Climate change is exerting a significant impact on solar energy generation in the U.S., according to a recent study conducted by climate and energy analytics company Sunairio.

Outdated pre-construction energy models are typically used to assess the risk of solar production neglect the influence of climate trends, resulting in overestimates of up to 12% in solar production from new projects. The new analysis conducted to quantify the influence of climate change on solar asset underperformance in the U.S. was based on a sample of 100 utility-scale solar sites nationwide. Forward-looking production estimates prepared for each site over a 15-year period considered current and expected changes in local weather patterns influenced by climate change.

Positive temperature trends and regional but broadly negative global horizontal irradiance (GHI) measurement trends are indicated. Source: Sunairio

Results were compared to industry-standard methods that use historical weather data without adjusting for climate trends, revealing that the current average production gap across all sites is 2% and is expected to increase to 5% by 2034. On an individual site basis, the difference between using conventional backward-looking analysis and a climate-change-aware simulation can be as high as 5% currently and 12% by 2034, a discrepancy in production estimates that can significantly impact project returns for solar project owners.

Strong negative trends are projected for the midwestern and southeastern regions of the U.S., with weaker negative trends in store for the eastern region. The research underscores the need to incorporate climate modeling insights into solar production risk assessment to boost investor confidence and enhance grid reliability.