The theory that solar farms can act as “massive heat banks” and even spoil food crops has been challenged by the findings of a new international scientific study that has shown PV arrays to have a cooling effect on the land surrounding them, reducing nearby surface temperatures by up to 2.3°C.
The team of scientists, from the UK, China and the US used satellite technologies to gather land surface temperature data for two large-scale projects in arid locations: the 300MW Stateline solar farm in California, and the 850MW Longyangxia solar park in China.
A paper published by the journal Renewable and Sustainable Energy Transition found that the panels produced “cool islands” that reduced the surrounding land surface temperature by up to 2.3℃ at 100 metres away, with the cooling effects reducing exponentially to 700 metres.
The team hypothesised that this cooling effect was due to the solar panels shading and insulating the land surface, as well as energy is converted into electricity by the solar panels. And it determined the impact of this might be good or bad or inconsequential, depending on the location and surrounding ecosystem.
“Most studies examine the impacts of land-use change for solar parks inside the site boundaries,” said Dr Alona Armstrong, co-lead author from Lancaster University. “Here, we found a temperature effect that is evident up to around 700 metres away, suggesting that ecological processes may also be impacted.
“This heightens the importance of understanding the implications of renewable energy technologies on the hosting landscape – we need to ensure that the energy transition does not cause undue damage to ecological systems and ideally has net positive consequences on the places where we build them.”