Extracting Cell Level Characteristics from Photovoltaic Module Electroluminescence Images

Electroluminescence (EL) images are obtained to examine photovoltaic (PV) modules. EL images are typically utilized for qualitative analysis. This work presents a quantitative analysis technique for extracting cell level characteristics from calibrated module level EL images. Cell dark current-voltage (IV) data are extracted from EL images at various injection levels. Challenges are discussed along with actual and potential solutions to further improve the method’s accuracy and precision. It has been shown that the EL sweep results are in relative agreement with cell measurements; however, improvements are in progress.