This project encompasses the development of a simulation tool for leakage currents in c-Si photovoltaic modules using the finite-element method. It accounts for variable material and surface properties due to changes in temperature, relative humidity, and surface wetting. Moisture diffusion from the module perimeter into the encapsulant and its resultant impact on charge transport is calculated. The electric field in the SiNx antireflection coating, which may affect shunting due to potential induced degradation, is also quantified; it can be greater than 10 kV/cm depending on temperature, relative humidity, and the SiNx properties. By simulating time-varying weather conditions, leakage currents in fielded modules can be predicted.
