Mathematical and experimental investigation about the dual-source heat pump integrating low concentrated photovoltaic and finned-tube exchanger

Abstract

Traditional dual-source heat pumps are generally composed of separated flat PV evaporators and finned-tube evaporators connected in series or parallel, occupying too much extra space with low space/energy utilization. The heat pump system consisting of fins and low concentrated photovoltaic designed in this paper could obviously improve PV output and it brilliantly fixes the finned-tube structure under the concentrator. The compact structure could better exploit the three-dimensional space and energy, bring improvement of the comprehensive output and system performance. The experimental rig is built in Hefei, China with improved pipeline. The system shows a brilliant cooling effect on concentrated photovoltaics, lowering the temperature by about 50 °C, lifting the electrical efficiency by 4.6%. Interestingly, in the real outdoor environment, the efficiency of concentrated photovoltaics declines with the deteriorated irradiance (cloud cover), contrary to the traditional flat PV. On a sunny day, the average electrical efficiency, heating rate, power consumption, COPth, and COPPVT could be 14.4%, 2168 W, 592 W, 3.76, and 4.43 respectively. The impact of the mass injection and concentration ratio is also investigated mathematically. This article makes up the lacked experimental content, providing strong and reliable data support/reference for the actual design and performance prediction of the high-efficiency and low-carbon three-dimensional heat pump system.