Space-based solar power: Powering the earth

Solar Power In Space

Around 1.2 billion people in the world don’t have access to electricity. A further 1 billion don’t have reliable electricity networks needed for powering medical equipment and other basic requirements, according to a United Nations Foundation report.

“Solar power satellites introduce the profound capability to send clean, constant energy nearly anywhere in the world, which would be huge for places that don’t currently have reliable electricity,” says Paul Jaffe, a spacecraft engineer at the U.S. Naval Research Laboratory in Washington, D.C.

Why solar panels in space are a good idea?

Of all the energy sources available on earth, the sun is as good as it gets. However, on earth, solar power is generally reduced by night, cloud cover, atmosphere and seasonality.

Solar panels also take up a lot of land, and around 30% of all incoming solar radiation never makes it to ground level.

“To power the entire world with solar power, we would need to cover an area that’s 92% the size of Nevada in solar panels, and that’s not even counting the batteries,” says Lewis-Weber in his published a paper, New Space.

In space the sun is always shining, there is no weather to compete with and there’s no atmosphere to reduce the intensity of the sun’s rays. In addition, the light that would reach the panels would be 27% brighter, as it would not need to filter through the atmosphere.

How will space-based solar power work?

Self-assembling satellites are launched into space, along with reflectors and a laser transmitter or microwave.

The reflectors or mirrors would spread over a vast area of space, directing light radiation onto solar panels.

The solar panels will then convert the light into either a laser or microwave and send undisturbed power down to earth. Power-receiving stations on earth would collect beams and add it to an electric grid.

space solar power

The Challenges of space-based solar power

Powering the earth would require a LOT of solar panels, and launching all of these up into space is by no means cheap.

A single SpaceX launch costs around $60 million. This means it could cost tens of trillions of dollars to send up a meaningful number of solar power satellites.

Paul Jaffe, who works on space-based solar panels at the U.S. Naval Research Lab, says, “The launch cost is one of the most influential factors in determining the cost of space solar.”

“Without that cost coming down, or using some alternate means to put the spacecraft in place, it’s not going to compete [with fossil fuels] on price”, he added.

In conclusion, space-based solar panels remain a tempting possibility in providing reliable and clean energy to people in in developing countries, or to disaster-stricken areas, without having to rely on the traditional grid to a large local power plant.


Image Source: Courtesy Artemis Innovations