Performance testing of a heat-pipe PV/T heat pump system under different working modes

A heat-pipe solar (HPS) photovoltaic/thermal (PV/T) heat pump system, combining HPS PV/T collector with heat pump, is proposed in this paper. The HPS PV/T collector integrates heat pipes with PV panel, which can simultaneously generate electricity and thermal energy. The extracted heat from HPS PV/T collector can be fully used by heat pump, then the photoelectric conversion efficiency is substantially improved because of the low temperature of PV cells. The performance of the system is tested and the electrical performance between PV/T system and traditional PV panel is compared under the heating mode and heat collection mode. The results are as follows: The daily electrical efficiency, daily thermal efficiency, COPth and COPpv/t can reach 12.2%, 33.9%, 2.78 and 3.40 in heating mode. While in heat collection mode, these performance parameters can reach 12.9%, 25.3%, 1.96 and 2.52. The electrical efficiency of PV/T system is improved by 25.7% and 14.2% compared with traditional PV panel under the heating mode and heat collection mode, respectively.