Wind and solar farms appear to enhance local rainfall and also vegetation cover in the Sahara Desert, a new study reveals.
The results suggest that, compared to power generation involving fossil fuels, the impact of wind and solar technology on regional climate would raise global temperatures minimally, yielding overall benefits.
Models suggest that largescale wind and solar farms, which are being evaluated to replace traditional power generation, have the potential to produce climate change at continental scales.
Yet, so far, the way wind and solar farms – the panels and infrastructure of which would cover wide swaths of land if more widely implemented – could alter vegetation and regional climate processes have not been thoroughly evaluated.
Here, Yan Li and colleagues sought to more comprehensively explore the impact of solar and wind farms in the Sahara desert and the neighbouring Sahel region, areas particularly desirable for such farms because of their vastness and lack of inhabitants.
Using a combination of experiments and modelling, they report that both types of farms ultimately increase local precipitation and plant growth.
Wind farms mix warmer air from above, which creates a feedback loop whereby more evaporation, precipitation and plant growth occurs.
The data suggest that wind farms can double the amount of daily precipitation.
Solar panels, on the other hand, reduce surface albedo (the reflection of light) and thus trigger a positive “albedo-precipitation-vegetation” feedback that leads to precipitation increases of about 50%, the authors report.