Performance analysis of field-exposed multicrystalline silicon photovoltaic modules over 30 years

Abstract

In this paper, we present the energy performance and degradation of multicrystalline silicon photovoltaic (PV) modules after a 30-year operation under hot and humid climatic conditions. A comprehensive analysis was conducted by visual inspection, electrical performance evaluation, and system final yield evaluation. Visual inspection revealed the yellowing and delamination of ethylene vinyl acetate (EVA), and cracks in the backsheet were found to be the most frequent defects. It is possible to perform a comparison between final and initial parameters. The average performance degradation over 30 years from 1986 to 2016 is 6.51%. The annual average degradation has been found to be only 0.22%/year. System output power and performance ratio (PR) were also analyzed, giving an annual PR of 69.72%. These results indicate that the actual lifetime of PV modules is significantly longer than the warranty periods of 25 years, and still with good performance and reliability.