The idea of space-based solar power (SBSP) – using satellites to collect energy from the sun and “beam” it to collection points on Earth – has been around since at least the late 1960s. Despite its huge potential, the concept has not gained sufficient traction due to cost and technological hurdles.
Transferring energy collected in space to the ground requires wireless power transmission. Using microwaves for this minimises the energy lost in the atmosphere, even through cloudy skies. The microwave beam sent by the satellite will be focused towards the ground station, where antennas convert the electromagnetic waves back into electricity. The ground station will need to have a diameter of 5 km, or more at high latitudes. However, this is still smaller than the areas of land needed to produce the same amount of power using solar or wind.
This article explores the numerous designs have been proposed since the first concept by Peter Glaser in 1968, the national and international interest is SBSP, and the associated challenges and risks.