Some researchers believe the Sahara could, in theory, be transformed into a massive solar power plant. A project of that scale could generate enough electricity to meet nearly four times the world’s current energy consumption. Spanning more than 8.5 million square kilometers, this North African desert is the largest on Earth. Temperatures can reach 55 °C. Several projects have already proposed installing solar panels there, with the goal of supplying electricity to millions of European homes. Still, major obstacles remain.
The Sahara Desert is not likely to be covered with solar panels anytime soon. Because of their dark color, panels absorb far more heat than sand. This can further warm the surrounding environment and reduce air pressure. Heat is reflected toward space, where it condenses the moisture present there. Studies suggest that a solar farm in the Sahara could increase monsoon rainfall. Greater humidity in the Sahara could also mean less rain in the tropics and drought in the Amazon region. Researchers also believe that large-scale solar deployment in the Sahara could disrupt wind circulation.
A solar power project in the middle of a desert can have serious environmental consequences. Installing solar panels could damage natural areas and disturb fragile ecosystems. At that point, the issue would no longer be only about renewable energy, but also about the survival of wildlife and plant life. A desert covered in solar panels would affect the climate. According to researchers, ground temperature and wind cycles would be disrupted. A huge solar farm would also increase the carbon footprint and require a large amount of raw materials. Finally, removing sand from solar panels would require a great deal of water, a resource that is already rare and precious in desert regions.
The photovoltaic cells used in solar panels become less efficient at extreme temperatures. Their output would therefore be less impressive than it seems at first glance. Covering a desert with solar panels would also be an economic challenge, with electricity costs reaching millions of euros. Deserts also lack the infrastructure needed to maintain panels, especially after a sandstorm. That would mean investing again in cleaning robots capable of covering hectares of panels. On top of that, there is the problem of sending electricity to other countries, since deserts are so vast. A consortium from the Innova MicroSolar project favors smaller-scale production instead.

source