Preventing Potential-Induced Degradation in Crystalline Silicon PV Modules: Relationship Between Degradation and Bill of Material

In this contribution we investigate the relationship between potential-induced degradation (PID) and the Bill of Material (BOM) used by module manufacturers. The BOM include two types of solar cells (conventional vs PID-free c-Si cells), two types of EVA films with, respectively, low and high resistivity, and two types of backsheets with, respectively, low and high permeability properties. Our results clearly indicate that to have a “PID-free” module the combination of PID-free cells and a high-resistive EVA encapsulants is recommendable. The use of a conventional c-Si cell in combination with a high-resistive EVA encapsulant, is still more effective than the use of PID-free cells in combination with low-quality EVA. These results, however, largely depend on the stress conditions applied during the PID test. Further, our results show that the permeability properties of the backsheet have apparently no influence on PID degradation.