How much solar energy would it take to power the entire world? If you filled a 1,270 by 1,270 km area with solar panels that operated at 20% efficiency, you could generate enough power. That’s only about 16% of the size of the Sahara Desert (0.3% the size of the Earth). Currently there are enough solar panels in the world to cover a 120 by 120 km area. While we’re still far away from a renewable powered world, we’re getting there faster and faster.