The Desertec Foundation which intends to develop massive solar generation capacity in the Sahara as well as a direct current supergrid to bring the power to Europe has published the Desertec-Atlas to explain the concept of desert power.

Because the Earth's surface has warmed by about 0.8 ° C since 1900, radiation from the earth's surface (396 W/m²) has increased by about 5 W/m². Absorption from the atmosphere by the surface has increased by about the same amount. The result is a net energy inflow of about 1 W/m², which compared to the energy 0.03 W/m² generated directly by humans, is significant.

Energy from the sun

Radiation from the sun 341 W/m²
Absorbed by atmosphere -78 W/m²
Reflected by clouds and aerosols -79 W/m²
Reflected by Earth's surface -23 W/m²
Absorbed by Earth's surface 161 W/m²

Energy loss from the Earth's surface

Radiation from Earth's surface -396 W/m²
Convection from surface -17 W/m²
Evapotranspiration from surface -80 W/m²
Total loss from surface -493 W/m²

Net balance:

Radiation from sun 161 W/m²
Absorbed from atmosphere 333 W/m²
Total absorbed by surface 494 W/m²
Total lost by surface 493 W/m²
Net absorption 1 W/m²
Human generated 0.03 W/m²

Approximately 161 W/m² of direct solar radiation is absorbed by the Earth's surface. 333 W/m² are absorbed by the Earth's surface from the atmosphere for a total of 494 W/m².

The Earth's surface radiates about 396 W/m². Together with evapotranspiration (80 W/m²) and convection (17 W/m²) the Earth's surface loses 493 W/m².

The net result is an increase in absorption of about 1 W/m².