Scientists unearth a consequence of solar panels in the Sahara…
While the black surfaces of solar panels absorb most of the sunlight that reaches them, only a fraction (around 15%) of that incoming energy gets converted to electricity. The rest is returned to the environment as heat. The panels are usually much darker than the ground they cover, so a vast expanse of solar cells will absorb a lot of additional energy and emit it as heat, affecting the climate.
If these effects were only local, they might not matter in a sparsely populated and barren desert. But the scale of the installations that would be needed to make a dent in the world’s fossil energy demand would be vast, covering thousands of square kilometers. Heat re-emitted from an area this size will be redistributed by the flow of air in the atmosphere, having regional and even global effects on the climate. […]
Covering 20% of the Sahara with solar farms raises local temperatures in the desert by 1.5°C according to our model. At 50% coverage, the temperature increase is 2.5°C. This warming is eventually spread around the globe by the atmosphere and ocean movement, raising the world’s average temperature by 0.16°C for 20% coverage, and 0.39°C for 50% coverage. The global temperature shift is not uniform though – the polar regions would warm more than the tropics, increasing sea ice loss in the Arctic. This could further accelerate warming, as melting sea ice exposes dark water which absorbs much more solar energy.
