Europe Is Considering a Major Investment in Space-Based Solar Power


According to the head of the European Space Agency (ESA), Europe is exploring the development of space-based solar power to boost its energy independence and lower greenhouse gas emissions.

"It will be up to Europe, ESA and its Member States to push the envelope of technology to solve one of the most pressing problems for people on Earth of this generation," said Josef Aschbacher, director general of the space agency, an intergovernmental organization of 22 member states.

In the past, the space agency hired British and German consultancy companies to do studies on the costs and advantages of creating space-based solar power. To give European policymakers technical and programmatic knowledge, the ESA published the studies this past August.

Aschbacher will propose his Solaris Program to the ESA Council in November. Aschbacher has been trying to increase support for solar energy from space in Europe as a route to energy de-carbonization. This council determines the budget and priorities for ESA. The construction of the solar power system would start in 2025, according to Aschbacher's proposals.

The Positives. Space-based solar energy is simple to understand conceptually. Solar energy is captured by satellites orbiting high above the Earth's atmosphere. The satellites would then transform that energy into current and transmit it back to Earth via microwaves, where it is captured by photovoltaic cells or antennas and transformed into electricity for homes or businesses. There is no night or cloud cover to impede collection, and the solar incidence is significantly higher than in northern latitudes of the European continent, which are the main advantages of collecting solar energy from space as opposed to the ground.

The program proposes enormous installations in geostationary orbit that could supply between 25% and 30% of the yearly electricity demand for Europe, which is now estimated to be over 3,000 TWh. These technologies would be expensive to develop and implement, costing hundreds of billions of euros.

Why will it cost so much? Because it would take a constellation of many enormous satellites situated 36,000 kilometers from Earth to enable space-based solar power. Each of these satellites would be 10 or more times heavier than the 450 metric ton International Space Station, which took over a decade to build in low Earth orbit. The final launch of these satellites' components would need hundreds or, more likely, thousands of heavy lift rocket missions.

"Using projected near-term space lift capability, such as SpaceX’s Starship, and current launch constraints, delivering one satellite into orbit would take between 4 and 6 years," Frazer-Nash, the British Firm involved in the study states. "Providing the number of satellites to satisfy the maximum contribution… to the energy mix in 2050 would require a 200-fold increase over current space-lift capacity."

The Negatives. Although the idea of solar energy generated in space is intriguing, it is not without its detractors. Elon Musk, who one might expect supporting a system that is in space and produces solar energy, is one of the biggest opponents.

"It's the stupidest thing ever," he said, several years ago. "If anyone should like space solar power, it should be me. I've got a rocket company, and a solar company. I should be really on it. But it's super obviously not going to work. It has to be better than having solar panels on Earth. With a solar panel in orbit, you get twice the solar energy, but you've got to do a double conversion: Photon to electron to photon, back to electron. What's your conversion efficiency? All in, you're going to have a real hard time even getting to 50%. So just put that solar cell on Earth."

He is not alone either. Physicist Casey Handmer identified four cost drivers in an online analysis that will render space-based solar power unaffordable: transmission losses, heat losses, logistics expenses, and a space technology penalty. According to Handmer, the cost of space-based solar energy is at least "three orders of magnitude" more than energy sources on Earth.

"I can relax assumptions all day," Handmer wrote. "I can grant 100 percent transmission efficiency, $10/kg orbital launch costs, complete development and procurement cost parity, and a crippling land shortage on Earth. Even then, space-based solar power still won’t be able to compete. I can grant a post-scarcity fully automated luxury communist space economy with self-replicating robots processing asteroids into solar panels, and even then, people will still prefer solar panels on their roof."

Perhaps the conflict in Ukraine and the dearth of Russian natural gas will spur this project along. A major space agency trying out a technique that has been considered science fantasy for literally decades would be good. But there are many obstacles to overcome and a lengthy time frame.

The Earth will probably get its energy from space in the future. But will that happen in the next century or even later? Without a doubt, the most comprehensive and ambitious project the European Space Agency has ever done would be space-based solar power. It would undoubtedly be the Apollo program of the twenty-first century. Only much bigger.



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