Put solar panels in space has never been profitable, but there is something that motivates the current interest: its military use

The old idea of ​​collecting energy from the sun from space to transmit it uninterrupted to Earth has always collided with the huge costs and technological barriers that have prevented their deployment. Until now.

A global interest. Governments and companies around the world seem to have a renewed interest in space solar energy. The drastic drop in launch costs, thanks to the emergence of reusable rockets such as Spacex, could have cleared the main economic obstacle from the equation.

The necessary technology has also matured in parallel: solar panels are lighter and more efficient, and wireless energy transmission (microwave or laser) is more advanced. The same with robotics, which will be necessary to assemble the stations in orbit.

The military factor. As with any renewable project, the energy transition and emission commitments are the engine of this new effort. But behind the recent interests of the Chinese government or the pentagon there is something else: the military potential of space solar energy.

“The military utility of transmitting energy to land, aerial or maritime units is obvious,” He said to Spacenews Darpa’s tactical technology project manager Paul Jaffe. Transporting fuel to remote places with tank airplanes can be a usual practice, but “it is not a practical way to bring energy where we need it for defense purposes.”

In addition to DARPA, who has conversations with space solar energy startups and invests in the development of long -distance wireless energy transmission, the United States Air Force and Navy are also in garlic.

Pentagon projects. The Air Force Research Laboratory (AFR) actively develops space solar technology through its “Space Solar Incremental Demonstrations and Research” program.

Its flagship mission “Arachne” will prove in orbit a sandwich panel that converts sunlight into radiofrequency energy to transmit it to a terrestrial receptor. Led by Northrop Grumman, it is scheduled for this year with the explicit objective of providing energy to the forces and reducing the dependence of fuel convoys, which are more vulnerable.

For its part, the Naval Research Laboratory (NRL) integrated a module called PRAM into the X-37B secret space plane to prove the conversion of solar energy to microwave. Now the project is part of the space force.

What can we expect. Military interest is an important catalyst, and possibly one of the motivations behind the gigantic project of the Chinese Academy of Space Technology (CASC), which will display its first satellites in low orbit by 2028 and in geostationary orbit for 2030.

But in the coming years we will also see all kinds of commercial and space agencies, including the European Space Agency with its Solaris initiative, which focuses on viability studies. Despite these progress, the challenges are still considerable.

The two major doubts are profitability, in the case of commercial efforts, which will compete with the renewable energies deployed on land, increasingly profitable despite their intermittency. And security, which depends on the fact that you are issued at distances of hundreds or tens of thousands of kilometers are very precise. Maybe let’s see some “fried” birds along the way.