Thermal storage systems have been in existence for many years. Although many early applications involved systems installed in dairies, churches, and theaters, most current applications are used for continuous comfort cooling. The purpose of a thermal storage system is to create thermal energy and store it for use at another time.

There are several types of thermal storage systems in use today. These systems can be either the full or partial storage type.

In the typical full thermal storage system, the refrigeration system (chillers) generates ice at night when electrical utility rates are typically lowest (off-peak). During the day, when utility rates are higher (on-peak), the ice is then melted to provide cooling to the building.

In the partial thermal storage system, a reduced size chiller or refrigeration system operates in conjunction with the ice storage to meet the peak loads.

There are several types of partial storage systems whose application is dependent on building loads, system equipment and energy costs. However, many partial storage systems are used to “shave off” peak energy demands to reduce operating costs.

The product technology that EVAPCO provides for the thermal storage industry is referred to as “ice on coils”.

In this type of system, cylinders of ice are built onto the tubes of hot dipped galvanized steel coils.

In most systems that use this technology, multiple banks of coils are submerged under water in field constructed concrete tanks.

Ice storage tanks are up to 8 times smaller than chilled water tanks for the same thermal capacity, saving space and cost.