Understanding and Benchmarking Ground Reflectors for Bifacial Photovoltaic Yield Enhancement

Bifacial modules combined with optimally positioned ground reflectors (albedo) can boost photovoltaic (PV) yield. Yet, a rigorous understanding and benchmarking of the reflector performance is missing, which leads to errors in power yield and economic estimates, thus hampering PV market penetration. Here, we address this impediment by establishing an experimentally validated reverse ray tracing (RRT) approach, combined with empirically derived parameters. First, we determine the spectro-angular reflection of a wide class of ground reflectors (diffuse, glossy, and specular). These parameters were fed into our RRT software, that simulated the PV yield, which was then experimentally validated with a model PV system. The validated framework enables determining an upper limit to PV yield enhancement and current mismatch within modules exposed to different kinds of reflectors. Our approach helps assessing already-existing natural and exotic reflectors, and inspire novel reflectors for enhanced PV yield and economic benefits.