Impact of Climate Variability on Solar Photovoltaic Performance Across Indian States: A Multi-Decadal Resource and Environmental Risk Assessment

Solar photovoltaic (PV) energy is a key component of India’s transition towards a low-carbon energy system. However, the long-term reliability of PV generation is increasingly influenced by climatic and environmental variability. This study investigates the impacts of multi-decadal changes in solar irradiance, atmospheric aerosol loading, cloud cover, and surface temperature on PV performance across fifteen Indian states over the period 1990–2023. Satellite observations, reanalysis datasets, and national energy statistics were integrated with PV performance modelling to quantify historical losses. A state-level panel regression model was employed to estimate the sensitivity of PV yield to climatic drivers. Results reveal climate-induced performance reductions ranging from approximately 10% to 21%, with aerosols and rising temperatures emerging as dominant stressors. Future projections under CMIP6 climate scenarios indicate further yield reductions by mid-century, particularly under high-emission pathways. A composite vulnerability index identifies northern and urbanized states as highly exposed to climatic risks. The findings emphasize the importance of climate-responsive solar planning, adaptive technologies, and region-specific policy interventions to sustain long-term solar energy performance in India.