Effect of shading on CIGS thin film photovoltaic modules

Power output of PV systems reduces when they are fully or partially shaded. Full shading can occur as a result of reduction in irradiance due to cloud cover while partial shading occurs due to nearby objects. The temporary loss of power due to full or partial shading of PV systems has been well investigated in the published literature. However, shading can induce failures in PV modules and cause permanent power loss or compromise the safety. This paper discusses shading-induced reliability issues in copper-indium-gallium-selenide thin film PV modules deployed at the Florida Solar Energy Center for over 12 years.