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Estimates of Refrigerator Loads in Public Housing Based on Metered Consumption Data

Description: The New York Power Authority (NYPA), the New York City Housing Authority (NYCHA), and the U.S. Departments of Housing and Urban Development (HUD) and Energy (DOE) have joined in a project to replace refrigerators in New York City public housing with new, highly energy-efficient models. This project laid the ground work for the Consortium for Energy Efficiency (CEE) and DOE to enable housing authorities throughout the United States to bulk-purchase energy-efficient appliances. DOE helped develop and plan the program through the ENERGY STAR@ Partnerships program conducted by its Pacific Nofiwest National Laboratory (PNNL). PNNL was subsequently asked to conduct the savings evahations for 1996 and 1997. PNNL designed the metering protocol and occupant survey, supplied and calibrated the metering equipment, and managed and analyzed the data. The 1996 metering study of refrigerator energy usage in New York City public housing (Pratt and Miller 1997) established the need and justification for a regression-model-based approach to an energy savings estimate. The need originated in logistical difficulties associated with sampling the population and pen?orming a stratified analysis. Commonly, refrigerators[a) with high representation in the popula- tion were missed in the sampling schedule, leaving significant holes in the sample and difficulties for the stratified anrdysis. The just{jfcation was found in the fact that strata (distinct groups of identical refrigerators) were not statistically distinct in terms of their label ratio (ratio of metered consumption to label rating). This finding suggested a general regression model could be used to represent the consumption of all refrigerators in the population. In 1996 a simple two-coefficient regression model, a function of only the refrigerator label rating, was developed and used to represent the existing population of refrigerators. A key concept used in the 1997 study grew from findings in a small number of apartments metered in 1996 with a ...
Date: September 11, 1998
Creator: Miller, JD & Pratt, RG
Partner: UNT Libraries Government Documents Department

Magnetic refrigeration: the promise and the problems

Description: Magnetic refrigeration uses the temperature- and field-dependence of the entropy of some magnetic materials to accomplish cooling. Because of the intrinsically high efficiency of the magnetization and demagnetization process and because of the potential for excellent heat transfer between solids and fluids, magnetic refrigerators promise to have higher efficiency than existing gas-cycle refrigerators. Many ground-based and space-based applications could benefit significantly from the cost savings implied by higher efficiency. Other attributes of these devices are high reliability and low volume and mass per unit cooling power. The development of these refrigerators is underway at several places around the world, including the Los Alamos National Laboratory. The progress to date has been encouraging but some problems have been clearly identified. The arguments for high efficiency and the problems that will need to be solved to achieve this goal are discussed.
Date: January 1, 1984
Creator: Barclay, J.A.
Partner: UNT Libraries Government Documents Department

Energy-efficient appliance labeling in China: Lessons for successful labeling programs in varied markets

Description: Appliance ownership and production has increased dramatically in China in the past two decades. From extremely low levels in 1980, China's appliance industry has become one of the largest in the world, with sales topping U.S. $14.4 billion in 2000. In 1981, less than 1 percent of urban Chinese households owned a refrigerator; by 1998, that number had increased to over 75 percent. This dramatic increase in sales and ownership leads to an excellent opportunity to impact energy consumption in China by affecting the energy efficiency of appliances being bought and sold. In general, Chinese consumers value energy efficiency and are knowledgeable about the operating costs of major appliances. However, the Chinese marketplace does not provide information that consumers trust about the energy consumption of specific products. Thus, several interdependent organizations have emerged in China to provide information and market supports for energy efficiency. This paper describes the appliance market in China and the evolution of its standards and labeling programs and the agencies that implement them. It discusses the authors' work with these organizations in developing energy efficiency criteria and supporting an energy efficiency endorsement labeling program in China. It describes how the authors have used their experience with ENERGY STAR{reg_sign} and other programs in the U.S. to work with China to develop a successful program specific to Chinese conditions, with a particular emphasis on refrigerators. It then gives the author's market assessment of the Chinese refrigerator market and recommendations for a successful labeling program and transferable lessons for developing energy efficiency labeling programs in varied markets. This paper is based on the authors' market research, their support in setting energy efficiency criteria in China, interviews with Chinese manufacturers, retailers, and sales staff, and the development and implementation of labeling strategies and promotion in China.
Date: August 20, 2002
Creator: Lin, Jiang; Townend, Jeanne; Fridley, David; McNeil, Gary; Silva, Tony & Clark, Robin
Partner: UNT Libraries Government Documents Department

Japanese Refrigerators Field Testing.

Description: Residential refrigerators consume the equivalent of 1700 megawatts (MW) of baseload power in the Bonneville Power Administration (BPA) service area. Japanese manufacturers have designed refrigerator units that appear more energy efficient than some currently available American models. This report summarizes preliminary findings from field testing of 12 refrigerators of Japanese manufacture to evaluate annual kilowatt hour (kWh) use during actual operation. The units have also undergone laboratory testing sponsored by BPA at ETL Testing Laboratories, Inc. in Cortland, New York. A final report of the project -- due at the end of 1989 -- will correlate in detail the results of field and laboratory tests in comparison to performance ratings determined by the manufacturer.
Date: March 1, 1989
Creator: Lou, Albert T.
Partner: UNT Libraries Government Documents Department

Analysis of magnetic refrigerators with external regeneration

Description: The central idea of the magnetic refrigeration systems analyzed in this paper is that of a MR having a regenerator composed of an integral number of separate stages but having only a single magnetic stage. In principle, each stage is thermally isolated from the others, but the stages are accessed by a manifold and valve system which allows gas to flow between the MM and the individual stages. The concept therefore is distinctly unlike that of the unusual continuous regenerator of gas refrigerators. Although a small amount of gas in the manifold is responsible for the actual transfer of heat between elements of the REGMR, it is clear from the cycle description in the caption of Fig. 1 that the fixed mass of the MM is analogous to a fixed mass of a working fluid in a gas refrigerator or engine. Both, in effect, are carried thermally through all parts of their respective systems.
Date: January 1, 1986
Creator: Overton, W.C. Jr. & Barclay, J.A.
Partner: UNT Libraries Government Documents Department

Relief valve sizing for the sup 3 He recirculation system of the MP-9 polarized target

Description: This report contains pressure safety analyses for the relief valving of the {sup 3}He pump system, as distinct from the dilution refrigerator (DR). However, in a few instances it has been convenient to include here some aspects of the interaction between the DR and the gas loop proper. The more localized safety aspects of certain elements of the DR, such as the vacuum jacket and window, the Still, and the Phase Separator, will be addressed in a separate analysis.
Date: August 21, 1989
Creator: Hill, D.
Partner: UNT Libraries Government Documents Department

Magnetic refrigeration for spacecraft systems

Description: Magnetic refrigerators, i.e., those that use the magnetocaloric effect of a magnetic working material in a thermodynamic cycle, offer potentially reliable, and efficient refrigeration over a variety of temperature ranges and cooling powers. A descriptive analysis of magnetic refrigeration systems is performed with particular emphasis on more efficient infrared detector cooling. Three types of magnetic refrigerator designs are introduced to illustrate some of the possibilities.
Date: January 1, 1981
Creator: Barclay, J.A.
Partner: UNT Libraries Government Documents Department

Experience with small turbomachinery in a 400 watt refrigerator

Description: A refrigerator similar to one of the Fermilab Tevatron satellites was reconfigured to use turbomachinery instead of the reciprocating equipment typical of the installations. A Sulzer dry turboexpander, Creare wet turboexpander, and IHI centrifugal cold compressor have been installed and operated for about 8000 hours. Experience was gained both with the rotating machinery and with the refrigerator itself as it interfaced with the load. Equipment was set up to regulate in the same manner as the reciprocating devices had. Heat load and operating mode were adjusted and evaluations made regarding the behavior of the devices. Individual equipment performance is described as well as system behavior and overall integration of the machinery. In particular, attention is paid to the Creare wet turboexpander. This device is operated for the first time as part of a full scale refrigeration system, testing not only its performance at the design point but also its off design characteristics and behavior in transient situations.
Date: September 1, 1996
Creator: Fuerst, J.D.
Partner: UNT Libraries Government Documents Department

Energy use of icemaking in domestic refrigerators

Description: This study was designed to develop and test a procedure to measure the electrical consumption of ice making in domestic refrigerators. The Department of Energy (DOE) test procedure was modified to include the energy used for icemaking in conventional refrigerators and those equipped with automatic icemakers. The procedure assumed that 500 grams of ice would be produced daily. Using the new test procedure and the existing DOE test (as a benchmark), four refrigerators equipped with automatic icemakers were tested for ice-making energy use. With the revised test, gross electricity consumption increased about 10% (100 kWh/yr) due to automatic icemaking but about 5% (55 kWh/yr) could be attributed to the special features of the automatic icemaker. The test also confirmed the feasibility of establishing procedures for measuring energy use of specific loads and other activities related to domestic refrigerators. Field testing and subsequent retesting revealed a 14% increase in energy use.
Date: February 1, 1996
Creator: Meier, A. & Martinez, M.S.
Partner: UNT Libraries Government Documents Department

Initial performance of upgraded Tevatron cryogenic systems

Description: Fermilab began operating a re-designed satellite refrigerator systems in November 1993. Upgrades were installed to operate the Tevatron at a magnet temperature of 3.5 K, approximately 1K lower than the original design. Refrigerator upgrades included new valve boxes, larger reciprocating expanders, the installation of cold vapor compressors, new sub-atmospheric instrumentation and an entirely new distributed controls system. Cryogenic system reliability data for Colliding Physics Run 1B is presented emphasizing a failure analysis for each aspect of the upgrade. Comparison to data for Colliding Physics Run 1A (previous to upgrade) is presented to show the impact of a major system overhaul. New operational problems and their solutions are presented in detail.
Date: September 1, 1996
Creator: Norris, B.L.
Partner: UNT Libraries Government Documents Department

Experimental and cost analyses of a one kilowatt-hour/day domestic refrigerator-freezer

Description: Over the past ten years, government regulations for energy standards, coupled with the utility industry`s promotion of energy-efficient appliances, have prompted appliance manufacturers to reduce energy consumption in refrigerator-freezers by approximately 40%. Global concerns over ozone depletion have also required the appliance industry to eliminate CFC-12 and CFC-11 while concurrently improving energy efficiency to reduce greenhouse emissions. In response to expected future regulations that will be more stringent, several design options were investigated for improving the energy efficiency of a conventionally designed, domestic refrigerator-freezer. The options, such as cabinet and door insulation improvements and a high-efficiency compressor were incorporated into a prototype refrigerator-freezer cabinet and refrigeration system. Baseline energy consumption of the original 1996 production refrigerator-freezer, along with cabinet heat load and compressor calorimeter test results, were extensively documented to provide a firm basis for experimentally measured energy savings. The goal for the project was to achieve an energy consumption that is 50% below in 1993 National Appliance Energy Conservation Act (NAECA) standard for 20 ft{sup 3} (570 l) units. Based on discussions with manufacturers to determine the most promising energy-saving options, a laboratory prototype was fabricated and tested to experimentally verify the energy consumption of a unit with vacuum insulation around the freezer, increased door thicknesses, a high-efficiency compressor, a low wattage condenser fan, a larger counterflow evaporator, and adaptive defrost control.
Date: May 1, 1997
Creator: Vineyard, E.A. & Sand, J.R.
Partner: UNT Libraries Government Documents Department

Thermoacoustic engines and refrigerators

Description: This report is a transcript of a practice lecture given in preparation for a review lecture on the operation of thermoacoustic engines and refrigerators. The author begins by a brief review of the thermodynamic principles underlying the operation of thermoacoustic engines and refrigerators. Remember from thermodynamics class that there are two kinds of heat engines, the heat engine or the prime mover which produces work from heat, and the refrigerator or heat pump that uses work to pump heat. The device operates between two thermal reservoirs at temperatures T{sub hot} and T{sub cold}. In the heat engine, heat flows into the device from the reservoir at T{sub hot}, produces work, and delivers waste heat into the reservoir at T{sub cold}. In the refrigerator, work flows into the device, lifting heat Q{sub cold} from reservoir at T{sub cold} and rejecting waste heat into the reservoir at T{sub hot}.
Date: December 31, 1996
Creator: Swift, G.
Partner: UNT Libraries Government Documents Department

Suppression of acoustic streaming in tapered pulse tubes

Description: In a pulse tube cryocooler, the gas in the pulse tube can be thought of as an insulating piston, transmitting pressure and velocity from the cold heat exchanger to the hot end of the pulse tube. Unfortunately, convective heat transfer can carry heat from the hot end to the cold end and reduce the net cooling power. Here, the authors discuss one driver of such convection: steady acoustic streaming as generated by interactions between the boundary and the oscillating pressure, velocity, and temperature. Using a perturbation method, they have derived an analytical expression for the streaming in a tapered pulse tube with axially varying mean temperature in the acoustic boundary layer limit. The calculations showed that the streaming depends strongly on the taper angle, the ratio of velocity and pressure amplitudes, and the phase between the velocity and pressure, but it depends only weakly on the mean temperature profile and is independent of the overall oscillatory amplitude. With the appropriate tapering of the tube, streaming can be eliminated for a particular operating condition. Experimentally, the authors have demonstrated that an orifice pulse tube cryocooler with the calculated zero-streaming taper has more cooling power than one with either a cylindrical tube or a tapered pulse tube with twice the optimum taper angle.
Date: December 31, 1998
Creator: Olson, J.R. & Swift, G.W.
Partner: UNT Libraries Government Documents Department

Aging of polyurethane foam insulation in simulated refrigerator walls

Description: Laboratory data are presented on the thermal conductivity of polyurethane foam insulation in composite test panels that simulate refrigerator walls. The test panels consisted of a steel skin, an ABS plastic liner, and a polyurethane foam core. Foam cores were produced with three different blowing agents (CFC-11, HCFC-141b, and a HCFC-142/22 blend). Periodic thermal measurements have been made on these panels over a three and one half year period in an effort to detect aging processes. Data obtained on foam encased in the panels were compared with measurements on thin foam slices that were removed from similar panels. The data show that the encapsulation of the foam in the solid boundary materials greatly reduces the aging rate. The plan is presented for a follow-on project that is being conducted on the aging of foams blown with HCFC-141b, HFC-134a, HFC-245fa, and cyclopentane.
Date: October 1997
Creator: Wilkes, K. E.; Yarbrough, D. W. & Weaver, F. J.
Partner: UNT Libraries Government Documents Department

Super-Efficient Refrigerator Program (SERP) evaluation volume 2: Preliminary impact and market transformation assessment

Description: The Super Efficient Refrigerator Program (SERP) is a collaborative utility program intended to transform the market for energy-efficient and environmentally friendly refrigerators. It is one of the first examples of a large-scale {open_quotes}market transformation{close_quotes} energy efficiency program. This report documents the preliminary impact and market transformation evaluation of SERP ({open_quotes}the Program{close_quotes}). Pacific Northwest National Laboratory (PNNL) conducted this evaluation for the U.S. Department of Energy. This study focuses on the preliminary impact evaluation and market transformation assessment, but also presents limited process evaluation information. It is based on interviews with refrigerator dealers and manufacturers, interviews with utility participants, industry data, and information from the Program administrators. Results from this study complement those from prior process evaluation also conducted by PNNL. 42 refs., 5 figs., 4 tabs.
Date: August 1, 1996
Creator: Lee, A.D. & Conger, R.L.
Partner: UNT Libraries Government Documents Department

Performance of a tapered pulse tube

Description: In a well instrumented pulse tube refrigerator having 1,500 W of cooling power at 125 K, the authors have measured the figure of merit of a tapered pulse tube at several operating points. At operating points near the operating point for which the taper was designed, the figure of merit is 0.96. This is close to the theoretical optimum figure of merit 0.97 calculated for this pulse tube considering only two loss mechanisms: heat conduction in the metal pulse tube wall and ordinary thermoacoustic heat transport in the gas within a few thermal penetration depths of the wall. At operating points farther from the design operating point, the measured figure of merit is much lower, as streaming driven convection adds a third loss mechanism.
Date: February 1, 1998
Creator: Swift, G.; Allen, M. & Woolan, J.J.
Partner: UNT Libraries Government Documents Department

DOE/AHAM advanced refrigerator technology development project

Description: As part of the effort to improve residential energy efficiency and reduce greenhouse emissions from power plants, several design options were investigated for improving the energy efficiency of a conventionally designed domestic refrigerator-freezer. The program goal was to reduce the energy consumption of a 20-ft{sup 3} (570-L) top-mount refrigerator-freeze to 1.00 kWh/d, a 50% reduction from the 1993 National Appliance Energy Conservation Act (NAECA) standard. The options--such as improved cabinet and door insulation, a high-efficiency compressor, a low-wattage fan, a large counterflow evaporator, and adaptive defrost control--were incorporated into prototype refrigerator-freezer cabinets and refrigeration systems. The refrigerant HFC-134a was used as a replacement for CFC-12. The baseline energy performance of the production refrigerator-freezers, along with cabinet heat load and compressor calorimeter test results, were extensively documented to provide a firm basis for experimentally measured energy savings. The project consisted of three main phases: (1) an evaluation of energy-efficient design options using computer simulation models and experimental testing, (2) design and testing of an initial prototype unit, and (3) energy and economic analyses of a final prototype. The final prototype achieved an energy consumption level of 0.93 kWh/d--an improvement of 45% over the baseline unit and 54% over the 1993 NAECA standard for 20-fg{sup 3} (570-L) units. The manufacturer`s cost for those improvements was estimated at $134; assuming that cost is doubled for the consumer, it would take about 11.4 years to pay for the design changes. Since the payback period was thought to be unfeasible, a second, more cost-effective design was also tested. Its energy consumption level was 1.16 kWh/d, a 42% energy savings, at a manufacturer`s cost increase of $53. Again assuming a 100% markup, the payback for this unit would be 6.6 years.
Date: March 1, 1997
Creator: Vineyard, E.A.; Sand, J.R.; Rice, C.K.; Linkous, R.L.; Hardin, C.V. & Bohman, R.H.
Partner: UNT Libraries Government Documents Department

Aging of polyurethane insulation foamed with second- and third-generation blowing agents

Description: Results are presented on two studies of the effect of aging on the apparent thermal conductivity of polyurethane foam insulation for refrigerators. Both studies are cooperative projects between the Oak Ridge National Laboratory and the Appliance Research Consortium. The first study has been ongoing for four years and involves evaluation of second generation blowing agents: HCFC-141b and HCFC-142/22 blend with CFC-11 for comparison. The second study has recently started and involves third generation blowing agents: HFC-134a, HFC-245fa. and cyclopentane with HCFC-141b for comparison. Both studies consist of periodic thermal measurements on panels made with solid steel and/or plastic skins and a core of foam to simulate refrigerator walls, and measurements on thin slices with cut faces to characterize the core foam. Laboratory data are presented on four years of aging of panels containing second generation blowing agents. Preliminary data are presented for the third generation blowing agents. The data on panels are compared with predictions of computer models of foam aging.
Date: May 1998
Creator: Wilkes, K. E.; Gabbard, W. A. & Weaver, F. J.
Partner: UNT Libraries Government Documents Department

New York Power Authority/New York City Housing Authority refrigerator replacement program, first program year evaluation. Final report

Description: Acting as an energy services provider, the New York Power Authority (NYPA) has initiated a long-term project through which 20,000 refrigerators per year will be replaced with the most energy-efficient units possible in apartments managed by the New York City Housing Authority (NYCHA). Using bulk purchasing as an incentive to appliance manufacturers to produce energy-efficient refrigerators suitable for use in apartments, replaced in the first year of the program, which ended in December 1996. These units, kWh per year. Savings were determined by field testing and laboratory testing of 220 existing refrigerators and 56 newly-installed units. In the next program year, a 15.0-cubic-foot Maytag refrigerator, newly-designed in response to bulk purchasing incentives, is being installed. The new unit has a label rating of 437 kWh per year, 31 percent better than 1993 energy standards. Old refrigerators removed from apartments are {open_quotes}demanufactured{close_quotes} in an environmentally-appropriate way and both metals and refrigerants are recovered for reuse.
Date: August 1, 1997
Creator: Kinney, L.F.; Lewis, G.; Pratt, R.G. & Miller, J.
Partner: UNT Libraries Government Documents Department