Performance of a Passively Cooled Fresnel Lens Concentrating Photovoltaic Module

A passively cooled Fresnel lens concentrating photovoltaic module (FLCPM) was made and its performance was tested and analyzed. The module consists of a 0.480 m×0.480 m Fresnel lens array of 16 Fresnel lens with the size of each being 0.120 m×0.120 m, and the sunlight was concentrated onto 16 silicon solar cells with the size of each being 0.025 m×0.025 m that were placed at the focuses of the lenses. The solar cells were connected in series and passively cooled by being pasted onto an aluminum plate heat sink with thermally conductive electrically insulating adhesive. It was revealed by the outdoor test results that, the temperature of the solar cells could be restricted bellow 75.7 °C by the passive-cooling design under normal solar radiation conditions. Compared with non-concentrating photovoltaic module, the efficiency and fill factor of the FLCPM was lower. The optical efficiency loss, efficiency loss due to temperature increase in the solar cells and efficiency loss due to the un-uniform distribution of the concentrated sunlight were the main influence factors. Moreover, the maximum output power per unit area solar cell of the FLCPM was more than 7 times of that of the flat plate photovoltaic module.