and we discuss strategies to address operational difficulties associated with transient drive cycles and competition between waste-heat recovery systems, turbochargers, aftertreatment devices, and other systems for the limited thermal resources.

Edwards, Kevin Dean [ORNL; Wagner, Robert M [ORNL

2010-01-01T23:59:59.000Z

107

The Seasonal Cycle of Meridional Heat Transport in a Numerical Model of the Pacific Equatorial Upwelling Zone  

Science Conference Proceedings (OSTI)

The seasonal heat transport mechanisms important in the Pacific equatorial upwelling zone are investigated using the primitive equation, reduced gravity model developed by Gent and Cane. Mechanisms of meridional heat transport are shown and ...

Esther C. Brady; Peter R. Gent

1994-12-01T23:59:59.000Z

108

Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger  

DOE Patents (OSTI)

A magnetohydrodynamic (MHD) power generating system in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.

Berry, Gregory F. (Naperville, IL); Minkov, Vladimir (Skokie, IL); Petrick, Michael (Joliet, IL)

1988-01-01T23:59:59.000Z

109

Results of heat tests of the TGE-435 main boiler in the PGU-190/220 combined-cycle plant of the Tyumen' TETs-2 cogeneration plant  

Science Conference Proceedings (OSTI)

Special features of operation of a boiler operating as a combined-cycle plant and having its own furnace and burner unit are descried. The flow of flue gases on the boiler is increased due to feeding of exhaust gases of the GTU into the furnace, which intensifies the convective heat exchange. In addition, it is not necessary to preheat air in the convective heating surfaces (the boiler has no air preheater). The convective heating surfaces of the boiler are used for heating the feed water, thus replacing the regeneration extractions of the steam turbine (HPP are absent in the circuit) and partially replacing the preheating of condensate (the LPP in the circuit of the unit are combined with preheaters of delivery water). Regeneration of the steam turbine is primarily used for the district cogeneration heating purposes. The furnace and burner unit of the exhaust-heat boiler (which is a new engineering solution for the given project) ensures utilization of not only the heat of the exhaust gases of the GTU but also of their excess volume, because the latter contains up to 15% oxygen that oxidizes the combustion process in the boiler. Thus, the gas temperature at the inlet to the boiler amounts to 580{sup o}C at an excess air factor a = 3.50; at the outlet these parameters are utilized to T{sub out} = 139{sup o}C and a{sub out} = 1.17. The proportions of the GTU/boiler loads that can actually be organized at the generating unit (and have been checked by testing) are presented and the proportions of loads recommended for the most efficient operation of the boiler are determined. The performance characteristics of the boiler are presented for various proportions of GTU/boiler loads. The operating conditions of the superheater and of the convective trailing heating surfaces are presented as well as the ecological parameters of the generating unit.

A.V. Kurochkin; A.L. Kovalenko; V.G. Kozlov; A.I. Krivobok [Engineering Center of the Ural Power Industry (Russian Federation)

2007-01-15T23:59:59.000Z

110

Combined cycle electric power plant and heat recovery steam generator having improved multi-loop temperature control of the steam generated  

SciTech Connect

A combined cycle electric power plant is described that includes gas and steam turbines and a steam generator for recovering the heat in the exhaust gases exited from the gas turbine and for using the recovered heat to produce and supply steam to the steam turbine. The steam generator includes a superheater tube and a steam drum from which heated steam is directed through the superheater to be additionally heated into superheated steam by the exhaust gas turbine gases. An afterburner serves to further heat the exhaust gas turbine gases passed to the superheater tube and a bypass conduit is disposed about the superheater tube whereby a variable steam flow determined by a bypass valve disposed in the bypass conduit may be directed about the superheater tube to be mixed with the superheated steam therefrom, whereby the temperature of the superheated steam supplied to the steam turbine may be accurately controlled. Steam temperature control means includes a first control loop responsive to the superheated steam temperature for regulating the position of the bypass valve with respect to a first setpoint, and a second control loop responsive to the superheated steam temperature for controlling the fuel supply to the afterburner with respect to a second setpoint varying in accordance with the bypass valve position. In particular, as the bypass valve position increases, the second setpoint, originally higher, is lowered toward a value substantially equal to that of the first setpoint.

Martz, L.F.; Plotnick, R.J.

1976-08-17T23:59:59.000Z

111

Milestone Report #2: Direct Evaporator Leak and Flammability Analysis Modifications and Optimization of the Organic Rankine Cycle to Improve the Recovery of Waste Heat  

Science Conference Proceedings (OSTI)

The direct evaporator is a simplified heat exchange system for an Organic Rankine Cycle (ORC) that generates electricity from a gas turbine exhaust stream. Typically, the heat of the exhaust stream is transferred indirectly to the ORC by means of an intermediate thermal oil loop. In this project, the goal is to design a direct evaporator where the working fluid is evaporated in the exhaust gas heat exchanger. By eliminating one of the heat exchangers and the intermediate oil loop, the overall ORC system cost can be reduced by approximately 15%. However, placing a heat exchanger operating with a flammable hydrocarbon working fluid directly in the hot exhaust gas stream presents potential safety risks. The purpose of the analyses presented in this report is to assess the flammability of the selected working fluid in the hot exhaust gas stream stemming from a potential leak in the evaporator. Ignition delay time for cyclopentane at temperatures and pressure corresponding to direct evaporator operation was obtained for several equivalence ratios. Results of a computational fluid dynamic analysis of a pinhole leak scenario are given.

Donna Post Guillen

2013-09-01T23:59:59.000Z

112

A Comparison of Supercritical Carbon Dioxide Power Cycle Configurations with an Emphasis on CSP Applications (Presentation)  

SciTech Connect

Recent research suggests that an emerging power cycle technology using supercritical carbon dioxide (s-CO2) operated in a closed-loop Brayton cycle offers the potential of equivalent or higher cycle efficiency versus supercritical or superheated steam cycles at temperatures relevant for CSP applications. Preliminary design-point modeling suggests that s-CO2 cycle configurations can be devised that have similar overall efficiency but different temperature and/or pressure characteristics. This paper employs a more detailed heat exchanger model than previous work to compare the recompression and partial cooling cycles, two cycles with high design-point efficiencies, and illustrates the potential advantages of the latter. Integration of the cycles into CSP systems is studied, with a focus on sensible heat thermal storage and direct s-CO2 receivers. Results show the partial cooling cycle may offer a larger temperature difference across the primary heat exchanger, thereby potentially reducing heat exchanger cost and improving CSP receiver efficiency.

Neises, T.; Turchi, C.

2013-09-01T23:59:59.000Z

113

Approximation of Ocean Heat Storage by Ocean–Atmosphere Energy Exchange: Implications for Seasonal Cycle Mixed Layer Ocean Formulations  

Science Conference Proceedings (OSTI)

The approximation of ocean heat storage by the net surface energy flux and the implications for zonal mean SST simulation using mixed layer ocean formulation are examined. The analysis considers both constant and variable depth mixed layers. ...

Robert G. Gallimore; David D. Houghton

1987-08-01T23:59:59.000Z

114

A Composite Life Cycle of Nonsquall Mesoscale Convective Systems over the Tropical Ocean. Part II: Heat and Moisture Budgets  

Science Conference Proceedings (OSTI)

The heat and moisture budgets associated with five large nonsquall cloud clusters observed during Phase 3 of the Global Atmospheric Research Program's Atlantic Tropical Experiment (GATE) are investigated. The input data for the budget ...

Steven K. Esbensen; Jough-Tai Wang; Edward I. Tollerud

1988-02-01T23:59:59.000Z

115

Design study of a two-phase turbine bottoming cycle. Final report. [Therminol 66 heated in diesel exhaust  

SciTech Connect

The use of a biphase turbine system to recover waste heat from diesel engines was examined and found to have many favorable attributes. Among these were low rpm, high torque, low heat exchanger cost, and simplicity. Several candidate working fluid combinations were tested at temperatures of interest. The contact heat exchanger concept was substantiated by large scale experiment. The program includes subscale tests of key hardware components of a biphase turbine bottoming system. These are the two-phase nozzle, two-phase turbine, and direct contact heat exchanger. A comprehensive cost analysis was completed. A three-year program leading to a full-size system field demonstration has been planned. Progress in the first year of this program and the effort started on the second year program are reported.

Studhalter, W R

1979-06-15T23:59:59.000Z

116

Development of the dual-cycle absorption heat pump for residential application. Appendix B: Analysis of materials compatibility and corrosion for dual-cycle absorption heat pump. Final report, April 1984-March 1990  

SciTech Connect

Engineering alloys were analyzed in an effort to identify corrosion resistant materials for the absorption heat pump (AHP). Testing focused on the corrosion behavior of carbon steels and austentic stainless steels Types 304 and 316L. Most of the tests were conducted in lithium bromide solutions at various temperatures under non-flowing or static conditions. Failures due to corrosion in prototype AHP units were investigated as they occurred. A literature review was performed on the corrosion behavior of materials in lithium bromide, ammonia water, and calcium chloride environments. Material recommendations and heat treating procedures are discussed.

Not Available

1990-04-01T23:59:59.000Z

117

Evaluation of an Absorption Heat Pump to Mitigate Plant Capacity Reduction Due to Ambient Temperature Rise for an Air-Cooled Ammonia and Water Cycle: Preprint  

DOE Green Energy (OSTI)

Air-cooled geothermal plants suffer substantial decreases in generating capacity at increased ambient temperatures. As the ambient temperature rises by 50 F above a design value of 50 F, at low brine-resource temperatures, the decrease in generating capacity can be more than 50%. This decrease is caused primarily by increased condenser pressure. Using mixed-working fluids has recently drawn considerable attention for use in power cycles. Such cycles are more readily amenable to use of absorption ''heat pumps.'' For a system that uses ammonia and water as the mixed-working fluid, this paper evaluates using an absorption heat pump to reduce condenser backpressure. At high ambient temperatures, part of the turbine exhaust vapor is absorbed into a circulating mixed stream in an absorber in series with the main condenser. This steam is pumped up to a higher pressure and heated to strip the excess vapor, which is recondensed using an additional air-cooled condenser. The operating conditions are chosen to reconstitute this condensate back to the same concentration as drawn from the original system. We analyzed two power plants of nominal 1-megawatt capacity. The design resource temperatures were 250 F and 300 F. Ambient temperature was allowed to rise from a design value of 50 F to 100 F. The analyses indicate that using an absorption heat pump is feasible. For the 300 F resource, an increased brine flow of 30% resulted in a net power increase of 21%. For the 250 F resource, the increase was smaller. However, these results are highly plant- and equipment-specific because evaluations must be carried out at off-design conditions for the condenser. Such studies should be carried out for specific power plants that suffer most from increased ambient temperatures.

Bharathan, D.; Nix, G.

2001-08-06T23:59:59.000Z

118

Design of a novel conduction heating based stress-thermal cycling apparatus for composite materials and its utilization to characterize composite microcrack damage thresholds  

E-Print Network (OSTI)

The objective of this research was to determine the effect of thermal cycling combined with mechanical loading on the development of microcracks in M40J/PMR-II- 50, the second generation aerospace application material. The objective was pursued by finding the critical controlling parameters for microcrack formation from mechanical stress-thermal cycling test. Three different in-plane strains (0%, 0.175~0.350%, and 0.325~0.650%) were applied to the composites by clamping composite specimens (M40J/PMR-II-50, [0,90]s, a unitape cross-ply) on the radial sides of half cylinders having two different radii (78.74mm and 37.96mm). Three different thermal loading experiments, 1) 23oC to �196oC to 250oC, 2) 23oC to 250oC, and 3) 23oC to -196oC, were performed as a function of mechanical inplane strain levels, heating rates, and number of thermal cycles. The apparatus generated cracks related to the in-plane stresses (or strains) on plies. The design and analysis concept of the synergistic stress-thermal cycling experiment was simplified to obtain main and interaction factors by applying 2k factorial design from the various factors affecting microcrack density of M40J/PMR-II-50. Observations indicate that the higher temperature portion of the cycle under load causes fiber/matrix interface failure. Subsequent exposure to higher stresses in the cryogenic temperature region results in composite matrix microcracking due to the additional stresses associated with the fiber-matrix thermal expansion mismatch.

Ju, Jaehyung

2005-08-01T23:59:59.000Z

119

Theoretical thermodynamic analysis of a closed-cycle process for the conversion of heat into electrical energy  

E-Print Network (OSTI)

into electrical energy by means of a distiller and an electrochemical cell. A. Caratia , M. Marinoa , D. Brogiolib) Abstract We analyse a device aimed at the conversion of heat into electrical energy, based on a closed with different concentrations can be tapped and converted into electrical energy, e.g. by means

Carati, Andrea

120

NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger  

DOE Green Energy (OSTI)

One key long-standing issue that must be overcome to fully realize the successful growth of nuclear power is to determine other benefits of nuclear energy apart from meeting the electricity demands. The Next Generation Nuclear Plant (NGNP) will most likely be producing electricity and heat for the production of hydrogen and/or oil retrieval from oil sands and oil shale to help in our national pursuit of energy independence. For nuclear process heat to be utilized, intermediate heat exchange is required to transfer heat from the NGNP to the hydrogen plant or oil recovery field in the most efficient way possible. Development of nuclear reactor - process heat technology has intensified the interest in liquid metals as heat transfer media because of their ideal transport properties. Liquid metal heat exchangers are not new in practical applications. An important rational for considering liquid metals is the potential convective heat transfer is among the highest known. Thus explains the interest in liquid metals as coolant for intermediate heat exchange from NGNP. For process heat it is desired that, intermediate heat exchangers (IHX) transfer heat from the NGNP in the most efficient way possible. The production of electric power at higher efficiency via the Brayton Cycle, and hydrogen production, requires both heat at higher temperatures and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. Compact heat exchangers maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. High temperature IHX design requirements are governed in part by the allowable temperature drop between the outlet and inlet of the NGNP. In order to improve the characteristics of heat transfer, liquid metal phase change heat exchangers may be more effective and efficient. This paper explores the overall heat transfer characteristics and pressure drop of the phase change heat exchanger with Na as the heat exchanger coolant. In order to design a very efficient and effective heat exchanger one must optimize the design such that we have a high heat transfer and a lower pressure drop, but there is always a trade-off between them. Based on NGNP operational parameters, a heat exchanger analysis with the sodium phase change will be presented to show that the heat exchanger has the potential for highly effective heat transfer, within a small volume at reasonable cost.

Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

2008-09-01T23:59:59.000Z

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121

Heat Recovery Steam Generator (HRSG) Chemical Cleaning Guidelines  

Science Conference Proceedings (OSTI)

Combined cycle units with heat recovery steam generators (HRSGs) represent a substantial fraction of the new fossil generating capacity installed around the world since the 1990s. One of the goals of the EPRI HRSG Dependability Program is to make availability losses due to tube failures very low, no more than one per year. An earlier guideline, "Interim Cycle Chemistry Guidelines for Combined Cycle Heat Recovery Steam Generators" (EPRI Report TR-110051), shows organizations how to set up chemistry progra...

2003-12-03T23:59:59.000Z

122

The Anderson Quin Cycle. Final report  

SciTech Connect

The objective of this study was to make a more refined evaluation of the Anderson Quin Cycle based on most recent information on the performance of various elements that will be used in the Anderson Quin Cycle. My original estimate of the work plan for evaluating and optimizing the Anderson Quin Cycle called for 7000 man hours of work. Since this grant was limited to 2150 man hours, we could not expect to achieve all the objectives within the allotted period of work. However, the most relevant program objectives have been completed as reported here. The analysis generally confirms the results originally estimated in my paper on the subject. (Ref. 2) Further optimizations should show even higher efficiencies. The Anderson Quin Cycle (US Patent applied for) basically consists of 5 elements in the power cycle: A refrigeration system to cool and clean the inlet air before it enters the compressor that supplies air for the gas turbine; a gas turbine consisting of a compressor, combustor, and turbine; a steam boiler and steam turbine system using the heat from the exhaust gas out of the gas turbine; a vapor turbine cycle, which utilizes the condensed heat from the exhaust of the steam turbine and the exhaust gas heat leaving the steam boiler to operate a vapor turbine cycle which utilizes another fluid than water, in this case isobutane; and the fifth element consists of a gas cooler and heat pump system, which removes the heat from the exhaust gas to lower its temperature essentially to atmospheric temperature, and at the same time permits treatment of the exhaust gas to remove acid components such as sulfur dioxide and nitrogen oxides. Current industry accepted component characteristics were incorporated in the performance analysis of the overall cycle, ensuring accurate and meaningful operating predictions. The characteristics and performance of each of the elements are described. The thermal efficiency of the optimized calculated Anderson Quin Cycle is 62 percent.

Anderson, J.H.; Bilbow, W.M.

1993-03-18T23:59:59.000Z

123

Thermal and hydraulic performance tests of a sieve-tray direct-contact heat exchanger vaporizing pure and mixed-hydrocarbon Rankine-cycle working fluids  

DOE Green Energy (OSTI)

Experiments investigating a sieve-tray direct-contact heat exchanger were conducted at the Raft River Geothermal Test Site in southeastern Idaho using the 60-kW Mobile Heat Cycle Research Facility operating in the thermal loop mode (without a turbine). Isobutane, propane, and several hydrocarbon mixtures were heated and boiled in the direct-contact column, which is approx. 12 in. in diameter and 19-1/2 ft. high, using the energy from a 280/sup 0/F geothermal resource. Using pure fluids, isobutane or propane, the column operated much as intended, with 17 trays used for preheating and one or two accomplishing the boiling. For the pure fluids, individual tray efficiencies were found to be 70% or higher for preheating, and close to 100% for boiling; column pinch points were projected to be well under 1/sup 0/F with some runs reaching values as low as approx. 0.02/sup 0/F. Maximum geofluid throughputs for the isobutane tests corresponded roughly to the terminal rise velocity of a 1/32 in. working fluid droplet in geofluid. Boiling was found to occur in as many as 12 trays for the mixtures having the highest concentrations of the minor component, with overall efficiencies in the boiling section estimated on the order of 25 or 30%. Preheating tray efficiencies appeared to be fairly independent of working fluid, with pinch points ranging from as low as approx. 0.03/sup 0/F for a 0.95 isobutane/0.05 hexane mixture to approx. 2.3/sup 0/F for a 0.85 isobutane/0.05 hexane mixture. Column operation was noticeably less stable for the mixtures than for the pure fluids, with maximum throughputs dropping to as low as 40 to 50% of those for the pure fluids.

Mines, G.L.; Demuth, O.J.; Wiggins, D.J.

1983-08-01T23:59:59.000Z

124

Analysis of Energy, Environmental and Life Cycle Cost Reduction Potential of Ground Source Heat Pump (GSHP) in Hot and Humid Climate  

DOE Green Energy (OSTI)

It has been widely recognized that the energy saving benefits of GSHP systems are best realized in the northern and central regions where heating needs are dominant or both heating and cooling loads are comparable. For hot and humid climate such as in the states of FL, LA, TX, southern AL, MS, GA, NC and SC, buildings have much larger cooling needs than heating needs. The Hybrid GSHP (HGSHP) systems therefore have been developed and installed in some locations of those states, which use additional heat sinks (such as cooling tower, domestic water heating systems) to reject excess heat. Despite the development of HGSHP the comprehensive analysis of their benefits and barriers for wide application has been limited and often yields non-conclusive results. In general, GSHP/HGSHP systems often have higher initial costs than conventional systems making short-term economics unattractive. Addressing these technical and financial barriers call for additional evaluation of innovative utility programs, incentives and delivery approaches. From scientific and technical point of view, the potential for wide applications of GSHP especially HGSHP in hot and humid climate is significant, especially towards building zero energy homes where the combined energy efficient GSHP and abundant solar energy production in hot climate can be an optimal solution. To address these challenges, this report presents gathering and analyzing data on the costs and benefits of GSHP/HGSHP systems utilized in southern states using a representative sample of building applications. The report outlines the detailed analysis to conclude that the application of GSHP in Florida (and hot and humid climate in general) shows a good potential.

Yong X. Tao; Yimin Zhu

2012-04-26T23:59:59.000Z

125

Novel Power Cycle for Combined-Cycle Systems and Utility Power Plants  

E-Print Network (OSTI)

The description of a new power cycle, based on the use of a multicomponent working fluid, was published earlier. A thermodynamic analysis of this cycle has demonstrated its superiority over the currently used Rankine Cycle, and a distribution of losses in the subsystems of this cycle has been established. A new, improved variant of the cycle, which provides 10% efficiency improvement over the initial variant, has been developed. The new variant employs a cooling of the working fluid between turbine stages and a recuperation of the released heat for supplementation of the boiler heat supply. Analysis shows that with this new, improved cycle efficiencies of up to 52% for a combined-cycle system employing standard turbines, and of up to 55% when modern high-temperature gas turbines are employed, can be achieved. The same cycle can be utilized to retrofit existing direct-fired power plants, providing an efficiency of up to 42%. The possible implications off such a cycle implementation are briefly discussed. The Electric Power Research Institute (EPRI) is now conducting a study of this cycle.

Kalina, A. L.

1986-06-01T23:59:59.000Z

126

Process design of the LASL Bismuth Sulfate thermochemical hydrogen cycle  

SciTech Connect

A new process engineering flowsheet reflecting an improved design of the LASL Bismuth Sulfate thermochemical cycle is presented. The design is based on laboratory data that indicate a lowered endothermic heat load for a partial decomposition of the solid bismuth sulfate. A small electrical energy demand should result from operation of the sulfur dioxide electrolytic step at lower acid concentration, in principle. The results of the flowsheeting analysis yield a thermal efficiency of 50% for the cycle when coupled to a conceptual fusion energy heat source at 1500/sup 0/K. A parametric analysis shows a slight drop in efficiency as the temperature of the heat source is decreased. The LASL Bismuth Sulfate thermochemical cycle appears to have potential as a means of producing hydrogen from high-temperature heat sources such as fusion, fission, and solar energy; it also appears to be competitive with alternative thermochemical cycles as well as with water electrolysis for hydrogen production.

Cox, K.E.; Pendergrass, J.H.; Jones, W.M.

1979-01-01T23:59:59.000Z

127

" "," ",,," Steam Turbines Supplied by Either Conventional or Fluidized Bed Boilers",,,"Conventional Combusion Turbines with Heat Recovery",,,"Combined-Cycle Combusion Turbines",,,"Internal Combusion Engines with Heat Recovery",,," Steam Turbines Supplied by Heat Recovered from High-Temperature Processes",,,," "  

U.S. Energy Information Administration (EIA) Indexed Site

3 Relative Standard Errors for Table 8.3;" 3 Relative Standard Errors for Table 8.3;" " Unit: Percents." " "," ",,," Steam Turbines Supplied by Either Conventional or Fluidized Bed Boilers",,,"Conventional Combusion Turbines with Heat Recovery",,,"Combined-Cycle Combusion Turbines",,,"Internal Combusion Engines with Heat Recovery",,," Steam Turbines Supplied by Heat Recovered from High-Temperature Processes",,,," " " "," " ," " "NAICS Code(a)","Subsector and Industry","Establishments(b)","Establishments with Any Cogeneration Technology in Use(c)","In Use(d)","Not in Use","Don't Know","In Use(d)","Not in Use","Don't Know","In Use(d)","Not in Use","Don't Know","In Use(d)","Not in Use","Don't Know","In Use(d)","Not in Use","Don't Know"

128

Heat pump system  

DOE Patents (OSTI)

An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

Swenson, Paul F. (Cleveland, OH); Moore, Paul B. (Fedhaurn, FL)

1982-01-01T23:59:59.000Z

129

Heat pump system  

DOE Patents (OSTI)

An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchangers and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

Swenson, Paul F. (Cleveland, OH); Moore, Paul B. (Fedhaurn, FL)

1979-01-01T23:59:59.000Z

130

Crude Oil Price Cycles  

Gasoline and Diesel Fuel Update (EIA)

The heating oil and diesel fuel price runups in late January were made even more problematic by coming on top of the high side of the latest crude market cycle. Over the past 10...

131

Crude Oil Price Cycles  

U.S. Energy Information Administration (EIA)

The heating oil and diesel price runups in late January were made even more problematic by coming on top of the high side of the latest crude market cycle.

132

Willamina Project Report : Indirect-Fired, Biomass-Fueled, Combined-Cycle, Gas Turbine Power Plant Using a Ceramic Heat Exchanger. Volume 1. Conceptual Plant Design and Analysis. Final report. [Contains Glossary  

SciTech Connect

A new technology for a wood-fueled electrical generation plant was evaluated. The proposed plant utilizes an indirectly fired gas turbine (IFGT) using a ceramic heat exchanger for high efficiency, due to its high temperature capability. The proposed plant utilizes a wood-fueled furnace with a ceramic heat exchanger to heat compressed air for a gas turbine. The configuration proposed is a combined cycle power plant that can produce 6 to 12 MW, depending upon the amount of wood used to supplementally fire a heat recovery steam generator (HRSG), which in turn powers a steam turbine. Drawings, specifications, and cost estimates based on a combined cycle analysis and wood-fired HRSG were developed. The total plant capital cost was estimated to be $13.1 million ($1640/kW). The heat rate for a 8-MW plant was calculated to be 10,965 Btu/kW when using wood residues with a 42% moisture content. Levelized electric energy costs were estimated to be 6.9 cents/kWh.

F.W. Braun Engineers.

1984-05-01T23:59:59.000Z

133

Test and evaluation of a solar-powered laboratory turbocompressor system for building heating and cooling. Final technical report. [Rankine cycle  

SciTech Connect

Extensive testing of an available laboratory Rankine-cycle turbocompressor cooling system was conducted over a range of temperatures consistent with present-day flat-plate and advanced medium-concentration solar collectors and at air- and water-cooled condenser temperature levels. Over 700 hours of testing demonstrated the high performance potential of such systems over a wide range of operational conditions and has provided design guidelines and preliminary specifications for future systems. Minor modifications were made to the laboratory system. These modifications included: (1) demonstration of three tons of cooling at a turbine inlet temperature of about 160 F, (2) efficient operation (i.e., COP of approximately 0.45) at turbine inlet temperatures of 240 F at air-cooled condenser temperatures, and (3) a COP in excess of 0.5 and more than five tons of cooling at system turbine inlet temperature levels of 200 F with water-cooled condenser temperatures. Generally, the test data correlated very well with detailed analytical design and off-design performance projections over the range of operating conditions. These data correlations indicate that the achieved performance levels were limited by mismatching of the existing turbomachinery elements. Data and experience obtained in this program substantiate the judgment that incorporating well-matched turbomachinery, based on existing technology, would result in the achievement of the full potential of a turbocompressor system for both air- and water-cooled operation. Prototype turbocompressor systems can be designed and developed which demonstrate high performance, (i.e., a COP approaching 1.0 and 0.75 for water and air-cooled operation, respectively), versatile operational features, permitting use of different collectors with a range of temperature capability, and potential for significant energy savings when used as solar-powered heating and cooling systems.

Biancardi, F.R.; Meader, M.D. Melikian, G.; Landerman, A.M.; Hall, J.B.

1977-03-01T23:59:59.000Z

134

Variable pressure power cycle and control system  

DOE Patents (OSTI)

A variable pressure power cycle and control system that is adjustable to a variable heat source is disclosed. The power cycle adjusts itself to the heat source so that a minimal temperature difference is maintained between the heat source fluid and the power cycle working fluid, thereby substantially matching the thermodynamic envelope of the power cycle to the thermodynamic envelope of the heat source. Adjustments are made by sensing the inlet temperature of the heat source fluid and then setting a superheated vapor temperature and pressure to achieve a minimum temperature difference between the heat source fluid and the working fluid.

Goldsberry, Fred L. (Spring, TX)

1984-11-27T23:59:59.000Z

135

Air-Source Heat Pump Basics | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Air-Source Heat Pump Basics Air-Source Heat Pump Basics Air-Source Heat Pump Basics August 19, 2013 - 11:03am Addthis Air-source heat pumps transfer heat between the inside of a building and the outside air. How Air-Source Heat Pumps Work This diagram of a split-system heat pump heating cycle shows refrigerant circulating through a closed loop that passes through the wall of a house. Inside the house the refrigerant winds through indoor coils, with a fan blowing across them, and outside the house is another fan and another set of coils, the outdoor coils. A compressor is between the coils on one half of the loop, and an expansion valve is between the coils on the other half. The diagram is explained in the caption. In heating mode, an air-source heat pump evaporates a refrigerant in the outdoor coil; as the liquid evaporates it pulls

136

Air-Source Heat Pump Basics | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Source Heat Pump Basics Source Heat Pump Basics Air-Source Heat Pump Basics August 19, 2013 - 11:03am Addthis Air-source heat pumps transfer heat between the inside of a building and the outside air. How Air-Source Heat Pumps Work This diagram of a split-system heat pump heating cycle shows refrigerant circulating through a closed loop that passes through the wall of a house. Inside the house the refrigerant winds through indoor coils, with a fan blowing across them, and outside the house is another fan and another set of coils, the outdoor coils. A compressor is between the coils on one half of the loop, and an expansion valve is between the coils on the other half. The diagram is explained in the caption. In heating mode, an air-source heat pump evaporates a refrigerant in the outdoor coil; as the liquid evaporates it pulls

137

LASL bismuth sulfate thermochemical hydrogen cycle  

DOE Green Energy (OSTI)

The LASL bismuth sulfate cycle is one of a generic class of solid sulfate cycles in which a metal sulfate is substituted for sulfuric acid in a hybrid (partly electrochemical) cycle. This technique avoids the serious materials and heat penalty problems associated with the handling of concentrated acid solutions, and if the electrolyzer is operated at acid concentrations below 50% it may, in principle, lead to a lower cell voltage with subsequent energy savings. Experiment verification of all steps in the cycle has been obtained, particularly for the decomposition of normal bismuth sulfate and lower bismuth oxysulfates. For the substance, Bi/sub 2/O/sub 3/ 2SO/sub 3/, an endothermic requirement of 172 kJ/mol was obtained, which is considerably less than that for other metal sulfate systems. A rotary kiln was used for continuous experiments and our results show decomposition of this compound to Bi/sub 2/O/sub 3/ SO/sub 3/ in under 8 minutes residence time at 1023 K. Preliminary analysis of the cycle's energy balance shows an overall thermal efficiency of greater than 50% when the maximum cycle reaction temperature is 1500 K. The cycle has potential for hydrogen production when coupled with an energy source such as solar or fusion energy.

Cox, K.E.; Jones, W.M.; Peterson, C.L.

1980-01-01T23:59:59.000Z

138

The turbulent cascade and proton heating in the solar wind during solar minimum  

Science Conference Proceedings (OSTI)

Solar wind measurements at 1 AU during the recent solar minimum and previous studies of solar maximum provide an opportunity to study the effects of the changing solar cycle on in situ heating. Our interest is to compare the levels of activity associated with turbulence and proton heating. Large-scale shears in the flow caused by transient activity are a source that drives turbulence that heats the solar wind, but as the solar cycle progresses the dynamics that drive the turbulence and heat the medium are likely to change. The application of third-moment theory to Advanced Composition Explorer (ACE) data gives the turbulent energy cascade rate which is not seen to vary with the solar cycle. Likewise, an empirical heating rate shows no significan changes in proton heating over the cycle.

Coburn, Jesse T.; Smith, Charles W.; Vasquez, Bernard J. [Physics Department and Space Science Center, Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, New Hampshire (United States); Stawarz, Joshua E. [Department of Astrophysical and Planetary Sciences, University of Colorado at Boulder, Boulder, Colorado (United States); Forman, Miriam A. [Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York (United States)

2013-06-13T23:59:59.000Z

139

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

This invention is comprised of a cryogenic refrigerator which cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He/[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, G.W.; Kotsubo, V.Y.

1991-04-02T23:59:59.000Z

140

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He-[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K. 12 figs.

Swift, G.W.; Kotsubo, V.Y.

1992-12-22T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

This invention is comprised of a cryogenic refrigerator which cools a heat source by cyclically concentrating and diluting the amount of {sup 3}He in a single phase {sup 3}He/{sup 4}He solution. The {sup 3}He in superfluid {sup 4}He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid {sup 3}He at an initial concentration in superfluid {sup 4}He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of {sup 4}He while restricting passage of {sup 3}He. The {sup 3}He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, G.W.; Kotsubo, V.Y.

1991-04-02T23:59:59.000Z

142

Superfluid thermodynamic cycle refrigerator  

DOE Patents (OSTI)

A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

Swift, Gregory W. (Santa Fe, NM); Kotsubo, Vincent Y. (La Canada, CA)

1992-01-01T23:59:59.000Z

143

Cycle isolation monitoring  

SciTech Connect

There are many factors to monitor in power plants, but one that is frequently overlooked is cycle isolation. Often this is an area where plant personnel can find 'low hanging fruit' with great return on investment, especially high energy valve leakage. This type of leakage leads to increased heat rate, potential valve damage and lost generation. The fundamental question to ask is 'What is 100 Btu/kW-hr of heat rate worth to your plant? On a 600 MW coal-fired power plant, a 1% leakage can lead to an 81 Btu/kW-hr impact on the main steam cycle and a 64 Btu/kW-hr impact on the hot reheat cycle. The article gives advice on methods to assist in detecting leaking valves and to monitor cycle isolation. A software product, TP. Plus-CIM was designed to estimate flow rates of potentially leaking valves.

Svensen, L.M. III; Zeigler, J.R.; Todd, F.D.; Alder, G.C. [Santee Copper, Moncks Corner, SC (United States)

2009-07-15T23:59:59.000Z

144

Comparison of the Organic Flash Cycle (OFC) to other advanced ...  

Comparison of the Organic Flash Cycle (OFC) to other advanced vapor cycles for intermediate and high temperature waste heat reclamation and solar thermal

145

Optimum cycle parameters of coal fired closed cycle gas turbine in regenerative and combined cycle configurations  

Science Conference Proceedings (OSTI)

This paper presents the methodology developed for the estimation of thermodynamic performance and reports the optimum cycle parameters of coal fired CCGT in regenerative and combined cycle configurations using air, helium and carbon dioxide as working gases. A rigorous approach has been followed for the determination of the cycle efficiency by assuming the specific heat of working gases as a continuous function of temperature for accurate estimation of cycle parameters. 14 refs.

Rao, J.S.

1982-01-01T23:59:59.000Z

146

Fuel Cell Power Model Elucidates Life-Cycle Costs for Fuel Cell-Based Combined Heat, Hydrogen, and Power (CHHP) Production Systems (Fact Sheet)  

Science Conference Proceedings (OSTI)

This fact sheet describes NREL's accomplishments in accurately modeling costs for fuel cell-based combined heat, hydrogen, and power systems. Work was performed by NREL's Hydrogen Technologies and Systems Center.

Not Available

2010-11-01T23:59:59.000Z

147

Exhibit Pre-Show Directory  

Science Conference Proceedings (OSTI)

to maximise the heat transfer to the cathode for best isothermal result. As fuel we use gas, natural or propane, but developing a new APS burner for light oil.

148

Heating fuel choice shows electricity and natural gas roughly ...  

U.S. Energy Information Administration (EIA)

Consumption & Efficiency. ... electric power plant emissions. ... computers, electronics and other devices is powered only by electricity.

149

Definition: Rankine cycle | Open Energy Information  

Open Energy Info (EERE)

Rankine cycle Rankine cycle Jump to: navigation, search Dictionary.png Rankine cycle Sometimes referred to as the steam cycle. Fuel is used to heat a liquid to produce a high pressure gas that expands and produces work, such as turning a turbine; when the turbine is connected to a generator, it produces electricity. Usually water is the liquid used in the Rankine cycle (to produce steam), but other liquids can also be used. The exhaust vapor expelled from the turbine condenses and the liquid is pumped back to the boiler to repeat the cycle.[1][2] View on Wikipedia Wikipedia Definition The Rankine cycle is a mathematical model that is used to predict the performance of steam engines. The Rankine cycle is an idealised thermodynamic cycle of a heat engine that converts heat into mechanical

150

Alternative Cycles for Power Converters  

NLE Websites -- All DOE Office Websites (Extended Search)

expansion in the high pressure turbine by passing it through an additional lead-to-steam heat exchanger (HX). This can be a complication relative to the superheated steam cycle....

151

Feasibility of Thermoelectrics for Waste Heat Recovery in Conventional Vehicles  

DOE Green Energy (OSTI)

Thermoelectric (TE) generators convert heat directly into electricity when a temperature gradient is applied across junctions of two dissimilar metals. The devices could increase the fuel economy of conventional vehicles by recapturing part of the waste heat from engine exhaust and generating electricity to power accessory loads. A simple vehicle and engine waste heat model showed that a Class 8 truck presents the least challenging requirements for TE system efficiency, mass, and cost; these trucks have a fairly high amount of exhaust waste heat, have low mass sensitivity, and travel many miles per year. These factors help maximize fuel savings and economic benefits. A driving/duty cycle analysis shows strong sensitivity of waste heat, and thus TE system electrical output, to vehicle speed and driving cycle. With a typical alternator, a TE system could allow electrification of 8%-15% of a Class 8 truck's accessories for 2%-3% fuel savings. More research should reduce system cost and improve economics.

Smith, K.; Thornton, M.

2009-04-01T23:59:59.000Z

152

Urban Heat Catastrophes  

NLE Websites -- All DOE Office Websites (Extended Search)

The curve shows the heat index, which reflects the combined effect of temperature and humidity. Last year's Chicago heat wave created a great deal of human discomfort and,...

153

Closed-cycle Retrofit Study  

Science Conference Proceedings (OSTI)

EPRI is investigating implications of a potential U.S. Environmental Protection Agency (EPA) Clean Water Act 316(b) rulemaking that would establish "Best Technology Available" (BTA) based on closed-cycle cooling retrofits for facilities with once-through cooling. This report focuses on estimated costs associated with closed-cycle cooling system retrofits that include: 1) capital costs, 2) energy required to operate the closed-cycle system, 3) heat rate penalty, and 4) extended downtime required to retrof...

2011-01-31T23:59:59.000Z

154

Conceptual design of an advanced absorption cycle: the double-effect regenerative absorption refrigeration cycle  

DOE Green Energy (OSTI)

An advanced absorption refrigeration cycle was proposed as a heat-activated refrigeration system. Referred to as the double-effect regenerative absorption cycle of cycle 2R, it improves the performance of the conventional single-effect absorption cycle at high heat source temperatures. The performance of cycle 2R continually improves as input temperatures rise, in contrast to the conventional double-effect absorption cycle that has a sharp cut-off temperature below which it ceases to operate. Cycle 2R operates with two subcycles, the first-effect and the second-effect subcycles.

Dao, K.

1978-09-01T23:59:59.000Z

155

Study of practical cycles for geothermal power plants. Final report  

SciTech Connect

A comparison is made of the performance and cost of geothermal power cycles designed specifically, utilizing existing technology, to exploit the high temperature, high salinity resource at Niland and the moderate temperature, moderately saline resource at East Mesa in California's Imperial Valley. Only two kinds of cycles are considered in the analysis. Both employ a dual flash arrangement and the liberated steam is either utilized directly in a condensing steam turbine or used to heat a secondary working fluid in a closed Rankine (binary) cycle. The performance of several organic fluids was investigated for the closed cycle and the most promising were selected for detailed analysis with the given resource conditions. Results show for the temperature range investigated that if the noncondensible gas content in the brine is low, a dual flash condensing steam turbine cycle is potentially better in terms of resource utilization than a dual flash binary cycle. (The reverse is shown to be true when the brine is utilized directly for heat exchange.) It is also shown that despite the higher resource temperature, the performance of the dual flash binary cycle at Niland is degraded appreciably by the high salinity and its output per unit of brine flow is almost 20 percent lower than that of the steam turbine cycle at East Mesa. Turbine designs were formulated and costs established for power plants having a nominal generating capacity of 50 MW. Three cycles were analyzed in detail. At East Mesa a steam turbine and a binary cycle were compared. At Niland only the binary cycle was analyzed since the high CO/sub 2/ content in the brine precludes the use of a steam turbine there. In each case only the power island equipment was considered and well costs and the cost of flash separators, steam scrubbers and piping to the power plant boundary were excluded from the estimate.

Eskesen, J.H.

1977-04-01T23:59:59.000Z

156

Study of practical cycles for geothermal power plants. Final report  

DOE Green Energy (OSTI)

A comparison is made of the performance and cost of geothermal power cycles designed specifically, utilizing existing technology, to exploit the high temperature, high salinity resource at Niland and the moderate temperature, moderately saline resource at East Mesa in California's Imperial Valley. Only two kinds of cycles are considered in the analysis. Both employ a dual flash arrangement and the liberated steam is either utilized directly in a condensing steam turbine or used to heat a secondary working fluid in a closed Rankine (binary) cycle. The performance of several organic fluids was investigated for the closed cycle and the most promising were selected for detailed analysis with the given resource conditions. Results show for the temperature range investigated that if the noncondensible gas content in the brine is low, a dual flash condensing steam turbine cycle is potentially better in terms of resource utilization than a dual flash binary cycle. (The reverse is shown to be true when the brine is utilized directly for heat exchange.) It is also shown that despite the higher resource temperature, the performance of the dual flash binary cycle at Niland is degraded appreciably by the high salinity and its output per unit of brine flow is almost 20 percent lower than that of the steam turbine cycle at East Mesa. Turbine designs were formulated and costs established for power plants having a nominal generating capacity of 50 MW. Three cycles were analyzed in detail. At East Mesa a steam turbine and a binary cycle were compared. At Niland only the binary cycle was analyzed since the high CO/sub 2/ content in the brine precludes the use of a steam turbine there. In each case only the power island equipment was considered and well costs and the cost of flash separators, steam scrubbers and piping to the power plant boundary were excluded from the estimate.

Eskesen, J.H.

1977-04-01T23:59:59.000Z

157

Study of practical cycles for geothermal power plants. Interim report, June 15, 1975-March 31, 1976  

DOE Green Energy (OSTI)

The preliminary analysis is described in a study of practical cycles for geothermal power plants. The analysis is based on three different brines whose temperatures and composition span the range that is of practical interest for power generation. Only two kinds of cycles were considered in the analysis - the steam turbine cycle and the binary cycle, in which energy from the geothermal fluid is transferred to a secondary working fluid in a closed Rankine cycle. The performance of several condidate working fluids has been investigated, and the most attracive binary cycles have been selected for the various resource conditions. The results show that if brine is utilized directly in the primary heat exchange process with the secondary working fluid, the binary cycle is potentially better in terms of resource utilization than a dual flash steam turbine cycle. However, if the brine is flashed to steam and the steam is used for the heat exchange process, the steam turbine cycle will produce more power per pound of brine flow. Preliminary turbine designs have been formulated for steam and also for the most promising working fluids in the secondary or binary cycle. For all cycle configurations at least 50 MW of electrical power can be generated by a single unit without exceeding mechanical design or manufacturing limitations even when the resource temperature is as low as 400/sup 0/F. Plant economics were not considered.

Eskesen, J.H.

1976-04-01T23:59:59.000Z

158

Nuclear fuel cycle costs  

Science Conference Proceedings (OSTI)

The costs for the back-end of the nuclear fuel cycle, which were developed as part of the Nonproliferation Alternative Systems Assessment Program (NASAP), are presented. Total fuel cycle costs are given for the pressurized water reactor once-through and fuel recycle systems, and for the liquid-metal fast breeder reactor system. These calculations show that fuel cycle costs are a small part of the total power costs. For breeder reactors, fuel cycle costs are about half that of the present once-through system. The total power cost of the breeder reactor system is greater than that of light-water reactor at today's prices for uranium and enrichment.

Burch, W.D.; Haire, M.J.; Rainey, R.H.

1982-02-01T23:59:59.000Z

159

Photovoltaic roof heat flux  

E-Print Network (OSTI)

of ~24°C, indicating that heat conduction was small. T h i sday, indicating large heat conduction a n d storage. Control2.1.3 showed that conduction heat flux through the roof was

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

160

Refrigerant Phase-Change Stirling-Cycle Solar Power Towers  

Science Conference Proceedings (OSTI)

This paper firstly introduces the principles of Refrigerant Phase-Change Stirling-Cycle solar power towers This heat engines use solar reservoire. When the refrigerant in an engine cylinder absorbs heat from high-temperature heat sources, refrigerant ... Keywords: refrigerant phase-change cycle, heat engines, solar power tower, finite-time thermodynamics

Dezhong Huang

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

TITAN'S TRANSPORT-DRIVEN METHANE CYCLE  

SciTech Connect

The mechanisms behind the occurrence of large cloud outbursts and precipitation on Titan have been disputed. A global- and annual-mean estimate of surface fluxes indicated only 1% of the insolation, or {approx}0.04 W m{sup -2}, is exchanged as sensible and/or latent fluxes. Since these fluxes are responsible for driving atmospheric convection, it has been argued that moist convection should be quite rare and precipitation even rarer, even if evaporation globally dominates the surface-atmosphere energy exchange. In contrast, climate simulations indicate substantial cloud formation and/or precipitation. We argue that the top-of-atmosphere (TOA) radiative imbalance is diagnostic of horizontal heat transport by Titan's atmosphere, and thus constrains the strength of the methane cycle. Simple calculations show the TOA radiative imbalance is {approx}0.5-1 W m{sup -2} in Titan's equatorial region, which implies 2-3 MW of latitudinal heat transport by the atmosphere. Our simulation of Titan's climate suggests this transport may occur primarily as latent heat, with net evaporation at the equator and net accumulation at higher latitudes. Thus, the methane cycle could be 10-20 times previous estimates. Opposing seasonal transport at solstices, compensation by sensible heat transport, and focusing of precipitation by large-scale dynamics could further enhance the local, instantaneous strength of Titan's methane cycle by a factor of several. A limited supply of surface liquids in regions of large surface radiative imbalance may throttle the methane cycle, and if so, we predict more frequent large storms over the lakes district during Titan's northern summer.

Mitchell, Jonathan L. [Department of Earth and Space Sciences, Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA 90095 (United States)

2012-09-10T23:59:59.000Z

162

Combined-cycle power tower  

DOE Green Energy (OSTI)

This paper evaluates a new power tower concept that offers significant benefits for commercialization of power tower technology. The concept uses a molten nitrate salt centralreceiver plant to supply heat, in the form of combustion air preheat, to a conventional combined-cycle power plant. The evaluation focused on first commercial plants, examined three plant capacities (31, 100, and 300 MWe), and compared these plants with a solar-only 100-MWe plant and with gas-only combined-cycle plants in the same three capacities. Results of the analysis point to several benefits relative to the solar-only plant including low energy cost for first plants, low capital cost for first plants, reduced risk with respect to business uncertainties, and the potential for new markets. In addition, the concept appears to have minimal technology development requirements. Significantly, the results show that it is possible to build a first plant with this concept that can compete with existing gas-only combined-cycle plants.

Bohn, M.S.; Williams, T.A.; Price, H.W.

1994-10-01T23:59:59.000Z

163

4-H Show Lamb Guide  

E-Print Network (OSTI)

This pocket guide is a reference for 4-H members who raise show lambs. The manual covers facilities and equipment needs, lamb selection, nutrition, health, management and feeding, fitting and showing.

Craddock, Frank; Stultz, Ross

1998-11-30T23:59:59.000Z

164

Efficiency combined cycle power plant  

SciTech Connect

This patent describes a method of operating a combined cycle power plant. It comprises: flowing exhaust gas from a combustion turbine through a heat recovery steam generator (HRSG); flowing feed water through an economizer section of the HRSG at a flow rate and providing heated feed water; flowing a first portion of the heated feed water through an evaporator section of the HRSG and producing saturated steam at a production rate, the flow rate of the feed water through the economizer section being greater than required to sustain the production rate of steam in the evaporator section; flowing fuel for the turbine through a heat exchanger; and, flowing a second portion of the heated feed water provided by the economizer section through the heat exchanger then to an inlet of the economizer section, thereby heating the fuel flowing through the heat exchanger.

Pavel, J.; Meyers, G.A.; Baldwin, T.S.

1990-06-12T23:59:59.000Z

165

Analysis of mass transfer processes in geothermal power cycles utilizing direct contact heat exchange. Report of work, September 21, 1978 to September 30, 1979  

DOE Green Energy (OSTI)

A computer program was developed which calculates the isobutane content of the spent brine and the liquid-vapor distribution of carbon dioxide and hydrogen sulfide throughout the components of a geothermal power plant using direct contact heat exchange. The program model assumes separate boiler and preheater vessels, with the preheater being a spray tower. The condenser model is a horizontal tube surface condenser with condensation on the outside. The program was written in Fortran language. The Fortran source deck consists of 976 cards. The program utilizes 320K for compilation and 72K for execution on an IBM 370/3031. Sample cases were run which illustrate the effects of salt concentration in the brine and isobutane-to-brine ratio on isobutane and noncondensible gas content of the spent brine.

Knight, J.J.; Perona, J.J.

1979-01-01T23:59:59.000Z

166

Evaluation and Optimization of a Supercritical Carbon Dioxide Power Conversion Cycle for Nuclear Applications  

Science Conference Proceedings (OSTI)

There have been a number of studies involving the use of gases operating in the supercritical mode for power production and process heat applications. Supercritical carbon dioxide (CO2) is particularly attractive because it is capable of achieving relatively high power conversion cycle efficiencies in the temperature range between 550°C and 750°C. Therefore, it has the potential for use with any type of high-temperature nuclear reactor concept, assuming reactor core outlet temperatures of at least 550°C. The particular power cycle investigated in this paper is a supercritical CO2 Recompression Brayton Cycle. The CO2 Recompression Brayton Cycle can be used as either a direct or indirect power conversion cycle, depending on the reactor type and reactor outlet temperature. The advantage of this cycle when compared to the helium Brayton Cycle is the lower required operating temperature; 550°C versus 850°C. However, the supercritical CO2 Recompression Brayton Cycle requires an operating pressure in the range of 20 MPa, which is considerably higher than the required helium Brayton cycle operating pressure of 8 MPa. This paper presents results of analyses performed using the UniSim process analyses software to evaluate the performance of the supercritical CO2 Brayton Recompression Cycle for different reactor outlet temperatures. The UniSim model assumed a 600 MWt reactor power source, which provides heat to the power cycle at a maximum temperature of between 550°C and 750°C. The UniSim model used realistic component parameters and operating conditions to model the complete power conversion system. CO2 properties were evaluated, and the operating range for the cycle was adjusted to take advantage of the rapidly changing conditions near the critical point. The UniSim model was then optimized to maximize the power cycle thermal efficiency at the different maximum power cycle operating temperatures. The results of the analyses showed that power cycle thermal efficiencies in the range of 40 to 50% can be achieved.

Edwin A. Harvego; Michael G. McKellar

2011-05-01T23:59:59.000Z

167

Supercritical carbon dioxide cycle control analysis.  

SciTech Connect

This report documents work carried out during FY 2008 on further investigation of control strategies for supercritical carbon dioxide (S-CO{sub 2}) Brayton cycle energy converters. The main focus of the present work has been on investigation of the S-CO{sub 2} cycle control and behavior under conditions not covered by previous work. An important scenario which has not been previously calculated involves cycle operation for a Sodium-Cooled Fast Reactor (SFR) following a reactor scram event and the transition to the primary coolant natural circulation and decay heat removal. The Argonne National Laboratory (ANL) Plant Dynamics Code has been applied to investigate the dynamic behavior of the 96 MWe (250 MWt) Advanced Burner Test Reactor (ABTR) S-CO{sub 2} Brayton cycle following scram. The timescale for the primary sodium flowrate to coast down and the transition to natural circulation to occur was calculated with the SAS4A/SASSYS-1 computer code and found to be about 400 seconds. It is assumed that after this time, decay heat is removed by the normal ABTR shutdown heat removal system incorporating a dedicated shutdown heat removal S-CO{sub 2} pump and cooler. The ANL Plant Dynamics Code configured for the Small Secure Transportable Autonomous Reactor (SSTAR) Lead-Cooled Fast Reactor (LFR) was utilized to model the S-CO{sub 2} Brayton cycle with a decaying liquid metal coolant flow to the Pb-to-CO{sub 2} heat exchangers and temperatures reflecting the decaying core power and heat removal by the cycle. The results obtained in this manner are approximate but indicative of the cycle transient performance. The ANL Plant Dynamics Code calculations show that the S-CO{sub 2} cycle can operate for about 400 seconds following the reactor scram driven by the thermal energy stored in the reactor structures and coolant such that heat removal from the reactor exceeds the decay heat generation. Based on the results, requirements for the shutdown heat removal system may be defined. In particular, the peak heat removal capacity of the shutdown heat removal loop may be specified to be 1.1 % of the nominal reactor power. An investigation of the oscillating cycle behavior calculated by the ANL Plant Dynamics Code under specific conditions has been carried out. It has been found that the calculation of unstable operation of the cycle during power reduction to 0 % may be attributed to the modeling of main compressor operation. The most probable reason for such instabilities is the limit of applicability of the currently used one-dimensional compressor performance subroutines which are based on empirical loss coefficients. A development of more detailed compressor design and performance models is required and is recommended for future work in order to better investigate and possibly eliminate the calculated instabilities. Also, as part of such model development, more reliable surge criteria should be developed for compressor operation close to the critical point. It is expected that more detailed compressor models will be developed as a part of validation of the Plant Dynamics Code through model comparison with the experiment data generated in the small S-CO{sub 2} loops being constructed at Barber-Nichols Inc. and Sandia National Laboratories (SNL). Although such a comparison activity had been planned to be initiated in FY 2008, data from the SNL compression loop currently in operation at Barber Nichols Inc. has not yet become available by the due date of this report. To enable the transient S-CO{sub 2} cycle investigations to be carried out, the ANL Plant Dynamics Code for the S-CO{sub 2} Brayton cycle was further developed and improved. The improvements include further optimization and tuning of the control mechanisms as well as an adaptation of the code for reactor systems other than the Lead-Cooled Fast Reactor (LFR). Since the focus of the ANL work on S-CO{sub 2} cycle development for the majority of the current year has been on the applicability of the cycle to SFRs, work has started on modification of the ANL Plant Dynamics Code to allow

Moisseytsev, A.; Sienicki, J. J. (Nuclear Engineering Division)

2011-04-11T23:59:59.000Z

168

PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP  

E-Print Network (OSTI)

by the heat pump effect. The Stirling engine/Rankine cycle refrigeration loop heat pump being developed would and replacement segments of each. The Preliminary Design was completed in 1975. During this phase, several. As a result of this phase, a Stirling/ Rankine, prime mover/refrigeration cycle approach was selected

Oak Ridge National Laboratory

169

Optimization and Comparison of Direct and Indirect Supercritical Carbon Dioxide Power Plant Cycles for Nuclear Applications  

Science Conference Proceedings (OSTI)

There have been a number of studies involving the use of gases operating in the supercritical mode for power production and process heat applications. Supercritical carbon dioxide (CO2) is particularly attractive because it is capable of achieving relatively high power conversion cycle efficiencies in the temperature range between 550 C and 750 C. Therefore, it has the potential for use with any type of high-temperature nuclear reactor concept, assuming reactor core outlet temperatures of at least 550 C. The particular power cycle investigated in this paper is a supercritical CO2 Recompression Brayton Cycle. The CO2 Recompression Brayton Cycle can be used as either a direct or indirect power conversion cycle, depending on the reactor type and reactor outlet temperature. The advantage of this cycle when compared to the helium Brayton cycle is the lower required operating temperature; 550 C versus 850 C. However, the supercritical CO2 Recompression Brayton Cycle requires an operating pressure in the range of 20 MPa, which is considerably higher than the required helium Brayton cycle operating pressure of 8 MPa. This paper presents results of analyses performed using the UniSim process analyses software to evaluate the performance of both a direct and indirect supercritical CO2 Brayton Recompression cycle for different reactor outlet temperatures. The direct supercritical CO2 cycle transferred heat directly from a 600 MWt reactor to the supercritical CO2 working fluid supplied to the turbine generator at approximately 20 MPa. The indirect supercritical CO2 cycle assumed a helium-cooled Very High Temperature Reactor (VHTR), operating at a primary system pressure of approximately 7.0 MPa, delivered heat through an intermediate heat exchanger to the secondary indirect supercritical CO2 Brayton Recompression cycle, again operating at a pressure of about 20 MPa. For both the direct and indirect cycles, sensitivity calculations were performed for reactor outlet temperature between 550 C and 850 C. The UniSim models used realistic component parameters and operating conditions to model the complete reactor and power conversion systems. CO2 properties were evaluated, and the operating ranges of the cycles were adjusted to take advantage of the rapidly changing properties of CO2 near the critical point. The results of the analyses showed that, for the direct supercritical CO2 power cycle, thermal efficiencies in the range of 40 to 50% can be achieved. For the indirect supercritical CO2 power cycle, thermal efficiencies were approximately 10% lower than those obtained for the direct cycle over the same reactor outlet temperature range.

Edwin A. Harvego; Michael G. McKellar

2011-11-01T23:59:59.000Z

170

Evaluation of water source heat pumps for the Juneau, Alaska Area  

Science Conference Proceedings (OSTI)

The purposes of this project were to evaluate the technical and economic feasibility of water source heat pumps (WSHP) for use in Juneau, Alaska and to identify potential demonstration projects to verify their feasibility. Information is included on the design, cost, and availability of heat pumps, possible use of seawater as a heat source, heating costs with WSHP and conventional space heating systems, and life cycle costs for WSHP-based heating systems. The results showed that WSHP's are technically viable in the Juneau area, proper installation and maintenance is imperative to prevent equipment failures, use of WSHP would save fuel oil but increase electric power consumption. Life cycle costs for WSHP's are about 8% above that for electric resistance heating systems, and a field demonstration program to verify these results should be conducted. (LCL)

Jacobsen, J.J.; King, J.C.; Eisenhauer, J.L.; Gibson, C.I.

1980-07-01T23:59:59.000Z

171

Definition: Brayton cycle | Open Energy Information  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Definition Edit with form History Facebook icon Twitter icon » Definition: Brayton cycle Jump to: navigation, search Dictionary.png Brayton cycle A thermodynamic cycle using constant pressure, heat addition and rejection. Fuel and a compressor are used to heat and increase the pressure of a gas; the gas expands and spins the blades of a turbine, which, when connected to a generator, generates electricity.[1][2] View on Wikipedia Wikipedia Definition The Brayton cycle is a thermodynamic cycle that describes the workings of a constant pressure heat engine. Gas turbine engines and airbreathing jet engines use the Brayton Cycle. Although the Brayton cycle

172

The Kalina cycle and similar cycles for geothermal power production  

SciTech Connect

This report contains a brief discussion of the mechanics of the Kalina cycle and ideas to extend the concept to other somewhat different cycles. A modified cycle which has a potential heat rejection advantage but little or no performance improvement is discussed. Then, the results of the application of the Kalina cycle and the modified cycle to a geothermal application (360/degree/F resource) are discussed. The results are compared with published results for the Kalina cycle with high temperature sources and estimates about performance at the geothermal temperatures. Finally, the conclusions of this scoping work are given along with recommendations of the direction of future work in this area. 11 refs., 4 figs., 1 tab.

Bliem, C.J.

1988-09-01T23:59:59.000Z

173

Applied heat transfer  

Science Conference Proceedings (OSTI)

Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)

Ganapathy, V.

1982-01-01T23:59:59.000Z

174

Absorption heat pump system  

DOE Patents (OSTI)

An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

1984-01-01T23:59:59.000Z

175

ZEBRAlliance Research Project Shows Promising Results | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

on the homes. The project looked at the efficiency of two technologies: a foundation heat exchanger and a ground- source integrated heat pump. Other experiments were conducted...

176

Process Heating  

Science Conference Proceedings (OSTI)

This technical update uses real world examples to discuss applications of electrotechnology in industrial process heating and to highlight some of the emerging technologies in this field. These emerging technologies, when implemented in a plant, will provide significant energy savings as well as increase productivity. The report presents three case studies of successful implementation of two different electric process-heating technologies in three different industries. The case studies show that in some ...

2011-12-07T23:59:59.000Z

177

Advanced regenerative absorption refrigeration cycles  

DOE Patents (OSTI)

Multi-effect regenerative absorption cycles which provide a high coefficient of performance (COP) at relatively high input temperatures. An absorber-coupled double-effect regenerative cycle (ADR cycle) (10) is provided having a single-effect absorption cycle (SEA cycle) (11) as a topping subcycle and a single-effect regenerative absorption cycle (1R cycle) (12) as a bottoming subcycle. The SEA cycle (11) includes a boiler (13), a condenser (21), an expansion device (28), an evaporator (31), and an absorber (40), all operatively connected together. The 1R cycle (12) includes a multistage boiler (48), a multi-stage resorber (51), a multisection regenerator (49) and also uses the condenser (21), expansion device (28) and evaporator (31) of the SEA topping subcycle (11), all operatively connected together. External heat is applied to the SEA boiler (13) for operation up to about 500 degrees F., with most of the high pressure vapor going to the condenser (21) and evaporator (31) being generated by the regenerator (49). The substantially adiabatic and isothermal functioning of the SER subcycle (12) provides a high COP. For higher input temperatures of up to 700 degrees F., another SEA cycle (111) is used as a topping subcycle, with the absorber (140) of the topping subcycle being heat coupled to the boiler (13) of an ADR cycle (10). The 1R cycle (12) itself is an improvement in that all resorber stages (50b-f) have a portion of their output pumped to boiling conduits (71a-f) through the regenerator (49), which conduits are connected to and at the same pressure as the highest pressure stage (48a) of the 1R multistage boiler (48).

Dao, Kim (14 Nace Ave., Piedmont, CA 94611)

1990-01-01T23:59:59.000Z

178

Property Libraries for Working Fluids for Calculating Heat ...  

Science Conference Proceedings (OSTI)

... properties of working fluids can be used for the daily work of an engineer who calculates heat cycles, steam or gas turbines, boilers, heat pumps or ...

2006-07-20T23:59:59.000Z

179

Residential Energy Consumption Survey data show decreased ...  

U.S. Energy Information Administration (EIA)

Energy Information Administration ... solar, wind, geothermal, ... Improvements in efficiency for space heating, ...

180

Heat pipe array heat exchanger  

DOE Patents (OSTI)

A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

Reimann, Robert C. (Lafayette, NY)

1987-08-25T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Absorption Heat Pump Basics | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Absorption Heat Pump Basics Absorption Heat Pump Basics Absorption Heat Pump Basics August 19, 2013 - 11:11am Addthis Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps. There are also absorption coolers available that work on the same principal, but are not reversible and cannot serve as a heat source. These are also called gas-fired coolers. How Absorption Heat Pumps Work Residential absorption heat pumps use an ammonia-water absorption cycle to provide heating and cooling. As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one coil to release its heat; its

182

Absorption Heat Pumps | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Absorption Heat Pumps Absorption Heat Pumps Absorption Heat Pumps June 24, 2012 - 2:11pm Addthis Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps. There are also absorption (or gas-fired) coolers available that work on the same principle. Unlike some absorption heat pumps, however, these are not reversible and cannot serve as a heat source. Residential absorption heat pumps use an ammonia-water absorption cycle to provide heating and cooling. As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one coil to release its heat; its

183

Absorption Heat Pumps | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Absorption Heat Pumps Absorption Heat Pumps Absorption Heat Pumps June 24, 2012 - 2:11pm Addthis Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps. There are also absorption (or gas-fired) coolers available that work on the same principle. Unlike some absorption heat pumps, however, these are not reversible and cannot serve as a heat source. Residential absorption heat pumps use an ammonia-water absorption cycle to provide heating and cooling. As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one coil to release its heat; its

184

System Design and Experimental Development of the Kalina Cycle Technology  

E-Print Network (OSTI)

For any given heat source, only a portion of the thermal energy may be converted into useful work. The amount of energy which may be converted from any form into mechanical energy is referred to as exergy. The ratio of the system's mechanical work to the exergy of the heat source is referred to as exergetical or thermodynamic efficiency. As heat sources vary in their temperature and heat exchange process, there is a particular thermodynamic cycle that best fits each system's border conditions. The Kalina cycle technology seeks to develop a set of systems and cycles with which to optimize a particular heat source; e.g., coal, geothermal, waste heat, nuclear, etc.

Kalina, A. I.

1987-09-01T23:59:59.000Z

185

High-speed thermal cycling system and method of use  

DOE Patents (OSTI)

A thermal cycling system and method of use are described. The thermal cycling system is based on the-circulation of temperature-controlled water directly to the underside of thin-walled polycarbonate microtiter plates. The water flow is selected from a manifold fed by pumps from heated reservoirs. The plate wells are loaded with typically 15-20 .mu.l of reagent mix for the PCR process. Heat transfer through the thin polycarbonate is sufficiently rapid that the contents reach thermal equilibrium with the water in less than 15 seconds. Complete PCR amplification runs of 40 three-step cycles have been performed in as little as 14.5 minutes, with the results showing substantially enhanced specificity compared to conventional technology requiring run times in excess of 100 minutes. The plate clamping station is designed to be amenable to robotic loading and unloading of the system. It includes a heated lid, thus eliminating the need for mineral oil overlay of the reactants. The present system includes three or more plate holder stations, fed from common reservoirs but operating with independent switching cycles. The system can be modularly expanded.

Hansen, Anthony D. A. (Berkely, CA); Jaklevic, Joseph M. (Lafayette, CA)

1996-01-01T23:59:59.000Z

186

High-speed thermal cycling system and method of use  

DOE Patents (OSTI)

A thermal cycling system and method of use are described. The thermal cycling system is based on the circulation of temperature-controlled water directly to the underside of thin-walled polycarbonate plates. The water flow is selected from a manifold fed by pumps from heated reservoirs. The plate wells are loaded with typically 15-20 microliters of reagent mix for the PCR process. Heat transfer through the thin polycarbonate is sufficiently rapid that the contents reach thermal equilibrium with the water in less than 15 seconds. Complete PCR amplification runs of 40 three-step cycles have been performed in as little as 14.5 minutes, with the results showing substantially enhanced specificity compared to conventional technology requiring run times in excess of 100 minutes. The plate clamping station is designed to be amenable to robotic loading and unloading of the system. It includes a heated lid, thus eliminating the need for mineral oil overlay of the reactants. The present system includes three or more plate holder stations, fed from common reservoirs but operating with independent switching cycles. The system can be modularly expanded. 13 figs.

Hansen, A.D.A.; Jaklevic, J.M.

1996-04-16T23:59:59.000Z

187

Highly efficient 6-stroke engine cycle with water injection  

Science Conference Proceedings (OSTI)

A six-stroke engine cycle having improved efficiency. Heat is recovered from the engine combustion gases by using a 6-stroke engine cycle in which combustion gases are partially vented proximate the bottom-dead-center position of the fourth stroke cycle, and water is injected proximate the top-dead-center position of the fourth stroke cycle.

Szybist, James P; Conklin, James C

2012-10-23T23:59:59.000Z

188

Thermally activated heat pumps  

SciTech Connect

This article describes research to develop efficient gas-fired heat pumps heat and cool buildings without CFCs. Space heating and cooling use 46% of all energy consumed in US buildings. Air-conditioning is the single leading cause of peak demand for electricity and is a major user of chlorofluorocarbons (CFCs). Advanced energy conversion technology can save 50% of this energy and eliminate CFCs completely. Besides saving energy, advanced systems substantially reduce emissions of carbon dioxide (a greenhouse gas), sulfur dioxide, and nitrogen oxides, which contribute to smog and acid rain. These emissions result from the burning of fossil fuels used to generate electricity. The Office of Building Technologies (OBT) of the US Department of Energy supports private industry`s efforts to improve energy efficiency and increase the use of renewable energy in buildings. To help industry, OBT, through the Oak Ridge National Laboratory, is currently working on thermally activated heat pumps. OBT has selected the following absorption heat pump systems to develop: generator-absorber heat-exchange (GAX) cycle for heating-dominated applications in residential and light commercial buildings; double-condenser-coupled (DCC) cycle for commercial buildings. In addition, OBT is developing computer-aided design software for investigating the absorption cycle.

NONE

1995-05-01T23:59:59.000Z

189

Distributed Generation with Heat Recovery and Storage  

E-Print Network (OSTI)

selection of on-site power generation with combined heat andsingle-cycle thermal power generation is typically lesshighly centralized power generation and delivery system

Siddiqui, Afzal S.; Marnay, Chris; Firestone, Ryan M.; Zhou, Nan

2008-01-01T23:59:59.000Z

190

State Home Oil Weatherization (SHOW) Program | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Home Oil Weatherization (SHOW) Program Home Oil Weatherization (SHOW) Program State Home Oil Weatherization (SHOW) Program < Back Eligibility Multi-Family Residential Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Sealing Your Home Design & Remodeling Windows, Doors, & Skylights Ventilation Manufacturing Maximum Rebate $500/household Program Info State Oregon Program Type State Rebate Program Rebate Amount Blower-door test - 100% of the cost up to $100. All other technologies are 25% of the total cost, up to $150 or $500, depending on the upgrade. Provider Oregon Department of Energy Oregon homeowners and renters who heat with oil, wood, propane, kerosene, or butane are eligible for home weatherization rebates of up to $500. A

191

Life Cycles of Moist Baroclinic Eddies  

Science Conference Proceedings (OSTI)

The interaction between moisture and baroclinic eddies was examined through eddy life-cycle experiments using a global, primitive equation model. How condensation affects the structural evolution of eddies, their fluxes of heat, moisture, and ...

William J. Gutowski Jr.; Lee E. Branscome; Douglas A. Stewart

1992-02-01T23:59:59.000Z

192

A Modification of the Atmospheric Energy Cycle  

Science Conference Proceedings (OSTI)

A modification is made of the conventional energy cycle by combining the eddy flux convergence and the mean meridional circulation terms in the mean momentum and heat equations. The combined terms are interpreted as the effective flux ...

Yoshikazu Hayashi

1987-08-01T23:59:59.000Z

193

Water Recovery From Humidified Power Cycles  

Science Conference Proceedings (OSTI)

Recovery of water from humidified cycles using a scrubber-desaturator, and the recovered water's clean-up and reuse have been shown to be practical, with comparatively low increases in capital costs and heat rates.

1998-02-09T23:59:59.000Z

194

Binary Cycle Power Plant | Open Energy Information  

Open Energy Info (EERE)

Binary Cycle Power Plant Binary Cycle Power Plant (Redirected from Binary Cycle Power Plants) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Binary Cycle Power Plant General List of Binary Plants Binary power plant process diagram - DOE EERE 2012 Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units. Low to moderately heated (below 400°F) geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point that water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines and subsequently, the generators.

195

Binary Cycle Power Plant | Open Energy Information  

Open Energy Info (EERE)

Binary Cycle Power Plant Binary Cycle Power Plant (Redirected from Binary) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Binary Cycle Power Plant General List of Binary Plants Binary power plant process diagram - DOE EERE 2012 Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units. Low to moderately heated (below 400°F) geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point that water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines and subsequently, the generators. Binary cycle power plants are closed-loop systems and virtually nothing

196

Direct fired power cycle  

SciTech Connect

A method for implementing a thermodynamic cycle is described comprising the steps of: expanding a gaseous working stream to transform its energy into usable form; removing from the expanded gaseous working stream a withdrawal stream; combining the withdrawal stream with a lean stream, having a higher content of a higher-boiling component than is contained in the withdrawal stream, to form a composite stream; condensing the composite stream to provide heat; separating the composite stream to form a liquid stream; forming an oncoming liquid working stream that evaporates at a temperature lower than the temperature at which the composite stream condenses; and evaporating the oncoming liquid working stream, using the heat produced by condensing the composite stream, to form the gaseous working stream.

Kalina, A.I.

1988-03-22T23:59:59.000Z

197

Faster, More Efficient Redox Cycle to Split Water or ...  

heating or cooling is required between the respective ... using concentrated solar energy to provide thermal ... More Efficient Redox Cycle to Split W ...

198

Projections of Full-Fuel-Cycle Energy and Emissions Metrics  

E-Print Network (OSTI)

Nuclear Fuel ..to characterize the nuclear fuel cycle (Wu et al. Renewableby the heat content of nuclear fuel. In this analysis we use

Coughlin, Katie

2013-01-01T23:59:59.000Z

199

The Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Cycle Print E-mail U.S. Carbon Cycle Science Program U.S. Carbon Cycle Science Program The U.S. Carbon Cycle Science Program, in consultation with the Carbon Cycle...

200

Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Carbon Cycle Carbon Cycle Latest Global Carbon Budget Estimates Including CDIAC Estimates Terrestrial Carbon Management Data Sets and Analyses Carbon Dioxide Emissions from Fossil-Fuel Consumption and Cement Manufacture, (2011) Annual Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) Monthly Fossil-Fuel CO2 Emissions: Mass of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) Annual Fossil-Fuel CO2 Emissions: Global Stable Carbon Isotopic Signature (2012) Monthly Fossil-Fuel CO2 Emissions: Isomass (δ 13C) of Emissions Gridded by One Degree Latitude by One Degree Longitude (2012) AmeriFlux - Terrestrial Carbon Dioxide, Water Vapor, and Energy Balance Measurements Estimates of Monthly CO2 Emissions and Associated 13C/12C Values

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Cascade Reverse Osmosis Air Conditioning System: Cascade Reverse Osmosis and the Absorption Osmosis Cycle  

SciTech Connect

BEETIT Project: Battelle is developing a new air conditioning system that uses a cascade reverse osmosis (RO)-based absorption cycle. Analyses show that this new cycle can be as much as 60% more efficient than vapor compression, which is used in 90% of air conditioners. Traditional vapor-compression systems use polluting liquids for a cooling effect. Absorption cycles use benign refrigerants such as water, which is absorbed in a salt solution and pumped as liquid—replacing compression of vapor. The refrigerant is subsequently separated from absorbing salt using heat for re-use in the cooling cycle. Battelle is replacing thermal separation of refrigerant with a more efficient reverse osmosis process. Research has shown that the cycle is possible, but further investment will be needed to reduce the number of cascade reverse osmosis stages and therefore cost.

None

2010-09-01T23:59:59.000Z

202

Definition: Thermodynamic cycle | Open Energy Information  

Open Energy Info (EERE)

Thermodynamic cycle Thermodynamic cycle Jump to: navigation, search Dictionary.png Thermodynamic cycle A process in which a fluid (water, air, ammonia, etc) successively changes state (from a liquid to a gas and back to a liquid) for the purpose of producing or transferring energy.[1] View on Wikipedia Wikipedia Definition A thermodynamic cycle consists of a collection of thermodynamic processes transferring heat and work, while varying pressure, temperature, and other state variables, eventually returning a system to its initial state. In the process of going through this cycle, the system may perform work on its surroundings, therefore acting as a heat engine. State quantities depend only on the thermodynamic state, and cumulative variation of such properties adds up to zero during a cycle. Process quantities (or

203

Water Vapor and Mechanical Work: A Comparison of Carnot and Steam Cycles OLIVIER PAULUIS  

E-Print Network (OSTI)

Water Vapor and Mechanical Work: A Comparison of Carnot and Steam Cycles OLIVIER PAULUIS Center in the atmosphere is discussed here by comparing two idealized heat engines: the Carnot cycle and the steam cycle. A steam cycle transports water from a warm moist source to a colder dryer sink. It acts as a heat engine

Pauluis, Olivier M.

204

The Framatome ANP Indirect-Cycle Very High Temperature Reactor  

SciTech Connect

Framatome ANP is developing a Very High Temperature Reactor (VHTR) design, relying on its previous experience with high temperature reactor designs, from its participation in the MODUL and the GT-MHR designs. The Framatome ANP VHTR design is based on an indirect cycle coupled to an 'off-the-shelf' combined cycle gas turbine. Although direct cycle HTR's are being promoted for their high efficiency, preliminary evaluations show that the Framatome ANP design efficiency is on par with a direct cycle while avoiding PGS (Power Generation System) developments and keeping the PGS contamination free. This concept was independently evaluated with sensitivity analysis by EDF. Moreover, the nuclear heat source of the indirect cycle could also be used to qualify the direct cycle components without risk of contamination behind the IHX, thus assisting in the preparation for the later introduction of that technology. Relying to the maximum extent on available technology, the Framatome ANP VHTR plant can demonstrate high-efficiency electricity generation and carbon-free hydrogen production. (authors)

Copsey, Bernie [Framatome ANP, Inc., 3315 Old Forest Road Lynchburg, VA (United States); Lecomte, Michel [Framatome ANP, SAS, Tour AREVA Paris, La Defense (France); Brinkmann, Gerd [Framatome ANP, GmbH, 49 (9131) 18-96630, Erlangen (Germany); Capitaine, Alain; Deberne, Nicolas [EDF/SEPTEN, Villeurbanne (France)

2004-07-01T23:59:59.000Z

205

Heat Pump for High School Heat Recovery  

E-Print Network (OSTI)

The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system has good economic property, can conserve energy and protects the environment. Therefore, there is a large potential for its development. In addition, three projects using this system are presented and contrasted, which indicate that a joint system that uses both the heat pump and heat exchanger to recycle waste heat is a preferable option.

Huang, K.; Wang, H.; Zhou, X.

2006-01-01T23:59:59.000Z

206

Heat pipe heat amplifier  

SciTech Connect

In a heat pipe combination consisting of a common condenser section with evaporator sections at either end, two working fluids of different vapor pressures are employed to effectively form two heat pipe sections within the same cavity to support an amplifier mode of operation.

Arcella, F.G.

1978-08-15T23:59:59.000Z

207

Chemical heat pump  

DOE Patents (OSTI)

A chemical heat pump system is disclosed for use in heating and cooling structures such as residences or commercial buildings. The system is particularly adapted to utilizing solar energy, but also increases the efficiency of other forms of thermal energy when solar energy is not available. When solar energy is not available for relatively short periods of time, the heat storage capacity of the chemical heat pump is utilized to heat the structure as during nighttime hours. The design also permits home heating from solar energy when the sun is shining. The entire system may be conveniently rooftop located. In order to facilitate installation on existing structures, the absorber and vaporizer portions of the system may each be designed as flat, thin wall, thin pan vessels which materially increase the surface area available for heat transfer. In addition, this thin, flat configuration of the absorber and its thin walled (and therefore relatively flexible) construction permits substantial expansion and contraction of the absorber material during vaporization and absorption without generating voids which would interfere with heat transfer. The heat pump part of the system heats or cools a house or other structure through a combination of evaporation and absorption or, conversely, condensation and desorption, in a pair of containers. A set of automatic controls change the system for operation during winter and summer months and for daytime and nighttime operation to satisfactorily heat and cool a house during an entire year. The absorber chamber is subjected to solar heating during regeneration cycles and is covered by one or more layers of glass or other transparent material. Daytime home air used for heating the home is passed at appropriate flow rates between the absorber container and the first transparent cover layer in heat transfer relationship in a manner that greatly reduce eddies and resultant heat loss from the absorbant surface to ambient atmosphere.

Greiner, Leonard (2750-C Segerstrom Ave., Santa Ana, CA 92704)

1980-01-01T23:59:59.000Z

208

HYCSOS: a chemical heat pump and energy conversion system based on metal hydrides. 1979 status report  

DOE Green Energy (OSTI)

The current status of the HYCSOS chemical heat pump and energy conversion system based on metal hydrides is described. Heat transfer fluid loops were insulated and modified for isothermal operation. Software development for HYCSOS manual mode operation was completed. Routines to handle data acquisition, logging, compression, correction and plotting, using a Tektronix Graphics system with flexible disk data storage, provide a rapid and versatile means of presenting HYCSOS data for analysis. Advanced concept heat exchangers to improve the heat transfer of the hydride bed with the heat transfer fluid are discussed. Preliminary tests made with a LaNi/sub 5/ loaded aluminum foam test unit showed that heat transfer properties are very markedly improved. Thermodynamic expressions are applied to the selection of alloys for use in HYCSOS. The substitution of aluminum for nickel in AB/sub 5/ type alloys is shown to reduce hysteresis and permits the use of potentially lower cost materials with added flexibility for the optimization of engineering design and performance characteristics of the hydride heat pump system. Transient thermal measurements on hydride beds of CaNi/sub 5/ and LaNi/sub 5/ show no deterioration with cycling. Relatively slow heat transfer between the hydride beds and heat transfer fluid in the coiled tube heat exchangers is indicated by temperature lag of the bed and heat transfer fluid. Improved heat transfer is anticipated with aluminum foam heat exchangers.

Sheft, I.; Gruen, D.M.; Lamich, G.

1979-04-01T23:59:59.000Z

209

Rankine cycle machines for solar cooling  

DOE Green Energy (OSTI)

A vigorous effort to develop and demonstrate practical uses of solar energy to heat and cool buildings, to process agricultural products, and to provide thermal and electrical energy for industry has been initiated. One significant part of this effort is the research, development, and demonstration of Rankine cycle machines using fluids heated by solar energy. Recent developments in three such devices are discussed briefly.

Weathers, H.M.

1978-08-01T23:59:59.000Z

210

Radiant Heating  

Energy.gov (U.S. Department of Energy (DOE))

Radiant heating systems involve supplying heat directly to the floor or to panels in the walls or ceiling of a house. The systems depend largely on radiant heat transfer: the delivery of heat...

211

Stirling engine heating system  

SciTech Connect

A hot gas engine is described wherein a working gas flows back and forth in a closed path between a relatively cooler compression cylinder side of the engine and a relatively hotter expansion cylinder side of the engine and the path contains means including a heat source and a heat sink acting upon the gas in cooperation with the compression and expansion cylinders to cause the gas to execute a thermodynamic cycle wherein useful mechanical output power is developed by the engine, the improvement in the heat source which comprises a plurality of individual tubes each forming a portion of the closed path for the working gas.

Johansson, L.N.; Houtman, W.H.; Percival, W.H.

1988-06-28T23:59:59.000Z

212

High efficiency Brayton cycles using LNG  

DOE Patents (OSTI)

A modified, closed-loop Brayton cycle power conversion system that uses liquefied natural gas as the cold heat sink media. When combined with a helium gas cooled nuclear reactor, achievable efficiency can approach 68 76% (as compared to 35% for conventional steam cycle power cooled by air or water). A superheater heat exchanger can be used to exchange heat from a side-stream of hot helium gas split-off from the primary helium coolant loop to post-heat vaporized natural gas exiting from low and high-pressure coolers. The superheater raises the exit temperature of the natural gas to close to room temperature, which makes the gas more attractive to sell on the open market. An additional benefit is significantly reduced costs of a LNG revaporization plant, since the nuclear reactor provides the heat for vaporization instead of burning a portion of the LNG to provide the heat.

Morrow, Charles W. (Albuquerque, NM)

2006-04-18T23:59:59.000Z

213

Industrial and Commercial Heat Pump Applications in the United States  

E-Print Network (OSTI)

The energy crisis of 1973 accelerated the development of large-scale heat pumps in the United States. Since that time, the commercial, institutional, and industrial applications of heat pumps for waste heat recovery have expanded. This paper reviews the trends in heat pump cycle developments and discusses both the closed vapor compression cycle and refrigerants most commonly used and the open-cycle mechanical vapor compression heat pumps. Waste heat sources, heat loads served by heat pumps--and typical applications using heat pumps for large-scale space heating, domestic water heating, and industrial process water heating-- are discussed. Typical installations include commercial applications in hotels, high-rise apartments and condominiums, and office buildings. Institutional installations discussed include hospitals, universities, wastewater treatment plants, and airport terminals. Industrial applications largely center on food processing industries, feedwater heating, metal fabricating, and other industries. Reference is also made to other applications and alternative energy sources now gaining acceptance, including groundwater/geothermal water.

Niess, R. C.

1986-06-01T23:59:59.000Z

214

Enhanced absorption cycle computer model. Final report  

DOE Green Energy (OSTI)

Absorption heat pumps have received renewed and increasing attention in the past two decades. The rising cost of electricity has made the particular features of this heat-powered cycle attractive for both residential and industrial applications. Solar-powered absorption chillers, gas-fired domestic heat pumps, and waste-heat-powered industrial temperatures boosters are a few of the applications recently subjected to intensive research and development. The absorption heat pump research community has begun to search for both advanced cycles in various multistage configurations and new working fluid combinations with potential for enhanced performance and reliability. The development of working absorptions systems has created a need for reliable and effective system simulations. A computer code has been developed for simulation of absorption systems at steady state in a flexible and modular form, making it possible to investigate various cycle configurations with different working fluids. The code is based on unit subroutines containing the governing equations for the system`s components and property subroutines containing thermodynamic properties of the working fluids. The user conveys to the computer an image of his cycle by specifying the different subunits and their interconnections. Based on this information, the program calculates the temperature, flow rate, concentration, pressure, and vapor fraction at each state point in the system, and the heat duty at each unit, from which the coefficient of performance (COP) may be determined. This report describes the code and its operation, including improvements introduced into the present version. Simulation results are described for LiBr-H{sub 2}O triple-effect cycles, LiCl-H{sub 2}O solar-powered open absorption cycles, and NH{sub 3}-H{sub 2}O single-effect and generator-absorber heat exchange cycles. An appendix contains the User`s Manual.

Grossman, G.; Wilk, M. [Technion-Israel Inst. of Tech., Haifa (Israel). Faculty of Mechanical Engineering

1993-09-01T23:59:59.000Z

215

Absorption-heat-pump system  

DOE Patents (OSTI)

An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

Grossman, G.; Perez-Blanco, H.

1983-06-16T23:59:59.000Z

216

Nuclear Fuel Cycle Integrated System Analysis  

NLE Websites -- All DOE Office Websites (Extended Search)

Fuel Cycle Integrated System Analysis Fuel Cycle Integrated System Analysis Abdellatif M. Yacout Argonne National Laboratory Nuclear Engineering Division The nuclear fuel cycle is a complex system with multiple components and activities that are combined to provide nuclear energy to a variety of end users. The end uses of nuclear energy are diverse and include electricity, process heat, water desalination, district heating, and possibly future hydrogen production for transportation and energy storage uses. Components of the nuclear fuel cycle include front end components such as uranium mining, conversion and enrichment, fuel fabrication, and the reactor component. Back end of the fuel cycle include used fuel coming out the reactor, used fuel temporary and permanent storage, and fuel reprocessing. Combined with those components there

217

Advanced Open-Cycle Desiccant Cooling System  

E-Print Network (OSTI)

The concept of staged regeneration as means of improving the desiccant cooling system performance is the subject of investigation in this study. In the staged regeneration, the regeneration section of desiccant dehumidifier is divided into two parts and only the latter fraction is subjected to the desorption air stream which has been heated to the desired regeneration temperature. In the present work, the mathematical model describing the heat and mass transfer processes that occur during sorption of moisture in the desiccnnt dehumidifier includes both the gas-side (film) and solid-side resistances for heat and mass transports. The moisture diffusion in the desiccant material is expressed by gas-phase diffusion and surface diffusion. Effects of several parameters on the performance of desiccant cooling system with staged regeneration are investigated and the results of present model are compared with those of the lumped-resistance model. Results of this study show that coefficient of perfomnnce of the desiccant cooling system can be substantially improved by using the staged regeneration concept. There is an optimum stage fraction and optimum cycle time for given system parmeters and operating conditions. The results also indicate that the cooling system performance is higher than that predicted by the lumped-resistance model.

Ko, Y. J.; Charoensupaya, D.; Lavan, Z.

1989-01-01T23:59:59.000Z

218

Thermodynamic and economic analysis of cogeneration steam cycles  

SciTech Connect

Thermodynamic models for two district heating, cogeneration steam cycles were developed in this study. These cycles are an extraction-condensing turbine cycle and a back-pressure turbine cycle. Heat and electrical outputs of these cycles were calculated for inlet conditions ranging from 580 psi, 752 F, to 1740 psi, 995 F (4 MPa, 400/sup 0/C to 12 MPa, 535/sup 0/C), and district heat supply temperatures ranging from 194 F to 248 F (90/sup 0/C to 120/sup 0/C). Furthermore, the performance of these cycles from 0 to 100% of their maximum heat outputs were examined. A simple method of economic analysis based on annual costs was developed, which can take part-load operations into consideration. An extraction-condensing system and a back-pressure system were compared using this method.

Derbentli, T.; Kuehn, T.H.

1987-06-01T23:59:59.000Z

219

Low Level Heat Recovery Technology  

E-Print Network (OSTI)

With today's high fuel prices, energy conservation projects to utilize low level waste heat have become more attractive. Exxon Chemical Company Central Engineering has been developing guidelines and assessing the potential for application of low level heat recovery technology. This paper discusses heat distribution systems, latest developments in absorption refrigeration and organic Rankine cycles, and pressure, minimization possibilities. The relative merits and economics of the various possibilities and some guidelines on when they should be considered will be presented.

O'Brien, W. J.

1982-01-01T23:59:59.000Z

220

Maximum Fuel Energy Saving of a Brayton Cogeneration Cycle  

Science Conference Proceedings (OSTI)

An endoreversible Joule-Brayton cogeneration cycle has been optimized with fuel energy saving as an assessment criterion. The effects of power-to-heat ratio, cycle temperature ratio, and user temperature ratio on maximum fuel energy saving and efficiency ... Keywords: cogeneration cycle, fuel energy saving, thermodynamic optimization

Xiaoli Hao; Guoqiang Zhang

2009-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Effective material usage in a compact heat exchanger with periodic micro-channels / Bertus George Kleynhans.  

E-Print Network (OSTI)

??All modern High Temperature Reactors (HTR) thermal cycles have one thing in common: the use of some form of heat exchanger. This heat exchanger is… (more)

Kleynhans, Bertus George

2012-01-01T23:59:59.000Z

222

Heating Alloys  

Science Conference Proceedings (OSTI)

...are used in many varied applications--from small household appliances to large industrial process heating systems and furnaces. In appliances or industrial process heating, the heating elements are usually either open

223

The Carbon Cycle as the Main Determinant of Glacial-Interglacial Periods  

E-Print Network (OSTI)

An intriguing problem in climate science is the existence of Earth's glacial cycle. We show that it is possible to generate these periodic changes in climate by means of the Earth's carbon cycle as the main source factor. The carbon exchange between the Ocean, the Continent and the Atmosphere is modeled by means of a Lotka-Volterra three species system and the resulting atmospheric carbon cycle is used as the unique radiative forcing mechanism. It is shown that the carbon dioxide and temperature paths that are thus obtained have the same qualitative structure as the 100 kyr glacial-interglacial cycles depicted by the Vostok ice core data, reproducing the asymmetries of rapid heating--slow cooling, and short interglacial--long glacial ages.

de la Cuesta, Diego Jiménez; Núñez, Darío; Rumbos, Beatriz; Vergara-Cervantes, Carlos

2013-01-01T23:59:59.000Z

224

Parametric analysis of the Kalina cycle  

SciTech Connect

The Kalina cycle utilizes a mixture of ammonia and water as the working fluid in a vapor power cycle. When the liquid mixture is heated the more volatile ammonia tends to vaporize first and at a lower temperature tan does pure water. This property of ammonia-water mixtures makes possible a better match to the enthalpy-temperature curve of a hot gas heat source such as a gas turbine exhaust and also permits circulation of fluids of different composition in different parts of the cycle. Taking advantage of the latter feature, condensation (absorption) can be done at slightly above atmospheric pressure with a low concentration of ammonia, while heat input is at a higher concentration for optimum cycle performance. Computer models have been used to optimize a simplified form of the cycle and to compare results for a more complex version proposed by El-Sayed and Tribus. A method of balancing the cycle was developed and key parameters for optimizing the cycle identified.

Marston, C.H. (Villanova Univ., PA (USA). Dept. of Mechanical Engineering)

1990-01-01T23:59:59.000Z

225

Annual Cycle Energy System concept and application  

DOE Green Energy (OSTI)

The Annual Cycle Energy System (ACES), under development at ERDA's Oak Ridge National Laboratory, promises to provide space heating, air conditioning, and water heating at a significantly lower expenditure of energy than conventional space conditioning and water heating systems. The ACES embodies heat pumping, thermal storage and, where climate dictates, solar assistance. The concept is described, along with variations in design that permit flexibility to maximize energy conservation or to provide load management capabilities. Installations that exist or are under construction are described and variations that are incorporated to meet specific objectives are discussed.

Moyers, J. C.; Hise, E. C.

1977-01-01T23:59:59.000Z

226

Heating Systems  

Energy.gov (U.S. Department of Energy (DOE))

A variety of heating technologies are available today. In addition to heat pumps, which are discussed separately, many homes and buildings use the following approaches:

227

Feasibility of Thermoelectrics for Waste Heat Recovery in Conventional Vehicles  

SciTech Connect

Thermoelectric (TE) generators convert heat directly into electricity when a temperature gradient is applied across junctions of two dissimilar metals. The devices could increase the fuel economy of conventional vehicles by recapturing part of the waste heat from engine exhaust and generating electricity to power accessory loads. A simple vehicle and engine waste heat model showed that a Class 8 truck presents the least challenging requirements for TE system efficiency, mass, and cost; these trucks have a fairly high amount of exhaust waste heat, have low mass sensitivity, and travel many miles per year. These factors help maximize fuel savings and economic benefits. A driving/duty cycle analysis shows strong sensitivity of waste heat, and thus TE system electrical output, to vehicle speed and driving cycle. With a typical alternator, a TE system could allow electrification of 8%-15% of a Class 8 truck's accessories for 2%-3% fuel savings. More research should reduce system cost and improve economics.

Smith, K.; Thornton, M.

2009-04-01T23:59:59.000Z

228

AN ORGANIC MODERATED REACTOR FOR PROCESS HEAT  

SciTech Connect

A review is given of the potentialities of an organic moderated reactor for the supply of heat to factories having a large demand for low-pressure steam, together with a requirement for power produced by back-pressure turbine generation. By choosing a suitable steam cycle it is possible to cover the range of typical power demand/head load ratios found in the chemical industry. The economic developments of a reactor installed for such a duty are briefly considered to show the reductions in operating cost that might be brought about during the operating lifetlme of the reactor and its associated plant. (auth)

Baines, B.D.; Conway-Jones, J.M.

1962-02-01T23:59:59.000Z

229

Fuel Cell Power Model Elucidates Life-Cycle Costs for Fuel Cell-Based Combined Heat, Hydrogen, and Power (CHHP) Production Systems (Fact Sheet), Hydrogen and Fuel Cell Technical Highlights (HFCTH)  

NLE Websites -- All DOE Office Websites (Extended Search)

3 * November 2010 3 * November 2010 Electricity Natural Gas Power Heat Natural Gas or Biogas Tri-Generation Fuel Cell Hydrogen Natural Gas Converted to hydrogen on site via steam-methane reforming electrolyzer peak burner heat sink FC SYSTEM + H 2 Renewables H 2 -FC H 2 -storage 0 2 4 6 8 10 12 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Electricity Demand (kW) Heat Demand (kW) Hydrogen Demand (kW) 0 2 4 6 8 10 12 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Electricity Demand (kW) Heat Demand (kW) Hydrogen Demand (kW) 0 2 4 6 8 10 12 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Electricity Demand (kW) Heat Demand (kW) Hydrogen Demand (kW) 0 2 4 6 8 10 12 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Electricity Demand (kW) Heat Demand (kW) Hydrogen Demand (kW) * Grid electricity (hourly) * Fuel prices * Water price 0 2 4

230

Bubble Pump Design for Single Pressure Absorption Refrigeration Cycles  

E-Print Network (OSTI)

A model has been developed for the design and optimization of a small bubble pump to be used in a single pressure absorption refrigeration cycle to lift the working fluid mixture against gravity and overcome flow friction. This analytical model is developed from two-phase flow fundamentals and incorporates the design parameters of the bubble pump. Parametric studies are carried out and a design optimization for maximum efficiency is performed for various operating conditions. Optimum efficiency is defined as the liquid pumped per unit of bubble pump heat input. The results show the optimum bubble pump tube diameter over a range of operating conditions.

Sam V. Shelton; Susan White Stewart

2002-01-01T23:59:59.000Z

231

Heat Recovery Steam Generator Simulation  

E-Print Network (OSTI)

The paper discusses the applications of Heat Recovery Steam Generator Simulation. Consultants, plant engineers and plant developers can evaluate the steam side performance of HRSGs and arrive at the optimum system which matches the needs of the process plant, cogeneration or combined cycle plant. There is no need to design the HRSG per se and hence simulation is a valuable tool for anyone interested in evaluating the HRSG performance even before it is designed. It can also save a lot of time for specification writers as they need not guess how the steam side performance will vary with different gas/steam parameters. A few examples are given to show how simulation methods can be applied to real life problems.

Ganapathy, V.

1993-03-01T23:59:59.000Z

232

Thermal energy storage for an integrated coal gasification combined-cycle power plant  

DOE Green Energy (OSTI)

This study investigates the use of molten nitrate salt thermal energy storage in an integrated gasification combined-cycle power plant allowing the facility to economically provide peak- and intermediate-load electric power. The results of the study show that an integrated gasification combined-cycle power plant with thermal energy storage can reduce the cost of coal-fired peak- or intermediate-load electric power by between 5% and 20% depending on the plants operating schedule. The use of direct-contact salt heating can further improve the economic attractiveness of the concept. 11 refs., 1 fig., 4 tabs.

Drost, M.K.; Antoniak, Z.I.; Brown, D.R.

1990-03-01T23:59:59.000Z

233

Thermal energy storage for an integrated coal gasification combined-cycle power plant  

Science Conference Proceedings (OSTI)

This study investigates the use of molten nitrate salt thermal energy storage in an integrated gasification combined-cycle power plant allowing the facility to economically provide peak- and intermediate-load electric power. The results of the study show that an integrated gasification combined-cycle power plant with thermal energy storage can reduce the cost of coal-fired peak- or intermediate-load electric power by between 5% and 20% depending on the plants operating schedule. The use of direct-contact salt heating can further improve the economic attractiveness of the concept. 12 refs., 1 fig., 5 tabs.

Drost, K.; Antoniak, Z.; Brown, D.; Somasundaram, S.

1991-10-01T23:59:59.000Z

234

Binary Cycle Power Plant | Open Energy Information  

Open Energy Info (EERE)

GEOTHERMAL ENERGYGeothermal Home GEOTHERMAL ENERGYGeothermal Home Binary Cycle Power Plant General List of Binary Plants Binary power plant process diagram - DOE EERE 2012 Binary cycle geothermal power generation plants differ from Dry Steam and Flash Steam systems in that the water or steam from the geothermal reservoir never comes in contact with the turbine/generator units. Low to moderately heated (below 400°F) geothermal fluid and a secondary (hence, "binary") fluid with a much lower boiling point that water pass through a heat exchanger. Heat from the geothermal fluid causes the secondary fluid to flash to vapor, which then drives the turbines and subsequently, the generators. Binary cycle power plants are closed-loop systems and virtually nothing (except water vapor) is emitted to the atmosphere. Resources below 400°F

235

Cascading Closed Loop Cycle Power Generation  

E-Print Network (OSTI)

WOW Energies was issued Patent 6,857,268 B2 on Feb 22, 2005 titled “CASCADING CLOSED LOOP CYCLE (CCLC) and Patent 7,096,665 B2 on August 29, 2006 titled “CASCADING CLOSED LOOP CYCLE POWER GENERATION”. These patented technologies are collectively marketed as WOWGen®. The WOW Energies patents represent the production of efficient power from low, medium and high temperature heat generated from the combustion of fuels; heat from renewable energy sources such as solar and geothermal heat; or waste heat sources. Waste heat sources can be in the form of exhaust stack flue gases; waste heat from vented steam or steam discharged from steam turbines; hot water; hot oils or combined waste heat sources. A major advantage of the WOWGen® power plant is the ability to produce power without the use, consumption or contamination of valuable water resources. Production of power from waste heat and renewable energy sources is the most viable path to energy independence from foreign oil and reduced emissions from 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 facility. The presentation will focus on the technology and provide case studies of its application.

Romero, M.

2008-01-01T23:59:59.000Z

236

They`re he-e-re (almost): The 60% efficient combined cycle  

SciTech Connect

This article examines the technology that promises 60% efficiency from combined-cycle power plants. The topics of the article include advancing design, off-peak thermal energy storage, improving heat recovery steam generator performance, Kalina thermal cycle, performance of Kalina combined-cycle plants, and heat recovery in vapor generators.

DeMoss, T.B.

1996-07-01T23:59:59.000Z

237

Performance Optimization of an Irreversible Heat Pump with Variable-temperature Heat Reservoirs  

E-Print Network (OSTI)

An irreversible cycle model of a heat pump operating between two variable-temperature heat reservoirs is established and used to analyze the performance of the heat pump affected by heat resistances, heat leakage and internal dissipation of the working substance. The coefficient of performance of the heat pump is optimized for a given heating load. The characteristic curves of the coefficient of performance versus power input are generated. The influence of intake temperatures of heat reservoirs, thermal capacity of heat reservoirs, efficiency of heat exchangers, heat leak and internal irreversibilities on the performance of the system is discussed. The optimal ratio of the times spent on two processes of heat transfer to and from the working substance is determined. Some new results which are conducive to the optimal design and operation of real heat pump systems are obtained.

Huang, Y.; Sun, D.

2006-01-01T23:59:59.000Z

238

Functional groups show distinct differences in nitrogen cycling during early stand development: implications for forest management.  

SciTech Connect

Nutrient acquisition of forest stands is controlled by soil resource availability and belowground production, but tree species are rarely compared in this regard. Here, we examine ecological and management implications of nitrogen (N) dynamics during early forest stand development in productive commercial tree species with narrow (Populus deltoides Bartr. and Platanus occidentalis L.) and broad (Liquidambar styraciflua L. and Pinus taeda L.) site requirements while grown with a range of nutrient and water resources. We constructed N budgets by measuring N concentration ([N]) and N content (N{sub C}) of above- and belowground perennial and ephemeral tissues, determined N uptake (N{sub UP}), and calculated N use efficiency (NUE). Forest stands regulated [N] within species-specific operating ranges without clear temporal or treatment patterns, thus demonstrating equilibrium between tissue [N] and biomass accumulation. Forest stand N{sub C} and N{sub UP} increased with stand development and paralleled treatment patterns of biomass accumulation, suggesting productivity is tightly linked to N{sub UP}. Inclusion of above- and belowground ephemeral tissue turnover in N{sub UP} calculations demonstrated that maximum N demand for narrow-sites adapted species exceeded 200 kg N ha{sup -1} year{sup -1} while demand for broad-site adapted species was below this level. NUE was species dependent but not consistently influenced by N availability, suggesting relationships between NUE and resource availability were species dependent. Based on early stand development, species with broad site adaptability are favored for woody cropping systems because they maintain high above- and belowground productivity with minimal fertilization requirements due to higher NUE than narrow site adapted species.

Aubrey, Doug, P.; Coyle, David, R. Coleman, Mark, D.

2011-08-26T23:59:59.000Z

239

The evaporative gas turbine (EGT) cycle  

SciTech Connect

Humidification of the flow through a gas turbine has been proposed in a variety of forms. The STIG plant involves the generation of steam by the gas turbine exhaust in a heat recovery steam generator (HRSG), and its injection into or downstream of the combustion chamber. This increases the mass flow through the turbine and the power output from the plant, with a small increase in efficiency. In the evaporative gas turbine (or EGT) cycle, water is injected in the compressor discharge in a regenerative gas turbine cycle (a so-called CBTX plant--compressor [C], burner [B], turbine [T], heat exchanger [X]); the air is evaporatively cooled before it enters the heat exchanger. While the addition of water increases the turbine mass flow and power output, there is also apparent benefit in reducing the temperature drop in the exhaust stack. In one variation of the basic EGT cycle, water is also added downstream of the evaporative aftercooler, even continuously in the heat exchanger. There are several other variations on the basic cycle (e.g., the cascaded humidified advanced turbine [CHAT]). The present paper analyzes the performance of the EGT cycle. The basic thermodynamics are first discussed, and related to the cycle analysis of a dry regenerative gas turbine plant. Subsequently some detailed calculations of EGT cycles are presented. The main purpose of the work is to seek the optimum pressure ratio in the EGT cycle for given constraints (e.g., fixed maximum to minimum temperature). It is argued that this optimum has a relatively low value.

Horlock, J.H. [Whittle Lab., Cambridge (United Kingdom)

1998-04-01T23:59:59.000Z

240

Combined Cycle Performance Monitoring and Recovery Guideline  

Science Conference Proceedings (OSTI)

The benefits of improved combined cycle power plant performance continue to grow as the cost of fuel rises and international concerns over global warming increase.This guideline provides a framework for performance monitoring, assessment, recovery and optimization of combined cycle power plants. The guideline distills existing experience and documents on heat rate recovery and capacity improvement into a comprehensive manual for plant implementation and training applications. The purpose ...

2012-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Heat Exchanger Monitoring and Its Application to Cleaning and Antifoulant Use  

E-Print Network (OSTI)

Many refineries and chemical plants are presently experiencing considerable fuel savings and reduced maintenance costs as a result of their heat exchanger monitoring activities. Significant energy credits can be generated with proper applications of heat exchanger monitoring, the development of an optimum cleaning strategy and the use of antifoulants. This paper presents a brief overview of the heat exchanger monitoring procedure, and through examples, it shows the incentives of monitoring to measure base fouling, to determine optimum cleaning cycles, and to determine the effects of an antifoulant to control fouling.

Garcia, E.; Leach, S. H.; VanNostrand, W. L.

1983-01-01T23:59:59.000Z

242

ORCENT2. Nuclear Steam Turbine Cycle Analysis  

SciTech Connect

ORCENT2 performs heat and mass balance calculations at valves-wide-open design conditions, maximum guaranteed rating conditions, and an approximation of part-load conditions for steam turbine cycles supplied with throttle steam, characteristic of contemporary light-water reactors. The program handles both condensing and back-pressure turbine exhaust arrangements. Turbine performance calculations are based on the General Electric Company method for 1800-rpm large steam turbine-generators operating with light-water-cooled nuclear reactors. Output includes all information normally shown on a turbine-cycle heat balance diagram.

Fuller, L.C. [Oak Ridge National Lab, TN (United States)

1979-07-01T23:59:59.000Z

243

Show details for [Energy Storage III: Materials ...  

Science Conference Proceedings (OSTI)

Show details for [ACerS ACerS Arthur L. Friedberg Memorial Lecture. Show details for [ACerS ACerS Cooper Award ...

244

Heating Degree Day Data Applied to Residential Heating Energy Consumption  

Science Conference Proceedings (OSTI)

Site-specific total electric energy and heating oil consumption for individual residences show a very high correlation with National Weather Service airport temperature data when transformed to heating degree days. Correlations of regional total ...

Robert G. Quayle; Henry F. Diaz

1980-03-01T23:59:59.000Z

245

Heat transfer characteristics of a fluidized bed : stirling engine system.  

E-Print Network (OSTI)

??A fluidized bed combustion (FBC) system was designed to provide heat energy to the head of a Stirling cycle engine. Preliminary testing with a simulated… (more)

Anzalone, Thomas M.

1989-01-01T23:59:59.000Z

246

Heat Recovery from Aluminium Reduction Cells - Programmaster.org  

Science Conference Proceedings (OSTI)

The three main heat sources (cathode sides, anode yokes, and gas) were combined in different ways, using different types of power cycles. The potential for ...

247

Limit Cycle and Conserved Dynamics  

E-Print Network (OSTI)

We demonstrate that a potential coexists with limit cycle. Here the potential determines the final distribution of population. Our demonstration consists of three steps: We first show the existence of limit from a typical physical sciences setting: the potential is a type of Mexican hat type, with the strength of a magnetic field scale with the strength the potential gradient near the limit cycle, and the friction goes to zero faster than the potential near the limit cycle. Hence the dynamics at the limit cycle is conserved. The diffusion matrix is nevertheless finite at the limit cycle. Secondly, we construct the potential in the dynamics with limit cycle in a typical dynamical systems setting. Thirdly, we argue that such a construction can be carried out in a more general situation based on a method discovered by one of us. This method of dealing with stochastic differential equation is in general different from both Ito and Stratonovich calculus. Our result may be useful in many related applications, such as in the discussion of metastability of limit cycle and in the construction of Hopfield potential in the neural network computation.

X. -M. Zhu; L. Yin; P. Ao

2004-12-21T23:59:59.000Z

248

Simulation and Analysis for Applying the Double-Stage Coupled Heat Pump System in the Villa of Cold Area  

E-Print Network (OSTI)

The conventional heating mode is a one-way circulation in cold areas, which causes abatement in the reserves of energy source and increases environmental pollution. An ecological cycle heating system, an air-to-water + apartment water-to-water double-stage coupled heat pump system, is presented in this paper based on analyzing the characteristics of the villa district heating. Prediction and analysis of the feasibility of the double-stage coupled heat pump system in cold areas were carried after the components and characteristics of the system are introduced. The lumped parameter method was used to establish a mathematical model of the whole system, and the system control methods and the volume of the heat storage tank were decided to get the best value of the heating seasonal performance factor (HSPF). Furthermore, the application of the double-stage coupled heat pump system in some representative cities of cold areas in China was analyzed. The results show that the novel heat pump system can be used for heating the villa district in cold areas. To make the HSPF of the system much better, the water circulations of the double-stage coupled heat pump system also were analyzed in this paper; some improvements are put forward, and single-double stages mixed heat pumps system for the villa districts heating are introduced.

Yang, L.; Yao, Y.; Ma, Z.

2006-01-01T23:59:59.000Z

249

Wood Burning Combined Cycle Power Plant  

E-Print Network (OSTI)

A combined cycle power plant utilizing wood waste products as a fuel has been designed. This plant will yield a 50% efficiency improvement compared to conventional wood-fueled steam power plants. The power plant features an externally-fired gas turbine combined cycle system that obtains its heat input from a high temperature, high pressure ceramic air heater burning wood waste products as a fuel. This paper presents the results of the design study including the cycle evaluation and a description of the major components of the power plant. The cycle configuration is based on maximum fuel efficiency with minimum capital equipment risk. The cycle discussion includes design point performance of the power plant. The design represents a significant step forward in wood-fueled power plants.

Culley, J. W.; Bourgeois, H. S.

1984-01-01T23:59:59.000Z

250

Transposed critical temperature Rankine thermodynamic cycle  

DOE Green Energy (OSTI)

The transposed critical temperature (TPCT) is shown to be an extremely important thermodynamic property in the selection of the working fluid and turbine states for optimized geothermal power plants operating on a closed organic (binary) Rankine cycle. When the optimum working fluid composition and process states are determined for given source and sink conditions (7 parameter optimization), turbine inlet states are found to be consistently adjacent to the low pressure side of the working fluids' TPCT line on pressure-enthalpy coordinates. Although the TPCT concepts herein may find numerous future applications in high temperature, advanced cycles for fossil or nuclear fired steam power plants and in supercritical organic Rankine heat recovery bottoming cycles for Diesel engines, this discussion is limited to moderate temperature (150 to 250/sup 0/C) closed simple organic Rankine cycle geothermal power plants. Conceptual design calculations pertinent to the first geothermal binary cycle Demonstration Plant are included.

Pope, W.L.; Doyle, P.A.

1980-04-01T23:59:59.000Z

251

Life Cycle Engineering Group  

Science Conference Proceedings (OSTI)

... for green manufacturing and construction applications; conduct life cycle engineering assessments for energy efficiency and environmental ...

2012-08-23T23:59:59.000Z

252

Utility-scale combined-cycle power systems with Kalina bottoming cycles  

SciTech Connect

A new power-generation technology, often referred to as the Kalina cycle, is being developed as a direct replacement for the Rankine steam cycle. It can be applied to any thermal heat source, low or high temperature. Among several Kalina cycle variations, there is one that is particularly well suited as a bottoming cycle for utility combined-cycle applications. It is the subject of this paper. Using an ammonia/water mixture as the working fluid and a condensing system based on absorption-refrigeration principles, the Kalina bottoming cycle outperforms a triple-pressure steam cycle by 16%. Additionally, this version of the Kalina cycle is characterized by an intercooling feature between turbine stages, diametrically opposite to normal reheating practice in steam plants. Energy and mass balances are presented for a 200-MW(electric) Kalina bottoming cycle. Kalina cycle performance is compared to a triple-pressure steam plant. Energy and mass balances are presented as well for a 200-MW(electric) Kalina direct-fired cycle designed for utility purposes.

Kalina, A.I.

1987-01-01T23:59:59.000Z

253

Thermal Cycling Effects on the Thermoelectric Properties of n-Type In, Ce based Skutterudite Compounds  

SciTech Connect

N-type In-filled CoSb3 are known skutterudite compounds that have shown promising thermoelectric (TE) properties resulting in high dimensionless figure of merit values at elevated temperatures. Their use in various waste heat recovery applications will require that they survive and operate after exposure to harsh thermal cycling environments. This research focused on uncovering the thermal cycling effects on thermoelectric properties of n-type In0.2Co4Sb12 and In0.2Ce0.15Co4Sb12 skutterudite compositions as well as quantifying their temperature-dependent structural properties (elastic modulus, shear modulus, and Poisson's ratio). It was observed that the Seebeck coefficient and resistivity increased only slightly in the double-filled In,Ce skutterudite materials upon thermal cycling. In the In-filled skutterudites the Seebeck coefficient remained approximately the same on thermal cycling, while electrical resistivity increased significantly after thermal cycling. Results also show that thermal conductivity marginally decreases in the case of In-filled skutterudites, whereas the reduction is more pronounced in In, Ce-based skutterudite compounds. The possible reason for this kind of reduction can be attributed to grain pinning effects due to formation of nano inclusions. High temperature structural property measurements (i.e., Young's modulus and shear modulus) are also reported and the results show that these structural properties decrease slowly as temperature increases and the compounds are structurally stable after numerous thermal cycles.

Biswas, Krishnendu; Subramanian, Mas A.; Good, Morris S.; Roberts, Kamandi C.; Hendricks, Terry J.

2012-06-14T23:59:59.000Z

254

Inside Gun Shows What Goes On  

E-Print Network (OSTI)

Gun Shows Work Buying and Selling What's for Sale Culture Politics Interventions v 1 11 55 91 159 219Preface Inside Gun Shows What Goes On When Everybody Thinks Nobody's Watching #12;#12;Inside Gun-Violence Effort. She put gun shows on my radar and is an ace straw-purchase spotter. Thanks also to Barbara Claire

Leistikow, Bruce N.

255

Heat Conduction  

Science Conference Proceedings (OSTI)

Table 2   Differential equations for heat conduction in solids...conduction in solids General form with variable thermal properties General form with constant thermal properties General form, constant properties, without heat

256

Industrial heat pumps in Germany -potentials, technological development  

E-Print Network (OSTI)

jet nozzle Closed Cycles: Absorption/Adsorption heat pump thermal compressor driven by waste heat to 80 COP heating 2.5 to 5.8 Cooling function 50% of manufacturers offer cooling functions Cooling capacity [kW] 20 to 2500 COP cooling 1 to 6 #12;ACHEMA 2012 - Industrial heat pumps 21st June 2012

Oak Ridge National Laboratory

257

Development of the Household Sample for Furnace and Boiler Life-Cycle Cost  

NLE Websites -- All DOE Office Websites (Extended Search)

Development of the Household Sample for Furnace and Boiler Life-Cycle Cost Development of the Household Sample for Furnace and Boiler Life-Cycle Cost Analysis Title Development of the Household Sample for Furnace and Boiler Life-Cycle Cost Analysis Publication Type Report LBNL Report Number LBNL-55088 Year of Publication 2005 Authors Whitehead, Camilla Dunham, Victor H. Franco, Alexander B. Lekov, and James D. Lutz Document Number LBNL-55088 Pagination 22 Date Published May 31 Publisher Lawrence Berkeley National Laboratory City Berkeley Abstract Residential household space heating energy use comprises close to half of all residential energy consumption. Currently, average space heating use by household is 43.9 Mbtu for a year. An average, however, does not reflect regional variation in heating practices, energy costs, or fuel type. Indeed, a national average does not capture regional or consumer group cost impacts from changing efficiency levels of heating equipment. The US Department of Energy sets energy standards for residential appliances in, what is called, a rulemaking process. The residential furnace and boiler efficiency rulemaking process investigates the costs and benefits of possible updates to the current minimum efficiency regulations. Lawrence Berkeley National Laboratory (LBNL) selected the sample used in the residential furnace and boiler efficiency rulemaking from publically available data representing United States residences. The sample represents 107 million households in the country. The data sample provides the household energy consumption and energy price inputs to the life-cycle cost analysis segment of the furnace and boiler rulemaking. This paper describes the choice of criteria to select the sample of houses used in the rulemaking process. The process of data extraction is detailed in the appendices and is easily duplicated.The life-cycle cost is calculated in two ways with a household marginal energy price and a national average energy price. The LCC results show that using an national average energy price produces higher LCC savings but does not reflect regional differences in energy price.

258

The Paris Motor Show | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Paris Motor Show Paris Motor Show The Paris Motor Show October 4, 2010 - 9:39am Addthis David Sandalow at the Paris Auto Show | DOE photo David Sandalow at the Paris Auto Show | DOE photo David Sandalow David Sandalow Former Under Secretary of Energy (Acting) and Assistant Secretary for Policy & International Affairs At the Paris Motor Show today, electric cars are everywhere. Chevrolet is showing off the Volt, its plug-in hybrid due in U.S. showrooms this December. (Motown music blared as a Chevy rep told me all about the car's performance.) Nissan is displaying the Leaf, its all-electric sedan scheduled to roll off assembly lines in Tennessee starting in 2012. Volvo has new plug-in models. So do Saab, Peugot and other European manufacturers. And as I walked through the gates in a huge crowd, the first

259

The Paris Motor Show | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The Paris Motor Show The Paris Motor Show The Paris Motor Show October 4, 2010 - 9:39am Addthis David Sandalow at the Paris Auto Show | DOE photo David Sandalow at the Paris Auto Show | DOE photo David Sandalow David Sandalow Former Under Secretary of Energy (Acting) and Assistant Secretary for Policy & International Affairs At the Paris Motor Show today, electric cars are everywhere. Chevrolet is showing off the Volt, its plug-in hybrid due in U.S. showrooms this December. (Motown music blared as a Chevy rep told me all about the car's performance.) Nissan is displaying the Leaf, its all-electric sedan scheduled to roll off assembly lines in Tennessee starting in 2012. Volvo has new plug-in models. So do Saab, Peugot and other European manufacturers. And as I walked through the gates in a huge crowd, the first

260

Heat exchanger  

DOE Patents (OSTI)

A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

Daman, Ernest L. (Westfield, NJ); McCallister, Robert A. (Mountain Lakes, NJ)

1979-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Retrieval of Latent Heating from TRMM Measurements  

Science Conference Proceedings (OSTI)

Rainfall is a fundamental process within the Earth's hydrological cycle because it represents a principal forcing term in surface water budgets, while its energetics corollary, latent heating, is the principal source of atmospheric diabatic ...

W-K. Tao; E. A. Smith; R. F. Adler; A. Y. Hou; R. Meneghini; J. Simpson; Z. S. Haddad; T. Iguchi; S. Satoh; R. Kakar; T. N. Krishnamurti; C. D. Kummerow; S. Lang; K. Nakamura; T. Nakazawa; K. Okamoto; S. Shige; W. S. Olson; Y. Takayabu; G. J. Tripoli; S. Yang

2006-11-01T23:59:59.000Z

262

Diabatic Heating Profiles in Recent Global Reanalyses  

Science Conference Proceedings (OSTI)

Diabatic heating profiles are extremely important to the atmospheric circulation in the tropics and therefore to the earth’s energy and hydrological cycles. However, their global structures are poorly known because of limited information from in ...

Jian Ling; Chidong Zhang

2013-05-01T23:59:59.000Z

263

Detroit Auto Show 2012 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Management Trade Show Supercomputers' Pictorial Superpowers How the Smart Grid Helps Homeowners Reduce Their Energy Use EcoCAR Challenge Finish Line Event 1 of 8 Students Earn...

264

Laser research shows promise for cancer treatment  

NLE Websites -- All DOE Office Websites (Extended Search)

treatment Laser research shows promise for cancer treatment Scientists have observed for the first time how a laser penetrates dense, electron-rich plasma to generate ions. August...

265

Combined cycle power plant incorporating coal gasification  

DOE Patents (OSTI)

A combined cycle power plant incorporating a coal gasifier as the energy source. The gases leaving the coal gasifier pass through a liquid couplant heat exchanger before being used to drive a gas turbine. The exhaust gases of the gas turbine are used to generate both high pressure and low pressure steam for driving a steam turbine, before being exhausted to the atmosphere.

Liljedahl, Gregory N. (Tariffville, CT); Moffat, Bruce K. (Simsbury, CT)

1981-01-01T23:59:59.000Z

266

A Kalina cycle technology and its applications  

SciTech Connect

A thermodynamic cycle with variation in the composition of the working fluid used in the process has been developed. The additional degree of freedom of design due to the variation in the composition of the working fluid provides superior efficiency for several diversified applications such as industrial waste-heat recovery, geothermal, fuel-fired power plants, and others.

Kalina, A.I.

1986-01-01T23:59:59.000Z

267

Validation of a PC based program for single stage absorption heat pump. Final report  

Science Conference Proceedings (OSTI)

An interactive computer code was developed to evaluate single stage absorption heat pump performance for temperature amplifier and heat amplifier modes using water as the refrigerant. This program performs the cycle calculations for single stage cycles based on the polynomial expressions developed to correlate experimental vapor-liquid-equilibrium (VLE) and specific enthalpy-concentration data for LiBr/water and (Li, K, Na)NO{sub 3}/water systems as well as the properties of pure water. The operating parameters obtained by this program were tested against mass and energy balances in documented cases and the results show that the maximum deviation between coefficient of performance (COP) values obtained by this software and the ones previously calculated is less than 3%. In addition, this program was used to study the effect of solution temperature leaving the absorber on the other operating parameters. This type of analysis could be used to improve and optimize cycle design. 4 refs.

Zaltash, A.; Ally, M.R.

1991-09-01T23:59:59.000Z

268

Validation of a PC based program for single stage absorption heat pump  

SciTech Connect

An interactive computer code was developed to evaluate single stage absorption heat pump performance for temperature amplifier and heat amplifier modes using water as the refrigerant. This program performs the cycle calculations for single stage cycles based on the polynomial expressions developed to correlate experimental vapor-liquid-equilibrium (VLE) and specific enthalpy-concentration data for LiBr/water and (Li, K, Na)NO{sub 3}/water systems as well as the properties of pure water. The operating parameters obtained by this program were tested against mass and energy balances in documented cases and the results show that the maximum deviation between coefficient of performance (COP) values obtained by this software and the ones previously calculated is less than 3%. In addition, this program was used to study the effect of solution temperature leaving the absorber on the other operating parameters. This type of analysis could be used to improve and optimize cycle design. 4 refs.

Zaltash, A.; Ally, M.R.

1991-09-01T23:59:59.000Z

269

Evolution Dynamics of Tropical Ocean-Atmosphere Annual Cycle Variability  

Science Conference Proceedings (OSTI)

The structure of ocean-atmosphere annual cycle variability is extracted from the revised Comprehensive Ocean-Atmosphere Data Set SSTs, surface winds, and the latent heat (LH) and net shortwave (SW) surface fluxes using the covariance-based ...

Sumant Nigam; Yi Chao

1996-12-01T23:59:59.000Z

270

Microsoft PowerPoint - Application of Stirling Cycle Generators...  

NLE Websites -- All DOE Office Websites (Extended Search)

VDC Pumping 24 VDC 460 A-Hr Battery Bank 24 VDC To 3 208 VAC Pumping Unit 24 208 y Inverter 24VDC VDC 208 VAC Stirling Cycle Heated Fuel Gas Umbilical 24VDC Rod Work Well...

271

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-Print Network (OSTI)

of low-grade heat," Renewable and Sustainable Energyof various applications," Renewable and Sustainable Energyorganic Rankine cycle," Renewable Energy, vol. 4, pp. 1196-

Ho, Tony

2012-01-01T23:59:59.000Z

272

A statistical analysis of avalanching heat transport in stationary enhanced core confinement regimes  

Science Conference Proceedings (OSTI)

We present a statistical analysis of heat transport in stationary enhanced confinement regimes obtained from flux-driven gyrofluid simulations. The probability density functions of heat flux in improved confinement regimes, characterized by the Nusselt number, show significant deviation from Gaussian, with a markedly fat tail, implying the existence of heat avalanches. Two types of avalanching transport are found to be relevant to stationary states, depending on the degree of turbulence suppression. In the weakly suppressed regime, heat avalanches occur in the form of quasi-periodic (QP) heat pulses. Collisional relaxation of zonal flow is likely to be the origin of these QP heat pulses. This phenomenon is similar to transient limit cycle oscillations observed prior to edge pedestal formation in recent experiments. On the other hand, a spectral analysis of heat flux in the strongly suppressed regime shows the emergence of a 1/f (f is the frequency) band, suggesting the presence of self-organized criticality (SOC)-like episodic heat avalanches. This episodic 1/f heat avalanches have a long temporal correlation and constitute the dominant transport process in this regime.

Tokunaga, S.; Jhang, Hogun; Kim, S. S. [WCI Center for Fusion Theory, National Fusion Research Institute, 52, Yeoeun-dong, Yusung-Gu, Daejon (Korea, Republic of); Diamond, P. H. [WCI Center for Fusion Theory, National Fusion Research Institute, 52, Yeoeun-dong, Yusung-Gu, Daejon (Korea, Republic of); Center for Astrophysics and Space Sciences and Department of Physics, University of California San Diego, La Jolla, California 92093-0429 (United States)

2012-09-15T23:59:59.000Z

273

Inside Gun Shows What Goes On  

E-Print Network (OSTI)

as 40% of all gun sales. They are quick and convenient, and their anonymity will attract those who putInside Gun Shows What Goes On When Everybody Thinks Nobody's Watching Executive Summary #12;Inside Gun Shows What Goes on When Everybody Thinks Nobody's Watching Garen Wintemute, MD, MPH Violence

Nguyen, Danh

274

Experimental Research on Solar Assisted Heat Pump Heating System with Latent Heat Storage  

E-Print Network (OSTI)

Based on the status quo that conventional energy sources are more and more reduced and environmental pollution is increasingly serious, this paper presents a new model system of conserving energy and environmental protection, namely, a Solar Assisted Heat Pump Heating System with Latent Heat Storage. In this system, solar energy is the major heat source for a heat pump, and the supplementary heat source is soil. The disagreement in time between the space heat load and heat collected by solar heat collector is solved by latent heat storage. In order to obtain such system running conditions and effects in different heating periods, an experiment has been carried out during the whole heating period in Harbin, China. The experimental results show that this system is much better for heating in initial and late periods than that in middle periods. The average heating coefficient is 6.13 for heating in initial and late periods and 2.94 for heating in middle periods. At the same time, this paper also predicts system running properties in other regions.

Han, Z.; Zheng, M.; Liu, W.; Wang, F.

2006-01-01T23:59:59.000Z

275

Susanville District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

Susanville District Heating District Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Susanville District Heating District Heating Low Temperature...

276

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 222 194 17...

277

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings ... 2,100...

278

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,928 1,316...

279

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All...

280

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,870 1,276...

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings* ... 1,602 1,397...

282

Total Space Heating Water Heating Cook-  

Gasoline and Diesel Fuel Update (EIA)

Released: September, 2008 Total Space Heating Water Heating Cook- ing Other Total Space Heating Water Heating Cook- ing Other All Buildings ... 2,037...

283

Westinghouse fuel cell combined cycle systems  

DOE Green Energy (OSTI)

Efficiency (voltage) of the solid oxide fuel cell (SOFC) should increase with operating pressure, and a pressurized SOFC could function as the heat addition process in a Brayton cycle gas turbine (GT) engine. An overall cycle efficiency of 70% should be possible. In cogeneration, half of the waste heat from a PSOFC/GT should be able to be captured in process steam and hot water, leading to a fuel effectiveness of about 85%. In order to make the PSOFC/GT a commercial reality, satisfactory operation of the SOFC at elevated pressure must be verified, a pressurized SOFC generator module must be designed, built, and tested, and the combined cycle and parameters must be optimized. A prototype must also be demonstrated. This paper describes progress toward making the PSOFC/GT a reality.

Veyo, S.

1996-12-31T23:59:59.000Z

284

Nuclear Fuel Cycle | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Cycle Cycle Nuclear Fuel Cycle This is an illustration of a nuclear fuel cycle that shows the required steps to process natural uranium from ore for preparation for fuel to be loaded in nuclear reactors. This is an illustration of a nuclear fuel cycle that shows the required steps to process natural uranium from ore for preparation for fuel to be loaded in nuclear reactors. The mission of NE-54 is primarily focused on activities related to the front end of the nuclear fuel cycle which includes mining, milling, conversion, and enrichment. Uranium Mining Both "conventional" open pit, underground mining, and in situ techniques are used to recover uranium ore. In general, open pit mining is used where deposits are close to the surface and underground mining is used

285

SunShot Initiative: Brayton Cycle Baseload Power Tower  

NLE Websites -- All DOE Office Websites (Extended Search)

Brayton Cycle Baseload Power Brayton Cycle Baseload Power Tower to someone by E-mail Share SunShot Initiative: Brayton Cycle Baseload Power Tower on Facebook Tweet about SunShot Initiative: Brayton Cycle Baseload Power Tower on Twitter Bookmark SunShot Initiative: Brayton Cycle Baseload Power Tower on Google Bookmark SunShot Initiative: Brayton Cycle Baseload Power Tower on Delicious Rank SunShot Initiative: Brayton Cycle Baseload Power Tower on Digg Find More places to share SunShot Initiative: Brayton Cycle Baseload Power Tower on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act Baseload CSP SunShot Multidisciplinary University Research Initiative CSP Heat Integration for Baseload Renewable Energy Deployment

286

Supercritical CO2 direct cycle Gas Fast Reactor (SC-GFR) concept.  

SciTech Connect

This report describes the supercritical carbon dioxide (S-CO{sub 2}) direct cycle gas fast reactor (SC-GFR) concept. The SC-GFR reactor concept was developed to determine the feasibility of a right size reactor (RSR) type concept using S-CO{sub 2} as the working fluid in a direct cycle fast reactor. Scoping analyses were performed for a 200 to 400 MWth reactor and an S-CO{sub 2} Brayton cycle. Although a significant amount of work is still required, this type of reactor concept maintains some potentially significant advantages over ideal gas-cooled systems and liquid metal-cooled systems. The analyses presented in this report show that a relatively small long-life reactor core could be developed that maintains decay heat removal by natural circulation. The concept is based largely on the Advanced Gas Reactor (AGR) commercial power plants operated in the United Kingdom and other GFR concepts.

Wright, Steven Alan; Parma, Edward J., Jr.; Suo-Anttila, Ahti Jorma (Computational Engineering Analysis, Albuquerque, NM); Al Rashdan, Ahmad (Texas A& M University, College Station, TX); Tsvetkov, Pavel Valeryevich (Texas A& M University, College Station, TX); Vernon, Milton E.; Fleming, Darryn D.; Rochau, Gary Eugene

2011-05-01T23:59:59.000Z

287

International Builders' Show | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Builders' Show Builders' Show International Builders' Show February 14, 2008 - 11:29am Addthis Remarks as Prepared for Delivery by Secretary Bodman Thank you, Andy, and thank you all for being here. The world has reached an energy crossroads. Rising global energy demand and the need for more environmentally-responsible energy production and consumption have presented us with a number of global challenges that require global solutions. Every American has a role to play in meeting these challenges. And that's why I am very pleased to be here at the International Builders' Show, to tour the floor and to see the technologies that are penetrating the marketplace - many of which originated in DOE's network of world-class national laboratories. I also pleased to be here with the National Association of Home Builders

288

2013 Washington Auto Show | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

2013 Washington Auto Show 2013 Washington Auto Show 2013 Washington Auto Show Addthis 1 of 10 While at the Washington Auto Show, Energy Secretary Steven Chu visited Nissan to see the 2013 Leaf. | Photo courtesy of Sarah Gerrity, Energy Department. Date taken: 2013-01-31 13:50 2 of 10 The new Nissan Leaf is being built at the company's Smyrna, Tennessee, Vehicle Assembly Plant -- helping to cut the price of its electric vehicle. | Photo courtesy of Sarah Gerrity, Energy Department. Date taken: 2013-01-31 13:49 3 of 10 Energy Secretary Steven Chu discusses the features of the 2014 Cadillac ELR -- the luxury car built built on the same powertrain platform as the Chevy Volt. | Photo courtesy of Sarah Gerrity, Energy Department. Date taken: 2013-01-31 13:57 4 of 10 Energy Secretary Steven Chu discusses some of the features of the Chevy

289

Detroit Auto Show 2012 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

What&039;s your energypledge? What's your EnergyPledge? 1. Secretary Chu at the Detroit Auto Show Snapshots of the Year in Energy: 12 Awesome Photos from 2012 Day 12: Drive...

290

Gasoline price shows small increase (long version)  

Annual Energy Outlook 2012 (EIA)

long version) The U.S. average retail price for regular gasoline showed little movement from last week. Prices rose 410 of a cent to 3.30 a gallon on Monday, based on the weekly...

291

Gasoline price shows small increase (short version)  

U.S. Energy Information Administration (EIA) Indexed Site

showed little movement from last week. Prices rose 410 of a cent to 3.30 a gallon on Monday, based on the weekly price survey by the U.S. Energy Information Administration....

292

Field measurement of the interactions between heat pumps and attic duct systems in residential buildings  

SciTech Connect

Research efforts to improve residential heat-pump performance have tended to focus on laboratory and theoretical studies of the machine itself, with some limited field research having been focused on in-situ performance and installation issues. One issue that has received surprisingly little attention is the interaction between the heat pump and the duct system to which it is connected. This paper presents the results of a field study that addresses this interaction. Field performance measurements before and after sealing and insulating the duct systems were made on three heat pumps. From the pre-retrofit data it was found that reductions in heat-pump capacity due to low outdoor temperatures and/or coil frosting are accompanied by lower duct-system energy delivery efficiencies. The conduction loss reductions, and thus the delivery temperature improvements, due to adding duct insulation were found to vary widely depending on the length of the particular duct section, the thermal mass of that duct section, and the cycling characteristics of the heat-pump. In addition, it was found that the use of strip-heat back-up decreased after the retrofits, and that heat-pump cycling increased dramatically after the retrofits, which respectively increase and decrease savings due to the retrofits. Finally, normalized energy use for the three systems which were operated consistently pre- and post-retrofit showed an average reduction of 19% after retrofit, which corresponds to a chance in overall distribution-system efficiency of 24%.

Modera, M.P.; Jump, D.A. [Lawrence Berkeley Lab., CA (United States). Energy and Environment Div.

1994-11-01T23:59:59.000Z

293

Quantifying Carbon Cycle Feedbacks  

Science Conference Proceedings (OSTI)

Perturbations to the carbon cycle could constitute large feedbacks on future changes in atmospheric CO2 concentration and climate. This paper demonstrates how carbon cycle feedback can be expressed in formally similar ways to climate feedback, ...

J. M. Gregory; C. D. Jones; P. Cadule; P. Friedlingstein

2009-10-01T23:59:59.000Z

294

Edgeworth cycles revisited  

E-Print Network (OSTI)

Some gasoline markets exhibit remarkable price cycles, where price spikes are followed by a series of small price declines: a pattern consistent with a model of Edgeworth cycles described by Maskin and Tirole. We extend ...

Doyle, Joseph J.

295

Proceedings: Sixth International Conference on Fossil Plant Cycle Chemistry  

Science Conference Proceedings (OSTI)

The purity of boiler water, feedwater, and steam is central to ensuring component availability and reliability in fossil-fired plants. These conference proceedings address the state of the art in fossil plant and combined cycle/heat recovery steam generator (HRSG) cycle chemistry as well as international practices for control of corrosion and water preparation and purification.

None

2001-04-01T23:59:59.000Z

296

Proceedings: Sixth International Conference on Fossil Plant Cycle Chemistry  

Science Conference Proceedings (OSTI)

The purity of boiler water, feedwater, and steam is central to ensuring component availability and reliability in fossil-fired plants. These conference proceedings address the state of the art in fossil plant and combined cycle/heat recovery steam generator (HRSG) cycle chemistry as well as international practices for control of corrosion and water preparation and purification.

2001-03-30T23:59:59.000Z

297

Industrial Heat Pump Case Study  

E-Print Network (OSTI)

An open-cycle heat pump was retrofitted to a single-effect, recirculating-type evaporator used for reducing the water content of whey (a liquid by-product from cheese production). The purpose of the retrofit was to reduce the energy costs associated with operating the evaporator. The open-cycle heat pump design uses an electrically driven centrifugal compressor to recover the latent heat of the water vapor generated by the evaporator. (Steam was the original heat source but is now only needed for start-up.) This concept is sometimes called mechanical vapor compression (MVC) or mechanical vapor recompression (MVR). A variety of engineering issues have to be resolved to integrate a heat pump into an evaporator system. This paper identifies key issues and describes how they were resolved for this particular process. Issues include choice of compressor, motor selection, control strategy, impact of heat pump on heat exchanger surface area requirements and related issues, and methods for protecting the compressor from surge, droplet ingestion, and other hazards.

Wagner, J. R.; Brush, F. C.

1985-05-01T23:59:59.000Z

298

Consumer Electronics Show 2013 Highlights Sustainable Energy Technology |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Consumer Electronics Show 2013 Highlights Sustainable Energy Consumer Electronics Show 2013 Highlights Sustainable Energy Technology Consumer Electronics Show 2013 Highlights Sustainable Energy Technology January 18, 2013 - 4:52pm Addthis Excited attendees flood into the Central Hall exhibits to see the latest and greatest in technology at the 2013 International CES. | 2013 International CES Excited attendees flood into the Central Hall exhibits to see the latest and greatest in technology at the 2013 International CES. | 2013 International CES Erik Hyrkas Erik Hyrkas Media Relations Specialist, Office of Energy Efficiency & Renewable Energy What does this mean for me? Watch for the new sustainable technologies displayed at CES this year. Energy savings aren't all about efficient heating and cooling these days.

299

Consumer Electronics Show 2013 Highlights Sustainable Energy Technology |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Consumer Electronics Show 2013 Highlights Sustainable Energy Consumer Electronics Show 2013 Highlights Sustainable Energy Technology Consumer Electronics Show 2013 Highlights Sustainable Energy Technology January 18, 2013 - 4:52pm Addthis Excited attendees flood into the Central Hall exhibits to see the latest and greatest in technology at the 2013 International CES. | 2013 International CES Excited attendees flood into the Central Hall exhibits to see the latest and greatest in technology at the 2013 International CES. | 2013 International CES Erik Hyrkas Erik Hyrkas Media Relations Specialist, Office of Energy Efficiency & Renewable Energy What does this mean for me? Watch for the new sustainable technologies displayed at CES this year. Energy savings aren't all about efficient heating and cooling these days.

300

Energy Consumption and Demand as Affected by Heat Pumps that Cool, Heat and Heat Domestic Water  

E-Print Network (OSTI)

Products or systems that heat, cool and heat domestic water, which are also referred to as integrated systems, have been available for several years. The concept is simple and appeals to consumers. This paper presents methods for evaluating the potential savings by using an integrated system that heats water by desuperheating discharge gas in the refrigeration cycle. The methods may be applied for any specific location, and their accuracy will depend on the accuracy of building loads and water usage estimates. Power demand can also be affected by electric water heaters. The methods presented demonstrate how integrated systems can be of value in reducing daily summertime peaks.

Cawley, R.

1992-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Ã…-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

302

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Ã…-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

303

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Ã…-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

304

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Ã…-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

305

Hybrid solar central receiver for combined cycle power plant  

DOE Patents (OSTI)

A hybrid combined cycle power plant is described including a solar central receiver for receiving solar radiation and converting it to thermal energy. The power plant includes a molten salt heat transfer medium for transferring the thermal energy to an air heater. The air heater uses the thermal energy to preheat the air from the compressor of the gas cycle. The exhaust gases from the gas cycle are directed to a steam turbine for additional energy production. 1 figure.

Bharathan, D.; Bohn, M.S.; Williams, T.A.

1995-05-23T23:59:59.000Z

306

Advanced Control Demonstration on a Combined Cycle Plant  

Science Conference Proceedings (OSTI)

Southern Company, Electricit de France (EDF), and EPRI have undertaken a project to demonstrate the applicability of advanced control techniques on a combined-cycle heat recovery steam generator (HRSG). This report describes progress on the project during 2005 including model identification, the advanced controller design, controller program development, and controller testing in a simulation environment. A combined-cycle plant was selected as the host plant because many combined-cycle plants have chang...

2006-03-31T23:59:59.000Z

307

Hybrid solar central receiver for combined cycle power plant  

DOE Patents (OSTI)

A hybrid combined cycle power plant including a solar central receiver for receiving solar radiation and converting it to thermal energy. The power plant includes a molten salt heat transfer medium for transferring the thermal energy to an air heater. The air heater uses the thermal energy to preheat the air from the compressor of the gas cycle. The exhaust gases from the gas cycle are directed to a steam turbine for additional energy production.

Bharathan, Desikan (Lakewood, CO); Bohn, Mark S. (Golden, CO); Williams, Thomas A. (Arvada, CO)

1995-01-01T23:59:59.000Z

308

Show Me Ethanol LLC | Open Energy Information  

Open Energy Info (EERE)

Show Me Ethanol LLC Show Me Ethanol LLC Jump to: navigation, search Name Show Me Ethanol, LLC Place Carrollton, Missouri Zip 64633 Product Developing an ethanol project in Carrollton, Missouri. Coordinates 36.935443°, -76.531593° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":36.935443,"lon":-76.531593,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

309

Detroit Auto Show 2012 | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Detroit Auto Show 2012 Detroit Auto Show 2012 Detroit Auto Show 2012 Addthis 1 of 10 Energy Secretary Steven Chu with Chrysler Chief Executive Sergio Marchionne. Image: Hantz Leger (Energy Department Contractor) Date taken: 2012-01-10 00:00 2 of 10 Energy Secretary Steven Chu examines the Dodge Dart's four cylinder, 2.4-liter, 184 horsepower engine block. Image: Hantz Leger (Energy Department Contractor) Date taken: 2012-01-10 00:00 3 of 10 Energy Secretary Steven Chu gets behind the wheel of the new 2013 Dodge Dart. Image: Hantz Leger (Energy Department Contractor) Date taken: 2012-01-10 00:00 4 of 10 Energy Secretary Steven Chu examines the interior of the new 2013 Dodge Dart. Image: Hantz Leger (Energy Department Contractor) Date taken: 2012-01-10 00:00 5 of 10 Energy Secretary Steven Chu discusses the latest auto innovations with a

310

Cycle to Cycle Manufacturing Process Control  

E-Print Network (OSTI)

Most manufacturing processes produce parts that can only be correctly measured after the process cycle has been completed. Even if in-process measurement and control is possible, it is often too expensive or complex to ...

Hardt, David E.

311

Stability analysis of heat exchanger dynamics  

Science Conference Proceedings (OSTI)

In the study of vapor compression cycle, momentum balance equation is often ignored in the heat exchanger model. In this paper, we investigate the effect of the momentum balance through a systematic study of the open loop stability of a heat exchanger. ...

Tiejun Zhang; John T. Wen; Juan Catano; Rongliang Zhou

2009-06-01T23:59:59.000Z

312

Simulation and performance analysis of basic GAX and advanced GAX cycles with ammonia/water and ammonia/water/LiBr absorption fluids  

Science Conference Proceedings (OSTI)

The generator-absorber heat exchange (GAX) and branched GAX cycles are generally considered with NH{sub 3}/H{sub 2}O as their working fluid. The potential consequences of using a ternary mixture of NH{sub 3}/H{sub 2}O/LiBr (advanced fluids) in the GAX and Branched GAX (advanced cycles) are discussed in this study. A modular steady state absorption simulation model(ABSIM) was used to investigate the potential of combining the above advanced cycles with the advanced fluids. ABSIM is capable of modeling varying cycle configurations with different working fluids. Performance parameters of the cycles, including coefficient of performance (COP) and heat duties, were investigated as functions of different operating parameters in the cooling mode for both the NH {sub 3}/H{sub 2}O binary and the NH{sub 3}/H{sub 2}O/LiBr ternary mixtures. High performance potential of GAX and branched GAX cycles using the NH{sub 3}/H{sub 2}O/LiBr ternary fluid mixture was achieved especially at the high range of firing temperatures exceeding 400{degrees}F. The cooling COP`s have been improved by approximately 21% over the COP achieved with the NH{sub 3}/H{sub 2}O binary mixtures. These results show the potential of using advanced cycles with advanced fluid mixtures (ternary or quaternary fluid mixtures).

Zaltash, A.; Grossman, G.

1996-03-01T23:59:59.000Z

313

Pipeline bottoming cycle study. Final report  

Science Conference Proceedings (OSTI)

The technical and economic feasibility of applying bottoming cycles to the prime movers that drive the compressors of natural gas pipelines was studied. These bottoming cycles convert some of the waste heat from the exhaust gas of the prime movers into shaft power and conserve gas. Three typical compressor station sites were selected, each on a different pipeline. Although the prime movers were different, they were similar enough in exhaust gas flow rate and temperature that a single bottoming cycle system could be designed, with some modifications, for all three sites. Preliminary design included selection of the bottoming cycle working fluid, optimization of the cycle, and design of the components, such as turbine, vapor generator and condensers. Installation drawings were made and hardware and installation costs were estimated. The results of the economic assessment of retrofitting bottoming cycle systems on the three selected sites indicated that profitability was strongly dependent upon the site-specific installation costs, how the energy was used and the yearly utilization of the apparatus. The study indicated that the bottoming cycles are a competitive investment alternative for certain applications for the pipeline industry. Bottoming cycles are technically feasible. It was concluded that proper design and operating practices would reduce the environmental and safety hazards to acceptable levels. The amount of gas that could be saved through the year 2000 by the adoption of bottoming cycles for two different supply projections was estimated as from 0.296 trillion ft/sup 3/ for a low supply projection to 0.734 trillion ft/sup 3/ for a high supply projection. The potential market for bottoming cycle equipment for the two supply projections varied from 170 to 500 units of varying size. Finally, a demonstration program plan was developed.

Not Available

1980-06-01T23:59:59.000Z

314

Heat Stroke  

NLE Websites -- All DOE Office Websites (Extended Search)

stress, from exertion or hot environments, places stress, from exertion or hot environments, places workers at risk for illnesses such as heat stroke, heat exhaustion, or heat cramps. Heat Stroke A condition that occurs when the body becomes unable to control its temperature, and can cause death or permanent disability. Symptoms â–  High body temperature â–  Confusion â–  Loss of coordination â–  Hot, dry skin or profuse sweating â–  Throbbing headache â–  Seizures, coma First Aid â–  Request immediate medical assistance. â–  Move the worker to a cool, shaded area. â–  Remove excess clothing and apply cool water to their body. Heat Exhaustion The body's response to an excessive loss of water and salt, usually through sweating. Symptoms â–  Rapid heart beat â–  Heavy sweating â–  Extreme weakness or fatigue â– 

315

Heat reclaimer  

Science Conference Proceedings (OSTI)

A device for reclaiming heat from stove pipes and the like. A semi-circular shaped hollow enclosed housing with a highly thermal-conductive concave surface is mounted contactingly to surround approximately one-half of the circumference of the stove pipe. The concave surface is formed to contact the pipe at a maximum number of points along that surface. The hollow interior of the housing contains thin multi-surfaced projections which are integral with the concave surface and conductively transfer heat from the stove pipe and concave surface to heat the air in the housing. A fan blower is attached via an air conduit to an entrance opening in the housing. When turned on, the blower pushes the heated interior air out a plurality of air exit openings in the ends of the housing and brings in lower temperature outside air for heating.

Parham, F.

1985-04-09T23:59:59.000Z

316

Heat transfer. [heat transfer roller employing a heat pipe  

SciTech Connect

A heat transfer roller embodying a heat pipe is disclosed. The heat pipe is mounted on a shaft, and the shaft is adapted for rotation on its axis.

Sarcia, D.S.

1978-05-23T23:59:59.000Z

317

Experimental Research of Air Source Heat Pump Frosting and Defrosting in a Double Stage-Coupling Heat Pump  

E-Print Network (OSTI)

In a double stage-coupling heat pump, comprising an air source and water loop heat pump, the 13~20 ? low temperature water is supplied to the water loop heat pump unit. The water loop heat pump can extract heat from the water and heat the indoor air. The most common method of air source heat pump frost removal is reverse-cycle defrost. During the defrosting operation, the heat pump runs in the cooling mode. The defrost process is accomplished by reversing the normal heating mode. In this paper, the effect of the heat storage tank to the air source heat pump defrosting is test. Owing to the existence of the heat storage tank, thermal inertia of the loop is relatively high. The frosting and defrosting course of the air source heat pump have little effect on the room temperature.

Wang, Z.; Gu, J.; Lu, Z.

2006-01-01T23:59:59.000Z

318

Combined Cycle Cogeneration at NALCO Chemical  

E-Print Network (OSTI)

The Nalco Chemical Company, while expanding their corporate headquarters, elected to investigate the potential for cogeneration. The headquarters complex has a central physical plant for heating and chilling. The authors describe the analysis approach for determining the most economical system design. Generation capacity ranging from 2.7 MW up to 7.0 MW in both simple cycle cogeneration and combined cycle cogeneration was analyzed. Both single pressure and dual pressure waste heat boilers were included in the evaluation. In addition, absorption chilling and electrical centrifugal chilling capacity expansion were integrated into the model. The gas turbine selection procedure is outlined. Bid evaluation procedure involved a life cycle cost comparison wherein the bid specification responses for each model turbine were incorporated into the life cycle facility program. The recommendation for the facility is a 4.0MW combined cycle cogeneration system. This system is scheduled for startup in October of 1985. Most major equipment has been purchased and the building to house the system is nearing completion. A discussion of the purchase and scheduling integration will be included.

Thunem, C. B.; Jacobs, K. W.; Hanzel, W.

1985-05-01T23:59:59.000Z

319

Waste heat rejection from geothermal power stations  

DOE Green Energy (OSTI)

This study of waste heat rejection from geothermal power stations is concerned only with the heat rejected from the power cycle. The heat contained in reinjected or otherwise discharged geothermal fluids is not included with the waste heat considered here. The heat contained in the underflow from the flashtanks in such systems is not considered as part of the heat rejected from the power cycle. By following this definition of the waste heat to be rejected, various methods of waste heat dissipation are discussed without regard for the particular arrangement to obtain heat from the geothermal source. Recent conceptual design studies made for 50-MW(e) geothermal power stations at Heber and Niland, California, are of particular interst. The former uses a flashed-steam system and the latter a binary cycle that uses isopentane. In last-quarter 1976 dollars, the total estimated capital costs were about $750/kW and production costs about 50 mills/kWhr. If wet/dry towers were used to conserve 50% of the water evaporation at Heber, production costs would be about 65 mills/kWhr.

Robertson, R.C.

1978-12-01T23:59:59.000Z

320

VAPOR COMPRESSION HEAT PUMP SYSTEM FIELD TESTS AT THE TECH COMPLEX  

E-Print Network (OSTI)

, two conventional air- to-ir heat pumps, an air-to-air heat pump with desuperheater water heater for several novel and conventional heat pump systems for space conditioning and water heating. Systems tested include the Annual Cycle Energy System (ACES), solar assisted heat pumps (SAHP) both parallel and series

Oak Ridge National Laboratory

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Boiler Room Coal Drying Heat Exchanger Numerical Computational Simulation and Analysis  

Science Conference Proceedings (OSTI)

Northeast area city district heating boiler room of coal with high moisture content, have caused a large number of waste of coal resources. Boiler coal drying heat exchanger is a long design cycle, testing workload and investment is more equipment. In ... Keywords: District heating boiler room, Dry heat exchanger, Numerical simulation, Heat transfer calculation

Zhao Xuefeng, Xiong Wen-zhuo

2012-07-01T23:59:59.000Z

322

System Modeling of Gas Engine Driven Heat Pump  

SciTech Connect

To improve the system performance of the GHP, modeling and experimental study has been made by using desiccant system in cooling operation (particularly in high humidity operations) and suction line waste heat recovery to augment heating capacity and efficiency. The performance of overall GHP system has been simulated by using ORNL Modulating Heat Pump Design Software, which is used to predict steady-state heating and cooling performance of variable-speed vapor compression air-to-air heat pumps for a wide range of operational variables. The modeling includes: (1) GHP cycle without any performance improvements (suction liquid heat exchange and heat recovery) as a baseline (both in cooling and heating mode), (2) the GHP cycle in cooling mode with desiccant system regenerated by waste heat from engine incorporated, (3) GHP cycle in heating mode with heat recovery (recovered heat from engine). According to the system modeling results, by using desiccant system regenerated by waste heat from engine, the SHR can be lowered to 40%. The waste heat of the gas engine can boost the space heating efficiency by 25% in rated operating conditions.

Mahderekal, Isaac [Oak Ridge National Laboratory (ORNL); Shen, Bo [ORNL; Vineyard, Edward [Oak Ridge National Laboratory (ORNL)

2012-01-01T23:59:59.000Z

323

Heat Recovery Steam Generator (HRSG) Chemical Cleaning Guidelines Case Studies  

Science Conference Proceedings (OSTI)

A considerable number of combined cycle units with heat recovery steam generators (HRSGs) were installed over the past two decades worldwide, and the design complexity and operating pressures of these units increased significantly during this period. One of the goals of EPRI's Heat Recovery Steam Generator (HRSG) Dependability Program 88 is to minimize availability losses associated with HRSG tube failures. To support its members operating combined cycle units, EPRI published Heat Recovery Steam Generato...

2006-11-13T23:59:59.000Z

324

Technology Assessment Report: Duty Cycling Controllers Revisited  

SciTech Connect

This report covers an assessment of two brands of energy management controllers that are currently being offered that utilize the principle of duty cycling to purportedly save energy for unitary air conditioners and heat pumps, gas furnaces, and gas fired boilers. The results of an extensive review of past research on this subject as well as a review of vendor sponsored field testing of these controllers compares these newer controllers to those of the past. Included also is a discussion of how the duty cycling principle is prone to misinterpretation as to its potential to save energy.

Webster, Tom; Benenson, Peter

1998-05-01T23:59:59.000Z

325

Analysis of Energy, Environmental and Life Cycle Cost Reduction Potential  

Open Energy Info (EERE)

Environmental and Life Cycle Cost Reduction Potential Environmental and Life Cycle Cost Reduction Potential of Ground Source Heat Pump (GSHP) in Hot and Humid Climate Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Analysis of Energy, Environmental and Life Cycle Cost Reduction Potential of Ground Source Heat Pump (GSHP) in Hot and Humid Climate Project Type / Topic 1 Recovery Act - Geothermal Technologies Program: Ground Source Heat Pumps Project Type / Topic 2 Topic Area 2: Data Gathering and Analysis Project Description It has been widely recognized that the energy saving benefits of GSHP systems are best realized in the northern and central regions where heating needs are dominant or both heating and cooling loads are comparable. For hot and humid climate such as in the states of FL, LA, TX, southern AL, MS, GA, NC and SC, buildings have much larger cooling needs than heating needs. The Hybrid GSHP (HGSHP) systems therefore have been developed and installed in some locations of those states, which use additional heat sinks (such as cooling tower, domestic water heating systems) to reject excess heat. Despite the development of HGSHP the comprehensive analysis of their benefits and barriers for wide application has been limited and often yields non-conclusive results. In general, GSHP/HGSHP systems often have higher first costs than conventional systems making short-term economics unattractive. Addressing these technical and financial barriers call for additional evaluation of innovative utility programs, incentives and delivery approaches.

326

Heat collector  

DOE Patents (OSTI)

A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

Merrigan, Michael A. (Santa Cruz, NM)

1984-01-01T23:59:59.000Z

327

Heat collector  

DOE Patents (OSTI)

A heat collector and method suitable for efficiently and cheaply collecting solar and other thermal energy are provided. The collector employs a heat pipe in a gravity-assist mode and is not evacuated. The collector has many advantages, some of which include ease of assembly, reduced structural stresses on the heat pipe enclosure, and a low total materials cost requirement. Natural convective forces drive the collector, which after startup operates entirely passively due in part to differences in molecular weights of gaseous components within the collector.

Merrigan, M.A.

1981-06-29T23:59:59.000Z

328

Development of the household sample for furnace and boilerlife-cycle cost analysis  

Science Conference Proceedings (OSTI)

Residential household space heating energy use comprises close to half of all residential energy consumption. Currently, average space heating use by household is 43.9 Mbtu for a year. An average, however, does not reflect regional variation in heating practices, energy costs, or fuel type. Indeed, a national average does not capture regional or consumer group cost impacts from changing efficiency levels of heating equipment. The US Department of Energy sets energy standards for residential appliances in, what is called, a rulemaking process. The residential furnace and boiler efficiency rulemaking process investigates the costs and benefits of possible updates to the current minimum efficiency regulations. Lawrence Berkeley National Laboratory (LBNL) selected the sample used in the residential furnace and boiler efficiency rulemaking from publically available data representing United States residences. The sample represents 107 million households in the country. The data sample provides the household energy consumption and energy price inputs to the life-cycle cost analysis segment of the furnace and boiler rulemaking. This paper describes the choice of criteria to select the sample of houses used in the rulemaking process. The process of data extraction is detailed in the appendices and is easily duplicated. The life-cycle cost is calculated in two ways with a household marginal energy price and a national average energy price. The LCC results show that using an national average energy price produces higher LCC savings but does not reflect regional differences in energy price.

Whitehead, Camilla Dunham; Franco, Victor; Lekov, Alex; Lutz, Jim

2005-05-31T23:59:59.000Z

329

MHK Technologies/Open Cycle OTEC | Open Energy Information  

Open Energy Info (EERE)

OTEC OTEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Open Cycle OTEC.jpg Technology Profile Primary Organization Ocean Engineering and Energy Systems Technology Resource Click here OTEC Technology Type Click here OTEC - Open Cycle Technology Readiness Level Click here TRL 1 3 Discovery Concept Def Early Stage Dev Design Engineering Technology Description Closed Cycle OTEC In the closed cycle OTEC system warm seawater vaporizes a working fluid such as ammonia flowing through a heat exchanger evaporator The vapor expands at moderate pressures and turns a turbine coupled to a generator that produces electricity The vapor is then condensed in another heat exchanger condenser using cold seawater pumped from the ocean s depths through a cold water pipe The condensed working fluid is pumped back to the evaporator to repeat the cycle The working fluid remains in a

330

High temperature heat pipes for waste heat recovery  

SciTech Connect

Operation of heat pipes in air at temperatures above 1200/sup 0/K has been accomplished using SiC as a shell material and a chemical vapor deposit (CVD) tungsten inner liner for protection of the ceramic from the sodium working fluid. The CVD tungsten has been used as a distribution wick for the gravity assisted heat pipe through the development of a columnar tungsten surface structure, achieved by control of the metal vapor deposition rate. Wick performance has been demonstrated in tests at approximately 2 kW throughput with a 19-mm-i.d. SiC heat pipe. Operation of ceramic heat pipes in repeated start cycle tests has demonstrated their ability to withstand temperature rise rates of greater than 1.2 K/s.

Merrigan, M.A.; Keddy, E.S.

1980-01-01T23:59:59.000Z

331

High efficiency carbonate fuel cell/turbine hybrid power cycle  

Science Conference Proceedings (OSTI)

The hybrid power cycle studies were conducted to identify a high efficiency, economically competitive system. A hybrid power cycle which generates power at an LHV efficiency > 70% was identified that includes an atmospheric pressure direct carbonate fuel cell, a gas turbine, and a steam cycle. In this cycle, natural gas fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming fuel. The mixed gas then flows to a direct carbonate fuel cell which generates about 70% of the power. The portion of the anode exhaust which is not recycled is burned and heat transferred through a heat exchanger (HX) to the compressed air from a gas turbine. The heated compressed air is then heated further in the gas turbine burner and expands through the turbine generating 15% of the power. Half the exhaust from the turbine provides air for the anode exhaust burner. All of the turbine exhaust eventually flows through the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Exhaust from the cathodes flows to a steam system (heat recovery steam generator, staged steam turbine generating 15% of the cycle power). Simulation of a 200 MW plant with a hybrid power cycle had an LHV efficiency of 72.6%. Power output and efficiency are insensitive to ambient temperature, compared to a gas turbine combined cycle; NOx emissions are 75% lower. Estimated cost of electricity for 200 MW is 46 mills/kWh, which is competitive with combined cycle where fuel cost is > $5.8/MMBTU. Key requirement is HX; in the 200 MW plant studies, a HX operating at 1094 C using high temperature HX technology currently under development by METC for coal gassifiers was assumed. A study of a near term (20 MW) high efficiency direct carbonate fuel cell/turbine hybrid power cycle has also been completed.

Steinfeld, G.; Maru, H.C. [Energy Research Corp., Danbury, CT (United States); Sanderson, R.A. [Sanderson (Robert) and Associates, Wethersfield, CT (United States)

1996-07-01T23:59:59.000Z

332

Energy Basics: Heat Pump Systems  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating Heat...

333

Compare All CBECS Activities: District Heat Use  

U.S. Energy Information Administration (EIA) Indexed Site

District Heat Use District Heat Use Compare Activities by ... District Heat Use Total District Heat Consumption by Building Type Commercial buildings in the U.S. used a total of approximately 433 trillion Btu of district heat (district steam or district hot water) in 1999. There were only five building types with statistically significant district heat consumption; education buildings used the most total district heat. Figure showing total district heat consumption by building type. If you need assistance viewing this page, please call 202-586-8800. District Heat Consumption per Building by Building Type Health care buildings used the most district heat per building. Figure showing district heat consumption per building by building type. If you need assistance viewing this page, please call 202-586-8800.

334

MHK Technologies/Kalina Cycle OTEC | Open Energy Information  

Open Energy Info (EERE)

Kalina Cycle OTEC Kalina Cycle OTEC < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Kalina Cycle OTEC.jpg Technology Profile Primary Organization Ocean Engineering and Energy Systems Technology Resource Click here OTEC Technology Type Click here OTEC - Closed Cycle Technology Description Kalina Cycle The Kalina Cycle is a variation of the more conventional closed cycle OTEC system incorporating aqueous ammonia ammonia water mixture as the working fluid instead of the conventional ammonia or propylene working fluid employed in earlier designs of closed cycle OTEC power systems The Kalina Cycle is a break through technology for OTEC power systems providing a nearly 80 increase in efficiency over previous closed cycle designs Because the ammonia water concentrations can be varied throughout the system to optimize according to system temperatures sort of a designer working fluid and by adding an extra component the recuperator heat losses generally experienced in other closed cycle designs can be minimized and recovered thereby improving the overall efficiency of the power cycle

335

Duty Cycle Software  

Duty cycles capture the influence of one variable in relations to the whole system. This allows for analysis in determining the impact of new ...

336

Cycles in fossil diversity  

E-Print Network (OSTI)

Transitions in Global Marine Diversity, Science 281, 1157-know if this cycle is a variation in true diversity or onlyin observed diversity, but either case requires explanation

Rohde, Robert A.; Muller, Richard A.

2004-01-01T23:59:59.000Z

337

Heat reclaimer  

SciTech Connect

An apparatus for reclaiming heat from the discharge gas from a combustion fuel heating unit, which has: inlet and outlet sections; an expansion section whose circumference gradually increases in the direction of flow, thereby providing an increased area for heat transfer; flow splitter plates which lie within and act in conjunction with the expansion section wall to form flow compartments, which flow splitter plates and expansion section wall have a slope, with respect to the centroidal axis of the flow compartment not exceeding 0.1228, which geometry prevents a separation of the flow from the enclosing walls, thereby increasing heat transfer and maintaining the drafting function; and a reduction section which converges the flow to the outlet section.

Horkey, E.J.

1982-06-29T23:59:59.000Z

338

HEAT EXCHANGER  

DOE Patents (OSTI)

A heat exchanger is designed for use in the transfer of heat between a radioactive fiuid and a non-radioactive fiuid. The exchanger employs a removable section containing the non-hazardous fluid extending into the section designed to contain the radioactive fluid. The removable section is provided with a construction to cancel out thermal stresses. The stationary section is pressurized to prevent leakage of the radioactive fiuid and to maintain a safe, desirable level for this fiuid. (AEC)

Fox, T.H. III; Richey, T. Jr.; Winders, G.R.

1962-10-23T23:59:59.000Z

339

Corrosive resistant heat exchanger  

DOE Patents (OSTI)

A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

Richlen, Scott L. (Annandale, VA)

1989-01-01T23:59:59.000Z

340

Power systems utilizing the heat of produced formation fluid  

DOE Patents (OSTI)

Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method includes treating a hydrocarbon containing formation. The method may include providing heat to the formation; producing heated fluid from the formation; and generating electricity from at least a portion of the heated fluid using a Kalina cycle.

Lambirth, Gene Richard (Houston, TX)

2011-01-11T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Water Vapor and Mechanical Work: A Comparison of Carnot and Steam Cycles  

Science Conference Proceedings (OSTI)

The impact of water vapor on the production of kinetic energy in the atmosphere is discussed here by comparing two idealized heat engines: the Carnot cycle and the steam cycle. A steam cycle transports water from a warm moist source to a colder ...

Olivier Pauluis

2011-01-01T23:59:59.000Z

342

Technology assessments of advanced power generation systems 2: Kalina bottoming cycle: Final report  

SciTech Connect

A preliminary assessment of the Kalina cycle as the bottoming system of a small, combined-cycle power plant found that the cost of electricity for this plant was calculated to be somewhat less than that of competing steam-bottoming systems. This new system requires further analysis, however, particularly of the trade-off between heat exchanger cost and cycle performance.

1986-11-01T23:59:59.000Z

343

Technology Assessments of Advanced Power Generation Systems II--Kalina Bottoming Cycle  

Science Conference Proceedings (OSTI)

A preliminary assessment of the Kalina cycle as the bottoming system of a small, combined-cycle power plant found that the cost of electricity for this plant was calculated to be somewhat less than that of competing steam-bottoming systems. This new system requires further analysis, however, particularly of the trade-off between heat exchanger cost and cycle performance.

1986-11-14T23:59:59.000Z

344

Transportation implications of a closed fuel cycle.  

Science Conference Proceedings (OSTI)

Transportation for each step of a closed fuel cycle is analyzed in consideration of the availability of appropriate transportation infrastructure. The United States has both experience and certified casks for transportation that may be required by this cycle, except for the transport of fresh and used MOX fuel and fresh and used Advanced Burner Reactor (ABR) fuel. Packaging that had been used for other fuel with somewhat similar characteristics may be appropriate for these fuels, but would be inefficient. Therefore, the required neutron and gamma shielding, heat dissipation, and criticality were calculated for MOX and ABR fresh and spent fuel. Criticality would not be an issue, but the packaging design would need to balance neutron shielding and regulatory heat dissipation requirements.

Bullard, Tim (University of Nevada - Reno); Bays, Samuel (Idaho National Laboratory); Dennis, Matthew L.; Weiner, Ruth F.; Sorenson, Ken Bryce; Dixon, Brent (Idaho National Laboratory); Greiner, Miles (University of Nevada - Reno)

2010-10-01T23:59:59.000Z

345

Split stream boilers for high-temperature/high-pressure topping steam turbine combined cycles  

SciTech Connect

Research and development work on high-temperature and high-pressure (up to 1,500 F TIT and 4,500 psia) topping steam turbines and associated steam generators for steam power plants as well as combined cycle plants is being carried forward by DOE, EPRI, and independent companies. Aeroderivative gas turbines and heavy-duty gas turbines both will require exhaust gas supplementary firing to achieve high throttle temperatures. This paper presents an analysis and examples of a split stream boiler arrangement for high-temperature and high-pressure topping steam turbine combined cycles. A portion of the gas turbine exhaust flow is run in parallel with a conventional heat recovery steam generator (HRSG). This side stream is supplementary fired opposed to the current practice of full exhaust flow firing. Chemical fuel gas recuperation can be incorporated in the side stream as an option. A significant combined cycle efficiency gain of 2 to 4 percentage points can be realized using this split stream approach. Calculations and graphs show how the DOE goal of 60 percent combined cycle efficiency burning natural gas fuel can be exceeded. The boiler concept is equally applicable to the integrated coal gas fuel combined cycle (IGCC).

Rice, I.G. [Rice (I.G.), Spring, TX (United States)

1997-04-01T23:59:59.000Z

346

COMPARATIVE STUDY AMONG HYBRID GROUND SOURCE HEAT PUMP SYSTEM, COMPLETE GROUND SOURCE HEAT PUMP AND CONVENTIONAL HVAC SYSTEM  

DOE Green Energy (OSTI)

In this paper, a hotel with hybrid geothermal heat pump system (HyGSHP) in the Pensacola is selected and simulated by the transient simulation software package TRNSYS [1]. To verify the simulation results, the validations are conducted by using the monthly average entering water temperature, monthly facility consumption data, and etc. And three types of HVAC systems are compared based on the same building model and HVAC system capacity. The results are presented to show the advantages and disadvantages of HyGSHP compared with the other two systems in terms of energy consumptions, life cycle cost analysis.

Jiang Zhu; Yong X. Tao

2011-11-01T23:59:59.000Z

347

Power Plant Cycling Costs  

Science Conference Proceedings (OSTI)

This report provides a detailed review of the most up to date data available on power plant cycling costs. The primary objective of this report is to increase awareness of power plant cycling cost, the use of these costs in renewable integration studies and to stimulate debate between policymakers, system dispatchers, plant personnel and power utilities.

Kumar, N.; Besuner, P.; Lefton, S.; Agan, D.; Hilleman, D.

2012-07-01T23:59:59.000Z

348

Homes show greatest seasonal variation in electricity use ...  

U.S. Energy Information Administration (EIA)

Energy Information Administration ... solar, wind, geothermal, ... as changes in temperature and humidity affect the demand for space heating and cooling.

349

Federal Energy Management Trade Show | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Topic TOPICS Tax Credits, Rebates, Savings Energy Efficiency -Homes --Heating & Cooling --Home Weatherization ---Home Energy Audits ---Lighting ---Appliances & Electronics --Design...

350

The promise of the Kalina cycle  

SciTech Connect

New technologies come and go, but the Rankine steam cycle goes on forever - or so it seemed until Alexander I. Kalina found a better way. Power engineers have known for years that heat can be generated more efficiently in a boiler if a mixture like ammonia and water is used as the working fluid, but no one had figured out how to condense the working fluid mixture at normal heat rejection temperatures. Kalina solved the problem, at least in theory. Now it must be determined whether his theory holds up in practice. In the Rankine steam cycle, water is used in a boiler to produce high-pressure vapor, which is expanded through a turbine to produce power. The expanded vapor is subsequently condensed and is pumped back to the boiler in liquid form to repeat the cycle. In the Kalina cycle, a mixture of approximately 70 percent ammonia and 30 percent water is used in a boiler to produce superheated vapor. The ammonia begins to boil first, having the lower boiling point. As the ammonia boils off, the concentration of ammonia in the remaining mixture decreases, and the mixture's boiling point increases. The boiling point keeps changing as the ammonia-water ratio changes, and the fluid mixture is gradually depleted. This leads to a better match in temperature profiles and permits more energy to be transferred to the working fluid. Overall, more of the available heat is utilized in vapor production than in the steam cycle, and more vapor means more power output from the turbine-generator.

Jurgen, R.K.

1986-04-01T23:59:59.000Z

351

System dynamics based models for selecting HVAC systems for office buildings: a life cycle assessment from carbon emissions perspective.  

E-Print Network (OSTI)

??This study aims to explore the life cycle environmental impacts of typical heating ventilation and air condition (HVAC) systems including variable air volume (VAV) system,… (more)

Chen, S

2011-01-01T23:59:59.000Z

352

Low emission advanced power cycle. Final CRADA report.  

SciTech Connect

Today's gas turbines are based on the Brayton Cycle in which heat is added to the working fluid at constant pressure. An alternate approach, the Humphrey cycle, provides a higher theoretical thermal efficiency by adding heat at constant, or near constant volume. A few practical examples of such engines appeared in the mid 1900's, but they were largely superseded by the Brayton engine. Although the conventional gas turbine has been developed to a high level of efficiency and reliability, significant improvements in performance are becoming increasingly costly to obtain. Efficiencies of compressors, turbines and combustors are approaching theoretical limits. Cooling and materials technologies continue to improve but higher cycle temperatures may be limited by NOx emissions. While heat exchangers, intercoolers and other features improve cycle efficiency they add significantly to the cost, weight and volume of the basic engine and for flight applications may always be impractical. For these reasons there has been renewed interest in recent years in the constant volume Humphrey cycle focusing mainly on pulsing systems in which heat is added by a rapid series of detonations. Variations on this basic scheme are being evaluated for aircraft propulsions systems. General Electric has established a joint program with several Russian organizations to explore devices based on pressure rise combustion cycle and to make fundamental measurements of detonation properties of mixtures of hydrocarbon fuels and air.

Tentner, A.; Nuclear Engineering Division

2010-07-13T23:59:59.000Z

353

Studies on the LASL cadmium-cadmium carbonate cycle  

DOE Green Energy (OSTI)

The following results were obtained from studies on the cadmium-cadmium carbonate cycle. A new lower limit for the heat of formation of CdO(g) has been estimated ..delta..H/sup 0//sub f,298/ > 113.8 kJ/mol. Hydrogen production is subject to catalysis. While Pd is an effective catalyst, NH/sub 4/Cl shows greater catalytic activity. Seventy-two percent of the total available H/sub 2/ is formed in one-half hour at 523/sup 0/K using NH/sub 4/Cl as a catalyst. Four to five moles of water must be removed from CdCO/sub 3/ prior to its thermal decomposition.

Mason, C.F.V.; Bowman, M.G.; Behrens, R.G.

1980-01-01T23:59:59.000Z

354

Heating Rate Profiles in Galaxy Clusters  

E-Print Network (OSTI)

In recent years evidence has accumulated suggesting that the gas in galaxy clusters is heated by non-gravitational processes. Here we calculate the heating rates required to maintain a physically motived mass flow rate, in a sample of seven galaxy clusters. We employ the spectroscopic mass deposition rates as an observational input along with temperature and density data for each cluster. On energetic grounds we find that thermal conduction could provide the necessary heating for A2199, Perseus, A1795 and A478. However, the suppression factor, of the clasical Spitzer value, is a different function of radius for each cluster. Based on the observations of plasma bubbles we also calculate the duty cycles for each AGN, in the absence of thermal conduction, which can provide the required energy input. With the exception of Hydra-A it appears that each of the other AGNs in our sample require duty cycles of roughly $10^{6}-10^{7}$ yrs to provide their steady-state heating requirements. If these duty cycles are unrealistic, this may imply that many galaxy clusters must be heated by very powerful Hydra-A type events interspersed between more frequent smaller-scale outbursts. The suppression factors for the thermal conductivity required for combined heating by AGN and thermal conduction are generally acceptable. However, these suppression factors still require `fine-tuning` of the thermal conductivity as a function of radius. As a consequence of this work we present the AGN duty cycle as a cooling flow diagnostic.

Edward C. D. Pope; Georgi Pavlovski; Christian R. Kaiser; Hans Fangohr

2006-01-05T23:59:59.000Z

355

Biomass Gasification Combined Cycle  

DOE Green Energy (OSTI)

Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

Judith A. Kieffer

2000-07-01T23:59:59.000Z

356

EVALUATION OF A SULFUR OXIDE CHEMICAL HEAT STORAGE PROCESS FOR A STEAM SOLAR ELECTRIC PLANT  

E-Print Network (OSTI)

Flows and stream conditions in steam power cycle. Table 4.1in the low-temperature reactor system. Steam power cycle 8.1Heat Storage System for a Solar Steam Power Plant." 12th

Dayan, J.

2011-01-01T23:59:59.000Z

357

Method and apparatus for fuel gas moisturization and heating  

SciTech Connect

Fuel gas is saturated with water heated with a heat recovery steam generator heat source. The heat source is preferably a water heating section downstream of the lower pressure evaporator to provide better temperature matching between the hot and cold heat exchange streams in that portion of the heat recovery steam generator. The increased gas mass flow due to the addition of moisture results in increased power output from the gas and steam turbines. Fuel gas saturation is followed by superheating the fuel, preferably with bottom cycle heat sources, resulting in a larger thermal efficiency gain compared to current fuel heating methods. There is a gain in power output compared to no fuel heating, even when heating the fuel to above the LP steam temperature.

Ranasinghe, Jatila (Niskayuna, NY); Smith, Raub Warfield (Ballston Lake, NY)

2002-01-01T23:59:59.000Z

358

Recovering heat when generating power  

Science Conference Proceedings (OSTI)

Intelligent use of heat-recovery stream generators (HRSGs) is vital for the efficient operation of cogeneration plants, which furnish both thermal energy (usually in the form of steam) and electric energy. HRSGs are similarly important in combined-cycle power plants, in which the thermal energy rejected from the primary electric-power-generation step is harnessed (as discussed below) to produce additional electrical energy. In these facilities, the HRSG is typically heated by gas-turbine exhaust. Natural gas is the fuel most widely used for gas turbines in the U.S., whereas fuel oil is the main fuel in other countries. Depending on the amount of steam to be produced, HRSGs for gas-turbine-exhaust applications may be unfired, supplementary-fired or furnace fired. The paper describes these three options; the pressure drop encountered in all three systems; the Cheng cycle; catalytic reduction of nitrogen oxides and CO; and performance testing.

Ganapathy, V.

1993-02-01T23:59:59.000Z

359

Avestar® - Syngas-Fired Combined Cycle Dynamic Simulator  

NLE Websites -- All DOE Office Websites (Extended Search)

Syngas-Fired Combined Cycle Dynamic Simulator Syngas-Fired Combined Cycle Dynamic Simulator The AVESTAR® center offers courses using the Combined Cycle Simulator, focusing on the power generation process after gasification. This simulator is well-suited for concentrated training on operation and control of the gas and steam turbines; condensate, feed water, and circulating water systems; heat recovery steam generator; and selective catalytic reduction (SCR) unit. Combined cycle simulator startup operations include bringing up the gas turbine to rated speed on natural gas and then switching over to the firing of synthesis gas. Key capabilities of the Combined Cycle Simulator include: Combined Cycle Simulator Operator training station HMI display for overview of Gas Turbine - Train A Normal base load operation

360

HEAT GENERATION  

DOE Patents (OSTI)

Heat is generated by the utilization of high energy neutrons produced as by nuclear reactions between hydrogen isotopes in a blanket zone containing lithium, a neutron moderator, and uranium and/or thorium effective to achieve multtplicatton of the high energy neutron. The rnultiplied and moderated neutrons produced react further with lithium-6 to produce tritium in the blanket. Thermal neutron fissionable materials are also produced and consumed in situ in the blanket zone. The heat produced by the aggregate of the various nuclear reactions is then withdrawn from the blanket zone to be used or otherwise disposed externally. (AEC)

Imhoff, D.H.; Harker, W.H.

1963-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

PIA - Northeast Home Heating Oil Reserve System (Heating Oil...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating Oil)...

362

PIA - Northeast Home Heating Oil Reserve System (Heating Oil...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

PIA - Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating Oil) PIA - Northeast Home Heating Oil Reserve System (Heating...

363

Thermal Design of an Ultrahigh Temperature Vapor Core Reactor Combined Cycle Nuclear Power Plant  

SciTech Connect

Current work modeling high temperature compact heat exchangers may demonstrate the design feasibility of a Vapor Core Reactor (VCR) driven combined cycle power plant. For solid nuclear fuel designs, the cycle efficiency is typically limited by a metallurgical temperature limit which is dictated by fuel and structural melting points. In a vapor core, the gas/vapor phase nuclear fuel is uniformly mixed with the topping cycle working fluid. Heat is generated homogeneously throughout the working fluid thus extending the metallurgical temperature limit. Because of the high temperature, magnetohydrodynamic (MHD) generation is employed for topping cycle power extraction. MHD rejected heat is transported via compact heat exchanger to a conventional Brayton gas turbine bottoming cycle. High bottoming cycle mass flow rates are required to remove the waste heat because of low heat capacities for the bottoming cycle gas. High mass flow is also necessary to balance the high Uranium Tetrafluoride (UF{sub 4}) mass flow rate in the topping cycle. Heat exchanger design is critical due to the high temperatures and corrosive influence of fluoride compounds and fission products existing in VCR/MHD exhaust. Working fluid compositions for the topping cycle include variations of Uranium Tetrafluoride, Helium and various electrical conductivity seeds for the MHD. Bottoming cycle working fluid compositions include variations of Helium and Xenon. Some thought has been given to include liquid metal vapor in the bottoming cycle for a Cheng or evaporative cooled design enhancement. The NASA Glenn Lewis Research Center code Chemical Equilibrium with Applications (CEA) is utilized for evaluating chemical species existing in the gas stream. Work being conducted demonstrates the compact heat exchanger design, utilization of the CEA code, and assessment of different topping and bottoming working fluid compositions. (authors)

Bays, Samuel E.; Anghaie, Samim; Smith, Blair; Knight, Travis [Innovative Space Power and Propulsion Institute, University of Florida, 202 Nuclear Science Building, Gainesville, FL 32611 (United States)

2004-07-01T23:59:59.000Z

364

A nano heat engine beyond the Carnot limit  

E-Print Network (OSTI)

Heat engines extract work by running cyclically between two heat reservoirs. When the two reservoirs are thermal and at different temperatures, the maximum efficiency of the engine is given by the Carnot limit. Here we consider a quantum Otto cycle for a time-dependent harmonic oscillator coupled to an engineered squeezed thermal reservoir. We show that the efficiency at maximum power increases with the degree of squeezing, exponentially approaching unity for large squeezing parameters $r$. Furthermore, we propose an experimental scheme to implement such a system by using a single trapped ion in a linear Paul trap with special geometry and coupled to engineered reservoirs. Our analytical investigations are supported with Monte Carlo simulations that demonstrate the feasibility of our proposal. For realistic trap parameters, an increase of up to a factor of four is reached, largely exceeding the classical limit.

Johannes Roßnagel; Obinna Abah; Ferdinand Schmidt-Kaler; Kilian Singer; Eric Lutz

2013-08-27T23:59:59.000Z

365

Finding good candidate cycles for efficient p-cycle network design  

E-Print Network (OSTI)

Abstract- An important problem in p-cycle network design is to find a set of p-cycles to protect a given working capacity distribution so that the total spare capacity used by the p-cycles is minimized. Existing approaches for solving the problem include ILP and heuristic algorithm. Both require a set of candidate p-cycles to be precomputed. In this paper, we propose an algorithm to compute a small set of candidate p-cycles that can lead to good performance when used by ILP or the heuristic algorithm. The key idea of the algorithm is to generate a combination of high efficiency cycles and short cycles so that both densely distributed and sparsely distributed working capacities can he efficiently protected by the candidate cycles. The algorithm is also flexible in that the number of cycles generated is controlled by an input parameter. Simulation study showed that the cycles generated by our algorithm can lead to near optimal solutions when used by

Chang Liu; Lu Rum

2004-01-01T23:59:59.000Z

366

Heat reclaimer  

Science Conference Proceedings (OSTI)

A heat reclaimer for the exhaust flue of a heating unit comprises a housing having an air input space, an air output space, and an exhaust space, with a plurality of tubes connected between and communicating the air input space with the air output space and extending through the exhaust space. The exhaust flue of the heating unit is connected into the exhaust space of the housing and an exhaust output is connected to the housing extending from the exhaust space for venting exhaust coming from the heater into the exhaust space to a chimney, for example. A float or level switch is connected to the housing near the bottom of the exhaust space for switching, for example, an alarm if water accumulates in the exhaust space from condensed water vapor in the exhaust. At least one hole is also provided in the housing above the level of the float switch to permit condensed water to leave the exhaust space. The hole is provided in case the float switch clogs with soot. A wiping device may also be provided in the exhaust space for wiping the exterior surfaces of the tubes and removing films of water and soot which might accumulate thereon and reduce their heat transfer capacity.

Bellaff, L.

1981-10-20T23:59:59.000Z

367

Heat exchanger  

DOE Patents (OSTI)

A heat exchanger of the straight tube type in which different rates of thermal expansion between the straight tubes and the supply pipes furnishing fluid to those tubes do not result in tube failures. The supply pipes each contain a section which is of helical configuration.

Wolowodiuk, Walter (New Providence, NJ)

1976-01-06T23:59:59.000Z

368

A Better Steam Engine: Designing a Distributed Concentrating Solar Combined Heat and Power System  

E-Print Network (OSTI)

Vacuum tube liquid-vapor (heat-pipe) collectors. Proceedingsheat rejection in a condenser across a temperature gradient. This cycle ignores pressure losses in the pipes,

Norwood, Zachary Mills

2011-01-01T23:59:59.000Z

369

Waste heat driven absorption refrigeration process and system  

DOE Patents (OSTI)

Absorption cycle refrigeration processes and systems are provided which are driven by the sensible waste heat available from industrial processes and other sources. Systems are disclosed which provide a chilled water output which can be used for comfort conditioning or the like which utilize heat from sensible waste heat sources at temperatures of less than 170.degree. F. Countercurrent flow equipment is also provided to increase the efficiency of the systems and increase the utilization of available heat.

Wilkinson, William H. (Columbus, OH)

1982-01-01T23:59:59.000Z

370

Energy Basics: Absorption Heat Pumps  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating...

371

Energy Basics: Geothermal Heat Pumps  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Systems Air-Source Heat Pumps Ductless Mini-Split Heat Pumps Absorption Heat Pumps Geothermal Heat Pumps Supporting Equipment for Heating & Cooling Systems Water Heating...

372

The Carbon Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

The Carbon Cycle The Carbon Cycle The global carbon cycle involves the carbon in and exchanging between the earth's atmosphere, fossil fuels, the oceans, and the vegetation and soils of the earth's terrestrial ecosystems. image Each year, the world's terrestrial ecosystems withdraw carbon from the atmosphere through photosynthesis and add it again through respiration and decay. A more detailed look at the global carbon cycle for the 1990s is shown below. The main annual fluxes in GtC yr-1 are: pre-industrial "natural" fluxes in black and "anthropogenic" fluxes in red (modified from Sarmiento and Gruber, 2006, with changes in pool sizes from Sabine et al., 2004a). The net terrestrial loss of -39 GtC is inferred from cumulative fossil fuel emissions minus atmospheric increase minus ocean storage. The loss of

373

Cycle Chemistry Improvement Program  

Science Conference Proceedings (OSTI)

The purity of water and steam is central to ensuring fossil plant component availability and reliability. This report, which describes formal cycle chemistry improvement programs at nine utilities, will assist utilities in achieving significant operation and maintenance cost reductions.

1997-04-21T23:59:59.000Z

374

The Annual Agricultural Cycle  

E-Print Network (OSTI)

. Sman shad agriculture 1.WAV Length of track 00:44:03 Related tracks (include description/relationship if appropriate) Title of track The Annual Agricultural Cycle Translation of title Description (to be used in archive entry...

Zla ba sgrol ma

2009-11-16T23:59:59.000Z

375

Combined-cycle plants can challenge feedwater control  

Science Conference Proceedings (OSTI)

Stable feedwater control is critical to the reliable operation of any power plant steam generator system. This is particularly true for combustion turbine/heat recovery steam generator/steam turbine combined-cycle power plants where steam production may have to be sustained under varying modes of operation. Feedwater control system implementation in this type of installation often requires specialized designs to accommodate equipment limitations and the system's process dynamics. In particular, combined-cycle power plants that include integral deaerator and multiple pressure heat recovery steam generators may pose special control challenges in several areas. These include integral deaerator pressure, boiler feed pump recirculation control, boiler feed pump protective interlocks, and drum level control. This article describes a number of basic feedwater control logic features, derived from conventional fired boiler designs adapted for specific cycle configuration, applied in recent medium and large combustion turbine-heat recovery steam generator projects.

Bossio, R.A.

1994-03-01T23:59:59.000Z

376

NREL: Energy Analysis - Hydropower Results - Life Cycle Assessment...  

NLE Websites -- All DOE Office Websites (Extended Search)

Special Report on Renewable Energy Sources and Climate Change Mitigation: Hydropower OpenEI: Data, Visualization, and Bibliographies Chart that shows life cycle greenhouse gas...

377

Conceptual design and techno-economic assessment of integrated solar combined cycle system with DSG technology  

SciTech Connect

Direct steam generation (DSG) in parabolic trough collectors causes an increase to competitiveness of solar thermal power plants (STPP) by substitution of oil with direct steam generation that results in lower investment and operating costs. In this study the integrated solar combined cycle system with DSG technology is introduced and techno-economic assessment of this plant is reported compared with two conventional cases. Three considered cases are: an integrated solar combined cycle system with DSG technology (ISCCS-DSG), a solar electric generating system (SEGS), and an integrated solar combined cycle system with HTF (heat transfer fluid) technology (ISCCS-HTF). This study shows that levelized energy cost (LEC) for the ISCCS-DSG is lower than the two other cases due to reducing O and M costs and also due to increasing the heat to electricity net efficiency of the power plant. Among the three STPPs, SEGS has the lowest CO{sub 2} emissions, but it will operate during daytime only. (author)

Nezammahalleh, H.; Farhadi, F.; Tanhaemami, M. [Chemical and Petroleum Engineering Department, Sharif University of Technology, No 593 Azadi Ave., Tehran (Iran)

2010-09-15T23:59:59.000Z

378

Fast power cycle for fusion reactors  

SciTech Connect

The unique, deep penetration capability of 14 MeV neutrons produced in DT fusion reactions allows the generation of very high temperature working fluid temperatures in a thermal power cycle. In the FAST (Fusion Augmented Steam Turbine) power cycle steam is directly superheated by the high temperature ceramic refractory interior of the blanket, after being generated by heat extracted from the relatively cool blanket structure. The steam is then passed to a high temperature gas turbine for power generation. Cycle studies have been carried out for a range of turbine inlet temperatures (1600/sup 0/F to 3000/sup 0/F (870 to 1650/sup 0/C)), number of reheats, turbine mechanical efficiency, recuperator effectiveness, and system pressure losses. Gross cycle efficiency is projected to be in the range of 55 to 60%, (fusion energy to electric power), depending on parameters selected. Turbine inlet temperatures above 2000/sup 0/F, while they do increase efficiency somewhat, are not necessarily for high cycle efficiency.

Powell, J.; Fillo, J.; Makowitz, H.

1978-01-01T23:59:59.000Z

379

Life Cycle Analysis and Energy Conservation Standards for State Buildings |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Life Cycle Analysis and Energy Conservation Standards for State Life Cycle Analysis and Energy Conservation Standards for State Buildings Life Cycle Analysis and Energy Conservation Standards for State Buildings < Back Eligibility Institutional Schools State Government Savings Category Heating & Cooling Home Weatherization Construction Commercial Weatherization Commercial Heating & Cooling Design & Remodeling Manufacturing Buying & Making Electricity Program Info State Ohio Program Type Energy Standards for Public Buildings Provider Ohio State Architect's Office In 1995 Ohio passed legislation requiring that all state agencies perform life-cycle cost analyses prior to the construction of new buildings, and energy consumption analyses prior to new leases. Both analyses are to be primary considerations in either building design or leasing decisions. The

380

Implications of high efficiency power cycles for fusion reactor design  

SciTech Connect

The implications of the High Efficiency Power Cycle for fusion reactors are examined. The proposed cycle converts most all of the high grade CTR heat input to electricity. A low grade thermal input (T approximately 100$sup 0$C) is also required, and this can be supplied at low cost geothermal energy at many locations in the U. S. Approximately 3 KW of low grade heat is required per KW of electrical output. The thermodynamics and process features of the proposed cycle are discussed. Its advantages for CTR's are that low Q machines (e.g. driven Tokamaks, mirrors) can operate with a high (approximately 80 percent) conversion of CTR fusion energy to electricity, where with conventional power cycles no plant output could be achieved with such low Q operation. (auth)

Powell, J.R.; Usher, J.; Salzano, F.J.

1975-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Operation and analysis of a supercritical CO2 Brayton cycle.  

Science Conference Proceedings (OSTI)

Sandia National Laboratories is investigating advanced Brayton cycles using supercritical working fluids for use with solar, nuclear or fossil heat sources. The focus of this work has been on the supercritical CO{sub 2} cycle (S-CO2) which has the potential for high efficiency in the temperature range of interest for these heat sources, and is also very compact, with the potential for lower capital costs. The first step in the development of these advanced cycles was the construction of a small scale Brayton cycle loop, funded by the Laboratory Directed Research & Development program, to study the key issue of compression near the critical point of CO{sub 2}. This document outlines the design of the small scale loop, describes the major components, presents models of system performance, including losses, leakage, windage, compressor performance, and flow map predictions, and finally describes the experimental results that have been generated.

Wright, Steven Alan; Radel, Ross F.; Vernon, Milton E.; Pickard, Paul S.; Rochau, Gary Eugene

2010-09-01T23:59:59.000Z

382

Secular Cycles and Millennial Trends  

E-Print Network (OSTI)

both secular cycles and millennial up- ward trend dynamics.Cycles and Millennial Trends by Andrey Korotayev, ArtemySecular Cycles and Millennial Trends 1 Initially, we want to

Korotayev, Andrey V; Malkov, Artemy S; Khaltourina, Daria A

2006-01-01T23:59:59.000Z

383

IDENTIFICATION AND EXPERIMENTAL DATABASE FOR BINARY AND MULTICOMPONENT MIXTURES WITH POTENTIAL FOR INCREASING OVERALL CYCLE EFFICIENCY  

SciTech Connect

This report describes an experimental investigation designed to identify binary and multicomponent mixture systems that may be for increasing the overall efficiency of a coal fired unit by extracting heat from flue gases. While ammonia-water mixtures have shown promise for increasing cycle efficiencies in a Kalina cycle, the costs and associated range of thermal conditions involved in a heat recovery system may prohibit its use in a relatively low temperature heat recovery system. This investigation considered commercially available non-azeotropic binary mixtures with a boiling range applicable to a flue gas initially at 477.6 K (400 F) and developed an experimental database of boiling heat transfer coefficients for those mixtures. In addition to their potential as working fluids for increasing cycle efficiency, cost, ease of handling, toxicity, and environmental concerns were considered in selection of the mixture systems to be examined experimentally. Based on this review, water-glycol systems were identified as good candidates. However, previous investigations of mixture boiling have focused on aqueous hydrocarbon mixtures, where water is the heaviest component. There have been few studies of water-glycol systems, and those that do exist have investigated boiling on plain surfaces only. In water-glycol systems, water is the light component, which makes these systems unique compared to those that have been previously examined. This report examines several water-glycol systems, and documents a database of experimental heat transfer coefficients for these systems. In addition, this investigation also examines the effect of an enhanced surface on pool boiling in water-glycol mixtures, by comparing boiling on a smooth surface to boiling on a Turbo IIIB. The experimental apparatus, test sections, and the experimental procedures are described. The mixture systems tested included water-propylene glycol, water-ethylene glycol, and water-diethylene glycol. All experimental data were obtained at atmospheric pressure with the test section oriented horizontally. The effect of subcooling in pool boiling of mixtures is another area that has received limited attention. Therefore, experimental data were obtained for the water-propylene glycol and water-ethylene glycol systems for subcoolings ranging from 0 to 30 C. The experimental data showed that boiling heat transfer coefficients were found to have significant degradation due to the mixture effect for each of the water-glycol systems examined. This result is consistent with previous studies which examined water-hydrocarbon mixtures with large boiling ranges. The Turbo BIII surface was found to significantly increase heat transfer in each mixture and pure component in comparison to that for the smooth surface.

Stephen M Bajorek; J. Schnelle

2002-05-01T23:59:59.000Z

384

Homes show greatest seasonal variation in electricity use - Today ...  

U.S. Energy Information Administration (EIA)

Tools; Glossary › All Reports ... Electricity use varies with the weather, as changes in temperature and humidity affect the demand for space heating and cooling.

385

Fuel Cycle and Isotopes Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Divisions Fuel Cycle and Isotopes Division Jeffrey Binder, Division Director Jeffrey Binder, Division Director The Fuel Cycle and Isotopes Division (FCID) of the Nuclear Science...

386

ABSORPTION HEAT PUMP IN THE DISTRICT HEATING  

E-Print Network (OSTI)

#12;ABSORPTION HEAT PUMP IN THE DISTRICT HEATING PLANT Dr.sc.ing. Agnese Lickrastina M.Sc. Normunds European Heat Pump Summit 2013, Nuremberg, 15-16.10.2013 · Riga District Heating company · Operation #12;JSC RGAS SILTUMS · the biggest District Heating company in Latvia and in the Baltic states

Oak Ridge National Laboratory

387

Heat Exchangers  

Science Conference Proceedings (OSTI)

Table 16   Ceramic heat exchanger systems...Soaking pit 870â??1230 1600â??2250 Fe, Si, alkalis Solar Turbines â?¦ 4â??8 OD Ã? 180 long (440 tubes) Aluminum melt furnaces 1010 1850 Alkali salts Plate fin GTE 0.6, 1.6 25â??46 Multiple 870â??1370 1600â??2250 Clean (good), alkalis (poor) Coors 0.25, 1.0 30 Ã? 30 Ã? 46 Multiple Clean (good), alkalis (poor) Radiant...

388

"Integrated Gasification Combined Cycle"  

U.S. Energy Information Administration (EIA) Indexed Site

Status of technologies and components modeled by EIA" Status of technologies and components modeled by EIA" ,"Revolutionary","Evolutionary","Mature" "Pulverized Coal",,,"X" "Pulverized Coal with CCS" " - Non-CCS portion of Pulverized Coal Plant",,,"X" " - CCS","X" "Integrated Gasification Combined Cycle" " - Advanced Combustion Turbine",,"X" " - Heat Recovery Steam Generator",,,"X" " - Gasifier",,"X" " - Balance of Plant",,,"X" "Conventional Natural Gas Combined Cycle" " - Conventional Combustion Turbine",,,"X" " - Heat Recovery Steam Generator",,,"X" " - Balance of Plant",,,"X"

389

Heat extraction from salinity-gradient solar ponds using heat pipe heat exchangers  

Science Conference Proceedings (OSTI)

This paper presents the results of experimental and theoretical analysis on the heat extraction process from solar pond by using the heat pipe heat exchanger. In order to conduct research work, a small scale experimental solar pond with an area of 7.0 m{sup 2} and a depth of 1.5 m was built at Khon Kaen in North-Eastern Thailand (16 27'N102 E). Heat was successfully extracted from the lower convective zone (LCZ) of the solar pond by using a heat pipe heat exchanger made from 60 copper tubes with 21 mm inside diameter and 22 mm outside diameter. The length of the evaporator and condenser section was 800 mm and 200 mm respectively. R134a was used as the heat transfer fluid in the experiment. The theoretical model was formulated for the solar pond heat extraction on the basis of the energy conservation equations and by using the solar radiation data for the above location. Numerical methods were used to solve the modeling equations. In the analysis, the performance of heat exchanger is investigated by varying the velocity of inlet air used to extract heat from the condenser end of the heat pipe heat exchanger (HPHE). Air velocity was found to have a significant influence on the effectiveness of heat pipe heat exchanger. In the present investigation, there was an increase in effectiveness by 43% as the air velocity was decreased from 5 m/s to 1 m/s. The results obtained from the theoretical model showed good agreement with the experimental data. (author)

Tundee, Sura; Terdtoon, Pradit; Sakulchangsatjatai, Phrut [Department of Mechanical Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200 (Thailand); Singh, Randeep; Akbarzadeh, Aliakbar [Energy Conservation and Renewable Energy Group, School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University, Bundoora East Campus, Bundoora, Victoria 3083 (Australia)

2010-09-15T23:59:59.000Z

390

Electrically heated liquid tank employing heat pipe heat transfer means  

SciTech Connect

The heating apparatus for applying heat to the interior of a chamber includes a modular, removable, electrical, heat-producing unit and a heat pipe mountable in a wall of the chamber with one end of the pipe arranged to receive heat from the electrical heat producing unit exterior of the housing and with another end of the pipe constructed and arranged to apply heat to the medium within the chamber. The heat pipe has high conductivity with a low temperature differential between the ends thereof and the heat producing unit includes an electric coil positioned about and removably secured to the one end of the heat pipe. The electric coil is embedded in a high thermal conducitivity, low electrical conductivity filler material which is surrounded by a low thermal conductivity insulating jacket and which is received around a metal core member which is removably secured to the one end of the heat pipe.

Shutt, J.R.

1978-12-26T23:59:59.000Z

391

Solar heat collector  

SciTech Connect

A solar heat collector comprises an evacuated transparent pipe; a solar heat collection plate disposed in the transparent pipe; a heat pipe, disposed in the transparent pipe so as to contact with the solar heat collection plate, and containing an evaporable working liquid therein; a heat medium pipe containing a heat medium to be heated; a heat releasing member extending along the axis of the heat medium pipe and having thin fin portions extending from the axis to the inner surface of the heat medium pipe; and a cylindrical casing surrounding coaxially the heat medium pipe to provide an annular space which communicates with the heat pipe. The evaporable working liquid evaporates, receiving solar heat collected by the heat collection plate. The resultant vapor heats the heat medium through the heat medium pipe and the heat releasing member.

Yamamoto, T.; Imani, K.; Sumida, I.; Tsukamoto, M.; Watahiki, N.

1984-04-03T23:59:59.000Z

392

Development of a Direct Evaporator for the Organic Rankine Cycle  

Science Conference Proceedings (OSTI)

This paper describes research and development currently underway to place the evaporator of an Organic Rankine Cycle (ORC) system directly in the path of a hot exhaust stream produced by a gas turbine engine. The main goal of this research effort is to improve cycle efficiency and cost by eliminating the usual secondary heat transfer loop. The project’s technical objective is to eliminate the pumps, heat exchangers and all other added cost and complexity of the secondary loop by developing an evaporator that resides in the waste heat stream, yet virtually eliminates the risk of a working fluid leakage into the gaseous exhaust stream. The research team comprised of Idaho National Laboratory and General Electric Company engineers leverages previous research in advanced ORC technology to develop a new direct evaporator design that will reduce the ORC system cost by up to 15%, enabling the rapid adoption of ORCs for waste heat recovery.

Donna Post Guillen; Helge Klockow; Matthew Lehar; Sebastian Freund; Jennifer Jackson

2011-02-01T23:59:59.000Z

393

Optimum Heat Power Cycles for Process Industrial Plants  

E-Print Network (OSTI)

Electric power cogeneration is compared with direct mechanical drives emphasizing the technical aspects having the greatest impact on energy economics. Both steam and gas turbine applications are discussed and practical methods of developing existing systems for maximum effectiveness are explained. Specific plant cases are cited as examples of major dollar savings opportunities.

Waterland, A. F.

1982-01-01T23:59:59.000Z

394

MINIATURIZATION OF AN AMMONIA-WATER ABSORPTION CYCLE HEAT PUMP ...  

solution, and the subsequent gas-liquid mixture was separated down stream in a gravity separator vessel. Initial open-loop testing of components and ...

395

Brayton-cycle solvent recovery heat pump. A technical brief  

SciTech Connect

The US Department of Energy`s (DOE`s) Office of Industrial Technologies (OIT) sponsors research and development (R & D) to improve the energy efficiency of American industry and to provide for fuel flexibility. Working closely with industry, OIT has successfully developed more than 50 new technologies that saved industry approximately 80 trillion Btu (84 quadrillion joules) of energy in 1992. More than 200 other projects are in various stages of development from laboratory research to field tests. The use of solvents in the industrial sector is widespread and results in the emission of volatile organic compounds (VOCs) to the atmosphere. These VOC emissions represent an economic loss to industry and contribute significantly to air pollution. To comply with increasingly strict environmental regulations while keeping costs down, industry must find efficient and cost-effective ways to control emissions from solvent use.

Not Available

1994-11-01T23:59:59.000Z

396

Geothermal district heating systems  

DOE Green Energy (OSTI)

Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

Budney, G.S.; Childs, F.

1982-01-01T23:59:59.000Z

397

Helium process cycle  

DOE Patents (OSTI)

A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

Ganni, Venkatarao (Yorktown, VA)

2007-10-09T23:59:59.000Z

398

Helium process cycle  

SciTech Connect

A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

Ganni, Venkatarao (Yorktown, VA)

2007-10-09T23:59:59.000Z

399

Helium process cycle  

DOE Patents (OSTI)

A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

Ganni, Venkatarao (Yorktown, VA)

2008-08-12T23:59:59.000Z

400

Status report on survey of alternative heat pumping technologies  

SciTech Connect

The Department of Energy is studying alternative heat pumping technologies to identify possible cost effective alternatives to electric driven vapor compression heat pumps, air conditioners, and chillers that could help reduce CO{sub 2} emissions. Over thirty different technologies are being considered including: engine driven systems, fuel cell powered systems, and alternative cycles. Results presented include theoretical efficiencies for all systems as well as measured performance of some commercial, prototype, or experimental systems. Theoretical efficiencies show that the alternative electric-driven technologies would have HSPFs between 4 and 8 Btu/Wh (1.2 to 2.3 W/W) and SEERs between 3 and 9.5 Btu/Wh (0.9 and 2.8 W/W). Gas-fired heat pump technologies have theoretical seasonal heating gCOPs from 1.1 to 1.7 and cooling gCOPs from 0.95 to 1.6 (a SEER 12 Btu/Wh electric air conditioner has a primary energy efficiency of approximately 1.4 W/W).

Fischer, S.

1998-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

NREL: Energy Analysis - Concentrating Solar Power Results - Life Cycle  

NLE Websites -- All DOE Office Websites (Extended Search)

Concentrating Solar Power Results - Life Cycle Assessment Harmonization Concentrating Solar Power Results - Life Cycle Assessment Harmonization Life Cycle Greenhouse Gas Emissions from Concentrating Solar Power (Factsheet) Cover of the Life Cycle Greenhouse Gas Emissions from Concentrating Solar Power Download the Factsheet Flowchart that shows the life cycle stages for concentrating solar power systems. For help reading this chart, please contact the webmaster. Figure 1. Process flow diagram illustrating the life cycle stages for concentrating solar power (CSP) systems. The yellow box defined by the grey line shows the systems boundaries assumed in harmonization. Enlarge image NREL developed and applied a systematic approach to review literature on life cycle assessments of concentrating solar power (CSP) systems, identify

402

Energy Basics: Radiant Heating  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

very low heat capacity and have the quickest response time of any heating technology. More Information Visit the Energy Saver website for more information about radiant heating...

403

Energy Basics: Radiant Heating  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

low heat capacity and have the quickest response time of any heating technology. More Information Visit the Energy Saver website for more information about radiant heating in homes...

404

Technology for Brayton-cycle space powerplants using solar and nuclear energy  

SciTech Connect

Brayton-cycle gas turbines have the potential to use either solar heat or nuclear reactors to generate from tens of kilowatts to tens of megawatts of power in space, all this from a single technology for the power-generating system. Their development for solar-energy dynamic power generation for the space station could be the first step in an evolution of such powerplants for a very wide range of applications. At the low power level of only 10 kWe, a power-generating system has already demonstrated overall efficiency of 0.29 and operated for 38,000 hr. Tests of improved components show that, if installed in the power-generating system, these components would raise that efficiency to 0.32; this efficiency is twice that so far demonstrated by any alternate concept, a characteristic especially important for solar power systems. Because of this high efficiency, solar-heat Brayton-cycle power generators offer the potential to increase power per unit of solar-collector area to levels exceeding four times that from photovoltaic powerplants based on present technology for silicon solar cells. For the heat source, paraboloidal mirrors have been assembled from sectors here on Earth. One mirror, 1.5-m diameter, had a standard error for its surface of only 1 arc-min and a specific mass of only 1.3 kg/m 2. A heavier mirror (nearly 5 kg/m{sup 2}), assembled from 12 sectors, had a standard surface error of 3 arc-min but was 6 m in diameter. Either of these mirrors is sufficiently accurate for use with the Brayton cycle, but the techniques for actually assembling large mirrors in space must yet be worked out. For use during the shadow period of a low Earth orbit (LEO), heat could be stored in LiF, a salt that melts at 1121 K (1558{degrees}F) and whose latent heat of fusion exceeds 1 MJ/kg. Because of the prior experience with its fabrication and of its tolerance of the thermal cycling in LEO, Nb-1Zr was selected to contain the LiF.

English, R.E.

1986-02-01T23:59:59.000Z

405

New Regenerative Cycle for Vapor Compression Refrigeration  

SciTech Connect

The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and second step of compression. In the proposed system, the compressor compresses the vapor only to 50-60% of the final pressure, while the additional compression is provided by a jet device using internal potential energy of the working fluid flow. Therefore, the amount of mechanical energy required by a compressor is significantly reduced, resulting in the increase of efficiency (either COP or EER). The novelty of the cycle is in the equipment and in the way the multi-staging is accomplished. The anticipated result will be a new refrigeration system that requires less energy to accomplish a cooling task. The application of this technology will be for more efficient designs of: (1) Industrial chillers, (2) Refrigeration plants, (3) Heat pumps, (4) Gas Liquefaction plants, (5) Cryogenic systems.

Mark J. Bergander

2005-08-29T23:59:59.000Z

406

Power Plant Cycling Costs  

NLE Websites -- All DOE Office Websites (Extended Search)

Power Plant Cycling Costs Power Plant Cycling Costs April 2012 N. Kumar, P. Besuner, S. Lefton, D. Agan, and D. Hilleman Intertek APTECH Sunnyvale, California NREL Technical Monitor: Debra Lew Subcontract Report NREL/SR-5500-55433 July 2012 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401 303-275-3000 * www.nrel.gov Contract No. DE-AC36-08GO28308 Power Plant Cycling Costs April 2012 N. Kumar, P. Besuner, S. Lefton, D. Agan, and D. Hilleman Intertek APTECH Sunnyvale, California NREL Technical Monitor: Debra Lew Prepared under Subcontract No. NFT-1-11325-01

407

Impact of Geoengineering Schemes on the Global Hydrological Cycle  

SciTech Connect

The rapidly rising CO{sub 2} level in the atmosphere has led to proposals of climate stabilization via 'Geoengineering' schemes that would mitigate climate change by intentionally reducing the solar radiation incident on earth's surface. In this paper, we address the impact of these climate stabilization schemes on the global hydrological cycle, using equilibrium simulations from an atmospheric general circulation model coupled to a slab ocean model. We show that insolation reductions sufficient to offset global-scale temperature increases lead to a decrease in the intensity of the global hydrologic cycle. This occurs because solar forcing is more effective in driving changes in global mean evaporation than is CO{sub 2} forcing of a similar magnitude. In the model used here, the hydrologic sensitivity, defined as the percentage change in global mean precipitation per degree warming, is 2.4% for solar forcing, but only 1.5% for CO{sub 2} forcing. Although other models and the climate system itself may differ quantitatively from this result, the conclusion can be understood based on simple considerations of the surface energy budget and thus is likely to be robust. Compared to changing temperature by altering greenhouse gas concentrations, changing temperature by varying insolation results in larger changes in net radiative fluxes at the surface; these are compensated by larger changes in latent and sensible heat fluxes. Hence the hydrological cycle is more sensitive to temperature adjustment via changes in insolation than changes in greenhouse gases. This implies that an alteration in solar forcing might offset temperature changes or hydrological changes from greenhouse warming, but could not cancel both at once.

Bala, G; Duffy, P; Taylor, K

2007-12-07T23:59:59.000Z

408

Heat transfer and heat exchangers reference handbook  

Science Conference Proceedings (OSTI)

The purpose of this handbook is to provide Rocky Flats personnel with an understanding of the basic concepts of heat transfer and the operation of heat exchangers.

Not Available

1991-01-15T23:59:59.000Z

409

Heating systems for heating subsurface formations  

Science Conference Proceedings (OSTI)

Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

Nguyen, Scott Vinh (Houston, TX); Vinegar, Harold J. (Bellaire, TX)

2011-04-26T23:59:59.000Z

410

Gas Turbine Technology, Part A: Overview, Cycles, and Thermodynamic Performance  

E-Print Network (OSTI)

The growth of cogeneration technology has accelerated in recent years, and it is estimated that fifty percent of the cogeneration market will involve gas turbines. To several energy engineers, gas turbine engines present a new and somewhat perplexing prime mover. This paper (Parts A & B) intends to treat the area of gas turbine technology to provide a broad overview and understanding of this subject. This paper (Part A) covers the basics of gas turbine cycles, thermodynamics and performance considerations that are important in cogeneration. Simple, regenerative and combined cycles will be discussed, along with important performance losses (inlet and exit losses and part load operation). Waste heat recovery, as it relates to gas turbine performance, will also be discussed. This paper will provide the basic equations enabling quick computations to be made. Topics such as typical efficiencies, evaporative cooling costs, emissions, etc. will be discussed. A brief discussion of advanced cycles such as the dual fluid cycle and close cycles is also made.

Meher-Homji, C. B.; Focke, A. B.

1985-05-01T23:59:59.000Z

411

Development of the Hybrid Sulfur Thermochemical Cycle  

DOE Green Energy (OSTI)

The production of hydrogen via the thermochemical splitting of water is being considered as a primary means for utilizing the heat from advanced nuclear reactors to provide fuel for a hydrogen economy. The Hybrid Sulfur (HyS) Process is one of the baseline candidates identified by the U.S. Department of Energy [1] for this purpose. The HyS Process is a two-step hybrid thermochemical cycle that only involves sulfur, oxygen and hydrogen compounds. Recent work has resulted in an improved process design with a calculated overall thermal efficiency (nuclear heat to hydrogen, higher heating value basis) approaching 50%. Economic analyses indicate that a nuclear hydrogen plant employing the HyS Process in conjunction with an advanced gas-cooled nuclear reactor system can produce hydrogen at competitive prices. Experimental work has begun on the sulfur dioxide depolarized electrolyzer, the major developmental component in the cycle. Proof-of-concept tests have established proton-exchange-membrane cells (a state-of-the-art technology) as a viable approach for conducting this reaction. This is expected to lead to more efficient and economical cell designs than were previously available. Considerable development and scale-up issues remain to be resolved, but the development of a viable commercial-scale HyS Process should be feasible in time to meet the commercialization schedule for Generation IV gas-cooled nuclear reactors.

Summers, William A.; Steimke, John L

2005-09-23T23:59:59.000Z

412

Separations Needs for the Alternate Chemical Cycles  

DOE Green Energy (OSTI)

The bulk of the efforts for the development of a hydrogen production plant supported by the Nuclear Hydrogen Initiative (NHI) have been directed towards the sulfur-iodine (S-I) thermochemical cycle. However, it was judged prudent to re-investigate alternate chemical cycles in light of new developments and technical accomplishments derived from the current S-I work. This work analyzes the available data for the promising alternate chemical cycles to provide an understanding of their inherent chemical separations needs. None of the cycles analyzed have separations that are potential “show stoppers”; although some of the indicated separations will be challenging to perform. The majority of the separations involve processes that are either more achievable or more developed

Frederick F. Stewart

2007-05-01T23:59:59.000Z

413

Regional business cycles in Italy  

Science Conference Proceedings (OSTI)

There is clear evidence for differences in the structure of the Italian regional business cycle in the period 1951-2004: the relationship with the national business cycle is closer in the North than in the South. The interaction between regional cycles ... Keywords: Regional business cycles, Spectral analysis, Stylized facts

Camilla Mastromarco; Ulrich Woitek

2007-10-01T23:59:59.000Z

414

Heat exchanger  

DOE Patents (OSTI)

A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

Brackenbury, Phillip J. (Richland, WA)

1986-01-01T23:59:59.000Z

415

Indirect-fired gas turbine dual fuel cell power cycle  

DOE Patents (OSTI)

A fuel cell and gas turbine combined cycle system which includes dual fuel cell cycles combined with a gas turbine cycle wherein a solid oxide fuel cell cycle operated at a pressure of between 6 to 15 atms tops the turbine cycle and is used to produce CO.sub.2 for a molten carbonate fuel cell cycle which bottoms the turbine and is operated at essentially atmospheric pressure. A high pressure combustor is used to combust the excess fuel from the topping fuel cell cycle to further heat the pressurized gas driving the turbine. A low pressure combustor is used to combust the excess fuel from the bottoming fuel cell to reheat the gas stream passing out of the turbine which is used to preheat the pressurized air stream entering the topping fuel cell before passing into the bottoming fuel cell cathode. The CO.sub.2 generated in the solid oxide fuel cell cycle cascades through the system to the molten carbonate fuel cell cycle cathode.

Micheli, Paul L. (Sacramento, CA); Williams, Mark C. (Morgantown, WV); Sudhoff, Frederick A. (Morgantown, WV)

1996-01-01T23:59:59.000Z

416

Answering Key Fuel Cycle Questions  

Science Conference Proceedings (OSTI)

The Advanced Fuel Cycle Initiative (AFCI) program has both “outcome” and “process” goals because it must address both waste already accumulating as well as completing the fuel cycle in connection with advanced nuclear power plant concepts. The outcome objectives are waste geological repository capacity and cost, energy security and sustainability, proliferation resistance, fuel cycle economics, and safety. The process objectives are readiness to proceed and adaptability and robustness in the face of uncertainties. A classic decision-making approach to such a multi-attribute problem would be to weight individual quantified criteria and calculate an overall figure of merit. This is inappropriate for several reasons. First, the goals are not independent. Second, the importance of different goals varies among stakeholders. Third, the importance of different goals is likely to vary with time, especially the “energy future.” Fourth, some key considerations are not easily or meaningfully quantifiable at present. Instead, at this point, we have developed 16 questions the AFCI program should answer and suggest an approach of determining for each whether relevant options improve meeting each of the program goals. We find that it is not always clear which option is best for a specific question and specific goal; this helps identify key issues for future work. In general, we suggest attempting to create as many win-win decisions (options that are attractive or neutral to most goals) as possible. Thus, to help clarify why the program is exploring the options it is, and to set the stage for future narrowing of options, we have developed 16 questions, as follows: · What are the AFCI program goals? · Which potential waste disposition approaches do we plan for? · What are the major separations, transmutation, and fuel options? · How do we address proliferation resistance? · Which potential energy futures do we plan for? · What potential external triggers do we plan for? · Should we separate uranium? · If we separate uranium, should we recycle it, store it or dispose of it? · Is it practical to plan to fabricate and handle “hot” fuel? · Which transuranic elements (TRU) should be separated and transmuted? · Of those TRU separated, which should be transmuted together? · Should we separate and/or transmute Cs and Sr isotopes that dominate near-term repository heating? · Should we separate and/or transmute very long-lived Tc and I isotopes? · Which separation technology? · What mix of transmutation technologies? · What fuel technology best supports the above decisions?

Steven J. Piet; Brent W. Dixon; J. Stephen Herring; David E. Shropshire; Mary Lou Dunzik-Gougar

2003-10-01T23:59:59.000Z

417

Radiofrequency plasma heating: proceedings  

SciTech Connect

The conference proceedings include sessions on Alfven Wave Heating, ICRF Heating and Current Drive, Lower Hybrid Heating and Current Drive, and ECRF Heating. Questions of confinement, diagnostics, instabilities and technology are considered. Individual papers are cataloged separately. (WRF)

Swenson, D.G. (ed.)

1985-01-01T23:59:59.000Z

418

Electrically heated DPF start-up strategy  

SciTech Connect

An exhaust system that processes exhaust generated by an engine has a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates in the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates. Heat generated by combustion of particulates in the heater induces combustion of particulates within the DPF. A control module selectively enables current flow to the electrical heater for an initial period of a DPF regeneration cycle, and limits exhaust flow while the electrical heater is heating to a predetermined soot combustion temperature.

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2012-04-10T23:59:59.000Z

419

Thulium heat sources for space power applications  

DOE Green Energy (OSTI)

Reliable power supplies for use in transportation and remote systems will be an important part of space exploration terrestrial activities. A potential power source is available in the rare earth metal, thulium. Fuel sources can be produced by activating Tm-169 targets in the space station reactor. The resulting Tm-170 heat sources can be used in thermoelectric generators to power instrumentation and telecommunications located at remote sites such as weather stations. As the heat source in a dynamic Sterling or Brayton cycle system, the heat source can provide a lightweight power source for rovers or other terrestrial transportation systems.

Alderman, C.J.

1992-05-01T23:59:59.000Z

420

MGCR HEAT EXCHANGER TEST PROGRAM. Final Report  

SciTech Connect

The Maritime Gas-cooled Reactor (MGCR) project has conipleted the study and design of a closed-cycle gasturbine propulsion plant utilizing a helium- cooled nuclear reactor as the heat source. The cycle employs a counterflow shell- and-tube regenerator to attain a high thermodynamic cycle efficiency. A heat exchanger test program was conducted to compile and correlate sufficient experimental data for the aerodynamic and thermal design of the prototype regenerator. The model heat exchanger was similar in configaration to the prototype unit. The pressure-drop and heat-transfer performance of a compact parallel-flow tube bundle is given hoth in the unsupported configuration and with airfoil-shaped tube supports distributed along the bundle. The Fanning friction factor with the airfoil-shaped supports is approximately 70% greater than for the unsupported tube configuration. The airfoil supports effect a 40% increase in Colburn's heat transfer factor, j, over the unsupported configuration. Determinations of the unsupported-tube values of friction factor and Colburn-j agreed well with the literature. A section is devoted to the application of these data to the design of exchangers. The correlated data, representing some 1200 individual runs, cover a range of Reynolds number from 10,000 to 500,000. The moderate pressure-drop increment due to the airfoil-shaped supports, in conjunction with the favorable increase in heat-transfer rate, becomes especially important in the design of compact gas-to-gas heat exchangers with very low friction pressure losses. The concluding section of the report compares the size, weight, and cost of conventional baffled-shell units and the MGCR design for the requirements of the MGCR cycle. The MGCR design was one-fifth the volume, one-fourth the weight, and one-third the cost of comparable baffled-shell units. (auth)

Paulson, H.C. II

1961-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Electronic thermostat with selectable mode to control heating only, cooling only or both heating and cooling  

Science Conference Proceedings (OSTI)

This patent describes a thermostat for use in a building having means for cooling the building and means for heating the building, the thermostat being connected to the cooling means and the heating means and operative to generate an energizing signal for only one of the heating means or cooling means at a given time, the thermostat comprising: means for measuring the ambient temperature within the building; manual data entry means; means for storing a program of desired heating temperatures over a repetitive time cycle, programmed by the manual data entry means; a clock operative to generate time signals within the repetitive time cycle; means for generating a signal representative of a desired heating temperature and a desired cooling temperature at the present time based upon the signals from the clock in the stored temperature program; means for placing the thermostat in either a first mode where control signals are generated only for the heating means as a function of the difference between the measured temperature within the building and the desired heating temperature signal. Control signals are generated for either the heating means or the cooling means based upon the measured temperature and the respective desired heating and cooling temperature signals.

Levine, M.R.

1987-08-04T23:59:59.000Z

422

Geothermal direct contact heat exchange. Final report  

DOE Green Energy (OSTI)

A glass direct contact heat exchange column was operated in the laboratory. The column was operated at atmospheric pressure using hot water and normal hexane. Column internals testing included an empty column, sieve trays, disk-and-doughnut trays, and two types of packing. Operation was very smooth in all cases and the minimum temperature approaches varied from less than 1/sup 0/C for packing to 13/sup 0/C for the empty column. High heat transfer rates were obtained in all cases, however, columns should be sized on the basis of liquid and vapor traffic. The solubilities of hydrocarbons were determined for normal hexane, pentane and butane in water and sodium chloride and calcium chloride brines at various temperatures. The values seem to be internally consistent and salt content was found to depress hydrocarbon solubility. Laboratory stripping tests showed that gas stripping can be used to remove hydrocarbon from reject hot water from the direct contact heat exchange column. Although the gas volumes required are small, stripping gas requirements cannot be accurately predicted without testing. A computer program was used to study the effect of operating variables on the thermodynamic cycle efficiencies. Optimum efficiencies for the moderate brine conditions studied were obtained with isopentane as working fluid and relatively low operating pressure. A preliminary design for a 50 MWe plant was prepared and plant capital cost and operating cost were estimated. These costs were combined with previously developed brine production and power transmission costs to provide an estimate of the cost of delivered power for a geothermal field at Heber, California. A pilot plant program is described that would be suitable for continuing the investigation of the direct contact process in the field. The program includes a suggested schedule and the estimated cost.

Sims, A.V.

1977-06-10T23:59:59.000Z

423

Testing of a sodium heat pipe  

SciTech Connect

The operation of a heat pipe with both thermal radiation and convection heat rejection has been experimentally examined. The thermal radiation heat rejection conditions are similar to those which would be experienced in a space environment. The experimental results show good agreement with the analytical model. 3 refs., 2 figs.

Holtz, R.E.

1991-01-01T23:59:59.000Z

424

Comparison of Geothermal Power Conversion Cycles  

SciTech Connect

Geothermal power conversion cycles are compared with respect to recovery of the available wellhead power. The cycles compared are flash steam, in which steam turbines are driven by steam separated from one or more flash states; binary, in which heat is transferred from flashed steam to an organic turbine cycle; and dual steam, in which two-phase expanders are driven by the flashing steam-brine mixture and steam turbines by the separated steam. Expander efficiencies assumed are 0.7 for steam turbines, 0.8 for organic turbines, and 0.6 for two-phase expanders. The fraction of available wellhead power delivered by each cycle is found to be about the same at all brine temperatures: 0.65 with one stage and 0.7 with four stages for dual stream; 0.4 with one stage and 0.6 with four stages for flash steam; 0.5 for binary; and 0.3 with one stage and 0.5 with four stages for flash binary.

Elliott, David G.

1976-12-01T23:59:59.000Z

425

Immobilization of Fast Reactor First Cycle Raffinate  

Science Conference Proceedings (OSTI)

This paper describes the results of work to bring forward the timing for the immobilization of first cycle raffinate from reprocessing fuel from the Dounreay Prototype Fast Reactor (PFR). First cycle raffinate is the liquor which contains > 99% of the fission products separated from spent fuel during reprocessing. Approximately 203 m3 of raffinate from the reprocessing of PFR fuel is held in four tanks at the UKAEA's site at Dounreay, Scotland. Two methods of immobilization of this high level waste (HLW) have been considered: vitrification and cementation. Vitrification is the standard industry practice for the immobilization of first cycle raffinate, and many papers have been presented on this technique elsewhere. However, cementation is potentially feasible for immobilizing first cycle raffinate because the heat output is an order of magnitude lower than typical HLW from commercial reprocessing operations such as that at the Sellafield site in Cumbria, England. In fact, it falls within the upper end of the UK definition of intermediate level waste (ILW). Although the decision on which immobilization technique will be employed has yet to be made, initial development work has been undertaken to identify a suitable cementation formulation using inactive simulant of the raffinate. An approach has been made to the waste disposal company Nirex to consider the disposability of the cemented product material. The paper concentrates on the process development work that is being undertaken on cementation to inform the decision making process for selection of the immobilization method.

Langley, K. F.; Partridge, B. A.; Wise, M.

2003-02-26T23:59:59.000Z

426

Photovoltaic roof heat flux  

E-Print Network (OSTI)

and could the heat transfer processes be modeled to estimateindicating that the heat transfer processes were modeled w i

Samady, Mezhgan Frishta

2011-01-01T23:59:59.000Z

427

Closed cycle cogeneration for the future  

Science Conference Proceedings (OSTI)

While present energy needs can be met with available supplies of fossil fuels, the need to plan for the eventual elimination of dependence on premium fuels in utility and industrial applications remains urgent. One of the most promising power conversion technologies for these needs is the closed cycle gas turbine (CCGT) configured for power and heat production. Closed cycle gas turbines have been in commercial use, principally in Europe, for over four decades. That experience base, combined with emerging awareness of potential CCGT applications, could lead to the operation of coal-fired CCGT cogeneration systems in the U.S. within the next decade. This paper discusses the multi-fuel capability of the CCGT and compares its performance as a flexible cogeneration system with that of a more conventional steam turbine system.

Crim, W.M.; Fraize, W.E.; Kinney, G.; Malone, G.A.

1984-06-01T23:59:59.000Z

428

New and Underutilized Technology: Solar Water Heating | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Solar Water Heating Solar Water Heating New and Underutilized Technology: Solar Water Heating October 7, 2013 - 9:02am Addthis The following information outlines key deployment considerations for solar water heating within the Federal sector. Benefits Solar water heating uses solar thermal collectors to heat water. Application Solar water heating is applicable in most building categories. Climate and Regional Considerations Solar water heating is best in regions with high insolation. Key Factors for Deployment The Energy Independence and Security Act (EISA) of 2007 requires 30% of hot water demand in new Federal buildings and major renovations to be met with solar water heating equipment providing it is life-cycle cost effective. Federal agencies must consider collector placement location to optimize

429

Heat-pump desuperheaters for supplying domestic hot water - estimation of energy savings and economic viability for residential applications  

SciTech Connect

The heat reclaimer is a double-wall heat exchange system that removes superheat from the heat pump (or central air conditioning) cycle and uses it to heat water for domestic uses. During summer operation, this heat would normally be rejected to the atmosphere without being used. Thus, water heating is accomplished using essentially no primary fuel. In winter, the heat extracted from the cycle would have been used for space heating. However, energy savings are possible above the heat pump balance point because water heating is performed at an enhanced efficiency. Potential energy savings and economic viability of the heat reclaimer were determined for 28 sites throughout the United States. These results indicate that the heat reclaimer is not economically attractive compared with gas- or oil-fired water heating systems. However, it is competitive with electric resistance water heaters. Based on these results, a calculational scheme has been developed that could be integrated into the model audit procedure.

Olszewski, M.; Fontana, E.C.

1983-05-01T23:59:59.000Z

430

Interannual Variability of Indian Ocean Heat Transport  

Science Conference Proceedings (OSTI)

The work in this paper builds upon the relatively well-studied seasonal cycle of the Indian Ocean heat transport by investigating its interannual variability over a 41-yr period (1958–98). An intermediate, two-and-a-half-layer thermodynamically ...

Galina Chirokova; Peter J. Webster

2006-03-01T23:59:59.000Z

431

Heat pipe methanator  

DOE Patents (OSTI)

A heat pipe methanator for converting coal gas to methane. Gravity return heat pipes are employed to remove the heat of reaction from the methanation promoting catalyst, transmitting a portion of this heat to an incoming gas pre-heat section and delivering the remainder to a steam generating heat exchanger.

Ranken, William A. (Los Alamos, NM); Kemme, Joseph E. (Los Alamos, NM)

1976-07-27T23:59:59.000Z

432

Backstage at the Daily Show | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Energy 101: Solar PV Sec. Chu Online Town Hall Energy 101: Cool Roofs Energy 101: Geothermal Heat Pumps Why Cool Roofs? Chu at COP-16: Building a Sustainable Energy Future...

433

Combined Cycles and Cogeneration - An Alternative for the Process Industries  

E-Print Network (OSTI)

Cogeneration may be described as an efficient method for the production of electric power sequentially with process steam or heat which optimizes the energy supplied as fuel to maximize the energy produced for consumption. The state-of-the-art combined cycle system consisting of combustion turbines, heat recovery steam generators, and steam turbine-generator units, offers a high efficiency method for the production of electrical and heat energy at relatively low installed and operating costs. This paper describes the various aspects of cogeneration in a manner which will illustrate the energy saving potential available utilizing proven technology.

Harkins, H. L.

1981-01-01T23:59:59.000Z

434

Seasonal Variation of Baroclinic Geostrophic Heat Transport: Is It Resolved by Existing Climatologies of the Atlantic Ocean?  

Science Conference Proceedings (OSTI)

Seasonal cycles of baroclinic geostrophic heat transport are systematically computed between 30°S and 40°N in the Atlantic from several hydrographic climatologies. The intercomparison of the cycles reveals very significant differences in both ...

S. Wacongne; L. Crosnier

2002-01-01T23:59:59.000Z

435

Surface Heat Balance in the Equatorial Pacific Ocean: Climatology and the Warming Event of 1994–95  

Science Conference Proceedings (OSTI)

The surface heat budget in the equatorial Pacific Ocean was investigated through ocean model simulations, both the climatological cycle and the case of the 1994–95 warm event. The dominant processes governing the seasonal cycle of sea surface ...

Anna Borovikov; Michele M. Rienecker; Paul S. Schopf

2001-06-01T23:59:59.000Z

436

Segmented heat exchanger  

DOE Patents (OSTI)

A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

Baldwin, Darryl Dean (Lafayette, IN); Willi, Martin Leo (Dunlap, IL); Fiveland, Scott Byron (Metamara, IL); Timmons, Kristine Ann (Chillicothe, IL)

2010-12-14T23:59:59.000Z

437

Dual source heat pump  

DOE Patents (OSTI)

What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

Ecker, Amir L. (Dallas, TX); Pietsch, Joseph A. (Dallas, TX)

1982-01-01T23:59:59.000Z

438

Heat reclaimer for a heat pump  

Science Conference Proceedings (OSTI)

This invention relates to a heat reclaiming device for a heat pump. The heat reclaimer is able to absorb heat from the compressor by circulating cooling fluid through a circuit which is mounted in good heat transfer relationship with the condenser, then around the shell of the motor-compressor and lastly around the hollow tube which connects the condenser to the compressor. The reclaiming circuit is connected into a fluid circulating loop which is used to supply heat to the evaporator coil of the heat pump.

Beacham, W.H.

1981-02-03T23:59:59.000Z

439

Configuration and performance of fuel cell-combined cycle options  

DOE Green Energy (OSTI)

The natural gas, indirect-fired, carbonate fuel-cell-bottomed, combined cycle (NG-IFCFC) and the topping natural-gas/solid-oxide fuel-cell combined cycle (NG-SOFCCC) are introduced as novel power-plant systems for the distributed power and on-site markets in the 20-200 mega-watt (MW) size range. The novel NG-IFCFC power-plant system configures the ambient pressure molten-carbonate fuel cell (MCFC) with a gas turbine, air compressor, combustor, and ceramic heat exchanger: The topping solid-oxide fuel-cell (SOFC) combined cycle is not new. The purpose of combining a gas turbine with a fuel cell was to inject pressurized air into a high-pressure fuel cell and to reduce the size, and thereby, to reduce the cost of the fuel cell. Today, the SOFC remains pressurized, but excess chemical energy is combusted and the thermal energy is utilized by the Carnot cycle heat engine to complete the system. ASPEN performance results indicate efficiencies and heat rates for the NG-IFCFC or NG-SOFCCC are better than conventional fuel cell or gas turbine steam-bottomed cycles, but with smaller and less expensive components. Fuel cell and gas turbine systems should not be viewed as competitors, but as an opportunity to expand to markets where neither gas turbines nor fuel cells alone would be commercially viable. Non-attainment areas are the most likely markets.

Rath, L.K.; Le, P.H.; Sudhoff, F.A.

1995-12-31T23:59:59.000Z

440

The Hybrid Sulfur Cycle for Nuclear Hydrogen Production  

DOE Green Energy (OSTI)

Two Sulfur-based cycles--the Sulfur-Iodine (SI) and the Hybrid Sulfur (HyS)--have emerged as the leading thermochemical water-splitting processes for producing hydrogen utilizing the heat from advanced nuclear reactors. Numerous international efforts have been underway for several years to develop the SI Cycle, but development of the HyS Cycle has lagged. The purpose of this paper is to discuss the background, current status, recent development results, and the future potential for this thermochemical process. Savannah River National Laboratory (SRNL) has been supported by the U.S. Department of Energy Office of Nuclear Energy, Science, and Technology since 2004 to evaluate and to conduct research and development for the HyS Cycle. Process design studies and flowsheet optimization have shown that an overall plant efficiency (based on nuclear heat converted to hydrogen product, higher heating value basis) of over 50% is possible with this cycle. Economic studies indicate that a nuclear hydrogen plant based on this process can be economically competitive, assuming that the key component, the sulfur dioxide-depolarized electrolyzer, can be successfully developed. SRNL has recently demonstrated the use of a proton-exchange-membrane electrochemical cell to perform this function, thus holding promise for economical and efficient hydrogen production.

Summers, William A.; Gorensek, Maximilian B.; Buckner, Melvin R.

2005-09-08T23:59:59.000Z

Note: This page contains sample records for the topic "heating cycle shows" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Solar Heat-Pipe Receiver Wick Modeling  

DOE Green Energy (OSTI)

Stirling-cycle engines have been identified as a promising technology for the conversion of concentrated solar energy into usable electrical power. In previous experimented work, we have demonstrated that a heat pipe receiver can significantly improve system performance-over a directly-illuminated heater head. The design and operating conditions of a heat pipe receiver differ significantly from typical laboratory heat pipes. New wick structures have been developed to exploit the characteristics of the solar generation system. Typically, these wick structures allow vapor generation within the wick. Conventional heat pipe models do not handle this enhancement yet it can more than double the performance of the wick. In this study, I develop a steady-state model of a boiling-enhanced wick for a solar heat pipe receiver. The model is used for design-point calculations and is written in FORTRAN90. Some limited comparisons have been made with actual test data.

Andraka, C.E.

1998-12-21T23:59:59.000Z

442

Life-Cycle Analysis and Energy Efficiency in State Buildings | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Life-Cycle Analysis and Energy Efficiency in State Buildings Life-Cycle Analysis and Energy Efficiency in State Buildings Life-Cycle Analysis and Energy Efficiency in State Buildings < Back Eligibility State Government Savings Category Heating & Cooling Commercial Heating & Cooling Cooling Home Weatherization Construction Commercial Weatherization Design & Remodeling Heating Appliances & Electronics Water Heating Bioenergy Manufacturing Buying & Making Electricity Alternative Fuel Vehicles Hydrogen & Fuel Cells Energy Sources Solar Water Wind Program Info State Missouri Program Type Energy Standards for Public Buildings Provider Office of Administration Several provisions of Missouri law govern energy efficiency in state facilities. In 1993 Missouri enacted legislation requiring life-cycle cost analysis for all new construction of state buildings and substantial

443

Oceanic Influences on the Seasonal Cycle in Evaporation over the Indian Ocean  

Science Conference Proceedings (OSTI)

The annual mean and seasonal cycle in latent heating over the Indian Ocean are investigated using a simple, analytical ocean model and a 3D, numerical, ocean model coupled to a prescribed atmosphere, which permits interaction through sea surface ...

Roxana C. Wajsowicz; Paul S. Schopf

2001-03-01T23:59:59.000Z

444

Stratospheric Temperature and Radiative Forcing Response to 11-Year Solar Cycle Changes in Irradiance and Ozone  

Science Conference Proceedings (OSTI)

The 11-yr solar cycle temperature response to spectrally resolved solar irradiance changes and associated ozone changes is calculated using a fixed dynamical heating (FDH) model. Imposed ozone changes are from satellite observations, in contrast ...

L. J. Gray; S. T. Rumbold; K. P. Shine

2009-08-01T23:59:59.000Z

445

Regional Residential Heating Oil Prices  

Gasoline and Diesel Fuel Update (EIA)

One of the first places where consumers are feeling the impact of One of the first places where consumers are feeling the impact of this winter's market pressures is in home heating oil prices. This chart shows prices through February 28, the most recent EIA data available. The general level of heating oil prices each year is largely a function of crude oil prices, and the price range over the course of the heatin