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 at least since the late 1960. Despite its enormous potential, the concept has not gained sufficient traction because of cost and technological barriers.
Can some of these problems be solved now? If so, SBSP could become a vital part of the global transition from fossil fuels to green energy.
We already collect energy from the sun. It is collected directly through what we generally call solar power. This includes different technologies such as photovoltaics (PV) and solar thermal energy. The sun’s energy is also harnessed indirectly: wind power is one example, because breezes are created by the uneven heating of the atmosphere by the sun.
But these green forms of energy generation have limitations. They take up a lot of land and are limited by the availability of sunlight and wind. For example, solar farms do not collect energy at night and collect less energy in winter and on cloudy days.
PV in orbit will not be limited by the onset of night. A satellite in geostationary orbit (GEO)—a circular orbit about 36.000 km above Earth—is exposed to the sun for more than 99% of the time over the course of a full year. This allows it to generate green energy 24/7.
GEO is ideal when energy needs to be sent from the spacecraft to an energy collector or ground station, because satellites there are stationary relative to Earth. It is estimated that 100 times more solar energy is available from GEO than humanity’s estimated global energy requirements by 2050.
Transferring energy collected in space to the ground requires wireless power transmission. Using microwaves for this minimizes the energy lost in the atmosphere, even when the sky is cloudy. The microwave beam sent by the satellite will be focused toward the ground station, where antennas convert electromagnetic waves back into electrical energy. The ground station would need to be 5 km in diameter or more at high latitudes. However, this is still smaller than the land areas required to produce the same amount of energy using solar or wind power.
Source: Techxplor
Can some of these problems be solved now? If so, SBSP could become a vital part of the global transition from fossil fuels to green energy.
We already collect energy from the sun. It is collected directly through what we generally call solar power. This includes different technologies such as photovoltaics (PV) and solar thermal energy. The sun’s energy is also harnessed indirectly: wind power is one example, because breezes are created by the uneven heating of the atmosphere by the sun.
But these green forms of energy generation have limitations. They take up a lot of land and are limited by the availability of sunlight and wind. For example, solar farms do not collect energy at night and collect less energy in winter and on cloudy days.
PV in orbit will not be limited by the onset of night. A satellite in geostationary orbit (GEO)—a circular orbit about 36.000 km above Earth—is exposed to the sun for more than 99% of the time over the course of a full year. This allows it to generate green energy 24/7.
GEO is ideal when energy needs to be sent from the spacecraft to an energy collector or ground station, because satellites there are stationary relative to Earth. It is estimated that 100 times more solar energy is available from GEO than humanity’s estimated global energy requirements by 2050.
Transferring energy collected in space to the ground requires wireless power transmission. Using microwaves for this minimizes the energy lost in the atmosphere, even when the sky is cloudy. The microwave beam sent by the satellite will be focused toward the ground station, where antennas convert electromagnetic waves back into electrical energy. The ground station would need to be 5 km in diameter or more at high latitudes. However, this is still smaller than the land areas required to produce the same amount of energy using solar or wind power.
Source: Techxplor
