Numerical study on the performance of a solar-assisted heat pump coupled with a photovoltaic-thermal air heater

Solar-assisted heat pumps (SAHPs) with photovoltaic-thermal technologies are promising systems for efficiently converting solar energy into useful thermal energy. In this paper, the performance of a SAHP coupled with a novel photovoltaic-thermal air heater (PVTAH) was evaluated under various operating and geometrical parameters. The PVTAH used in this study has a triangular block to improve its thermal efficiency, which also increases the heat pump performance. Using the heat balance equations, a mathematical model was developed and validated through experimental results. With the developed model, the effects of the air mass flow rate, PVTAH area, solar intensity, ambient temperature, and inlet water temperature on the performance of the SAHP with a PVTAH were examined and discussed. The results indicate that the SAHP with PVTAH could operate independently without power from the grid under most conditions, as the PVTAH generates more power than the system requires. In addition, compared to the traditional air-source heat pump, the SAHP with PVTAH enhanced the coefficient of performance of the heat pump by 13.28 %. Consequently, the feasibility of the proposed system was confirmed and this hybrid system is worthwhile to promote and apply.