11 ms·

On beaming solar power from low earth orbit

68 points by Jeff_Brown 5y ago

Animats 5y ago
"Many of the raw materials needed for a SSP system can be sourced from asteroids or the lunar surface and if these could be used to manufacture the SSP components in orbit it would cause the cost of the system to plummet. In fact, in-space manufacturing may be key to making SSP a cost-competitive energy resource." This is mostly an excuse to spend money on space programs. It has to be cheaper than ground-based solar power with batteries, which is working and works better every year. It's one of those ideas, like automotive battery swapping, which were a bet against batteries getting better.
- evgen 5y ago
  The interesting thing about space-based solar power is that you do not need to direct the beam at the earth. You can also use it to beam energy to remote probes and robotic installations. If you want to mine asteroids you are better off beaming the energy from earth orbit than you are trying to capture solar on site. Sending the energy from earth makes it much easier to fix/replace the power generation satellite if your remote mission is going to depend on that for power generation.
  - blacksmith_tb 5y ago
    Aiming a tight beam any significant distance would be tough though? I am sure you could hit the moon (not too far) but trying to push a solar sail or the PV on a probe in the outer solar system seems like a very small target (plus there are other bodies in between, sometimes...)
    - evgen 5y ago
      It is not easy, but the energy density of that beam will vastly exceed sunlight at any significant distance. If you are no longer concerned with getting the beamed energy through a wet atmosphere you can also use better frequencies (e.g. visible light lasers or even higher frequencies that might have better margins when it comes to conversion losses.)
      - ben_w 5y ago
        The extra power density of the beam is only useful if you’re capturing a significant fraction of the beam at the far end, which implies both ends have big parabolic mirrors for whatever wavelength you’re using (because that’s the limiting factor in how tight you can focus photons), and if you’re doing that then you could skip the transmitter and point the receiver at the sun to greater effect — you’d need a 100m mirror on the transmitter to hit an Apollo-lander-sized receiver 1.3 light-seconds away — and if you’re concerned about different solar radiation flux at different points, you’re talking about beaming power over multiple light-minutes, main asteroid belt starting about 2 AU from the sun, about 8 light minutes from Earth at minimum. The distance is also large enough you need to be very certain about what’s going on outside your light cone.
xt00 5y ago
Various issues with this tech: 1. "A 2,000 MW SSP system would require a ground receiver covering about 30 square kilometers" 2. The satellite would be in geostationary orbit, or 22,000 miles up, so a directed microwave beam would need to be sent that distance in as tight a beam as possible, so likely the transmitter side on the satellite would be a large dish (to go along with the large surface area of the solar panels, so maybe if the solar panels are solved, then a large dish is ok) 3. Now, if you flew an airplane through that 30 sq km area what happens, or various wildlife like birds fly through that area? Slight cooking? 4. Likely that receiver can't be located near a city because people would be freaked out about being irradiated by a giant microwave beam, so you need transmission towers going across the land to the city you are hoping to power 5. If something goes wrong with your giant power plant in the sky you need to spend serious money to go up and try to fix it. Or, you can dispense with all of that say, ok lets put up a 30 sq km solar array and a battery bank with it and just live with the fact that you don't get sun all of the time. Far cheaper and easier to maintain and upgrade in the future. If this was a discussion about doing this from a space solar farm beaming energy down to mars, then that would be a different story since putting mass into orbit around a planet is cheaper than getting it onto the ground -- so it may actually make some reasonable sense for powering a mars base for some period of time rather than deploying tons of solar panels down on the surface of mars, then on the surface you come up with a low cost way to create some receiver that is low mass and ideally would be just a bunch of wire on a spool that somebody drives back and forth building up over a month or something.
- evgen 5y ago
  The receiving rectenna would be large, but from what I know it would basically consist of a spaced array of small vertical antennas. The sat does not need to be in geostationary orbit and in fact a better solution is to have a constellation at lower orbits. This also eliminates the last problem you posed because if something goes wrong with the sat you just de-orbit it before you had planned and write it off. If you fly through the beam or walk through it you would not know. Do you feel a slight warming when you put your hand on top of your wifi antenna? There are problems with space-based solar and beaming energy, but none of your objections make the list.
ParoxysmalVigor 5y ago
Approach for energy comparison of solar travel and orbital launches: https://en.wikipedia.org/wiki/Delta-v_budget https://en.wikipedia.org/wiki/Delta-v_budget
Geee 5y ago
While Elon Musk is in the position that he could implement this idea, he thinks it's "the stupidest thing ever". [0] [0] https://www.youtube.com/watch?v=9YZVAMh8b0s https://www.youtube.com/watch?v=9YZVAMh8b0s
- worik 5y ago
  Elon Musk and stupid - Peaches and Cream
- danparsonson 5y ago
  Pretty damning considering some of his recent ideas.
- lifekaizen 5y ago
  Excellent link!
the__alchemist 5y ago
No thank you - I've played Sim City. (https://simcity.fandom.com/wiki/Microwave_(disaster) https://simcity.fandom.com/wiki/Microwave_(disaster))
- sircastor 5y ago
  This is what I thought of first as well.
cratermoon 5y ago
Still nope. https://dothemath.ucsd.edu/2012/03/space-based-solar-power/ https://dothemath.ucsd.edu/2012/03/space-based-solar-power/
- elcritch 5y ago
  It’s surprising but even that author turns up a much more reasonable return on investment than I expected. His calculations suggest it’s possible to repay the energy costs, including orbit, after only a few years. Though as he points out there’s lots of elements which are still impractical. Though I wonder if it could be worthwhile given that covering the Sahara with solar panels would change the global climate (particularly Brazil’s) (1). Space based arrays might be a possible way to avoid that. Or perhaps provide a power source for remote areas. A starlink for power would be intriguing. 1: https://www.techtimes.com/articles/257268/20210221/sahara-desert-solar-panels-are-contributing-to-global-warming-scientists-find-out.htm https://www.techtimes.com/articles/257268/20210221/sahara-de...
  - cratermoon 5y ago
    > His calculations suggest it’s possible to repay the energy costs, including orbit, after only a few years. No. No they don't. that's not what his conclusions are at all. How did you even get that? He's comparing space-based vs. land, not space-based vs. nothing. His conclusion is that it's pointless to build solar power collectors in space for terrestrial power applications. In all cases, if you want power on earth, build the solar on earth.
    - elcritch 5y ago
      > Add the embodied energy of the other components in space and on the ground, and I could easily believe we get to a year payback—now bringing the total (manufacture plus launch) to two years and an EROEI around 10:1. > If my 100× light-weighting proves to be unrealistic, and we can only realize a factor of ten improvement over our rooftop panels, the solar panel launch cost climbs to three years, so that adding other components results in perhaps a 4:1 EROEI. > In the end, the EROEI is not as prohibitive as I imagined: it’s not a net energy drain as I might have feared. But it’s not obviously better than conventional solar either. His overall conclusion may reach that conclusion, but his EROI give SPS a net 10:1 to 4:1 energy returns even in his worse case. So regardless if its cost competitive to ground based arrays or not, it might have uses and would likely result in net energy gain vs input (including materials).
giantrobot 5y ago
Space based solar is one of many interesting ideas that only works if you hand wave a lot of extremely hard or intractable problems. Just to construct some massive structure in space is a monumental challenge. Every ton of solar panels or support structure needs some bus to get it to the right orbit and maneuver it in place. Even if you assume fully automated construction you need buses for all the construction robots and tankers to refuel them. Any collisions could scrap the whole project by making a debris cloud in the same orbital plane as the relatively fragile solar panels. That all ignores the sourcing of raw materials, finished components, fuel, and buses to flit everything around. The "easy" answer is "use in-situ materials". In-space mining, refining, and fabrication are all entirely unsolved problems. Even the cheapest vapor ware SpaceX heavy lift rocket isn't cheap enough to build a space based solar plant with components from Earth. The technical difficulty and cost would be ridiculous compared to just building ground based renewables. Ones of billions of dollars will get you gigawatts worth of off-shore wind power or ground based solar. Unless you have access to literal magic there's no situation where space based solar ends up more efficient or cheaper than ground based renewables. The capital expense is literally and figuratively astronomical.
- qayxc 5y ago
  Even if the "cost" of getting the required infrastructure into orbit (assuming Earth-based manufacturing) was close to zero, the energy requirements would still eat up the benefits. SSP only works if every piece of the orbital infrastructure is sourced and built outside of Earth's gravity well. But that's not even the main concern with such system. The primary reason we won't see anything like this anytime soon is the simple fact that such system can easily be weaponised. An SSP is basically a potential space-based weapon. Even if there's no intention to use it as such, some governments are pretty much guaranteed to see it that way and proceed to install actual space-based weaponry in orbit.
  - BurningFrog 5y ago
    > An SSP is basically a potential space-based weapon Asteroid mining has a similar problem. Any tech that can send a metal asteroid to Earth orbit can also smash it into Buenos Aires.
thiagocsf 5y ago
Charlie Stross recently wrote a blog post about this: http://www.antipope.org/charlie/blog-static/2021/09/fossil-fuels-are-dead.html http://www.antipope.org/charlie/blog-static/2021/09/fossil-f... He is a lot more optimistic than the average person in this comments section.
- AndrewDucker 5y ago
  From that post, it gets 4x the efficiency but loses 70% in transmission. Which basically cancel each other out. So the only advantage is the 24x7 availability. Which is a big advantage, but I'm not sure if it's big enough.
  - elcritch 5y ago
    It should be possible with investment in current tech to get transmission losses down to 30-40% or less, IMHO. There’s lot better power transistors, controls, and simulation to improve over the last experiments done decades ago. Some were done in the 1970’s. Incremental improvements do add up.
    - ben_w 5y ago
      You could do antipodal HVDC for ~50% loss with the stuff currently on the market (3.5% loss per 1000km). I do like one of the other suggestions to use this for Mars solar — Mars has a much bigger problem with dust blocking sunlight than Earth does — but I don’t see it being more than experimental here, at least not without a unified world government to remove political risks and a whole bunch of other tech that might make it redundant anyway.
      - elcritch 5y ago
        Mars would be interesting, along with powering space mining operations. Perhaps focused mirrors on the moon or in earth orbit to illuminate earth based solar panel arrays at night. I'd guess aluminum mirrors in space would stay reflective for many decades.
pfdietz 5y ago
Space-based lasers might eventually be a good way to power long distance aircraft.
modeless 5y ago
Elon Musk is in dire need of huge and profitable space-based businesses to justify his big investment in Starship, which is way overkill for any existing space business. And he is incredibly motivated to solve climate issues and big into solar power specifically. And he has repeatedly pursued far-fetched pie-in-the-sky business ideas that are straight out of sci-fi. This business would be perfect for him in about ten different ways, so the fact that he's not doing it means to me that he is completely convinced that it is absolutely impossible to do profitably with current or near-future technology.
- polemic 5y ago
  That's.. a good point. Reminds me of the moonlanding counterfactual: if the USA did not land on the moon, don't you think the Soviet's would've said something about it? Or was the cold-war fabricated as well.
  - generalizations 5y ago
    Apparently, skepticism of the moon landing having happened is much more prevalent in Russia than in the US.
  - cassepipe 5y ago
    I do not think the moonlanding was faked and I really like that argument but still I do wonder what were the real level of intel (and level of confidence they had in that Intel) each of the two world powers had on each other at the time when the USSR existed. Also it could have happened that the USSR decide to propagate that the moon landing was fake for propaganda's purposes.
- beecafe 5y ago
  We need large scale coherent perfect absorbers [0] before we can do long distance power beaming. Other than that with a solar pumped laser (spread out over many m^2 on the ground to reduce the death-ray-ness) you could get decent efficiency. [0] basically a backwards laser. https://en.m.wikipedia.org/wiki/Coherent_perfect_absorber https://en.m.wikipedia.org/wiki/Coherent_perfect_absorber
aaron695 5y ago
> China is investing heavily in SSP and plans to have the first operating SSP plant in orbit by the end of the decade The worlds longest high-voltage subsea cable is only 765 km, the €2 billion Viking Link project SSP is a easy 40,000km, 100km through the atmosphere. So why would the Chinese invest in something so stupid... they are not. What they are looking at is stratospheric power. Balloons at the 10km - 50km mark. It's still possibly to complex, but it's not as childish as space power. Their facility also has the military there. It's a shame people suck, else we could work on real problems like extending power grids over the 765 km mark. A world wide grid would also nullify the bad weather issue. We do it with fibre-optic, and we were doing it in the 90's - https://www.wired.com/1996/12/ffglass/ https://www.wired.com/1996/12/ffglass/ (Neal Stephenson) A bit of a tech talk on what China is doing here with SSP - https://spacewatch.global/2021/07/spacewatchgl-column-dongfang-hour-china-aerospace-news-roundup-19-25-july-2021/ https://spacewatch.global/2021/07/spacewatchgl-column-dongfa...
dd444fgdfg 5y ago
and eventually end up with a Dyson Sphere around earth. Doesn't sound like a great idea to redirect earth bound heat for electricity
- blacksmith_tb 5y ago
  That sounds like a selling point to me - obviously geoengineering is controversial, but if you could overcome that resistance, you could slow warming and also generate power, win-win.
darksaints 5y ago
Maybe if we ever find a way to manufacture continuous strands of nanotubes, we could create both space elevators as well as wired LEO solar power.
fanick 5y ago
I remember reading about this solar power beam concept when I was a kid in one children magazine. The article mentioned Peter Glaser as the author of the idea and it had these gorgeous illustrations. After some digging I managed to find it in the depths of the internet https://imgur.com/a/1MPWd62 https://imgur.com/a/1MPWd62 https://imgur.com/a/sF3MzSj https://imgur.com/a/sF3MzSj
cassepipe 5y ago
How is the electrical power transmitted to earth? Radio wawes? Couldn't that produce interferences?
ZeroGravitas 5y ago
I don't like this particular writeup, the use of 'baseload' makes me think this is someone who doesn't understand energy markets trying to use it as an excuse for funding rockets. But I do wonder if there might be better applications if you think outside the box. Can standard PV installations be the receiver? Could this act as a complement to ground based arrays by using them at night or during winter by supplementing natural light? How does the math look for wavelengths that PV can capture? The ability to inject extra power into the grid as required might make a small number of these cost effective for the whole planet, rather than as a bulk energy source. Is there any way of extracting CO2 from the atmosphere or breaking down methane faster that could be done from low earth orbit with cheap enough energy? Could these supplement the energy requirements of planes, boats or trains by beaming energy at moving targets? (Feels like the receiver would need to be too large for this to work well). Is there any use for heating clouds? Can this cause rain to control weather? As well as the standard weather control thing, that could also help with terrestrial solar production.
- londons_explore 5y ago
  > Can standard PV installations be the receiver? space based mirrors could be really cheap and light. Think of a big mylar sheet held flat with this[1] mechanism. When you double the brightness of light on a solar panel, you more than double the power output, so using a series of space based mirrors could really increase the return-on-investment of on-ground solar panels. Probably not very wildlife friendly... Perhaps best to do it in a desert. [1]: https://www.youtube.com/watch?v=9iTLkKfip4o https://www.youtube.com/watch?v=9iTLkKfip4o
citizenpaul 5y ago
This will never happen. Period.
ThePadawan 5y ago
Tongue-in-cheek question: If it's in geostationary orbit, couldn't we just run a cable down (/up)?
daveac 5y ago
What is the effect of pumping more energy into the environment? Would that just mean global warming via a different method?

68 points by Jeff_Brown 5y ago

"Many of the raw materials needed for a SSP system can be sourced from asteroids or the lunar surface and if these could be used to manufacture the SSP components in orbit it would cause the cost of the system to plummet. In fact, in-space manufacturing may be key to making SSP a cost-competitive energy resource." This is mostly an excuse to spend money on space programs. It has to be cheaper than ground-based solar power with batteries, which is working and works better every year. It's one of those ideas, like automotive battery swapping, which were a bet against batteries getting better.

evgen 5y ago
The interesting thing about space-based solar power is that you do not need to direct the beam at the earth. You can also use it to beam energy to remote probes and robotic installations. If you want to mine asteroids you are better off beaming the energy from earth orbit than you are trying to capture solar on site. Sending the energy from earth makes it much easier to fix/replace the power generation satellite if your remote mission is going to depend on that for power generation.
- blacksmith_tb 5y ago
  Aiming a tight beam any significant distance would be tough though? I am sure you could hit the moon (not too far) but trying to push a solar sail or the PV on a probe in the outer solar system seems like a very small target (plus there are other bodies in between, sometimes...)
  - evgen 5y ago
    It is not easy, but the energy density of that beam will vastly exceed sunlight at any significant distance. If you are no longer concerned with getting the beamed energy through a wet atmosphere you can also use better frequencies (e.g. visible light lasers or even higher frequencies that might have better margins when it comes to conversion losses.)
    - ben_w 5y ago
      The extra power density of the beam is only useful if you’re capturing a significant fraction of the beam at the far end, which implies both ends have big parabolic mirrors for whatever wavelength you’re using (because that’s the limiting factor in how tight you can focus photons), and if you’re doing that then you could skip the transmitter and point the receiver at the sun to greater effect — you’d need a 100m mirror on the transmitter to hit an Apollo-lander-sized receiver 1.3 light-seconds away — and if you’re concerned about different solar radiation flux at different points, you’re talking about beaming power over multiple light-minutes, main asteroid belt starting about 2 AU from the sun, about 8 light minutes from Earth at minimum. The distance is also large enough you need to be very certain about what’s going on outside your light cone.

xt00 5y ago

Various issues with this tech: 1. "A 2,000 MW SSP system would require a ground receiver covering about 30 square kilometers" 2. The satellite would be in geostationary orbit, or 22,000 miles up, so a directed microwave beam would need to be sent that distance in as tight a beam as possible, so likely the transmitter side on the satellite would be a large dish (to go along with the large surface area of the solar panels, so maybe if the solar panels are solved, then a large dish is ok) 3. Now, if you flew an airplane through that 30 sq km area what happens, or various wildlife like birds fly through that area? Slight cooking? 4. Likely that receiver can't be located near a city because people would be freaked out about being irradiated by a giant microwave beam, so you need transmission towers going across the land to the city you are hoping to power 5. If something goes wrong with your giant power plant in the sky you need to spend serious money to go up and try to fix it. Or, you can dispense with all of that say, ok lets put up a 30 sq km solar array and a battery bank with it and just live with the fact that you don't get sun all of the time. Far cheaper and easier to maintain and upgrade in the future. If this was a discussion about doing this from a space solar farm beaming energy down to mars, then that would be a different story since putting mass into orbit around a planet is cheaper than getting it onto the ground -- so it may actually make some reasonable sense for powering a mars base for some period of time rather than deploying tons of solar panels down on the surface of mars, then on the surface you come up with a low cost way to create some receiver that is low mass and ideally would be just a bunch of wire on a spool that somebody drives back and forth building up over a month or something.

evgen 5y ago
The receiving rectenna would be large, but from what I know it would basically consist of a spaced array of small vertical antennas. The sat does not need to be in geostationary orbit and in fact a better solution is to have a constellation at lower orbits. This also eliminates the last problem you posed because if something goes wrong with the sat you just de-orbit it before you had planned and write it off. If you fly through the beam or walk through it you would not know. Do you feel a slight warming when you put your hand on top of your wifi antenna? There are problems with space-based solar and beaming energy, but none of your objections make the list.

ParoxysmalVigor 5y ago

Approach for energy comparison of solar travel and orbital launches: https://en.wikipedia.org/wiki/Delta-v_budget https://en.wikipedia.org/wiki/Delta-v_budget

Geee 5y ago

While Elon Musk is in the position that he could implement this idea, he thinks it's "the stupidest thing ever". [0] [0] https://www.youtube.com/watch?v=9YZVAMh8b0s https://www.youtube.com/watch?v=9YZVAMh8b0s

worik 5y ago
Elon Musk and stupid - Peaches and Cream
danparsonson 5y ago
Pretty damning considering some of his recent ideas.
lifekaizen 5y ago
Excellent link!

the__alchemist 5y ago

No thank you - I've played Sim City. (https://simcity.fandom.com/wiki/Microwave_(disaster) https://simcity.fandom.com/wiki/Microwave_(disaster))

sircastor 5y ago
This is what I thought of first as well.

cratermoon 5y ago

Still nope. https://dothemath.ucsd.edu/2012/03/space-based-solar-power/ https://dothemath.ucsd.edu/2012/03/space-based-solar-power/

elcritch 5y ago
It’s surprising but even that author turns up a much more reasonable return on investment than I expected. His calculations suggest it’s possible to repay the energy costs, including orbit, after only a few years. Though as he points out there’s lots of elements which are still impractical. Though I wonder if it could be worthwhile given that covering the Sahara with solar panels would change the global climate (particularly Brazil’s) (1). Space based arrays might be a possible way to avoid that. Or perhaps provide a power source for remote areas. A starlink for power would be intriguing. 1: https://www.techtimes.com/articles/257268/20210221/sahara-desert-solar-panels-are-contributing-to-global-warming-scientists-find-out.htm https://www.techtimes.com/articles/257268/20210221/sahara-de...
- cratermoon 5y ago
  > His calculations suggest it’s possible to repay the energy costs, including orbit, after only a few years. No. No they don't. that's not what his conclusions are at all. How did you even get that? He's comparing space-based vs. land, not space-based vs. nothing. His conclusion is that it's pointless to build solar power collectors in space for terrestrial power applications. In all cases, if you want power on earth, build the solar on earth.
  - elcritch 5y ago
    > Add the embodied energy of the other components in space and on the ground, and I could easily believe we get to a year payback—now bringing the total (manufacture plus launch) to two years and an EROEI around 10:1. > If my 100× light-weighting proves to be unrealistic, and we can only realize a factor of ten improvement over our rooftop panels, the solar panel launch cost climbs to three years, so that adding other components results in perhaps a 4:1 EROEI. > In the end, the EROEI is not as prohibitive as I imagined: it’s not a net energy drain as I might have feared. But it’s not obviously better than conventional solar either. His overall conclusion may reach that conclusion, but his EROI give SPS a net 10:1 to 4:1 energy returns even in his worse case. So regardless if its cost competitive to ground based arrays or not, it might have uses and would likely result in net energy gain vs input (including materials).

giantrobot 5y ago

Space based solar is one of many interesting ideas that only works if you hand wave a lot of extremely hard or intractable problems. Just to construct some massive structure in space is a monumental challenge. Every ton of solar panels or support structure needs some bus to get it to the right orbit and maneuver it in place. Even if you assume fully automated construction you need buses for all the construction robots and tankers to refuel them. Any collisions could scrap the whole project by making a debris cloud in the same orbital plane as the relatively fragile solar panels. That all ignores the sourcing of raw materials, finished components, fuel, and buses to flit everything around. The "easy" answer is "use in-situ materials". In-space mining, refining, and fabrication are all entirely unsolved problems. Even the cheapest vapor ware SpaceX heavy lift rocket isn't cheap enough to build a space based solar plant with components from Earth. The technical difficulty and cost would be ridiculous compared to just building ground based renewables. Ones of billions of dollars will get you gigawatts worth of off-shore wind power or ground based solar. Unless you have access to literal magic there's no situation where space based solar ends up more efficient or cheaper than ground based renewables. The capital expense is literally and figuratively astronomical.

qayxc 5y ago
Even if the "cost" of getting the required infrastructure into orbit (assuming Earth-based manufacturing) was close to zero, the energy requirements would still eat up the benefits. SSP only works if every piece of the orbital infrastructure is sourced and built outside of Earth's gravity well. But that's not even the main concern with such system. The primary reason we won't see anything like this anytime soon is the simple fact that such system can easily be weaponised. An SSP is basically a potential space-based weapon. Even if there's no intention to use it as such, some governments are pretty much guaranteed to see it that way and proceed to install actual space-based weaponry in orbit.
- BurningFrog 5y ago
  > An SSP is basically a potential space-based weapon Asteroid mining has a similar problem. Any tech that can send a metal asteroid to Earth orbit can also smash it into Buenos Aires.

thiagocsf 5y ago

Charlie Stross recently wrote a blog post about this: http://www.antipope.org/charlie/blog-static/2021/09/fossil-fuels-are-dead.html http://www.antipope.org/charlie/blog-static/2021/09/fossil-f... He is a lot more optimistic than the average person in this comments section.

AndrewDucker 5y ago
From that post, it gets 4x the efficiency but loses 70% in transmission. Which basically cancel each other out. So the only advantage is the 24x7 availability. Which is a big advantage, but I'm not sure if it's big enough.
- elcritch 5y ago
  It should be possible with investment in current tech to get transmission losses down to 30-40% or less, IMHO. There’s lot better power transistors, controls, and simulation to improve over the last experiments done decades ago. Some were done in the 1970’s. Incremental improvements do add up.
  - ben_w 5y ago
    You could do antipodal HVDC for ~50% loss with the stuff currently on the market (3.5% loss per 1000km). I do like one of the other suggestions to use this for Mars solar — Mars has a much bigger problem with dust blocking sunlight than Earth does — but I don’t see it being more than experimental here, at least not without a unified world government to remove political risks and a whole bunch of other tech that might make it redundant anyway.
    - elcritch 5y ago
      Mars would be interesting, along with powering space mining operations. Perhaps focused mirrors on the moon or in earth orbit to illuminate earth based solar panel arrays at night. I'd guess aluminum mirrors in space would stay reflective for many decades.

pfdietz 5y ago

Space-based lasers might eventually be a good way to power long distance aircraft.

modeless 5y ago

Elon Musk is in dire need of huge and profitable space-based businesses to justify his big investment in Starship, which is way overkill for any existing space business. And he is incredibly motivated to solve climate issues and big into solar power specifically. And he has repeatedly pursued far-fetched pie-in-the-sky business ideas that are straight out of sci-fi. This business would be perfect for him in about ten different ways, so the fact that he's not doing it means to me that he is completely convinced that it is absolutely impossible to do profitably with current or near-future technology.

polemic 5y ago
That's.. a good point. Reminds me of the moonlanding counterfactual: if the USA did not land on the moon, don't you think the Soviet's would've said something about it? Or was the cold-war fabricated as well.
- generalizations 5y ago
  Apparently, skepticism of the moon landing having happened is much more prevalent in Russia than in the US.
- cassepipe 5y ago
  I do not think the moonlanding was faked and I really like that argument but still I do wonder what were the real level of intel (and level of confidence they had in that Intel) each of the two world powers had on each other at the time when the USSR existed. Also it could have happened that the USSR decide to propagate that the moon landing was fake for propaganda's purposes.
beecafe 5y ago
We need large scale coherent perfect absorbers [0] before we can do long distance power beaming. Other than that with a solar pumped laser (spread out over many m^2 on the ground to reduce the death-ray-ness) you could get decent efficiency. [0] basically a backwards laser. https://en.m.wikipedia.org/wiki/Coherent_perfect_absorber https://en.m.wikipedia.org/wiki/Coherent_perfect_absorber

aaron695 5y ago

> China is investing heavily in SSP and plans to have the first operating SSP plant in orbit by the end of the decade The worlds longest high-voltage subsea cable is only 765 km, the €2 billion Viking Link project SSP is a easy 40,000km, 100km through the atmosphere. So why would the Chinese invest in something so stupid... they are not. What they are looking at is stratospheric power. Balloons at the 10km - 50km mark. It's still possibly to complex, but it's not as childish as space power. Their facility also has the military there. It's a shame people suck, else we could work on real problems like extending power grids over the 765 km mark. A world wide grid would also nullify the bad weather issue. We do it with fibre-optic, and we were doing it in the 90's - https://www.wired.com/1996/12/ffglass/ https://www.wired.com/1996/12/ffglass/ (Neal Stephenson) A bit of a tech talk on what China is doing here with SSP - https://spacewatch.global/2021/07/spacewatchgl-column-dongfang-hour-china-aerospace-news-roundup-19-25-july-2021/ https://spacewatch.global/2021/07/spacewatchgl-column-dongfa...

dd444fgdfg 5y ago

and eventually end up with a Dyson Sphere around earth. Doesn't sound like a great idea to redirect earth bound heat for electricity

blacksmith_tb 5y ago
That sounds like a selling point to me - obviously geoengineering is controversial, but if you could overcome that resistance, you could slow warming and also generate power, win-win.

darksaints 5y ago

Maybe if we ever find a way to manufacture continuous strands of nanotubes, we could create both space elevators as well as wired LEO solar power.

fanick 5y ago

I remember reading about this solar power beam concept when I was a kid in one children magazine. The article mentioned Peter Glaser as the author of the idea and it had these gorgeous illustrations. After some digging I managed to find it in the depths of the internet https://imgur.com/a/1MPWd62 https://imgur.com/a/1MPWd62 https://imgur.com/a/sF3MzSj https://imgur.com/a/sF3MzSj

cassepipe 5y ago

How is the electrical power transmitted to earth? Radio wawes? Couldn't that produce interferences?

ZeroGravitas 5y ago

I don't like this particular writeup, the use of 'baseload' makes me think this is someone who doesn't understand energy markets trying to use it as an excuse for funding rockets. But I do wonder if there might be better applications if you think outside the box. Can standard PV installations be the receiver? Could this act as a complement to ground based arrays by using them at night or during winter by supplementing natural light? How does the math look for wavelengths that PV can capture? The ability to inject extra power into the grid as required might make a small number of these cost effective for the whole planet, rather than as a bulk energy source. Is there any way of extracting CO2 from the atmosphere or breaking down methane faster that could be done from low earth orbit with cheap enough energy? Could these supplement the energy requirements of planes, boats or trains by beaming energy at moving targets? (Feels like the receiver would need to be too large for this to work well). Is there any use for heating clouds? Can this cause rain to control weather? As well as the standard weather control thing, that could also help with terrestrial solar production.

londons_explore 5y ago
> Can standard PV installations be the receiver? space based mirrors could be really cheap and light. Think of a big mylar sheet held flat with this[1] mechanism. When you double the brightness of light on a solar panel, you more than double the power output, so using a series of space based mirrors could really increase the return-on-investment of on-ground solar panels. Probably not very wildlife friendly... Perhaps best to do it in a desert. [1]: https://www.youtube.com/watch?v=9iTLkKfip4o https://www.youtube.com/watch?v=9iTLkKfip4o

citizenpaul 5y ago

This will never happen. Period.

ThePadawan 5y ago

Tongue-in-cheek question: If it's in geostationary orbit, couldn't we just run a cable down (/up)?

daveac 5y ago

What is the effect of pumping more energy into the environment? Would that just mean global warming via a different method?