Optimal performance of an irreversible solar-assisted heat pump

Abstract

The thermodynamic optimization of a mechanically driven solar heat pump is presented. A new expression to describe the optimal thermal performance under finite operating conditions considering the internal and external irreversibilities during actual operation is derived. The optimum ratio between the condenser and collector–evaporator conductances (UA) determines the coefficient of performance (COP) for the maximum heating load of the system. An experimental air-R22 heat pump was used to determine the traditional performance parameters (COP and second law efficiency) which are compared with those obtained using the expressions derived in this work. Results show that the new model very closely represents the performance of real systems.