Multi‐pronged degradation analysis of a photovoltaic power plant after 9.5 years of operation under hot desert climatic conditions

Abstract Long‐term reliability assessment of photovoltaic (PV) modules is key to ensuring the economic viability PV systems. This paper presents a multi‐pronged performance degradation analysis 62.1 kWp solar power plant after 9.5 years operation. For this purpose, various diagnosis techniques, namely, visual inspection, infrared thermography (IR), ultraviolet fluorescence (UVFL) and current‐voltage (I‐V) characterization, have been performed evaluate plant. The characterization results show that strings are affected by different mechanisms with degrees occurrences. observed level occurrence among were found be, encapsulant discolouration (100%), degraded frame adhesive (57%), junction box (39%), snail trails (30%), burn marks (3%), cell cracks (2%) delamination (0.4%). Although was most common possible mechanism observed, main causes loss in cells. Furthermore, IR UVFL provided better understanding on phenomenon crack modules. Besides imaging assess electrical system, we power‐voltage (P‐V) entire from which rates parameters determined. Our for maximum fill factor 0.84%/year 0.66%/year, respectively, over operating period installation. estimated rate installation could be considered as realistic installed harsh hot desert climatic conditions. Additionally, our work has raised doubts about validity warranties proposed manufacturers.