Ice storage systems have the potential to save building owners a substantial portion of their air conditioning costs. In addition, electric utilities see this technology as one method to reduce summer peak demands on their systems. Most utilities offer rate incentives to encourage customers to consider this alternative.When one commercial customer decided to install an ice storage system in its new office, the local utility installed additional metering to monitor its performance. Several other ice storage installations are also being monitored.This report represents the results of the data analysis for the first two cooling seasons. It compares the system performance to a standard centrifugal chiller and also points out opportunities for maximizing the savings with the existing system.