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Design and Installation Manual for Thermal Energy Storage, Second Edition

Description: The second addition is a substantial revision of the original work. A new chapter on latent heat storage, an appendix on units and conversions, and an index have been added. The purpose for this manual is to provide information on the design and installation of thermal energy storage in solar heating systems. It is intended for contractors, installers, solar system designers, engineers, architects, and manufacturers who intend to enter the solar energy business. The reader should have general knowledge of how solar heating systems operate and knowledge of construction methods and building codes. Knowledge of solar analysis methods such as f-chart, SOLCOST, DOE-1, or TRNSYS would be helpful. The information contained in the manual includes sizing storage, choosing a location for the storage device, and insulation requirements. Both air-based and liquid-based systems are covered with topics on designing rock beds, tank types, pump and fan selection, installation, costs, and operation and maintenance. Topics relevant to latent heat storage include properties of phase-change materials, sizing the storage unit, insulating the storage unit, available systems, and cost. Topics relevant to heating domestic water include safety, single- and dual-tank systems, domestic water heating with air- and liquid-based space heating systems, and stand alone domestic hot water systems. Several appendices present common problems with storage systems and their solutions, heat transfer fluid properties, economic insulation thickness, heat exchanger sizing, and sample specifications for heat exchangers, wooden rock bins, steel tanks, concrete tanks, and fiberglass-reinforced plastic tanks.
Date: January 1980
Creator: Cole, Roger Lynn; Nield, Kenneth J.; Rohde, Raymond R. & Wolosewicz, R. M.
Partner: UNT Libraries Government Documents Department

Argonne Solar Energy Program Annual Report: 1979

Description: This report describes the R&D work done at Argonne National Laboratory on solar energy technologies during the period October 1, 1978, to September 30, 1979. Technical areas included in the ANL solar program are solar energy collection, heating and cooling, thermal energy storage, ocean thermal energy conversion, photovoltaics, biomass conversion, satellite power systems, and solar liquid-metal MHD power systems.
Date: June 1980
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department

Argonne Solar Energy Program Annual Report: 1979

Description: This report describes the R&D work done at Argonne National Laboratory on solar energy technologies during the period October 1, 1978, to September 30, 1979. Technical areas included in the ANL solar program are solar energy collection, heating and cooling, thermal energy storage, ocean thermal energy conversion, photovoltaics, biomass conversion, satellite power systems, and solar liquid-metal MHD power systems.
Date: June 1980
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department

Comparison of Testing Methods for Latent-Heat-Storage Devices

Description: ASHRAE Standard 94-77, Method of Testing Thermal Storage Devices Based on Thermal Performance, was developed to allow manufacturers of thermal energy storage devices to compare their products in a meaningful way. When Standard 94-77 was used for thermal energy storage products based on latent heat storage, the Standard was found to be inadequate for comparison of these devices. Standard Project Committee SPC 94.1 was established to devise a Standard that would be adequate for comparing latent heat systems. The purpose of this report is to describe several alternatives to Standard 94-77 and discuss the advantages and disadvantages of each alternative. The discussion focuses on two proposed replacement standards and includes experimental results for each. The experimental results are from tests conducted on a PCM storage tank that uses sodium thiosulfate as the PCM and water as the heat transfer fluid. The experimental arrangement is discussed in detail.
Date: February 1983
Creator: Cole, Roger Lynn; Hull, J. R.; Lwin, Y. & Cha, Y. S.
Partner: UNT Libraries Government Documents Department

Natural Thermal Stratification in Tanks : Phase 1 Final Report

Description: This report describes how solar system tanks fail to stratify, a new solar system control strategy that allows stratification, a one-dimensional analytical model of thermally stratified tanks, experimental measurement of thermal stratification in tanks, correlation of experimental measurements with empirical constants in the analytical model, and a procedure for designing thermally stratified tanks. Failure to stratify is explained in terms of the critical Richardson number. The key to the new control strategy is to avoid a Richardson number that decreases during solar collection. The analytical model is an approximate solution based on assumptions that (1) the solution is a function of elevation and time, only, (2) plug flow exists, (3) flow rate is constant, (4) the cross-sectional areas of the tank and tank wall are constant, (5) there is a step change of inlet temperature, (6) there is heat transfer between the tank wall and the water, and (7) thermal losses from the tank are negligible. Empirical constants in the theory are determined by adjusting them until the best least-squares fit with experimental data is obtained and correlating the constants with the Fourier and Richardson numbers. The new control strategy allows tanks to stratify and reduces the average collector operating temperature by as much as 20/sup 0/C. The result is up to 20% improvement in system performance. The analytical model and correlation of its empirical constants allow system designers to select from several alternatives the tank configuration that provides the best stratification.
Date: February 1982
Creator: Cole, Roger Lynn & Bellinger, F. O.
Partner: UNT Libraries Government Documents Department

Development of a Low-Lift Chiller Controller and Simplified Precooling Control Algorithm - Final Report

Description: KGS Buildings LLC (KGS) and Pacific Northwest National Laboratory (PNNL) have developed a simplified control algorithm and prototype low-lift chiller controller suitable for model-predictive control in a demonstration project of low-lift cooling. Low-lift cooling is a highly efficient cooling strategy conceived to enable low or net-zero energy buildings. A low-lift cooling system consists of a high efficiency low-lift chiller, radiant cooling, thermal storage, and model-predictive control to pre-cool thermal storage overnight on an optimal cooling rate trajectory. We call the properly integrated and controlled combination of these elements a low-lift cooling system (LLCS). This document is the final report for that project.
Date: November 30, 2011
Creator: Gayeski, N.; Armstrong, Peter; Alvira, M.; Gagne, J. & Katipamula, Srinivas
Partner: UNT Libraries Government Documents Department

Analysis of Heat-Pipe Absorbers in Evacuated-Tube Solar Collectors

Description: Heat transfer in evacuated-tube solar collectors with heat-pipe absorbers is compared with that for similar collectors with flow-through absorbers. In systems that produce hot water or other heated fluids, the heat-pipe absorber suffers a heat transfer penalty compared with the flow-through absorber, but in many cases the penalty can be minimized by proper design at the heat-pipe condenser and system manifold. The heat transfer penalty decreases with decreasing collector heat loss coefficient, suggesting that evacuated tubes with optical concentration are more appropriate for use with heat pipes than evacuated or non-evacuated flat-plate collectors. When the solar collector is used to drive an absorption chiller, the heat-pipe absorber has better heat transfer characteristics than the flow-through absorbers.
Date: February 1986
Creator: Hull, John R.; Schertz, William W. & Allen, John W.
Partner: UNT Libraries Government Documents Department

Thermal energy storage for solar applications: an overview

Description: This report presents an overview of current technology and programs including some economic studies in low, intermediate, and high temperatre thermal energy storage for solar applications and an assessment of key problem areas. Previous studies of the economic role of storage for solar home heating and stand-alone electric plants are examined first and factors which affect the economics of storage are discussed. Next, the costs and storage capacities of representative sensible and latent heat storage materials are summarized. Various modes of operation are also presented for thermal storage by reversible chemical reactions, but this technology is at such an immature stage of development that its economic and technical potential are not clearly understood. Some new ideas in containers and heat exchangers are reviewed to illustrate possible innovative approaches to reducing storage costs. A more detailed examination is then made of reversible reaction storage, and gas-solid reactions are shown to have desirable attributes for solar energy storage. However, there are problems with heat transfer and heat exchanger for these systems that must be solved to make such systems more economically attractive. The DOE programs in thermal energy storage are reviewed in light of this review, and recommendations are made for future program directions which appear at this time to have the greatest potential impact on reducing technical and economic barriers to thermal storage utilization.
Date: March 1, 1979
Creator: Wyman, C.
Partner: UNT Libraries Government Documents Department

SERI Solar-Energy-Storage Program

Description: The SERI Solar Energy Storage Program is summarized. The program provides research, systems analysis, and assessments of thermal energy storage and transport in support of the Thermal Energy Storage Program of the DOE Division of Energy Storage Technology; emphasis is on thermal energy storage for solar thermal power and process heat applications and on thermal energy transport. Currently, research is in progress on direct-contact thermal energy storage and thermochemical energy storage and transport. In addition, SERI is directing the definition of new concepts for thermal energy storage and supporting research on thermal energy transport by sensible and latent heat media. SERI is performing systems analyses of thermal energy storage for solar thermal application and coordinating thermal energy storage activities for solar applications.
Date: August 1, 1981
Creator: Wyman, C.E.
Partner: UNT Libraries Government Documents Department

Cooling concept integration. Phase I final technical report, October 1, 1979-July 31, 1981. [For pre-engineered metal buildings]

Description: Before specific test prototypes were developed, six potential evaporative roof cooling configurations with alternative storage and heat transfer mechanisms were examined, and preliminary cost estimates were made. Each system uses a wet roof system which sprays or floods the roof, allowing evaporative heat transfer to the environment. Finite difference thermal network methods were used for the evaluation of the systems. Detailed results including charts of the hourly heat flows during particular days are presented, and the performance is summarized for Las Vegas. (LEW)
Date: August 19, 1981
Creator: Fraker, H.; Glennie, W. & Snyder, M.K.
Partner: UNT Libraries Government Documents Department

Computer modeling of thermal storage walls

Description: The modeling of the three-dimensional heat transfer characteristics of thermal storage walls and the effect of nonuniform irradiation is investigated. Depending on how much of the wall is irradiated, a small error in energy storage is introduced with the one-dimensional, uniform irradiation assumption. The results show that these assumptions, currently used in most passive design codes, are adequate to predict the thermal energy storage characteristics. However, the temperature distribution along the surface of the wall is much different when the nonuniform irradiation case is considered. The addition of a highly conductive metal cover on the front surface of the wall does not significantly improve the thermal energy storage characteristics of the wall when the wall is partially irradiated. A selective radiation coating reduces front losses and improves the energy storage capacity of the wall 9 to 13%.
Date: May 1, 1980
Creator: Connolly, J.M.; Bingham, C.E. & Ortega, J.K.E.
Partner: UNT Libraries Government Documents Department

Low-temperature thermal energy storage program annual operating plan

Description: The Low-Temperature Thermal Energy Storage (LTTES) Program operating plans for FY 1979 are described in terms of general program objectives and the technical activities being implemented to achieve these objectives. The program structure provides emphasis on several principal thrusts; namely, seasonal thermal storage, daily/short-term thermal storage, and recovery and reuse of waste heat. Fiscal data are summarized according to thrust area, individual efforts, and funding source.
Date: August 1, 1979
Creator: Eissenberg, D.M. & Hoffman, H.W.
Partner: UNT Libraries Government Documents Department

U.S. Department of Energy thermal energy storage research activities review: 1989 Proceedings

Description: Thermal Energy Storage (TES) offers the opportunity for the recovery and re-use of heat currently rejected to the ambient environment. Further, through the ability of TES to match an energy supply with a thermal energy demand, TES increases efficiencies of energy systems and improves capacity factors of power plants. The US Department of Energy has been the leader in TES research, development, and demonstration since recognition in 1976 of the need for fostering energy conservation as a component of the national energy budget. The federal program on TES R and D is the responsibility of the Office of Energy Storage and Distribution within the US Department of Energy (DOE). The overall program is organized into three program areas: diurnal--relating primarily to lower temperature heat for use in residential and commercial buildings on a daily cycle; industrial--relating primarily to higher temperature heat for use in industrial and utility processes on an hourly to daily cycle; seasonal--relating primarily to lower temperature heat or chill for use in residential complexes (central supply as for apartments or housing developments), commercial (light manufacturing, processing, or retail), and industrial (space conditioning) on a seasonal to annual cycle. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: March 1989
Creator: Hoffman, H. W. & Tomlinson, J. J.
Partner: UNT Libraries Government Documents Department

Model of direct contact heat transfer for latent heat energy storage

Description: Direct contact heat transfer is an attractive method to reduce the cost of heat exchange for latent heat thermal energy storage systems. However, current performance information is insufficient to allow an accurate appraisal of its economic and technical feasibility. In a direct contact heat transfer system, an immiscible fluid is bubbled through the storage media and heat is transferred between the phases as the droplets rise. An analytical model is presented for predicting the temperature of the rising droplets from information in the literature. The drop size is calculated from empirical correlations in the jetting formation region and rise velocity is characterized by a creeping-flow surface cell model which accounts for the hindering effects of neighboring droplets. The viscosity of the crystallizing solution in the rise velocity equation is approximated by an expression for concentrated suspensions, where the percentage of solids is taken as the percentage of crystallization. Dispersed phase holdup is predicted with the rise velocity. Calculation of the rate of heat transfer to the dispersed immiscible fluid droplets is based on three different internal hydrodynamic approximations: rigid, internally circulating, and wall-mixed spheres. The predictions of the circulating drop case agree reasonably well in the latent heat region with previous data on a similar system. However, because the model is also sensitive to the estimates used for drop size, continuous phase viscosity, and interfacial tension, the heat transfer mechanism cannot be conclusively identified, and experimental research is required to establish the validity of the model.
Date: May 1, 1980
Creator: Cease, M. E.
Partner: UNT Libraries Government Documents Department

Ground coupled solar heat pump research program in the United States

Description: The ground coupling research program funded by the Systems Development Division of the Office of Solar Applications of the US Department of Energy studies the use of the earth as a heat source/sink or storage element for solar heat pump space conditioning systems. The goal of this research program is to determine the feasibility of ground coupling, and if feasibility is confirmed, to create handbooks which facilitate widespread application of ground coupling. The research program is outlined and the research projects currently in progress and how they fit into the program are described. Progress toward the program goal is evaluated.
Date: January 1, 1980
Creator: Metz, P D
Partner: UNT Libraries Government Documents Department

Use of solid-state phase transitions for thermal energy storage. Final report, June 1, 1977--August 31, 1978

Description: A study has been carried out on the feasibility of using solid-state phase transitions for thermal energy storage. As part of this study a literature search was made to identify the most promising types of compounds and a synthesis program was carried out to prepare certain of these substances. In addition a large number of compounds for testing were obtained from commercial sources. All of the compounds were screened for transitions using a Perkin Elmer DSC-1B differential scanning calorimeter. From this program seven compounds were found that have transition energies from 20-30 cal/g in the temperatre range of 335-405 K. The most promising compound found is 5-norbornene-2,3-dicarboxylic acid anhydride having a transition of 22.6 cal/g at 366 K and an estimated cost of peparation of $0.40/lb..
Date: January 1, 1978
Creator: Leffler, A.J.; Myers, J. & Weinstein, D.
Partner: UNT Libraries Government Documents Department

Modeling for moving boundary problems

Description: The classical problems in partial differential equations involve solving an equation within a fixed spatial region. However, when attempting to model such phenomena as melting and freezing, we find that as time varies the region in which, e.g., material in the liquid phase is present, will also vary and must be determined. Such problems, for which the solution of a partial differential equation is sought in a region which is itself varying in an unknown manner, are referred to as moving boundary problems. The current state of the art of moving boundary problems as it applies to the storage of heat as latent heat is described.
Date: January 1, 1979
Creator: Solomon, A.D.
Partner: UNT Libraries Government Documents Department

MICRO-CHP System for Residential Applications

Description: This is the final report of progress under Phase I of a project to develop and commercialize a micro-CHP system for residential applications that provides electrical power, heating, and cooling for the home. This is the first phase of a three-phase effort in which the residential micro-CHP system will be designed (Phase I), developed and tested in the laboratory (Phase II); and further developed and field tested (Phase III). The project team consists of Advanced Mechanical Technology, Inc. (AMTI), responsible for system design and integration; Marathon Engine Systems, Inc. (MES), responsible for design of the engine-generator subsystem; AO Smith, responsible for design of the thermal storage and water heating subsystems; Trane, a business of American Standard Companies, responsible for design of the HVAC subsystem; and AirXchange, Inc., responsible for design of the mechanical ventilation and dehumidification subsystem.
Date: January 31, 2009
Creator: Gerstmann, Joseph
Partner: UNT Libraries Government Documents Department

Energy storage technology-environmental implications of large scale utilization

Description: Environmental impacts for several energy storage technologies have been identified. State-of-the-art control technology options were similarly identified. Recommendations for research and development on new control technology were made where present controls were either deemed inadequate or non-existent. Specifically, the energy storage technologies under study included: advanced lead-acid battery, compressed air, underground pumped hydroelectric, flywheel, superconducting magnet and various thermal systems (sensible, latent heat and reversible chemical reaction). In addition, a preliminary study was conducted on fuel cell technology. Although not strictly classified as an energy storage system, fuel cells in conjunction with product recycling units can serve an energy storage function. A very large number of potential environmental impacts can be identified for all of these technologies. However, not all are of primary importance. Detailed discussions of a number of environmental impacts from the latest LASL study as they relate to primarily operational situations are emphasized. In addition, a brief discussion on new application for energy storage technologies and the additional costs of controls to be used for mitigation of specific impacts are also presented.
Date: January 1, 1979
Creator: Krupka, M.C.; Moore, J.E.; Keller, W.E.; Baca, G.A.; Brasier, R.I. & Bennett, W.S.
Partner: UNT Libraries Government Documents Department

HYCSOS: a Chemical Heat Pump and Energy System Based on Metal Hydrides

Description: The HYCSOS chemical heat pump and energy conversion system based on metal hydrides are described. The HYCSOS thermal energy storage and recovery modes; the chemical heat pump heating and cooling modes as well as the energy conversion mode are discussed in detail with the aid of heat transfer fluid and hydrogen flow diagrams. The thermodynamic efficiencies of the two metal hydride system are calculated for the heat pump and conversion modes. Design and construction features of a demonstration test facility which utilizes four stainless steel tanks holding 10 lbs. each of either LaNi5 or CaNi5 are given. The operation, instrumentation and control of the system is detailed with the aid of photographs, drawings and a system layout diagram. Initial operation of the system has shown that 33 moles of hydrogen can be transferred from CaNi5 at approximately 100 degrees C to LaNi5 at approximately 40 degrees C and recovered from LaNi5 at approximately 8 degrees C to reform CaNi5H4 at 40 degrees C with cycle times approaching 2 minutes for 50 percent hydrogen transfer. The relevant data pertaining to these experiments are given in graphs and tables. The next phase of operations will be done on the fully insulated system to establish a firmer data base, obtain power balances and determine optimum operating parameters. In order to achieve these goals in a reasonable time frame, a data display and handling system is required. A materials development program is being carried out concurrently with HYCSOS operations. Significant progress is being made in the development of new, more cost effective alloy systems displaying superior properties for heat pump action.
Date: June 1977
Creator: Gruen, Dieter M.; Sheft, Irving; Lamich, George J. & Mendelsohn, Marshall
Partner: UNT Libraries Government Documents Department