Deserts around the world have been expanding over the past several years due to the effects of global warming. The Sahara desert, which is the third largest desert on the planet, has been growing for a century and shows no signs of stopping. However, scientists from the University of Maryland have found that covering the Sahara in solar panels could possibly slow or reverse its expansion.

The Sahara desert’s dirt is dry, and therefore light in color. The ground’s light color causes it to reflect sunlight and heat away from it. The inside of the ground stays cool, because of the heat being reflected away. Since the ground’s temperature is low, there is very little heat from the ground being driven up into the atmosphere, which results in less precipitation. In other words, the Sahara’s dry, light-colored dirt prevents rain. As it rains less and less in the areas surrounding the Sahara, more of that land turns into desert.

A simple solution to this problem would be to darken the surface of the Sahara. A dark colored surface would encourage more rainfall, which could reverse the expansion of the desert. In order to achieve a darker desert, distinguished atmospheric scientist Eugenia Kalnay proposed the idea of using solar panels to cover the surface. The dark blue silicon panels would attract and retain a large amount of heat. Heat from the solar panels would travel up into the atmosphere and cause higher levels of precipitation. Additionally, a field of solar panels as vast as the Sahara desert could provide clean energy to millions.

A simulation of a solar panel-covered Sahara was run by one of Kalnay’s postdoctoral researchers to forecast the climate. It showed that if 20% of the Sahara desert’s surface was covered with solar panels, rainfall in the area would be about 1.5 times the amount that it is now. This would be more than enough rain to restart plant growth in many areas of the Sahara. The result would ultimately be a reverse of the expansion of the desert. A solar energy farm of that size would be about as large as the U.S. and would produce several times the amount of electricity that is being consumed around the world now. It would also cause an increase in rainfall and would generate huge amounts of energy in an eco-friendly way, making it a win-win solution.

Kalnay explained that the idea would sound like one out of a science fiction story “if the technology was not available.” She stated that a solar panel-covered Sahara “seems like a major solution for some of the problems that we have,” and that it is completely possible to build one today. The only thing that’s left to do is to start.