Experimental Investigation of Potential Induced Degradation (PID) Impact and Recovery on Crystalline Photovoltaic Systems

The present study focuses on the effects of PID on the performance of c-Si based solar PV panels installed on the mid-southwestern-Morocco for 3 years. The investigation has been divided into two parts: (i) The measurement of the power drop due to PID; (ii) since the PID is a reversible phenomenon, the polarity inversion technique has been used to evaluate the PID recovery. Electroluminescence (EL) images and electrical characteristics of investigated PV modules as the most accurate way of power loss analyzing have been conducted as a verification routine. Results show that the rate of power output drop due to PID is between 1 and 4%/years. Furthermore, the polarity inversion for one day can make this defect no more visibly detected (using EL inspection) and show an improvement in the module's power output of 7.6%.