Thermodynamic analysis of metal hydride-vapour compression hybrid systems

A thermodynamic analysis of hybrid systems incorporating metal hybride heat transformers (MHHT) and vapour compression heat pumps (VCHP) is presented. Two hybridisation concepts are analysed. In HYBRID1, the heat absorbed at the evaporator of VCHP is matched with the heat rejected at low temperature in the MHHT. In HYBRID2, the condenser heat rejection of VCHP is matched with the heat supply to MHHT at the intermediate temperature level. Eight different metal hybride pairs are considered for operation of MHHT. R12 and R11 are considered as vapour compression system working fluids for low temperature and high temperature applications respectively. Performance of hybrid systems is compared with that of single stage or cascaded VCHP systems. It is observed that the HYBRID2 concept is more advantageous over a wide range of temperature levels, in particular at high heat delivery temperatures. © 1987.