Storage of low-temperature heat in salt-hydrate melts: Calcium chloride hexahydrate

Abstract

Calcium chloride hexahydrate melts at 29.8/sup 0/C. Its heat of fusion is 170 J/g or 71.7 kWh/m/sup 3/ of solution. In the temperature interval 20 to 30/sup 0/C, it has a heat content comparable to a temperature increase from 20 to 90/sup 0/C in the equal volume of water. Its high heat-storage capacity just above room temperature is especially advantageous for use in solar heating. The report discusses, in general, the choice of heat storage medium; the particular merits of calcium chloride and method for adapting this substance for this use. Experiments to describe heat transfer characteristics of a heat of fusion storage system and the construction of such a system are reported.