Thermal Energy Storage (TES) is an attractive strategy for efficient chilled water production when the difference between on-peak and off-peak power pricing is great. Further, the cost of cooling generated with electric chillers using electrical off-peak power is essentially half the cost of producing the same chilled water during the on-peak period. As such, the operational savings potential of thermal energy storage is substantial.

The most cost-effective TES technology for large-scale campus cooling systems is stratified liquid storage. This variety of TES can be seamlessly integrated into an existing chilled water system. The chillers will still operate as they always have and, if the system temperature differential is maintained, at the same efficiency.

KSC has begun pursuing partial load shedding TES operations. Here, the tank is optimized to avoid at least some cooling during a specified time period, but not all of it. This option is generally selected to optimize energy savings relative to first-cost of the TES installation. The partial load shed option requires a smaller tank than a full load shed option yet still reduces the amount of chiller capacity required and the monthly electric demand value.