More than 80 years ago, science fiction writer Isaac Asimov wrote Reason, a story about a solar energy collection station in deep space that delivered high-energy rays to receivers on Earth and Mars. Called space-based solar power (SSP), Asimov's idea didn't start to approach science fact in any meaningful sense until 1968...
...when Peter Glaser, an aerospace engineer with Apollo program experience working for the Arthur D. Little consultancy in Cambridge, MA, published a paper suggesting ways to construct SSP stations with separate solar collecting and giant dish-based microwave transmitters.
However, based on the pre-carbon-fiber, heavy-metal aerospace technologies of the day, studies by Nasa and the U.S. Department of Energy determined that a single solar-receiving satellite would weigh in excess of 80,000 tons, putting launch costs per power station way beyond consideration.
On January 3 2023, a SpaceX Falcon 9 rocket launched 114 small payloads, and right now...
...in a sun-synchronous orbit about 525 kilometers overhead, there is a small experimental satellite called the Space Solar Power Demonstrator One (SSPD-1 for short). It was designed and built by a team at the California Institute of Technology, funded by donations from the California real estate developer Donald Bren[.]
"To the best of our knowledge, this would be the first demonstration of actual power transfer in space, of wireless power transfer," says Ali Hajimiri, a professor of electrical engineering at Caltech and a codirector of the program behind SSPD-1, the Space Solar Power Project.
The Caltech team is waiting for a go-ahead from the operators of a small space tug to which it is attached, providing guidance and attitude control. If all goes well, SSPD-1 will spend at least five to six months testing prototype components of possible future solar stations in space.
[...] If it works out, in 30 years maybe there could be orbiting solar power fleets, adding to the world's energy mix. In other words, as a recent report from [British engineering consultancy] Frazer-Nash concluded, this is "a potential game changer."
SSPD-1 story originally spotted on The Eponymous Pickle.
Previously: Space-Based Solar Power Hardware Ready for Actual Testing in Space
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A Caltech solar power project has a payload on the latest Falcon 9 launch:
Solar power has become the lowest-cost way to generate electricity on Earth. But building it on Earth places some significant limits on how much power it can generate, with the darkness and clouds that often get in the way. So there have always been a few people who liked the idea of putting solar panels where they could produce electricity around the clock: space.
While that would get you near-24/7 power production, it comes with a collection of very obvious drawbacks: high launch costs, inability to service the hardware, and the challenge of getting the power back down to where it's needed. How these trade-offs play out in the energy marketplace has been difficult to determine, partly because the energy market is changing so rapidly, and partly because we don't really know what the space-based solar hardware would look like.
Thanks to some funding from a private donor, however, California Institute of Technology researchers have quietly been working on developing the technology needed to get space-based solar to work. And they're apparently ready to subject some test hardware to the rigors of space, thanks to this morning's successful Falcon 9 launch.
(Score: 3, Touché) by BsAtHome on Monday February 13 2023, @11:57AM (5 children)
That would be at about the same time that fusion power will be available, which they say is about 30 years out.
Why not skip the hard tech and directly start to construct a fully closed Dyson sphere?
(Score: 1) by XivLacuna on Monday February 13 2023, @04:22PM (3 children)
A Dyson sphere isn't a practical construction since we'll need to deconstruct a planet or two just for the materials to make one. A Dyson swarm of power collectors is probably the best option.
The problem we'll face is excess heat on Earth if we beam in power from elsewhere.
The solution I like is solar collectors at the Sun-Earth L1 Lagrange point. Block some light and send it to Earth in a more useful form and it won't add additional heat to the planet. Have some ion thrusters on it to keep them in place. Our planet doesn't need the infrared spectrum to hit it at all. If that heat comes from useful machinery instead of infrared light the planet won't have excess energy.
Unfortunately for it to be practical we need to have mining, manufacturing, and a mass driver on the Moon. Which is to say the chances of it happening are low because we're too busy trying to throw money at pointless endeavors instead of something that'll benefit us and our descendants.
(Score: 1, Troll) by Unixnut on Monday February 13 2023, @04:38PM (2 children)
> The problem we'll face is excess heat on Earth if we beam in power from elsewhere.
Yes, as things stand humans cannot alter the climate on earth beyond what the earth would alter anyway, we can only speed up (or slow down) the cycle by some amount.
However the day we start directing energy to earth (either in the form of beaming pure energy down to the surface, or shipping hydrocarbons from other bodies in space to be used on the surface), we will see actual real human induced climate change, and most likely not to the benefit of the existing cycle. The Lagrange idea is an interesting one, because in theory, you are not adding extra energy to the planet, just changing the form it arrives in. Not sure what EM form you could send it in that would not result in the same losses as just collecting it from the surface though.
Another issue with these microwave powered systems is that it doesn't take much for one of these to become a space based weapon. The human race, as both by virtue of nature and nurture, is unable to collectively agree on anything, nor abstain from violence with those they disagree with. As such I don't see any way these systems could be deployed politically, even if we had the tech to do so.
Quite frankly, if we ever get the ability to build such superstructures in space, we may as well just start shipping colonies up there to live off world, and they can make use of the power generated for their sustenance, reducing the load on earth, and avoiding the question of how to get and use the energy on the surface without affecting the climate.
(Score: 3, Insightful) by SomeRandomGeek on Monday February 13 2023, @05:19PM
I'm sensing some confusion as to how the earth's temperature system works. The earth receives a certain amount of solar radiation, which warms it. This solar radiation is absorbed by the matter it hits, then immediately radiated back out into space again. The heat gained to solar radiation and the heat lost due to earth's radiation remain in balance. Except, the wavelength of the radiation is a result of the temperature of the matter radiating it. The hotter the matter, the shorter the wavelength. The opacity/transparency of the atmosphere to specific wavelengths has a huge effect on the system. When the atmosphere is transparent to visible light coming from the sun, but opaque to infrared light radiating from the earth, the planet heats. Visible light from the sun penetrates the atmosphere to warm the surface of the planet, while infrared radiation leaving the planet reflects back off the atmosphere, heating the planet again. The difference between energy in and out causes the temperature of the planet to increase. The increased temperature of the earth causes more energy to be lost as radiation until a new equilibrium point is reached.
Total human energy consumption is about 18 terawatts. Meanwhile, earth receives 174 petawatts of solar radiation, or about 10,000 times as much. Consequently directing a little additional sunlight to the planet for energy use would have a negligible effect on the planet's temperature, while changing the composition of the atmosphere is having huge one.
(Score: 0, Troll) by number11 on Monday February 13 2023, @05:49PM
The power balance stuff can be calculated. I'm not gonna argue about that.
But the "weapon" aspect seems obvious. If it can be used as a weapon (whether directly or as a threat), it will be. Human history guarantees that. Contemplate Y. Prigozhin (the guy who owns Russia's Wagner mercenaries) controlling such a system. Doesn't that give you a nice warm (maybe too warm) feeling? More conventional national leaders might be more subtle (or maybe not), but the same threat will still be there. Trump. Putin. Stalin. Idi Amin. Franco. Hitler. Pinochet. There's lots more.
(Score: 2) by anotherblackhat on Monday February 13 2023, @05:05PM
An earth orbiting SSP is starting construction of a Dyson swarm.
Did you think a Dyson sphere was a solid object?
(Score: 2) by oumuamua on Monday February 13 2023, @05:33PM
As for generating power, here's the meme:
https://www.genolve.com/design/socialmedia/memes/Wind-and-solar-cheaper-than-nuclear-energy [genolve.com]
(Score: 2) by anotherblackhat on Monday February 13 2023, @05:46PM (1 child)
Back when launch costs were $20,000/kg and a 1 kilowatt solar panel weighed a over a ton, it was easy to see that SSP didn't make sense.
Launch costs have dropped to $1,500/kg, and 1 kilowatt solar panels are considerably lighter — and it still doesn't make economic sense.
If we get another order of magnitude combined reduction in mass and launch costs, then maybe.
(Score: 2) by takyon on Tuesday February 14 2023, @06:02AM
Starship payload to LEO has been revised back up [teslarati.com] to 150 tons. My conservative estimate for fully reusable launch cost is $20 million:
Falcon 9: $50 mil / 17,400 kg = $2,873/kg
Starship: $20 mil / 150,000 kg = $133/kg
So there's your 1 order of magnitude. You get a second order of magnitude if the $2 million per launch estimate [techcrunch.com] is ever realized. Big projects in space would have high launch volume that could amortize the costs of the rocket.
I wouldn't be surprised of optimization of Starship's design, width/height, and mass lead to increased payload to orbit, just as Falcon 9 almost doubled over its lifespan.
Very long term, Starship is going to be beaten by some kind of nuclear/fusion thermal rocket.
Costs to LEO are lower than other destinations, like L1 mentioned in another comment, since it could involve additional tanker flights.
Stupidly light, roll-up flexible panels [nasa.gov] can reduce the mass needed. They tend to be less efficient, but they should be easier to deploy.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]