Growing crops at solar farms increases panel efficiency

A recent study led by Cornell University has found that growing commercial crops at solar farms not only increases food production, but also improves solar panel performance and longevity. These findings highlight the importance of developing and employing new technologies at a critical time for agricultural production, as global food demands are expected to rise by 50 percent by mid-century to feed up to 10 billion people, while the development of renewable energy sources is urgently needed to mitigate the impact of climate change. 

“We now have, for the first time, a physics-based tool to estimate the costs and benefits of co-locating solar panels and commercial agriculture from the perspective of increased power conversion efficiency and solar-panel longevity,” said lead author Henry Williams, a doctoral student in Sustainable Solar Development at Cornell.

“There is potential for agrivoltaic systems – where agriculture and solar panels coexist – to provide increased passive cooling through taller panel heights, more reflective ground cover and higher evapotranspiration rates compared to traditional solar farms,” added senior author Max Zhang, an expert in Energy and the Environment at the same university. “We can generate renewable electricity and conserve farmland through agrivoltaic systems.”

In New York, for instance, nearly 40 percent of utility-scale solar capacity has been developed on agricultural lands, and 84 percent of land considered suitable for utility-scale solar development is agricultural. 

According to the scientists, solar panels mounted over vegetation have lower surface temperatures than those built over bare ground. For instance, solar panels mounted four meters above a soybean crop showed temperature reductions by nearly 10 degrees Celsius compared to those mounted a half-meter above bare soil. This cooling effect – which is more significant than that induced by greater panel height – not only adds to solar panel efficiency, but also leads to improved solar panel lifespan and, thus, major long-term economic potential.

“As you decrease the solar panel operating temperature, you can increase efficiency and improve the longevity of your solar modules. We’re showing dual benefits. On one hand, you have food production for farmers, and on the other hand, we’ve shown improved longevity and improved conversion efficiency for solar developers,” Williams concluded.

The study is published in the journal Applied Energy.

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By Andrei Ionescu, Earth.com Staff Writer

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