Irradiance modelling for bi-facial PV modules using the ray tracing technique

Bi-facial PV modelling software is scarce and existing software mainly implements the view factor model which may neglect a number of effects that greatly influence the rear side irradiance of bi-facial modules. This paper shows the results of bi-facial PV simulation software that is being developed by implementing the ray tracing technique to model the factors that lead to increased energy yields of bi-facial PV technology. A bi-facial PV plant is modelled by interfacing Radiance (ray tracing software) with python based simulation software. Simulation results are compared with real world irradiance measurements to determine the accuracy of the developed software model. The preliminary results of the simulation software are promising and show that ray tracing techniques can satisfy the shortcomings of existing bi-facial PV simulation software with more accurate modelling of the rear side irradiance of modules.