Outdoor performance analysis of a 1090x point-focus Fresnel high concentrator photovoltaic/thermal system with triple-junction solar cells

摘要

A high concentrator photovoltaic/thermal (HCPV/T) system based on point-focus Fresnel lens has been set up in this work. The concentrator has a geometric concentration ratio of 1090x and uniform irradiation distribution can be obtained on solar cells. The system produces both electricity and heat. Performance of the system has been investigated based on the outdoor measurement in a clear day. The HCPV/T system presents an instantaneous electrical efficiency of 28% and a highest instantaneous thermal efficiency of 54%, which means the overall efficiency of the system can be more than 80%. A mathematical model for calculating cell temperature is proposed to solve difficult measurement of cell temperature in a system. Moreover, characteristics of electrical performance under various direct irradiation intensity and cell temperature are also studied. The results show that direct irradiation affects the electrical performance of the system dominantly. Fitting results of electrical performance offer simple and reliable methods to analyze the system performance. (C) 2015 Elsevier Ltd. All rights reserved.