Recent investigations have determined that there are a number of advanced absorption cycles that can produce major gains in the energy efficiencies of absorption refrigeration, air conditioning, and heat pumping equipment. The advances are sufficient to reduce the annual operating costs of absorption heat pumps to well below those of other heating and cooling systems and to potentially reduce the national energy usage significantly. Major gains can be achieved with ammonia/water, the working pair presently best suited to heat pumps with high heatinput temperatures. However, the performance of some of the cycles can be increased further by the use of higher temperature fluids. The ternary combination of ammonia/lithium bromide-water recently has been shown to be usable to much higher temperatures than ammonia/water but to be much more corrosive. This project is to investigate materials that perform as well or better than lithium bromide in the ternary systems but have fewer disadvantages. Preliminary screening tests are planned to determine the suitability of the most promising ternary combinations. The properties to be measured include the vapor pressures of ammonia in the solutions, the crystallization limits, high-temperature stability, corrosion, and other characteristics that could affect the absorption cycle. If valuable ternary systems are found, the best one or two will be selected for more accurate study of the physical, thermodynamic, and transport properties in a possible Phase 11 program.Anticipated Results/Potential Commercial Applications as described by the awardee:If Phases I and II are completed successfully, one or more new working fluids would become available for absorption systems. They would, in turn, make possible, in Phase III or beyond, absorption systems for refrigeration, air conditioning, and heat pumping having higher efficiencies than are possible with the working fluids now available. The energy usages of such products should be much lower than those of other heating and cooling products. Heat pumps that can provide all the heat required by homes at outdoor temperatures of -20'F would also be possible. The high efficiencies could be applied to commercial and industrial uses as well. Heat sources for absorption systems include gas, oil, high- temperature solar, engine exhaust gases, etc.
