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Note: This page contains sample records for the topic "heating season performance" 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.


1

Radiant Barrier Performance during the Heating Season  

E-Print Network [OSTI]

in Combination with R-II and R-30 Ceiling Insulation." ORNLICON 239, Oak Ridge National Laboratory, Oak Ridge, TN. 13. Ober D.G. and Volckhausen T.W., 1988, "Radiant Barrier Insulation Performance in Full-Scale Attics with Soffit and Ridge Venting... in Combination with R-II and R-30 Ceiling Insulation." ORNLICON 239, Oak Ridge National Laboratory, Oak Ridge, TN. 13. Ober D.G. and Volckhausen T.W., 1988, "Radiant Barrier Insulation Performance in Full-Scale Attics with Soffit and Ridge Venting...

Medina, M. A.; O'Neal, D. L.; Turner, W. D.

2

Performance investigation of a solar heating system with underground seasonal energy storage for greenhouse application  

Science Journals Connector (OSTI)

Abstract This study reports the performance of a demonstrated 2304 m2 solar-heated greenhouse equipped with a seasonal thermal energy storage system in Shanghai, east China. This energy storage system utilises 4970 m3 of underground soil to store the heat captured by a 500 m2 solar collector in non-heating seasons through U-tube heat exchangers. During heating seasons, thermal energy is delivered by the heat exchange tubes placed on the plants shelves and the bare soil. The system can operate without a heat pump, which can save electricity consumption and further enhance the solar fraction. It was found that in the first operation year, 331.9 GJ was charged, and 208.9 GJ was later extracted for greenhouse space heating. No auxiliary heating equipment was installed so that solar energy covered all the heating loads directly or indirectly. It was demonstrated that this system was capable of maintaining an interior air temperature that was 13 °C higher than the ambient value when the latter temperature was ?2 °C at night. The ECOP (electrical coefficient of performance) of the first operation year was approximately 8.7, indicating a better performance than the common heat pump heating system.

J. Xu; Y. Li; R.Z. Wang; W. Liu

2014-01-01T23:59:59.000Z

3

Nebraska Preparing for the Upcoming Heating Season  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

Drivers * Crops Proactive Moves Heating Season Preparations by Nebraska Dealers * Contracting a bigger percentage of the amount of propane or heating oil that they estimate...

4

Propane: A Mid-heating Season Assessment  

Gasoline and Diesel Fuel Update (EIA)

9, 2001 9, 2001 Propane - A Mid-Heating Season Assessment by David Hinton and Alice Lippert, Petroleum Division, Office of Oil and Gas, Energy Information Administration In early October 2000, the Energy Information Administration (EIA) forecast that heating fuel markets would be expected to start the season with much higher prices and lower inventories than in recent years. While this assessment was true for both the heating oil and natural gas markets, propane markets actually began the season with adequate supplies but with high prices. Since EIA's forecast, propane inventories have plunged nearly 20 million barrels from their peak during the first half of the 2000-01 heating season while propane prices have continued to soar even higher than expected during this same period. This report will analyze some

5

Energy Efficient Integration of Heat Pumps into Solar District Heating Systems with Seasonal Thermal Energy Storage  

Science Journals Connector (OSTI)

Abstract Solar district heating (SDH) with seasonal thermal energy storage (STES) is a technology to provide heat for space heating and domestic hot water preparation with a high fraction of renewable energy. In order to improve the efficiency of such systems heat pumps can be integrated. By preliminary studies it was discovered, that the integration of a heat pump does not always lead to improvements from an overall energy perspective, although the operation of the heat pump increases the efficiency of other components of the system e. g. the STES or the solar collectors. Thus the integration of heat pumps in SDH systems was investigated in detail. Usually, the heat pumps are integrated in such a way, that the STES is used as low temperature heat source. No other heat sources from the ambience are used and only that amount of energy consumed by the heat pump is additionally fed into the system. In the case of an electric driven heat pump, this is highly questionable concerning economic and CO2-emission aspects. Despite that fact the operation of the heat pump influences positively the performance of other components in the system e. g. the STES and makes them more efficient. If the primary energy consumption of the heat pump is lower than the energetic benefits of all other components, the integration makes sense from an energetic point of view. A detailed assessment has been carried out to evaluate the most promising system configurations for the integration of a heat pump. Based on this approach a system concept was developed in which the integration of the heat pump is energetically further improved compared to realised systems. By means of transient system simulations this concept was optimised with regard to the primary energy consumption. A parameter study of this new concept has been performed to identify the most sensitive parameters of the system. The main result and conclusion are that higher solar fractions and also higher primary energy savings can be achieved by SDH systems using heat pumps compared systems without heat pumps.

Roman Marx; Dan Bauer; Harald Drueck

2014-01-01T23:59:59.000Z

6

State of Maine residential heating oil survey 2001-02 season summary [SHOPP  

SciTech Connect (OSTI)

This, as the title implies, is a summary report of the price trends for heating oil, propane and kerosene heating fuels for the heating season.

Elder, Betsy

2002-05-22T23:59:59.000Z

7

PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP  

E-Print Network [OSTI]

PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. C. Richards and W. L. Auxer General Electric Company Space Division King of Prussia, Pa. ABSTRACT A heat activated heat pump (HAHP for space heating since it directly utilizes the engine waste heat in addition to the energy obtained

Oak Ridge National Laboratory

8

Aquifer thermal energy storage costs with a seasonal heat source.  

SciTech Connect (OSTI)

The cost of energy supplied by an aquifer thermal energy storage (ATES) system from a seasonal heat source was investigated. This investigation considers only the storage of energy from a seasonal heat source. Cost estimates are based upon the assumption that all of the energy is stored in the aquifer before delivery to the end user. Costs were estimated for point demand, residential development, and multidistrict city ATES systems using the computer code AQUASTOR which was developed specifically for the economic analysis of ATES systems. In this analysis the cost effect of varying a wide range of technical and economic parameters was examined. Those parameters exhibiting a substantial influence on ATES costs were: cost of purchased thermal energy; cost of capital; source temperature; system size; transmission distance; and aquifer efficiency. ATES-delivered energy costs are compared with the costs of hot water heated by using electric power or fuel-oils. ATES costs are shown as a function of purchased thermal energy. Both the potentially low delivered energy costs available from an ATES system and its strong cost dependence on the cost of purchased thermal energy are shown. Cost components for point demand and multi-district city ATES systems are shown. Capital and thermal energy costs dominate. Capital costs, as a percentage of total costs, increase for the multi-district city due to the addition of a large distribution system. The proportion of total cost attributable to thermal energy would change dramatically if the cost of purchased thermal energy were varied. It is concluded that ATES-delivered energy can be cost competitive with conventional energy sources under a number of economic and technical conditions. This investigation reports the cost of ATES under a wide range of assumptions concerning parameters important to ATES economics. (LCL)

Reilly, R.W.; Brown, D.R.; Huber, H.D.

1981-12-01T23:59:59.000Z

9

State Heating Oil & Propane Program. Final report 1997/98 heating season  

SciTech Connect (OSTI)

The following is a summary report of the New Hampshire Governor`s Office of Energy and Community Services (ECS) participation in the State Heating Oil and Propane Program (SHOPP) for the 1997/98 heating season. SHOPP is a cooperative effort, linking energy offices in East Coast and Midwest states, with the Department of Energy (DOE), Energy Information Administration (EIA) for the purpose of collecting retail price data for heating oil and propane. The program is funded by the participating state with a matching grant from DOE. SHOPP was initiated in response to congressional inquires into supply difficulties and price spikes of heating oil and propane associated with the winter of 1989/90. This is important to New Hampshire because heating oil controls over 55% of the residential heating market statewide. Propane controls 10% of the heating market statewide and is widely used for water heating and cooking in areas of the state where natural gas is not available. Lower installation cost, convenience, lower operating costs compared to electricity, and its perception as a clean heating fuel have all worked to increase the popularity of propane in New Hampshire and should continue to do so in the future. Any disruption in supply of these heating fuels to New Hampshire could cause prices to skyrocket and leave many residents in the cold.

Hunton, G.

1998-06-01T23:59:59.000Z

10

Thermal and economical analysis of a central solar heating system with underground seasonal storage in Turkey  

Science Journals Connector (OSTI)

Thermal performance and economic feasibility of two types of central solar heating system with seasonal storage under four climatically different Turkey locations are investigated. The effects of storage volume and collector area on the thermal performance and cost are studied for three load sizes. The simulation model of the system consisting of flat plate solar collectors, a heat pump, under ground storage tank and heating load based on a finite element analysis and finite element code ANSYS™ is chosen as a convenient tool. In this study, the lowest solar fraction value for Trabzon (41°N) and the highest solar fraction value for Adana (37°N) are obtained. Based on the economic analysis, the payback period of system is found to be about 25–35 years for Turkey.

A. Ucar; M. Inalli

2005-01-01T23:59:59.000Z

11

Preliminary Analysis of a Solar Heat Pump System with Seasonal Storage for Heating and Cooling  

E-Print Network [OSTI]

and cooling were set up, which is responsible for the space heating and cooling and domestic hot water for a residential block. Through hourly simulation, the performance and the economics of such systems were analyzed, for the different tank volumes...

Yu, G.; Chen, P.; Dalenback, J.

2006-01-01T23:59:59.000Z

12

Heating and cooling performance analysis of a ground source heat pump system in Southern Germany  

Science Journals Connector (OSTI)

Abstract This paper examines thermal performance of a ground source heat pump (GSHP) system. The GSHP system was installed in an office building in Nuremberg city of Germany. In order to evaluate system performance the GSHP system has been continuously monitored for 4 years. Heating and cooling performance of the GSHP system is analyzed based on the accumulated data. Major findings of this work include: (1) coefficient of performance (COP) is estimated to be 3.9 for a typical winter day and energy efficiency ratio (EER) is assessed to be 8.0 for a typical summer day. These results indicate that the GSHP system has a higher efficiency for building cooling than building heating. (2) For a long-term period, the seasonal energy efficiency ratio (SEER) of the GSHP system is observed to increase by 8.7% annually, whereas the seasonal COP is decreased by 4.0% over a 4-year period. The heating and cooling performance of the GSHP system migrates in opposite trend is caused by the unevenly distributed heating and cooling load of the building. This phenomenon deserves serious attention in the design of future GSHP systems in order to avoid the reducing of energy efficiency over long-term operation.

Jin Luo; Joachim Rohn; Manfred Bayer; Anna Priess; Lucas Wilkmann; Wei Xiang

2015-01-01T23:59:59.000Z

13

Thermal and economical analysis of an underground seasonal storage heating system in Thrace  

Science Journals Connector (OSTI)

Economical analysis of the solar heating system with seasonal storage, which was established in Edirne (41°39?54?N) in order to provide the heat requirement of buildings, has been fulfilled. Optimum collector area for the heating system has been determined. Total heat requirement of 69% has been met by means of heating system concerning the space heating and domestic water heating. In the accordance with the results of the economical analysis, the payback time of the heating system has been determined as 19–20 years.

Berrin Karacavus; Ahmet Can

2009-01-01T23:59:59.000Z

14

Study of Applications of Solar Heating Systems with Seasonal Storage in China  

E-Print Network [OSTI]

In most northern parts of China, it is cold in winter and needs space heating in winter. This paper studies applications of solar heating systems with seasonal storage in China. A typical residential district was selected, and a solar heating system...

Yu, G.; Zhao, X.; Chen, P.

2006-01-01T23:59:59.000Z

15

A Seasonal Storage Solar Heating System for the Charlestown, Boston Navy Yard National Historic Park  

Science Journals Connector (OSTI)

This paper concerns the design and analysis of a solar energy system using seasonal heat storage for ... Park in the Charlestown Navy Yard, Boston, Massachusetts. The system uses two existing underground concrete...

D. S. Breger; A. I. Michaels

1984-01-01T23:59:59.000Z

16

State heating oil and propane program: 1995-96 heating season. Final report  

SciTech Connect (OSTI)

This is a summary report of the New Hampshire Governor`s Office of Energy and Community Services (ECS) participation in the State Heating Oil and Propane Program (SHOPP) for the 1995/96 heating season. SHOPP is a cooperative effort, linking energy offices in East Coast and Midwest states, with the Department of Energy (DOE), Energy Information Administration (EIA) for the purpose of collecting retail price data for heating oil and propane. The program funded by the participating state with a matching grant from DOE. EIA provides ECS with a list of oil and propane retailers that serve customers in New Hampshire. In turn ECS conduct phone surveys twice per month from October through March to determine the average retail price for each fuel. Data collected by ECS is entered into the Petroleum Electronic Data Reporting Option (PEDRO) and transmitted via modem to EIA. The results of the state retail price surveys along with wholesale prices, supply, production and stock levels for oil, and propane are published by EIA in the Weekly Petroleum Status Report. Data is also published electronically via the internet or through the Electronic Publication System.

NONE

1996-12-31T23:59:59.000Z

17

Seasonality of the Urban Heat Island Effect in Madison, Wisconsin  

Science Journals Connector (OSTI)

Spatial and temporal variation in the urban heat island (UHI) effect from March 2012 through October 2013 was characterized using continuous temperature measurements from an array of up to 151 fixed sensors in and around Madison, Wisconsin, an ...

Jason Schatz; Christopher J. Kucharik

2014-10-01T23:59:59.000Z

18

Get Ahead of the Heating Season with an Energy Assessment | Department of  

Broader source: Energy.gov (indexed) [DOE]

Ahead of the Heating Season with an Energy Assessment Ahead of the Heating Season with an Energy Assessment Get Ahead of the Heating Season with an Energy Assessment September 7, 2010 - 4:48pm Addthis Andrea Spikes Communicator at DOE's National Renewable Energy Laboratory As I walked outside this morning, I noticed something- a chill in the air! I live in Colorado, where the nights get cooler long before the days do. This is the time where it's common to see people walking around with shorts and sweaters in the morning (gotta be prepared). The sight of my breath was a reminder that soon I'll be running my heater again and will want to run it as little as possible while staying comfortable. If that sounds like your plan, consider scheduling a home energy assessment. Also known as an energy audit, an energy assessment

19

Demonstration and Performance Monitoring of Foundation Heat Exchangers...  

Energy Savers [EERE]

for New and Existing Homes: Foundation Heat Exchanger, Oak Ridge, Tennessee Performance Analysis of Air-Source Variable Speed Heat Pumps and Various Electric Water Heating Options...

20

Enhancing geothermal heat pump systems with parametric performance analyses.  

E-Print Network [OSTI]

??Parametric performance analyses and comparison of a basic geothermal heat pump, a heat pump cycle with motor cooling/refrigerant preheating, and a heat pump cycle utilizing… (more)

Self, Stuart

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Effect of nanofluids on thermal performance of heat pipes.  

E-Print Network [OSTI]

?? A relatively new way for utilizing the thermal performance of heat pipes is to use nanofluids as working fluids in the heat pipes. Heat… (more)

Ferizaj, Drilon

2014-01-01T23:59:59.000Z

22

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...

Huang, Y.; Sun, D.

2006-01-01T23:59:59.000Z

23

Improving Process Heating System Performance: A Sourcebook for...  

Broader source: Energy.gov (indexed) [DOE]

Process Heating System Performance: A Sourcebook for Industry, Second Edition Improving Process Heating System Performance: A Sourcebook for Industry, Second Edition This...

24

DEVELOPMENT OF A HIGH PERFORMANCE COLD CLIMATE HEAT PUMP  

SciTech Connect (OSTI)

The primary goals of the proposed project were to develop, test, and evaluate a high performance and cost-effective vapor compression air-source heat pump for use in cold climate regions. Vapor compression heat pumps are a proven technology, and have been used for many years to meet heating requirements for buildings in residential, commercial, and industrial applications. However, in climate regions that experience very low outdoor ambient temperatures both the heating capacity and coefficient of performance (COP) of traditional air-source vapor compression heat pumps drops dramatically with a decrease in the outdoor air temperature. The efficiency of heat pumping equipment has improved substantially over the past 20 years; however, the efficiencies of the highest rated equipment on the market are approaching practical limits that cannot be surpassed without modifications to the basic cycle and possibly the use of additional hardware. In this report, three technologies to improve the efficiency of vapor compression systems are described. These are a) vapor injected compression, b) oil flooded compression and c) hybrid flow control of the evaporator. Compressor prototypes for both, oil flooded and vapor injected compression were developed by Emerson Climate Technologies. For the oil flooded compressor, the oil injection port location was optimized and an internal oil separator was added using several design iterations. After initial testing at Emerson Climate Technologies, further testing was done at Purdue University, and compressor models were developed. These models were then integrated into a system model to determine the achievable improvement of seasonal energy efficiency (SEER) for Minneapolis (Minnesota) climate. For the oil flooded compression, a 34% improvement in seasonal energy efficiency was found while a 21% improvement in seasonal energy efficiency ratio was found for the vapor injected compression. It was found that one benefit of both tested compression technologies is a lower discharge temperature, which allows for continued operation at lower ambient temperatures. A bin analysis of the vapor injected prototype cold climate heat pump predicts a 6% improvement in HSPF for Minneapolis. This improvement is mainly a result of the increased capacity of the system for active vapor injection. For the oil flooded system, a slightly larger performance improvement is predicted, in this case mostly caused by an increase in heating COP. Based on an economic analysis of these results, the maximum additional cost of the system changes, for the Minneapolis location, are $430 for the vapor injected system and $391 for the oil flooded system. These estimates assume that a 3-year simple payback period is accepted by the customer. For the hybrid flow control of evaporators, a new type of balancing valve was developed together with Emerson Climate technologies to reduce the cost of the control scheme. In contrast to conventional stepper motor valves, this valve requires less cables and can be driven by a cheaper output circuit on the control board. The correct valve size was determined in a dedicated test stand in several design iterations. The performance benefits of the hybrid control of the evaporator coil were determined for clean coil conditions as well as with partial blockage of the air inlet grille and under frosting conditions. For clean coil conditions, the benefits in terms of COP and capacity are negligible. However, significant benefits were noted for severely air-maldistributed operating conditions. For the H2-test, the maximum COP improvement of 17% along with a capacity improvement of nearly 40% was observed. Overall, the hybrid control scheme leads to a significant amount of performance improvement, if the air inlet conditions to the evaporator are maldistributed.

Horton, W. Travis [Purdue University] [Purdue University; Groll, Eckhard A. [Purdue University] [Purdue University; Braun, James E. [Purdue University] [Purdue University

2014-06-01T23:59:59.000Z

25

State of Maine residential heating oil survey: 1995--1996 season summary  

SciTech Connect (OSTI)

In Maine the cash price is surveyed, as opposed to lthe retail or charge price, as it has been identified as the price most often paid by Maine consumers. As one can see from the chart in this report, the 1995-1996 cash prices for No. 2 heating oil can be characterized as having an upward trend and much more fluctuation than last years` relatively flat line. The 1995-96 heating season started at the closing price of the previous season and for the first few weeks prices were lower than most of the 1994-95 trendline. When the weather became cooler, however, prices were on a steady incline until well into the winter. Prices leveled off for most of the rest of the season with a dramatic surge on the last week of the survey. The average statewide cash price for No. 2 heating oil this year was .861 1 cents, approximately ten cents higher than the average for 1994-1995 which was .7661 cents per gallon. It has been the observation of the SPO that during most of the 1995-1996 season, Maine`s prices showed a direct correspondence with New England rack or wholesale prices. It appeared that they never fluctuated more than 3-4 cents from each other.

Elder, B.

1996-05-01T23:59:59.000Z

26

Performance investigation of two geothermal district heating systems for building applications: Energy analysis  

Science Journals Connector (OSTI)

The energetic performance of Balcova geothermal district heating system (BGDHS) and Salihli geothermal district heating system (SGDHS) installed in Turkey is investigated for building applications in this study. The essential components (e.g., pumps, heat exchangers) of these geothermal district heating systems are also included in the modeling. The present model is employed for system analysis and energetic performance evaluation of the geothermal district heating systems. Energy flow diagrams are drawn to exhibit the input and output energies and losses to the surroundings by using the 2003 and 2004 heating season actual data. In addition, energy efficiencies are studied for comparison purposes, and are found to be 39.36% for BGDHS and 59.31% for SGDHS, respectively.

Leyla Ozgener; Arif Hepbasli; Ibrahim Dincer

2006-01-01T23:59:59.000Z

27

Heat Pump Water Heater Performance in  

Broader source: Energy.gov (indexed) [DOE]

searc searc e er tra A Research Institute of the University of Central Florida FLORIDA SOLAR ENERGY CENTER - A Re h Institut of the Univ sity of Cen l Florida searc e er tra Heat Pump Water Heater Performance in Laboratory House Building America Technical Update 2013 ACI National Home Performance Conference April 29- 30 , 2013 Carlos J. Colon carlos@fsec.ucf.edu A Research Institute of the University of Central Florida FLORIDA SOLAR ENERGY CENTER - A Re h Institut of the Univ sity of Cen l Florida FLORIDA SOLAR ENERGY CENTER - A Research Institute of the University of Central Florida Hot Water Systems (HWS) Laboratory FSEC Grounds, Florida (east coast) 2009 -Present (Currently fourth testing rotation) FLORIDA SOLAR ENERGY CENTER - A Research Institute of the University of Central Florida

28

SYSTEM PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP  

E-Print Network [OSTI]

AUG 1979 SYSTEM PERFORMANCE OF A STIRLING ENGINE POWERED HEAT ACTIVATED HEAT PUMP W. D. Richards W The development of the first prototype heat activated heat pump (HAHP) jointly sponsored by the Gas Research as a unitary heating and cooling product competing for the same market as is currently served by the gas year

Oak Ridge National Laboratory

29

XI. DIFFUSEGLOBAL CORRELATIONS: SEASONAL VARIATIONS Estimating the performance of a solar system  

E-Print Network [OSTI]

is measured on a horizontal surface and intensity on the tilted collector surface is calculated via a two39 XI. DIFFUSE­GLOBAL CORRELATIONS: SEASONAL VARIATIONS Estimating the performance of a solar system requires an accurate assessment of incident solar radiation. Ordinarily, solar radiation

Oregon, University of

30

Experimental performance of solid-gas chemical heat pump in solar chemical heat pump dryer  

Science Journals Connector (OSTI)

A solar assisted chemical heat pump dryer has been designed, fabricated and tested. The performance of the system has been studied under the meteorological conditions of Malaysia. The system consists of four mean components: solar collector (evacuated ... Keywords: coefficient of performance, drying, energy density, evacuated tubes solar collector, reactor temperature, solid gas chemical heat pump

M. Ibrahim; K. Sopian; A. S. Hussein; W. R. W. Daud; A. Zaharim

2009-02-01T23:59:59.000Z

31

Solar energy system performance evaluation. Seasonal report for Fern Lansing, Lansing, Michigan  

SciTech Connect (OSTI)

The Solar Energy System was designed by Fern Engineering Company, Bourne, Massachusetts to provide space heating and domestic hot water preheating for a 1300 square foot single-family residence located in Lansing, Michigan. The Solar Energy System consists of a 278 square foot flat-plate air collector subsystem, a three 120-gallon tank storage subsystem, a 40 gallon domestic hot water tank subsystem, a liquid/air heat exchanger, an energy transport module, pumps, controls and heat transfer medium lines. Natural gas provides the auxiliary energy for the space heating (100,000 Btu/h) and hot water (70,000 Btu/h) subsystems. The system is shown schematically and has five modes of operation. Typical system operation, system operating sequence, performance assessment, system performance, subsystems performance (collector array, storage, hot water, space heating), operating energy, energy savings, and maintenance are discussed. A brief summary of all pertinent parameters is presented.

Not Available

1980-06-01T23:59:59.000Z

32

Water-to-Air Heat Pump Performance with Lakewater  

E-Print Network [OSTI]

The performance of water-to-air heat pumps using lakewater as the heat source and sink has been investigated. Direct cooling with deep lakewater has also been considered. Although the emphasis of the work was with southern lakes, many results also...

Kavanaugh, S.; Pezent, M. C.

1989-01-01T23:59:59.000Z

33

The effects of outdoor heat exchanger hydrophobic treatment on the performance of an air source heat pump.  

E-Print Network [OSTI]

??The effects of outdoor heat exchanger hydrophobic treatment on the performance of an air source heat pump were investigated. The base case tests used a… (more)

Parker, Brandon DeWayne

2012-01-01T23:59:59.000Z

34

Performance Analysis of Air-Source Variable Speed Heat Pumps and Various Electric Water Heating Options  

Broader source: Energy.gov (indexed) [DOE]

Analysis of Air- Analysis of Air- Source Variable Speed Heat Pumps and Various Electric Water Heating Options Jeffrey Munk Oak Ridge National Laboratory 2 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Acknowledgements * Tennessee Valley Authority - David Dinse * U.S. Department of Energy * Roderick Jackson * Tony Gehl * Philip Boudreaux * ZEBRAlliance 3 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Overview * Electric Water Heating Options - Conventional Electric Water Heaters - Heat Pump Water Heaters * Air-Source * Ground-Source - Solar Thermal Water Heater * Variable Speed Heat Pumps - Energy Use Analysis - Measured Performance - Operational Characteristics 4 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Water Heating Options

35

The performance of ICRF heated plasmas in LHD  

Science Journals Connector (OSTI)

An ion cyclotron range of frequency (ICRF) heating experiment was conducted in the third campaign of LHD in 1999. 1.35 MW of ICRF power were injected into the plasma and 200 kJ of stored energy were obtained, which was maintained for 5 s by ICRF power only after the termination of ECH. The impurity problem was so completely overcome that the pulse length was easily extended to 68 s at a power level of 0.7 MW. The utility of a liquid stub tuner in steady state plasma heating was demonstrated in this discharge. The energy confinement time of the ICRF heated plasma has the same dependences on plasma parameters as those of the ISS95 stellarator scaling with a multiplication factor of 1.5, which is a high efficiency comparable to that of NBI. Such an improvement in performance was obtained by various means, including: (a) scanning of the magnetic field intensity and minority concentration, (b) improvement of particle orbits due to a shift of magnetic axis and (c) reduction of the number of impurity ions by means of titanium gettering and the use of carbon divertor plates. In the optimized heating regime, ion heating turned out to be the dominant heating mechanism, unlike in CHS and W7-AS. Owing to the high quality of the heating and the parameter range being extended far beyond that of previous experiments, the experiment can be regarded as the first complete demonstration of ICRF heating in stellarators.

T. Watari; T. Mutoh; R. Kumazawa; T. Seki; K. Saito; Y. Torii; Yan Ping Zhao; D. Hartmann; H. Idei; S. Kubo; K. Ohkubo; M. Sato; T. Shimozuma; Y. Yoshimura; K. Ikeda; O. Kaneko; Y. Oka; M. Osakabe; Y. Takeiri; K. Tsumori; N. Ashikawa; P.C. De Vries; M. Emoto; A. Fukuyama; H. Funaba; M. Goto; K. Ida; S. Inagaki; N. Inoue; M. Isobe; K. Itoh; S. Kado; K. Kawahata; K. Khlopenkov; T. Kobuchi; A. Komori; A.V. Krasilnikov; Y. Liang; S. Masuzaki; K. Matsuoka; T. Minami; J. Miyazawa; T. Morisaki; S. Morita; S. Murakami; S. Muto; Y. Nagayama; Y. Nakamura; H. Nakanishi; K. Narihara; K. Nishimura; N. Noda; A.T. Notake; S. Ohdachi; N. Ohyabu; H. Okada; M. Okamoto; T. Ozaki; R.O. Pavlichenko; B.J. Peterson; A. Sagara; S. Sakakibara; R. Sakamoto; H. Sasao; M. Sasao; K. Sato; S. Satoh; T. Satow; M. Shoji; S. Sudo; H. Suzuki; M. Takechi; N. Tamura; S. Tanahashi; K. Tanaka; K. Toi; T. Tokuzawa; K.Y. Watanabe; T. Watanabe; H. Yamada; I. Yamada; S. Yamaguchi; S. Yamamoto; K. Yamazaki; M. Yokoyama; Y. Hamada; O. Motojima; M. Fujiwara

2001-01-01T23:59:59.000Z

36

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters  

SciTech Connect (OSTI)

This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt(tm) whole-house building simulations.

Sparn, B.; Hudon, K.; Christensen, D.

2014-06-01T23:59:59.000Z

37

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Performance Performance Evaluation of Residential Integrated Heat Pump Water Heaters B. Sparn, K. Hudon, and D. Christensen Technical Report NREL/TP-5500-52635 September 2011 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 1617 Cole Boulevard Golden, Colorado 80401 303-275-3000 * www.nrel.gov Contract No. DE-AC36-08GO28308 Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters B. Sparn, K. Hudon, and D. Christensen Prepared under Task Nos. WTN9.1000, ARRB.2204 Technical Report NREL/TP-5500-52635 September 2011 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government.

38

Performance of Horizontal Field Earth-Coupled Heat Pumps  

E-Print Network [OSTI]

An alternative to traditional methods of residential heating and cooling is the heat pump. However, heat pumps which use the outside air as a heat source/sink become inefficient during the periods of highest demand. Another possible heat source...

Abbott, C. A.

1986-01-01T23:59:59.000Z

39

Michigan residential No. 2 fuel oil and propane price survey for the 1990/91 heating season. Final report  

SciTech Connect (OSTI)

This report summarizes the results of a survey of home heating oil and propane prices over the 1990/1991 heating season in Michigan. The survey was conducted under a cooperative agreement between the State of Michigan, Michigan Public Service Commission and the US Department of Energy (DOE), Energy Information Administration (EIA), and was funded by a grant from EIA. From October 1990 through May 1991, participating dealers/distributions were called and asked for their current residential retail prices of No. 2 home heating oil and propane. This information was then transmitted to the EIA, bi-monthly using an electronic reporting system called Petroleum Data Reporting Option (PEDRO). The survey was conducted using a sample provided by EIA of home heating oil and propane retailers which supply Michigan households. These retailers were contacted the first and third Mondays of each month. The sample was designed to account for distributors with different sales volumes, geographic distributions and sources of primary supply. It should be noted that this simple is different from the sample used in prior year surveys.

Not Available

1991-10-01T23:59:59.000Z

40

Michigan residential No. 2 fuel oil and propane price survey for the 1990/91 heating season  

SciTech Connect (OSTI)

This report summarizes the results of a survey of home heating oil and propane prices over the 1990/1991 heating season in Michigan. The survey was conducted under a cooperative agreement between the State of Michigan, Michigan Public Service Commission and the US Department of Energy (DOE), Energy Information Administration (EIA), and was funded by a grant from EIA. From October 1990 through May 1991, participating dealers/distributions were called and asked for their current residential retail prices of No. 2 home heating oil and propane. This information was then transmitted to the EIA, bi-monthly using an electronic reporting system called Petroleum Data Reporting Option (PEDRO). The survey was conducted using a sample provided by EIA of home heating oil and propane retailers which supply Michigan households. These retailers were contacted the first and third Mondays of each month. The sample was designed to account for distributors with different sales volumes, geographic distributions and sources of primary supply. It should be noted that this simple is different from the sample used in prior year surveys.

Not Available

1991-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

The effects of outdoor heat exchanger hydrophobic treatment on the performance of an air source heat pump  

E-Print Network [OSTI]

THE EFFECTS OF OUTDOOR HEAT EXCHANGER HYDROPHOBIC TREATMENT ON THE PERFORMANCE OF AN AIR SOURCE HEAT PUMP A Thesis by BRANDON DEWAYNE PARKER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1995 Major Subject: Mechanical Engineering THE EFFECTS OF OUTDOOR HEAT EXCHANGER HYDROPHOBIC TREATMENT ON THE PERFORMANCE OF AN AIR SOURCE HEAT PUMP A Thesis by BRANDON DEWAYNE PARKER Submitted...

Parker, Brandon DeWayne

2012-06-07T23:59:59.000Z

42

Demonstration and Performance Monitoring of Foundation Heat Exchangers in Low Load, High Performance Research Homes  

Broader source: Energy.gov (indexed) [DOE]

Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Low Load, High Performance Research Homes Piljae Im, Ph.D. Oak Ridge National Laboratory Building America Technical Update Meeting April 29 - 30, Denver, Colorado ACKNOWLEDGEMENT * This project was sponsored by the Building Technologies Office of the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy and the Tennessee Valley Authority (TVA). Managed by UT-Battelle for the U.S. Department of Energy 2 PRESENTATION OVERVIEW * INTRODUCTION * FIELD TEST OF THE FOUNDATION HEAT EXCHANGER (FHX) CONCEPT * FOUNDATION HEAT EXCHANGER PERFORMANCE MEASUREMENTS * ADDITIONAL FINDINGS AND COST COMPARISON * SUMMARY Managed by UT-Battelle for the U.S. Department of Energy

43

Performance analysis of wick-assisted heat pipe solar collector and comparison with experimental results  

Science Journals Connector (OSTI)

The performance of heat pipe solar collector is investigated theoretically and experimentally. The system employs wick-assisted heat pipe for the heat transfer from ... pipe temperature and also the thermal effic...

E. Azad

2009-03-01T23:59:59.000Z

44

Seasonal thermal signatures of heat transfer by water exchange in an underground vault  

Science Journals Connector (OSTI)

......such a cavity, water phases do not need...place, and vertical water flow can be small...Aburatsubo, with a recovery time larger than...heat transfer by water exchange. This...evaporation and condensation process. If the...Monitoring the atmospheric temperature in a......

Frédéric Perrier; Pierre Morat; Toshio Yoshino; Osam Sano; Hisashi Utada; Olivier Gensane; Jean-Louis Le Mouël

2004-07-01T23:59:59.000Z

45

Performance of Variable Capacity Heat Pumps in a Mixed Humid Climate  

SciTech Connect (OSTI)

Variable capacity heat pumps represent the next wave of technology for heat pumps. In this report, the performance of two variable capacity heat pumps (HPs) is compared to that of a single or two stage baseline system. The units were installed in two existing research houses located in Knoxville, TN. These houses were instrumented to collect energy use and temperature data while both the baseline systems and variable capacity systems were installed. The homes had computer controlled simulated occupancy, which provided consistent schedules for hot water use and lighting. The temperature control and energy use of the systems were compared during both the heating and cooling seasons. Multiple linear regression models were used along with TMY3 data for Knoxville, TN in order to normalize the effect that the outdoor air temperature has on energy use. This enables a prediction of each system's energy use over a year with the same weather. The first system was a multi-split system consisting of 8 indoor units and a single outdoor unit. This system replaced a 16 SEER single stage HP with a zoning system, which served as the baseline. Data was collected on the baseline system from August 2009 to December 2010 and on the multi-split system from January 2011 to January 2012. Soon after the installation of the multi-split system, some of the smaller rooms began over-conditioning. This was determined to be caused by a small amount of continuous refrigerant flow to all of the indoor units when the outdoor unit was running regardless of whether they were calling for heat. This, coupled with the fact that the indoor fans run continuously, was providing enough heat in some rooms to exceed the set point. In order to address this, the indoor fans were disabled when not actively heating per the manufacturer's recommendation. Based on the measured data, the multi-split system was predicted to use 40% more energy in the heating season and 16% more energy in the cooling season than the baseline system, for the typical meteorological year weather data. The AHRI ratings indicated that the baseline system would perform slightly better than the multi-split system, but not by as large of a margin as seen in this study. The multi-split system was able to maintain more consistent temperature throughout the house than the baseline system, but it did allow relative humidity levels to increase above 60% in the summer. The second system was a split system with an inverter driven compressor and a single ducted air handler. This unit replaced a 16 SEER two stage HP with a zoning system. Data was collected on the baseline system from July 2009 to November 2010 and on the ducted inverter system from December 2010 to January 2012. The ducted inverter system did not offer a zone controller, so it functioned as a single zone system. Due to this fact, the registers had to be manually adjusted in order to better maintain consistent temperatures between the two levels of the house. The predicted heating season energy use for the ducted inverter system, based on the measured energy use, was 30% less than that of the baseline system for the typical meteorological year. However, the baseline system was unable to operate in its high stage due to a wiring issue with the zone controller. This resulted in additional resistance heat use during the winter and therefore higher energy use than would be expected in a properly performing unit. The AHRI ratings would indicate that the baseline system would use less energy than the ducted inverter system, which is opposite to the results of this study. During the cooling season, the ducted inverter system was predicted to use 23% more energy than the baseline system during the typical meteorological year. This is also opposite of the results expected by comparing the AHRI ratings. After a detailed comparison of the ducted inverter system's power use compared to that of a recently installed identical system at a retro-fit study house, there is concern that the unit is not operating as intended. The power use and cycles indicate t

Munk, Jeffrey D [ORNL; Gehl, Anthony C [ORNL; Jackson, Roderick K [ORNL

2012-04-01T23:59:59.000Z

46

The Coupling Performance of a Solar-Air Heat Pump  

Science Journals Connector (OSTI)

Based on the advantages and disadvantages of single air source heat pump, single solar energy heat pump and switch solar-air dual heat source heat pumps, a new type of solar-air composite heat source heat pump system has been proposed to realize the utilization and complementary advantages of two renewable energy: air and solar. It also provided a feasible method to improve the city's ecological environment, and plays a leading role in the villages and small towns’ construction. Design the composite heat exchanger with double heat sources. The heat exchanger had dual function of tube-fin and tube heat exchangers, break through the traditional model that heat exchanger in working can realize heat exchange only between the same gases or liquid heat sources, and realized the heat exchange between two heat sources. It laid the technological and equips mental foundation for realizing the synchronization and composite using of solar energy and air.

Yin Liu; Jing Ma; Guanghui Zhou

2011-01-01T23:59:59.000Z

47

Seasonal versus Episodic Performance Evaluation for an Eulerian Photochemical Air Quality Model  

SciTech Connect (OSTI)

This study presents detailed evaluation of the seasonal and episodic performance of the Community Multiscale Air Quality (CMAQ) modeling system applied to simulate air quality at a fine grid spacing (4 km horizontal resolution) in central California, where ozone air pollution problems are severe. A rich aerometric database collected during the summer 2000 Central California Ozone Study (CCOS) is used to prepare model inputs and to evaluate meteorological simulations and chemical outputs. We examine both temporal and spatial behaviors of ozone predictions. We highlight synoptically driven high-ozone events (exemplified by the four intensive operating periods (IOPs)) for evaluating both meteorological inputs and chemical outputs (ozone and its precursors) and compare them to the summer average. For most of the summer days, cross-domain normalized gross errors are less than 25% for modeled hourly ozone, and normalized biases are between {+-}15% for both hourly and peak (1 h and 8 h) ozone. The domain-wide aggregated metrics indicate similar performance between the IOPs and the whole summer with respect to predicted ozone and its precursors. Episode-to-episode differences in ozone predictions are more pronounced at a subregional level. The model performs consistently better in the San Joaquin Valley than other air basins, and episodic ozone predictions there are similar to the summer average. Poorer model performance (normalized peak ozone biases <-15% or >15%) is found in the Sacramento Valley and the Bay Area and is most noticeable in episodes that are subject to the largest uncertainties in meteorological fields (wind directions in the Sacramento Valley and timing and strength of onshore flow in the Bay Area) within the boundary layer.

Jin, Ling; Brown, Nancy J.; Harley, Robert A.; Bao, Jian-Wen; Michelson, Sara A; Wilczak, James M

2010-04-16T23:59:59.000Z

48

THERMAL PERFORMANCE MEASUREMENTS ON ULTIMATE HEAT SINKS - COOLING PONDS  

Office of Scientific and Technical Information (OSTI)

THERMAL PERFORMANCE MEASUREMENTS THERMAL PERFORMANCE MEASUREMENTS ON ULTIMATE HEAT SINKS - COOLING PONDS R. K. Hadlock 0 . B. Abbey Battelle Pacific Northwest Laboratories Prepared for U. S. Nuclear Regulatory Commission b + NOTICE This report was prepared as an account of work sponsored by the United States Government. Neither the United States nor the United States Nuclear Regulatory Commission, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, nor assumes any legal liability or responsibility for the accuracy, completeness or usefulness of any information, apparatus, pro- duct or process disclosed, nor represents that its use would not infringe privately owned rights. F Available from National Technical Information Service

49

Parametric Investigation of the Performance of Solar Heating Systems with Rock Bed Storage  

Science Journals Connector (OSTI)

The performance of solar air collector domestic heating systems with rock bed storage, as obtained from theoretical analysis, is...

W. L. Dutre; J. Vanheelen

1981-01-01T23:59:59.000Z

50

High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns  

E-Print Network [OSTI]

AND LIQUID now PATHS fOA IltO TltAYS I A number of engineering contractors and 1 operating companies have employed Union Carbide'\\s High Flux and Multiple Downcomer tray technolog~es to improve performance, decrease utilities and I lower operating costs... ? Fi,?'d as nll\\ximum within hf'l~ht n'!:-;tl'ie-tlon. The control scheme for a heat pump can be de signed to be no more complex than a conventional steam/cooling water system which relies on flow and level controllers to set the various column flow...

Wisz, M. W.; Antonelli, R.; Ragi, E. G.

1981-01-01T23:59:59.000Z

51

The impact of TXV heating on the performance of air-source heat pump in heating mode  

SciTech Connect (OSTI)

The paper discusses the strategy of TXV heating, which adds a limited amount of heat on the surface of TXV sensor, to achieve energy saving and low cost in air-source heat pumps. The TXV heating is able to retard the valve closing so as to boost energy saving in heating mode. The testing results demonstrate the appropriate TXV heating achieves a remarkable improvement in COP and thermal comfort. The required heating power is not more than 40w. The additional equipment cost of TXV heating is less than $20. Thus, the strategy of TXV heating is practical from the view of technology and economy.

Gao, Zhiming [ORNL

2010-01-01T23:59:59.000Z

52

On the performance of the flat plate solar heat collector  

Science Journals Connector (OSTI)

A flat plate heat collector was constructed for the purpose of heating water by solar energy. It was erected facing south, tilted to the horizontal at the optimum tilt angle, and tested ... was found, for the dim...

M. K. Elnesr; A. M. Khalil

1965-01-01T23:59:59.000Z

53

High-Performance Commercial Cold Climate Heat Pump | Department...  

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

cold climate commercial heat pump system. The system improves on state-of-the-art heat pumps, which can degrade by up to 60% in capacity and 50% in system coefficient of...

54

Performance of solid-gas chemical heat pump subsystem of solar dryer  

Science Journals Connector (OSTI)

In this paper the performance of solid-gas chemical heat pump subsystem of solar dryer has been investigated. A thermodynamic analysis is presented to upgrade solar energy with solid-gas chemical heat pump for agriculture drying purpose. A solar assisted ... Keywords: coefficient of performance (COPh), drying, evacuated tubes, overall COPs, solar, solid gas chemical heats pump

M. Ibrahim; W. R. W. Daud; Kamaruzaman Ibrahim; Azami Zaharim; Kamaruzaman Sopian

2010-01-01T23:59:59.000Z

55

NREL Evaluates Performance of Heat Pump Water Heaters (Fact Sheet)  

SciTech Connect (OSTI)

NREL evaluates energy savings potential of heat pump water heaters in homes throughout all U.S. climate zones.

Not Available

2012-02-01T23:59:59.000Z

56

Management and Control for Optimal Performance of the Heating Substation  

E-Print Network [OSTI]

With the development of the scale of central heating, a higher managing level is needed for the heating substation. How to economize the more energy is the first factor that managers need to consider while ensuring the comfort of the heating...

Yang, J.

2006-01-01T23:59:59.000Z

57

Performance analysis of a solar-assisted heat pump with an evacuated tubular collector for domestic heating  

Science Journals Connector (OSTI)

Performance of a solar-assisted heat pump with an evacuated tubular collector has been analyzed both theoretically and experimentally. A domestic heating system has been designed, constructed and tested. The evacuated tubular solar collector has been used to achieve higher collector efficiencies. The effects of evaporation temperature on the heating capacity and performance of the system have been investigated. Evaporation temperature varies between 5.2 and 20.7 °C while storage tank temperature varies between 9 and 35 °C. The maximum value of the coefficient of performance of the solar assisted heat pump is obtained as 6.38 experimentally. The calculated and experimental results are seen to be in a good agreement. A cost analysis of the proposed system is made comparing with a non-solar heat pump system.

Ahmet Ça?lar; Cemil Yamal?

2012-01-01T23:59:59.000Z

58

Solar-powered/fuel-assisted Rankine-cycle power and cooling system: Simulation method and seasonal performance  

SciTech Connect (OSTI)

The subject of this analysis is a solar cooling system based on a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100/sup 0/C, and it is then superheated to about 600/sup 0/C in a fossil-fuel-fired superheater. The addition of about 20-26 percent of fuel doubles the power cycle's efficiencyas compared to organic Rankine cycles operating at similar collector temperatures. A comprehensive computer program was developed to analyze the operation and performance of the entire power/cooling system. Transient simulation was performed on an hourly basis over a cooling season in two representative climatic regions (Washington, D.C. and Phoenix, Ariz.). One of the conclusions is that the seasonal system COP is 0.82 for the design configuration and that the use of watercooled condensers and flat-plate collectors of higher efficiency increases this value to 1.35.

Lior, N.; Koai, K.

1984-05-01T23:59:59.000Z

59

Ground and Water Source Heat Pump Performance and Design for Southern Climates  

E-Print Network [OSTI]

Ground and water source heat pump systems have very attractive performance characteristics when properly designed and installed. These systems typically consist of a water-to-air or water-to-water heat pump linked to a closed loop vertical...

Kavanaugh, S.

1988-01-01T23:59:59.000Z

60

Large Solar Assisted Heat Pump Systems in Collective Housing: In-situ Monitoring Results for Summer Season  

Science Journals Connector (OSTI)

Abstract This article presents the behavior of an existing system combining solar collectors and heat pumps at large scale (10’000 living m2, more than 1’000 m2 solar collectors) for space heating and domestic hot water production, focusing on summer period. Ongoing detailed monitoring enables to measure its energy performance. The monitoring results for 2012 show a system SPF of 2.9 (2.6 in winter and 4.4 in summer). The direct solar fraction in summer is lower than 50%, which is low considering the oversizing of the solar collector area for domestic hot water production. The high domestic hot water demand (?50 kWh/m2/yr whereas the usual value is around 20) can partly explain this low value, but other factors should also be considered. The results presented in this article are part of a research project aiming to assess the relevance of the concept of coupling solar thermal and heat pumps in various types of building (especially existing buildings with low efficient thermal envelope).

Carolina Fraga; Floriane Mermoud; Pierre Hollmuller; Eric Pampaloni; Bernard Lachal

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Exergy Optimized Wastewater Heat Recovery: Minimizing Losses and Maximizing Performance  

E-Print Network [OSTI]

the heat using a batch process with an insulated tank containing a heat exchanger. The analysis is based on statistical annual hot water usage profiles. The system shows that the exergy available in warm wastewater can be optimized with specific tank size...

Meggers, F.

62

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters  

SciTech Connect (OSTI)

This report discusses how a significant opportunity for energy savings is domestic hot water heating, where an emerging technology has recently arrived in the U.S. market: the residential integrated heat pump water heater. A laboratory evaluation is presented of the five integrated HPWHs available in the U.S. today.

Sparn, B.; Hudon, K.; Christensen, D.

2011-09-01T23:59:59.000Z

63

E-Print Network 3.0 - air-to-air heat pumps Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

conditions... data on the seasonal performance of air-to-air residential heat pump systems. The purpose of this paper... of operation 10, 197778, the Control House ......

64

The Influence of Heat Transfer Irreversibilities on the Optimal Performance of Diabatic  

E-Print Network [OSTI]

The Influence of Heat Transfer Irreversibilities on the Optimal Performance of Diabatic is only slightly dependent on the heat transfer law considered. In the limit of an infinite number of trays even this column with resistance to transfer of heat becomes reversible. 1 #12;Keywords Diabatic

Salamon, Peter

65

PERFORMANCE ANALYSIS OF A RESIDENTIAL GROUND SOURCE HEAT PUMP SYSTEM WITH ANTIFREEZE SOLUTION  

E-Print Network [OSTI]

PERFORMANCE ANALYSIS OF A RESIDENTIAL GROUND SOURCE HEAT PUMP SYSTEM WITH ANTIFREEZE SOLUTION M in a ground source heat pump system falls near or below 0o C, an antifreeze mixture must be used to prevent freezing in the heat pump. The antifreeze mixture type and concentration has a number of implications

66

THE EFFECT OF LOCATION OF THE PREDICTED PERFORMANCE OF A HEAT PUMP WATER HEATER  

E-Print Network [OSTI]

#12;THE EFFECT OF LOCATION OF THE PREDICTED PERFORMANCE OF A HEAT PUMP WATER HEATER Laboratory testing and field testing have shown that a heat pump water heater (HPWH) uses about half the electrical energy input that an electric resistance water heater does. However, since the heat pump water heater

Oak Ridge National Laboratory

67

Performance Evaluation of a Retrofit Industrial Heat Pump  

E-Print Network [OSTI]

the choice of power generation and heat pumping should be employed. The simplistic answer to only pump heat across the pinch will not provide sufficient guidance. The purpose of this paper is to provide a simple but accurate analysis to any process... that will indicate where power should be made through cogeneration and even prime power use as well as where heat pumps should be employed. Actual case studies are provided to illustrate the analytical framework and actual results for a small refinery, chemical...

Wagner, J.R.

68

Energy Performance Comparison of Heating and Air Conditioning Systems for Multi-Family Residential Buildings  

SciTech Connect (OSTI)

The type of heating, ventilation and air conditioning (HVAC) system has a large impact on the heating and cooling energy consumption in multifamily residential buildings. This paper compares the energy performance of three HVAC systems: a direct expansion (DX) split system, a split air source heat pump (ASHP) system, and a closed-loop water source heat pump (WSHP) system with a boiler and an evaporative fluid cooler as the central heating and cooling source. All three systems use gas furnace for heating or heating backup. The comparison is made in a number of scenarios including different climate conditions, system operation schemes and applicable building codes. It is found that with the minimum code-compliant equipment efficiency, ASHP performs the best among all scenarios except in extremely code climates. WSHP tends to perform better than the split DX system in cold climates but worse in hot climates.

Wang, Weimin; Zhang, Jian; Jiang, Wei; Liu, Bing

2011-07-31T23:59:59.000Z

69

A key review on performance improvement aspects of geothermal district heating systems and applications  

Science Journals Connector (OSTI)

This paper deals with a comprehensive analysis and discussion of geothermal district heating systems and applications. In this regard, case studies are presented to study the thermodynamic aspects in terms of energy and exergy and performance improvement opportunities of three geothermal district heating systems, namely (i) Balcova geothermal district heating system (BGDHS), (ii) Salihli geothermal district heating system (SGDHS), and (iii) Gonen geothermal district heating system (GGDHS) installed in Turkey. Energy and exergy modeling of geothermal district heating systems for system analysis and performance evaluation are given, while their performances are evaluated using energy and exergy analysis method. Energy and exergy specifications are presented in tables. In the analysis, the actual system operational data are utilized. In comparison of the local three district heating systems with each other, it is found that the SGDHS has highest energy efficiency, while the GGDHS has highest exergy efficiency.

Leyla Ozgener; Arif Hepbasli; Ibrahim Dincer

2007-01-01T23:59:59.000Z

70

Investigation of new heat exchanger design performance for solar thermal chemical heat pump.  

E-Print Network [OSTI]

?? The emergence of Thermally Driven Cooling system has received more attention recently due to its ability to utilize low grade heat from engine, incinerator… (more)

Cordova, Cordova

2013-01-01T23:59:59.000Z

71

Influence of row spacing on performance of short-season cotton genotypes  

E-Print Network [OSTI]

. Hand har- vests were made at 121, 137, and 174 days after planting (DAP) on 1 Mention of commercial products or trade names is for identifica- tion only and does not imply endorsement by the author or Texas A&M University. 15 3-m row sections.../ha. Percentage maturity was determined at 121 ard 137 days after planting. At each date, differences among spacing treatments were non-significant. Genotype differences were significant at both dates; at 121 DAP, the long-season check variety (genotype 10...

Abreu, Jose?

2012-06-07T23:59:59.000Z

72

Biomass heat pipe reformer—design and performance of an indirectly heated steam gasifier  

Science Journals Connector (OSTI)

Indirectly heated dual fluidized bed (DFB) gasifiers are a promising option for the production ... syngas, in particular in the small- and medium-scale range. The application of so-called ... pipes solves the key...

Jürgen Karl

2014-03-01T23:59:59.000Z

73

Experimental performance analysis of a solar assisted ground source heat pump system under different heating operation modes  

Science Journals Connector (OSTI)

Abstract This paper presents an experimental study on the influence of operation modes on the heating performance of a solar assisted ground source heat pump system (SAGSHPS). Through experiments conducted in January, the characteristics of the SAGSHPS were investigated under different heating operation modes. The results indicate that the solar thermal could be used to accelerate the soil recovery when the heat pump unit is turned off, but the duration of solar use to recharge boreholes should be optimized according to the water temperature in the solar heat storage water tank to avoid unnecessary power consumption of the circulation pump. In addition, the solar heat storage water tank is beneficial for the stable operation of the SAGSHPS. The volumetric flow rate in the water tank has a significant impact on the electricity consumption of the SAGSHPS. From comprehensive analysis of the integral effect of the SAGSHPS under different modes, the mode in which the water tank is connected with the ground heat exchangers (GHES) in series is the recommended mode for the SAGSHPS in the coldest month in Dalian.

Lanhua Dai; Sufen Li; Lin DuanMu; Xiangli Li; Yan Shang; Ming Dong

2015-01-01T23:59:59.000Z

74

Building America Expert Meeting: Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems  

Broader source: Energy.gov [DOE]

Water heating represents a major residential energy end use, especially in highly efficient homes where space conditioning loads and energy use has been significantly reduced. Future efforts to reduce water heating energy use requires the development of an improved understanding of equipment performance, as well as recognizing system interactions related to the distribution system and the fixture use characteristics. By bringing together a group of water heating experts, we hope to advance the shared knowledge on key water heating performance issues and identify additional data needs that will further this critical research area.

75

High-Performance Refrigerator Using Novel Rotating Heat Exchanger  

Broader source: Energy.gov [DOE]

Lead Performer: Oak Ridge National Laboratory – Oak Ridge, TNPartners:-- University of Maryland – College Park, MD-- Sandia National Laboratory – Livermore, CA

76

Design and Development of an Intelligent Energy Controller for Home Energy Saving in Heating/Cooling System .  

E-Print Network [OSTI]

??Energy is consumed every day at home as we perform simple tasks, such as watching television, washing dishes and heating/cooling home spaces during season of… (more)

Abaalkhail, Rana

2012-01-01T23:59:59.000Z

77

Performance analysis of reciprocating regenerative magnetic heat pumping. Final report  

SciTech Connect (OSTI)

Transient flow phenomena in the regenerator tube of reciprocating magnetic heat pumps have been studied numerically and experimentally. In the numerical study, two approaches were taken: (1) solving the energy balance equations for fluid through a porous bed directly and (2) solving the Navier-Stokes equations with a buoyancy force term in the momentum equation. A flow thermal mixing problem was found in both approaches because of the piston-like motion of the regenerator tube that hinders the development of the temperature. The numerical study results show that a 45 K temperature span can be reached in 10 minutes of charge time through the use of a 7-Tesla magnetic field. Using the second numerical approach, temperature stratification in the regenerator fluid column was clearly indicated through temperature rasters. The study also calculates regenerator efficiency and energy delivery rates when heating load and cooling load are applied. Piecewise variation of the regenerator tube moving speed has been used in the present numerical study to control the mass flow rate, reduce thermal mixing of the flow and thus the regenerative losses. The gadolinium`s adiabatic temperature has been measured under 6.5 Tesla of magnet field and different of operating temperatures ranging from 285 K to 320 K. Three regenerative heat pumping tests have also been conducted based on the Reynolds number of the regenerator tube flow, namely Re=300, Re=450, and Re=750 without loads. Maximum temperature span are 12 & 11 K and 9 K for the case of Re=300, Re=450 and Re=750, respectively. Experimental data are in good agreement with the numerical calculation results, and have been used to calibrate the numerical results and to develop a design database for reciprocating-type room-temperature magnetic heat pumps.

Chen, D.T. [Oak Ridge Associated Universities, Inc., TN (United States); Murphy, R.W.; Mei, V.C.; Chen, F.C.; Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States)

1994-02-01T23:59:59.000Z

78

Performance of an experimental ground-coupled heat pump system for heating, cooling and domestic hot-water operation  

Science Journals Connector (OSTI)

Abstract The ground-coupled heat pump (GCHP) system is a type of renewable energy technology providing space heating and cooling as well as domestic hot water. However, experimental studies on GCHP systems are still insufficient. This paper first presents an energy-operational optimisation device for a GCHP system involving insertion of a buffer tank between the heat pump unit and fan coil units and consumer supply using quantitative adjustment with a variable speed circulating pump. Then, the experimental measurements are used to test the performance of the GCHP system in different operating modes. The main performance parameters (energy efficiency and CO2 emissions) are obtained for one month of operation using both classical and optimised adjustment of the GCHP system, and a comparative analysis of these performances is performed. In addition, using TRNSYS (Transient Systems Simulation) software, two simulation models of thermal energy consumption in heating, cooling and domestic hot-water operation are developed. Finally, the simulations obtained using TRNSYS are analysed and compared to experimental data, resulting in good agreement and thus the simulation models are validated.

Calin Sebarchievici; Ioan Sarbu

2015-01-01T23:59:59.000Z

79

Småskalig säsongslagring av solenergi för uppvärmning av bostäder; Small scale seasonal storage of solar energy for domestic heating.  

E-Print Network [OSTI]

?? The sun is a huge energy source with great potential of providing energy to the heating of homes and other buildings in an environmentally… (more)

Fryklund, Jenny

2010-01-01T23:59:59.000Z

80

Impact of heat transfer on the performance of micro gas turbines  

Science Journals Connector (OSTI)

Abstract The miniaturisation of gas turbine engines poses significant challenges to the performance in heat management due to the close proximity of the hot and cold components. This paper examines the scale and significance of heat transfer within micro gas turbines and aims to quantify the corresponding impacts on performance and efficiency. To study these effects, a reduced order lumped capacitance heat transfer network is developed. Two different micro turbine configurations are investigated and the effect of micro turbine size and material selection is explored. The investigation shows that the choice of configuration and materials influences the impact of heat transfer on the micro turbine performance and heat management is therefore key to achieving the full potential of micro turbines.

Dries Verstraete; Carlos Bowkett

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Natural Refrigerant High-Performance Heat Pump for Commercial Applications  

Broader source: Energy.gov [DOE]

Lead Performer: S-RAM - Franklin, TN Partners: -- Oak Ridge National Laboratory - Oak Ridge, TN -- Purdue University - West Lafayette, IN -- ReGen Power - Canning Vale 6155, Western Australia

82

Development of a High Performance Air Source Heat Pump for the US Market  

SciTech Connect (OSTI)

Heat pumps present a significant advantage over conventional residential heating technologies due to higher energy efficiencies and less dependence on imported oil. The US development of heat pumps dates back to the 1930 s with pilot units being commercially available in the 1950 s. Reliable and cost competitive units were available in the US market by the 1960 s. The 1973 oil embargo led to increased interest in heat pumps prompting significant research to improve performance, particularly for cold climate locations. Recent increasing concerns on building energy efficiency and environmental emissions have prompted a new wave of research in heat pump technology with special emphasis on reducing performance degradation at colder outdoor air temperatures. A summary of the advantages and limitations of several performance improvement options sought for the development of high performance air source heat pump systems for cold climate applications is the primary focus of this paper. Some recommendations for a high performance cold climate heat pump system design most suitable for the US market are presented.

Abdelaziz, Omar [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL; Gao, Zhiming [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Iu, Ipseng [ORNL] [ORNL

2011-01-01T23:59:59.000Z

83

Analysis of the Diagnostic Methods of the Performance Failure of Heating and Air Conditioning Systems  

E-Print Network [OSTI]

ICEBO2006, Shenzhen, China Co ntrol Systems for Energy Efficiency and Comfort, Vol. V-5-2 Analysis of the Diagnostic Methods of the Performance Failure of Heating and Air Conditioning Systems Lianyou LI Zhihong ZHANG Yong...

Li, L.; Zhang, Z.; Sun, Y.; Li, D.; Xie, H.

2006-01-01T23:59:59.000Z

84

High-Performance Thermoelectric Devices Based on Abundant Silicide Materials for Vehicle Waste Heat Recovery  

Broader source: Energy.gov [DOE]

Development of high-performance thermoelectric devices for vehicle waste heat recovery will include fundamental research to use abundant promising low-cost thermoelectric materials, thermal management and interfaces design, and metrology

85

Modeling of Performance, Cost, and Financing of Concentrating Solar, Photovoltaic, and Solar Heat Systems (Poster)  

SciTech Connect (OSTI)

This poster, submitted for the CU Energy Initiative/NREL Symposium on October 3, 2006 in Boulder, Colorado, discusses the modeling, performance, cost, and financing of concentrating solar, photovoltaic, and solar heat systems.

Blair, N.; Mehos, M.; Christiansen, C.

2006-10-03T23:59:59.000Z

86

Improving Process Heating System Performance: A Sourcebook for Industry, Second Edition  

Broader source: Energy.gov [DOE]

This sourcebook describes basic process heating applications and equipment, and outlines opportunities for energy and performance improvements. It also discusses the merits of using a systems approach in identifying and implementing these improvement opportunities. It is not intended to be a comprehensive technical text on improving process heating systems, but serves to raise awareness of potential performance improvement opportunities, provides practical guidelines, and offers suggestions on where to find additional help.

87

Register Closing Effects on Forced Air Heating System Performance  

SciTech Connect (OSTI)

Closing registers in forced air heating systems and leaving some rooms in a house unconditioned has been suggested as a method of quickly saving energy for California consumers. This study combined laboratory measurements of the changes in duct leakage as registers are closed together with modeling techniques to estimate the changes in energy use attributed to closing registers. The results of this study showed that register closing led to increased energy use for a typical California house over a wide combination of climate, duct leakage and number of closed registers. The reduction in building thermal loads due to conditioning only a part of the house was offset by increased duct system losses; mostly due to increased duct leakage. Therefore, the register closing technique is not recommended as a viable energy saving strategy for California houses with ducts located outside conditioned space. The energy penalty associated with the register closing technique was found to be minimized if registers furthest from the air handler are closed first because this tends to only affect the pressures and air leakage for the closed off branch. Closing registers nearer the air handler tends to increase the pressures and air leakage for the whole system. Closing too many registers (more than 60%) is not recommended because the added flow resistance severely restricts the air flow though the system leading to safety concerns. For example, furnaces may operate on the high-limit switch and cooling systems may suffer from frozen coils.

Walker, Iain S.

2003-11-01T23:59:59.000Z

88

Monitoring and simulation of the thermal performance of solar heated outdoor swimming pools  

SciTech Connect (OSTI)

Based on detailed measurements of two outdoor swimming pools (at Leonberg and Moehringen) a computer model has been developed and validated for the simulation of the thermal behaviour of such pools. The subroutine is compatible to TRNSYS 13.1. Correlations for the heat losses due to evaporation, convection, and radiation were taken from literature and tested in the model. It was not possible to select one optimal correlation for the description of the evaporative heat losses of both swimming pools due to the different exposure to wind. Using the most suitable correlation for the evaporative heat losses of each pool allowed for the simulation of the pool temperature with less than 0.5 K standard deviation between measured and simulated temperature. the major problem was the measurement of the relevant wind speed to be used in the correlations describing the evaporative heat losses under real outdoor conditions. A method is described detailing how to calibrate the model using the heating energy requirement and the measured pool temperature during actual operation periods. The analysis of the measured data of two different outdoor swimming pools under the same climatic conditions showed differences of a factor 2 and more in the heat demand per unit pool area. This was mainly caused by the difference in local wind speed which differed by more than a factor 4. The two pools investigated were heated by solar energy with a fraction of 28% and 14%, respectively, and the seasonal efficiency of the solar systems was 37.7% and 33.4%. Simulations show that a reduction of the water temperature from 24[degrees]C to 22[degrees]C during periods with low outdoor temperatures and few visitors, reduces the fuel consumption to less than half and increases the solar fraction from 28% to 50% in one pool.

Hahne, E.; Kuebler, R. (Universitaet Stuttgart (Germany))

1994-07-01T23:59:59.000Z

89

Performance analysis of mixed passive solar heating systems  

SciTech Connect (OSTI)

The various situations in which interactions between south-facing systems serving a single thermal zone may affect the performance of the mixture are discussed. In particular, the nature of direct gain interactions with unvented Trombe walls was explored using a detailed thermal network computer program. The results are compared with predictions from the simple design analysis procedures which neglect interactions. This comparison showed that system interactions can significantly improve the peformance of a mixture under certain conditions.

Wray, W.O.; Best, E.D.

1985-01-01T23:59:59.000Z

90

Experimental Study on Energy Efficiency of Heat-source Tower Heat Pump Units in Winter Condition  

Science Journals Connector (OSTI)

Building energy consumption in China has been increasing rapidly. And a small increase in the operation efficiency of the air-conditioning system can substantially decrease it. In this paper a new type heat pump is developed to improve the performance ... Keywords: Heat-source tower, Heat pump, Seasonal energy efficiency ratio(SEER), Hermal properties

Li Nianping; Zhang Wenjie; Wang Lijie; Liu Qiuke; Hu Jinhua

2011-01-01T23:59:59.000Z

91

Heat exchanger performance calculations for enhanced-tube condenser applications  

SciTech Connect (OSTI)

The lack of a prediction method is sometimes used for the rejection of enhanced tubes for some condenser applications even though there is ample data from single-tube condensing experiments. Three methods are discussed that can be used to rate and/or size these multitube units based on the single-tube experimental results. The Kern vertical-number correction appears to be quite adequate for most operating conditions, the exceptions being large sizes and/or deep vacuum operation. The bundle-factor method is preferred for these applications; however, field test results are required to obtain this factor. If performance data are not available, pointwise or numerical methods are required but special care must be taken to insure that the adverse effects of noncondensable gas pockets and the saturation-temperature depression are properly addressed.

Rabas, T.J.

1992-01-01T23:59:59.000Z

92

Heat exchanger performance calculations for enhanced-tube condenser applications  

SciTech Connect (OSTI)

The lack of a prediction method is sometimes used for the rejection of enhanced tubes for some condenser applications even though there is ample data from single-tube condensing experiments. Three methods are discussed that can be used to rate and/or size these multitube units based on the single-tube experimental results. The Kern vertical-number correction appears to be quite adequate for most operating conditions, the exceptions being large sizes and/or deep vacuum operation. The bundle-factor method is preferred for these applications; however, field test results are required to obtain this factor. If performance data are not available, pointwise or numerical methods are required but special care must be taken to insure that the adverse effects of noncondensable gas pockets and the saturation-temperature depression are properly addressed.

Rabas, T.J.

1992-07-01T23:59:59.000Z

93

PERFORMANCE EVALUATION OF AN AIR-TO-AIR HEAT PUMP COUPLED WITH TEMPERATE AIR-SOURCES INTEGRATED INTO A DWELLING  

E-Print Network [OSTI]

PERFORMANCE EVALUATION OF AN AIR-TO-AIR HEAT PUMP COUPLED WITH TEMPERATE AIR-SOURCES INTEGRATED.peuportier@mines-paristech.fr, Tel.: +33 1 40 51 91 51 ABSTRACT An inverter-driven air-to-air heat pump model has been developped capacity air-to-air heat pump coupled with temperate air sources (crawlspace, attic, sunspace, heat

Paris-Sud XI, Université de

94

Regional Variation in Residential Heat Pump Water Heater Performance in the United States  

Broader source: Energy.gov (indexed) [DOE]

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. Regional Variation in Residential Heat Pump Water Heater Performance in the US Jeff Maguire 4/30/13 Outline * Why HPWHs? * US Water Heating Market * Overview of HPWHs * Model Description * Results o HPWH Performance o Energy Savings Potential o Breakeven Cost 2 Heat Pump Water Heaters Save $300 a year over standard electric? Save $100 a year over standard gas? Heat Pump Electric Gas 3 Questions about HPWHs * Are HPWHs a good replacement for typical gas and electric storage water heaters? o In different locations across the country? o In conditioned/unconditioned space? o Source energy savings?

95

Heat transfer effects on the performance of an air-standard irreversible dual cycle  

Science Journals Connector (OSTI)

The objective of this study is to analyse the effects of heat transfer loss and internal irreversibilites, resulting from adiabatic processes, on an irreversible diesel heat engine. Thermodynamic optimisation has been carried out based on the Maximum Power (MP), Maximum Thermal Efficiency (MEF) and Maximum mean Effective Pressure (MEP) criteria for the dual cycle. Power output, thermal efficiency and mean effective pressure are obtained by introducing variable compression ratio, inlet temperature, combustion and heat transfer constants, and compression and expansion efficiencies. Optimal performance and design parameters of the dual cycle are obtained numerically for the MP, MEF and MEP conditions. The optimal compression ratio and pressure ratio at MEP conditions are compared with those results obtained by using the MP and MEF criteria for different constants of heat transfer and combustion in the characteristic grid curves. The results obtained in this paper may provide a guide to the performance and improvement of practical diesel engines.

Yasin Ust; Bahri Sahin; Hasan Kayhan Kayadelen; Guven Gonca

2013-01-01T23:59:59.000Z

96

Foundation Heat Exchanger Final Report: Demonstration, Measured Performance, and Validated Model and Design Tool  

SciTech Connect (OSTI)

Geothermal heat pumps, sometimes called ground-source heat pumps (GSHPs), have been proven capable of significantly reducing energy use and peak demand in buildings. Conventional equipment for controlling the temperature and humidity of a building, or supplying hot water and fresh outdoor air, must exchange energy (or heat) with the building's outdoor environment. Equipment using the ground as a heat source and heat sink consumes less non-renewable energy (electricity and fossil fuels) because the earth is cooler than outdoor air in summer and warmer in winter. The most important barrier to rapid growth of the GSHP industry is high first cost of GSHP systems to consumers. The most common GSHP system utilizes a closed-loop ground heat exchanger. This type of GSHP system can be used almost anywhere. There is reason to believe that reducing the cost of closed-loop systems is the strategy that would achieve the greatest energy savings with GSHP technology. The cost premium of closed-loop GSHP systems over conventional space conditioning and water heating systems is primarily associated with drilling boreholes or excavating trenches, installing vertical or horizontal ground heat exchangers, and backfilling the excavations. This project investigates reducing the cost of horizontal closed-loop ground heat exchangers by installing them in the construction excavations, augmented when necessary with additional trenches. This approach applies only to new construction of residential and light commercial buildings or additions to such buildings. In the business-as-usual scenario, construction excavations are not used for the horizontal ground heat exchanger (HGHX); instead the HGHX is installed entirely in trenches dug specifically for that purpose. The potential cost savings comes from using the construction excavations for the installation of ground heat exchangers, thereby minimizing the need and expense of digging additional trenches. The term foundation heat exchanger (FHX) has been coined to refer exclusively to ground heat exchangers installed in the overcut around the basement walls. The primary technical challenge undertaken by this project was the development and validation of energy performance models and design tools for FHX. In terms of performance modeling and design, ground heat exchangers in other construction excavations (e.g., utility trenches) are no different from conventional HGHX, and models and design tools for HGHX already exist. This project successfully developed and validated energy performance models and design tools so that FHX or hybrid FHX/HGHX systems can be engineered with confidence, enabling this technology to be applied in residential and light commercial buildings. The validated energy performance model also addresses and solves another problem, the longstanding inadequacy in the way ground-building thermal interaction is represented in building energy models, whether or not there is a ground heat exchanger nearby. Two side-by-side, three-level, unoccupied research houses with walkout basements, identical 3,700 ft{sup 2} floor plans, and hybrid FHX/HGHX systems were constructed to provide validation data sets for the energy performance model and design tool. The envelopes of both houses are very energy efficient and airtight, and the HERS ratings of the homes are 44 and 45 respectively. Both houses are mechanically ventilated with energy recovery ventilators, with space conditioning provided by water-to-air heat pumps with 2 ton nominal capacities. Separate water-to-water heat pumps with 1.5 ton nominal capacities were used for water heating. In these unoccupied research houses, human impact on energy use (hot water draw, etc.) is simulated to match the national average. At House 1 the hybrid FHX/HGHX system was installed in 300 linear feet of excavation, and 60% of that was construction excavation (needed to construct the home). At House 2 the hybrid FHX/HGHX system was installed in 360 feet of excavation, 50% of which was construction excavation. There are six pipes in all excavations (three par

Hughes, Patrick [ORNL; Im, Piljae [ORNL

2012-01-01T23:59:59.000Z

97

Comparison of Field Performance to Steady-State Performance for Two  

E-Print Network [OSTI]

efficiencies of these systems under field conditions. Steady-state performance data for individual heat pump reversal to defrost, by duty cycling, and by resort to electric resistance elements to supplement heating data on the seasonal performance of air-to-air residential heat pump systems. The purpose of this paper

Oak Ridge National Laboratory

98

Coefficient of performance (COP) analysis of geothermal district heating systems (GDHSs): Salihli GDHS case study  

Science Journals Connector (OSTI)

The purpose of this survey is about to analyze the heating coefficient of performance (COP) of geothermal district heating systems. Actual system data are taken from the Salihli GDHS, Turkey. The collected data are quantified and illustrated in tables, particularly for a reference temperature for comparison purposes. In this study, firstly energy and COP analysis of the \\{GDHSs\\} is introduced and then Salihli GDHS coefficient of performance results is given as a case study. Moreover, this paper offers an interesting empirical study of certain geothermal systems.

Leyla Ozgener

2012-01-01T23:59:59.000Z

99

Spray evaporation heat transfer performance in R-123 in tube bundles  

SciTech Connect (OSTI)

This study focuses on evaluating the heat transfer performance of refrigerant R-123 in the spray evaporation environment for pure refrigerant and for the case of lubricant addition. Tests were conducted with triangular-pitch tube bundles made from enhanced boiling tubes, enhanced condensation tubes, and plain-surface tubes. A second enhanced boiling surface tube bundle, made with a square-pitch tube alignment, was also tested so a comparison could be made between the square- and triangular-pitch geometries. In addition to pure refrigerant work, experiments were performed with small concentrations of a 305 SUS naphthenic mineral oil to evaluate its effect on falling-film heat transfer performance. Two different refrigerant supply rates were used in this work so the effects of film-feed supply rate could be interpreted from the data. Refrigerant was introduced to the test section via low-pressure-drop, wide-angle nozzles located directly over the tube bundle. Data were taken over a heat flux range of 40 kW/m{sup 2} (12,688 Btu/[h{center_dot}ft{sup 2}]) to 19 kW/m{sup 2} (6,027 Btu/[h{center_dot}ft{sup 2}]), while the refrigerant supply rate remained fixed. Collector tests were performed in parallel with the heat transfer experiments so the amount of refrigerant bypassing the tube bundle could be determined. It was found that the heat transfer coefficients were dependent upon film-feed supply rate, oil concentration, and heat flux. The enhanced boiling surface yielded higher heat transfer coefficients than either the enhanced condensation surface or the plain surface.

Moeykens, S. [Trane Co., LaCrosse, WI (United States); Kelly, J.E. [Kansas State Univ., Manhattan, KS (United States). Dept. of Mechanical Engineering; Pate, M.B. [Iowa State Univ., Ames, IA (United States). Mechanical Engineering Dept.

1996-12-31T23:59:59.000Z

100

Effect of electric field on heat transfer performance of automobile radiator at low frontal air velocity  

Science Journals Connector (OSTI)

The effect of electric field on the performance of automobile radiator is investigated in this work. In this experiment, a louvered fin and flat tube automobile radiator was mounted in a wind tunnel and there was heat exchange between a hot water stream circulating inside the tube and a cold air stream flowing through the external surface. The electric field was supplied on the airside of the heat exchanger and its supply voltage was adjusted from 0 kV to 12 kV. From the experiment, it was found that the unit with electric field pronounced better heat transfer rate, especially at low frontal velocity of air. The correlations for predicting the air-side heat transfer coefficient of the automobile radiator, with and without electric field, at low frontal air velocity were also developed and the predicted results agreed very well with the experimental data.

S. Vithayasai; T. Kiatsiriroat; A. Nuntaphan

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Active charge/passive discharge solar heating systems: thermal analysis and performance comparisons  

SciTech Connect (OSTI)

This study analyzes the performance of active charge/passive discharge solar space heating systems. This type of system combines liquid-cooled solar collector panels with a massive integral storage component that passively heats the building interior by radiation and free convection. The TRNSYS simulation program is used to evaluate system performance and to provide input for the development of a simplified analysis method. This method, which provides monthly calculations of delivered solar energy, is based on Klein's Phi-bar procedure and data from hourly TRNSYS simulations. The method can be applied to systems using a floor slab, a structural wall, or a water tank as the storage component. Important design parameters include collector area and orientation, building heat loss, collector and heat-exchanger efficiencies, storage capacity, and storage-to-room coupling. Performance simulation results are used for comparisons with active and passive solar designs. Economic comparisons are based on these data and additional system features, such as cooling augmentation and integration of heating components with structural members.

Swisher, J.

1981-06-01T23:59:59.000Z

102

Performance analysis of solar-assisted chemical heat-pump dryer  

SciTech Connect (OSTI)

A solar-assisted chemical heat-pump dryer has been designed, fabricated and tested. The performance of the system has been studied under the meteorological conditions of Malaysia. The system consists of four main components: solar collector (evacuated tubes type), storage tank, solid-gas chemical heat pump unit and dryer chamber. A solid-gas chemical heat pump unit consists of reactor, condenser and evaporator. The reaction used in this study (CaCl2-NH{sub 3}). A simulation has been developed, and the predicted results are compared with those obtained from experiments. The maximum efficiency for evacuated tubes solar collector of 80% has been predicted against the maximum experiment of 74%. The maximum values of solar fraction from the simulation and experiment are 0.795 and 0.713, respectively, whereas the coefficient of performance of chemical heat pump (COP{sup h}) maximum values 2.2 and 2 are obtained from simulation and experiments, respectively. The results show that any reduction of energy at condenser as a result of the decrease in solar radiation will decrease the coefficient of performance of chemical heat pump as well as decrease the efficiency of drying. (author)

Fadhel, M.I. [Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Faculty of Engineering and Technology, Multimedia University, Jalan Ayer Keroh Lama, 75450, Melaka (Malaysia); Sopian, K.; Daud, W.R.W. [Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2010-11-15T23:59:59.000Z

103

Performance of an optimally contact-cooled high-heat-load mirror at the APS.  

SciTech Connect (OSTI)

X-ray undulator beamlines at third-generation synchrotrons facilities use either a monochromator or a mirror as the first optical element. In this paper, the thermal and optical performance of an optimally designed contact-cooled high-heat-load x-ray mirror used as the first optical element on the 2ID undulator beamline at the Advanced Photon Source (APS) is reported. It is shown that this simple and economical mirror design can comfortably handle the high heat load of undulator beamlines and provide good performance with long-term reliability and ease of operation. Availability and advantages of such mirrors can make the mirror-first approach to high-heat-load beamline design an attractive alternative to monochromator-first beamlines in many circumstances.

Cai, Z.; Khounsary, A.; Lai, B.; McNulty, I.; Yun, W.

1998-11-18T23:59:59.000Z

104

Solar Colletors Combined with Ground-Source Heat Pumps in Dwellings - Analyses of System Performance.  

E-Print Network [OSTI]

??The use of ground-source heat pumps for heating buildings and domestic hot water in dwellings is increasing rapidly in Sweden. The heat pump extracts heat… (more)

Kjellsson, Elisabeth

2009-01-01T23:59:59.000Z

105

Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects  

E-Print Network [OSTI]

§1.4 – Heat Pipes for Waste Heat Recovery…..…………………………………analysis involving waste heat recovery of solar energyOverview of Industrial Waste Heat Recovery Technologies for

Armijo, Kenneth Miguel

2011-01-01T23:59:59.000Z

106

IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan ON SIDE REFRIGERANT MEASUREMENT OF HEAT PUMP  

E-Print Network [OSTI]

- 1 - 10th IEA Heat Pump Conference 2011, 16 - 19 May 2011, Tokyo, Japan ON SIDE REFRIGERANT MEASUREMENT OF HEAT PUMP SEASONAL PERFORMANCES C. T. Tran, PhD student, Centre for Energy and Processes, MINES, Research Engineer, ENERBAT, Electricity of France R&D, Moret/Loing, France Abstract Heat pump systems have

Paris-Sud XI, Université de

107

High temperature latent heat thermal energy storage: Phase change materials, design considerations and performance enhancement techniques  

Science Journals Connector (OSTI)

Abstract A very common problem in solar power generation plants and various other industrial processes is the existing gap between the period of thermal energy availability and its period of usage. This situation creates the need for an effective method by which excess heat can be stored for later use. Latent heat thermal energy storage is one of the most efficient ways of storing thermal energy through which the disparity between energy production or availability and consumption can be corrected, thus avoiding wastage and increasing the process efficiency. This paper reviews a series of phase change materials, mainly inorganic salt compositions and metallic alloys, which could potentially be used as storage media in a high temperature (above 300 °C) latent heat storage system, seeking to serve the reader as a comprehensive thermophysical properties database to facilitate the material selection task for high temperature applications. Widespread utilization of latent heat storage systems has been held back by the poor thermal conductivity and some other inherent drawbacks of the use of PCMs; this paper reviews several heat transfer and performance enhancement techniques proposed in the literature and discusses a number of design considerations that must be taken into account aiming to provide a broad overview for the design of high temperature latent heat based thermal energy storage systems.

Bruno Cárdenas; Noel León

2013-01-01T23:59:59.000Z

108

Field Study of Performance, Comfort, and Sizing of Two Variable-Speed Heat Pumps Installed in a Single 2-Story Residence  

SciTech Connect (OSTI)

With the recent advancements in the application of variable-speed (VS) compressors to residential HVAC systems, opportunities are now available to size heat pumps (HPs) to more effectively meet heating and cooling loads in many of the climate zones in the US with limited use of inefficient resistance heat. This is in contrast to sizing guidance for traditional single-speed HPs that limits the ability to oversize with regard to cooling loads, because of risks of poor dehumidification during the cooling season and increased cycling losses. VS-drive HPs can often run at 30-40% of their rated cooling capacity to reduce cycling losses, and can adjust fan speed to provide better indoor humidity control. Detailed air-side performance data was collected on two VS-drive heat pumps installed in a single unoccupied research house in Knoxville, TN, a mixed-humid climate. One system provided space conditioning for the upstairs, while the other unit provided space conditioning for the downstairs. Occupancy was simulated by operating the lights, shower, appliances, other plug loads, etc. to simulate the sensible and latent loads imposed on the building space by internal electric loads and human occupants according to the Building America Research Benchmark (2008). The seasonal efficiency and energy use of the units are calculated. Annual energy use is compared to that of the single speed minimum efficiency HPs tested in the same house previously. Sizing of the units relative to the measured building load and manual J design load calculations is examined. The impact of the unit sizing with regards to indoor comfort is also evaluated.

Munk, Jeffrey D [ORNL; Odukomaiya, Adewale O [ORNL; Gehl, Anthony C [ORNL; Jackson, Roderick K [ORNL

2014-01-01T23:59:59.000Z

109

Influence of the heat storage size on the plant performance in a Smart User case study  

Science Journals Connector (OSTI)

The increasing diffusion of renewable energy sources are posing new challenges to the power grid due to their intrinsic unpredictability causing poor power quality, line congestion and unreliable and unsecure grid operations. In the future, power grid operators may require to the customers/producers a prescribed exchange profile, leading to a diffusion of storage systems or prime movers (especially small combined heat and power for distributed resources) able to balance renewable sources fluctuations. In this latter case, one of the major issue is the efficient use of the heat co-generated: the adoption of thermal storages appears to be necessary. In this paper, the energy performance of a Smart User, i.e. a dwelling with renewable energy sources, a combined cooling, heat, and power system, and heat and cooling back-up generators, is estimated by means of a purposely developed TRNSYS unsteady model. A virtual stand-alone operating condition is imposed for the analysed building as an arbitrary profile of power exchange with the grid. The balancing of renewable sources fluctuations imposes a non-negligible part of the heat from the prime mover to be wasted and a sensible consumption for auxiliary devices (i.e. the auxiliary boiler and the compression chiller). By applying a thermal storage, and increasing its capacity, the fraction of heat wasted and the supply from other devices is remarkably changed, showing different plant performance and efficiencies. The Smart User primary energy consumptions of the different configurations are compared to several options, showing appreciable differences in the performance.

Andrea Chesi; Giovanni Ferrara; Lorenzo Ferrari; Sandro Magnani; Fabio Tarani

2013-01-01T23:59:59.000Z

110

Comparative performance evaluation of cascaded air-source hydronic heat pumps  

Science Journals Connector (OSTI)

Abstract The results are reported of an investigation of the effects of cascading air-source heat pumps on performance for hydronic residential systems. Three heat pump systems are modeled as single-stage, single-refrigerant cascaded, and two-refrigerant cascaded. Energy and exergy analyses are performed, and a comparative performance analysis is carried out, considering energy efficiency, refrigerant mass flow rates, evaporator pressure, exergy efficiency, and several other criteria. Three sets of source and supply temperatures, representing different climates and different water sink systems (low, medium and high temperature), are used to provide more comprehensive behavior assessments of the systems. Additionally, the optimum intermediate pressure of the cascaded systems for all working temperature pairs is found for the highest energetic COP and exergetic COP. Compared to a single stage heat pump, cascading improves the overall energy efficiency of the system for low-ambient temperatures, but not for high-ambient temperatures. Although this improvement is minor, the exergetic COP is increased by 67% for the single refrigerant cascaded system and 70% for a two-refrigerant cascaded system, at low ambient temperatures. Using refrigerant R404A in the low-pressure cycle marginally improves the energetic COP of the cascaded heat pump, but increases the evaporator working pressure, making it possible to use smaller compressors. However, the overall refrigerant mass flow rates increase with cascading. The two cascaded systems have higher exergy destructions (by almost four times) compared to the single stage system, mainly due to having more components, including an intermediate heat exchanger. Also, cascading shifts the major exergy destruction centers from the compressors and expansion valves to the evaporators. A comparison of cascaded and single-stage heat pumps shows that the exergy analysis results exhibit a different trend than energy analysis results with source and supply temperatures, highlighting the advantages of exergy methods in determining if cascading is appropriate for a given application.

R. Soltani; I. Dincer; M.A. Rosen

2015-01-01T23:59:59.000Z

111

Statistical comparison of ICRF and NBI heating performance in JET-ILW L-mode plasmas  

SciTech Connect (OSTI)

After the change over from the C-wall to the ITER-like Be/W wall (ILW) in JET, the radiation losses during ICRF heating have increased and are now substantially larger than those observed with NBI at the same power levels, in spite of the similar global plasma energies reached with the two heating systems. A comparison of the NBI and ICRF performances in the JET-ILW experiments, based on a statistical analysis of ?3000 L-mode discharges, will be presented.

Lerche, E.; Van Eester, D. [Association EURATOM-Belgian State, LPP-ERM-KMS, TEC partner, Brussels (Belgium); Jacquet, Ph.; Mayoral, M.-L.; Graham, M.; Matthews, G.; Monakhov, I.; Rimini, F. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Bobkov, V.; Neu, R.; Puetterich, T. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Czarnecka, A. [Association Euratom-IPPLM, Hery 23, 01-497 Warsaw (Poland); Vries, P. de [FOM Institute DIFFER, Euratom Association, P.O. Box 1207, Nieuwegein (Netherlands); Collaboration: JET-EFDA Contributors

2014-02-12T23:59:59.000Z

112

Performance investigation of a cogeneration plant with the efficient and compact heat recovery system  

Science Journals Connector (OSTI)

This paper presents the performance investigation of a cogeneration plant equipped with an efficient waste heat recovery system. The proposed cogeneration system produces four types of useful energy namely: (i) electricity (ii) steam (iii) cooling and (iv) dehumidification. The proposed plant comprises a Capstone C30 micro-turbine which generates 24 kW of electricity a compact and efficient waste heat recovery system and a host of waste heat activated devices namely (i) a steam generator (ii) an absorption chiller (iii) an adsorption chiller and (iv) a multi-bed desiccant dehumidifier. The numerical analysis for the host of waste heat recovery system and thermally activated devices using FORTRAN power station linked to powerful IMSL library is performed to investigate the performance of the overall system. A set of experiments both part load and full load of micro-turbine is conducted to examine the electricity generation and the exhaust gas temperature. It is observed that energy utilization factor (EUF) could achieve as high as 70% while Fuel Energy Saving Ratio (FESR) is found to be 28%.

2012-01-01T23:59:59.000Z

113

Study on Performance Verification and Evaluation of District Heating and Cooling System Using Thermal Energy of River Water  

E-Print Network [OSTI]

September 16, 2014 NIKKEN SEKKEI Research Institute Naoki Takahashi Study on Performance Verification and Evaluation of District Heating and Cooling System Using Thermal Energy of River Water ESL-IC-14-09-19 Proceedings of the 14th International... of the 14th International Conference for Enhanced Building Operations, Beijing, China, September 14-17, 2014 District heating and cooling system in Nakanoshima 4 Characteristics of heat supply plant in Nakanoshima district -River water is utilized as heat...

Takahashi,N.; Niwa, H.; Kawano,M.; Koike,K.; Koga,O.; Ichitani, K.; Mishima,N.

2014-01-01T23:59:59.000Z

114

Field Performance of Heat Pump Water Heaters in the Northeast, Massachusetts and Rhode Island (Fact Sheet)  

SciTech Connect (OSTI)

Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads. Steven Winter Associates, Inc. embarked on one of the first in situ studies of these newly released HPWH products through a partnership with two sponsoring electric utility companies, National Grid and NSTAR, and one sponsoring energy efficiency service program administrator, Cape Light Compact. Recent laboratory studies have measured performance of HPWHs under various operating conditions, but publicly available field studies have not been as available. This evaluation attempts to provide publicly available field data on new HPWHs by monitoring the performance of three recently released products (General Electric GeoSpring, A.O. Smith Voltex, and Stiebel Eltron Accelera 300). Fourteen HPWHs were installed in Massachusetts and Rhode Island and monitored for over a year. Of the 14 units, ten were General Electric models (50 gallon units), two were Stiebel Eltron models (80 gallon units), and two were A.O. Smith models (one 60-gallon and one 80-gallon unit).

Not Available

2013-12-01T23:59:59.000Z

115

Operational Performance Results of an Innovative Solar Thermal Cooling and Heating Plant  

Science Journals Connector (OSTI)

Solar thermal cooling and heating plants with single-effect sorption chillers/heat pumps promise primary energy savings compared to electric vapor compression chiller systems. Yet, the need of auxiliary electric a nd fossil energy for the operation and backup of the thermal cooling system possibly worsen the primary energy balance. An auspicious approach to overcome this problem is the application of a more efficient multi -stage sorption chiller with flexible operational modes. A pilot installation of that innovative solar thermal heating and cooling plant comprising a two stage absorption chiller/heat pump is presented. Beginning with the motivation and the system concept, a detailed analysis of the 2011/2012 cooling and heating periods is shown. The influence of the different system components – especially the absorption chiller – on the overall system performance is analyzed and a comparison to data from a detailed dynamic model is carried out. Recommendations for the improvement with respect to efficiency and economic aspects are given based on the installation process and the operational experience gained in the last 1 ½ years.

Manuel Riepl; Felix Loistl; Richard Gurtner; Martin Helm; Christian Schweigler

2012-01-01T23:59:59.000Z

116

Performance investigation of the Afyon geothermal district heating system for building applications: Exergy analysis  

Science Journals Connector (OSTI)

This paper deals with an energy and exergy evaluation and modeling of geothermal district heating systems for their system analysis, performance evaluation and optimization. As a comprehensive case study, the Afyon geothermal district heating system (AFJET) in Afyon, Turkey is considered and actual thermal data are collected and employed for analysis. Using actual system data, an evaluation of the district heating system performance, energy and exergy efficiencies, and exergy destructions in the system are conducted in this regard. This study is also conducted to show how energy and exergy efficiencies of the \\{GDHSs\\} will change with the reference temperature and how exergy losses will affect by the temperature difference between the geothermal resource and the supply temperature of the district heating distribution network. In addition, the negative effects of discharge waters of the AFJET are presented. The energy and exergy efficiencies of the entire AFJET are found to be 37.59% and 47.54%, respectively. The results are expected to be helpful to researchers and engineers in the area.

Ali Keçeba?; Muhammet Kayfeci; Engin Gedik

2011-01-01T23:59:59.000Z

117

Performance of Heat Pump Water Heaters: Initial Findings of Draw Profile Effect on HPWH Efficiency  

Broader source: Energy.gov (indexed) [DOE]

Performance of Heat Pump Water Heaters Performance of Heat Pump Water Heaters © 2011 Steven Winter Associates, Inc. All rights reserved. © 2011 Steven Winter Associates, Inc. All rights reserved. Evaluation Overview  2000-2002 Evaluated 20 installations with CL&P  Product had problems; not ready for prime time (average COPs of 1.67 was not the problem)  New batch of heaters available, including:  GE's GeoSpring Hybrid (50 gal)  A.O.Smith's Voltex Hybrid (60 & 80 gal)  Stiebel-Eltron's Accelera 300 (80 gal)  Evaluating 14 installations for National Grid, NSTAR, & Cape Light Compact. © 2011 Steven Winter Associates, Inc. All rights reserved. © 2011 Steven Winter Associates, Inc. All rights reserved.

118

Combined cooling, heating and power: A review of performance improvement and optimization  

Science Journals Connector (OSTI)

Abstract This paper presents a review on combined cooling, heating, and power (CCHP) systems. This work summarizes the methods used to perform energetic and exergetic analyses, system optimization, performance improvement studies, and development and analysis of CCHP systems, as reported in existing literature. In addition, this work highlights the most current research and emerging trends in CCHP technologies. It is envisioned that the information collected in this review paper will be a valuable source of information, for researchers, designers, and engineers, and provides direction and guidance for future research in CCHP technology.

Heejin Cho; Amanda D. Smith; Pedro Mago

2014-01-01T23:59:59.000Z

119

Substations for Decentralized Solar District Heating: Design, Performance and Energy Cost  

Science Journals Connector (OSTI)

Abstract The development of solar district heating is gaining more and more interest, but, in some case the space available for the integration of solar collectors on the ground is limited and the use of decentralized systems is necessary. For decentralized solar district heating systems different hydraulic schemes at the substation level, with or without local use of solar energy, are possible. The present paper detailed an advanced study on decentralized solar district heating system using dynamic simulation software. Nine different hydraulic schemes for substations have been investigated with a return to return feed in. For each scheme many parameters that influence the performance of the solar installation have been studied such as the district heating network return temperature, the solar collector area and the type of solar collector (low temperature or high temperature solar collector). The comparison between the different hydraulic schemes is based on thermal efficiency but also on solar energy cost using the methodology of the Levelized Cost Of Energy (LCOE).

Cedric Paulus; Philippe Papillon

2014-01-01T23:59:59.000Z

120

Prediction modeling of physiological responses and human performance in the heat  

Science Journals Connector (OSTI)

Over the last two decades, our laboratory has been establishing the data base and developing a series of predictive equations for deep body temperature, heart rate and sweat loss responses of clothed soldiers performing physical work at various environmental extremes. Individual predictive equations for rectal temperature, heart rate and sweat loss as a function of the physical work intensity, environmental conditions and particular clothing ensemble have been published in the open literature. In addition, important modifying factors such as energy expenditure, state of heat acclimation and solar heat load have been evaluated and appropriate predictive equations developed. Currently, we have developed a comprehensive model which is programmed on a Hewlett-Packard 41 CV hand held calculator. The primary physiological inputs are deep body (rectal) temperature and sweat loss while the predicted outputs are the expected physical work-rest cycle, the maximum single physical work time if appropriate, and the associated water requirements. This paper presents the mathematical basis employed in the development of the various individual predictive equations of our heat stress model. In addition, our current heat stress prediction model as programmed on the HP 41 CV is discussed from the standpoint of propriety in meeting the Army's needs and therefore assisting in military mission accomplishment.

Kent B. Pandolf; Leander A. Stroschein; Lawrence L. Drolet; Richard R. Gonzalez; Michael N. Sawka

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" from the National Library of EnergyBeta (NLEBeta).
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121

Device and method for measuring the coefficient of performance of a heat pump  

DOE Patents [OSTI]

A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistance heaters. Temperature sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct temperatures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electronics is required to operate the instrument.

Brantley, Vanston R. (Knoxville, TN); Miller, Donald R. (Kingston, TN)

1984-01-01T23:59:59.000Z

122

Energetic and exergetic performance investigation of the Bigadic Geothermal District Heating System in Turkey  

Science Journals Connector (OSTI)

In this study a comprehensive performance analysis of the Bigadic Geothermal District Heating System (GDHS) in Balikesir, Turkey is performed through thermodynamic assessment in terms of energy and exergy efficiencies. The actual thermal data taken from the Technical Department of the GDHS are utilized in the analysis to determine the exergy destructions in each component of the system and the overall energy and exergy efficiencies of the system for two reference temperatures taken as 15.6 °C for November (e.g., case 1) and 11 °C for December (e.g., case 2). The energy and exergy flow diagrams are clearly drawn to illustrate how much destructions/losses take place in addition to the inputs and outputs. The average energy and exergy efficiencies are found to be 30% and 36% for case 1, and 40% and 49% for case 2, respectively. The key reason as to why the exergy efficiencies are higher is because the heat recovery option is used through the reinjection processes which make use of waste heat. A parametric study is also conducted to show how energy and exergy flows change with the environment temperature. The results are expected to be helpful to researchers and engineers in the area.

Z. Oktay; C. Coskun; I. Dincer

2008-01-01T23:59:59.000Z

123

Device and method for measuring the coefficient of performance of a heat pump  

DOE Patents [OSTI]

A method and instrument is provided which allows quick and accurate measurement of the coefficient of performance of an installed electrically powered heat pump including auxiliary resistane heaters. Temperature-sensitive resistors are placed in the return and supply air ducts to measure the temperature increase of the air across the refrigerant and resistive-heating elements of the system. The voltages across the resistors which are directly proportional to the respective duct tempertures are applied to the inputs of a differential amplifier so that its output voltage is proportional to the temperature difference across the unit. A voltage-to-frequency converter connected to the output of the differential amplifier converts the voltage signal to a proportional-frequency signal. A digital watt meter is used to measure the power to the unit and produces a signal having a frequency proportional to the input power. A digital logic circuit ratios the temperature difference signal and the electric power input signal in a unique manner to produce a single number which is the coefficient of performance of the unit over the test interval. The digital logic and an in-situ calibration procedure enables the instrument to make these measurements in such a way that the ratio of heat flow/power input is obtained without computations. No specialized knowledge of thermodynamics or electrons is required to operate the instrument.

Brantley, V.R.; Miller, D.R.

1982-05-18T23:59:59.000Z

124

A Tool for Life Cycle Climate Performance (LCCP) Based Design of Residential Air Source Heat Pumps  

SciTech Connect (OSTI)

A tool for the design of air source heat pumps (ASHP) based on their life cycle climate performance (LCCP) analysis is presented. The LCCP model includes direct and indirect emissions of the ASHP. The annual energy consumption of the ASHP is determined based on AHRI Standard 210/240. The tool can be used as an evaluation tool when the user inputs the required performance data based on the ASHP type selected. In addition, this tool has system design capability where the user inputs the design parameters of the different components of the heat pump and the tool runs the system simulation software to calculate the performance data. Additional features available in the tool include the capability to perform parametric analysis and sensitivity study on the system. The tool has 14 refrigerants, and 47 cities built-in with the option for the user to add more refrigerants, based on NIST REFPROP, and cities, using TMY-3 database. The underlying LCCP calculation framework is open source and can be easily customized for various applications. The tool can be used with any system simulation software, load calculation tool, and weather and emissions data type.

Beshr, Mohamed [University of Maryland, College Park; Aute, Vikrant [University of Maryland, College Park; Abdelaziz, Omar [ORNL; Fricke, Brian A [ORNL; Radermacher, Reinhard [University of Maryland, College Park

2014-01-01T23:59:59.000Z

125

Design Approach and Performance Analysis of a Small Integrated Heat Pump (IHP) for Net Zero Energy Homes (ZEH)  

SciTech Connect (OSTI)

This paper describes the design and performance analysis of a variable-capacity heat pump system developed for a small [1800ft2 (167 m2)] prototype net ZEH with an average design cooling load of 1.25 tons (4.4 kW) in five selected US climates. The heat pump integrates space heating and cooling, water heating, ventilation, and humidity control (humidification and dehumidification) functions into a single integrated heat pump (IHP) unit. The design approach uses one small variable-capacity compressor to meet all the above functions in an energy efficient manner. Modal performance comparisons to an earlier IHP product are shown relative to the proposed new design for net ZEH application. The annual performance analysis approach using TRNSYS in conjunction with the ORNL Heat Pump Design Model is discussed. Annual performance projections for a range of locations are compared to those of a base system consisting of separate pieces of equipment to perform the same functions. The ZEH IHP is projected to reduce energy use for space heating & cooling, water heating, dehumidification, and ventilation for a net ZEH by about 50% compared to that of the base system.

Rice, C Keith [ORNL; Murphy, Richard W [ORNL; Baxter, Van D [ORNL

2008-01-01T23:59:59.000Z

126

Monitored performance of residential geothermal heat pumps in central Texas and Southern Michigan  

SciTech Connect (OSTI)

This report summarizes measured performance of residential geothermal heat pumps (GHP`s) that were installed in family housing units at Ft. Hood, Texas and at Selfridge Air National Guard base in Michigan. These units were built as part of a joint Department of Defense/Department of Energy program to evaluate the energy savings potential of GHP`s installed at military facilities. At the Ft. Hood site, the GHP performance was compared to conventional forced air electric air conditioning and natural gas heating. At Selfridge, the homes under test were originally equipped with electric baseboard heat and no air conditioning. Installation of the GHP systems at both sites was straightforward but more problems and costs were incurred at Selfridge because of the need to install ductwork in the homes. The GHP`s at both sites produced impressive energy savings. These savings approached 40% for most of the homes tested. The low cost of energy on these bases relative to the incremental cost of the GHP conversions precludes rapid payback of the GHP`s from energy savings alone. Estimates based on simple payback (no inflation and no interest on capital) indicated payback times from 15 to 20 years at both sites. These payback times may be reduced by considering the additional savings possible due to reduced maintenance costs. Results are summarized in terms of 15 minute, hourly, monthly, and annual performance parameters. The results indicate that all the systems were working properly but several design shortcomings were identified. Recommendations are made for improvements in future installations at both sites.

Sullivan, W.N.

1997-11-01T23:59:59.000Z

127

Numerical Study on the Operating Performance of an Indirect Expansion Solar Assisted Multifunctional Heat Pump in Water Heating Mode  

Science Journals Connector (OSTI)

An indirect expansion solar assisted multifunctional heat pump (IE-SAMHP) is ... SAMHP consists of an all-glass evacuated-tube solar collector system, a compressor, two air-...

Ji Jie; Jiang Aiguo; Yang Jichun; Pei Gang…

2009-01-01T23:59:59.000Z

128

Numerical simulation of heat transfer performance of an air-cooled steam condenser in a thermal power plant  

Science Journals Connector (OSTI)

Numerical simulation of the thermal-flow characteristics and heat transfer performance is made of an air-cooled steam condenser (ACSC) in a thermal power plant by considering the effects of ambient wind speed and...

Xiufeng Gao; Chengwei Zhang; Jinjia Wei; Bo Yu

2009-09-01T23:59:59.000Z

129

Dynamic Performance Study on the Solar Collector/Evaporator of Direct Expansion Solar Assisted Heat Pump Systems  

Science Journals Connector (OSTI)

A dynamic simulation model is developed for predicting performance of the solar collector/evaporator of direct expansion solar assisted heat pump systems. In this model, ... meteorological and configuration param...

Li Hong; Yang Hongxing

2009-01-01T23:59:59.000Z

130

Measured Space Conditioning and Water Heating Performance of a Ground-Source Integrated Heat Pump in a Residential Application  

SciTech Connect (OSTI)

In an effort to reduce residential building energy consumption, a ground-source integrated heat pump was developed to meet a home s entire space conditioning and water heating needs, while providing 50% energy savings relative to a baseline suite of minimum efficiency equipment. A prototype 7.0 kW system was installed in a 344 m2 research house with simulated occupancy in Oak Ridge, TN. The equipment was monitored from June 2012 through January 2013.

Munk, Jeffrey D [ORNL] [ORNL; Ally, Moonis Raza [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Gehl, Anthony C [ORNL] [ORNL

2014-01-01T23:59:59.000Z

131

Thermal Performance of Microencapsulated Phase Material (MPCM) Slurry in a Coaxial Heat Exchanger  

E-Print Network [OSTI]

Microencapsulated phase change material (MPCM) slurries and coil heat exchangers had been recently studied separately as enhancers of convective heat transfer processes. Due to the larger apparent heat related to the phase change process...

Yu, Kun

2014-05-08T23:59:59.000Z

132

Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects  

E-Print Network [OSTI]

and solar concentration, for a gravity-assisted heat pipevs. solar concentration with a gravity-assisted heat pipe inand solar concentration, for a gravity-assisted heat pipe

Armijo, Kenneth Miguel

2011-01-01T23:59:59.000Z

133

Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects  

E-Print Network [OSTI]

on a flat-plate solar heat collector with integrated solarBinary Mixture Nucleate Boiling Heat Transfer CorrelationsG.E. , 1965, “A study of heat transfer in nucleate pool

Armijo, Kenneth Miguel

2011-01-01T23:59:59.000Z

134

Performance evaluation of an Organic Rankine Cycle (ORC) for power applications from low grade heat sources  

Science Journals Connector (OSTI)

Abstract In this paper the performance of an Organic Rankine Cycle (ORC) module, which was designed and built for a specific power application, is experimentally characterized. The ORC tested satisfies the main specifications for an efficient power system, highlighting a volumetric expander with large built-in volume ratio. For tests development, a monitored test bench has been used and adapted to the planned test procedure, which consisted of varying the thermal power input for different condensing conditions. Thereby, 10 steady state points are achieved and analyzed according to thermal power input, gross and net electrical powers, electrical cycle efficiencies and expander effectiveness. The results show that the ORC performances are improved for higher thermal oil temperatures, capturing more thermal power, producing more electricity and achieving better cycle efficiencies. The maximum gross electrical efficiency obtained is 12.32%, for a heat source temperature about 155 °C and a direct dissipation to the ambient. Moreover, the expander reaches an electrical isentropic effectiveness about 65% for an optimum pressure ratio around 7, being a suitable system for power applications from low grade heat sources.

Bernardo Peris; Joaquín Navarro-Esbrí; Francisco Molés; Roberto Collado; Adrián Mota-Babiloni

2014-01-01T23:59:59.000Z

135

Thermal performance analysis of a direct-expansion solar-assisted heat pump water heater  

Science Journals Connector (OSTI)

A direct-expansion solar-assisted heat pump water heater (DX-SAHPWH) is described, which can supply hot water for domestic use during the whole year. The system mainly employs a bare flat-plate collector/evaporator with a surface area of 4.2 m2, an electrical rotary-type hermetic compressor, a hot water tank with the volume of 150 L and a thermostatic expansion valve. R-22 is used as working fluid in the system. A simulation model based on lumped and distributed parameter approach is developed to predict the thermal performance of the system. Given the structure parameters, meteorological parameters, time step and final water temperature, the numerical model can output operational parameters, such as heat capacity, system COP and collector efficiency. Comparisons between the simulation results and the experimental measurements show that the model is able to give satisfactory predictions. The effect of various parameters, including solar radiation, ambient temperature, wind speed and compressor speed, has been analyzed on the thermal performance of the system.

X.Q. Kong; D. Zhang; Y. Li; Q.M. Yang

2011-01-01T23:59:59.000Z

136

Experimental and numerical investigation on air-side performance of fin-and-tube heat exchangers with various fin patterns  

SciTech Connect (OSTI)

Air-side heat transfer and friction characteristics of five kinds of fin-and-tube heat exchangers, with the number of tube rows (N = 12) and the diameter of tubes (D{sub o} = 18 mm), have been experimentally investigated. The test samples consist of five types of fin configurations: crimped spiral fin, plain fin, slit fin, fin with delta-wing longitudinal vortex generators (VGs) and mixed fin with front 6-row vortex-generator fin and rear 6-row slit fin. The heat transfer and friction factor correlations for different types of heat exchangers were obtained with the Reynolds numbers ranging from 4000 to 10000. It was found that crimped spiral fin provides higher heat transfer and pressure drop than the other four fins. The air-side performance of heat exchangers with the above five fins has been evaluated under three sets of criteria and it was shown that the heat exchanger with mixed fin (front vortex-generator fin and rear slit fin) has better performance than that with fin with delta-wing vortex generators, and the slit fin offers best heat transfer performance at high Reynolds numbers. Based on the correlations of numerical data, Genetic Algorithm optimization was carried out, and the optimization results indicated that the increase of VG attack angle or length, or decrease of VG height may enhance the performance of vortex-generator fin. The heat transfer performances for optimized vortex-generator fin and slit fin at hand have been compared with numerical method. (author)

Tang, L.H.; Zeng, M.; Wang, Q.W. [State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)

2009-07-15T23:59:59.000Z

137

Performance Test and Energy Saving Analysis of a Heat Pipe Dehumidifier  

E-Print Network [OSTI]

Heat pipe technology applied to ventilation, dryness, and cooling and heating radiator in a building is introduced in this paper. A new kind of heat pipe dehumidifier is designed and tested. The energy-saving ratio with the heat pipe dehumidifier...

Zhao, X.; Li, Q.; Yun, C.

2006-01-01T23:59:59.000Z

138

Solar Assisted Heat Pump Systems with Ground Heat Exchanger – Simulation Studies  

Science Journals Connector (OSTI)

Abstract Different concepts of solar assisted heat pump systems with ground heat exchanger are simulated according to IEA SHC Task44/HPP Annex38 reference conditions. Two aspects of the concepts are investigated using TRNSYS simulations. First, the solar impact on system efficiency is assessed by the seasonal performance factor. Second, the solar impact on the possible shortening of the ground heat exchanger is evaluated by the minimum temperature at the ground heat exchanger inlet. The simulation results reveal diverging optimums for the concepts. The direct use of solar energy clearly achieves the best effect on the efficiency improvement. A simple domestic hot water system reaches a seasonal performance factor of 4.5 and solar combi-systems seasonal performance factors up to 6. In contrast, the use of solar energy on the cold side of the heat pump achieves the best effects on the shortening of the ground heat exchanger of up to 20%. Two highly sensitive influences are investigated with the developed transient system model. First, the minimum allowed heat source temperature is varied. Here 1 K equals a variation of 0.25 in the seasonal performance or of around 10% ground heat exchanger length. Second, the ground heat exchanger model is simulated without and with a pre-pipe that improves the transient model behavior. The influence of this pre-pipe on the SPF is small for conventionally designed ground heat exchangers, but of around 2 K for the minimum inlet temperature. Therefore, the dynamic model quality reveals potential to reduce the size of the ground heat exchanger corresponding to investment costs.

Erik Bertram

2014-01-01T23:59:59.000Z

139

Direct expansion solar assisted heat pumps – A clean steady state approach for overall performance analysis  

Science Journals Connector (OSTI)

Abstract Traditional thermal solar panel technologies have limited efficiency and the required economic investments make them noncompetitive in the space heating market. The greatest limit to the diffusion of thermal solar systems is the characteristic temperatures they can reach: the strong connection between the user temperature and the collector temperature makes it possible to achieve high thermal (collector) efficiency only at low, often useless, user temperatures. By using solar collectors as thermal exchange units (evaporators) in a heat pump system (direct expansion solar assisted heat pump, DX-SAHP), the overall efficiency greatly increases with a significative cut of the associated investment in terms of pay-back time. In this study, an approach is proposed to the steady state analysis of DX-SAHP, which is based on the simplified inverse Carnot cycle and on the second law efficiency concept. This method, without the need of calculating the refrigerant fluid properties and the detailed processes occurring in the refrigeration device, allows us to link the main features of the plant to its relevant interactions with the surroundings. The very nature of the proposed method makes the relationship explicit and meaningful among all the involved variables. The paper, after the description of the method, presents an explanatory application of this technique by reviewing various aspects of the performance of a typical DX-SAHP in which the savings on primary energy consumption is regarded as the main feature of the plant and highlighted in a monthly averaged analysis. Results agree to those coming from a common standard steady state thermodynamic analysis. The application to a typical DX-SAHP system demonstrates that a mean saved primary energy of about 50% with respect to standard gas burner can be achieved for the same user needs. Such a result is almost independent from the type of flat plate solar panel used (double or single glazed, or even bare panels) as a result of using an optimal collector working temperature.

Luca A. Tagliafico; Federico Scarpa; Federico Valsuani

2014-01-01T23:59:59.000Z

140

High Performance Catalytic Heat Exchanger for SOFC Systems - FuelCell Energy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Catalytic Heat Catalytic Heat Exchanger for SOFC Systems-FuelCell Energy Background In a typical solid oxide fuel cell (SOFC) power generation system, hot (~900 °C) effluent gas from a catalytic combustor serves as the heat source within a high-temperature heat exchanger, preheating incoming fresh air for the SOFC's cathode. The catalytic combustor and the cathode air heat exchanger together represent the largest opportunity for cost

Note: This page contains sample records for the topic "heating season performance" 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

Heat transfer and thermodynamic performance of a parabolic trough receiver with centrally placed perforated plate inserts  

Science Journals Connector (OSTI)

Abstract In this paper, a numerical investigation of thermal and thermodynamic performance of a receiver for a parabolic trough solar collector with perforated plate inserts is presented. The analysis was carried out for different perforated plate geometrical parameters including dimensionless plate orientation angle, the dimensionless plate spacing, and the dimensionless plate diameter. The Reynolds number varies in the range 1.02 × 104 ? Re ? 7.38 × 105 depending on the heat transfer fluid temperature. The fluid temperatures used are 400 K, 500 K, 600 K and 650 K. The porosity of the plate was fixed at 0.65. The study shows that, for a given value of insert orientation, insert spacing and insert size, there is a range of Reynolds numbers for which the thermal performance of the receiver improves with the use of perforated plate inserts. In this range, the modified thermal efficiency increases between 1.2% and 8%. The thermodynamic performance of the receiver due to inclusion of perforated plate inserts is shown to improve for flow rates lower than 0.01205 m3/s. Receiver temperature gradients are shown to reduce with the use of inserts. Correlations for Nusselt number and friction factor were also derived and presented.

Aggrey Mwesigye; Tunde Bello-Ochende; Josua P. Meyer

2014-01-01T23:59:59.000Z

142

INFORMAL REPORT PROPERTIES AND PERFORMANCE OF CEMENT- BASED GROUTS FOR GEOTHERMAL HEAT  

Office of Scientific and Technical Information (OSTI)

67006 67006 INFORMAL REPORT PROPERTIES AND PERFORMANCE OF CEMENT- BASED GROUTS FOR GEOTHERMAL HEAT PUMP APPLICATIONS FINAL REPORT FY 1999 M.L. Allan and A.J. Philippacopoulos November 1999 Prepared for: Office of Geothermal Technologies United States Department of Energy Washington, DC 20585 Materials and Chemical Sciences Division DISCLAIMER This document was prepared as an account of work sponsored by an agenc:y of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees makers any warranty, express or implied, or assumes any legal liability or responsibility of the accuracy, completeness, or usefulness of any information, apparatus, product or process disclosed, or represents that its use

143

Expert Meeting Report: Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems  

Broader source: Energy.gov (indexed) [DOE]

Exploring the Disconnect Exploring the Disconnect Between Rated and Field Performance of Water Heating Systems M. Hoeschele and E. Weitzel Alliance for Residential Building Innovation (ARBI) May 2013 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, subcontractors, or affiliated partners makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark,

144

Film Cooling Performance in a Transonic High-pressure Vane: Decoupled Simulation and Conjugate Heat Transfer Analysis  

Science Journals Connector (OSTI)

Abstract The continuous demand for increased performance and reliability of gas turbines leads to the improvement of prediction tools. Having regard to the effects of heat transfer on the residual life of gas turbine components, it is necessary to achieve a high level of accuracy in the evaluation of thermal loads. Computational fluid dynamics is able to provide reliable data in a limited lapse of time. In this paper, the numerical analysis of the cooled vane of the MT1 high-pressure turbine stage is presented. A grid dependence analysis based on the evaluation of the aero-thermal characteristics of the vane has been performed. Turbulence is modeled using the kT-kL-? method whose performance in this kind of configuration is rarely debated in the scientific literature. Model parameters have been tuned to match the experimental data. The final objective of the present activity is to assess the capability of numerical methods to deal with an annular, transonic high-pressure vane with a realistic film cooling configuration. Adiabatic effectiveness, heat transfer coefficient and net heat flux reduction distributions have been evaluated, the latter providing relevant information on the performance of the cooling system. The coupled fluid-solid simulation of the cooled configuration has also been performed to evaluate the impact of conjugate heat transfer on the prediction of thermal loads. Results show a non-negligible difference in the wall temperature evaluation between the decoupled and the coupled approach, mainly caused by the heat conduction in the solid.

Massimiliano Insinna; Duccio Griffini; Simone Salvadori; Francesco Martelli

2014-01-01T23:59:59.000Z

145

Seasonal Tips | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Seasonal Tips Seasonal Tips Seasonal Tips January 23, 2012 - 11:30am Addthis Amanda McAlpin I've often wished I lived in one of those fabulous places where it's 72 degrees and sunny year-round. But unfortunately, most of us don't. And to stay comfortable, we need heat and hot coffee in the winter, and air-conditioning and lemonade in the summer. Luckily, part of the Energy Savers site is dedicated to helping us save energy during all four seasons. Bring up the dedicated Energy Savers seasonal website and learn great ways to reduce your energy bill. Tips range from small changes you can make immediately, such as closing your drapes, to information on modifications you can make to your home for even larger benefits. There is even information on assistance for energy-savings improvements to your home.

146

Thermal performance of phase change material energy storage floor for active solar water-heating system  

Science Journals Connector (OSTI)

The conventional active solar water-heating floor system contains a big water tank to store energy in the day time for heating at night, which takes much building space and is very heavy. In order to reduce the w...

Ruolang Zeng; Xin Wang; Wei Xiao…

2010-06-01T23:59:59.000Z

147

Toward High Performance Thermoset/Carbon Nanotube Sheet Nanocomposites via Resistive Heating Assisted Infiltration and Cure  

Science Journals Connector (OSTI)

Thermoset/carbon nanotube (CNT) sheet nanocomposites were successfully fabricated by resistive heating assisted infiltration and cure (RHAIC) of the polymer matrix resin. Resistive heating takes advantage of the electrical and thermal conductivity of CNTs ...

Jae-Woo Kim; Godfrey Sauti; Emilie J. Siochi; Joseph G. Smith; Russell A. Wincheski; Roberto J. Cano; John W. Connell; Kristopher E. Wise

2014-10-17T23:59:59.000Z

148

Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Ultra-High Energy Efficient Research Homes  

SciTech Connect (OSTI)

The more widespread use of Ground Source Heat Pump (GSHP) systems has been hindered by their high first cost, which is mainly driven by the cost of the drilling and excavation for installation of ground heat exchangers (GHXs). A new foundation heat exchanger (FHX) technology was proposed to reduce first cost by placing the heat exchanger into the excavations made during the course of construction (e.g., the overcut for the basement and/or foundation and run-outs for water supply and the septic field). Since they reduce or eliminate the need for additional drilling or excavation, foundation heat exchangers have the potential to significantly reduce or eliminate the first cost premium associated with GSHPs. Since December 2009, this FHX technology has been demonstrated in two ultra-high energy efficient new research houses in the Tennessee Valley, and the performance data has been closely monitored as well. This paper introduces the FHX technology with the design, construction and demonstration of the FHX and presents performance monitoring results of the FHX after one year of monitoring. The performance monitoring includes hourly maximum and minimum entering water temperature (EWT) in the FHX compared with the typical design range, temperature difference (i.e., T) across the FHX, and hourly heat transfer rate to/from the surrounding soil.

Im, Piljae [ORNL] [ORNL; Hughes, Patrick [ORNL] [ORNL; Liu, Xiaobing [ORNL] [ORNL

2012-01-01T23:59:59.000Z

149

Analysis of system performance losses due to the reversing valve for a heat pump using R-410a  

SciTech Connect (OSTI)

A traditional reversing valve enables a heat pump to operate in the heating mode or cooling mode by switching the refrigerant flow path through the indoor and outdoor coils, thereby changing the functions of the two heat exchangers. However, the presence of a reversing valve causes additional pressure drops and undesired heat exchange. The objective of this research was to measure the overall effects of a reversing valve on a 3-ton heat pump system using R-401a and make comparisons to the same valve's performance with R-22 as the refrigerant. The experiments included tests of under- and over-sized valves at the same test conditions. Also, the effects of pressure drops and of heat transfer combined with mass leakage on system and compressor performance were analyzed. It was found that the use of a larger (oversized) reversing valve to reduce pressure drops provided only limited performance gains. Also, changing refrigerant from R-22 to R-410a resulted in an increase in mass leakage but did not significantly change the effect that the reversing valve had on the system COP.

Fang, W.; Nutter, D.W.

1999-07-01T23:59:59.000Z

150

Measured Performance and Analysis of Ground Source Heat Pumps for Space Conditioning and for Water Heating in a Low-Energy Test House Operated under Simulated Occupancy Conditions  

SciTech Connect (OSTI)

In this paper we present measured performance and efficiency metrics of Ground Source Heat Pumps (GSHPs) for space conditioning and for water heating connected to a horizontal ground heat exchanger (GHX) loop. The units were installed in a 345m2 (3700ft2) high-efficiency test house built with structural insulated panels (SIPs), operated under simulated occupancy conditions, and located in Oak Ridge, Tennessee (USA) in US Climate Zone 4 . The paper describes distinctive features of the building envelope, ground loop, and equipment, and provides detailed monthly performance of the GSHP system. Space conditioning needs of the house were completely satisfied by a nominal 2-ton (7.0 kW) water-to-air GSHP (WA-GSHP) unit with almost no auxiliary heat usage. Recommendations for further improvement through engineering design changes are identified. The comprehensive set of data and analyses demonstrate the feasibility and practicality of GSHPs in residential applications and their potential to help achieve source energy and greenhouse gas emission reduction targets set under the IECC 2012 Standard.

Ally, Moonis Raza [ORNL] [ORNL; Munk, Jeffrey D [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Gehl, Anthony C [ORNL] [ORNL

2012-01-01T23:59:59.000Z

151

Study of Performance of Heat Pump Usage in Sewage Treatment and Fouling Impact on System  

E-Print Network [OSTI]

A heat pump using disposed sewage as a heat source to heat raw sewage is presented to solve the problem that sewage temperature is low in sewage biologic treatment in cold region. According to the status of one medicine factory in Harbin, China...

Song, Y.; Yao, Y.; Ma, Z.; Na, W.

2006-01-01T23:59:59.000Z

152

Performance and thermo-economic assessments of geothermal district heating system: A case study in Afyon, Turkey  

Science Journals Connector (OSTI)

In this study energy, exergy and exergoeconomic analysis of the Afyon geothermal district heating system (AGDHS) in Afyon, Turkey is performed through thermodynamic performances and thermo-economic assessments. In the analysis, actual system data are used to assess the district heating system performance, energy and exergy efficiencies, exergy losses and loss cost rates. Energy and exergy losses throughout the AGDHS are quantified and illustrated in the flow diagram. The energy and exergy efficiencies of the overall system are found to be 37.59% and 47.54%, respectively. The largest exergy loss occurs in the heat exchangers with 14.59% and then in the reinjection wells with 14.09%. Besides, thermo-economic evaluations of the AGDHS are given in table. Energy and exergy loss rates for the AGDHS are estimated to be 5.36 kW/$ and 0.2  kW/$, respectively.

Ali Keçeba?

2011-01-01T23:59:59.000Z

153

Performance of a solar-ambient hybrid source heat pump drier for copra drying under hot-humid weather conditions  

Science Journals Connector (OSTI)

Abstract This paper communicates the energy performance of a solar-ambient hybrid source heat pump drier (SAHSHPD) for copra drying under hot-humid weather conditions. The standard energy performance parameters such as coefficient of performance (COP), condenser heat capacity (Qc) and specific moisture extraction rate (SMER) were evaluated. The results showed that COP of a SAHSHPD was varied between 2.31 and 2.77 with an average value of 2.54. The condenser heating capacity was varied between 2900 W and 3750 W with an average value of 3290 W. The SMER was calculated as 0.79 kg/kWh. The moisture content (on wet basis) of the copra was reduced from about 52% to about 9.2% and 9.8% in 40 h for trays at bottom and top, respectively. The quality of copra obtained in a SAHSHPD was found to be higher compared to other drying methods.

M. Mohanraj

2014-01-01T23:59:59.000Z

154

Performance of a Heat Pump Water Heater in the Hot-Humid Climate, Windermere, Florida (Fact Sheet)  

SciTech Connect (OSTI)

Over recent years, heat pump water heaters (HPWHs) have become more readily available and more widely adopted in the marketplace. For a 6-month period, the Building America team Consortium for Advanced Residential Buildings monitored the performance of a GE Geospring HPWH in Windermere, Florida. The study found that the HPWH performed 144% more efficiently than a traditional electric resistance water heater, saving approximately 64% on water heating annually. The monitoring showed that the domestic hot water draw was a primary factor affecting the system's operating efficiency.

Metzger, C.; Puttagunta, S.; Williamson, J.

2013-11-01T23:59:59.000Z

155

Nanofluid \\{PCMs\\} for thermal energy storage: Latent heat reduction mechanisms and a numerical study of effective thermal storage performance  

Science Journals Connector (OSTI)

Abstract The latent heat of fusion of paraffin-based nanofluids has been examined to investigate the use of enhanced phase change materials (PCMs) for thermal energy storage (TES) applications. The nanofluid approach has often been exploited to enhance thermal conductivity of PCMs, but the effects of particle addition on other thermal properties affecting TES are relatively ignored. An experimental study of paraffin-based nanofluids containing various particle sizes of multi-walled carbon nanotubes has been conducted to investigate the effect of nanoparticles on latent heat of fusion. Results demonstrated that the magnitude of nanofluid latent heat reduction increases for smaller diameter particles in suspension. Three possible mechanisms – interfacial liquid layering, Brownian motion, and particle clustering – were examined to explain further reduction in latent heat, through the weakening of molecular bond structures. Although additional research is required to explore detailed mechanisms, experimental evidence suggests that interfacial liquid layering and Brownian motion cannot explain the degree of latent heat reduction observed. A finite element model is also presented as a method of quantifying nanofluid PCM energy storage performance. Thermal properties based on modified effective medium theory and an empirical relation for latent heat of fusion were applied as model parameters to determine energy stored and extracted over a given period of time. The model results show that while micro-scale particle inclusions exhibit some performance enhancement, nanoparticles in \\{PCMs\\} provide no significant improvement in TES performance. With smaller particles, the enhancement in thermal conductivity is not significant enough to overcome the reduction in latent heat of fusion, and less energy is stored over the PCM charge period. Therefore, the nanofluid approach may not be justifiable for energy storage applications. However, since the model parameters are dependent on the material properties of the system observed, storage performance may vary for differing nanofluid materials.

Aitor Zabalegui; Dhananjay Lokapur; Hohyun Lee

2014-01-01T23:59:59.000Z

156

Domestic Heating and Thermal Insulation  

Science Journals Connector (OSTI)

... DIGEST 133 of the Building Research Station, entitled "Domestic Heating and Thermal Insulation" (Pp. 7. London : H.M. Stationery Office, 1960. 4insulation, the standard of heating, the ventilation-rate and the length of the heating season ...

1960-09-17T23:59:59.000Z

157

Advanced Heat Transfer Technologies Increase Vehicle Performance and Reliability, The Spectrum of Clean Energy Innovation (Fact Sheet)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Advanced Heat Transfer Advanced Heat Transfer Technologies Increase Vehicle Performance and Reliability Keeping yourself cool while driving your car on a hot, sunny day can be a challenge. But it can be even more challenging to cool the power electronic components that are critically important in hybrid electric and all-electric vehicles. Researchers at the National Renewable Energy Laboratory (NREL) investigate and develop these vehicles and their components to help reduce our use of imported petroleum and curb the emissions associated with climate change. A vehicle's power electronic components include the motor controller, converters, and inverters that condition the flow of electrical power between the battery and the electric motor. The problem is that power electronics generate a lot of heat. This heat can decrease

158

Effects of different operating conditions of Gonen geothermal district heating system on its annual performance  

Science Journals Connector (OSTI)

Abstract In this paper, the effects of different operating conditions of the Gonen geothermal district heating system (GDHS) on its annual energy and exergy performance are investigated. The system parameters such as temperature, pressure and flow rate are monitored by using fixed and portable measuring instruments over a one-year period. Thus the main differences in the annual system operation are detected. The measurements show that the Gonen GDHS has six different operating cases depending on the outside temperature throughout the year. The energy and exergy analysis of the system is carried out for each case using the actual system parameters at the corresponding reference temperatures, which are 3.86, 7.1, 8.88, 11.83, 15.26 and 20.4 °C. The highest and lowest energy (57.32%, 35.64%) and exergy (55.76%, 41.42%) efficiencies of the overall system are calculated at the reference temperatures of 15.26 °C and 3.86 °C, respectively. Besides, taking the six case-based energy and exergy analyses into account, the annual average energy and exergy efficiencies are determined to be 45.24% and 47.33%, respectively.

Asiye Aslan; Bedri Yüksel; Tu?rul Akyol

2014-01-01T23:59:59.000Z

159

Comparison of U-tube boreholes and a thermosiphon on heat pump performance in an aquifer.  

E-Print Network [OSTI]

??Reducing our energy consumption and dependence on fossil fuels has become a common social, political and engineering goal. Heating and cooling of buildings account for… (more)

Workman, Christopher B.

2011-01-01T23:59:59.000Z

160

Improving Process Heating System Performance: A Sourcebook for Industry, Second Edition  

SciTech Connect (OSTI)

This is one in a series of sourcebooks to help manufacturers optimize their industrial systems; this particular sourcebook addresses process heating systems.

Not Available

2008-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Improving the Performance of Heat Insulation Polyurethane Foams by Silica Nanoparticles  

Science Journals Connector (OSTI)

Heat insulation polyurethane foam materials were doped by silica nano particles, ... , thermal and mechanical properties of polyurethane rigid foam were investigated. Thermal and mechanical properties were...

M. M. Alavi Nikje; A. Bagheri Garmarudi; M. Haghshenas…

2009-01-01T23:59:59.000Z

162

Waste Heat Reduction and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A BestPractices Process Heating Technical Brief  

SciTech Connect (OSTI)

This technical brief is a guide to help plant operators reduce waste heat losses associated with process heating equipment.

Not Available

2004-11-01T23:59:59.000Z

163

Waste Heat Reduction and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A BestPractices Process Heating Technical Brief  

Broader source: Energy.gov [DOE]

This technical brief is a guide to help plant operators reduce waste heat losses associated with process heating equipment.

164

Improving the Control Performance of an Organic Rankine Cycle System for Waste Heat Recovery from a Heavy-Duty  

E-Print Network [OSTI]

Improving the Control Performance of an Organic Rankine Cycle System for Waste Heat Recovery from and efficiency of those systems. The system considered here is an Organic Rankine Cycle (ORC) for recovering internal combustion engines presented in [1]. The system considered here is an Organic Rankine Cycle (ORC

Paris-Sud XI, Université de

165

Performance Analysis of a Thermoelectric Solar Collector Integrated with a Heat Pump  

Science Journals Connector (OSTI)

A novel heat pump system is proposed. A thermoelectric solar collector was coupled to a solar-assisted heat pump (TESC-HP) to work as an ... ambient temperature of 32.5°C and average solar intensity of 815 W/m2, ...

C. Lertsatitthanakorn; J. Jamradloedluk; M. Rungsiyopas…

2013-07-01T23:59:59.000Z

166

A DISCUSSION OF HEAT MIRROR FILM: PERFORMANCE, PRODUCTION PROCESS, AND COST ESTIMATES  

E-Print Network [OSTI]

transfer thnough a window by using Intrex film as a heatwindow construction will be PROCESS DESCRIPTION Intrex filmWindows and Lighting Program Building 90, Room 2056 Lawrence Berkeley Laboratory Berkeley, California -ii- A DISCUSSION OF HEAT MIRROR FILM:

Levin, B. P.

2011-01-01T23:59:59.000Z

167

Field Performance of a Ground-Coupled Heat Pump in Abilene, Texas  

E-Print Network [OSTI]

U-tube groundcoupled heat pump was installed in guest officer's quarters of Dyess Air Force Base in Abilene, Texas in December 1989. Monitored variables included: water temperature entering and leaving the condenser, temperature and relative...

Dobson, M.; O'Neal, D. L.; Aldred, W.; Margo, R.

1994-01-01T23:59:59.000Z

168

Performance Study of Thermoelectric Solar-Assisted Heat Pump with Reflectors  

Science Journals Connector (OSTI)

The simultaneous conversion of solar radiation into thermal and electrical energy in a thermoelectric (TE) solar-assisted heat pump is, for the purposes of ... plate reflectors have been mounted on a TE solar col...

C. Lertsatitthanakorn; S. Soponronnarit…

2014-06-01T23:59:59.000Z

169

Performance of Solar Assisted Heat Pump Using Pv Evaporator Under ` Different Compressor Frequency  

Science Journals Connector (OSTI)

A novel photovoltaic solar assisted heat pump (PV-SAHP) system was ... -collector plate. So a portion of the solar energy received was converted to electricity and ... pump was also substantially improved because...

Gang Pei; Jie Ji; Chongwei Han; Wen Fan

2009-01-01T23:59:59.000Z

170

Thermodynamic performance analysis of a combined power cycle using low grade heat source and LNG cold energy  

Science Journals Connector (OSTI)

Abstract Thermodynamic analysis of a combined cycle using a low grade heat source and LNG cold energy was carried out. The combined cycle consisted of an ammonia–water Rankine cycle with and without regeneration and a LNG Rankine cycle. A parametric study was conducted to examine the effects of the key parameters, such as ammonia mass fraction, turbine inlet pressure, condensation temperature. The effects of the ammonia mass fraction on the temperature distributions of the hot and cold streams in heat exchangers were also investigated. The characteristic diagram of the exergy efficiency and heat transfer capability was proposed to consider the system performance and expenditure of the heat exchangers simultaneously. The simulation showed that the system performance is influenced significantly by the parameters with the ammonia mass fraction having largest effect. The net work output of the ammonia–water cycle may have a peak value or increase monotonically with increasing ammonia mass fraction, which depends on turbine inlet pressure or condensation temperature. The exergy efficiency may decrease or increase or have a peak value with turbine inlet pressure depending on the ammonia mass fraction.

Kyoung Hoon Kim; Kyung Chun Kim

2014-01-01T23:59:59.000Z

171

Performance Analysis of Exhaust Waste Heat Recovery System for Stationary CNG Engine Based on Organic Rankine Cycle  

Science Journals Connector (OSTI)

Abstract In order to improve the electric efficiency of a stationary compressed natural gas (CNG) engine, a set of organic Rankine cycle (ORC) system with internal heat exchanger (IHE) is designed to recover exhaust energy that is used to generate electricity. R416A is selected as the working fluid for the waste heat recovery system. According to the first and second laws of thermodynamics, the performances of the ORC system for waste heat recovery are discussed based on the analysis of engine exhaust waste heat characteristics. Subsequently, the stationary CNG engine-ORC with IHE combined system is presented. The electric efficiency and the brake specific fuel consumption (BSFC) are introduced to evaluate the operating performances of the combined system. The results show that, when the evaporation pressure is 3.5MPa and the engine is operating at the rated condition, the net power output and the thermal efficiency of the ORC system with IHE can reach up to 62.7kW and 12.5%, respectively. Compared with the stationary CNG engine, the electric efficiency of the combined system can be increased by a maximum 6.0%, while the BSFC can be reduced by a maximum 5.0%.

Songsong Song; Hongguang Zhang; Zongyong. Lou; Fubin Yang; Kai Yang; Hongjin Wang; Chen Bei; Ying Chang; Baofeng Yao

2014-01-01T23:59:59.000Z

172

Divertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus Experiment.  

SciTech Connect (OSTI)

Experiments conducted in high-performance 1.0-1.2 MA 6 MW NBI-heated H-mode plasmas with a high flux expansion radiative divertor in NSTX demonstrate that significant divertor peak heat flux reduction and access to detachment may be facilitated naturally in a highly-shaped spherical torus (ST) configuration. Improved plasma performance with high {beta}{sub p} = 15-25%, a high bootstrap current fraction f{sub BS} = 45-50%, longer plasma pulses, and an H-mode regime with smaller ELMs has been achieved in the lower single null configuration with higher-end elongation 2.2-2.4 and triangularity 0.6-0.8. Divertor peak heat fluxes were reduced from 6-12 MW/m{sup 2} to 0.5-2 MW/m{sup 2} in ELMy H-mode discharges using high magnetic flux expansion and partial detachment of the outer strike point at several D{sub 2} injection rates, while good core confinement and pedestal characteristics were maintained. The partially detached divertor regime was characterized by a 30-60% increase in divertor plasma radiation, a peak heat flux reduction by up to 70%, measured in a 10 cm radial zone, a five-fold increase in divertor neutral pressure, and a significant volume recombination rate increase.

Soukhanovskii, V A; Maingi, R; Gates, D; Menard, J; Paul, S F; Raman, R; Roquemore, A L; Bell, R E; Bush, C; Kaita, R

2008-09-22T23:59:59.000Z

173

Development of an integrated building load and ground source heat pump model to assess heat pump and ground loop design and performance in a commercial office building.  

E-Print Network [OSTI]

??Ground source heat pumps (GSHPs) offer an efficient method for cooling and heating buildings, reducing energy usage and operating cost. In hot, arid regions such… (more)

Blair, Jacob Dale

2014-01-01T23:59:59.000Z

174

Comparison of ICRF and NBI heated plasmas performances in the JET ITER-like wall  

SciTech Connect (OSTI)

During the initial operation of the JET ITER-like wall, particular attention was given to the characterization of the Ion Cyclotron Resonance Frequency (ICRF) heating in this new metallic environment. In this contribution we compare L-modes plasmas heated by ICRF or by Neutral Beam Injection (NBI). ICRF heating as expected led to a much higher centrally peaked power deposition on the electrons and due to the central fast ion population to stronger sawtooth activity. Surprisingly, although a higher bulk radiation was observed during the ICRF phase, the thermal plasma energy was found similar for both cases, showing that a higher radiation inside the separatrix was not incompatible with an efficient central heating scheme. The higher radiation was attributed to the presence Tungsten (W). Tomographic inversion of SXR emissions allowed a precise observation of the sawtooth effect on the radiation pattern. W concentration profiles deconvolved from SXR emission showed the flattening of the profiles due to sawtooth for both heating and the peaking of the profiles in the NBI case only hinting for extra transport effect in the ICRF case.

Mayoral, M.-L. [EFDA Close Support Unit, Garching, Germany and Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Pütterich, T.; Bobkov, V. [Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Jacquet, P. [Euratom/CCFE Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Lerche, E.; Van-Eester, D.; Bourdelle, C.; Colas, L. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Czarnecka, A. [Association Euratom-IPPLM, Hery 23, 01-497 Warsaw (Poland); Mlynar, J. [Association Euratom-IPP.CR, Institute of Plasma Physics AS CR, 18200 Prague (Czech Republic); Neu, R. [EFDA Close Support Unit, Garching, Germany and Max-Planck-Institut für Plasmaphysik, EURATOM-Assoziation, Garching (Germany); Collaboration: JET-EFDA Contributors

2014-02-12T23:59:59.000Z

175

Simulation of heat pipe rapid transient performance using a multi-nodal implicit finite difference scheme  

E-Print Network [OSTI]

capillary pumping head is given by 2 0' Ap C XXX z erst where 6 = the surface tension of the working fluid r?rc = the minimum radius of curvature and is given for wire meshes as w+d r CIlt where w = width of pore d = wire diameter. The maximum... Difference Scheme James Samuel Peery, B. S. , Texas A&M University Chairman of Advisory Committee: Dr. Frederick R. Best A multi ? nodal, implicit, finite difference model, Heat Pipe Transient Analysis Code (HPTAC), has been developed to simulate heat...

Peery, James Samuel

2012-06-07T23:59:59.000Z

176

Experimental study of an air-source heat pump for simultaneous heating and cooling Part 1: Basic concepts and performance verification  

E-Print Network [OSTI]

manufacturer. The operation of the high pressure control system, the transitions between heating, cooling, heating and cooling energies using the same electric energy input at the compressor. Chua et al. [31 Experimental study of an air-source heat pump for simultaneous heating and cooling ­ Part 1

Boyer, Edmond

177

Numerical Simulation of Thermal Performance of Floor Radiant Heating System with Enclosed Phase Change Material  

E-Print Network [OSTI]

of the energy storage floor is designed,which places heat pipes in the enclosed phase change material (PCM) layer, without concrete in it. The PCM thermal storage time is studied in relation to the floor surface temperature under different low-temperature hot...

Qiu, L.; Wu, X.

2006-01-01T23:59:59.000Z

178

Performance investigation of thermal energy storage system with Phase Change Material (PCM) for solar water heating application  

Science Journals Connector (OSTI)

Abstract In order to harvest solar energy, thermal energy storage (TES) system with Phase Change Material (PCM) has been receiving greater attention because of its large energy storage capacity and isothermal behavior during charging and discharging processes. In the present experimental study, shell and tube TES system using paraffin wax was used in a water heating system to analyze its performance for solar water heating application. Energy and exergy including their cost analyses for the TES system were performed. Accordingly, total life cycle cost was calculated for different flow rates of the Heat Transfer Fluid (HTF). With 0.033 kg/min and 0.167 kg/min flow rates of water as HTF, energy efficiencies experienced were 63.88% and 77.41%, respectively, but in exergy analysis, efficiencies were observed to be about 9.58% and 6.02%, respectively. Besides, the total life cycle cost was predicted to be $ 654.61 for 0.033 kg/min flow rate, which could be reduced to $ 609.22 by increasing the flow rate to 0.167 kg/min. Therefore it can be summarized that total life cycle cost decreases with the increase of flow rate.

M.H. Mahfuz; M.R. Anisur; M.A. Kibria; R. Saidur; I.H.S.C. Metselaar

2014-01-01T23:59:59.000Z

179

Remediation of asbestos containing materials by Joule heating vitrification performed in a pre-pilot apparatus  

Science Journals Connector (OSTI)

A remediation method for asbestos containing materials based on vitrification by Joule heating is presented. Crystal phase transformations of several asbestos minerals were investigated. The vitrification technology on a pre-pilot scale was applied to cement-asbestos pipes containing simultaneously chrysotile and crocidolite. The progressive heating up to 1600 °C led to the complete melting of fibrous minerals and the rapid cooling of the melt formed a monolithic glass. Mineralogical (XRD) and morphological (SEM) analysis showed absence of crystalline phases within the glass. The external part of the Joule heated volume was not melted but lacked asbestos because of an irreversible thermal conversion of asbestos and silicate minerals into high temperature silicates (enstatite and diopside). An absolute filter integrated in the gas effluent treatment system avoided the release of asbestos fibres during the vitrification process. This process assured the complete remediation of asbestos containing materials and its scaling up to the field application could be a suitable industrial treatment of tons of material.

Francesco Dellisanti; Piermaria L. Rossi; Giovanni Valdrè

2009-01-01T23:59:59.000Z

180

Solar Heating with Annual Heat Storage — Modelling and Practice  

Science Journals Connector (OSTI)

Central solar heating systems with seasonal heat storage are recognized as one of the most potential forms of solar energy utilization at northern latitudes. Because of ... and energy flows of a full-scale distri...

P. D. Lund; S. S. Peltola

1984-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Topic 14. Retrofit and optimal operation of the building energy systems Performances of Low Temperature Radiant Heating Systems  

E-Print Network [OSTI]

panel system are given by its energy (the consumption of gas for heating, electricity for pumps Temperature Radiant Heating Systems Milorad Boji1*, Dragan Cvetkovi1 , Jasmina Skerli1 , Danijela Nikoli1, wall heating, floor heating, ceiling heating, EnergyPlus SUMMARY Low temperature heating panel systems

Paris-Sud XI, Université de

182

Improving central heating plant performance at the defense construction supply center (DCSC): Advanced operation and maintenance methods. Final report  

SciTech Connect (OSTI)

A 1987 air pollution emissions test done by the U.S. Army Environmental Hygiene Agency (USAEHA) identified several problems with the central heating plant (CHP) at the Defense Construction Supply Center (DCSC), Columbus, OH. Though DCSC repaired the specified problems, improved coal specifications, and tried to reduce air infiltration, CHP performance remained at unacceptable levels. Consequently, DCSC contracted the U.S. Army Construction Engineering Research Laboratories (USACERL) to apply advanced operation and maintenance procedures to improve its combustion system. This study employed a system-wide approach to evaluate the CHP 5 fuel storage, combustion, heat distribution, and the control of air emissions. Many short-term improvements to the CHP were identified and tested. Subsequent combustion and air emissions tests revealed that the recommended improvements successfully increased CHP efficiency. Long-term improvements were also recommended to help maintain the short-term improvements.

Savoie, M.J.; Standerfer, J.; Schmidt, C.M.; Gostich, J.; Mignacca, J.

1994-11-01T23:59:59.000Z

183

The development of a kinematic Stirling-engine-driven heat pump  

SciTech Connect (OSTI)

The continuing development of a 10-ton light commercial natural-gas-fired kinematic Stirling-engine-driven heat pump system is described. Basic Stirling cycle thermodynamics are presented, and a complete engine heat balance is shown to detail the inherent advantages of the V160 Stirling engine as a prime mover in a heat pump package. Results from environmental laboratory testing of a breadboard prototype are reviewed, and the test procedures used in the evaluation are explained. Seasonal performance of the heat pump package was predicted using a bin-temperature method based on Chicago and Dallas climatic data. Annual energy costs, as predicted by the seasonal performance analytical computer program, have been calculated for a gas furnace, standard electric heat pump, and the Stirling engine-driven prototype heat pump package. These computed costs for these systems are listed and compared.

Monahan, R.E.; Kountz, K.J.; Clinch, J.M.

1987-06-01T23:59:59.000Z

184

Sludge, fuel degradation and reducing fouling on heat exchangers  

SciTech Connect (OSTI)

Brookhaven National Laboratory, under contract to the US Department of Energy, operates an oil heat research primarily to lower energy consumption in the 12 million oil heated homes in the US. The program objectives include: Improve steady state efficiency of oil heating equipment, Improve seasonal efficiencies, Eliminate or minimize factors which tend to degrade system performance. This paper provides an overview of the status of three specific projects which fall under the above objectives. This includes our fuel quality project, oil appliance venting and a project addressing efficiency degradation due to soot fouling of heat exchangers.

Butcher, T.; Litzke, Wai Lin; Krajewski, R.; Celebi, Y.

1992-02-01T23:59:59.000Z

185

Thermal hydraulic performance testing of printed circuit heat exchangers in a high-temperature helium test facility  

SciTech Connect (OSTI)

In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750–800 °C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot and 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 °C/1.0–2.7 MPa for the cold side and 208–790 °C/1.0–2.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.

Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup; Richard N. Christensen; Michael W. Patterson

2014-04-01T23:59:59.000Z

186

Experimental study on the performance of solar-assisted multi-functional heat pump based on enthalpy difference lab with solar simulator  

Science Journals Connector (OSTI)

Abstract In the enthalpy difference lab with a solar simulator, the performance of the indirect expansion solar-assisted multi-functional heat pump (IX-SAMHP) can be tested in stable external environment quantificationally. In this paper, the performances of the IX-SAMHP working in the solar water heating mode and solar space heating mode were compared under different conditions. The experimental results indicate that the evaporating heat exchange rate and condensing heat exchange rate were synthetically effected by the evaporating and condensing temperature in the solar water heating mode. Moreover, compared with the situation without irradiation, when the irradiation was 500 W/m2, the evaporating heat exchange rate and condensing heat exchange rate increased by 37.4% and 32.3%, respectively. In the solar space heating mode, when the irradiation increased from 0 W/m2 to 500 W/m2, the heating capacity increased by 20.4%. In the second-law analysis, the calculating results demonstrate that the exergy efficiency of the IX-SAMHP would be enhanced by inputting solar energy to the evaporator.

Ji Jie; Cai Jingyong; Huang Wenzhu; Feng Yan

2015-01-01T23:59:59.000Z

187

Influences of ambient air speed and internal heat load on the performance of solar chimney in the tropics  

Science Journals Connector (OSTI)

Abstract Solar chimney is a combination of solar assisted stack and wind driven ventilation where air in the solar chimney expands under heating from solar irradiance and being relatively lighter, rises out from the chimney outlets, drawing the cooler air into the building through the fenestrations. This pull effect is complemented further by the push effect from the outdoor ambient wind. The study of solar chimney system within the zero energy building in tropical Singapore aims to determine the effects of ambient air speed and internal heat load on the thermal environment of the solar chimney ducts and classroom’s interior. Experimental and computational results show that high ambient air speed greater than 2.00 m/s improves the air speed within the solar chimney ducts; both low and high ambient air speeds are found to improve the classroom’s interior air speed. However, the significance of ambient air speed drops when solar irradiance is greater than 700 W/m2. Furthermore, under the tropical weather conditions of high solar irradiance and low ambient air speed, cross ventilation performs better compared to solar chimney; hence, solar chimney is recommended to be employed under zero ambient air speed. Lastly, results show that the influences of internal heat load on the air temperature and speed within solar chimney ducts as well as classroom’s interior are limited.

Alex Yong Kwang Tan; Nyuk Hien Wong

2014-01-01T23:59:59.000Z

188

System Modeling and Building Energy Simulations of Gas Engine Driven Heat Pump  

SciTech Connect (OSTI)

To improve the system performance of a gas engine driven heat pump (GHP) system, an analytical 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 with a detailed vapor compression heat pump system design model. 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 the desiccant system the sensible heat ratio (SHR- sensible heat ratio) can be lowered to 40%. The waste heat of the gas engine can boost the space heating efficiency by 25% at rated operating conditions. In addtion,using EnergyPlus, building energy simulations have been conducted to assess annual energy consumptions of GHP in sixteen US cities, and the performances are compared to a baseline unit, which has a electrically-driven air conditioner with the seasonal COP of 4.1 for space cooling and a gas funace with 90% fuel efficiency for space heating.

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

2013-01-01T23:59:59.000Z

189

Engineering Aspects of Heat Transfer in Multilayer Reflective Insulation and Performance of NRC Insulation  

Science Journals Connector (OSTI)

All types of high-performance insulation, often referred to as “superinsulation,” ... Carbide Corporation in October, 1958, or the insulation proposed and tested in 1951 by P. ... D. Little, Inc., or the NRC insulation

M. P. Hnilicka

1960-01-01T23:59:59.000Z

190

Evaluation on Energy Performance of Heating Plant System Installed Energy Saving Technologies  

E-Print Network [OSTI]

of Cooling Water in Production Area: 3.5MW (11942KBtu/h), 1unit Heat Discharge: 2.6MW (8872KBtu/h), 1unit Additional Operation with Screw Refrigeration Machine: 2.3MW (7847KBtu/h), 1unit Turbo Refrigerating Machine (1.41MW): 152m3/h (5398mf3/h), 2units... Production Area (North) Production Area (South) Water Treatment Plant 21Cells Unit (14.1MW) Turbo Refrigerating Machines (1.4MW, 2units/ 4.2MW,6units) Screw Refrigerating Machines (0.8MW, 2units) Iced-thermal Storage Tank (28.5GJ, 2units) HEX for Additional...

Song, Y.; Akashi, Y.; Kuwahara, Y.; Baba, Y.; Iribe, M.

2004-01-01T23:59:59.000Z

191

Are window energy performance selection requirements in line with product design in heating-dominated climates?  

SciTech Connect (OSTI)

This paper discusses energy efficiency criteria for selecting windows and the limitations imposed by the necessity of a factory rating number as opposed to using specific design criteria for each house window. The Canadian annual energy rating (ER) system for residential windows that was derived for use in a cold climate where passive solar gains are significant is described. Corrections are noted to account for specific house differences and for cooling situations. The conclusion is that a rating system must account accurately for solar gain since passive solar is important in this climate. Adoption of the rating system has led to improvements in window design and fabrication beyond simply incorporating low-e glass and argon in sealed double units. Examples are given to illustrate substantially higher ER numbers obtained through improvements that impact on both overall U-factor and solar heat gain coefficient (SHGC).

Henry, R.; Dubrous, F. [Natural Resources Canada, Ottawa, Ontario (Canada)

1998-12-31T23:59:59.000Z

192

An experimental study on the effect of ultrasonication on viscosity and heat transfer performance of aqueous suspensions of multi-walled carbon nanotubes  

E-Print Network [OSTI]

Through past research, it is known that carbon nanotubes have the potential of enhancing the thermal performance of heat transfer fluids. The research is of importance in electronics cooling, defense, space, transportation applications and any other...

Garg, Paritosh

2009-05-15T23:59:59.000Z

193

Measured Effects of Retrofits - A Refrigerant Oil Additive and a Condenser Spray Device - On the Cooling Performance of a Heat Pump  

E-Print Network [OSTI]

A 15-year old, 3-ton single package air-to-air heat pump was tested in laboratory environmental chambers simulating indoor and outdoor conditions. After documenting initial performance, the unit was retrofitted with a prototype condenser water...

Levins, W. P.; Sand, J. R.; Baxter, V. D.; Linkous, R. S.

1996-01-01T23:59:59.000Z

194

Building America Technology Solutions for New and Existing Homes: Performance of a Heat Pump Water Heater in the Hot-Humid Climate, Windermere, Florida (Fact Sheet)  

Broader source: Energy.gov [DOE]

For a 6-month period, the Building America team Consortium for Advanced Residential Buildings monitored the performance of a heat pump water heater in Windermere, Florida. The study found that the HPWH performed 144% more efficiently than a traditional electric resistance water heater, saving approximately 64% on water heating annually. The monitoring showed that the domestic hot water draw was a primary factor affecting the system's operating efficiency.

195

Performance evaluation of the site built trickle solar collector system to heat swimming pool  

SciTech Connect (OSTI)

This report discusses the analysis and field experiment conducted to determine the thermal performance of a particular trickle water collector design. Specific areas examined include the effect of the aspect ratio, flow rate and tilt angle on the collector performance. The exact solar radiation on the sinusoidal absorber plate has to be theoretically calculated. The influence of various design parameters such as corrugation height and width, distance between cover and absorber, tilt angle, and flow rate on the performance is rather small. For a small temperature increase between fluid inlet and outlet the agreement between experimental and theoretical results appears to be reasonable. However, for the higher fluid inlet temperature, and for larger temperature increase, the actual collector efficiency deviates significantly to indicate the necessity of a correction factor such as fogging on the cover plate to the theoretical consideration.

Lee, J.H.; Park, W.H.; Park, K.S.

1985-01-01T23:59:59.000Z

196

Towards a better comprehension of plasma formation and heating in high performances electron cyclotron resonance ion sources (invited)  

SciTech Connect (OSTI)

Further improvements of electron cyclotron resonance ion sources (ECRIS) output currents and average charge state require a deep understanding of electron and ion dynamics in the plasma. This paper will discuss the most recent advances about modeling of non-classical evidences like the sensitivity of electron energy distribution function to the magnetic field detuning, the influence of plasma turbulences on electron heating and ion confinement, the coupling between electron and ion dynamics. All these issues have in common the non-homogeneous distribution of the plasma inside the source: the abrupt density drop at the resonance layer regulates the heating regimes (from collective to turbulent), the beam formation mechanism and emittance. Possible means to boost the performances of future ECRIS will be proposed. In particular, the use of Bernstein waves, in preliminary experiments performed at Laboratori Nazionali del Sud (LNS) on MDIS (microwave discharge ion sources)-type sources, has permitted to sustain largely overdense plasmas enhancing the warm electron temperature, which will make possible in principle the construction of sources for high intensity multicharged ions beams with simplified magnetic structures.

Mascali, D.; Gammino, S.; Celona, L.; Ciavola, G. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania (Italy)

2012-02-15T23:59:59.000Z

197

Equilibrium Model and Performances of an Isopropanol–Acetone–Hydrogen Chemical Heat Pump with a Reactive Distillation Column  

Science Journals Connector (OSTI)

The acetone and hydrogen are then fed into the exothermic reactor after being heated up to the temperature TH in the heater. ... Ajah, A. N.; Mesbah, A.; Grievink, J.; Herder, P. M.; Falcao, P. W.; Wennekes, S.On the robustness, effectiveness and reliability of chemical and mechanical heat pumps for low-temperature heat source district heating: A comparative simulation-based analysis and evaluation Energy 2008, 33, 908– 929 ... heat pump is best suited for high energy demand space heating. ...

Min Xu; Fang Xin; Xunfeng Li; Xiulan Huai; Jiangfeng Guo; Hui Liu

2013-02-25T23:59:59.000Z

198

Parametric performance studies on fluidized-bed heat exchangers. Task I. Fouling characteristics. Yearly technical progress report, 28 July 1981-31 July 1982  

SciTech Connect (OSTI)

Analyses and experiments are being performed in this program to investigate the heat transfer performance of single and multi-stage shallow fluidized beds for application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. The work, which is an extension of that done previously under contracts EC-77-C-03-1433 and DE-AC03-79-ET11348, consists of three tasks. In Task 1, tests have been conducted to investigate the effects of liquid condensate fouling on fluidized bed heat exchanger performance. Liquid condensates used in these tests were water and glycerol (which is more viscous than water). The tests showed that fluidized bed heat exchanger performance is degraded by condensation within the bed and the degradation is caused by bed particles adhering to the heat exchanger surface, not by particle agglomeration. Liquid condensate did not continuously build up within the bed. After a period of dry-out, heat transfer equal to that obtained prior to condensation was again obtained. 8 figures, 1 table.

None

1982-09-01T23:59:59.000Z

199

Spectral effects on the transmittance, solar heat gain, and performance rating of glazing systems  

Science Journals Connector (OSTI)

This study investigates the potential changes in Solar Heat Gain Coefficient (SHGC) and Visible Transmittance (VT) ratings of vertical or tilted glazing systems that would result from a deliberate change in the reference spectrum used as Spectral Weighting Function (SWF). This SWF is necessary to evaluate broadband-average optical properties from their spectral values, and obtain the desired rating of such bulk properties. The \\{SWFs\\} currently specified by rating institutions in Europe and North America for SHGC and VT are now outdated, and their inadequacies are discussed. Six potential replacements, which have been recently adopted by ASTM are described, including three direct irradiance spectra and three global irradiance spectrum incident on tilted surfaces of various tilts (20°, 37° and 90°). Some of these spectra have been tailored for use in building energy applications, including Building-Integrated Photovoltaics (BIPV). The effect of tilt on the U-factor and hence SHGC of glazing systems used for skylights on roofs is discussed, using a representative dataset of 37 glazing system specimens. The spectral effects on SHGC induced by a change in the current North American SWF are also obtained for this dataset, and show small to moderate deviations from current ratings (?2% to +7% for windows, and ?3% to +11% for skylights). The variations in VT are within ±2% for most glazing systems. To remove the current inconsistency in the \\{SWFs\\} used for SHGC and VT, it is recommended that a single SWF be used for both properties. For improved accuracy and reliance on active standards, it is also recommended that the SWF for SHGC and VT be either one of the two recent ASTM G197-08 global irradiance spectra, depending on application (incidence on a vertical surface for window applications, and incidence on a 20°-tilted surface for skylight applications). No change in colorimetric calculations (based on the D65 illuminant) is recommended, however.

Christian A. Gueymard; William C. duPont

2009-01-01T23:59:59.000Z

200

Exergy analysis of two geothermal district heating systems for building applications  

Science Journals Connector (OSTI)

This study evaluates the exergetic performance of two local Turkish geothermal district heating systems through exergy analysis. The exergy destructions in these geothermal district heating systems are quantified and illustrated using exergy flow diagrams for a reference temperature of 1 °C using the 2003 and 2004 actual seasonal heating data. The results indicate that the exergy destructions in these systems particularly occur due to losses in pump, heat exchangers, pipelines, and the reinjection of thermal water. Exergy efficiencies of the two systems are investigated for the system performance analysis and improvement and are determined to be 42.89% and 59.58%, respectively.

Leyla Ozgener; Arif Hepbasli; Ibrahim Dincer

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Water and Space Heating Heat Pumps  

E-Print Network [OSTI]

This paper discusses the design and operation of the Trane Weathertron III Heat Pump Water Heating System and includes a comparison of features and performance to other domestic water heating systems. Domestic water is generally provided through...

Kessler, A. F.

1985-01-01T23:59:59.000Z

202

Regimes of the North Australian Wet Season  

Science Journals Connector (OSTI)

The variability of the north Australian wet season is examined by performing cluster analysis on the wind and thermodynamic information contained in the 2300 UTC radiosonde data at Darwin for 49 wet seasons (September–April) from 1957/58 to 2005/...

Mick Pope; Christian Jakob; Michael J. Reeder

2009-12-01T23:59:59.000Z

203

Residential Heating Oil Prices  

Gasoline and Diesel Fuel Update (EIA)

This chart highlights residential heating oil prices for the current and This chart highlights residential heating oil prices for the current and past heating season. As you can see, prices have started the heating season, about 40 to 50 cents per gallon higher than last year at this time. The data presented are from EIA's State Heating Oil and Propane Program. We normally collect and publish this data twice a month, but given the low stocks and high prices, we started tracking the prices weekly. These data will also be used to determine the price trigger mechanism for the Northeast Heating Oil Reserve. The data are published at a State and regional level on our web site. The slide is to give you some perspective of what is happening in these markets, since you probably will get a number of calls from local residents about their heating fuels bills

204

Comparison of the Thermal Performance of a Solar Heating System with Open and Closed Solid Sorption Storage  

Science Journals Connector (OSTI)

Abstract The aim of this paper is to compare two solar heating systems with different solid sorption storage concepts; an open storage concept with material transport and external reactor and a closed sorption storage concept with the material reservoir as reactor. Both storage concepts are part of system concepts that have been investigated during national projects for a period of more than 3 years each. A TRNSYS model has been developed for each concept and the corresponding mathematical model is described. An emphasis is given on the model simplifications and thus its up- and downscaling possibilities. TRNSYS simulation studies were performed using similar boundary conditions. Hence the simulation results can be compared directly, thus the advantages and disadvantages of both concepts under investigation can be elaborated and assessed. TRNSYS simulations have been performed for each system concept using the properties of two different thermochemical storage materials (TCM). It is shown that the type of TCM has a significant influence on the systems fractional thermal energy savings. Using silica gel as TCM, both system concepts’ performances are only slightly better compared to a standard water-filled storage tank of the same size. The TCM zeolite 13 XBF, a binder free 13 X zeolite, leads to significantly better fractional thermal energy savings. Although the two systems under investigation behave differently, the fractional thermal energy savings are similar. High solar thermal fractions up to a complete solar coverage can be achieved for both storage concepts with moderate collector array and store sizes.

Florian Bertsch; Dagmar Jaehnig; Sebastian Asenbeck; Henner Kerskes; Harald Drueck; Waldemar Wagner; Werner Weiss

2014-01-01T23:59:59.000Z

205

Definition: Heat pump | Open Energy Information  

Open Energy Info (EERE)

pump pump Jump to: navigation, search Dictionary.png Heat pump Heating and/or cooling equipment that, during the heating season, draws heat into a building from outside and, during the cooling season, ejects heat from the building to the outside[1] View on Wikipedia Wikipedia Definition A heat pump is a device that transfers heat energy from a heat source to a heat sink against a temperature gradient. Heat pumps are designed to move thermal energy opposite the direction of spontaneous heat flow. A heat pump uses some amount of external high-grade energy to accomplish the desired transfer of thermal energy from heat source to heat sink. While compressor-driven air conditioners and freezers are familiar examples of heat pumps, the term "heat pump" is more general and applies to

206

Seasonal thermal energy storage  

SciTech Connect (OSTI)

This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

1984-05-01T23:59:59.000Z

207

Livestock Seasonal Price Variation  

E-Print Network [OSTI]

Seasonal price movements can be measured and used to help in marketing livestock. This publication includes 10-year seasonal price indexes for several livestock categories, and explains how to interpret and use the information....

Davis, Ernest E.; Sartwelle III, James D.; Mintert, James R.

1999-09-21T23:59:59.000Z

208

Intertie Open Season  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Improvement (CBPI) Customer Forum Energy Imbalance Market Generator Interconnection Reform Implementation Intertie Initiatives Intertie Open Season Transmission Utilization...

209

Performance of the Second Generation Solar Heating System in the Solar House of the Eindhoven University of Technology  

Science Journals Connector (OSTI)

Summer 1981 a new solar heating system has been installed in the Solar House at the E.U.T. The principal features of the system are Philips VTR 261 evacuated tube collectors, integration of the auxiliary heate...

R. W. G. Bisschops; C. W. J. van Koppen…

1984-01-01T23:59:59.000Z

210

Operation and performance of a 350 kW (100 RT) single-effect/double-lift absorption chiller in a district heating network  

SciTech Connect (OSTI)

The efficiency of combined heat, power, and cold production in total energy systems could be improved significantly if absorption chillers were available that could be driven with limited mass flows of low-temperature hot water. In the case of district heat-driven air conditioning, for example, currently available standard absorption chillers are often not applied because they cannot provide the low hot water return temperature and the specific cooling capacity per unit hot water mass flow that are required by many district heating networks. Above all, a drastic increase in the size of the machine (total heat exchanger area) due to low driving temperature differences if of concern in low-temperature applications. A new type of multistage lithium bromide/water absorption chiller has been developed for the summertime operating conditions of district heating networks. It provides large cooling of the district heating water (some 30 K) and large cooling capacity per unit hot water mass flow. Two pilot plants of this novel absorption chiller were designed within the framework of a joint project sponsored by the German Federal Ministry of Education, Science, Research and Technology (BMBF), a consortium of 15 district heating utilities, and two manufacturers. The plants have been operated since summer 1996 in the district heating networks of Berlin and Duesseldorf. This paper describes the concept, installation, and control strategy of the two pilot plants, and it surveys the performance and operating experience of the plants under varying practical conditions.

Schweigler, C.J.; Preissner, M.; Demmel, S.; Hellmann, H.M.; Ziegler, F.F. [ZAE Bayern, Garching/Munich (Germany)

1998-10-01T23:59:59.000Z

211

ITP Industrial Distributed Energy: Combined Heat & Power Multifamily Performance Program-- Sea Park East 150 kW CHP System  

Broader source: Energy.gov [DOE]

Overview of Sea Park East 150 kilowatt (kW) Combined Heat and Power (CHP) System in Brooklyn, New York

212

Comparative Study of Performance and Combustion Characteristics of Conventional and Low Heat Rejection (Mullite Coated) Diesel Engines  

Science Journals Connector (OSTI)

Tests were performed on a single cylinder, four stroke, direct injection, diesel engine whose piston crown, cylinder head and valves were coated with a 0.5 mm thickness of 3Al2O32SiO2 (mullite) (Al2O3 = 60%, SiO2 = 40%) over a 150 ?m thickness of NiCrAlY bond coat. The working conditions for the conventional engine (without coating) and LHR (mullite coated) engine were kept exactly same to ensure a comparison between the two configurations of the engine. This paper is intended to emphasis on performance and combustion characteristics of conventional and LHR (Mullite coated) diesel engines under identical conditions. Tests were carried out at same operational constraints i.e. air-fuel ratio and engine speed conditions for both conventional engine (without coating) and LHR (mullite coated) engines. The results showed that, there was as much as 1.8 % increasing on brake power for LHR (mullite coated) engine compared to conventional engine (without coating) at full load The average decrease in brake specific fuel consumption in the LHR engine compared with the conventional engine was 1.76 % for full engine load. However, there was increasing on cylinder gas pressure and net heat release rate for LHR engine compared to conventional engine. Also the results revealed that, there was as much as 22% increasing on exhaust gas temperature for LHR engine compared to conventional engine at full engine load.

S B Patond; S A Chaple; P N Shrirao; P I Shaikh

2013-01-01T23:59:59.000Z

213

Simulation study on supply temperature optimization in domestic heat pump systems  

Science Journals Connector (OSTI)

An air-to-water heat pump system for the heating of a one-family home is numerically analysed. The influence of the supply temperature on the seasonal performance factor of the heating system is examined by varying the heating curve. Furthermore, an adaptive control algorithm is studied which lowers the supply temperature according to the actual heating demand. The study includes a variation of control parameters. The different configurations are evaluated with respect to their efficiency (seasonal performance factor) and the comfort (room temperature). In systems with correctly parametrized heating curve controlling the room temperature is likely to be too high because of inner loads and solar gains. Instead of dealing with these gains by lowering the mass flow using thermostatic valves, the supply temperature can be dropped. This has a positive effect on heat pump efficiency because it decreases the total temperature lift. The control algorithm adapts the supply temperature in discrete time steps depending on the position of the thermostatic valve. Special attention has to be paid for the resulting room temperature and its deviation. With the control algorithm presented in this paper, the seasonal performance factor can be increased by up to 0.19, depending on the allowed variability of room temperature. Savings in annual primary energy demand compared to a standard controlling are up to 6.8%.

K. Huchtemann; D. Müller

2013-01-01T23:59:59.000Z

214

Design and Analysis of High-Performance Air-Cooled Heat Exchanger with an Integrated Capillary-Pumped Loop Heat Pipe  

E-Print Network [OSTI]

We report the design and analysis of a high-power air-cooled heat exchanger capable of dissipating over 1000 W with 33 W of input electrical power and an overall thermal resistance of less than 0.05 K/W. The novelty of the ...

McCarthy, Matthew

215

Heat dissipation performance of a high-brightness LED package assembly using high-thermal conductivity filler  

Science Journals Connector (OSTI)

This paper presents a thermal analysis and experimental validation of natural convective heat transfer of a high-brightness light-emitting diode (LED) package assembly. The substrate...

Yung, K C; Liem, H; Choy, H S

2013-01-01T23:59:59.000Z

216

Evaluation of performance of combined heat and power systems with dual power generation units (D-CHP).  

E-Print Network [OSTI]

?? In this research, a new combined heat and power (CHP) system configuration has been proposed that uses two power generation units (PGU) operating simultaneously… (more)

Knizley, Alta Alyce

2013-01-01T23:59:59.000Z

217

The Impact of Refrigerant Charge, Air Flow and Expansion Devices on the Measured Performance of an Air-Source Heat Pump Part I  

SciTech Connect (OSTI)

This paper describes extensive tests performed on a 3-ton R-22 split heat pump in heating mode. The tests contain 150 steady-state performance tests, 18 cyclic tests and 18 defrost tests. During the testing work, the refrigerant charge level was varied from 70 % to 130% relative to the nominal value; the outdoor temperature was altered by three levels at 17 F (-8.3 C), 35 F (1.7 C) and 47 F (8.3 C); indoor air flow rates ranged from 60% to 150% of the rated air flow rate; and the expansion device was switched from a fixed-orifice to a thermal expansion value. Detailed performance data from the extensive steady state cyclic and defrost testing performed were presented and compared.

Shen, Bo [ORNL

2011-01-01T23:59:59.000Z

218

Influences of peripherally-cut twisted tape insert on heat transfer and thermal performance characteristics in laminar and turbulent tube flows  

SciTech Connect (OSTI)

Effects of peripherally-cut twisted tape insert on heat transfer, friction loss and thermal performance factor characteristics in a round tube were investigated. Nine different peripherally-cut twisted tapes with constant twist ratio (y/W = 3.0) and different three tape depth ratios (DR = d/W = 0.11, 0.22 and 0.33), each with three different tape width ratios (WR = w/W = 0.11, 0.22 and 0.33) were tested. Besides, one typical twisted tape was also tested for comparison. The measurement of heat transfer rate was conducted under uniform heat flux condition while that of friction factor was performed under isothermal condition. Tests were performed with Reynolds number in a range from 1000 to 20,000, using water as a working fluid. The experimental results revealed that both heat transfer rate and friction factor in the tube equipped with the peripherally-cut twisted tapes were significantly higher than those in the tube fitted with the typical twisted tape and plain tube, especially in the laminar flow regime. The higher turbulence intensity of fluid in the vicinity of the tube wall generated by the peripherally-cut twisted tape compared to that induced by the typical twisted tape is referred as the main reason for achieved results. The obtained results also demonstrated that as the depth ratio increased and width ratio decreased, the heat transfer enhancement increased. Over the range investigated, the peripherally-cut twisted tape enhanced heat transfer rates in term of Nusselt numbers up to 2.6 times (turbulent regime) and 12.8 times (laminar regime) of that in the plain tube. These corresponded to the maximum performance factors of 1.29 (turbulent regime) and 4.88 (laminar regime). (author)

Eiamsa-ard, Smith [Department of Mechanical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Seemawute, Panida [Department of Civil Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Wongcharee, Khwanchit [Department of Chemical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand)

2010-09-15T23:59:59.000Z

219

The Role of the Ocean in the Seasonal Cycle of the Hadley Circulation  

Science Journals Connector (OSTI)

The influence of ocean heat transport on the seasonal cycle of the Hadley circulation is investigated using idealized experiments with a climate model. It is found that ocean heat transport plays a fundamental role in setting the structure and ...

Amy C. Clement

2006-12-01T23:59:59.000Z

220

Optimal artificial neural network architecture selection for performance prediction of compact heat exchanger with the EBaLM-OTR technique  

SciTech Connect (OSTI)

Artificial Neural Networks (ANN) have been used in the past to predict the performance of printed circuit heat exchangers (PCHE) with satisfactory accuracy. Typically published literature has focused on optimizing ANN using a training dataset to train the network and a testing dataset to evaluate it. Although this may produce outputs that agree with experimental results, there is a risk of over-training or overlearning the network rather than generalizing it, which should be the ultimate goal. An over-trained network is able to produce good results with the training dataset but fails when new datasets with subtle changes are introduced. In this paper we present EBaLM-OTR (error back propagation and Levenberg-Marquardt algorithms for over training resilience) technique, which is based on a previously discussed method of selecting neural network architecture that uses a separate validation set to evaluate different network architectures based on mean square error (MSE), and standard deviation of MSE. The method uses k-fold cross validation. Therefore in order to select the optimal architecture for the problem, the dataset is divided into three parts which are used to train, validate and test each network architecture. Then each architecture is evaluated according to their generalization capability and capability to conform to original data. The method proved to be a comprehensive tool in identifying the weaknesses and advantages of different network architectures. The method also highlighted the fact that the architecture with the lowest training error is not always the most generalized and therefore not the optimal. Using the method the testing error achieved was in the order of magnitude of within 10{sup -5} - 10{sup -3}. It was also show that the absolute error achieved by EBaLM-OTR was an order of magnitude better than the lowest error achieved by EBaLM-THP.

Dumidu Wijayasekara; Milos Manic; Piyush Sabharwall; Vivek Utgikar

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Fall: Energy Saving Changes with the Season | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Fall: Energy Saving Changes with the Season Fall: Energy Saving Changes with the Season Fall: Energy Saving Changes with the Season October 18, 2011 - 6:42am Addthis Andrea Spikes Communicator at DOE's National Renewable Energy Laboratory I'm sure you've noticed the change in seasons by now. Fall brings cooler weather, and with it my thoughts turn to warm things like putting blankets on the couch, enjoying my fireplace, and adjusting my thermostat (as little as possible, of course). One thing we did over the weekend is we insulated our water heater. Depending on how efficient your water heater tank is, adding insulation can reduce standby heat losses by 25%-45% and save you around 4%-9% in water heating costs. Since water heating contributes an average of 18% to the typical home utility bill, it's definitely worth it to add insulation!

222

Impacts of Soil and Pipe Thermal Conductivity on Performance of Horizontal Pipe in a Ground-source Heat Pump  

E-Print Network [OSTI]

In this paper the composition and thermal property of soil are discussed. The main factors that impact the soil thermal conductivity and several commonly-used pipe materials are studied. A model of heat exchanger with horizontal pipes of ground...

Song, Y.; Yao, Y.; Na, W.

2006-01-01T23:59:59.000Z

223

CHP in ESPC: Implementing Combined Heat and Power Technologies Using Energy Savings Performance Contracts (ESPCs): Webinar Transcript  

Broader source: Energy.gov [DOE]

Kurmit Rockwell:Welcome.  I'm Kurmit Rockwell, the ESPC Program Manager for DOE's Federal Energy Management Program.  In this presentation we will introduce you to the basics of combined heat and...

224

Thermal Performance of a Novel Heat Transfer Fluid Containing Multiwalled Carbon Nanotubes and Microencapsulated Phase Change Materials  

E-Print Network [OSTI]

The present research work aims to develop a new heat transfer fluid by combining multiwalled carbon nanotubes (MWCNT) and microencapsulated phase change materials (MPCMs). Stable nanofluids have been prepared using different sizes of multiwalled...

Tumuluri, Kalpana

2011-08-08T23:59:59.000Z

225

Combustion and performance of a diesel engine with preheated Jatropha curcas oil using waste heat from exhaust gas  

Science Journals Connector (OSTI)

Abstract The viscosity and density of CJO (crude Jatropha oil) were reduced by heating it using the heat from exhaust gas of a diesel engine with an appropriately designed helical coil heat exchanger. Experiments were conducted to evaluate the combustion characteristics of a DI (direct injection) diesel engine using PJO (preheated Jatropha oil). It exhibited a marginally higher cylinder gas pressure, rate of pressure rise and heat release rate as compared to HSD (high speed diesel) during the initial stages of combustion for all engine loadings. Ignition delay was shorter for PJO as compared to HSD. The results also indicated that BSFC (brake specific fuel consumption) and EGT (exhaust gas temperature) increased while BTE (brake thermal efficiency) decreased with PJO as compared to HSD for all engine loadings. The reductions in CO2 (carbon dioxide), HC (hydrocarbon) and \\{NOx\\} (nitrous oxide) emissions were observed for PJO along with increased CO (carbon monoxide) emission as compared to those of HSD.

Priyabrata Pradhan; Hifjur Raheman; Debasish Padhee

2014-01-01T23:59:59.000Z

226

A Study of Heat Sink Performance in Air and Soil for Use in a Thermoelectric Energy Harvesting Device  

E-Print Network [OSTI]

conductance of a passive heat sink buried in soil. Introduction Solid state thermoelectric generators offer a battery cell at low power. Sensors and communication devices would use the charged battery to operate

227

Performance Analysis of a Transcritical CO2 Heat Pump Water Heater Incorporating a Brazed-Plate Gas-cooler.  

E-Print Network [OSTI]

??This study focuses on the experimental testing and numerical modeling of a 4.5 kW transcritical CO2 heat pump water heater at Queen’s University in the… (more)

Murray, PORTIA

2015-01-01T23:59:59.000Z

228

Performance improvement of combined cycle power plant based on the optimization of the bottom cycle and heat recuperation  

Science Journals Connector (OSTI)

Many F class gas turbine combined cycle (GTCC) power plants are built in ... the efficiency improvement of GTCC plant. A combined cycle with three-pressure reheat heat recovery steam ... HRSG inlet gas temperatur...

Wenguo Xiang; Yingying Chen

2007-03-01T23:59:59.000Z

229

Ductless Heat Pumps  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Water Heaters Showerheads Residential Weatherization Performance Tested Comfort Systems Ductless Heat Pumps New Construction Residential Marketing Toolkit Retail Sales...

230

Heat Pump Water Heaters  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Water Heaters Showerheads Residential Weatherization Performance Tested Comfort Systems Ductless Heat Pumps New Construction Residential Marketing Toolkit Retail Sales...

231

Film cooling performance and heat transfer over an inclined film-cooled surface at different divergent angles with respect to highly turbulent mainstream  

SciTech Connect (OSTI)

Experiments have been performed to study and obtain the adiabatic wall film cooling effectiveness and the heat transfer over a film-cooled surface that is made inclined at various angles with respect to a highly turbulent flow. The vertical temperature distribution was measured to infer the flow structure and the rate of mixing of film jet with the freestream. The freestream turbulence intensity is controlled to range from 1.0% to 26.4%, the inclination or the divergent angle of the film-cooled surface ranges from 0 to 20 , the blowing parameter from 0.5 to 2.0. It is found that the mixing of the film jet with the freestream is significantly enhanced by both the freestream turbulence intensity and the divergent angle of the film-cooled surface, which leads to the decrease in the film cooling effectiveness and the increase in the heat transfer. However, the inclination angle has more effect on the film cooling performance while the turbulence intensity has more effect on the heat transfer under the film. More detailed discussion is presented. Correlations for both the film cooling effectiveness and the heat transfer under the film-cooled surface have been very successful and are provided. (author)

Yang, Chih-Sheng [Department of Computer Science and Information Engineering Far East University (China); Lin, C.L.; Gau, C. [Institute of Aeronautics and Astronautics, Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan 70101 (China)

2008-05-15T23:59:59.000Z

232

Seasonal Landscape Maintenance  

E-Print Network [OSTI]

Seasonal Landscape Maintenance Oklahoma State University, in compliance with Title VI and VII State University's Department of Horticulture and Landscape Architecture and Oklahoma Cooperative to dry between watering allows plants to develop stronger, deeper roots. However, some landscape plants

Balasundaram, Balabhaskar "Baski"

233

Performance of a Heat Pump Water Heater in the Hot-Humid Climate, Windermere, Florida (Fact Sheet), Building America Case Study: Technology Solutions for New and Existing Homes, Building Technologies Office (BTO)  

Broader source: Energy.gov (indexed) [DOE]

Performance of a Performance of a Heat Pump Water Heater in the Hot-Humid Climate Windermere, Florida Over recent years, heat pump water heaters (HPWHs) have become more read- ily available and more widely adopted in the marketplace. A key feature of an HPWH unit is that it is a hybrid system. When conditions are favorable, the unit will operate in heat pump mode (using a vapor compression system that extracts heat from the surrounding air) to efficiently provide domestic hot water (DHW). Homeowners need not adjust their behavior to conform to the heat pump's capabilities. If a heat pump cannot meet a higher water draw demand, the heater will switch to electric resistance to provide a higher heating rate. This flexibility

234

A Bayesian approach to forecast intermittent demand for seasonal products  

Science Journals Connector (OSTI)

This paper investigates the forecasting of a large fluctuating seasonal demand prior to peak sale season using a practical time series, collected from the US Census Bureau. Due to the extreme natural events (e.g. excessive snow fall and calamities), sales may not occur, inventory may not replenish and demand may set off unrecorded during the peak sale season. This characterises a seasonal time series to an intermittent category. A seasonal autoregressive integrated moving average (SARIMA), a multiplicative exponential smoothing (M-ES) and an effective modelling approach using Bayesian computational process are analysed in the context of seasonal and intermittent forecast. Several forecast error indicators and a cost factor are used to compare the models. In cost factor analysis, cost is measured optimally using dynamic programming model under periodic review policy. Experimental results demonstrate that Bayesian model performance is much superior to SARIMA and M-ES models, and efficient to forecast seasonal and intermittent demand.

Mohammad Anwar Rahman; Bhaba R. Sarker

2012-01-01T23:59:59.000Z

235

Simulation study on lignite-fired power system integrated with flue gas drying and waste heat recovery – Performances under variable power loads coupled with off-design parameters  

Science Journals Connector (OSTI)

Abstract Lignite is a kind of low rank coal with high moisture content and low net heating value, which is mainly used for electric power generation. However, the thermal efficiency of power plants firing lignite directly is very low. Pre-drying is a proactive option, dehydrating raw lignite to raise its heating value, to improve the power plant thermal efficiency. A pre-dried lignite-fired power system integrated with boiler flue gas drying and waste heat recovery was proposed in this paper. The plant thermal efficiency could be improved by 1.51% at benchmark condition due to pre-drying and waste heat recovery. The main system performances under variable power loads were simulated and analyzed. Simulation results show that the improvement of plant thermal efficiency reduced to 1.36% at 50% full load. Moreover, the influences of drying system off-design parameters were simulated coupled with power loads. The variation tendencies of main system parameters were obtained. The influence of pre-drying degree (including moisture content of pre-dried lignite and raw lignite) on the plant thermal efficiency diminishes gradually with the decreasing power load. The dryer thermal efficiency and dryer exhaust temperature are also main factors and the influences on system parameters have been quantitatively analyzed.

Xiaoqu Han; Ming Liu; Jinshi Wang; Junjie Yan; Jiping Liu; Feng Xiao

2014-01-01T23:59:59.000Z

236

Performance model and annual yield comparison of parabolic-trough solar thermal power plants with either nitrogen or synthetic oil as heat transfer fluid  

Science Journals Connector (OSTI)

Abstract The majority of commercial parabolic-trough plants in the world operate with synthetic oil as heat transfer fluid in the solar field. However, the synthetic oils that are available at affordable cost present some challenges such as their flammability, environmental toxicity and a temperature limitation of around 400 °C. As alternative, this work proposes the use of pressurized nitrogen as heat transfer fluid. In order to analyze the feasibility of this technology, a comparison between a plant with nitrogen and a conventional plant with synthetic oil has been carried out. In both cases, 50 MWe parabolic-trough plants with 6 h of thermal storage are used as reference. A performance model including the solar field, the thermal storage system and the power block has been developed for each plant in the TRNSYS simulation software. This paper also describes the specifications, design and sizing of the solar field and explains the basic operation strategy applied in each model. Both annual simulations have been performed considering the same location, Almería (Spain), and meteorological data. In summary, the results show that similar net annual electricity productions can be attained for parabolic-trough plants with the same collection area using either nitrogen or synthetic oil as heat transfer fluid.

Mario Biencinto; Lourdes González; Eduardo Zarza; Luis E. Díez; Javier Muñoz-Antón

2014-01-01T23:59:59.000Z

237

The effects of airflow modulation and multi-stage defrost on the performance of an air source heat pump  

E-Print Network [OSTI]

with total refrigerant charge of 950 grams (2. 1 lbs) (Tanaka et. al. 1982). Table 2. 1 shows the distribution of refrigerant during steady state heating and cooling operation. Table 2. 1: Refri erant Distribution at Stead State Location Hestin made... light, (2) keep the charge as low as possible, (3) stop refrigerant flow into the outdoor coil during off periods, and (4) protect the compressor from slugging liquid. The work of the previously mentioned investigators has shown that the degradation...

Payne, William Vance

2012-06-07T23:59:59.000Z

238

Project Profile: Halide and Oxy-Halide Eutectic Systems for High-Performance, High-Temperature Heat Transfer Fluids  

Broader source: Energy.gov [DOE]

The University of Arizona along with partners at Arizona State University and Georgia Institute of Technology, under the 2012 Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids funding opportunity, is investigating the use of halide salts with oxy-halide additives as a heat transfer fluid (HTF) in concentrating solar power (CSP) systems operating at temperatures greater than 800°C. By allowing higher temperature operation, CSP systems can achieve greater efficiencies and thereby reduce the overall system cost.

239

SUPERGLASS. Engineering field tests - Phase 3. Production, market planning, and product evaluation for a high-thermal-performance insulating glass design utilizing HEAT MIRROR transparent insulation. Final report  

SciTech Connect (OSTI)

HEAT MIRROR transparent window insulation consists of a clear polyester film two mils (.002'') thick with a thin, clear low-emissivity (.15) coating deposited on one side by state-of-the-art vacuum deposition processes. This neutral-colored invisible coating reflects long-wave infrared energy (heat). When mounted by being stretched with a 1/2'' air-gap on each side of the film, the resulting unit reduces heat loss by 60% compared to dual insulating glass. Southwall Corporation produces HEAT MIRROR transparent insulation and markets it to manufacturers of sealed insulating glass (I.G.) units and window and building manufacturers who make their own I.G. These companies build and sell the SUPERGLASS sealed glazing units. Units made and installed in buildings by six customers were visited. These units were located in many geographic regions, including the Pacific Northwest, Rocky Mountains, New England, Southeast, and West Coast. As much as could be obtained of their history was recorded, as was their current condition and performance. These units had been in place from two weeks to over a year. All of the units were performing thermally very well, as measured by taking temperature profiles through them and through adjacent conventional I.G. units. Some units had minor visual defects (attributed to I.G. assembly techniques) which are discussed in detail. Overall occupant acceptance was enthusiastically positive. In addition to saving energy, without compromise of optical quality or appearance, the product makes rooms with large glazing areas comfortable to be in in cold weather. All defects observed were present when built; there appears to be no in-field degradation of quality at this time.

Tilford, C L

1982-11-01T23:59:59.000Z

240

RTO heat recovery system decreases production costs and provides payback  

SciTech Connect (OSTI)

Application of a heat recovery system to an existing regenerative thermal oxidizer (RTO) was considered, tested, and selected for decreasing production costs at a pressure sensitive tape manufacturing facility. Heat recovery systems on RTO's are less common than those on other thermal oxidizers (e.g., recuperative) because RTO's, by the nature of the technology, usually provide high thermal efficiencies (without the application of external heat recovery systems). In this case, the production processes were integrated with the emission controls by applying an external heat recovery system and by optimizing the design and operation of the existing drying and cure ovens, RTO system, and ductwork collection system. Integration of these systems provides an estimated annual production cost savings of over $400,000 and a simplified capital investment payback of less than 2 years, excluding possible savings from improved dryer operations. These additional process benefits include more consistent and simplified control of seasonal dryer performance and possibly production throughput increases. The production costs savings are realized by substituting excess RTO heat for a portion of the infrared (IR) electrical heat input to the dryers/ovens. This will be accomplished by preheating the supply air to the oven zones with the excess RTO heat (i.e., heat at the RTO exceeding auto-thermal conditions). Several technologies, including direct air-to-air, indirect air-to-air, hot oil-to-air, waste heat boiler (steam-to-air) were evaluated for transferring the excess RTO heat (hot gas) to the ovens. A waste heat boiler was selected to transfer the excess RTO heat to the ovens because this technology provided the most economical, reliable, and feasible operation. Full-scale production test trials on the coating lines were performed and confirmed the IR electrical costs could be reduced up to 70%.

Lundquist, P.R.

1999-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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-pipe-coupled planar thermionic converter: Performance characterization, nondestructive testing, and evaluation. Final report, 1 Aug 90-30 Nov 91  

SciTech Connect (OSTI)

This report provides the technical details on the research activities conducted by Wright Laboratory and UES, Inc. personnel during the period of August 1990 to November 1991. The performance of two heat pipe coupled, planar thermionic energy converters was characterized using experimental and analytical methods. Nondestructive failure analysis was performed to evaluate the causes for the failure of a molybdenum-rhenium converter. The experimentation was carded out at the thermionic facilities at the USAF Wright Laboratory while the computer simulations were performed at Wright Laboratory and the University of Central Florida. A maximum current density of 10.1 amps/cm[sup 2] and a peak power density of 7.7 watts/cm[sup 2] were obtained from the rhenium-rhenium diode operating in the ignited mode.

Young, T.J.; Lamp, T.R.; Tsao, B.H.; Ramalingam, M.L.

1992-03-15T23:59:59.000Z

242

Building America Webinar: Retrofitting Central Space Conditioning Strategies for Multifamily Buildings- Control strategies to improve hydronic space heating performance  

Broader source: Energy.gov [DOE]

This webinar was presented on July 16, 2014, and provided information about improving the performance of central space conditioning systems in multifamily buildings.

243

HEAT TRANSFER FLUIDS  

E-Print Network [OSTI]

The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

Lenert, Andrej

2012-01-01T23:59:59.000Z

244

Effects of refrigerant charge and structural parameters on the performance of a direct-expansion solar-assisted heat pump system  

Science Journals Connector (OSTI)

Abstract The direct-expansion solar-assisted heat pump (DX-SAHP) is widely studied as a refrigeration system, which can supply hot water for domestic use during the whole year. The system refrigerant charge and structure parameters are believed to have a great effect on the cycling thermal performance. The refrigerant mass charge including two-phase and single-phase in heat exchangers and pipes is calculated with distributed and lumped parameter approach mathematical models, respectively. Based on the system simulation program, the refrigerant distribution characteristics and system performance under varied structural parameters are obtained. The mathematical calculation results show that the 70%–80% refrigerant charge exists in the condenser and collector; the optimum refrigerant charge, solar collector area, condenser pipe length and condenser internal diameter for the system are 1.65–1.75 kg, 6.0 m2, 70 m and 9 mm, respectively. In the optimum parameters, the better system performance and feasible cost can be achieved.

D. Zhang; Q.B. Wu; J.P. Li; X.Q. Kong

2014-01-01T23:59:59.000Z

245

An Analysis of Efficiency Improvements in Residential Sized Heat Pumps, Final Report, May 1986  

E-Print Network [OSTI]

EQUIPMENT MANUFACTURERS ORNL OAK RIDGE NATIONAL LABORATORY PLF PART LOAD FACTOR SAI SCIENCE APPLICATION INCORPORATED SEER SEASONAL ENERGY EFFICIENCY RATIO SF SQUARE FEET SHF SENSIBLE HEATING FACTOR TDB DRY BULB TEMPERATURE TON 12000 BTU/HR TXV THERMAL... Systems 6-13 5 Ton Package Systems 6-22 References 6-22 CONCLUSIONS AND RECOMMENDATIONS 7-1 iii APPENDIX * PAGE A ORNL MODEL OUTPUT A-1 B SEASONAL PERFORMANCE MODEL DESCRIPTION B-1 C OPTIMIZATION PROCEDURE C-1 iv CHAPTER 1 INTRODUCTION The National Energy...

O'Neal, D. L.; Murphy, W. E.

1985-01-01T23:59:59.000Z

246

Building America Webinar: High Performance Space Conditioning Systems, Part I: Heating and Cooling with Mini-Splits in the Northeast  

Broader source: Energy.gov [DOE]

This presentation was delivered at the U.S. Department of Energy Building America webinar, High Performance Space Conditioning Systems, Part I, conducted on October 23, 2014, by Kohta Ueno of Building Science Corporation.

247

Heat Pump Systems | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Pump Systems Pump Systems Heat Pump Systems May 16, 2013 - 5:33pm Addthis A heat pump can provide an alternative to using your air conditioner. | Photo courtesy of iStockPhoto/LordRunar. A heat pump can provide an alternative to using your air conditioner. | Photo courtesy of iStockPhoto/LordRunar. What does this mean for me? Heat pumps can supply heat, cooling, and hot water. Your climate and site will determine the type of heat pump most appropriate for your home. For climates with moderate heating and cooling needs, heat pumps offer an energy-efficient alternative to furnaces and air conditioners. Like your refrigerator, heat pumps use electricity to move heat from a cool space to a warm space, making the cool space cooler and the warm space warmer. During the heating season, heat pumps move heat from the cool outdoors into

248

Winter Residential Heating Oil Prices  

Gasoline and Diesel Fuel Update (EIA)

7 7 Notes: Residential heating oil prices reflect a similar pattern to that shown in spot prices. However, like other retail petroleum prices, they tend to lag changes in wholesale prices in both directions, with the result that they don't rise as rapidly or as much, but they take longer to recede. This chart shows the residential heating oil prices collected under the State Heating Oil and Propane Program (SHOPP), which only runs during the heating season, from October through March. The spike in New York Harbor spot prices last winter carried through to residential prices throughout New England and the Central Atlantic states. Though the spike actually lasted only a few weeks, residential prices ended the heating season well above where they had started.

249

Four seasons of giving  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Kurt's Column Kurt's Column Community Connections: Our link to Northern New Mexico Communities Latest Issue:Dec. 2013 - Jan. 2014 All Issues » submit Four seasons of giving We value a culture of giving and appreciate our employees' on-going volunteerism throughout Northern New Mexico and even nationwide. January 1, 2013 dummy image Read our archives. Contacts Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email We value a culture of giving and appreciate our employees' on-going volunteerism throughout Northern New Mexico and even nationwide. So, as the Lab, its employees, and retirees wrap up this year's season, I'm happy to say this is not our only time of giving. Programs such as our Science Education Community Service Time efforts mean that whenever school is in

250

Passive solar space heating  

SciTech Connect (OSTI)

An overview of passive solar space heating is presented indicating trends in design, new developments, performance measures, analytical design aids, and monitored building results.

Balcomb, J.D.

1980-01-01T23:59:59.000Z

251

Solar Swimming Pool Heating in Pakistan  

Science Journals Connector (OSTI)

Hotels and swimming clubs in Pakistan pay huge gas bills for heating Swimming pools in winter. Winter days in most parts ... solar collectors may be used to extend the swimming season. Installing the pool in a wi...

Irshad Ahmad; Nasim A Khan

2009-01-01T23:59:59.000Z

252

Heating, Ventilating, and Air-Conditioning: Recent Advances in Diagnostics and Controls to Improve Air-Handling System Performance  

SciTech Connect (OSTI)

The performance of air-handling systems in buildings needs to be improved. Many of the deficiencies result from myths and lore and a lack of understanding about the non-linear physical principles embedded in the associated technologies. By incorporating these principles, a few important efforts related to diagnostics and controls have already begun to solve some of the problems. This paper illustrates three novel solutions: one rapidly assesses duct leakage, the second configures ad hoc duct-static-pressure reset strategies, and the third identifies useful intermittent ventilation strategies. By highlighting these efforts, this paper seeks to stimulate new research and technology developments that could further improve air-handling systems.

Wray, Craig; Wray, Craig P.; Sherman, Max H.; Walker, I.S.; Dickerhoff, D.J.; Federspiel, C.C.

2008-02-01T23:59:59.000Z

253

A comparative evaluation of Al 2 O 3 coated low heat rejection diesel engine performance and emission characteristics using fuel as rice bran and pongamia methyl ester  

Science Journals Connector (OSTI)

In this study for the first time a nanoceramic Al 2 O 3 was used as a coatingmaterial in the low heat rejection engine concept. Experiments were conducted on single cylinder four stroke water cooled and direct injection diesel engine. First the engine was tested at different load conditions without coating. Then combustion chamber surfaces (cylinder head cylinder liner valves and piston crown face) were coated with nanoceramic material of Al 2 O 3 using plasma spray method. Comparative evaluation on performance and emission characteristics using fuel as rice bran methyl ester pongamia methyl ester and biodiesel/diesel fuel mixtures was studied in the ceramiccoated and uncoated engines under the same running conditions. An increase in engine power and a decrease in specific fuel consumption as well as significant improvements in exhaust gas emissions (except NOx) and smoke density were observed in the ceramiccoated engines compared with those of the uncoated engine.

M. Mohamed Musthafa; S. P. Sivapirakasam; M. Udayakumar

2010-01-01T23:59:59.000Z

254

Geothermal Heat Pump Basics | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Heat Pump Basics Heat Pump Basics Geothermal Heat Pump Basics August 19, 2013 - 11:12am Addthis Text Version Geothermal heat pumps use the constant temperature of the earth as an exchange medium for heat. Although many parts of the country experience seasonal temperature extremes-from scorching heat in the summer to sub-zero cold in the winter-the ground a few feet below the earth's surface remains at a relatively constant temperature. Depending on the latitude, ground temperatures range from 45°F (7°C) to 75°F (21°C). So, like a cave's, the ground's temperature is warmer than the air above it during winter and cooler than the air above it in summer. Geothermal heat pumps take advantage of this by exchanging heat with the earth through a ground heat exchanger. Geothermal heat pumps are able to heat, cool, and, if so equipped, supply

255

Surveillance Guide - MAS 10.3 Seasonal Preparation  

Broader source: Energy.gov (indexed) [DOE]

SEASONAL PREPARATION SEASONAL PREPARATION 1.0 Objective The objective of this surveillance is to verify that the contractor is implementing appropriate measures to protect equipment and systems from damage due to the effects of cold weather. The Facility Representative evaluates systems necessary for the protection of the public and workers to determine if they have been adequately prepared for cold weather. The Facility Representative also examines other preparations for cold weather to ensure that materials are properly stored, permanent and auxiliary heating systems are functional, and other appropriate preparations have been completed. During the surveillance, the Facility Representative ensures that applicable DOE requirements have been implemented.

256

Consumer Winter Heating Oil Costs  

Gasoline and Diesel Fuel Update (EIA)

6 6 Notes: The outlook for heating oil costs this winter, due to high crude oil costs and tight heating oil supplies, breaks down to an expected increase in heating expenditures for a typical oil-heated household of more than $200 this winter, the result of an 18% increase in the average price and an 11% increase in consumption. The consumption increase is due to the colder than normal temperatures experienced so far this winter and our expectations of normal winter weather for the rest of this heating season. Last winter, Northeast heating oil (and diesel fuel) markets experienced an extremely sharp spike in prices when a severe weather situation developed in late January. It is virtually impossible to gauge the probability of a similar (or worse) price shock recurring this winter,

257

Recovery Act-Funded Geothermal Heat Pump projects | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Geothermal Heat Pump Geothermal Heat Pump projects Recovery Act-Funded Geothermal Heat Pump projects The U.S. Department of Energy (DOE) was allocated funding from the American Recovery and Reinvestment Act to conduct research into ground source heat pump technologies and applications. Projects funded by the Recovery Act include: Historic Train Depot with a Hybrid System Funding amount: $1.7 million 1001 South 15th Street Associates LLC - New School and Performing Arts Theater The facility is a 23,000 square foot historic train depot requiring a GHP with 206 tons of cooling capacity. The hybrid GHP system incorporates a dry cooler to improve efficiency and life cycle effectiveness of the system by seasonally rebalancing the ground temperature. Grants Award Summary Massive Project with Massive Job Creation and Carbon Savings

258

E-Print Network 3.0 - advanced heat process Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Heat Transfer Performance... ) Heat Transfer Solid Mechanics Energy Systems Air-Conditioner Performance Evaluations Alternate... and Diagnostic Center...

259

Retail Heating Oil and Diesel Fuel Prices  

Gasoline and Diesel Fuel Update (EIA)

6 6 Notes: With the worst of the heating season (October-March) now behind us, we can be fairly confident that retail heating oil prices have seen their seasonal peak. Relatively mild weather and a softening of crude oil prices have helped ease heating oil prices. Spot heating oil prices recently reached their lowest levels in over six months. Because of relatively balmy weather in the Northeast in January and February, heating oil stock levels have stabilized. Furthermore, heating oil production has been unusually robust, running several hundred thousand barrels per day over last year's pace. Currently, EIA expects winter prices to average around $1.41, which is quite high in historical terms. The national average price in December 2000 was 44 cents per gallon above the December 1999 price. For February

260

Energy Performance and Economic Evaluations of the Geothermal Heat Pump System used in the KnowledgeWorks I and II Buildings, Blacksburg, Virginia.  

E-Print Network [OSTI]

??Heating, Ventilating and Air Conditioning Systems (HVAC) are not only one of the most energy consuming components in buildings but also contribute to green house… (more)

Charoenvisal, Kongkun

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

Thermoelectrics Partnership: High Performance Thermoelectric...  

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

High Performance Thermoelectric Waste Heat Recovery System Based on Zintl Phase Materials with Embedded Nanoparticles Thermoelectrics Partnership: High Performance Thermoelectric...

262

Performance Tested Comfort Systems  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Showerheads Residential Weatherization Performance Tested Comfort Systems Ductless Heat Pumps New Construction Residential Marketing Toolkit Retail Sales Allocation Tool...

263

New energy and exergy parameters for geothermal district heating systems  

Science Journals Connector (OSTI)

This paper introduces four new parameters, namely energetic renewability ratio, exergetic renewability ratio, energetic reinjection ratio, and exergetic reinjection ratio for geothermal district energy systems. These parameters are applied to Edremit Geothermal District Heating System (GDHS) in Balikesir, Turkey for daily, monthly and yearly assessments and their variations are studied. In addition, the actual data are regressed to obtain some applied correlations for practical use. Some results follow: (i) Both energetic and exergetic renewability ratios decrease with decreasing temperature in heating season and increasing temperature in the summer. (ii) Both energetic and exergetic reinjection ratios increase with decreasing temperature for heating season and increase with increasing temperature for summer season.

C. Coskun; Zuhal Oktay; I. Dincer

2009-01-01T23:59:59.000Z

264

Active Solar Heating | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Active Solar Heating Active Solar Heating Active Solar Heating June 24, 2012 - 5:58pm Addthis This North Carolina home gets most of its space heating from the passive solar design, but the solar thermal system supplies both domestic hot water and a secondary radiant floor heating system. | Photo courtesy of Jim Schmid Photography, NREL This North Carolina home gets most of its space heating from the passive solar design, but the solar thermal system supplies both domestic hot water and a secondary radiant floor heating system. | Photo courtesy of Jim Schmid Photography, NREL What does this mean for me? If you live in a cold climate and have unobstructed access to the sun during the heating season, an active solar heating system might make sense for you. You can buy a manufactured active solar system or build your own.

265

Performance of solar assisted heatpump systems in residential applications  

Science Journals Connector (OSTI)

In this experimental study, several solar-assisted heating and cooling configurations have beenconsidered for a basic system comprised of a two-speed heat pump, photovoltaic (PV) arrays, solar thermal collectors, and thermal storage. The objective of the study was to determine the performance of the PV arrays at decreased insolation, the effects of air preheat by solar thermal energy on heat pump operation, and cooling system performance under two different configurations. During the entire operation, the PV arrays converted 4.7 per cent (9.5 MWh) of the incident solar insolation to d.c. power, of which 54.6 per cent was used by the residence. This contributed 23.4 per cent of the total house electrical demand. The remaining 45.4 per cent of the output was fed to the utility, indicating the arrays and the heat pump were not properly sized with each other. Based on results from the winter heating operation, it is shown that for the particular heating system consdered, the best performance is attained when the solar heating is used alone. By using the heat pump as a booster, the remaining available solar energy left in the storage tank can be used with good seasonal performance factor. Summer cooling operation consisted of two sequential cooling configurations. In the first cooling test, the heat pump was operated to either the house or storage when the PV array generation level was greater than the energy demand of the heat pump and associated equipment. When the array output level was less than the cooling system demand, the operating strategy was that of an off-peak cooling operation to chill the water storage. Utilization of chilled water storage was not realized in the first cooling test because of the inherent inefficient design of the Tri-X coil. The capacity at low-speed heat pump operation was too small to effect significant cooling of the water loop; whereas high-speed heat pump operation in attempting to chill water (fan operation absent) caused frosting of the coil. The heat pump was utilized only to maintain chilled water storage in the second cooling test, without heat transfer through the Tri-X coil. Cooling system performance obtained in cooling test 2 using the Ametex exchanger was considerably improved over the test 2 performance with the Tri-X coil.

S. Kugle; S. Green; A. Haji-Sheikh; D.Y.S. Lou

1984-01-01T23:59:59.000Z

266

Atlantic Hurricane Season of 2008  

Science Journals Connector (OSTI)

The 2008 Atlantic hurricane season is summarized and the year’s tropical cyclones are described. Sixteen named storms formed in 2008. Of these, eight became hurricanes with five of them strengthening into major hurricanes (category 3 or higher on ...

Daniel P. Brown; John L. Beven; James L. Franklin; Eric S. Blake

2010-05-01T23:59:59.000Z

267

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 heating season is typically about 10 cents per gallon. Exceptions occur in unusual circumstances, such as very cold weather, large changes in crude oil prices, or supply problems. Heating oil prices for East Coast consumers started this winter at just over $1 per gallon, but rising crude oil prices drove them up nearly 21 cents through mid-January. With the continuing upward pressure from crude oil markets, magnified by a regional shortfall of heating oil

268

Geothermal Heat Pumps- Heating Mode  

Broader source: Energy.gov [DOE]

In winter, fluid passing through this vertical, closed loop system is warmed by the heat of the earth; this heat is then transferred to the building.

269

Seasonality in the Natural Gas Balancing Item: Historical Trends and  

Gasoline and Diesel Fuel Update (EIA)

Analysis > Seasonality in the Natural Gas Balancing Item: Historical Trends and Corrective Measures Analysis > Seasonality in the Natural Gas Balancing Item: Historical Trends and Corrective Measures Seasonality in the Natural Gas Balancing Item: Historical Trends and Corrective Measures Released: June 4, 2010 Download Full Report (PDF) This special report examines an underlying cause of the seasonal pattern in the balancing item published in the Natural Gas Monthly. Research finds that a significant portion of data collected on EIA’s primary monthly natural gas consumption survey reflects billing data that does not strictly coincide with the actual calendar month, which creates an aggregate-level discrepancy with EIA’s other natural gas supply and disposition data series. This discrepancy is especially observable during the fall and spring as one transitions into and out of the winter heating season. The report also outlines improved data collection and estimation procedures that will be implemented later this year to more closely align reported and actual calendar month consumption. This discussion will be helpful to users of EIA’s volumetric natural gas data. Questions about this report should be directed to Andy Hoegh at andrew.hoegh@eia.doe.gov or (202) 586-9502.

270

Building America Technology Solutions for New and Existing Homes: Field Performance of Heat Pump Water Heaters in the Northeast (Fact Sheet)  

Broader source: Energy.gov [DOE]

In this project, the Consortium for Advanced Residential Buildings evaluated three newly released heat pump water heater products in order to provide publicly available field data on these products.

271

A ground-coupled storage heat pump system with waste heat recovery  

SciTech Connect (OSTI)

This paper reports on an experimental single-family residence that was constructed to demonstrate integration of waste heat recovery and seasonal energy storage using both a ventilating and a ground-coupled heat pump. Called the Idaho energy Conservation Technology House, it combines superinsulated home construction with a ventilating hot water heater and a ground coupled water-to-water heat pump system. The ground heat exchangers are designed to economically promote seasonal and waste heat storage. Construction of the house was completed in the spring of 1989. Located in Moscow, Idaho, the house is occupied by a family of three. The 3,500 ft{sup 2} (325 m{sup 2}) two-story house combines several unique sub-systems that all interact to minimize energy consumption for space heating and cooling, and domestic hot water.

Drown, D.C.; Braven, K.R.D. (Univ. of Idaho, ID (US)); Kast, T.P. (Thermal Dynamic Towers, Boulder, CO (US))

1992-02-01T23:59:59.000Z

272

Numerical Evaluation of Flow and Heat Transfer in Plate-Pin Fin Heat Sinks with Various Pin Cross-Sections  

E-Print Network [OSTI]

Liu, Research on the Heat Transfer and Flow Performance of aCompound Heat Sink, Numer. Heat Transfer A, vol. 55, no. 5,Hand- book of Numerical Heat Transfer, 2nd ed. , chap. 6,

Zhou, Feng; Catton, Ivan

2011-01-01T23:59:59.000Z

273

Energy efficiency improvements utilising mass flow control and a ring topology in a district heating network  

Science Journals Connector (OSTI)

Abstract Heating and cooling have a major role in the energy sector, covering 46% of total final energy use worldwide. District heating (DH) is a significant technology for improving the energy efficiency of heating systems in communities, because it enables waste heat sources to be utilised economically and therefore significantly reduces the environmental impacts of power generation. As a result of new and more stringent construction regulations for buildings, the heat demands of individual buildings are decreasing and more energy-efficient heating systems have to be developed. In this study, the energy efficiency of a new DH system which includes both a new control system called mass flow control and a new network design called a ring network is examined. A topology in the Helsinki region is studied by using a commercial DH network modelling tool, Grades Heating. The district heating network is attached to a wood-burning heat station which has a heat recovery system in use. Examination is performed by means of both technical and economic analysis. The new non-linear temperature programme that is required is adopted for supply and return temperatures, which allows greater temperature cooling and smaller flow rates. Lower district heating water temperatures are essential when reducing the heat losses in the network and heat production. Mass flow control allows smaller pressure drops in the network and thus reduces the pumping power. The aim of this study was to determine the most energy-efficient DH water supply temperatures in the case network. If the ring network design is utilised, the district heating system is easier to control. As a result the total heat consumption within the heating season is reduced compared to traditional DH systems. On the basis of the results, the new DH system is significantly more energy-efficient in the case network that was examined than the traditional design. For example, average energy losses within the constraints (which consist of heat losses, pumping energy, and surplus energy from the heat recovery system) are reduced from 4.4% to 3.1%.

Tatu Laajalehto; Maunu Kuosa; Tapio Mäkilä; Markku Lampinen; Risto Lahdelma

2014-01-01T23:59:59.000Z

274

Experimental analysis of a direct expansion solar assisted heat pump with integral storage tank for domestic water heating under zero solar radiation conditions  

Science Journals Connector (OSTI)

This paper deals with the experimental evaluation of the performance of a direct expansion solar assisted heat pump water heating (DX-SAHPWH) system working under zero solar radiation conditions at static heating operation mode of the storage tank. The DX-SAHPWH system includes two bare solar collectors as evaporator, a \\{R134a\\} rotary-type hermetic compressor, a thermostatic expansion valve and a helical coil condenser immersed in a 300 L water storage tank. The zero solar radiation and stable ambient air temperature working conditions were established by placing the solar collectors into a climate chamber. The analysis is based on experimental data taken from the DX-SAHPWH provided by the manufacturer and equipped with an appropriate data acquisition system. In the paper, the experimental facility, the data acquisition system and the experimental methodology are described. Performance parameters to evaluate the energy efficiency, such as COP and equivalent seasonal performance factors (SPFe) for the heating period, and the water thermal stratification in the storage tank are defined and obtained from the experimental data. Results from the experimental analysis under transient operating working conditions of the DX-SAHPWH system and its main components are shown and discussed. Lastly, the Huang and Lee DX-SAHPWH performance evaluation method was applied resulting in a characteristic COP of 3.23 for the DX-SAHPWH system evaluated under zero solar radiation condition.

José Fernández-Seara; Carolina Piñeiro; J. Alberto Dopazo; F. Fernandes; Paulo X.B. Sousa

2012-01-01T23:59:59.000Z

275

Regional Residential Heating Oil Prices  

Gasoline and Diesel Fuel Update (EIA)

Slide 2 of 11 Notes: 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 7, 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 heating season is typically about 10 cents per gallon. Exceptions occur in unusual circumstances, such as very cold weather, large changes in crude oil prices, or supply problems. Heating oil prices for East Coast consumers started this winter at just over $1 per gallon, but rising crude oil prices drove them up nearly 21 cents per gallon through mid-January. With the continuing upward pressure from crude oil markets, magnified by a regional shortfall of

276

MERLOT: a model for flow and heat transfer through porous media for high heat flux applications  

E-Print Network [OSTI]

MERLOT: a model for flow and heat transfer through porous media for high heat flux applications A Abstract Fusion power plant studies have found helium to be an attractive coolant based on its safety tend to provide modest heat transfer performance due to their inherently low heat capacity and heat

Raffray, A. René

277

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...

278

Status report on survey of alternative heat pumping technologies  

SciTech Connect (OSTI)

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

279

Estimation of changes in energy consumption for heat supply due to interannual temperature variability in the south of the Ukraine  

Science Journals Connector (OSTI)

The influence of low-frequency variability of average over the heating season air temperature on population demands in heat supply is considered. Based on monthly mean temperature values for the period from 18...

A. Kh. Degterev; L. N. Degtereva

2008-11-01T23:59:59.000Z

280

Molecular heat pump  

E-Print Network [OSTI]

We propose a novel molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation waveforms, thus making it possible to optimize the device performance.

Dvira Segal; Abraham Nitzan

2005-10-11T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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

CHAPTER XVI - TIME SERIES: SEASONAL FLUCTUATIONS  

Science Journals Connector (OSTI)

Publisher Summary This chapter discusses the seasonal fluctuations in time series. Seasonal variations are defined either to be studied separately or—more often—to be removed, thus, allowing concentrating on the remaining variation. If the annual data are not strongly influenced by trend movements or cyclical changes, it is possible to compare seasonal data usually—monthly data with averages not adjusted for trend and express them as percentages of these averages. In reality, the amplitude and period of seasonal movements vary in most cases from year to year, being affected by seasonal as well as by cyclical, random, and other nonseasonal factors. The averages, expressed in percentages, thus obtained are preliminary seasonal indexes. Seasonal indices based on the fitting of curves to monthly ratios, expressed as percentages, to moving averages are called moving seasonal indexes.

ISAAC PAENSON

1970-01-01T23:59:59.000Z

282

How to Construct a Seasonal Index  

E-Print Network [OSTI]

For many crops, seasonality is often the dominant factor influencing prices within a single production period. This publication explains how to construct and use several kinds of seasonal indexes for crop marketing information....

Tierney Jr., William I.; Waller, Mark L.; Amosson, Stephen H.

1999-07-12T23:59:59.000Z

283

Characteristics of fluid flow and heat transfer in a fluidized heat exchanger with circulating solid particles  

Science Journals Connector (OSTI)

The commercial viability of heat exchanger is mainly dependent on its long- ... loss and degrades the thermal performance of a heat exchanger. An experimental study was performed to investigate the characteristic...

Soo Whan Ahn; ByungChang Lee; WonCheol Kim; Myung- Whan Bae…

2002-09-01T23:59:59.000Z

284

Effect of refrigerant charge, duct leakage, and evaporator air flow on the high temerature performance of air conditioners and heat pumps.  

E-Print Network [OSTI]

??An experimental study was conducted to quantify the effect of several installation items on the high outdoor ambient temperature performance of air conditioners. These installation… (more)

Rodriguez, Angel Gerardo

2012-01-01T23:59:59.000Z

285

HEAT STORAGE AND ADVECTION IN THE NORTH PACIFIC OCEAN  

E-Print Network [OSTI]

HEAT STORAGE AND ADVECTION IN THE NORTH PACIFIC OCEAN A DISSERTATION SUBMITTED TO THE GRADUATE maintaining the seasonal heat storage in the 0 to 250 meter surface layer of the North Pacific Ocean. Approximately 140,000 bathy- thermograph observations taken in the Pacific Ocean from 10° South latitude to 70

Luther, Douglas S.

286

E-Print Network 3.0 - advanced heat transfer Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Performance Evaluations Alternate... and Diagnostic Center (EADC) Ground Coupled Heat Pumps Heat and Mass Transfer in Attic Systems Industrial... and Heat Transfer...

287

E-Print Network 3.0 - additional heating systems Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

HEAT ENGINE ANALYSIS Summary: on overall system performance. Along with the addition of a heat loss term to the surroundings, the general... -reversible heat engine model is...

288

Performance of a pressure-based unstructured code and a multi-block structured code for heat transfer and fluid flow  

Science Journals Connector (OSTI)

This paper reports a multi-block unstructured method for incompressible flows and the performance comparison with a multi-block structured method. The unstructured collocated grid is composed of arbitrary cell shapes. Pressure and velocity are stored at cell centres; Rhie and Chow interpolation is used to prevent checker boarding. The SIMPLE algorithm is used for pressureâ??velocity coupling. The code is calibrated with benchmark cases using hexahedral and prism meshes, and is shown to perform very well for all cases considered. In addition, the performances of the structured and unstructured codes are compared.

Rongguang Jia; Bengt Sunden

2005-01-01T23:59:59.000Z

289

Heat Stroke  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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 ■ High body temperature ■ Confusion ■ Loss of coordination ■ Hot, dry skin or profuse sweating ■ Throbbing headache ■ Seizures, coma First Aid ■ Request immediate medical assistance. ■ Move the worker to a cool, shaded area. ■ 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 ■ Rapid heart beat ■ Heavy sweating ■ Extreme weakness or fatigue ■

290

Natural Gas Heat Pump and Air Conditioner | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Natural Gas Heat Pump and Air Conditioner Natural Gas Heat Pump and Air Conditioner Lead Performer: Thermolift - Stony Brook, NY Partners: -- New York State Energy Research &...

291

Process Heating Assessment and Survey Tool Fact Sheet  

Broader source: Energy.gov [DOE]

This fact sheet describes how industrial plants can improve their process heating system performance using AMO's Process Heating Assessment and Survey Tool (PHAST)

292

Värmeöverföring i bergvärmesystem; Heat transfer in ground source heat pump systems.  

E-Print Network [OSTI]

?? The borehole heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of… (more)

Westin, Rasmus

2012-01-01T23:59:59.000Z

293

Effect of refrigerant charge, duct leakage, and evaporator air flow on the high temerature performance of air conditioners and heat pumps  

E-Print Network [OSTI]

An experimental study was conducted to quantify the effect of several installation items on the high outdoor ambient temperature performance of air conditioners. These installation items were: improper amount of refrigerant charge, reduced...

Rodriguez, Angel Gerardo

2012-06-07T23:59:59.000Z

294

Influence of steam injection and hot gas bypass on the performance and operation of a combined heat and power system using a recuperative cycle gas turbine  

Science Journals Connector (OSTI)

The influence of steam injection and hot gas bypass on the performance and operation of ... power (CHP) system using a recuperative cycle gas turbine was investigated. A full off-design analysis ... in steam gene...

Soo Young Kang; Jeong Ho Kim; Tong Seop Kim

2013-08-01T23:59:59.000Z

295

Influence of steam injection through exhaust heat recovery on the design performance of solid oxide fuel cell — gas turbine hybrid systems  

Science Journals Connector (OSTI)

This study analyzed the influence of steam injection on the performance of hybrid systems combining a solid oxide fuel cell and a gas turbine. Two different ... the effects of injecting steam, generated by recovering

Sung Ku Park; Tong Seop Kim; Jeong L. Sohn

2009-02-01T23:59:59.000Z

296

Atmospheric Environment 39 (2005) 39673976 Seasonal trends in PM2.5 source contributions in  

E-Print Network [OSTI]

as dust (20%), secondary sulfate (17%), secondary nitrate (10%), coal combustion (7%), diesel and gasoline heating season, the contributions from coal combustion and biomass aerosol to PM2.5 mass increased of Technology, Pasadena, CA 91125, USA c Environmental Chemistry and Technology Program, University of Wisconsin

Zheng, Mei

297

Seasonal variation of upwelling in the Alaskan Beaufort Sea: Impact of sea ice cover  

E-Print Network [OSTI]

that lateral ocean heat flux from the shelf to the basin melts a substantial amount of ice in the marginal iceSeasonal variation of upwelling in the Alaskan Beaufort Sea: Impact of sea ice cover Lena M to characterize differences in upwelling near the shelf break in the Alaskan Beaufort Sea due to varying sea ice

Pickart, Robert S.

298

Seasonal variation of upwelling in the Alaskan Beaufort Sea: Impact of sea ice cover  

E-Print Network [OSTI]

ocean heat flux42 from the shelf to the basin melts a substantial amount of ice in the marginal ice Seasonal variation of upwelling in the Alaskan Beaufort Sea: Impact of sea ice cover Lena M the shelfbreak in the Alaskan Beaufort Sea due to3 varying sea-ice conditions. The record is divided into three

Pickart, Robert S.

299

Seasonal contrast in the surface energy balance of the Sahel R. L. Miller,1,2  

E-Print Network [OSTI]

Africa, soil moisture is often so depleted that solar heating is balanced mainly by longwave radiationSeasonal contrast in the surface energy balance of the Sahel R. L. Miller,1,2 A. Slingo,3,4 J. C (AMF) in Niamey, Niger, evaporation makes a significant contribution to the surface energy balance only

300

Reduce Your Heating Bills with Better Insulation | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Reduce Your Heating Bills with Better Insulation Reduce Your Heating Bills with Better Insulation Reduce Your Heating Bills with Better Insulation October 3, 2008 - 11:09am Addthis John Lippert If you pay your own energy bills, you don't need to be reminded that energy prices are escalating. Energy price projections for this coming winter are not encouraging. According to the Energy Information Administration, residential natural gas prices during the upcoming heating season (October though March) are projected to average $14.93 per Mcf, an increase of about 17% compared to last year's heating season. Residential heating oil prices are projected to average $4.13 per gallon this winter, an increase of about 25%. What if you live in an all-electric house? Many utilities are continuing to pursue retail electricity rate increases in response to power generation

Note: This page contains sample records for the topic "heating season performance" 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

Reduce Your Heating Bills with Better Insulation | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Reduce Your Heating Bills with Better Insulation Reduce Your Heating Bills with Better Insulation Reduce Your Heating Bills with Better Insulation October 3, 2008 - 11:09am Addthis John Lippert If you pay your own energy bills, you don't need to be reminded that energy prices are escalating. Energy price projections for this coming winter are not encouraging. According to the Energy Information Administration, residential natural gas prices during the upcoming heating season (October though March) are projected to average $14.93 per Mcf, an increase of about 17% compared to last year's heating season. Residential heating oil prices are projected to average $4.13 per gallon this winter, an increase of about 25%. What if you live in an all-electric house? Many utilities are continuing to pursue retail electricity rate increases in response to power generation

302

Heating Oil and Propane Update  

Gasoline and Diesel Fuel Update (EIA)

SHOPP Financial Forms - for State Energy Officials SHOPP Financial Forms - for State Energy Officials The Federal forms below are required for State Energy Officials participating in the State Heating Oil and Propane Program (SHOPP) to execute their cooperative agreements with the U. S. Energy Information Administration. The Application for Federal Assistance, Form SF-424, is required to be submitted annually no later than May 15th in order for the applicant to receive funds for the upcoming season. This form consists of three parts: SF-424 - general funding information SF-424A - annual budget SF-424B - assurance pages The Federal Financial Report, Form SF-425, collects basic data on federal and recipient expenditures related to the SHOPP grant. This form should be submitted by August 1st of each year after the end of the season.

303

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

304

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

305

Design, development and testing of a solar-powered multi-family residential size prototype turbocompressor heat pump  

SciTech Connect (OSTI)

A program described to design, fabricate, and conduct preliminary testing of a prototype solar-powered Rankine cycle turbocompressor heat pump module for a multi-family residential building is presented. A solar system designed to use the turbocompressor heat pump module including all of the subsystems required and the various system operating modes is described in Section I. Section II includes the preliminary design analyses conducted to select the heat pump module components and operating features, working fluid, configuration, size and performance goals, and estimated performance levels in the cooling and heating modes. Section III provides a detailed description of the other subsystems and components required for a complete solar installation. Using realistic performance and cost characteristics for all subsystems, the seasonal performance of the UTC heat pump is described in various US locations. In addition, the estimated energy savings and an assessment of the economic viability of the solar system is presented in Section III. The detailed design of the heat pump module and the arrangement of components and controls selected to conduct the laboratory performance tests are described in Section IV. Section V provides a description of the special laboratory test facility, including the subsystems to simulate the collectors and storage tanks for building load and ambient conditions and the instrumentation, monitoring, and data acquisition equipment. The test results and sample computer analyses and comparisons with predicted performance levels are presented in Section VI. Various appendices provide supplementary and background information concerning working fluid selection (A), configuration selection (B), capacity control concepts (C), building models (D), computer programs used to determine component and system performance and total system economics (E), and weather data (F).

None

1981-03-01T23:59:59.000Z

306

Heat Transfer Research, 2010, Vol. 41, No. 6 Turbine Aero-Heat Transfer Studies  

E-Print Network [OSTI]

AU TH O R PR O O F Heat Transfer Research, 2010, Vol. 41, No. 6 Turbine Aero-Heat Transfer Studies in Rotating Research Facilities CENGIZ CAMCI Turbomachinery Aero-Heat Transfer Laboratory, Department The present paper deals with the experimental aero-heat transfer studies performed in rotating turbine

Camci, Cengiz

307

Field Measurements of Heating System Efficiency in Nine Electrically-Heated Manufactured Homes.  

SciTech Connect (OSTI)

This report presents the results of field measurements of heating efficiency performed on nine manufactured homes sited in the Pacific Northwest. The testing procedure collects real-time data on heating system energy use and heating zone temperatures, allowing direct calculation of heating system efficiency.

Davis, Bob; Siegel, J.; Palmiter, L.; Baylon, D.

1996-07-01T23:59:59.000Z

308

Intrinsically irreversible heat engine  

DOE Patents [OSTI]

A class of heat engines based on an intrinsically irreversible heat transfer process is disclosed. In a typical embodiment the engine comprises a compressible fluid that is cyclically compressed and expanded while at the same time being driven in reciprocal motion by a positive displacement drive means. A second thermodynamic medium is maintained in imperfect thermal contact with the fluid and bears a broken thermodynamic symmetry with respect to the fluid. The second thermodynamic medium is a structure adapted to have a low fluid flow impedance with respect to the compressible fluid, and which is further adapted to be in only moderate thermal contact with the fluid. In operation, thermal energy is pumped along the second medium due to a phase lag between the cyclical heating and cooling of the fluid and the resulting heat conduction between the fluid and the medium. In a preferred embodiment the engine comprises an acoustical drive and a housing containing a gas which is driven at a resonant frequency so as to be maintained in a standing wave. Operation of the engine at acoustic frequencies improves the power density and coefficient of performance. The second thermodynamic medium can be coupled to suitable heat exchangers to utilize the engine as a simple refrigeration device having no mechanical moving parts. Alternatively, the engine is reversible in function so as to be utilizable as a prime mover by coupling it to suitable sources and sinks of heat.

Wheatley, J.C.; Swift, G.W.; Migliori, A.

1984-01-01T23:59:59.000Z

309

New test methodologies to analyse direct expansion solar assisted heat pumps for domestic hot water  

Science Journals Connector (OSTI)

Abstract Since there are not specific standards for testing direct expansion solar assisted heat pumps for domestic hot water, new testing methodologies are proposed supported by laboratory experiments. Two methodologies were developed for performance measurement: modified BIN method and long term performance prediction with a TRNSYS model validated with specific experimental conditions. The long term performance prediction is a methodology similar to the already obtained for solar thermal systems. A system was tested in Lisbon during one year, covering almost all possible local weather conditions. The hot water tapping test cycle used was in agreement with recent standards EN16147:2011 or EN15316-3-1:2007. The influence of average daily air temperature, dew point temperature and solar irradiation was analysed. The seasonal performance factor was calculated for two cities in Portugal (Lisbon and Porto) and for additional four cities in Europe (Davos, Athens, Helsinki and Strasburg). The establishment of a procedure to calculate the seasonal performance of this kind of systems is very important according to the directive 2009/28/EC of the European Parliament and of the Council.

Jorge Facão; Maria João Carvalho

2014-01-01T23:59:59.000Z

310

The economics of heat mining: An analysis of design options and performance requirements of hot dry rock (HDR) geothermal power systems  

SciTech Connect (OSTI)

A generalized economic model was developed to predict the breakeven price of HDR generated electricity. Important parameters include: (1) resource quality--average geothermal gradient ({sup o}C/km) and well depth, (2) reservoir performance--effective productivity, flow impedance, and lifetime (thermal drawdown rate), (3) cost components--drilling, reservoir formation, and power plant costs and (4) economic factors--discount and interest rates, taxes, etc. Detailed cost correlations based on historical data and results of other studies are presented for drilling, stimulation, and power plant costs. Results of the generalized model are compared to the results of several published economic assessments. Critical parameters affecting economic viability are drilling costs and reservoir performance. For example, high gradient areas are attractive because shallower well depths and/or lower reservoir production rates are permissible. Under a reasonable set of assumptions regarding reservoir impedance, accessible rock volumes and surface areas, and mass flow rates (to limit thermal drawdown rates to about 10 C per year), predictions for HDR-produced electricity result in competitive breakeven prices in the range of 5 to 9 cents/kWh for resources having average gradients above 50 C/km. Lower gradient areas require improved reservoir performance and/or lower well drilling costs.

Tester, Jefferson W.; Herzog, Howard J.

1991-01-25T23:59:59.000Z

311

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...

Ganapathy, V.

312

Heating System Specification Specification of Heating System  

E-Print Network [OSTI]

Appendix A Heating System Specification /* Specification of Heating System (loosely based */ requestHeat : Room ­? bool; 306 #12; APPENDIX A. HEATING SYSTEM SPECIFICATION 307 /* user inputs */ livingPattern : Room ­? behaviour; setTemp : Room ­? num; heatSwitchOn, heatSwitchOff, userReset : simple

Day, Nancy

313

Thermal monitoring and optimization of geothermal district heating systems using artificial neural network: A case study  

Science Journals Connector (OSTI)

This paper deals with determine the energy and exergy efficiencies and exergy destructions for thermal optimization of a geothermal district heating system by using artificial neural network (ANN) technique. As a comprehensive case study, the Afyonkarahisar geothermal district heating system (AGDHS) in Afyonkarahisar/Turkey is considered and its actual thermal data as of average weekly data are collected in heating seasons during the period 2006–2010 for ANN based monitoring and thermal optimization. The measured data and calculated values are used at the design of Levenberg-Marquardt (LM) based multi-layer perceptron (MLP) in Matlab program. The results of the study are described graphically. The results show that the developed model is found to quickly predict the thermal performance and exergy destructions of the AGDHS with good accuracy. In addition, two main factors play important roles in the thermal optimization: (i) ambient temperature and (ii) flow rates in energy distribution cycle of the AGDHS. Various cases are investigated to determine how to change the energy and exergy efficiencies of the AGDHS for the temperature and flow rate. Finally, a monitoring and performance evaluation of a geothermal district heating system and its components by ANN will reduce the losses and human involvement and make the system more effective and efficient.

Ali Keçeba?; ?smail Yabanova

2012-01-01T23:59:59.000Z

314

Warm Winters Held Heating Oil Demand Down While Diesel Grew  

Gasoline and Diesel Fuel Update (EIA)

8 8 Notes: To understand the inventory situation, we must look the balance between demand and supply that drives inventories up or down. First consider demand. Most of the remaining charts deal with total distillate demand. Total distillate demand includes both diesel and heating oil. These are similar products physically, and prior to the low sulfur requirements for on-road diesel fuel, were used interchangeably. But even today, low sulfur diesel can be used in the heating oil market, but low sulfur requirements keep heating oil from being used in the on-road transportation sector. The seasonal increases and decreases in stocks stem from the seasonal demand in heating oil shown as the bottom red line. Heating oil demand increases by more than 50 percent from its low point to its high

315

heat pump | OpenEI  

Open Energy Info (EERE)

heat pump heat pump Dataset Summary Description View 2010 energy efficiency data from AeroSys Inc, Coaire, Cold Point, First Operations, LG Electronics, Nordyne, and Quietside manufacturers. Data includes cooling capacity, cooling performance, heating capacity, and heating performance. Spreadsheet was created by combining the tables in pdf files that are included in the zip file. Source Energy Applicance Data - United States Federal Trade Commission, www.ftc.gov Date Released Unknown Date Updated Unknown Keywords air conditioner central air conditioner efficiency efficient energy heat pump Data application/vnd.ms-excel icon 2010_CentralAC_All.xls (xls, 82.4 KiB) application/zip icon 2010CentralAirConditioner.zip (zip, 398.2 KiB) Quality Metrics Level of Review Some Review

316

Minimal universal quantum heat machine  

E-Print Network [OSTI]

In traditional thermodynamics the Carnot cycle yields the ideal performance bound of heat engines and refrigerators. We propose and analyze a minimal model of a heat machine that can play a similar role in quantum regimes. The minimal model consists of a single two-level system with periodically modulated energy splitting that is permanently, weakly, coupled to two spectrally-separated heat baths at different temperatures. The equation of motion allows to compute the stationary power and heat currents in the machine consistently with the second-law of thermodynamics. This dual-purpose machine can act as either an engine or a refrigerator (heat pump) depending on the modulation rate. In both modes of operation the maximal Carnot efficiency is reached at zero power. We study the conditions for finite-time optimal performance for several variants of the model. Possible realizations of the model are discussed.

David Gelbwaser-Klimovsky; Robert Alicki; Gershon Kurizki

2012-09-06T23:59:59.000Z

317

FEMP--Solar Water Heating  

Broader source: Energy.gov (indexed) [DOE]

More than 1 million homeowners and 200,000 busi- More than 1 million homeowners and 200,000 busi- nesses in the United States are using the sun to heat domestic water efficiently in almost any climate. In summer, a solar system properly sized for a resi- dential building can meet 100% of the building's water-heating needs in most parts of the country. In winter, the system might meet only half of this need, so another source of heat is used to back up the solar system. In either case, solar water heating helps to save energy, reduce utility costs, and preserve the environment. A solar water-heating system's performance depends primarily on the outdoor temperature, the temperature to which the water is heated, and the amount of sunlight striking the collector-the device that actually captures the sun's energy.

318

Optimized design of a heat exchanger for an air-to-water reversible heat pump working with propane (R290)  

E-Print Network [OSTI]

Optimized design of a heat exchanger for an air-to-water reversible heat pump working with propane-to-water reversible heat pump unit was carried out using two different fin-and-tube heat exchanger ``coil'' designs concepts. The performance of the heat pump was evaluated for each coil design at different superheat

Fernández de Córdoba, Pedro

319

Influenza Seasonality: Underlying Causes and Modeling Theories  

Science Journals Connector (OSTI)

...sporadic localized outbreaks. Such cases...mathematical models (31, 68...climates, flu infections...epidemics and outbreaks occur in tropical...seasonality. Flu season is characterized...dissemination model poses intriguing...accurately predict the incidence...respiratory syndrome outbreak at the Amoy...

Eric Lofgren; N. H. Fefferman; Y. N. Naumov; J. Gorski; E. N. Naumova

2006-12-20T23:59:59.000Z

320

Natural Refrigerant (R-729) Heat Pump  

Energy Savers [EERE]

Manufactured in the U.S. 2 Problem Statement * Current commercial and industrial heat pumps - Poor coefficient of performance (COP) at low temperatures * HFC refrigerant...

Note: This page contains sample records for the topic "heating season performance" 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

Home Heating Hints | Department of Energy  

Energy Savers [EERE]

Energy What are the key facts? Programmable thermostats, performing an air leak test, and removing blockages from heating registers can save you money and energy this...

322

Heating Oil and Propane Update  

Gasoline and Diesel Fuel Update (EIA)

Holiday Release Schedule Holiday Release Schedule The Heating Oil and Propane Update is produced during the winter heating season, which extends from October through March of each year. The standard release time and day of the week will be at 1:00 p. m. (Eastern time) on Wednesdays with the following exceptions. All times are Eastern. Data for: Alternate Release Date Release Day Release Time Holiday October 14, 2013 October 17, 2013 Thursday Cancelled Columbus/EIA Closed November 11, 2013 November 14, 2013 Thursday 1:00 p.m. Veterans December 23, 2013 December 27, 2013 Friday 1:00 p.m. Christmas December 30, 2013 January 3, 2014 Friday 1:00 p.m. New Year's January 20, 2014 January 23, 2014 Thursday 1:00 p.m. Martin Luther King Jr. February 17, 2014 February 20, 2014 Thursday 1:00 p.m. President's

323

Residential Slab-On-Grade Heat Transfer in Hot Humid Climates  

E-Print Network [OSTI]

Heat transfer through an uninsulated slab on grade is calculated using a simple method developed by Kusuda. The seasonal and annual slab loads are graphed as a function of annual average soil temperature, Tm, for a variety of floor system...

Clark, E.; Ascolese, M.; Collins, W.

1989-01-01T23:59:59.000Z

324

Impact of Ducting on Heat Pump Water Heater Space Conditioning Energy Use and Comfort  

SciTech Connect (OSTI)

Increasing penetration of heat pump water heaters (HPWHs) in the residential sector will offer an important opportunity for energy savings, with a theoretical energy savings of up to 63% per water heater and up to 11% of residential energy use (EIA 2009). However, significant barriers must be overcome before this technology will reach widespread adoption in the Pacific Northwest region and nationwide. One significant barrier noted by the Northwest Energy Efficiency Alliance (NEEA) is the possible interaction with the homes’ space conditioning system for units installed in conditioned spaces. Such complex interactions may decrease the magnitude of whole-house savings available from HPWH installed in the conditioned space in cold climates and could lead to comfort concerns (Larson et al. 2011; Kresta 2012). Modeling studies indicate that the installation location of HPWHs can significantly impact their performance and the resultant whole-house energy savings (Larson et al. 2012; Maguire et al. 2013). However, field data are not currently available to validate these results. This field evaluation of two GE GeoSpring HPWHs in the PNNL Lab Homes is designed to measure the performance and impact on the Lab Home HVAC system of a GE GeoSpring HPWH configured with exhaust ducting compared to an unducted GeoSpring HPWH during heating and cooling season periods; and measure the performance and impact on the Lab Home HVAC system of the GeoSpring HPWH with both supply and exhaust air ducting as compared to an unducted GeoSpring HPWH during heating and cooling season periods. Important metrics evaluated in these experiments include water heater energy use, HVAC energy use, whole house energy use, interior temperatures (as a proxy for thermal comfort), and cost impacts. This technical report presents results from the PNNL Lab Homes experiment.

Widder, Sarah H.; Petersen, Joseph M.; Parker, Graham B.; Baechler, Michael C.

2014-07-21T23:59:59.000Z

325

Numerical-simulation and experimental-validation of the largest Egyptian solar process-heat system  

Science Journals Connector (OSTI)

El-Nasr pharmaceutical solar process heat project is considered as the largest industrial system installed and working in east Cairo Egypt 30°N. It was simply constructed from a one-axis tracking parabolic-trough collector that can produce about 1.3 ton/h saturated steam to feed the industrial processes in the company. Twenty-three bar compressed water is heated inside 1958.4 m2 collectors and later on it is flashed in a steam flash-drum to produce saturated steam at 8 bars and 175 °C that is fed to the process heat. A mathematical model was developed for the system components to simulate annual performance of the system. The simulation results were verified successfully by the measured data that are monitoring the system performance. First each component of the mathematical model was experimentally validated separately. Accordingly the whole mathematical model was validated under different weather conditions along the year. The validated numerical model was optimized. The optimal number of collectors connected in series was obtained as three collectors not 36 as installed. An economical study of the installed system was provided. The optimal design of the system was economically estimated. The optimal collector area is less than that installed it equals about 538 m2. Annual performance of the system is presented indicating the seasonal variation. It was found that the optimized system can produce about 2 ton/h in average. Moreover that value is more than that was proposed by the system design.

Adel M. Abdel-Dayem

2011-01-01T23:59:59.000Z

326

Heat Pump Market in Thailand  

Science Journals Connector (OSTI)

The value of hot water system in Thailand, rarely mentioned or quantified, is almost 3,000 million Baht per year. The heat pump is an option of hot water system. The development of heat pump in Thailand is officially started in 2002 according to the program of subsidy for heat pump but before that there was some slow development. Comparing to the cost of hot water production from instantaneous system, local manufactured heat pump is commercial viable even without the subsidy. The imported heat pump compared to local production can be sold to only high end user or high awareness of energy. The important factor of heat pump development is depended on the selling price, performance, and the customer behavior. The highest efficiency may not be the winner in Thai market as the drivers for higher efficiency or co-efficiency of performance of heat pump is not so strong compared to the price. Some of information in this paper cannot be supported by the real data because of the brand name of heat pump cannot be published.

Kuaanan Techato

2012-01-01T23:59:59.000Z

327

Air-To-Water Heat Pumps with Radiant Delivery in Low Load Homes: Tucson, Arizona and Chico, California (Fact Sheet)  

SciTech Connect (OSTI)

Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 to test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).

Not Available

2013-11-01T23:59:59.000Z

328

Process Heating Assessment and Survey Tool  

Broader source: Energy.gov [DOE]

The Process Heating Assessment and Survey Tool (PHAST) introduces methods to improve thermal efficiency of heating equipment. This tool helps industrial users survey process heating equipment that consumes fuel, steam, or electricity, and identifies the most energy-intensive equipment. The tool can be used to perform a heat balance that identifies major areas of energy use under various operating conditions and test "what-if" scenarios for various options to reduce energy use.

329

Geothermal district heating systems  

SciTech Connect (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

330

U.S. Residential Heating Oil Prices  

Gasoline and Diesel Fuel Update (EIA)

5 5 Notes: 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 for the last four winters, with this year’s prices shown through January 24, 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 heating season is typically about 10 cents per gallon. Exceptions occur in unusual circumstances, such as very cold weather, large changes in crude oil prices, or supply problems. Although heating oil prices for consumers started this winter at similar levels to those in 1997, they already rose nearly 20 cents per gallon through mid-January. With the continuing upward pressure from crude

331

Winter Fuels Season is Right Around the Corner | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Winter Fuels Season is Right Around the Corner Winter Fuels Season is Right Around the Corner Winter Fuels Season is Right Around the Corner October 20, 2010 - 10:31am Addthis Patricia A. Hoffman Patricia A. Hoffman Assistant Secretary, Office of Electricity Delivery & Energy Reliability As temperatures start to drop Americans around the country are pulling out their flannel sheets, putting the storm windows back on, and switching their air conditioning units with heaters. These transformations have an impact on the way our nation uses our energy resources, particularly heating fuels. Since 1994, the U.S. Department of Energy and the National Association of State Energy Officials (NASEO) have held an annual Winter Fuels Outlook Conference to provide the energy community with information on global and

332

Winter Fuels Season is Right Around the Corner | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Winter Fuels Season is Right Around the Corner Winter Fuels Season is Right Around the Corner Winter Fuels Season is Right Around the Corner October 20, 2010 - 10:31am Addthis Patricia A. Hoffman Patricia A. Hoffman Assistant Secretary, Office of Electricity Delivery & Energy Reliability As temperatures start to drop Americans around the country are pulling out their flannel sheets, putting the storm windows back on, and switching their air conditioning units with heaters. These transformations have an impact on the way our nation uses our energy resources, particularly heating fuels. Since 1994, the U.S. Department of Energy and the National Association of State Energy Officials (NASEO) have held an annual Winter Fuels Outlook Conference to provide the energy community with information on global and

333

MAS 10.3 Seasonal Preparation 3/21/95 | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

3 Seasonal Preparation 3/21/95 3 Seasonal Preparation 3/21/95 MAS 10.3 Seasonal Preparation 3/21/95 The objective of this surveillance is to verify that the contractor is implementing appropriate measures to protect equipment and systems from damage due to the effects of cold weather. The Facility Representative evaluates systems necessary for the protection of the public and workers to determine if they have been adequately prepared for cold weather. The Facility Representative also examines other preparations for cold weather to ensure that materials are properly stored, permanent and auxiliary heating systems are functional, and other appropriate preparations have been completed. During the surveillance, the Facility Representative ensures that applicable DOE requirements have been implemented.

334

Microsoft Word - S08364_SeasonalVariation  

Office of Legacy Management (LM)

Groundwater Groundwater Constituents and Seasonal Variation at the Riverton, Wyoming, Processing Site February 2012 LMS/RVT/S08364 This page intentionally left blank U.S. Department of Energy Evaluation of Groundwater Constituents and Seasonal Variation, Riverton, Wyoming February 2012 Doc. No. S08364 Page 1 Evaluation of Groundwater Constituents and Seasonal Variation at the Riverton, Wyoming, Processing Site Executive Summary Historical groundwater monitoring at the Riverton site included collecting samples for a variety of analyses, including general water quality, inorganics, metals, and radionuclides. Evaluations of these constituents were conducted and presented in past documents, which resulted in four constituents of concern (COCs). This paper presents a reevaluation of 47 constituents using

335

Experimental study of a photovoltaic solar-assisted heat-pump/heat-pipe system  

Science Journals Connector (OSTI)

A practical design for a heat pump with heat-pipe photovoltaic/thermal (PV/T) collectors is presented. The hybrid system is called the photovoltaic solar-assisted heat-pump/heat-pipe (PV-SAHP/HP) system. To focus on both actual demand and energy savings, the PV-SAHP/HP system was designed to be capable of operating in three different modes, namely, the heat-pipe, solar-assisted heat pump, and air-source heat-pump modes. Based on solar radiation, the system operates in an optimal mode. A series of experiments were conducted in Hong Kong to study the performance of the system when operating in the heat-pipe and the solar-assisted heat-pump modes. Moreover, energy and exergy analyses were used to investigate the total PV/T performance of the system.

H.D. Fu; G. Pei; J. Ji; H. Long; T. Zhang; T.T. Chow

2012-01-01T23:59:59.000Z

336

Heat Pump Water Heating Modeling in EnergyPlus  

Broader source: Energy.gov (indexed) [DOE]

Heat Pump Water Heater Modeling Heat Pump Water Heater Modeling in EnergyPlus Building America Residential Energy Efficiency Stakeholder Meeting Eric Wilson Craig Christensen March 1, 2012 2 Modeling Issues Results Motivation Heat Pump Water Heater Modeling... 3 Gap: Existing analysis tools cannot accurately model HPWHs with reasonable runtime. 4 What have we achieved so far? Laboratory Evaluations 14 x Field Monitoring 5 Closing the Gap Laboratory Evaluations 6 sec timestep hourly timestep 14 x Field Monitoring CARB 6 Why is modeling important? * Performance varies: Can't just use EF * System interaction o HPWH affects building heating and cooling o Space conditions affect HPWH performance 7 Modeling Goals * Manage Risks o Accuracy o Run time o Occupant satisfaction * Flexibility to explore the effects of:

337

On the Seasonality of the Hadley Cell  

Science Journals Connector (OSTI)

The annual march of the climatological mean meridional circulations (MMCs) in the NCEP–NCAR reanalyses is dominated by two components of roughly comparable mean-squared amplitude: 1) a seasonally invariant pair of “Hadley cells” with rising ...

Ioana M. Dima; John M. Wallace

2003-06-01T23:59:59.000Z

338

Product Price Spreads Over Crude Oil Vary With Seasons and Supply/Demand  

Gasoline and Diesel Fuel Update (EIA)

6 6 Notes: Of course, petroleum product prices don't move in lockstep to crude oil prices, for a number of reasons. We find it useful to look at variations in the spread between product and crude oil prices, in this case comparing spot market prices for each. The difference between heating oil and crude oil spot prices tends to vary seasonally; that is, it's generally higher in the winter, when demand for distillate fuels is higher due to heating requirements, and lower in the summer. (Gasoline, as we'll see later, generally does the opposite.) However, other factors affecting supply and demand, including the relative severity of winter weather, can greatly distort these "typical" seasonal trends. As seen on this chart, the winters of 1995-96 and 1996-97 featured

339

Seasonal snow of arctic Alaska R4D investigations. Final report  

SciTech Connect (OSTI)

Seasonal snow is present on the Arctic Slope of Alaska for nine months each year. Its presence or absence determines whether 80% of the solar radiation is reflected or absorbed, respectively. Although life on the Arctic Slope is adapted to, and in some cases dependent upon seasonal snow, little is known about it from a scientific point of view. Its quantity has been grossly underestimated, and knowledge of its distribution and the extent of wind transport and redistribution is very limited. This research project dealt with the amount, regional distribution and physical properties of wind blown snow and its biological role in the R4D area of the Arctic Slope. Physical processes which operate within the snow that were studied included the flux of heat and vapor and the fractionation of stable isotopes through it during fall and winter, and the complex heat and mass transfer within the snow and between snow, its substrate and the overlying atmosphere during the melt period.

Benson, C.S.

1993-02-01T23:59:59.000Z

340

Heat transfer and heat exchangers reference handbook  

SciTech Connect (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

Note: This page contains sample records for the topic "heating season performance" 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

Heating systems for heating subsurface formations  

DOE Patents [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

342

Artificial neural network modeling of geothermal district heating system thought exergy analysis  

Science Journals Connector (OSTI)

This paper deals with an artificial neural network (ANN) modeling to predict the exergy efficiency of geothermal district heating system under a broad range of operating conditions. As a case study, the Afyonkarahisar geothermal district heating system (AGDHS) in Turkey is considered. The average daily actual thermal data acquired from the AGDHS in the 2009–2010 heating season are collected and employed for exergy analysis. An ANN modeling is developed based on backpropagation learning algorithm for predicting the exergy efficiency of the system according to parameters of the system, namely the ambient temperature, flow rate and well head temperature. Then, the recorded and calculated data conducted in the AGDHS at different dates are used for training the network. The results showed that the network yields a maximum correlation coefficient with minimum coefficient of variance and root mean square values. The results confirmed that the ANN modeling can be applied successfully and can provide high accuracy and reliability for predicting the exergy performance of geothermal district heating systems.

Ali Keçeba?; ?smail Yabanova; Mehmet Yumurtac?

2012-01-01T23:59:59.000Z

343

Heat exchanger optimization for geothermal district heating systems: A fuel saving approach  

Science Journals Connector (OSTI)

One of the most commonly used heating devices in geothermal systems is the heat exchanger. The output conditions of heat exchangers are based on several parameters. The heat transfer area is one of the most important parameters for heat exchangers in terms of economics. Although there are a lot of methods to optimize heat exchangers, the method described here is a fairly easy approach. In this paper, a counter flow heat exchanger of geothermal district heating system is considered and optimum design values, which provide maximum annual net profit, for the considered heating system are found according to fuel savings. Performance of the heat exchanger is also calculated. In the analysis, since some values are affected by local conditions, Turkey's conditions are considered.

Ahmet Dagdas

2007-01-01T23:59:59.000Z

344

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

345

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, P.J.

1983-12-08T23:59:59.000Z

346

Absorption Heat Pump Water Heater  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Absorption Heat Pump Water Heater Absorption Heat Pump Water Heater Kyle Gluesenkamp Building Equipment Group, ETSD gluesenkampk@ornl.gov 865-241-2952 April 3, 2013 CRADA - GE Development of High Performance Residential Gas Water Heater Image courtesy John Wilkes 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: Absorption technology could greatly boost water heater efficiency, but faces barriers of high first cost and working fluid challenges. Impact of Project: Energy factor of gas storage water

347

Absorption Heat Pump Water Heater  

Broader source: Energy.gov (indexed) [DOE]

Absorption Heat Pump Water Heater Absorption Heat Pump Water Heater Kyle Gluesenkamp Building Equipment Group, ETSD gluesenkampk@ornl.gov 865-241-2952 April 3, 2013 CRADA - GE Development of High Performance Residential Gas Water Heater Image courtesy John Wilkes 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: Absorption technology could greatly boost water heater efficiency, but faces barriers of high first cost and working fluid challenges. Impact of Project: Energy factor of gas storage water

348

Low-Cost Gas Heat Pump For Building Space Heating | Department...  

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

Space Heating Lead Performer: Stone Mountain Technologies - Erwin, TN Partners: -- A.O. Smith - Milwaukee, WI -- Gas Technology Institute - Des Plaines, IL DOE Funding: 903,000...

349

Thermochemical process for seasonal storage of solar energy: characterization and modeling of a high-density reactive bed  

E-Print Network [OSTI]

1 Thermochemical process for seasonal storage of solar energy: characterization and modeling to maximize the use of solar energy for house heating, it is interesting to valorize the solar energy excess efficiency, and a 20 per cent share of renewable). The use of renewable energies and in particular solar

Paris-Sud XI, Université de

350

Heat Pump Water Heater Performance in  

Broader source: Energy.gov [DOE]

This presentation was delivered at the U.S. Department of Energy Building America Technical Update meeting on April 29-30, 2013, in Denver, Colorado.

351

Optimizing performance of energy systems  

SciTech Connect (OSTI)

This book discusses optimizing performance of energy systems. Topics covered include a test station, heat flow integrator, microcomputer control of MIMIC operation, and microcomputer control of simulation operation.

Stricker, S.

1985-01-01T23:59:59.000Z

352

Geothermal heating retrofit at the Utah State Prison Minimum Security Facility. Final report, March 1979-January 1986  

SciTech Connect (OSTI)

This report is a summary of progress and results of the Utah State Prison Geothermal Space Heating Project. Initiated in 1978 by the Utah State Energy Office and developed with assistance from DOE's Division of Geothermal and Hydropower Technologies PON program, final construction was completed in 1984. The completed system provides space and water heating for the State Prison's Minimum Security Facility. It consists of an artesian flowing geothermal well, plate heat exchangers, and underground distribution pipeline that connects to the existing hydronic heating system in the State Prison's Minimum Security Facility. Geothermal water disposal consists of a gravity drain line carrying spent geothermal water to a cooling pond which discharges into the Jordan River, approximately one mile from the well site. The system has been in operation for two years with mixed results. Continuing operation and maintenance problems have reduced the expected seasonal operation from 9 months per year to 3 months. Problems with the Minimum Security heating system have reduced the expected energy contribution by approximately 60%. To date the system has saved the prison approximately $18,060. The total expenditure including resource assessment and development, design, construction, performance verification, and reporting is approximately $827,558.

Not Available

1986-01-01T23:59:59.000Z

353

ENERGY ABSORBER HEAT PUMP SYSTEM TO SUPPLEMENT HEAT RECOVERY SYSTEMS IN AN INDOOR SWIMMING POOL  

Science Journals Connector (OSTI)

ABSTRACT Compared with convontional indoor swimming pools with traditional plant engineering, the Schwalmtal indoor swimming pool has a final energy consumption of just 40%. This low consumption is achieved by improved insulation of the building's enveloping surface, through the operation of systems for the recovery of heat from drain water and waste air as well as by the operation of a heat pump system to gain ambient heat. The decentralised heat recovery systems met between 40 and 80% of the heat requirements in the supply areas where they were used. The electric heat pump system, which is operated in the bivalent mode in parallel to a heating boiler, could generate 75% of the heat provided by the central heating circuit to meet the residual heat requirements. The report illustrates the structure of the residual heat requirements of the central heating circuit. A description is given of the measured coefficients of performance of the brine/water heat pump connected by a brine circuit with two different energy absorber types - energy stack and energy roof. Finally, the ambient energy gained with the absorbers is broken down into the various kinds of heat gains from radiation, convection, condensation etc. KEYWORDS Energy absorber; energy stack; energy roof; heat pump; heat recovery systems; indoor swimming pool; energy engineering concept.

K. Leisen

1988-01-01T23:59:59.000Z

354

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

355

NOVA Making Stuff Season 2  

SciTech Connect (OSTI)

Over the course of four weeks in fall 2013, 11.7 million Americans tuned in to PBS to follow host David Pogue as he led them in search of engineering and scientific breakthroughs poised to change our world. Levitating trains, quantum computers, robotic bees, and bomb-detecting plants—these were just a few of the cutting-edge innovations brought into the living rooms of families across the country in NOVA’s four-part series, Making Stuff: Faster, Wilder, Colder, and Safer. Each of the four one-hour programs gave viewers a behind-the-scenes look at novel technologies poised to change our world—showing them how basic research and scientific discovery can hold the keys to transforming how we live. Making Stuff Season 2 (MS2) combined true entertainment with educational value, creating a popular and engaging series that brought accessible science into the homes of millions. NOVA’s goal to engage the public with such technological innovation and basic research extended beyond the broadcast series, including a variety of online, educational, and promotional activities: original online science reporting, web-only short-form videos, a new online quiz-game, social media engagement and promotion, an educational outreach “toolkit” for science educators to create their own “makerspaces,” an online community of practice, a series of nationwide Innovation Cafés, educator professional development, a suite of teacher resources, an “Idealab,” participation in national conferences, and specialized station relation and marketing. A summative evaluation of the MS2 project indicates that overall, these activities helped make a significant impact on the viewers, users, and participants that NOVA reached. The final evaluation conducted by Concord Evaluation Group (CEG) confidently concluded that the broadcast, website, and outreach activities were successful at achieving the project’s intended impacts. CEG reported that the MS2 series and website content were successful in raising awareness and sparking interest in innovation, and increased public awareness that basic research leads to technological innovation; this interest was also sustained over a six month period. Efforts to create an online community of practice were also successful: the quality of collaboration increased, and community members felt supported while using Maker pedagogy. These findings provide clear evidence that large-scale science media projects like MS2 are an effective means of “moving the needle” on attitudes about and excitement for science. NOVA’s broadcast audience and ratings have always indicated that a large portion of the population is interested in and engages with educational science media on a weekly basis. Yet these evaluation results provide the empirical evidence that beyond being capable of attracting, maintaining, and growing a dedicated group of citizens interested in science, these shows—with their diverse content provided on a variety of media channels—are capable of sparking new interest in science, raising public awareness of the importance of science, and maintaining and growing that interest over time. In a country where approximately a quarter of the population doesn’t know the earth rotates around the sun,1 roughly half still don’t accept evolution,2 and about 20% don’t think climate change is happening,3 the importance of these findings cannot be overstated. The success of MS2 suggests that large-scale media projects dedicated to and linked by coverage of scientific “big ideas” are an effective means of shifting public opinion on—and improving understanding of—science. REFERENCES 1, 2 National Science Foundation, Science and Engineering Indicators (2014). Chapter 7: Science and Technology: Public Attitudes and Understanding. 3 Leiserowitz, A., Maibach, E., Roser-Renouf, C., Feinberg, G., & Rosenthal, S. (2014) Climate change in the American mind: April, 2014. Yale University and George Mason University. New Haven, CT: Yale Project on Climate Change Communication.

Leombruni, Lisa; Paulsen, Christine Andrews

2014-12-12T23:59:59.000Z

356

Control and optimal operation of simple heat pump cycles  

E-Print Network [OSTI]

Control and optimal operation of simple heat pump cycles Jørgen Bauck Jensen and Sigurd Skogestad in the opposite direction, the "heat pump", has recently become pop- ular. These two applications have also merged. The coefficients of performance for a heating cycle (heat pump) and a cooling cycle (refrigerator, A/C) are defined

Skogestad, Sigurd

357

DEVELOPMENT OF THFEGENERAL ELECTRIC STIRLING ENGINE GAS HEAT PUMP  

E-Print Network [OSTI]

DEVELOPMENT OF THFEGENERAL ELECTRIC STIRLING ENGINE GAS HEAT PUMP R. C. Meier, Program Manager, Gas Heat Pump Program General Electric Company P. 0. Box 8555 Philadelphia, Pennsylvania 19101 FILE COPY DO NOT REMOVE SUMMARY The Stirling/Rankine Heat Activated Heat Pump is a high performance product for space

Oak Ridge National Laboratory

358

Nutritional Correlates of the "Lean Season": Effects of Seasonality and Frugivory on the  

E-Print Network [OSTI]

and energy intakes, though season had an independent effect. These results suggest that factors restricting, Bronx, NY 6 Department of Anthropology, Hunter College, City University of New York, New York, NY 7 New to understand 1) how macronutrient and energy intakes vary seasonally, including whether these intakes respond

Rothman, Jessica M.

359

Supercharger for Heat Pumps in Cold Climates  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Supercharger for Heat Supercharger for Heat Pumps in Cold Climates Thomas J. Walter Mechanical Solutions, Inc. tjw@mechsol.com 518-320-8552 April 3, 2013 DOE SBIR Grant No. SC0006162 Concept is similar to superchargers for piston engine aircraft 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: Electrically driven heat pumps are an effective method of extracting heat from ambient air. As air temperature falls, however, heat pump performance falls off, essentially limiting their year round usefulness to

360

Supercharger for Heat Pumps in Cold Climates  

Broader source: Energy.gov (indexed) [DOE]

Supercharger for Heat Supercharger for Heat Pumps in Cold Climates Thomas J. Walter Mechanical Solutions, Inc. tjw@mechsol.com 518-320-8552 April 3, 2013 DOE SBIR Grant No. SC0006162 Concept is similar to superchargers for piston engine aircraft 2 | Building Technologies Office eere.energy.gov Purpose & Objectives Problem Statement: Electrically driven heat pumps are an effective method of extracting heat from ambient air. As air temperature falls, however, heat pump performance falls off, essentially limiting their year round usefulness to

Note: This page contains sample records for the topic "heating season performance" 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

Cascade heat recovery with coproduct gas production  

DOE Patents [OSTI]

A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange. 4 figs.

Brown, W.R.; Cassano, A.A.; Dunbobbin, B.R.; Rao, P.; Erickson, D.C.

1986-10-14T23:59:59.000Z

362

7-117 The claim of a heat pump designer regarding the COP of the heat pump is to be evaluated. Assumptions The heat pump operates steadily.  

E-Print Network [OSTI]

7-47 7-117 The claim of a heat pump designer regarding the COP of the heat pump is to be evaluated. Assumptions The heat pump operates steadily. HP Wnet,in QH QL TL TH Analysis The maximum heat pump coefficient of performance would occur if the heat pump were completely reversible, 5.7 K026K300 K300 COP maxHP, LH H TT

Bahrami, Majid

363

Foundation heat exchangers for residential ground source heat pump systems Numerical modeling and experimental validation  

SciTech Connect (OSTI)

A new type of ground heat exchanger that utilizes the excavation often made for basements or foundations has been proposed as an alternative to conventional ground heat exchangers. This article describes a numerical model that can be used to size these foundation heat exchanger (FHX) systems. The numerical model is a two-dimensional finite-volume model that considers a wide variety of factors, such as soil freezing and evapotranspiration. The FHX numerical model is validated with one year of experimental data collected at an experimental house located near Oak Ridge, Tennessee. The model shows good agreement with the experimental data-heat pump entering fluid temperatures typically within 1 C (1.8 F) - with minor discrepancies due to approximations, such as constant moisture content throughout the year, uniform evapotranspiration over the seasons, and lack of ground shading in the model.

Xing, Lu [Oklahoma State University; Cullin, James [Oklahoma State University; Spitler, Jeffery [Oklahoma State University; Im, Piljae [ORNL; Fisher, Daniel [Oklahoma State University

2011-01-01T23:59:59.000Z

364

Test results of a Stirling engine utilizing heat exchanger modules with an integral heat pipe  

SciTech Connect (OSTI)

The Heat Pipe Stirling Engine (HP-1000), a free-piston Stirling engine incorporating three heat exchanger modules, each having a sodium filled heat pipe, has been tested at the NASA-Lewis Research Center as part of the Civil Space Technology Initiative (CSTI). The heat exchanger modules were designed to reduce the number of potential flow leak paths in the heat exchanger assembly and incorporate a heat pipe as the link between the heat source and the engine. An existing RE-1000 free-piston Stirling engine was modified to operate using the heat exchanger modules. This paper describes heat exchanger module and engine performance during baseline testing. Condenser temperature profiles, brake power, and efficiency are presented and discussed.

Skupinski, R.C.; Tower, L.K.; Madi, F.J.; Brusk, K.D.

1993-04-01T23:59:59.000Z

365

Heating Oil and Propane Update - Energy Information Administration  

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

all Petroleum Reports all Petroleum Reports Heating Oil and Propane Update Weekly heating oil and propane prices are only collected during the heating season, which extends from October through March. U.S. Heating Oil and Propane Prices Residential Heating Oil Graph. Residential Propane Graph. change from change from Heating Oil 12/16/2013 week ago year ago Propane 12/16/2013 week ago year ago Residential 3.952 values are down 0.004 values are down 0.008 Residential 2.712 values are up 0.091 values are up 0.469 Wholesale 3.074 values are down 0.063 values are not available NA Wholesale 1.637 values are up 0.113 values are not available NA Note: Price in dollars per gallon, excluding taxes. Values shown on the graph and corresponding data pages for the previous week may be revised to account for late submissions and corrections.

366

Hydroxide absorption heat pumps with spray absorber  

SciTech Connect (OSTI)

The absorber is one of the most expensive components of an absorption heat pump or chiller, respectively. In order to reduce the cost of a heat exchanger, much effort is invested into searching for additives for heat transfer enhancement. Another way to reduce heat exchanger cost, especially for machines with low capacities, is to use an adiabatic spray absorber. The basic principles of the spray absorber is to perform heat and mass transfer separated from each other in two different components. In this way the heat can be rejected effectively in a liquid-liquid heat exchanger, whereas the mass transfer occurs subsequently in a simple vessel. The spray technique can not only save heat exchanger cost in conventional absorption systems working with water and lithium bromide, it also allows the use of quite different working fluids such as hydroxides, which have lower heat transfer coefficients in falling films. Moreover, the separated heat transfer can easily be performed in a liquid-to-air heat exchanger. Hence it is obvious to use hydroxides that allow for a high temperature lift for building an air-cooled chiller with spray absorber. In this presentation theoretical and experimental investigations of the spray absorber as well as the setup will be described. Finally, possible applications will be outlined.

Summerer, F.; Alefeld, G. [Technische Univ. Muenchen, Munich (Germany). Physics Dept.; Zeigler, F.; Riesch, P. [Bayerisches Zentrum fuer Angewandte Energieforschung, Munich (Germany)

1996-11-01T23:59:59.000Z

367

Chapter 5 - Solar Water-Heating Systems  

Science Journals Connector (OSTI)

Abstract Chapter 5 is on solar water-heating systems. Both passive and active systems are described. Passive systems include thermosiphon and integrated collector storage systems. The former include theoretical performance of thermosiphon solar water heaters, reverse circulation in thermosiphon systems, vertical against horizontal tank configurations, freeze protection, and tracking thermosiphons. Subsequently, active systems are described, which include direct circulation systems, indirect water-heating systems, air water-heating systems, heat pump systems and pool heating systems, which include the analysis of various heat losses like evaporation, radiation, convection heat losses, make-up water load, and solar radiation-heat gain. Then the characteristics and thermal analysis of heat storage systems for both water and air systems are presented. The module and array design methods are then described and include the effects of shading, thermal expansion, galvanic corrosion, array sizing, heat exchangers, pipe and duct losses, partially shaded collectors and over-temperature protection—followed by an analysis of the characteristics of differential thermostats. Finally, methods to calculate the hot water demand are given as well as a review of international standards used to evaluate the solar water heaters performance. The chapter includes also simple system models and practical considerations for the setup of solar water-heating systems, which include: pipes, supports and insulation; pumps; valves and instrumentation.

Soteris A. Kalogirou

2014-01-01T23:59:59.000Z

368

An experimental study of waste heat recovery from a residential refrigerator  

SciTech Connect (OSTI)

This paper describes the design, construction, and testing of an integrated heat recovery system which has been designed both to enhance the performance of a residential refrigerator and simultaneously to provide preheated water for an electric hot water heater. A commercial, indirect-heated hot water tank was retrofitted with suitable tubing to permit it to serve as a water cooled condenser for a residential refrigerator. This condenser operates in parallel with the air-cooled condenser tubing of the refrigerator so that either one or the other is active when the refrigerator is running. The refrigerator was housed in a controlled-environment chamber, and it was instrumented so that its performance could be monitored carefully in conjunction with the water pre-heating system. The system has been tested under a variety of hot water usage protocols, and the resulting data set has provided significantly insight into issues associated with commercial implementation of the concept. For the case of no water usage, the system was able to provide a 35 C temperature rise in the storage tank after about 100 hours of continuous operation, with no detectable deterioration of the refrigerator performance. Preliminary tests with simulations of high water usage, low water usage, and family water usage indicate a possible 18--20% energy savings for hot water over a long period of operation. Although the economic viability for such a system in a residential environment would appear to be sub-marginal, the potential for such a system associated with commercial-scale refrigeration clearly warrants further study, particularly for climates for which air conditioning heat rejection is highly seasonal.

Clark, R.A.; Smith, R.N.; Jensen, M.K. [Rensselaer Polytechnic Inst., Troy, NY (United States)

1996-12-31T23:59:59.000Z

369

System Modeling of Gas Engine Driven Heat Pump  

SciTech Connect (OSTI)

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

2012-01-01T23:59:59.000Z

370

Floatable solar heat modules  

SciTech Connect (OSTI)

A floating solar heat module for swimming pools comprises a solid surface for conducting heat from the sun's rays to the water and further includes a solid heat storage member for continual heating even during the night. A float is included to maintain the solar heat module on the surface of the pool. The solid heat storage medium is a rolled metal disk which is sandwiched between top and bottom heat conducting plates, the top plate receiving the heat of the sun's rays through a transparent top panel and the bottom plate transferring the heat conducted through the top plate and rolled disk to the water.

Ricks, J.W.

1981-09-29T23:59:59.000Z

371

Analyzing the efficiency of a heat pump assisted drain water heat recovery system that uses a vertical inline heat exchanger  

Science Journals Connector (OSTI)

Abstract The purpose of the present study is to accumulate knowledge on how a drain water heat recovery system using a vertical inline heat exchanger and a heat pump performs under different drain water flow profile scenarios. Investigating how the intermittent behavior of the drain water influences the performance for this type of system is important because it gives insight on how the system will perform in a real life situation. The scenarios investigated are two 24 h drain water flow rate schedules and one shorter schedule representing a three minute shower. The results from the present paper add to the knowledge on how this type of heat recovery system performs in a setting similar to a multi-family building and how sizing influences the performance. The investigation shows that a heat recovery system of this type has the possibility to recover a large portion of the available heat if it has been sized to match the drain water profile. Sizing of the heat pump is important for the system performance; sizing of the storage tank is also important but not as critical.

Jörgen Wallin; Joachim Claesson

2014-01-01T23:59:59.000Z

372

Efficient Heat Engines and Heat Pumps (10 credits) The aim of the module is to introduce the various ideal thermodynamic cycles that form  

E-Print Network [OSTI]

Efficient Heat Engines and Heat Pumps (10 credits) The aim of the module is to introduce the various ideal thermodynamic cycles that form the basis for power generation, heat pumping and IC Engines performance. Syllabus Heat Engines and Heat Pumps · Second Law of Thermodynamics, Concept

Miall, Chris

373

Heat Pump for High School Heat Recovery  

E-Print Network [OSTI]

ICEBO2006, Shenzhen, China Renewable Energy Resources and a Greener Future Vol.VIII-12-1 Heat Pump for High School Bathroom Heat Recovery Kunrong Huang Hanqing Wang Xiangjiang Zhou Associate professor Professor Professor School...

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

2006-01-01T23:59:59.000Z

374

Fabric composite heat pipe technology development  

SciTech Connect (OSTI)

Testing has been performed on a variety of fabric composite technology feasibility issues. These include an evaluation of the effective radiation heat transfer rate from a heated metallic surface covered by a ceramic fabric with the intent of determining the effective emissivity'' of the combination of materials, studies of the wicking properties of ceramic fabrics, and the construction of fabric composite heat pipes to test their working properties under both steady state and transient conditions. Results of these experiments shown that fabric composite combinations have greatly enhanced effective emissivities'' resulting from the increases surface area of the fabric, ceramic fabrics can work very well as the wick for heat pipes, ceramic fabric heat pipes have been demonstrated to operate under typical space conditions, and large mass reductions are possible by using fabric composite heat pipes for heat rejection radiator systems.

Klein, A.C.; Gulshan-Ara, Z.; Kiestler, W.; Snuggerud, R.; Marks, T.S. (Department of Nuclear Engineering, Oregon State University, Corvallis, Oregon 97331 (United States))

1993-01-10T23:59:59.000Z

375

What's in Season from the Garden State  

E-Print Network [OSTI]

in the system. New Jersey is deficient in a distribution mechanism which respects and embraces seasonality or restaurants or have refrigerated trucks for deliveries. What the New Jersey wholesale produce distribution it with Jersey and bridge the gap in the system: Gaurino Sons Produce and Zone 7. Guarino Sons Produce Long

Goodman, Robert M.

376

1, 681707, 2004 Seasonal P cycling in  

E-Print Network [OSTI]

recycling that takes place in the water10 column. The DOP concentration exhibits two peaks during a seasonal the POP content decreases. This indicates two periods of increased phosphorus recycling activity The southern bight of the North Sea receives nutrients from domestic, industrial and agricultural wastewater

Paris-Sud XI, Université de

377

Pagosa Springs District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

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

378

Boise City Geothermal District Heating District Heating Low Temperatur...  

Open Energy Info (EERE)

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

379

San Bernardino District Heating District Heating Low Temperature...  

Open Energy Info (EERE)

San Bernardino District Heating District Heating Low Temperature Geothermal Facility Facility San Bernardino District Heating Sector Geothermal energy Type District Heating...

380

Kethcum District Heating District Heating Low Temperature Geothermal...  

Open Energy Info (EERE)

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

Note: This page contains sample records for the topic "heating season performance" 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

Philip District Heating District Heating Low Temperature Geothermal...  

Open Energy Info (EERE)

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

382

Midland District Heating District Heating Low Temperature Geothermal...  

Open Energy Info (EERE)

Midland District Heating District Heating Low Temperature Geothermal Facility Facility Midland District Heating Sector Geothermal energy Type District Heating Location Midland,...

383

Combined Heat and Power, Waste Heat, and District Energy | Department...  

Broader source: Energy.gov (indexed) [DOE]

Combined Heat and Power, Waste Heat, and District Energy Combined Heat and Power, Waste Heat, and District Energy Presentation-given at the Fall 2011 Federal Utility Partnership...

384

Waste Heat Management Options for Improving Industrial Process Heating Systems  

Broader source: Energy.gov [DOE]

This presentation covers typical sources of waste heat from process heating equipment, characteristics of waste heat streams, and options for recovery including Combined Heat and Power.

385

Guide to Geothermal Heat Pumps  

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

Geothermal Heat Pumps Work Using a heat exchanger, a geothermal heat pump can move heat from one space to another. In summer, the geothermal heat pump extracts heat from a building...

386

State heating oil and propane program. Final report, 1990--1991  

SciTech Connect (OSTI)

The following is a report of New Hampshire`s participation in the State Heating Oil and Propane Program (SHOPS) for the 1990--91 heating season. The program is a joint effort between participating states and the Department of Energy (DOE), Energy Information Administration (EYE) to collect retail price data for heating oil and propane through phone surveys of 25 oil and 20 propane retailers in New Hampshire. SHOPS is funded through matching grants from DOE and the participating state. (VC)

Not Available

1991-12-31T23:59:59.000Z

387

Performance Evaluation of Surveillance Systems Under Varying Conditions  

E-Print Network [OSTI]

/outdoor, different weather conditions (precipitation, wind, and brightness), different cameras of metrics. Visualization of the performance results has proven critical for understanding the weaknesses, as the weather varies, the seasons change, and the daily events unfold. Performance evaluation of automatic

Senior, Andrew

388

3D numerical simulation on fluid flow and heat transfer characteristics in multistage heat exchanger with slit fins  

Science Journals Connector (OSTI)

In this paper, a numerical investigation is performed for three-stage heat exchangers with plain plate fins and slit ... are arranged in a staggered way, and heat conduction in fins is considered. In order ... av...

W. Q. Tao; Y. P. Cheng; T. S. Lee

2007-11-01T23:59:59.000Z

389

Effect of alumina nanoparticles in the fluid on heat transfer in double-pipe heat exchanger system  

Science Journals Connector (OSTI)

This study was performed to investigate the convective heat transfer coefficient of nanofluids made of several alumina ... transformer oil which flow through a double pipe heat exchanger system in the laminar flo...

Byung-Hee Chun; Hyun Uk Kang; Sung Hyun Kim

2008-09-01T23:59:59.000Z

390

Sustainable heat extraction from abandoned mine tunnels: A numerical model  

Science Journals Connector (OSTI)

Abandoned mines are often associated with enduring liabilities which involve significant costs for decades after the decommissioning of the mine. Using a decommissioned mine as a geothermal resource can offset the environmental costs by supplying green heat to the communities living in and around the mine area. In this paper a numerical assessment of geothermal heat extraction from underground mine workings using an open loop geothermal system is carried out. In this study our focus is on fully flooded mines where the heat flow from the rock mass to the mine cavities is dominantly controlled by conduction in the rock mass. The sustainable heat flux into the mine workings is assessed using a transient two-dimensional axisymmetric heat transfer model. Finite volume method is applied to solve the model and simulate the transient temperature fields in the rock mass and within the water (flowing through cavities). The model is capable of controlling the rate of heat extraction through continuous adjustment of the rate of water flow through the mine. Sustainable rate of heat extraction is calculated for seasonally varied heat loads and for different project life cycles. It is shown that with proper resource management each kilometre of a typical deep underground mine tunnel can produce about 150?kW of usable heat in a sustainable manner. The model is validated by comparing its results with other published models and realistic data available from Springhill mine Nova Scotia Canada. It is found that the sustainable heat extraction is controlled dominantly by virgin rock temperature thermal conductivity of the rock mass and seasonal heat load variations.

S. A. Ghoreishi Madiseh; Mory M. Ghomshei; F. P. Hassani; F. Abbasy

2012-01-01T23:59:59.000Z

391

Air heating of passive houses in cold climates: Investigation using detailed dynamic simulations  

Science Journals Connector (OSTI)

Abstract The passive house (PH) standard was originally defined for Central Europe and has subsequently been applied to many cold climate countries. In these conditions, the relation between this standard and the air heating (AH) is not clear while both concepts are usually associated. Furthermore, the AH provides a way to simplify the space-heating distribution system. The present contribution investigates the feasibility of the AH concept in PH along with its challenges in terms of thermal dynamics: the magnitude of the AH temperature needed, the temperature difference between rooms, the impact of internal gains, the influence of thermal losses from ventilation ducts and the AH control. This is performed using detailed dynamic simulations (TRNSYS) on a typical detached house typology. Practically, four cold climate zones are considered as well as different insulation levels and construction materials. Results show limitations related to a centralized AH as well as provide guidelines for a consistent AH design in cold climates. In addition, a simple analytical method used for the design of German PH is tested and proved accurate enough to estimate the maximal AH temperature during the heating season.

Laurent Georges; Monica Berner; Hans Martin Mathisen

2014-01-01T23:59:59.000Z

392

Woven heat exchanger  

DOE Patents [OSTI]

This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

Piscitella, R.R.

1984-07-16T23:59:59.000Z

393

Towards Intelligent District Heating.  

E-Print Network [OSTI]

??A district heating system consists of one or more production units supplying energy in the form of heated water through a distribution pipe network to… (more)

Johansson, Christian

2010-01-01T23:59:59.000Z

394

Total Space Heat-  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

Buildings Energy Consumption Survey: Energy End-Use Consumption Tables Total Space Heat- ing Cool- ing Venti- lation Water Heat- ing Light- ing Cook- ing Refrig- eration...

395

ARM - Heat Index Calculations  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox Lesson Plans Heat Index Calculations Heat Index is an index that combines air temperature and relative...

396

Models for the Prediction of Fouling in Crude Oil Pre-Heat Trains  

E-Print Network [OSTI]

Fouling has two significant effects upon pre-heat train performance. Firstly, any of layer of foulant on the heat transfer surface presents a resistance to heat transfer. This thermal resistance increases as the layer builds up, so fouling reduces...

Yeap, B. L.; Wilson, D. I.; Polley, G. T.

397

Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems  

E-Print Network [OSTI]

tool for geothermal water loop heat pump systems, 9thInternational IEA Heat Pump Conference, Zürich, Switzerland,Performance of ground source heat pump system in a near-zero

Hong, Tainzhen

2010-01-01T23:59:59.000Z

398

Experimental investigation on system with combination of ground-source heat pump and solar collector  

Science Journals Connector (OSTI)

This paper presents the heating performance and energy distribution of a system with the combination of ground-source heat pump and solar collector or a solar-assisted ground-source heat pump system (SAGSHPS) by ...

Tao Hu ? ?; Jialing Zhu ???; Wei Zhang ? ?

2013-06-01T23:59:59.000Z

399

Pacific Adaptation Strategy Assistance Program Dynamical Seasonal Forecasting  

E-Print Network [OSTI]

Pacific Adaptation Strategy Assistance Program Dynamical Seasonal Forecasting Seasonal Prediction · POAMA · Issues for future Outline #12;Pacific Adaptation Strategy Assistance Program Major source Adaptation Strategy Assistance Program El Nino Mean State · Easterlies westward surface current upwelling

Lim, Eun-pa

400

Original article Belowground biomass seasonal variation in two  

E-Print Network [OSTI]

Original article Belowground biomass seasonal variation in two Neotropical savannahs (Brazilian March 2001) Abstract ­ The belowground biomass of two types of ecosystems, frequently burned open by flotation and sieving. Belowground biomass showed significant seasonal variation, values being higher during

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "heating season performance" 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

The Seasonal Cycle over the United States and Mexico  

Science Journals Connector (OSTI)

The annual cycle occupies a unique position in the spectra of meteorological time series. This cycle and its first three harmonics are extracted from the series as a seasonal cycle. The distributions of the annual and seasonal cycles are studied ...

Vernon E. Kousky; S. Srivatsangam

1983-01-01T23:59:59.000Z

402

Reduce Waste and Save Energy this Holiday Season | Department...  

Office of Environmental Management (EM)

Reduce Waste and Save Energy this Holiday Season Reduce Waste and Save Energy this Holiday Season December 5, 2014 - 9:55am Addthis Wrap your gifts with recycled paper to reduce...

403

St. Augustinegrass Warm-season turfgrass. Prefers full sun, but  

E-Print Network [OSTI]

St. Augustinegrass Warm-season turfgrass. Prefers full sun, but has a high tolerance for shade-season grass. It does best in full sun and high temperatures. Goes dormant and turns brown in winter. Very

Ishida, Yuko

404

Industrial heat pumps - types and costs  

SciTech Connect (OSTI)

Confusion about energy savings and economics is preventing many potentially beneficial applications for industrial heat pumps. The variety of heat pumps available and the lack of a standard rating system cause some of this confusion. The authors illustrate how a simple categorization based on coefficient of performance (COP) can compare the cost of recovering waste energy with heat pumps. After evaluating examples in which the cost of energy delivered was calculated based on estimates of capital cost, operating costs, and maintenance costs, they compare heat pumps from the various categories on the basis of economics. 6 references, 6 figures, 1 table.

Chappell, R.N.; Bliem, C.J. Jr.; Mills, J.I.; Demuth, O.J.; Plaster, D.S.

1985-08-01T23:59:59.000Z

405

AT 351 Lab 3: Seasons and Surface Temperature (Ch. 3)  

E-Print Network [OSTI]

an important role in an area's local vertical temperature distribution. Below, Figure 1 shows the verticalAT 351 Lab 3: Seasons and Surface Temperature (Ch. 3) Question #1: Seasons (20 pts) A. In your own words, describe the cause of the seasons. B. In the Northern Hemisphere we are closer to the sun during

Rutledge, Steven

406

Rotary magnetic heat pump  

DOE Patents [OSTI]

A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

Kirol, L.D.

1987-02-11T23:59:59.000Z

407

Managing Warm-season Improved Pastures  

E-Print Network [OSTI]

. However, west of a line from Corpus Christi through San Antonio to Fort Worth, rainfall is greatly reduced year round and spring calving is preferred. The rainfall pattern in this area corresponds to for- age production as shown in Fig. 1. Spring calving... season corresponds to better forage quality and quantity in native rangeland and improved pastures. Because improved small grain pastures must be irrigated in many areas of west Texas, the cost of producing improved winter forages for cow-calf op...

Stichler, Charles; Prostko, Eric P.; Livingston, Stephen

1998-10-09T23:59:59.000Z

408

Influences on seasonal ski worker intention to return and indicators and standards of quality for seasonal ski jobs  

E-Print Network [OSTI]

of the requirements for the degree of MASTER OF SCIENCF. August 2002 Major Subject: Recreation, Park and Tourism Sciences INFLUENCES ON SEASONAL SKI WORKER INTENTION TO RETURN AND INDICATORS AND STANDARDS OF QUALiTY FOR SEASONAL SKI JOBS A Thesis By MATTHEW D... 'Lear (He c of partment) August 2002 Major Subject: Recreation, Park and Tourism Sciences ABSTRACT Influences on Seasonal Ski Worker Intention to Return and Indicators and Standards of Quality for Seasonal Ski Jobs. (August 2002) Matthew D. Ismert...

Ismert, Matthew D

2012-06-07T23:59:59.000Z

409

Thulium-170 heat source  

SciTech Connect (OSTI)

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

Walter, C.E.; Van Konynenburg, R.; VanSant, J.H.

1990-09-06T23:59:59.000Z

410

Thulium-170 heat source  

DOE Patents [OSTI]

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.

Walter, Carl E. (Pleasanton, CA); Van Konynenburg, Richard (Livermore, CA); VanSant, James H. (Tracy, CA)

1992-01-01T23:59:59.000Z

411

Heat Treating Apparatus  

DOE Patents [OSTI]

Apparatus for heat treating a heat treatable material including a housing having an upper opening for receiving a heat treatable material at a first temperature, a lower opening, and a chamber therebetween for heating the heat treatable material to a second temperature higher than the first temperature as the heat treatable material moves through the chamber from the upper to the lower opening. A gas supply assembly is operatively engaged to the housing at the lower opening, and includes a source of gas, a gas delivery assembly for delivering the gas through a plurality of pathways into the housing in countercurrent flow to movement of the heat treatable material, whereby the heat treatable material passes through the lower opening at the second temperature, and a control assembly for controlling conditions within the chamber to enable the heat treatable material to reach the second temperature and pass through the lower opening at the second temperature as a heated material.

De Saro, Robert (Annandale, NJ); Bateman, Willis (Sutton Colfield, GB)

2002-09-10T23:59:59.000Z

412

Preliminary survey and evaluation of nonaquifer thermal energy storage concepts for seasonal storage  

SciTech Connect (OSTI)

Thermal energy storage enables the capture and retention of heat energy (or cold) during one time period for use during another. Seasonal thermal energy storage (STES) involves a period of months between the input and recovery of energy. The purpose of this study was to make a preliminary investigation and evaluation of potential nonaquifer STES systems. Current literature was surveyed to determine the state of the art of thermal energy storage (TES) systems such as hot water pond storage, hot rock storage, cool ice storage, and other more sophisticated concepts which might have potential for future STES programs. The main energy sources for TES principally waste heat, and the main uses of the stored thermal energy, i.e., heating, cooling, and steam generation are described. This report reviews the development of sensible, latent, and thermochemical TES technologies, presents a preliminary evaluation of the TES methods most applicable to seasonal storage uses, outlines preliminary conclusions drawn from the review of current TES literature, and recommends further research based on these conclusions. A bibliography of the nonaquifer STES literature review, and examples of 53 different TES concepts drawn from the literature are provided. (LCL)

Blahnik, D.E.

1980-11-01T23:59:59.000Z

413

"Nanotechnology Enabled Advanced Industrial Heat Transfer Fluids"  

SciTech Connect (OSTI)

ABSTRACT Nanotechnology Enabled Advanced industrial Heat Transfer Fluids” Improving the efficiency of Industrial Heat Exchangers offers a great opportunity to improve overall process efficiencies in diverse industries such as pharmaceutical, materials manufacturing and food processing. The higher efficiencies can come in part from improved heat transfer during both cooling and heating of the material being processed. Additionally, there is great interest in enhancing the performance and reducing the weight of heat exchangers used in automotives in order to increase fuel efficiency. The goal of the Phase I program was to develop nanoparticle containing heat transfer fluids (e.g., antifreeze, water, silicone and hydrocarbon-based oils) that are used in transportation and in the chemical industry for heating, cooling and recovering waste heat. Much work has been done to date at investigating the potential use of nanoparticle-enhanced thermal fluids to improve heat transfer in heat exchangers. In most cases the effect in a commercial heat transfer fluid has been marginal at best. In the Phase I work, we demonstrated that the thermal conductivity, and hence heat transfer, of a fluid containing nanoparticles can be dramatically increased when subjected to an external influence. The increase in thermal conductivity was significantly larger than what is predicted by commonly used thermal models for two-phase materials. Additionally, the surface of the nanoparticles was engineered so as to have a minimal influence on the viscosity of the fluid. As a result, a nanoparticle-laden fluid was successfully developed that can lead to enhanced heat transfer in both industrial and automotive heat exchangers

Dr. Ganesh Skandan; Dr. Amit Singhal; Mr. Kenneth Eberts; Mr. Damian Sobrevilla; Prof. Jerry Shan; Stephen Tse; Toby Rossmann

2008-06-12T23:59:59.000Z

414

Thermoelectric heat exchange element  

DOE Patents [OSTI]

A thermoelectric heat exchange module includes a first substrate including a heat receptive side and a heat donative side and a series of undulatory pleats. The module may also include a thermoelectric material layer having a ZT value of 1.0 or more disposed on at least one of the heat receptive side and the heat donative side, and an electrical contact may be in electrical communication with the thermoelectric material layer.

Callas, James J. (Peoria, IL); Taher, Mahmoud A. (Peoria, IL)

2007-08-14T23:59:59.000Z

415

Chemical heat pump project: Final report  

SciTech Connect (OSTI)

Solid/vapor working media can be used as working fluids in industrial heat pumps for heat amplifier and temperature amplifier concepts. This report describes the theoretical investigation of candidate solid/vapor fluids and the development of single and multi-stage heat pump cycles. Ammoniated complex compounds, hydrated complex compounds, metal carbonate-metal oxide media, and metal hydrides were investigated. A preliminary computer model was developed to predict the performance characteristics of a single-stage complex compound temperature amplifier and to outline the limitations of such concepts. A preliminary first cost calculation was performed in order to determine the economical feasibility of solid/vapor industrial heat pumps in comparison to boilers nd state-of-the-art heat pump equipment.

Not Available

1985-01-01T23:59:59.000Z

416

Turning low solar heat gain windows into energy savers in winter  

SciTech Connect (OSTI)

The reduction in summer peak cooling loads of buildings with a large ratio of window to floor areas is often achieved by windows with a low solar heat gain coefficient (SHGC). These windows are typically double glazed with the exterior pane tinted or selectively absorbing. Absorbed solar radiation is rejected to the environment. This is undesirable in the cold season. The authors suggest that by turning south-facing windows by 180{degree} for the duration of the cold season, the solar heat gain of these windows can be increased significantly. By means of a computer simulation, they estimate seasonal energy savings for a model room in several climates. The effect of building heat capacity on the savings is also studied. Windows whose positions can be reversed for ease of cleaning are commercially available. This study shows that in a suitable climate the achievable savings easily compensate for the additional effort and possible investment over the lifetime of the window.

Feuermann, D.; Novoplansky, A. [Ben-Gurion Univ. of the Negev, Sede Boker (Israel). Jacob Blaustein Inst. for Desert Research

1996-10-01T23:59:59.000Z

417

Performance prediction of a solar thermal energy system using artificial neural networks  

Science Journals Connector (OSTI)

Abstract This paper describes in details an application of artificial neural networks (ANNs) to predict the performance of a solar thermal energy system (STES) used for domestic hot water and space heating application. Experiments were conducted on the STES under a broad range of operating conditions during different seasons and Canadian weather conditions in Ottawa, over the period of March 2011 through December 2012 to assess the system performance. These experimental data were utilised for training, validating and testing the proposed ANN model. The model was applied to predict various performance parameters of the system, namely the preheat tank stratification temperatures, the heat input from the solar collectors to the heat exchanger, the heat input to the auxiliary propane-fired tank, and the derived solar fractions. The back-propagation learning algorithm with two different variants, the Levenberg–Marguardt (LM) and scaled conjugate gradient (SCG) algorithms were used in the network. It was found that the optimal algorithm and topology were the LM and the configuration with 10 inputs, 20 hidden and 8 output neurons/outputs, respectively. The preheat tank temperature and solar fraction predictions agreed very well with the experimental values using the testing data sets. The \\{ANNs\\} predicted the preheat water tank stratification temperatures and the solar fractions of the STES within less that ±3% and ±10% errors, respectively. The results confirmed the effectiveness of this method and provided very good accuracy even when the input data are distorted with different levels of noise. Moreover, the results of this study demonstrate that the ANN approach can provide high accuracy and reliability for predicting the performance of complex energy systems such as the one under investigation. Finally, this method can also be exploited as an effective tool to develop applications for predictive performance monitoring system, condition monitoring, fault detection and diagnosis of STES.

Wahiba Yaïci; Evgueniy Entchev

2014-01-01T23:59:59.000Z

418

Cab Heating and Cooling  

SciTech Connect (OSTI)

Schneider National, Inc., SNI, has concluded the Cab Heating and Cooling evaluation of onboard, engine off idling solutions. During the evaluation period three technologies were tested, a Webasto Airtronic diesel fired heater for cold weather operation, and two different approaches to cab cooling in warm weather, a Webasto Parking Cooler, phase change storage system and a Bergstrom Nite System, a 12 volt electrical air conditioning approach to cooling. Diesel fired cab heaters were concluded to provide adequate heat in winter environments down to 10 F. With a targeted idle reduction of 17%, the payback period is under 2 years. The Webasto Parking Cooler demonstrated the viability of this type of technology, but required significant driver involvement to achieve maximum performance. Drivers rated the technology as ''acceptable'', however, in individual discussions it became apparent they were not satisfied with the system limitations in hot weather, (over 85 F). The Bergstrom Nite system was recognized as an improvement by drivers and required less direct driver input to operate. While slightly improved over the Parking Cooler, the hot temperature limitations were only slightly better. Neither the Parking Cooler or the Nite System showed any payback potential at the targeted 17% idle reduction. Fleets who are starting at a higher idle baseline may have a more favorable payback.

Damman, Dennis

2005-10-31T23:59:59.000Z

419

Heat Integrate Heat Engines in Process Plants  

E-Print Network [OSTI]

and refrigeration systems. In many instances these real heat engines may appear as a complex process consisting of flash vessels, heat exchangers, compressors, furnaces, etc. See Figure 18a, which shows a simplified diagram of a "steam Rankine cycle." How... and rejection profiles of the real machine. For example, the heat acceptance and re jection profiles for the steam Rankine cycle shown in Figure 18a have been drawn on T,H coordinates in Figure 18b. Thus providing we know the heat acceptance and rejection...

Hindmarsh, E.; Boland, D.; Townsend, D. W.

420

The Future of Home Heating | Department of Energy  

Office of Environmental Management (EM)

Information Exchange on Pyrolysis Oil: Potential for a Renewab;e Heating Oil Substation Fuel in New England Performance of Biofuels and Biofuel Blends Biofuels Report Final...

Note: This page contains sample records for the topic "heating season performance" 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.


421

Standard Method of Test for Integrated Heat Pumps  

Broader source: Energy.gov [DOE]

Lead Performer: Oak Ridge National Laboratory - Oak Ridge, TN Partners: -- ASHRAE - Atlanta, GA -- Air Conditioning, Heating, and Refrigeration Institute (AHRI) - Arlington, VA

422

Investigations of novel heat pump systems for low carbon homes.  

E-Print Network [OSTI]

??The European standard EN15450 states that the Coefficient of Performance (COP) target range for a Ground Source Heat Pump (GSHP) installation should lie within the… (more)

Mempouo, B.

2011-01-01T23:59:59.000Z

423

Trimming of a ground source heat pump system in Saltsjöbaden.  

E-Print Network [OSTI]

?? The real performance of ground source heat pumps systems are not precisely highlighted in most cases, especially when it comes to installations older than… (more)

Garnier, Michel

2014-01-01T23:59:59.000Z

424

Using Waste Heat for External Processes | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A BestPractices Process Heating Technical Brief Consider Installing a Condensing Economizer...

425

Heat pipe cooled heat rejection subsystem modelling for nuclear electric propulsion. Final report  

SciTech Connect (OSTI)

NASA LeRC is currently developing a FORTRAN based computer model of a complete nuclear electric propulsion (NEP) vehicle that can be used for piloted and cargo missions to the Moon or Mars. Proposed designs feature either a Brayton or a K-Rankine power conversion cycle to drive a turbine coupled with rotary alternators. Both ion and magnetoplasmodynamic (MPD) thrusters will be considered in the model. In support of the NEP model, Rocketdyne is developing power conversion, heat rejection, and power management and distribution (PMAD) subroutines. The subroutines will be incorporated into the NEP vehicle model which will be written by NASA LeRC. The purpose is to document the heat pipe cooled heat rejection subsystem model and its supporting subroutines. The heat pipe cooled heat rejection subsystem model is designed to provide estimate of the mass and performance of the equipment used to reject heat from Brayton and Rankine cycle power conversion systems. The subroutine models the ductwork and heat pipe cooled manifold for a gas cooled Brayton; the heat sink heat exchanger, liquid loop piping, expansion compensator, pump and manifold for a liquid loop cooled Brayton; and a shear flow condenser for a K-Rankine system. In each case, the final heat rejection is made by way of a heat pipe radiator. The radiator is sized to reject the amount of heat necessary.

Moriarty, M.P.

1993-11-01T23:59:59.000Z

426

Heat flux solarimeter  

SciTech Connect (OSTI)

The solarimeter presented in this work is easy to assemble. It is calibrated and its performance is validated by means of Hottel's method. Finally, the curves obtained with this solarimeter are compared to the ones obtained with a commercial solarimeter. This device is based on the evaluation of the heat flow in a metal rod. In consequence, measurements are not affected by ambient temperature variations. On the other hand, there is a linear relationship between the temperatures measured at the rod ends and the incident radiation, as can be concluded both from the theory of its operation and the calibration lines obtained. The results obtained from the global irradiance measurements in the area of Los Polvorines (Buenos Aires Province), together with a preliminary evaluation of the solarimeter's response time, are presented in this work. (author)

Sartarelli, A.; Vera, S.; Cyrulies, E. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Echarri, R. [Instituto de Desarrollo Humano, Univ. Nac. de Gral. Sarmiento (IDH, UNGS), Los Polvorines (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Samson, I. [INTEC (Instituto Tecnologico Santo Domingo), Santo Domingo (Dominican Republic)

2010-12-15T23:59:59.000Z

427

Holographic Heat Engines  

E-Print Network [OSTI]

It is shown that in theories of gravity where the cosmological constant is considered a thermodynamic variable, it is natural to use black holes as heat engines. Two examples are presented in detail using AdS charged black holes as the working substance. We notice that for static black holes, the maximally efficient traditional Carnot engine is also a Stirling engine. The case of negative cosmological constant supplies a natural realization of these engines in terms of the field theory description of the fluids to which they are holographically dual. We first propose a precise picture of how the traditional thermodynamic dictionary of holography is extended when the cosmological constant is dynamical and then conjecture that the engine cycles can be performed by using renormalization group flow. We speculate about the existence of a natural dual field theory counterpart to the gravitational thermodynamic volume.

Clifford V. Johnson

2014-09-04T23:59:59.000Z

428

Summertime results from the Class B passive-solar performance-monitoring program  

SciTech Connect (OSTI)

The DOE/SERI Class B passive solar monitoring program is designed to provide, at relatively low cost, accurate and consistent real-time estimates of building thermal performance, as well as detailed data regarding climate, indoor temperatures, and purchased energy needs. As part of this program, a microprocessor-based data acquisition system has been installed in each of ten passive solar houses in the Denver area, primarily to evaluate heating-season performance. During the summer, however, the monitoring systems are used to study the overheating tendencies of the buildings. Examination of the conditions that lead to overheating, using graphical and statistical techniques, will provide insight into the solar design practices that provide the most comfortable summer environment.

Swisher, J.

1981-07-01T23:59:59.000Z

429

SEASONAL DISAPPEARANCE OF FAR-INFRARED HAZE IN TITAN'S STRATOSPHERE  

SciTech Connect (OSTI)

A far-infrared emission band attributed to volatile or refractory haze in Titan's stratosphere has been decreasing in intensity since Cassini's arrival in 2004. The 220 cm{sup -1} feature, first seen by the Voyager Infrared Interferometer Spectrometer, has only been found in Titan's winter polar region. The emission peaks at about 140 km altitude near the winter stratospheric temperature minimum. Observations recorded over the period 2004-2012 by the Composite Infrared Spectrometer on Cassini show a decrease in the intensity of this feature by about a factor of four. Possible seasonal causes of this decline are an increase in photolytic destruction of source chemicals at high altitude, a lessening of condensation as solar heating increased, or a weakening of downwelling of vapors. As of early 2012, the 220 cm{sup -1} haze has not yet been detected in the south. The haze composition is unknown, but its decrease is similar to that of HC{sub 3}N gas in Titan's polar stratosphere, pointing to a nitrile origin.

Jennings, Donald E.; Anderson, C. M.; Flasar, F. M.; Cottini, V. [Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Samuelson, R. E.; Nixon, C. A.; Kunde, V. G.; Achterberg, R. K. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); De Kok, R. [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands); Coustenis, A.; Vinatier, S. [LESIA, Observatoire de Paris-Meudon, 92195 Meudon Cedex (France); Calcutt, S. B., E-mail: donald.e.jennings@nasa.gov [Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom)

2012-07-20T23:59:59.000Z

430

An evaluation of heat flow transducers as a means of determining soil heat flow  

E-Print Network [OSTI]

provided to the Micrometeorology Section, Department of Oceanography and Meteorology, ARM College of Texas by the Signal Corps of the United States Army, under Contract No. DA 36-039 AMC-02195 (E). The heat flow plates used in this study were provided... surface soil heat flow. The results show that acceptable performance of the plates in the measurement of heat flow is possible although in general should not be expected without thorough testing, and even then there are restrictive considerations...

King, Barney L. D

2012-06-07T23:59:59.000Z

431

Revamping Pre-Heat Trains for Energy Saving  

E-Print Network [OSTI]

In this paper we look at the principles underlying the revamping of pre-heat trains to save energy through increased heat recovery. For brevity, we do not consider throughput changes. Only pre-heat train performance is considered. The interaction...

Yeap, B. L.; Wilson, I.; Pretty, B.; Polley, G. T.

432

Additional Heating Experiments on JET with Ion-Cyclotron Waves  

Science Journals Connector (OSTI)

...research-article Additional Heating Experiments on JET with Ion-Cyclotron Waves J. Jacquinot...tokamak plasma heating with ion-cyclotron waves are reviewed...vicinity of the cyclotron resonance and preliminary...performed. The best heating conditions are...

1987-01-01T23:59:59.000Z

433

Heat transfer system  

DOE Patents [OSTI]

A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

McGuire, Joseph C. (Richland, WA)

1982-01-01T23:59:59.000Z

434

Wound tube heat exchanger  

DOE Patents [OSTI]

What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

Ecker, Amir L. (Duncanville, TX)

1983-01-01T23:59:59.000Z

435

Heat Exchangers for Solar Water Heating Systems | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems Heat Exchangers for Solar Water Heating Systems May 30, 2012 - 3:40pm Addthis Image of a heat exchanger. | Photo from iStockphoto.com Image of a heat exchanger. | Photo from iStockphoto.com Solar water heating systems use heat exchangers to transfer solar energy absorbed in solar collectors to the liquid or air used to heat water or a space. Heat exchangers can be made of steel, copper, bronze, stainless steel, aluminum, or cast iron. Solar heating systems usually use copper, because it is a good thermal conductor and has greater resistance to corrosion. Types of Heat Exchangers Solar water heating systems use three types of heat exchangers: Liquid-to-liquid A liquid-to-liquid heat exchanger uses a heat-transfer fluid that

436

IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH  

E-Print Network [OSTI]

00149 -1- 10th IEA Heat Pump Conference 2011, 16 - 19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH R-1234yf Sorina Mortada, Ph.D. student, Center for Energy and Processes Abstract: Significant improvements in energy performance of air-to-air heat pumps are the major reason

Paris-Sud XI, Université de

437

Natural convection heat exchangers for solar water heating systems. Technical progress report, November 15, 1996--January 14, 1997  

SciTech Connect (OSTI)

The goals of this project are: (1) to develop guidelines for the design and use of thermosypohon side-arm heat exchangers in solar domestic water heating systems, and (2) to establish appropriate modeling and testing criteria for evaluating the performance of systems using this type of heat exchanger.

Davidson, J.H.

1998-06-01T23:59:59.000Z

438

Using Exergy Analysis Methodology to Assess the Heating Efficiency of an Electric Heat Pump  

E-Print Network [OSTI]

The authors, using exergy analysis methodology, propose that it should consider not only the COP (coefficient of Performance) value of the electric power heat pump set (EPHPS/or HP set), but also the exergy loss at the heating exchanger of the HP...

Ao, Y.; Duanmu, L.; Shen, S.

2006-01-01T23:59:59.000Z

439

Author's personal copy Pyroelectric waste heat energy harvesting using heat conduction  

E-Print Network [OSTI]

pump, cryogenic refrigeration, and air liquefaction applications [3]. Organic Rankine cycles use heat harvesting Olsen cycle a b s t r a c t Waste heat can be directly converted into electrical energy by performing the Olsen cycle on pyroelectric materials. The Olsen cycle consists of two isothermal and two

Pilon, Laurent

440

E-Print Network 3.0 - aerodynamic heating Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

COLLEGE OF ENGINEERING Research Areas Summary: ) Heat Transfer Solid Mechanics Energy Systems Air-Conditioner Performance Evaluations Alternate... and Diagnostic...

Note: This page contains sample records for the topic "heating season performance" 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

DHE (downhole heat exchangers). [Downhole Heat Exchangers (DHE)  

SciTech Connect (OSTI)

The use of downhole heat exchangers (DHE) for residential or commercial space and domestic water heating and other applications has several desirable features. Systems are nearly or completely passive -- that is, no or very little geothermal water or steam is produced from the well either reducing or completely eliminating surface environmental concerns and the need for disposal systems or injection wells. Initial cost of pumps and installation are eliminated or reduced along with pumping power costs and maintenance costs associated with pumping often corrosive geothermal fluids. Many residential and small commercial systems do not require circulating pumps because the density difference in the incoming and outgoing sides of the loop are sufficient to overcome circulating friction losses in the entire system. The major disadvantage of DHEs is their dependence on natural heat flow. In areas where geological conditions provide high permeability and a natural hydraulic gradient, DHEs can provide a substantial quantity of heat. A single 500-ft (152 m) well in Klamath Falls, Oregon, supplies over one megawatt thermal and output is apparently limited by the surface area of pipe that can be installed in the well bore. In contrast, DHEs used in conjunction with heat pumps may supply less than 8 KW from a well of similar depth. Here output is limited by conductive heat flow with perhaps a small contribution from convection near the well bore. The highest capacity DHE reported to date, in Turkey, supplies 6 MW thermal from an 820-ft (250 m) well. There were two main goals for this project. The first was to gather, disseminate and exchange internationally information on DHES. The second was to perform experiments that would provide insight into well bore/aquifer interaction and thereby provide more information on which to base DHE designs. 27 refs., 31 figs., 3 tabs.

Culver, G.

1990-11-01T23:59:59.000Z

442

Metal buildings study: performance of materials and field validation  

SciTech Connect (OSTI)

A 5000 square-foot metal building located at Brookhaven National Laboratory has been monitored over a winter season. Energy flows through wall sections were monitored using portable calorimeters. Air infiltration was measured using perfluorocarbon tracers, and the associated heat losses were calculated. Slab losses were assessed through a comparison of measured temperature gradients with results obtained through the use of heat-flow meters. The effect of thermal bridges and compressed insulation in locations where support beams are joined to the exterior skin was found to increase heat losses significantly. A retrofit strategy including spray insulation of beams is projected to save 30% on heating energy.

Loss, W.

1987-12-01T23:59:59.000Z

443

Performance of slash pine (Pinus elliottii Engelm.) containerized rooted cuttings and bare-root seedlings established on five planting dates in the flatlands of western Louisiana  

E-Print Network [OSTI]

The forest product industry is keenly interested in extending the normal planting season, as well as in the comparative field performance of standard nursery bare-root seedlings and containerized rooted cuttings. The effect of seasonal planting...

Akgul, Alper

2005-08-29T23:59:59.000Z

444

Geothermal Heat Pumps  

Broader source: Energy.gov [DOE]

The Geothermal Technologies Office focuses only on electricity generation. For additional information about geothermal heating and cooling and ground source heat pumps, please visit the U.S. Department of Energy (DOE)'s Buildings Technologies Office.

445

Residential heating oil price  

Annual Energy Outlook 2013 [U.S. Energy Information Administration (EIA)]

heating oil price decreases The average retail price for home heating oil fell 6.3 cents from a week ago to 2.91 per gallon. That's down 1.10 from a year ago, based on the...

446

Residential heating oil price  

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

heating oil price decreases The average retail price for home heating oil fell 7.5 cents from a week ago to 2.84 per gallon. That's down 1.22 from a year ago, based on the...

447

Residential heating oil price  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

heating oil price decreases The average retail price for home heating oil fell 7.6 cents from a week ago to 2.97 per gallon. That's down 1.05 from a year ago, based on the...

448

Residential heating oil price  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

heating oil price decreases The average retail price for home heating oil fell 3.6 cents from a week ago to 3.04 per gallon. That's down 99.4 cents from a year ago, based on the...

449

Method for converting heat energy to mechanical energy with monochlorotetrafluoroethane  

SciTech Connect (OSTI)

Monochlorotetrafluoroethane is useful as a power fluid with particular suitability for large scale Rankine cycle applications based on systems with moderate temperature heat sources. The fluid is utilized in a Rankine cycle application by vaporizing the fluid by passing the same in heat exchange relationship with a heat source and utilizing the kinetic energy of the resulting expanding vapors to perform work. In this manner heat energy is converted to mechanical energy.

Allen, R.A.; Murphy, K.P.; Stiel, L.I.

1980-09-30T23:59:59.000Z

450

Building America Webinar: High Performance Space Conditioning...  

Energy Savers [EERE]

Kohta Ueno, Building Science Corporation. Kohta will discuss BSC's research on ductless heat pumps versus mini-splits being used in high performance (high R value enclosurelow...

451

Performance assessment of low-energy buildings in central Argentina  

Science Journals Connector (OSTI)

This paper summarizes the results obtained from the energy and thermal performance assessment of residential and non-residential low-energy buildings that were designed to minimize fossil energy use. They are located in the province of La Pampa, central Argentina, in a temperate continental climate that shows extreme hot and cold records during the summer and winter seasons, respectively. The common applied technologies for saving energy were passive solar heating, natural ventilation for cooling and daylighting. The glazing area in the principal functional spaces facing to the North oscillates between 11 and 17% of the building useful areas. All the studied buildings are massive, with the exception of an auditorium that was designed with a lightweight insulated technology. The mean thermal transmittance of the envelope is 0.45 W/(m2 K). Double glazing and hermetic carpentry were used to reduce thermal losses (U-value = 2.8 W/(m2 K)). The volumetric heat loss coefficient (G-value) oscillates between 0.90 and 1.00 W/(m3 K). During the design and thermal simulation convective-radiative heat transfer coefficients were estimated through a dimensional equation (h = 5.7 + 3.8 ws, wind speed). On internal surfaces, convective-radiative heat transfer coefficients of 8 and 6 W/(m2 °C) (for surfaces with and without solar gain, respectively) were applied. The monitoring process provided information on the energy and thermal behaviour under use and non-use conditions. The measured value of energy consumption was similar to the expected value that was used during the pre-design stage. Building technologies work well during the winter season, allowing 50–80% of energy savings. However, overheating is still an unresolved problem during the summer. Interviews with occupants revealed that they need both, information about functional details, and good-practice guidance to manage thermal issues of the building. In most cases, the annual consumption of energy was lower than those established by the Low Energy Housing German Standards and the Minirgie Switzerland Certificate. Despite their relative cost increase during the last years, the use of insulation technology and the application of passive solar devices involved an extra cost of only 3% in our works. Provided the expected depletion of natural gas production in the coming decade, the importance of applying energy-efficiency guidelines will increase very soon in Argentina in order to match the requirements of a new national energy matrix.

C. Filippín; A. Beascochea

2007-01-01T23:59:59.000Z

452

MA HEAT Loan Overview  

Broader source: Energy.gov [DOE]

Presents information on the success of Massachusetts's HEAT loan offerings and how the financing tool is funded.

453

Solar heat receiver  

DOE Patents [OSTI]

A receiver is described for converting solar energy to heat a gas to temperatures from 700 to 900/sup 0/C. The receiver is formed to minimize impingement of radiation on the walls and to provide maximum heating at and near the entry of the gas exit. Also, the receiver is formed to provide controlled movement of the gas to be heated to minimize wall temperatures. The receiver is designed for use with gas containing fine heat absorbing particles, such as carbon particles.

Hunt, A.J.; Hansen, L.J.; Evans, D.B.

1982-09-29T23:59:59.000Z

454

Electric resistive space heating  

Science Journals Connector (OSTI)

The cost of heating residential buildings using electricity is compared to the cost employing gas or oil. (AIP)

David Bodansky

1985-01-01T23:59:59.000Z

455

Castor-1C spent fuel storage cask decay heat, heat transfer, and shielding analyses  

SciTech Connect (OSTI)

This report documents the decay heat, heat transfer, and shielding analyses of the Gesellschaft fuer Nuklear Services (GNS) CASTOR-1C cask used in a spent fuel storage demonstration performed at Preussen Elektra's Wurgassen nuclear power plant. The demonstration was performed between March 1982 and January 1984, and resulted in cask and fuel temperature data and cask exterior surface gamma-ray and neutron radiation dose rate measurements. The purpose of the analyses reported here was to evaluate decay heat, heat transfer, and shielding computer codes. The analyses consisted of (1) performing pre-look predictions (predictions performed before the analysts were provided the test data), (2) comparing ORIGEN2 (decay heat), COBRA-SFS and HYDRA (heat transfer), and QAD and DOT (shielding) results to data, and (3) performing post-test analyses if appropriate. Even though two heat transfer codes were used to predict CASTOR-1C cask test data, no attempt was made to compare the two codes. The codes are being evaluated with other test data (single-assembly data and other cask data), and to compare the codes based on one set of data may be premature and lead to erroneous conclusions.

Rector, D.R.; McCann, R.A.; Jenquin, U.P.; Heeb, C.M.; Creer, J.M.; Wheeler, C.L.

1986-12-01T23:59:59.000Z

456

Thermodynamic and heat transfer analysis of heat recovery from engine test cell by Organic Rankine Cycle  

Science Journals Connector (OSTI)

During manufacture of engines, evaluation of engine performance is essential. This is accomplished in test cells. During the test, a significant portion of heat energy released by the fuel is wasted. In this stud...

Naser Shokati; Farzad Mohammadkhani; Navid Farrokhi…

2014-12-01T23:59:59.000Z

457

Liquid heat capacity lasers  

DOE Patents [OSTI]

The heat capacity laser concept is extended to systems in which the heat capacity lasing media is a liquid. The laser active liquid is circulated from a reservoir (where the bulk of the media and hence waste heat resides) through a channel so configured for both optical pumping of the media for gain and for light amplification from the resulting gain.

Comaskey, Brian J. (Walnut Creek, CA); Scheibner, Karl F. (Tracy, CA); Ault, Earl R. (Livermore, CA)

2007-05-01T23:59:59.000Z

458

Heat Transfer Guest Editorial  

E-Print Network [OSTI]

Journal of Heat Transfer Guest Editorial We are indeed delighted in bringing out this special issue was showcased in diverse areas such as traditional heat and mass transfer, lab-on-chip, sensors, biomedical applica- tions, micromixers, fuel cells, and microdevices. Selected papers in the field of heat transfer

Kandlikar, Satish

459

Acoustic Heating Peter Ulmschneider  

E-Print Network [OSTI]

Acoustic Heating Peter Ulmschneider lnstitut fiir Theoretische Astrophysik der Universitat waves are a viable and prevalent heating mechanism both in early- and in late-type stars. Acoustic heating appears to be a dominant mechanism for situations where magnetic fields are weak or absent

Ulmschneider, Peter

460

Ammoniated salt heat pump  

SciTech Connect (OSTI)

A thermochemical heat pump/energy storage system using liquid ammoniate salts is described. The system, which can be used for space heating or cooling, provides energy storage for both functions. The bulk of the energy is stored as chemical energy and thus can be stored indefinitely. The system is well suited to use with a solar energy source or industrial waste heat.

Haas, W.R.; Jaeger, F.J.; Giordano, T.J.

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "heating season performance" 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.


461

Pioneering Heat Pump Project  

Broader source: Energy.gov [DOE]

Project objectives: To install and monitor an innovative WaterFurnace geothermal system that is technologically advanced and evolving; To generate hot water heating from a heat pump that uses non-ozone depleting refrigerant CO2. To demonstrate the energy efficiency of this system ground source heat pump system.

462

Cold Climates Heat Pump Design Optimization  

SciTech Connect (OSTI)

Heat pumps provide an efficient heating method; however they suffer from sever capacity and performance degradation at low ambient conditions. This has deterred market penetration in cold climates. There is a continuing effort to find an efficient air source cold climate heat pump that maintains acceptable capacity and performance at low ambient conditions. Systematic optimization techniques provide a reliable approach for the design of such systems. This paper presents a step-by-step approach for the design optimization of cold climate heat pumps. We first start by describing the optimization problem: objective function, constraints, and design space. Then we illustrate how to perform this design optimization using an open source publically available optimization toolbox. The response of the heat pump design was evaluated using a validated component based vapor compression model. This model was treated as a black box model within the optimization framework. Optimum designs for different system configurations are presented. These optimum results were further analyzed to understand the performance tradeoff and selection criteria. The paper ends with a discussion on the use of systematic optimization for the cold climate heat pump design.

Abdelaziz, Omar [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL

2012-01-01T23:59:59.000Z

463

A GUIDE TO FUEL PERFORMANCE  

SciTech Connect (OSTI)

Heating oil, as its name implies, is intended for end use heating consumption as its primary application. But its identity in reference name and actual chemical properties may vary based on a number of factors. By name, heating oil is sometimes referred to as gas oil, diesel, No. 2 distillate (middle distillate), or light heating oil. Kerosene, also used as a burner fuel, is a No. 1 distillate. Due to the higher heat content and competitive price in most markets, No. 2 heating oil is primarily used in modern, pressure-atomized burners. Using No. 1 oil for heating has the advantages of better cold-flow properties, lower emissions, and better storage properties. Because it is not nearly as abundant in supply, it is often markedly more expensive than No. 2 heating oil. Given the advanced, low-firing rate burners in use today, the objective is for the fuel to be compatible and achieve combustion performance at the highest achievable efficiency of the heating systems--with minimal service requirements. Among the Oil heat industry's top priorities are improving reliability and reducing service costs associated with fuel performance. Poor fuel quality, fuel degradation, and contamination can cause burner shut-downs resulting in ''no-heat'' calls. Many of these unscheduled service calls are preventable with routine inspection of the fuel and the tank. This manual focuses on No. 2 heating oil--its performance, properties, sampling and testing. Its purpose is to provide the marketer, service manager and technician with the proper guidelines for inspecting the product, maintaining good fuel quality, and the best practices for proper storage. Up-to-date information is also provided on commercially available fuel additives, their appropriate use and limitations.

LITZKE,W.

2004-08-01T23:59:59.000Z

464

Heat transfer studies, quarterly report  

SciTech Connect (OSTI)

Drying in subresidually-saturated systems at elevated temperatures has been studied for two different operating conditions. One condition started with flowing nitrogen gas through the test section and simultaneously heating up the porous medium at the same time (denoted in what follows as the ``transient heating case``). The other condition started initially with heating up the porous medium with no flow, and then running the nitrogen gas flow through the test section after a steady-state temperature distribution had been reached (denoted in what follows as the ``steady heating case``). A 90{degrees}C isothermal boundary condition was set on the aluminum wall. An average of 9% discrepancy in the mass balance calculation compared to the digital balance measurement has been found in the transient heating case. An average of 4.3% discrepancy in the mass balance calculation compared to the digital balance measurement has been found after the nitrogen gas flowed through test section for the steady heating case. A large discrepancy has also been found before the nitrogen gas admitted to the test section. This is because some of subresidual water in the test section has been drained out from the bottom due to the gravity effect and the strong convection flow in the porous medium before the nitrogen gas is admitted. This discrepancy may be reduced by closing the end tube at bottom before the nitrogen gas is admitted to the test section. The drying characteristics of this system are reported. A theoretical study has also been initiated in an attempt to supplement the experimental results, and this system is described in the report. A one-dimensional transient system is assumed in which a two-component (condensable and noncondensable) gas mixture flows through a porous medium with evaporation. The numerical calculation will be performed in the future work to compare to the experimental results.

Boehm, R.; Chen, Y.T.; Sathappan, A.K.

1996-01-19T23:59:59.000Z

465

Home Heating | Department of Energy  

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

Home Heating Everything you need to know about home heating, including how heating systems work, the different types on the market and proper maintenance. Read more Thermostats...

466

Water Heating | Department of Energy  

Energy Savers [EERE]

Energy Saver Water Heating Water Heating Infographic: Water Heaters 101 Infographic: Water Heaters 101 Everything you need to know about saving money on water heating costs....

467

A PASSIVE SOLAR HEATING SYSTEM COMBINED WITH A HEATPUMP AND A LONG TERM HEAT STORAGE  

Science Journals Connector (OSTI)

ABSTRACT This paper describes the design and the first preliminary performance results of a sunspace attached to an existent building, combined with a heatpump and a long term heat storage. The aim of the project is to study the possibility of storing the excess heat of the passive system in a low temperature storage, which is used as cold source for a heatpump. The advantages of the presented system are that the energy flows in the passive solar system can be controlled and that a rather high solar fraction can be obtained (around .7 to .8 in the climate of Ispra). KEYWORDS Passive solar energy, heat pump, heat storage

D. van Hattem; R. Colombo; P. Actis-Dato

1988-01-01T23:59:59.000Z

468

Field Monitoring Protocol: Mini-Split Heat Pumps  

SciTech Connect (OSTI)

The report provides a detailed method for accurately measuring and monitoring performance of a residential Mini-Split Heat Pump. It will be used in high-performance retrofit applications, and as part of DOE's Building America residential research program.

Christensen, D.; Fang, X.; Tomerlin, J.; Winkler, J.; Hancock, E.

2011-03-01T23:59:59.000Z

469

Bering Sea Chinook Salmon Seasonal Bycatch Report (includes CDQ)  

E-Print Network [OSTI]

101 IPA Season Total Catch Allocation Remaining Allocation % Taken Last Week Catch A 2,153 6,748 4,595 32% 0 B 5 4,024 4,019 0% 5 Total 2,158 10,772 8,614 20% 5 BS Chinook Salmon AFA COOP 102 IPA Season 0 0% 0 BS Chinook Salmon AFA COOP 103 IPA Season Total Catch Allocation Remaining Allocation % Taken

470

Bering Sea Chinook Salmon Seasonal Bycatch Report (includes CDQ)  

E-Print Network [OSTI]

101 IPA Season Total Catch Allocation Remaining Allocation % Taken Last Week Catch A 0 6,748 6,748 0% 0 B 0 4,024 4,024 0% 0 Total 0 10,772 10,772 0% 0 BS Chinook Salmon AFA COOP 102 IPA Season Total BS Chinook Salmon AFA COOP 103 IPA Season Total Catch Allocation Remaining Allocation % Taken Last

471

It Just Tastes Better When It's In Season  

E-Print Network [OSTI]

i IT JUST TASTES BETTER WHEN IT?S IN SEASON A Dissertation by LAURA NICOLA THOMAS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfilment of the requirements for the degree of DOCTOR... OF PHILOSOPHY May 2012 Major Subject: Nutrition ii It Just Tastes Better When It?s in Season Copyright 2012 Laura Nicola Thomas iii IT JUST TASTES BETTER WHEN IT?S IN SEASON A Dissertation...

Thomas, Laura

2012-07-16T23:59:59.000Z

472

BPA revises policy for managing seasonal power oversupply  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

y-for-managing-seasonal-power-oversupply Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us Projects & Initiatives Expand Projects &...

473

Measured Performance Signature Method  

E-Print Network [OSTI]

information for adaptive on-line optimum dispatch, equipment performance monitoring, or for conducting system "what if' scenarios. The MPS is a very useful technique which may be applied to Acceptance Testing Monitoring and Operations Optimization... performance signature, may be determined from on-line measurements, and corrected to a specified reference. This procedure also provides information for adaptive on-line optimum dispatch, incremental plant heat rate data for centralized system dispatch...

Ahner, D. J.

474

Active microchannel heat exchanger  

DOE Patents [OSTI]

The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

Tonkovich, Anna Lee Y. (Pasco, WA) [Pasco, WA; Roberts, Gary L. (West Richland, WA) [West Richland, WA; Call, Charles J. (Pasco, WA) [Pasco, WA; Wegeng, Robert S. (Richland, WA) [Richland, WA; Wang, Yong (Richland, WA) [Richland, WA

2001-01-01T23:59:59.000Z

475

Nanofluid heat capacities  

Science Journals Connector (OSTI)

Significant increases in the heat capacity of heat transfer fluids are needed not only to reduce the costs of liquid heating and cooling processes but also to bring clean energy producing technologies like concentrating solar power (CSP) to price parity with conventional energy generation. It has been postulated that nanofluids could have higher heat capacities than conventional fluids. In this work nano- and micron-sized particles were added to five base fluids (poly-? olefin mineral oil ethylene glycol a mixture of water and ethylene glycol and calcium nitrate tetrahydrate) and the resulting heat capacities were measured and compared with those of the neat base fluids and the weighted average of the heat capacities of the components. The particles used were inert metals and metal oxides that did not undergo any phase transitions over the temperature range studied. In the nanofluids studied here we found no increase in heat capacity upon the addition of the particles larger than the experimental error.

Anne K. Starace; Judith C. Gomez; Jun Wang; Sulolit Pradhan; Greg C. Glatzmaier

2011-01-01T23:59:59.000Z

476

A model for improvement of water heating heat exchanger designs for residential heat pump water heaters.  

E-Print Network [OSTI]

??Heat pump water heaters are a promising technology to reduce energy use and greenhouse gas emissions. A key component is the water heating heat exchanger.… (more)

Weerawoot, Arunwattana

2010-01-01T23:59:59.000Z

477

Replacing Resistance Heating with Mini-Split Heat Pumps, Sharon, Connecticut (Fact Sheet)  

SciTech Connect (OSTI)

Mini-split heat pumps can provide space heating and cooling in many climates and are relatively affordable. These and other features make them potentially suitable for retrofitting into multifamily buildings in cold climates to replace electric resistance heating or other outmoded heating systems. This report investigates the suitability of mini-split heat pumps for multifamily retrofits. Various technical and regulatory barriers are discussed and modeling was performed to compare long-term costs of substituting mini-splits for a variety of other heating and cooling options. A number of utility programs have retrofit mini-splits in both single family and multifamily residences. Two such multifamily programs are discussed in detail.

Not Available

2014-05-01T23:59:59.000Z

478

Technical evaluation of a solar heating system having conventional hydronic solar collectors and a radiant panel slab. Final report  

SciTech Connect (OSTI)

A simple innovative solar heating design (Solar Option One) using conventional hydronic solar collectors and a radiant panel slab was constructed. An objective of hybrid solar design is to combine the relative advantages of active and passive design approaches while minimizing their respective disadvantages. A test house using the Solar Option One heating system was experimentally monitored to determine its energy based performance during the 1982-83 heating season. The test residence is located in Lyndonville, Vermont, an area which has a characteristically cold and cloudy climate. The two story residence has a floor area of about 1400 square feet and is constructed on a 720 square foot 5.5 inch thick floor slab. A 24 inch packed gravel bed is located beneath the slab and the slab-gravel bed is insulated by two inches of polystyrene insulation. The test building is of frame construction and uses insulation levels which have become commonplace throughout the country. The structure would not fall into the superinsulated category but was tightly constructed so as to have a low infiltration level. The building is sun-tempered in that windows were concentrated somewhat on the South side and all but avoided on the North. A solar greenhouse on the South side of the building was closed off from the structure permanently throughout the testing so as to better observe the solar heating invention without confounding variables. The monitoring equipment generated an internal gain of about 17,000 BTUs per day, roughly the equivalent of occupancy by two persons. A full description of the experimental testing program is given. System efficiency and performance are reported.

Starr, R.J.

1984-04-01T23:59:59.000Z

479

Seasonal thermal signatures of heat transfer by water exchange in an underground vault  

Science Journals Connector (OSTI)

......also to the long-term temperature...underground waste storage and contaminant...underground nuclear waste storage sites is...2000), the long-term impact and...Concerning the long-term temperature...underground waste storage, underlying......

Frédéric Perrier; Pierre Morat; Toshio Yoshino; Osam Sano; Hisashi Utada; Olivier Gensane; Jean-Louis Le Mouël

2004-07-01T23:59:59.000Z

480

ARTERIAL PERFORMANCE MEASUREMENT WITH WIRELESS1 MAGNETIC SENSORS2  

E-Print Network [OSTI]

base signal timings on11 these meager studies, which hide daily, seasonal, weather, event and incident counts to calculate the21 most basic performance metrics, such as delay. The ATTS system appears

Varaiya, Pravin

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481

Four Seasons Windpower, LLC | Open Energy Information  

Open Energy Info (EERE)

Windpower, LLC Windpower, LLC Jump to: navigation, search Name Four Seasons Windpower, LLC Address 1697 Wilbur Road Place Medina, Ohio Zip 44256 Sector Solar, Wind energy Product Retail product sales and distribution Phone number 866-412-8346 Website http://www.fswindpower.com Coordinates 41.169146°, -81.7476779° 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":41.169146,"lon":-81.7476779,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

482

Tracing The Largest Seasonal Migration on Earth  

E-Print Network [OSTI]

It is estimated that over 3.6 billion passengers are travelling during the Chinese Spring Festival travel season. They leave their working cities and return their hometowns to enjoy annual family time, and back to cities after the holiday. In this study, with the massive location-based data collected from millions of smartphone users, we propose a novel method to trace the migration flow and explore the migration patterns of Chinese people. From the temporal perspective, we explore the migration trend over time during a 34-days period, about half a month before and after the Spring Festival. From the spatial perspective, the migration directions and routes are estimated and quantified, and the migration flow is visualized. The spatial range of influence of developed regions could be reflected with the destinations of migration, the migration destinations and originations have obvious characteristic of geographical proximity.

Wang, Xianwen; Mao, Wenli; Hu, Zhigang; Gu,