The final frontier for solar power generation
The solar industry is rarely short of ambition; but perhaps the boldest idea of all is to harness energy from solar panels in space. While such panels have been used to power satellites for decades, pioneering companies are now working on plans to capture energy in orbit and beam it back to Earth.
“The sun always shines in space, so you get baseload power — 24/7 dispatchable baseload energy,” says Sam Adlen, co-CEO of British start-up Space Solar, which has designed technology for solar installations in space. He tells fDi that a solar panel in space will capture 13 times as much energy as a panel on Earth. “That’s what drives the really compelling economics.”
Space Solar plans to deploy satellites with enormous disc-shaped reflectors more than a kilometre in diameter. The reflectors, assembled robotically in space, would transmit energy via a microwave beam to receivers on the ground.
Space-based solar power could provide €180bn in net benefits to Europe
In 2022, a study commissioned by the European Space Agency found space-based solar power could provide €180bn in net benefits to Europe — mainly through reducing the cost of importing fossil fuels. The study projected that initial satellite systems would be cost-competitive with other renewable technologies and that costs would come down with economies of scale.
Adlen says the first pilots with space-based solar could deliver power to very remote places that cannot rely on conventional solar panels. During the long nights of the Antarctic winter, for example, ordinary solar installations are useless for polar scientists. They must instead run expensive and highly-polluting diesel generators to power their bases. Receiving solar energy from space could be a greener and more reliable alternative for these scientists operating at the end of the Earth.
Space Solar also agreed a deal last year to supply 30 megawatts of electricity from a pilot project to Icelandic utility Reykjavík Energy by the early 2030s. This would be followed by a larger scale system later in the decade.
Resource efficiency
Ultimately, Adlen insists space-based solar will make efficient use of land and materials through avoiding the need to “overbuild” capacity to ensure power is always available.
Earlier this year, UAE company Masdar announced a plan to deliver a continuous supply of baseload power through a solar and battery facility. The small print, however, is that ensuring 1 gigawatt of continuous supply requires 5GW of solar capacity, plus batteries with 19GW-hours storage capacity.
Adlen says space-based solar will require far fewer materials than terrestrial alternatives, partly because it negates the need for battery storage. Beaming power from satellites could therefore help mitigate some of the resource dilemmas that have accompanied the growing use of solar power. “This is an incredibly compelling option, both in terms of the economics that can be produced, but also the way it can work as part of the overall energy system,” he says.
The whole idea of beaming solar power from space might still sound like something out of science fiction. But, when considering how rapidly solar technologies have evolved in recent years, it would be unwise to bet against the ability of solar power to cross its final frontier.