Influence of incidence angle effects on the performance of bifacial photovoltaic modules considering rear-side reflection

Improving the accuracy of performance evaluation of bifacial photovoltaic (PV) devices is critical to the development of bifacial PV technology. The incidence angle effect (IAE) is one of the characteristics related to the power generation of PV modules. Due to the ability of bifacial PV modules to collect light from double sides, the IAE evaluation should involve the effects of both the front and rear sides of PV simultaneously. This work aims to investigate the IAE of bifacial PV modules considering both front-side beam irradiation and rear-side reflection. The rear-side reflection makes the IAE of bifacial PV modules more complicated than that of monofacial PV modules. The rear-side IAE of bifacial PV modules was defined, and a corresponding mathematical model was derived theoretically in this work. A simulation model based on the view-factor method was developed to investigate the performance of bifacial PV modules under various incidence angles, whose validity was verified by indoor measurements. Furthermore, the results show that rear-side IAE is more suitable to be investigated with the simulation, and it is sensitive to the surrounding and installation conditions. The proposed method is applicable in evaluating and predicting the performance of bifacial PV modules related to IAE under different installation conditions.