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The principal objective of the project is to test and evaluate the practicality of an integrated evacuated tube solar collector and absorption space cooling system installed in Colorado State University (CSU) Solar House III. This objective was to be accomplished by designing and installing a complete solar heating and cooling system (including appropriate instrumentation), performing detailed analysis and evaluation of all aspects of the system, and comparing seasonal performance with two other solar heating and cooling systems installed in adjacent buildings with virtually identical thermal characteristics. The two comparison system, installed in CSU Solar Houses I and II, consist of conventional solar water-heating and air-heating flat-plate collectors. The system in CSU Solar House III was comprised of a 48 m/sup 2/ (512 ft/sup 2/) liquid-heating evacuated tube solar collector array, 4550 liter (1200 gallon) thermal storage water tank, 7.03 kW (2-ton) lithium bromide absorption chiller, cool storage subsystem, and other components of the heating and cooling system.

The state-of-the-art of solar collector corrosion processes is reviewed, and Task 1 of a current research program on use of aqueous heat transfer fluids for solar heating and cooling is summarized. The review of available published literature has indicated that lack of quantitative information exists relative to collector corrosion at the present time, particularly for the higher temperature applications of solar heating and cooling compared to domestic water heating. Solar collector systems are reviewed from the corrosion/service life viewpoint, with emphasis on various applications, collector design, heat transfer fluids, and freeze protection methods. Available information (mostly qualitative) on collector corrosion technology is reviewed to indicate potential corrosion problem areas and corrosion prevention practices. Sources of limited quantitative data that are reviewed are current solar applications, research programs on collector corrosion, and pertinent experience in related applications of automotive cooling and non-solar heating and cooling. A data bank was developed to catalog corrosion information. Appendix A of this report is a bibliography of the data bank, with abstracts reproduced from presently available literature accessions (about 220). This report is presented as a descriptive summary of information that is contained in the data bank.

As solar heating systems become a commercial reality, greater efforts are now being employed to incorporate solar cooling components in order to obtain a complete solar heating and cooling system, and thus take advantage of the cost-effectiveness of year-round use of the solar equipment. The solar heating and cooling system design presented incorporates design considerations which have been obtained from previous experimental efforts utilizing evacuated tube solar collectors. These advanced collectors are capable of significantly higher efficiencies, even at the higher temperatures required for solar cooling operation. Most of the considerations presented are based on the experience gained in the design and performance of the solar heating and cooling systems for CSU Solar Houses I through IV.

The bulk of the technical effort was devoted to the evaluation of a residential solar heating and cooling system utilizing an array of evacuated tube solar collectors. In May 1978, the evacuated tube collectors were removed and replaced with a state-of-the-art liquid-heating flat-plate solar collector array. First, the installation, performance, and operating experience of the Owens-Illinois (O-I) evacuated tube solar collector integrated with the CSU Solar House III residential sized solar heating and cooling system is dealt with. The second section discusses four months of installation, operation, and evaluation of the Chamberlain flat-plate collectors installed on CSU Solar House III.

The objective of this study was to test and evaluate the practicality of an integrated flat-plate state-of-the-art liquid-heating solar collector and absorption cooling system installed on Colorado State University (CSU) Solar House III. This objective was accomplished by designing and installing a complete solar heating and cooling system (including appropriate data acquisition equipment and instrumentation), performing a detailed analysis and evaluation of all aspects of the solar system, and comparing the seasonal performance of the system with two other solar heating and cooling systems installed in adjacent buildings with virtually identical thermal characteristics.

The Solar Heating and Cooling Demonstration Act of 1974 created a set of activities to demonstrate the potential use of solar heating within a three-year period and of combined solar heating and cooling within a five-year period. This study assesses the Commercial Demonstration Program portion of the activity in terms of its stated goals and objectives. The primary data base was DOE contractor reports on commercial demonstration projects. It was concluded that the program did not provide data to support a positive decision for the immediate construction or purchase of commercial solar systems. However, the program may have contributed to other goals in the subsequent legislation; i.e., research and development information, stimulation of the solar industry, and more informed policy decisions.

A broad range of difficulties encountered in active and passive solar space heating systems and active solar space cooling systems is covered. The problems include design errors, installation mistakes, inadequate durability of materials, unacceptable reliability of components, and wide variations in performance and operation of different solar systems. Feedback from designers and manufacturers involved in the solar market is summarized. The designers' experiences with and criticisms of solar components are presented, followed by the manufacturers' replies to the various problems encountered. Information is presented on the performance and operation of solar heating and cooling systems so as to enable future designs to maximize performance and eliminate costly errors. (LEW)

This report is a summary of an evaluation of the weather data set, generated at Sandia Laboratories, known as the Typical Meteorological Year (TMY) Data. The purpose of the evaluation is to determine how well the TMY data represent actual long-term weather data in affecting the performance of solar heating and cooling systems. The two data sets are compared through detailed SHAC simulation.

The Solar Heating and Cooling Commercialization Research Program has addressed a recognized need to accelerate the commercialization of solar products. The development of communication techniques and materials for a target group of heating, ventilating and air-conditioning (HVAC) wholesalers and distributors has been the primary effort. A summary of the program, the approach to the development of the techniques and materials, the conclusions derived from seminar feedback, the development of additional research activities and reports and the recommendations for follow-on activities are presented. The appendices offer detailed information on specific elements of the research effort.

The Solar Heating and Cooling (SHAC) in Residential Building Demonstration of 1974 is assessed. The program's goals and the Government Accounting Office's (GAO) evaluation of the program's success are stated. The program is analyzed with regard to objectives, results, data, and the GAO's conclusions. The differing approaches of the GAO and the Department of Housing and Urban Development (HUD) to the program are analyzed and compared, showing weaknesses in each. Conclusions on the relative success of the program are drawn, and recommendations are made regarding any future programs of this type. (LEW)

The results of a series of telephone interviews with groups of users of information on active solar heating and cooling (SHAC). An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from 19 SHAC groups respondents are analyzed in this report: DOE-Funded Researchers, Non-DOE-Funded Researchers, Representatives of Manufacturers (4 groups), Distributors, Installers, Architects, Builders, Planners, Engineers (2 groups), Representatives of Utilities, Educators, Cooperative Extension Service County Agents, Building Owners/Managers, and Homeowners (2 groups). The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

The final results of the additional development work on heat transport fluids for use with active solar heating and cooling systems are summarized. The intended use of the final report is discussed, the deliverable end items are described, program objectives are listed, and means of accomplishment and problems encountered during testing are covered. It is shown that a certain product tested is marketable and is recommended as being suitable for public use.

The solar heating and cooling system installed at the headquarters of Citizens Mutual Savings Association in Leavenworth, Kansas, is described in detail. The project is part of the U.S. Department of Energy's solar demonstration program and became operational in March, 1979. The designer was TEC, Inc. Consulting Engineers, Kansas City, Missouri and contractor was Norris Brothers, Inc., Lawrence, Kansas. The solar system is expected to furnish 90 percent of the overall heating load, 70 percent of the cooling load and 100 percent of the domestic hot water load. The building has two floors with a total of 12,000 square feet gross area. The system has 120 flat-plate liquid solar panels with a net area of 2200 square feet. Five, 3-ton Arkla solar assisted absorption units provide the cooling, in conjunction with a 3000 gallon chilled water storage tank. Two, 3000 gallon storage tanks are provided with one designated for summer use, whereas both tanks are utilized during winter.

The objective of the project entitled, Coordination/Management Tasks for the IEA Solar Heating and Cooling Program and CCMS Solar Energy Pilot Study, was to provide support to DOE in connection with the afore-named multilateral cooperative projects. The work included both management assistance for the overall IEA and CCMS projects and technical involvement in IEA Task I, particularly the solar system performance validation effort. The final report, covering the period March 15, 1979 - September 30, 1980, provides an overview of the accomplishments under this contract and gives conclusions and recommendations for future work. Also included in this document is the final project status report for the period May 15, 1980 to September 30, 1980.

This study concerns the acceptability of solar heating and cooling to homebuyers for residential applications. The study assesses the extent of homeowner awareness of solar technologies, estimates the acceptability of elevated first costs including willingness to trade higher initial costs for life cycle savings, and investigates the impact of solar aesthetics. Also explored are other areas of potential concern to homeowners in evaluating a solar alternative as well as positive motivations that would encourage purchase. Finally, the socioeconomic and attitudinal characteristics of individuals more likely to purchase a solar home rather than a conventional home were studied. The results are based on group depth interviews and personal interviews with active homeseekers, top executives of large residential development firms, and architects. The sample was split evenly between Denver, Colorado and the Philadelphia, Pa./Wilmington, Del. areas. Implications of the results for the commercialization of solar energy and possible public policy decisions are also discussed.

Telephone screener questionnaires and mail-out questionnaires for marketing surveys for solar heating and cooling equipment are presented. Questionnaires are included for the residential segment, industrial segment, HVAC professionals segment, builder/developer segment, and the commercial segment. No results are reported. (WHK)

On 1 February 1976, the Energy Research and Development Administration awarded the Solar Energy Applications Laboratory of Colorado State University a grant to design, install, and test a residential solar heating and cooling system using an evacuated tube solar collector. The progress of the project during the first six months (1 February 1976 through 31 July 1976), is reported.

The objective of the Vee-Trough/Evacuated Tube Collector (VTETC) Project, undertaken for the DOE Solar Heating and Cooling Branch, was to show how vee-trough concentrators could improve the heat collection capability and reduce the cost of collectors consisting of evacuated tube receivers. The work was carried out in two phases. During the first phase, the VTETC was analyzed rigorously and various mathematical models were developed to calculate the optical performance of the vee-trough concentrators and the thermal performance of the evacuated tube receivers. A test bed was constructed to verify the mathematical analyses and compare reflectors made of back-silvered glass mirror, Alzak, Aluminized Teflon, and Kinglux (an electro polished aluminum reflector). Testing was conducted and data was obtained for the months of April to August 1977. The results of the mathematical analyses, as well as the results from 1977, were reported in DOE/JPL/1024-1, published in January 1978. In the second phase, additional tests were run at temperatures ranging from 80 to 190/sup 0/C (176 to 374/sup 0/F) during the months of April, May, June, and July 1978. The results obtained compared well with theoretical predictions. For the glass mirror reflectors, peak efficiencies, based on aperture area and operating temperatures of 125/supmore » 0/C (257/sup 0/F), were over 40%. Efficiencies of about 40% were observed at temperatures of 150/sup 0/C (302/sup 0/F) and 30% at 175/sup 0/C (347/sup 0/F). Test data covering a complete day are presented for selected dates throughout the test season. Predicted daily useful heats collected and efficiency values are presented for a full year. These theoretical values are then compared with actual data points for the same temperature range.« less

Gylcols, polygloycols, silicone oils, hydrocarbon oils and various corrosion inhibitors and biocides used in solar heating and cooling systems are tested and evaluated for their potential effects on soils, vegetation, and in regard to potential groundwater contamination. Experimental tests include measurement of the effects of additions of these substances to soils on soil microbial respiration, above ground vegetation, and on the mobilization of chemicals in soil water, including the test substance and any significant biodegradation products. Experimental work aims at developing the data base necessary to evaluate the environmental acceptability of the wide range of materials used for this purpose, addressing the need for development of disposal practices and the means of mitigating effects on the environment due to accidental releases.

Separate abstracts were prepared for each of the six papers included. Volume I covers solar heating and cooling of buildings.

Unlike several other programs by which buildings and the performance of solar heating and cooling equipment can be analyzed, this program is capable of estimating the cost of backup electric energy from a utility's actual cost of supply, in addition to its rate structures. In its present form, the program permits the specification of a wide variety of solar or conventional heating and cooling devices which use electric energy. Both thermal loads of the residence and the utility's system-wide load are dependent upon a weather tape which is used in hourly computations extending over one year. Monthly costs of electric energy are based upon the hourly electrical demand of the residence and the utility's cost-of-supply model. When combined with equipment costs and specified economic parameters, these monthly energy costs are used to predict total life-cycle costs for each system considered, and to show payback periods when compared with conventional equipment.

A review of general techniques and specific methods useful in the optimization of solar heating and cooling systems is undertaken. A discussion of the state-of-the-art and the principal problems in both the simplified thermal performance analysis and economic analysis portions of the optimization problem are presented. Sample economic analyses are performed using several widely used economic criteria. The predicted thermal results of one typical, widely used simplified method is compared to detailed simulation results. A methodology for and the results of a sensitivity study of key economic parameters in the life cycle cost method are presented. Finally, a simple graphical optimization technique based on the life cycle cost method is proposed.

The type of materials research most likely to improve the durability and efficiency of future active and passive solar heating and cooling systems is analyzed. Research needs are compared with ongoing solar materials research, and the extent to which present research efforts are addressing the critical flat plate collector needs is assessed. Areas most in need of additional attention are identified. Research recommendations are made for glazing materials, selective absorbers, and heat transfer fluids. (LEW)

The first year of operation of solar house is discussed. Selected design information, together with a brief system description is included. The house was equipped with an integrated solar heating and cooling system which uses fully automated state-of-the art. Evaluation of the data indicate that the solar house heating and cooling system is capable of supplying nearly 100 percent of the thermal energy required for heating and approximately 50 percent of the thermal energy required to operate the absorption cycle air conditioner.

The installation of Solar Heating and Cooling of Building (SHACOB) systems usually requires a backup system--often electric--to take some portion of the load on days of low insolation, and to carry the entire load during extended periods of low insolation. The implications of such systems on the economic operation of electric utilities may be significant if a displacement of required generating capacity does not accompany the displacement of energy. The objective of this study was to assess the economic impact of various SHACOB design concepts on the electric utilities and their customers and to define system requirements for optimizing this impact. Weather and insolation inputs for simulations were established for locations across the United States. Reference buildings and their thermal properties were defined according to ASHRAE 90-75 standards, and detailed internal and external load models generated to characterize building thermal performance. The TRNSYS program was modified to simulate the performance of both solar and conventional systems, including load management systems featuring nighttime thermal storage. The systems analyzed in detail were direct solar systems with and without a load management capability, solar assisted heat pumps, and customer load management systems. These systems were evaluated with respect to conventional resistive and heatmore » pump systems. Projections for new buildings and types of heating system installations in those buildings were developed by eight participating utilities for their own service areas. TRNSYS simulations for the various types of systems in a wide variety of building types were used to generate backup electric demand time histories for representative cities in or adjacent to the eight service areas.« less

The use of solar energy for home heating and cooling is often considered to be environmentally benign and to present few or no health hazards. However, all technologies impact the environment, and all can introduce situations that lead to personal harm and property loss. Environmental impact and hazardous situations can be minimized if the needed information is identified and communicated to users and designers during the early development stages of a technology. The goal of this program is to provide a single reference source of hazardous properties and environmental effects of materials used in solar heating and cooling for heat transfer fluids, insulations, seals and sealant materials, glazing material, collector material, and storage material. Hazardous properties that are emphasized are those related to toxicity (using Durham and Gasselin rating schemes) and fires (using rating schemes for Health Hazard Identified for Firefighters, Flammability Hazard Identified for Firefighters, and Reactivity/Stability Hazard Identified for Firefighters). Chemical characterizations of some materials are presented and environmental effects are surveyed. This interim handbook is the first of several editions. Comments and suggestions for improvement are solicited from qualified spokespersons. New data and expanded treatments will follow in later editions. (AN)

A description is given of the solar energy system for the National Security and Resources Study Center, a conference center and library at the Los Alamos Scientific Laboratory, Los Alamos, New Mexico. The solar heating and cooling system makes use of selectively coated collectors, hot storage, cold storage, night evaporative cold storage, heat recovery, a lithium bromide chiller, and a Rankine-cycle chiller. Data are given for the performance of the system for the years 1978 and 1979. The solar energy system has provided 76% of the energy required to heat the building and 97% of the thermal energy required to cool the building.

The Solar Energy Applications Laboratory of Colorado State University has completed the design, construction, and installation of a complete set of evacuated tubular collectors on a test bed behind Solar House I. The collectors, the Corning evacuated tube collector (December 16, 1976 to December 31, 1977) and the Philips evacuated tube collector (January 16, 1978 to January 31, 1979) are being used sequentially to operate the heating and cooling system of Solar House I. Data are being collected over an entire heating and cooling season and analyses are being performed on these data to provide an evaluation of the two new collectors and comparison with the present conventional collector as part of a residential heating and cooling system that is otherwise identical in every way. This project is significant for several reasons. First, the two high performance collectors operate in conjunction with an advanced ARKLA lithium bromide water chiller. This cooling unit is designed specifically for operation with solar energy systems. For comparative purposes the advanced ARKLA unit will be available for use with the existing conventional flat-plate collector. In addition, comparisons of operating data are being made with Solar Houses II and III, adjacent to Solar House I. Solarmore » Houses II and III have the same thermal load characteristics as Solar House I, but have different solar heating and cooling systems. House II has an air heating collector and pebble-bed storage. House III has an evacuated tube solar collector, and is also coupled with an advanced absorption water chiller unit. The comparative analysis under the same load conditions, provides an exceptional opportunity in evaluating the relative merits of the new collector systems.« less

During the period 1 February 1976 through 31 March 1977, a residential solar heating and cooling system was designed, installed, and operated in CSU Solar House III. The system consists of 512 square feet of Owens-Illinois (O-I) Evacuated Tube Solar Collector, a 2.2-ton lithium bromide absorption cooling unit (Yazaki Corporation), thermal storage units, and associated equipment. During the installation and inital operation of the system, numerous aspects of the feasibility of this system design have been evaluated. Many of these aspects point to the potentially improved operating performance and long-term durability of a solar air-heating evacuated tube solar collector.

The retrofitted solar heating and cooling system installed at the Florida Solar Energy Center is described. Information is provided on the system's test, operation, controls, hardware and installation, including detailed drawings. The Center's office building, approximately 5000 square feet of space, with solar air conditioning and heating as a demonstration of the technical feasibility is located just north of Port Canaveral, Florida. The system was designed to supply approximately 70% of the annual cooling and 100% of the heating load. The project provides unique high-temperature, non-imaging, non-tracking, evacuated-tube collectors. The design of the system was kept simple and employs five hydronic loops. They are energy collection, chilled water production, space cooling, space heating and energy rejection.

TRNSYS-compatible subroutines for the simulation of chemical heat pumps have been written, and simulations (including heating, cooling, and domestic hot water) have been performed for Washington, DC and Ft. Worth, Texas. Direct weekly comparisons of the H/sub 2/SO/sub 4//H/sub 2/O and CaCl/sub 2//CH/sub 3/OH cycles have been carried out. Projected performance of the NH/sub 4/NO/sub 3//NH/sub 3/ cycle has also been investigated, and found to be essentially identical to H/sub 2/SO/sub 4//H/sub 2/O. In all cases simulated, the solar collector is a fixed evacuated tube system, which is necessary because chemical heat pumps operate at higher solar collector temperatures (> 100/sup 0/C) than conventional solar systems. With standard residential loads, the chemical heat pumps performed surprisingly well. In the Ft. Worth climate, less than 45 m/sup 2/ of collectors were required to meet over 90% of the heating and cooling loads. In Washington, DC, the area required to meet the cooling load was smaller (as little as 20 m/sup 2/, depending on window shading), but was sufficient to meet only 50 to 60% of the heating load. However, gas-fired backup via the heat pump was quite effective in reducing fossil fuel consumption: the thermal COPs in the heating mode weremore » in the range 1.6 to 1.7. Since chemical heat pumps are designed to reject heat at relatively high temperatures, they were also effective in providing domestic hot water, supplying ca. 70% of the DHW in summer, ca. 50% in winter, and nearly 100% in spring and fall.« less

One of the many factors which must be considered in performance evaluation of solar energy systems is the relative merit of a given solar energy system when compared to a standard conventional system. Although initial and operational costs will be dominant factors in the comparison of the two types of systems and will be given prime consideration in system selection, sufficient data are not yet available for a definitive treatment of these variables. It is possible, however, to formulate relationships between the nonsolar energy requirements of the solar energy systems and the energy requirements of a conventional system in terms of the primary performance parameters of the systems. Derivations of such relationships, some parametric data for selected ranges of the performance parameters, and data with respect to limiting conditions are presented.

A methodology has been defined to arrive at control recommendations for a variety of climate control system designs, applications and regions, and the results are presented in two parts. Part I consists of a literature and market-place survey, involving control strategies, functions, sensors, actuators, and the controllers themselves. Part II represents the bulk of the study effort - an attempt to simulate and evaluate system performance for several representative residential and commercial heating and cooling designs and thus to derive improved performance techniques within cost-effective control systems. (MHR)

During the period 1 October 1978 through 31 March 1979, the Chamberlain liquid-heating state-of-the-art flat-plate solar collector was evaluated for a complete heating season. The data acquisition and analysis was a continuation of the cooling season performance evaluation conducted during the summer and fall of 1978. Significant and important results of the systems evaluation include: (1) The demonstration of the critical importance of temperature differentials between the collector outlet and the absorption chiller generator inlet, the effects of alternative control strategies, the marginal feasibility of cool storage, the devastating effect on system performance due to heat losses from the thermal storage unit, and the importance of minimizing electrical parasitic power requirements in obtaining feasibility for solar absorption cooling systems. (2) The concept of overall system efficiency was shown to be essential in the determination of the feasibility of any solar installation. (3) Evaluation of acquired data on the performance of the CSU Solar House III system has provided the theoretical construction and experimental verification of the importance of solar operating threshold (i.e., the minimum solar radiation intensity at which the collector can collect useful solar heat).