Potential-induced degradation (PID) is still one of the main reasons for unpredictable power losses in PV power plants. Volker Naumann, Otwin Breitenstein, Klemens Ilse, Matthias Pander, Kai Sporleder and Christian Hagendorf of Fraunhofer CSP examine how the PID susceptibility of PV modules is influenced by environmental stress. It is found that PID may develop in originally PID-resistant modules after a period of one to three years of unsuspicious operation, depending on climatic conditions
