Impact of High Temperature, Irradiance, and UV on Long-Term Performance of Solar PV Modules

This study examines the long-term degradation of a crystalline silicon photovoltaic (PV) module after 13 years of exposure to a harsh desert environment, marked by high ambient temperatures (up to 45°C), elevated UV index levels ( 11 during peak months), and high solar irradiance (over 1000 W/m²). Performance analysis under standard test conditions (STC) reveals a 29.61% reduction in maximum power output (Pmp), a 5.63% decline in short-circuit current (Isc), and a fill-factor decrease to 58.86%. Forecasting analysis indicates that, at the observed degradation rate, the module’s power output is projected to fall to 53.29 W by year 25, well below warranty expectations. Notably, the module reached the 80% power rating threshold within 13 years, significantly earlier than the 25-year lifespan claimed by manufacturers. Electroluminescence (EL) imaging identifies significant inactive regions caused by microcracks and interconnect failures, while visual inspection shows encapsulant yellowing and frame corrosion, consistent with UV and thermal degradation effects. These results highlight the necessity for PV modules with improved UV and thermal stability to maintain durability and efficiency in extreme climates, supporting the sustainable deployment of solar energy in desert regions.