Degradation and projected lifetime of polycrystalline silicon photovoltaic modules after 10 years of field exposure in the Atacama Desert

This study quantifies degradation and projects the useful lifetime of polycrystalline silicon photovoltaic (PV) modules operating in the Atacama Desert, using I–V measurements taken after ten years of field exposure. The methodology included a visual inspection, outdoor I–V curve measurements, STC correction by IEC 60891 standard, and the evaluation of four key parameters Voc, Isc, Pmpp, and FF by comparing 2024 data with initial manufacturer specifications and ten long-term field studies conducted in comparable desert climates. Statistical analysis of the large-sample dataset (64 strings encompassing 1216 modules) yielded a mean degradation rate of 1.32%/year in Pmpp, corresponding to a projected lifetime of 15.15 years to the 80% power threshold, while a sensitivity analysis of realistic commissioning-time deviations in the initial power broadens the degradation rate to the range 0.87–1.58%/year and the associated lifetime to approximately 13–23 years. Common failure modes included cell cracking as an irreversible structural failure at the cell level, and environmental soiling as an optics-driven loss mechanism affecting the module frontsheet. These results emphasise the need for operation and maintenance strategies adapted to Atacama conditions and provide an STC-normalised benchmark that can support reliability assessment and warranty evaluation of PV plants in hyper-arid and other high-irradiance desert environments.