Optimal collector temperature for solar-driven heat pumps

The optimal performance of an endoreversible solar-driven heat pump system consisting of a solar collector and a three-heat-reservoir heat pump is investigated. Two heat transfer models between the working fluid and the reservoirs of the heat pump are used in the system analysis. The overall coefficient of performance (COP) and heating load of the system are adopted to be the objective functions of the analysis. The analytical results found in the paper provide a basis for designing a real solar-driven heat pump system.