UV Fluorescence for Defect Detection in Residential Solar Panel Systems

UV Fluorescence (UVF) is a relatively new "non-contact" method of detecting cracked cells in solar panels with potential high throughput and low cost. We report here on application of a pole-mount UV-flash camera system to the detection of defects on residential rooftops in Boulder Colorado. The majority of tested system exhibited useful UVF images, with most showing cracked cells, and a smaller percentage showing hot spot cells. Junction box heating and sealing problems and possible finger corrosion or encapsulant delamination were also seen. This data suggests that pole-mount UVF system is highly applicable and informative over a wide range of residential panel designs and ages and provides information complementary to that achieved from Electroluminescence imaging.