Research and development needs for chillers for energy conservation in air-conditioned buildings

Chillers have long been used in many air-conditioned buildings in the sub-tropical regions, but with considerable electricity consumption. This study explains some research areas required to improve their energy performance. A survey on over 300 current chiller models indicated the need to provide more useful data on the coefficient of performance (COP) of chillers at part load operation. An alternative performance rating method is proposed to specify precisely the COP of the chillers under various load and ambient conditions. An extensive search on state-of-the-art technologies highlighted the importance of controlling the chillers at optimum condensing temperatures in response to various combinations of chiller loads and outdoor temperatures. Further research and development areas for facilitating the improved control have been discussed.