Annual performance evaluation and experimental study on variable speed compressors for room air conditioners.

Energy efficiency for room air conditioners has received increasing attention in recent years with the intense emphasis on environmental concern and energy consumption. As the main energy consumption component of air conditioner, compressor awaits further work to accomplish the transition of performance evaluation from one operation condition to its actual usage. In the present study, an evaluation index called annual efficiency is proposed to rate the annual performance of air conditioner compressor. Experimental study is conducted on four variable-speed compressors, and the results show that the best fit determined from annual efficiency is different from that of ASHRAE standard. The compressor efficiency and dynamic pressure are quite different at rated and half-capacity test conditions. Compressor running under half-capacity conditions is more energy efficient and peak phenomenon of dynamic pressure is less obvious when compared with rated conditions. Moreover, more attention should be paid to half-capacity conditions to improve the annual efficiency of compressor and energy-saving capabilities of air conditioners. [ABSTRACT FROM AUTHOR]