Power Generation Characteristics of Hybrid CPV/PV Module Measured in Long-term Field Test

Hybrid CPV/PV modules can achieve higher conversion efficiency than conventional concentrator photovoltaic (CPV) modules by utilizing the diffuse solar irradiance component. We fabricated a hybrid CPV/PV module consisting of a crystalline silicon (c-Si) solar cell stacked with LCPV with a geometric concentration factor of 16x and analyzed its power generation characteristics based on a 4-year long-term field test. The results showed that our hybrid CPV/PV module achieved a conversion efficiency of 17-35%, surpassing that of tracking-type flat-plate c-Si solar cells. The reason for this is that the Si cell can assist under conditions with a small fraction of direct solar irradiation. Under clear sky conditions, the CPV component provided about 80% of the power generated by the hybrid CPV/PV module. Although the conversion efficiency decreased as diffuse solar irradiance became dominant, the rate of decrease was smaller than that of the conventional CPV modules. The field tests were conducted under a variety of weather conditions except rainy weather, and the results obtained suggest the possibility of deploying hybrid CPV/PV modules.