This paper will present a brine-based ice storage system installed at a company located in Freeport, Illinois. This system, started in April of 1984, serves office areas and a small portion of the manufacturing area. Areas now served by the ice storage systems were formerly cooled by a centrifugal chiller.Tests of the operating characteristics of this system were conducted between 5:00 p.m., July 23, 1984, and 11:00 a.m., July 24, 1984. The test results are tabulated within this paper and appear as Table 1. Brine Cp and Sg for this project are listed in Table 2. These data are used to develop operating characteristics for a 24-hour period that reflects rising brine temperatures leaving the ice storage cells (hereinafter referred to as “field”). The distribution of temperatures leaving the field during nighttime hours will be discussed, as will effects of partial ice production before a daily discharge period. The method used by the author to calculate brine volume increase due to winter freezing will also be discussed.