Realization and Use of an IR Camera for Laboratory and On-field Electroluminescence Inspections of Silicon Photovoltaic Modules

Electroluminescence (EL) is a non-destructive technique, which detects the most common defects in Photovoltaic (PV) modules. High resolution EL images are generally obtained by infrared-sensitive cameras equipped with different semiconductors (indium gallium arsenide or silicon sensors). In the present work, a procedure is proposed to build and set up a high resolution EL camera for crystalline Si modules, equipped with a low-cost Si sensor. It can be used to perform EL test both indoor (lab) and outdoor (on-field). Experimental results from real PV plant highlight the combined use of I-V curves and EL images, for determining the amount of power losses and their causes.