Gail S. Brager, Department of Architecture

University of California Energy Institute

This project is examining the effectiveness of evaporative cooling systems for non-residential buildings in California, and providing information to improve the future implementation of such systems. Although the energy efficiency of evaporative cooling compared to compressor-based cooling is well documented in theory, there is very little actual field performance data on either energy or environmental performance that could be used to support the choice of such systems. Such information is essential, given that evaporative cooling technology has a negative image in California due to concerns about water and moisture damage, maintenance problems, and adverse health effects.

Field studies to gather operational evidence that evaporative cooling systems in some California regions can save energy and provide acceptable indoor environments have been completed. The field studies involved measurements of energy performance, indoor environmental quality, and occupant comfort and satisfaction in two large building in Santa Rosa and Lodi that contain evaporative cooling systems. The buildings under consideration have interesting operating histories with mixed success.

In the coming year, the data will be analyzed to describe the energy-saving potential and acceptability of indoor environments produced by such systems in comparison to conventional building system design. In addition, the history of evaporative cooling design, operation, and maintenance procedures will be reviewed to identify common problems. Recommendations to avoid such problems and achieve successful performance will be summarized in guideline form for the design, operation, and maintenance of evaporative cooling systems.