An experimental comparison between view factor and ray tracing models for energy estimation of bifacial modules

Albedo, or the ground reflectance irradiance, is one of the crucial variables in the energy estimation for bifacial photovoltaic modules due to the modules' ability to collect electricity from both front and rear sides. There are several modeling tools for the energy estimation of these modules. Our paper reports on the comparison of on two available energy estimation models with view factor and ray tracing and compares the estimated data with actual measured values. For a one-year data gathered at the Anhalt Photovoltaic Performance and Lifetime Laboratory (APOLLO) in Bernburg, Germany, the view factor model-based algorithm for a bifacial module is more accurate when predicting PV energy yield. Furthermore, an albedo sensitivity analysis concludes that the tested Ray-tracing algorithm overestimates bifacial PV energy for large albedo values. However, the tested modeling methods follow the measured data trend with a deviation between −8 % to 6 %.