Improving the temperature uniformity and power generation of a concentrated photovoltaic cell under highest solar concentration ratios

Concentrated photovoltaic systems (CPVs) concentrate sunlight on solar cells to generate electricity. Increasing the concentration ratio can keep the system at high power output when the ambient radiation is insufficient. For solar cells with an effective area of 1 cm², the concentration ratio of outdoor experiments usually does not exceed 1,000× . In this study, a novel ultra-high concentrated photovoltaic system (UHCPV) capable of withstanding a solar concentration ratio as high as 2,500× was developed. A light guide was incorporated to improve the uniformity of the light spot. A microchannel liquid cooling radiator and a centrifugal fan were used to cool the upper and lower surfaces of the cell, respectively. The effectiveness of the light guide and cooling module was demonstrated through numerical simulation and outdoor experimental research. The results indicate that at a concentration ratio of 900×, the maximum temperature of the cell surface decreased from 84.3 °C to 63.0 °C compared with that of a single microchannel liquid cooling radiator. At an ultrahigh concentration ratio of 2,500×, the maximum surface temperature reached 88.2 °C. Additionally, outdoor experiments were conducted to measure the electrical performance at concentration ratios ranging from 900× to 2,500× . When the concentration ratio was 1,600×, the maximum electrical power of the system was 23.21 W.