Conservative estimates indicate that the United States uses 4.7% of its energy consumption on air conditioning and refrigeration (3.3 x 10¹⁵ Btu/year). The size of this usage coupled with highly seasonal demand and primary utilization of a single energy source has caused severe immediate problems in energy allocation. It is readily apparent that even small percentage reductions in this energy usage can be major in terms of Btus: a decrease of 1% would mean saving 3.3 x 10¹³ Btu/year and, at a rate of 1 cent per 1,000 Btus, a saving of $330 million/year.

It is evident then that the incentive for increasing the efficiency of cooling systems is great. The purpose of this paper is to indicate desirable goals by comparing typical performance characteristics of currently manufactured cooling systems with the corresponding perform~nce of ideal systems.