Discoloration of photovoltaic module and correlation with electrical parameters degradation

Abstract

In this paper, the effect of module discoloration on electrical parameters degradation was analyzed. The discoloration was initially identified through visual inspection method. The visual image shows that the module has changed color to brown, and there is no discoloration on the module metallization. Furthermore, the module discoloration was correlated with the electrical parameters degradation. The analysis shows that Isc and Pmax have degraded high. This indicates that discoloration defect has correlated well with Isc and Pmax degradation. The annual power degradation rate of module 1 and 2 are found to be 2.25/year and 1.56/year respectively.