Space-based solar power may be one step closer to reality, thanks to this key test (video)
Unlike solar panels on Earth, a solar power plant in space would provide a constant power supply 24/7.
![A test of a wireless power transmission technology designed for solar power transmission from space.](https://cdn.mos.cms.futurecdn.net/ezXE7xqF44Ed7eNKFkkzsM-320-80.jpg)
A first-of-its-kind lab demonstration shows how solar power transmission from space could work.
The demonstration, carried out by U.K.-based startup Space Solar, tested a special beaming device that can wirelessly transmit power 360 degrees around. That would be important for a potential future space-based power station, as its position toward the sun and Earth would change over the course of each day due to our planet's rotation.
The demonstrator is a key component of the CASSIOPeiA space-based solar power plant concept that is being developed by Space Solar. The company envisions that CASSIOPeiA could be in space within a decade, providing gigawatts of clean energy much more efficiently than solar plants on Earth.
Related: Can space-based solar power really work? Here are the pros and cons.
"We’re thrilled to be able to demonstrate the next phase in the development of our technology," Martin Soltau, co-CEO of Space Solar, said in an emailed statement. "Space Solar's successful testing of [the 360-degree power-beaming technology] marks a pivotal moment in our mission to revolutionize space-based solar power."
CASSIOPeiA would be placed in geostationary orbit, a path about 22,000 miles (36,000 kilometers) above Earth in which the orbital velocity of a satellite matches the speed of Earth’s rotation. As a result, a spacecraft at this altitude appears suspended above a fixed region on Earth.
While the demonstrator used in the lab experiment was only 1.5 feet (0.5 meters) wide, CASSIOPeiA would ultimately be a vast modular structure some 1.1 miles (1.7 kilometers) across. The plant, consisting of large, lightweight solar panels and a set of mirrors collecting sunlight, would be assembled in orbit by robots, and would require 68 launches of SpaceX's next-gen Starship megarocket to deliver all its components to space.
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The recently tested component will ensure that the giant satellite has a constant view of both Earth and the sun in order to provide clean energy 24/7, unlike solar plants on Earth, which only work during daytime and get affected by bad weather.
The intermittent nature of terrestrial renewable power generation is a major concern, as other types of energy generation are needed to ensure that lights stay on during unfavorable weather. Currently, electrical grids rely either on nuclear plants or gas and coal fired power stations as a backup, but both technologies have their problems. Nuclear power plants generate potentially dangerous waste, and gas and coal power stations are a source of greenhouse gas emissions, which the world is trying to eliminate in order to stop the progression of climate change.
"This successful test is a really important milestone on the way to making space-based solar power a reality," Paul Bate, the chief executive of the U.K. Space Agency, which supports the project, said in a separate statement. "Safe, wireless, 360-degree energy transmission is a game changer and demonstrates the U.K.’s leading position in this new energy revolution, quite literally harnessing the power of space to benefit life on Earth."
Electrical power generated by CASSIOPeiA would be converted into high-frequency radio waves, which would be beamed down to Earth, where they would be transformed back into electrical power. The demonstration also tested a precision pointing system that would ensure the waves don’t pose any safety risk to humans living around the receiving station.
A single CASSIOPeiA plant could power more than a million homes, researchers estimate. Solar power plants in space, although difficult to build, would produce energy 13 times more efficiently compared to those on Earth, as their view of the sun is not obscured by atmospheric gases.
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![Tereza Pultarova](https://cdn.mos.cms.futurecdn.net/DtBEJHEfFqdaPxGrpMxNyX.jpg)
Tereza is a London-based science and technology journalist, aspiring fiction writer and amateur gymnast. Originally from Prague, the Czech Republic, she spent the first seven years of her career working as a reporter, script-writer and presenter for various TV programmes of the Czech Public Service Television. She later took a career break to pursue further education and added a Master's in Science from the International Space University, France, to her Bachelor's in Journalism and Master's in Cultural Anthropology from Prague's Charles University. She worked as a reporter at the Engineering and Technology magazine, freelanced for a range of publications including Live Science, Space.com, Professional Engineering, Via Satellite and Space News and served as a maternity cover science editor at the European Space Agency.
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Classical Motion Reality? How many car loads of coal will it take to put it up there?Reply
I love solar power. I used it for years and even suffered thru many panel disasters from eagle nests, buffaloes, and bullet holes. But it is limited to relatively small power and non-life conditions.
Much better panels and batteries are needed before solar can compete. Be convenient and dependable. One can solar power his house now, off the shelf, but the battery cost and maintenance eats up any advantage. Just like the cost and bother with an EV battery.
However we have great older tech that can be used to solar heat water and relieve some grid load. And it really is free. So, no one uses it. -
Ken Fabian We'll have clean energy or else fail on climate and face climate induced economic disasters that may make space solar even harder to achieve, long before anyone can attempt it. The ability to aim beamed power better has not changed how difficult and expensive such an option would be.Reply
Solar panels right now are excellent and low price - much lower and the price is approaching zero; the panels are no longer the costly part. Probably why 3/4 of all new electricity generation added globally is now solar - because most energy businesses don't really care about global warming. Production of solar is expected to reach 1 TW per year (double current production) before the end of next year - and investments in new solar factories globally is exceeded by investments in battery factories.
Continent wide (and possibly intercontinental) transmission lines, growth of battery storage in the grid and in homes and businesses plus the use of demand management - avoiding the high cost energy and taking advantage of the low cost by changing industrial processes and smart scheduling. And vehicle to home and grid from growing numbers of plugged in EV's - that with smart systems will be a lot more than simple sources of demand. A lot is happening that will make a big difference, with alarmist economic fear of shifting to renewable energy dissipating in the face of it.
Batteries keep getting better - eg CATL releasing new large scale containerised batteries with 30% improvement on energy density and significantly longer life. Apparently investing in science and R&D makes for better batteries - who'd have thought?
Pumped hydro is already gaining significant investment - something that wasn't going to happen until there was a lot of investor confidence that wind and solar would continue to grow enough to need long, deep storage. And there are options for cold climates, such as Finland is deploying - interseasonal heat storage for district heating. A lot of wind coming on line there plus hydro, plus nuclear as well as clever use of waste heat for district heating.
We are better placed than ever to build up low/zero emissions energy supply to displace fossil fuels - Biden's IRA in the US is only possible because alternatives have become low cost enough; even a decade ago it would have struggled. -
Classical Motion It's not the cost of panels. It's the efficiently. Not only of the final product, the natural states for these rare earths are not rare. But they are very diluted. Requiring very inefficient mining and processing. More emissions. Same with batteries.Reply
1 TW of solar power? Just in 2023, China added 37 TW of coal fire. 2024 will be higher. Not to mention India who has a higher demand.
The 3rd richest man in Asia is an Indian coal broker. India has a cabinet post for coal.
In the next 10 years, multiples of all man's combined previous emissions will be added. You ain't seen nothing yet. -
Jan Steinman "Houston, we have a problem. We just microwaved Des Moines."Reply
… tested a special beaming device that can wirelessly transmit power 360 degrees around. That would be important for a potential future space-based power station, as its position toward the sun and Earth would change over the course of each day due to our planet's rotation.
Wouldn't that be terribly inefficient? Seems to me you need as tight a beam as possible. Energy spread over 359° is energy that is not going to the 1° target, no?
Also, energy follows an inverse-square law with distance. Geosync orbit is terribly convenient, but so far away. If Elon can get Starlink into homes via low-Earth-orbit satellites, why can't we aim those power microwaves with such precision? -
Ken Fabian @Classical Motion - your China coal plant construction is way overstated - by about 350X. Maybe you read GW as TW.Reply
China approved 106 GW of new coal plants last year - which is, of course, too many.
But China hasn't broken it's climate pledges yet - global agreements granting China a 2060 target for zero emissions, an extra decade for economic development and lifting people out of poverty - agreements brokered by people who continue to disparage renewable energy. The amount of solar added last year was about double that in GW power terms - ie about 40% of that in GWh 20% capacity factor terms. And the solar equipment they export underpins emissions reductions in other nations.
That is a huge amount of solar additions - more than the rest of the world and about double the year before - with investment in solar factories set to underpin greatly increased installed capacity in the near future. One more doubling (expected within 2 years) and it exceeds coal additions. And adding lots of solar starts undermining the cost effectiveness of coal plants by gutting the hours of high daytime demand coal needs to be economic - a defacto carbon price that will go on to suppress the viability of coal. -
Unclear Engineer https://www.smithsonianmag.com/smart-news/since-2016-80-percent-of-global-co2-emissions-come-from-just-57-companies-report-shows-180984118/Reply -
Ken Fabian
I think they are saying they can sustain accurate aim on one spot from a rotating space installation.Jan Steinman said:"Houston, we have a problem. We just microwaved Des Moines."
Wouldn't that be terribly inefficient? Seems to me you need as tight a beam as possible. Energy spread over 359° is energy that is not going to the 1° target, no?
Also, energy follows an inverse-square law with distance. Geosync orbit is terribly convenient, but so far away. If Elon can get Starlink into homes via low-Earth-orbit satellites, why can't we aim those power microwaves with such precision?
Yes, the geosync orbit is a long way compared to low orbit. And there will be operational satellites crossing between.
I don't expect anything to come of it but the question that always comes to my mind when space based solar gets talked about is - what makes putting the solar in space better than keeping it on the ground and beaming power to space and then back down somewhere else? I suppose the answer is beamed energy transmission is very lossy - doing it once is poor enough. Doing it twice (or three times for a low orbit system that beams up, over to another space receiver and down again) is too much loss. -
Jan Steinman
The solar panels in space get a lot more power from the Sun than terrestrial solar panels, because the atmosphere absorbs and dissipates the solar energy.Ken Fabian said:the question that always comes to my mind when space based solar gets talked about is - what makes putting the solar in space better than keeping it on the ground
Then, it is used to power a tight microwave beam, which at certain frequencies, passes through the atmosphere with much less resistance than sunlight does.
No one is talking about collecting sunlight on the ground, beaming it to a satellite, then beaming it back down. It's all about the greater efficiency of collecting sunlight at the satellite, above the atmosphere. -
Ken Fabian Jan, I'm talking about it because I haven't heard anyone else. We are getting enormous amounts of solar on the ground way, way cheaper than any we install in space. A way to send it to distant locations - say, up from a sunny afternoon in one place and back down to somewhere hitting evening peak demand - is a potentially valuable application for the technology surely. But probably about as realistic as solar farms in space as a low emissions energy solution despite needing to put less stuff into space - ie not.Reply