| abstract |
A combination thermal energy storage material capable of functioning in two discrete temperature ranges and comprised of two constituents, one of which has a phase change in the low temperature range between about 35 DEG F. and about 55 DEG F., and the other of which has a phase change in the high temperature range of between about 90 DEG F. and about 130 DEG F. Both temperature ranges are selected to correspond with the operable and desirable ranges for a heat pump operation. The two constituents are selected to be non-reactive with one another and in the mixture maintain independent phase change characteristics. However, the mixture itself alters in some cases, depending upon concentration, the melting points of each member of the pair so that the transition temperatures of the phase changes in the mixture are somewhat different and somewhat lower than the phase changes characteristic of the independent constituents and is dependent upon the concentration of the constituents in the mixture. The pairs of materials selected can, therefore, function in the heat pump environment to provide a heat sink into which heat may be dissipated for air-cooling purposes as well as a heat source which provides heat for heating purposes. Preferred pairs of materials include (a) a hydrocarbon oil paired with a wax fraction; (b) a C8 fatty acid paired with a C14-C18 fatty acid; (c) a C10-C12 alcohol with a C14-C18 fatty acid; and (d) a C10-C12 alcohol with a wax fraction. Preferred weight percent of the components are also selected to conform to the high and low transition temperature ranges used as parameters. |