The performance of a university's chilled-water thermal storage system was monitored for six consecutive months, March through August 1990. Gives a brief history of the system, which consists of two 1.5-million-gallon thermally stratified tanks installed below ground level. System performance metrics, such as the figure of merit and kW/ton ratio, are presented on both an instantaneous basis and average basis for the cooling season. Other system performance indicators, such as thermocline profiles in the tank, compressor power consumption, campus load, and ambient temperature, are also presented. The daily operational cycle was modified throughout the cooling season as the team gained experience with the system. Discussion include operational issues associated with the system, including those that may be peculiar to this installation.

KEYWORDS: chilled water supply, energy storage, performance, monitoring, history, temperature stratification, tanks, cooling season, compressors, energy consumption, ambient temperature, operations