Large-scale wind and solar farms could make the Sahara literally green


In Maryland, researchers used a climate model to show that the installation of large-scale wind and solar power generation facilities in the Sahara could cause more local rainfall, particularly in the neighboring Sahel region. This effect, caused by a combination of increased surface drag and reduced albedo, could increase coverage by vegetation, creating a positive feedback that would further increase rainfall.

Wind and solar farms offer a pathway to clean, renewable energies. However, these farms would significantly change land surface properties, and, if sufficiently large, the farms may lead to unintended climate consequences.

Using a climate model with dynamic vegetation, researchers showed that large-scale installations of wind and solar farms covering the Sahara lead to a local temperature increase and more than a twofold precipitation increase. The resulting increase in vegetation further enhances precipitation, creating a positive feedback that contributes almost 80 percent of the precipitation increase for wind farms.