Power loss and hotspot analysis for photovoltaic modules affected by potential induced degradation

Potential-induced degradation (PID) of photovoltaic (PV) modules is one of the most severe types of degradation in modern modules, where power losses depend on the strength of the electric field, the temperature and relative humidity, and the PV module materials. Previous studies have only considered single effects of PID; however, this work investigates the power losses, development of hotspots, mm-level defects, and the performance ratio (PR) of 28 PID affected PV modules. Following a standard PID experiment, it was found that (i) the average power loss is 25%, (ii) hotspots were developed in the modules with an increase in the surface temperature from 25 to 45 degrees C, (iii) 60% of the examined PV modules failed the reliability test following IEC61215 standard, and (iv) the mean PR ratio is equivalent to 71.16%.