Europe is considering investment in the project for cosmic solar energy called SOLARIS to increase its energy independence and reduce greenhouse gas emissions, explained the head of the European Space Agency.

“It will be up to ESA, the European Union and their member states to advance these types of technologies and solve one of the most pressing human problems on Earth in this generation.”, Explain Josef Aschbacher, CEO of the space agency.

ESA has commissioned studies from consultancy groups based in the UK and Germany to assess the costs and benefits of developing solar power in space. The reports were released this week and will be key to the agency’s presentation of the Solaris project at its next board in November, where priorities and funding will be set for the same and future decisions on the technology.

SOLARIS: how space solar power would work

If Putin’s war in Ukraine can be of any use, it is the urgent need to definitely bet on alternative methods of energy production other than the burning of fossil fuels, which is driving the Earth and humanity into an unsustainable situation. This week we saw the latest advances in nuclear fusion and now we have another alternative with solar power as the protagonist.

The basic concept is pretty “simple” on paper. Satellites orbiting above the Earth’s atmosphere would collect solar energy and convert it into power. These would be sent to Earth via microwaves, where they would be picked up by photovoltaic cells or antennas and converted into electricity for residential or industrial use.

The advantages of harnessing solar energy in space rather than on Earth’s surface are well known. There are no nights or clouds which interfere with the collection of light reaching us from the Sun, and would also not be penalized by the latitude of the continent. The problem, as usual, is to put a project like SOLARIS into commercial practice.

Issues: $$$$$$$ and efficiency

The consultation reports commissioned by ESA address the technology development and funding needed to bring the space energy system online. Europe currently consumes around 3,000 TWh of electricity per year, and reports describe massive installations in geostationary orbit that could between a quarter and a third of this demand. The development and deployment of these systems would cost hundreds of billions of euros.

Creating a space-based solar power infrastructure would require a a constellation of dozens of huge satellites capturing sunlight located 36,000 km from Earth. Each of these satellites would weigh 10 times the 450 metric tons of the International Space Station. It would take more than a decade to put this device into orbit, and those needed for solar power would be larger and would have to be raised to a higher orbit.

One of the reports detailed that it would take “hundreds” or “thousands” of launches of a platform that does not currently exist to reach the maximum energy predicted for SOLARIS. The most advanced of the current ones, SpaceX, would have to increase its capacity 200 times to complete SOLARIS in 2050.

The project is attractive in itself, but there is no lack of criticism. SpaceX boss Elon Musk himself called the project “stupid”. “If anyone likes space solar, it should be me. I have a rocket company and a solar company. I really should be on it. But obviously it won’t work. With a solar panel in orbit, you get twice the sun’s energy, but you have to do a double conversion: photon to electron to photon, back to electron. What is your conversion efficiency? It will be very difficult to reach even 50 percent. So just put that solar cell on Earth«Musk said.

Even leading scientists are against it. Casey Handmer outlined four areas where costs make space solar prohibitively expensive: transmission losses, heat losses, logistics costs, and space technology penalties. According to Handmer’s estimate, solar energy from space is the least “three orders of magnitude” more expensive than terrestrial energy sources.

Reports commissioned by the European Space Agency do not address the main concerns of critics of solar power from space: cannot compete financially with Earth’s energy sources, including ground-based solar panels. Europa may be at a higher latitude than is ideal for solar power, and its landmasses are often cloudy. But even then, getting energy from space will require massive subsidies from European governments to achieve cost parity with terrestrial energy.

It all sounds like science fiction at this point. The engineering hurdles are huge, the investment very expensive, and the implementation timeline is long. But what will happen in a few decades? We’ll leave it there for your analysis and opinion.