For more than a century, we’ve dreamed of sending huge solar arrays into space and beaming their energy down to earth. Now, that dream is beginning to become a reality.
Despite the potential benefits of space-based solar power, however, there are many challenges. One is the environment out in space, which could damage panels and degrade them more quickly than those installed on Earth.
Solar Panels
For centuries, people have dreamed of sending huge arrays of solar panels into space and beaming their energy down to earth. Such a scheme would provide a virtually unlimited supply of clean, renewable electricity for our planet.
While some solar panels are already used to power homes and businesses, many more have been designed specifically for space use. The solar cells, or photovoltaics, are a tiny square of silicon covered in glass or plastic that absorbs the sun’s light and converts it into electricity.
To make solar power more efficient, solar cells are typically combined into strings or panels that produce a desired output voltage and current capability. Often, the strings of cells are connected in series to boost voltage or in parallel to increase current.
Unlike laser beams, which can be blocked by clouds, sunlight emitted from a solar array can travel through the atmosphere without losing much of its power. This can be transmitted to a ground station on the surface of Earth, which is then able to turn the microwaves into electricity for the grid.
Satellites
Solar power satellites collect sunlight and beam it back to Earth, converting it into energy and sending it back into the grid. This could be a big boost for our planet’s energy needs.
Satellites have two main parts: an antenna that lets them send and receive information, and a power source, usually solar panels. They may also have cameras, telescopes and sensors.
The exact way they work depends on their purpose. For example, many NASA satellites carry cameras that point toward Earth to gather information about our world. Other satellites face away from Earth to explore the solar system and universe.
In order to send their signals from space to earth, communication satellites must have antennas that increase the strength of the signal and retransmit it to the ground. Most telecommunications satellites use a large array of radio transmitters, each with a bandwidth of tens of megahertz.
Orbiting Power Plants
A space-based solar power plant (SBSP) is a power system that uses satellites to collect sunlight and beam it back to Earth. This is a much more efficient way to harness the sun’s energy than on Earth, where it has to be reflected by the atmosphere.
The satellites would be placed in geostationary orbit and have photovoltaic panels that capture the sunlight. They then turn the energy into microwaves and beam it to a receiver on the ground.
These satellites would be able to generate about two gigawatts of power each, equal to the energy output of a nuclear power plant.
Proponents of the technology say it can be used to power entire regions on the planet without using fossil fuels, and that it can also help clean up our aviation emissions.
The technology could be deployed as early as the 2030s. However, there are some hurdles to overcome, including the need to build many satellites and the potential for anti-satellite missile attacks.
Technology
Throughout history, new technology has been used to solve problems and create better ways of living. However, some of these technologies can be harmful and disrupt the social structure.
A potential solution to the energy crisis is space-based solar power (SBSP). The concept involves harvesting energy from large satellites that orbit high above the Earth, turning it into radio waves and beaming them back down to earth where they can be converted into electricity.
The satellites would be powered by solar panels that collect the sun’s rays, and a central transmitter could continually transmit these rays to Earth. The satellites would be able to move in a geostationary orbit about 36,000 km above the Earth, and the rays would be converted into microwaves that can travel through the atmosphere without being blocked by clouds.
But getting the power to earth will be a challenge. A major obstacle is getting enough of these satellites into orbit, but it also means overcoming the loss of energy that occurs during the conversion process.