Space is the future for renewable energy

SCIENTISTS and engineers agree we can solve the whole issue of net zero by using our ability to develop technology to replace fossil fuels.

Doing this right means we could avoid damaging our beloved landscapes with solar farms and wind turbines. So, it’s a win-win if we can remove the big old polluting power stations without causing damage elsewhere.

On this basis, it’s attractive to put the infrastructure in space because the visual impact is just a twinkle in the sky, causing no issues for anyone. It is becoming feasible too; the European Space Agency’s Solaris programme is studying space-based power; the Chinese have a target to get a demo running by 2028; and a US Caltech prototype beamed the first energy back to Earth this year. Space-X are testing Starship, which is a “tipping point” technology capable of lifting 100 tonnes into space on a reusable rocket.

But getting satellites with solar panels several kilometres wide (the scale needed) into space will need thousands of launches of Starship, over decades. It needs a fleet of rockets and a fleet of robotic orbital ships that haven’t been designed yet to assemble the satellites.

Back on Earth, the receivers to collect the energy that is beamed back will be 2-10km wide. Transmission losses may be 40% or as high as 90% according to the University of Portsmouth, requiring 10 times as many satellites. We just don’t know.

This requires a lot of infrastructure on the ground. No one will volunteer to live next door to a space port nor will they want these in our unspoiled countryside.

A big argument for space power is the constant supply, day and night, compared to renewables that need to be stored. For this nuclear fusion is the main competitor and, interestingly, both have become credible in the last three years, but only one needs space ports.

Considering all this, both space power and nuclear fusion may have an important role providing a small proportion of demand, as nuclear energy does today, but it’s not competitive with even the current range of alternative renewable technologies and storage.

What’s more, while we wait until 2050 or later to get space energy up and running, we may have truly solved the terrestrial storage issue with better batteries, hydrogen and new types of energy stores.

Maddie Evans