The researchers from Kyushu University, Japan investigated how solar panels (PVs) installation can affect land temperatures surrounding the Kushida River Basin. It is in central Japan and encloses Matsusaka City, Taki Town, and Meiwa Town. To identify an aerial view of solar panels, the scientist employed a technique, convolutional neural networks (CNNs) and used a remote sensing tool to assess temperature changes. 

The model detects ground-mounted solar panels with the available data and then analyses how the nearby temperature affects their placement and types. Researchers studied a 767 km² area in Japan (mostly forests and farms) for 10 years. They used high-resolution photos and satellite data to track how solar panel installations affected land temperatures over time. 

The study revealed land near solar panels installed between 2013 and 2023 warmed by an average of 2.85°C, with a stronger effect in warmer months (up to 3.35°C) compared to colder ones (around 2.5°C). 

In addition, using statistical tools and models, such as Geographically Weighted Regression (GWR) and Ordinary Least Squares (OLS) models, spatial factors influencing temperature changes were identified. The analysis considered factors such as normalized difference vegetation index (NDVI), building density (BLD), population (POP), distance to rivers (WA), and elevation (DEM) as well as the size of the PV installations  

Quantifying the effect of the different factors on the warming of the PV area, the scientists found that elevation, building density, NDVI, PV area, and distance to waterways have the highest correlation with LST differences in suburban plant areas.

The study found the strongest warming effect from solar panels occurred in suburban industrial areas, suggesting factories may play a bigger role than other city activities. Interestingly, they also observed that installing solar panels in higher elevation areas or those with more vegetation helped to lessen the temperature increase.

Source Link: https://www.pv-magazine-india.com/2024/05/14/the-warming-effect-of-pv-on-land-surface-temperature/