Theoretical and experimental study on the uniformity of reflective high concentration photovoltaic system with light funnel

Abstract The efficiency of GaAs solar cell was significantly reduced resulting from non-uniformity of energy flux-density on receiver surface, and damage of solar cells was made by “hot spots”. In this paper, a light funnel is added between the concentrator and the receiver to improve the uniformity of energy flux-density on receiver surface, which is designed according to the ray tracing method. The simulation result shows that the uniformity of the energy flux-density on the receiver surface is 92.26%, which agrees with the experimental result (94.64%). According to the maximum output efficiency of GaAs solar cell, the layout range of the cell is determined. The simulation results shown that the cell is arranged in the radius of 58 mm, which is similar to the experimental value (60 mm), and the effective area rate of the photoelectric conversion is 69.4%. At normal operation temperature (20 °C), the photoelectric conversion efficiency is 29.64%, and the total efficiency is about 83%.