Analysis of Photovoltaic Performance Loss Rates of Six Module Types in Five Geographical Locations

In this paper, the annual performance loss rates (PLRs) of five different grid-connected photovoltaic (PV) technologies based on outdoor field measurements were computed. The data used were collected in five different geographical locations covering five climatic zones. The PLR values were determined as absolute and relative measures for all sites and module types using seasonal time series decomposition using local regression. The results are very consistent and show a clustering of the PLR for each technology, provided some explainable outliers are removed. This allows the conclusion that in presence of properly sized and quality-driven systems, the influence of different climates on the degradation of PV modules is not very strong. In the first approximation, individual degradations rate values computed in a single climatic zone can be seen as representative for the technology in general. The reason for this is that for defects there is an associated activation energy, which has not been reached yet in the systems analyzed in this study.