Solar power from space? it might happen in a couple of years(arstechnica.com)
arstechnica.com
Solar power from space? it might happen in a couple of years
https://arstechnica.com/space/2024/10/solar-power-from-space-actually-it-might-happen-in-a-couple-of-years/
61 comments
Found a rather... skeptical take (I'd argue it's more of a takedown)[0]. A bit crazy how far off the math is from viability, for a company that someone actually invested money in. Impressive salesmanship though.
[0] https://www.youtube.com/watch?v=lkjyeI0ykGM
[0] https://www.youtube.com/watch?v=lkjyeI0ykGM
Yeah that looks pretty bad. I'm trying to figure out if something got lost in translation or if Reflect Orbital is just running an outright scam. It's pretty clear a 10m X 10m square can't transmit 200W/sqm to a 3km area. So either those figures were for a different version of the product (like maybe an array of hundreds or thousands of these cubesats all working in concert?) or he's just flat out lying about some very important figures.
So in case anyone cares, I re-watched the podcast and I'm leaning towards something getting lost in translation (or, more uncharitably, Ben being misleading about what he was describing in order to make the company look better than it is).
At 47:42 he says:
> So serving energy customers is kind of like the end state, you know, that, that makes sense when you're launching like, you know, full Falcon Heavies full of full of vehicles.
Implying he knows you're not getting 200W/m^2 with only a single 10m x 10m 16u cubesat. He says for single satellites their short term goal is to be an alternative for street lights in undeveloped areas, which requires much less power per unit area.
And at 1:11:57:
> And you can also optimize like different curves of customer saturation, you know, so like initially, you're not going to have as many customers excited to buy, you know, a couple minutes of sunlight that's not very bright. But later down the line you're going to have a lot of people who are very interested in buying a lot of sunlight. Um, you know, at the kind of point where we're, you know, a couple hundred Watts per square meter for, for quite a while.
So it sounds like 200W/m^2 is a long term goal, not something they're planning to have right away with the 100m^2 satellites.
Would be interesting to run the numbers and find out exactly what would be needed for 200W/m^2 in the maximally bright part of the illuminated area, in terms of the size and number of satellites required.
At 47:42 he says:
> So serving energy customers is kind of like the end state, you know, that, that makes sense when you're launching like, you know, full Falcon Heavies full of full of vehicles.
Implying he knows you're not getting 200W/m^2 with only a single 10m x 10m 16u cubesat. He says for single satellites their short term goal is to be an alternative for street lights in undeveloped areas, which requires much less power per unit area.
And at 1:11:57:
> And you can also optimize like different curves of customer saturation, you know, so like initially, you're not going to have as many customers excited to buy, you know, a couple minutes of sunlight that's not very bright. But later down the line you're going to have a lot of people who are very interested in buying a lot of sunlight. Um, you know, at the kind of point where we're, you know, a couple hundred Watts per square meter for, for quite a while.
So it sounds like 200W/m^2 is a long term goal, not something they're planning to have right away with the 100m^2 satellites.
Would be interesting to run the numbers and find out exactly what would be needed for 200W/m^2 in the maximally bright part of the illuminated area, in terms of the size and number of satellites required.
It would be huge to actually get a real no bullshit answer from people like him.
Either he got some strategy which is smart but he can't communicate, or he tries playing a very long game, or he actually doesn't understand it and is just a normal person and normal people need experts telling them why it sounds good but is stupid or he has some VC experts telling him how to communicate to get money without a real endgoal but pivoting to something else later.
Either he got some strategy which is smart but he can't communicate, or he tries playing a very long game, or he actually doesn't understand it and is just a normal person and normal people need experts telling them why it sounds good but is stupid or he has some VC experts telling him how to communicate to get money without a real endgoal but pivoting to something else later.
I avoid "debunk" channel like theses.
Lots of them "debunked" SpaceX at it's beginning.
> I listened to a podcast[1] a few months ago which proposed the (IMHO) more innovative idea of using giant, ultra-light foil mirrors in space to sell sunlight to existing solar farms at night.
What would that look like from Earth? I can't imagine star-gazing with a giant mirror shining down on me.
What would that look like from Earth? I can't imagine star-gazing with a giant mirror shining down on me.
I think the idea is it would look a bit like daylight, but only if you're in the area being lit (e.g. standing next to the solar farm), otherwise you wouldn't see it at all. But in practice, I'm not sure. I could imagine light leakage being an issue.
You write large orbital mirror for redirecting sunlight to solar farms I read space-based magnifying glass to cook any spot on the ground. Without running the numbers I'm not sure my intuition holds, does it?
haha light on details
I'll keep saying this until I'm blue in the face: solar power is the future. It is the only form of power generation that directly genreates power rather than turning a turbine. As such it has no moving parts (apart from, maybe, an array that gets tilted to face the Sun for higher efficiency but that's optional) and has no emissions.
The cost of solar power has plummetted in the last 2 decades and nobody is quite sure where this will bottom out.
Now obviously sometimes it's night time and sometimes it's just cloudy. You have a number of options for this, in increasing level of engineering and technological difficulty:
1. Do nothing. Just take power when it is available. This works surprisingly well for a lot of our power usage. Power usage peaks in daylight hours so solar reduces your baseload requirements. Sometimes you can simply do things when the weather doesn't permit (eg data centers).
2. Store excess power in another form. This could be batteries but it could also be things like sequestering carbon from the air into a hydrocarbon form you can later burn for power. This is carbon neutral by definition. This method currently isn't economic. In some cases that doesn't matter (eg in cold climates where current batteries aren't particularly effective).
3. Power satellites that bean down power. A solar collector in space would produce ~7 times as much power as a terrestrial collector because there's no day/night or weather interruptions nor atmospheric loss. It is technically feasible to beam down power.
4. Build an orbital ring. Attach solar collectors to it. Run cables to the ground. Obviously this is more far future.
More [1].
[1]: https://www.youtube.com/watch?v=eBCbdThIJNE
The cost of solar power has plummetted in the last 2 decades and nobody is quite sure where this will bottom out.
Now obviously sometimes it's night time and sometimes it's just cloudy. You have a number of options for this, in increasing level of engineering and technological difficulty:
1. Do nothing. Just take power when it is available. This works surprisingly well for a lot of our power usage. Power usage peaks in daylight hours so solar reduces your baseload requirements. Sometimes you can simply do things when the weather doesn't permit (eg data centers).
2. Store excess power in another form. This could be batteries but it could also be things like sequestering carbon from the air into a hydrocarbon form you can later burn for power. This is carbon neutral by definition. This method currently isn't economic. In some cases that doesn't matter (eg in cold climates where current batteries aren't particularly effective).
3. Power satellites that bean down power. A solar collector in space would produce ~7 times as much power as a terrestrial collector because there's no day/night or weather interruptions nor atmospheric loss. It is technically feasible to beam down power.
4. Build an orbital ring. Attach solar collectors to it. Run cables to the ground. Obviously this is more far future.
More [1].
[1]: https://www.youtube.com/watch?v=eBCbdThIJNE
Won't your #2 be economic when photovoltaic power is basically free ? The day is coming.
> it might happen in a couple of years
Narrator: It will not happen.
The only place space based solar makes sense is on things that are in space.
Narrator: It will not happen.
The only place space based solar makes sense is on things that are in space.
I think there probably is an actual niche for space-based solar, depending on how retarget-able it is. Imagine being able to beam 24/7 power to remote mining or military installations, or if you could really steer it, beaming it the receiving station with the highest power prices. If it's competing with diesel that needs to be flown in (or trucked through hazardous terrain), it would be much easier for it to be competitive.
So you would build a solar array in space at enormous cost and then need to truck or fly in a receiver, and build it. Versus trucking and building a solar plant with batteries on site. I still don’t think that it’s ever going to make sense.
Have you seen an EIS (Environmental Impact Statement) for a new mine in pristine wilderness? They take tens of millions of dollars and the better part of a decade. Mining companies would throw money at you if you could turn "ship in and burn a bunch of diesel on-site" or "clear 200 acres of wilderness for solar panels" into "build a small collector on-site one time" in their EIS. That being said, there aren't that many new mine sites going up in the world.
I suspect we could get collectors pretty small and efficient if they were optimized.
I suspect we could get collectors pretty small and efficient if they were optimized.
I'm skeptical. How much of that EIS cost is the generators? Diesel is well understood, reliable, and in the grand scheme of thing shipping it in isn't that big of a hassle.
Obviously if you are mining something you already need to have shipping concerned worked out. You aren't flying ore out by helicopter. Getting Diesel delivered for your generators will be more expensive than your local gas station, but it's hard to imagine a space solar solution ever being competitive given that you need to build a constellation of the things, launch them into space, and then maintain the array and the ground stations. You also have to convince the mining company that not only will your brand new technology be reliable, but that your business model is sound enough that you won't be out of business a couple of years into their mining operation.
The idea that the company will be doing revenue service in 2 years is complete hogwash. This reeks of investor scam. They would have to be launching prototypes 5 years ago for this to even be in the realm of reason.
Finally: How in the world is the EIS going to be any easier for "we intend to hit one spot on Earth with intense microwave radiation for years on end"? I feel like that is going to raise a lot of flags over at the environmental regulator's office.
Obviously if you are mining something you already need to have shipping concerned worked out. You aren't flying ore out by helicopter. Getting Diesel delivered for your generators will be more expensive than your local gas station, but it's hard to imagine a space solar solution ever being competitive given that you need to build a constellation of the things, launch them into space, and then maintain the array and the ground stations. You also have to convince the mining company that not only will your brand new technology be reliable, but that your business model is sound enough that you won't be out of business a couple of years into their mining operation.
The idea that the company will be doing revenue service in 2 years is complete hogwash. This reeks of investor scam. They would have to be launching prototypes 5 years ago for this to even be in the realm of reason.
Finally: How in the world is the EIS going to be any easier for "we intend to hit one spot on Earth with intense microwave radiation for years on end"? I feel like that is going to raise a lot of flags over at the environmental regulator's office.
> it's hard to imagine a space solar solution ever being competitive given that you need to build a constellation of the things, launch them into space
Someone has to do that, once. Yes, that company will need to sell their offering to many different clients over a long time to recoup those costs. One single mining site is not covering the cost of the initial space deployment, obviously.
> The idea that the company will be doing revenue service in 2 years is complete hogwash. This reeks of investor scam.
Well I certainly agree with that. I'm not defending this particular company.
> How in the world is the EIS going to be any easier for "we intend to hit one spot on Earth with intense microwave radiation for years on end"?
Compared with "we're going to do a billion small explosions of fossil fuels and emit the combustion byproducts into the air for years on end?" All you've done is write a scary-sounding description. Plenty of things that sound scary end up being safe in the end. It doesn't take much imagination to see a possibility that this technology could easily be the best option for delivering power to a highly protected area. Literally any technology sounds ridiculous if you describe it like that.
"You wish to sail a ship up stream by lighting a fire under its decks, I have no time for such nonsense." - Napoleon Bonaparte on the use of ironclads
Someone has to do that, once. Yes, that company will need to sell their offering to many different clients over a long time to recoup those costs. One single mining site is not covering the cost of the initial space deployment, obviously.
> The idea that the company will be doing revenue service in 2 years is complete hogwash. This reeks of investor scam.
Well I certainly agree with that. I'm not defending this particular company.
> How in the world is the EIS going to be any easier for "we intend to hit one spot on Earth with intense microwave radiation for years on end"?
Compared with "we're going to do a billion small explosions of fossil fuels and emit the combustion byproducts into the air for years on end?" All you've done is write a scary-sounding description. Plenty of things that sound scary end up being safe in the end. It doesn't take much imagination to see a possibility that this technology could easily be the best option for delivering power to a highly protected area. Literally any technology sounds ridiculous if you describe it like that.
"You wish to sail a ship up stream by lighting a fire under its decks, I have no time for such nonsense." - Napoleon Bonaparte on the use of ironclads
Good counter points, thanks for sharing those.
would be a pretty cool weapon, you could melt the Kremlin and blow up every missile that make it past launch.
Agreed. It would be a great option for ground stations on the moon. Lunar nights are 14 days long.
Surprised no one has mentioned the classic Sim City 2000 microwave power plants that tended to erupt into flames. [1]
[1] https://simcity.fandom.com/wiki/Microwave_Power_Plant
[1] https://simcity.fandom.com/wiki/Microwave_Power_Plant
A mobile receiving station? Uh? That sounds really bad, right?
Don't hold your breath on this one. I expect it to take a lot longer, but not for technical reasons. The truth is that however you do this you are developing weapons. At best, your allies will be on your side but your enemies will play this up, discussing how versions of whatever you do can be used against them. And even if exaggerated (and boy will it be), there will be grains of truth. These are the hardest lies to fight because they're half lies.
The problem always lies in how you get that energy down to Earth. There's no way to do this that can't also be used in a way that can be destructive. Even this proposal at 1kW you can do some damage. They're doing IR because this is fairly transmissible through the atmosphere but it can still be damaging. These range from a directed energy weapon (likely aimed at electronics) to a more denial of service attack (you'd need higher energy than 1kW). There's another proposal about just redirecting light[0] and I think it is easier to imagine how this is a weapon. Could you imagine someone just making you, in your house (or worse, it follows you around), always live in daylight? It would drive you crazy. I know the Nords, Alaskans, Canadians, and others will tell you there's challenges to living in perpetual daylight. But you can destabilize crops, which need night, insects and wildlife, and I'll let your imagination run wild. But this is also true for IR light, you just won't see it with your eyes. That still affects many insects, snakes, fish, and other animals, not to mention plants. IR is heat, and it doesn't take much heat to disrupt things.
On a different point:
[0] https://x.com/colecallinan/status/1826683972207661499
[1] https://www.forbes.com/profile/baiju-bhatt/
The problem always lies in how you get that energy down to Earth. There's no way to do this that can't also be used in a way that can be destructive. Even this proposal at 1kW you can do some damage. They're doing IR because this is fairly transmissible through the atmosphere but it can still be damaging. These range from a directed energy weapon (likely aimed at electronics) to a more denial of service attack (you'd need higher energy than 1kW). There's another proposal about just redirecting light[0] and I think it is easier to imagine how this is a weapon. Could you imagine someone just making you, in your house (or worse, it follows you around), always live in daylight? It would drive you crazy. I know the Nords, Alaskans, Canadians, and others will tell you there's challenges to living in perpetual daylight. But you can destabilize crops, which need night, insects and wildlife, and I'll let your imagination run wild. But this is also true for IR light, you just won't see it with your eyes. That still affects many insects, snakes, fish, and other animals, not to mention plants. IR is heat, and it doesn't take much heat to disrupt things.
On a different point:
> told me he wants to reinvent the idea of space-based solar power beginning with a relatively small investment—likely a bit north of $10 million
> That physicist is Baiju Bhatt, who co-founded the electronic trading platform Robinhood in 2013
[0] https://x.com/colecallinan/status/1826683972207661499
[1] https://www.forbes.com/profile/baiju-bhatt/
200 w/sqm is not a weapon. It's barely enough to keep you warm in the winter time.
You're not wrong, but that doesn't mean you understood my point.
It seems you aren't aware that space is not controlled by a single country. It's ruled by international agreements. Do you really think everyone sitting at that table is going to be using that power to make laws based purely on the merit of the technology and it's safety? Or do you think they're going to be bullshit arguments that are reaching at best? We both know the answer to that. Predicting what they will argue is not the same thing as saying their points will be valid. But you also can't just pretend that bullshit won't exist.
It seems you aren't aware that space is not controlled by a single country. It's ruled by international agreements. Do you really think everyone sitting at that table is going to be using that power to make laws based purely on the merit of the technology and it's safety? Or do you think they're going to be bullshit arguments that are reaching at best? We both know the answer to that. Predicting what they will argue is not the same thing as saying their points will be valid. But you also can't just pretend that bullshit won't exist.
The laws of physics make Jewish space lasers impossible.
Anybody willing to ignore international agreements to develop weapons can reach for the very effective nuclear, chemical or biological weapons rather than for imaginary impossible ones.
Using a directed energy weapon to shoot down drones is millions of times more feasible than space lasers -- thousands of times more concentrated power, thousands of times less air dispersion, on the softest possible target. Yet using lasers to shoot down drones is so ineffective that we're not doing it. You're proposing something a billion times more difficult.
Anybody willing to ignore international agreements to develop weapons can reach for the very effective nuclear, chemical or biological weapons rather than for imaginary impossible ones.
Using a directed energy weapon to shoot down drones is millions of times more feasible than space lasers -- thousands of times more concentrated power, thousands of times less air dispersion, on the softest possible target. Yet using lasers to shoot down drones is so ineffective that we're not doing it. You're proposing something a billion times more difficult.
> Anybody willing to ignore international agreements to develop weapons can reach for the very effective nuclear, chemical or biological weapons rather than for imaginary impossible ones.
> Yet using lasers to shoot down drones is so ineffective that we're not doing it. You're proposing something a billion times more difficult.
Doesn't ALL solar power come from space?
This had better not heat the atmosphere...
These satellites also shade the Earth.
In Geostationary orbit? Only for something like 3% of the time. The rest of the time they're off to the side. They'd mostly be catching light that would otherwise never hit Earth.
That's not a bug, that's a feature.
Did we learn nothing from Sim City?
Thats just not realistic at all. Its so far away from realistic, i'm not sure why arstechnica is posting this VC ad.
You need the size of the area you want to shine it up which is HUGE.
Why do we entertain this? How do people get funding for doing this? Are people so ignorant?
You need the size of the area you want to shine it up which is HUGE.
Why do we entertain this? How do people get funding for doing this? Are people so ignorant?
10 years ago, having a reusable rocket booster was not realistic.
5 years ago, catching a rocket booster with a tower was not realistic.
The past 150 years has been wild, I'm not too sure I think anything is unrealistic anymore.
5 years ago, catching a rocket booster with a tower was not realistic.
The past 150 years has been wild, I'm not too sure I think anything is unrealistic anymore.
How about we plaster our existing area full of PV and than in 10 years we talk about space?
Plenty of reasons to want this to work. Ground-based solar has so many flaws - ecological, legal, social, even efficiency is poor. And we aren't making any more open ground near cities to put square miles of solar farms.
Space-based is becoming more attractive every year. Lift costs, panel weight and cost, computing power are all going in the right direction to improve the space-solar economic equation. As for space, a few square miles is trivial to find a place for.
Further, the usual bugaboos about "How do you get it down here?!" (microwaves to high-capacity receivers) can be circumvented entirely if you use the power in space e.g. in AI-training compute centers also in orbit.
Space-based is becoming more attractive every year. Lift costs, panel weight and cost, computing power are all going in the right direction to improve the space-solar economic equation. As for space, a few square miles is trivial to find a place for.
Further, the usual bugaboos about "How do you get it down here?!" (microwaves to high-capacity receivers) can be circumvented entirely if you use the power in space e.g. in AI-training compute centers also in orbit.
Ground based solar has very little flaws.
Its cheap (its just silicium plates), we will have organic based systems in the future. You will be able to print it in the future.
Efficency is huge. We have so much unused roof space, its ridicoulous. parking spots, house roofs, commercial building roofs.
Why would you think its smart to send computers, which need cooling, up to use the energy over there? Do you know how hard it is to radiate heat away in space?
Its cheap (its just silicium plates), we will have organic based systems in the future. You will be able to print it in the future.
Efficency is huge. We have so much unused roof space, its ridicoulous. parking spots, house roofs, commercial building roofs.
Why would you think its smart to send computers, which need cooling, up to use the energy over there? Do you know how hard it is to radiate heat away in space?
All the usual 'obvious' points; all wrong.
Rooftop solar is pointless. Roofs don't scale; roofs are not optimally placed; roofs are hard to reach; roofs are not engineered to support the load or hardware. Open cheap unobstructed ground near a grid with clear access are optimal. Roofs are exactly zero of those.
Efficincy is 50% at best - the daily occurrence of the terrestrial eclipse known as 'night'? Remember?
Any panel argument is the same in space. Don't know what that point was about.
Using energy near the generation point is optimal. The heat argument is good; it goes double for a planet that's already heating up and causing problems. Get that shit away from our ecosystems.
Any advantage of ground-based solar is eroding daily with advances in lift cost, land price rises, congestion in cities. It's only a matter of time and money.
Rooftop solar is pointless. Roofs don't scale; roofs are not optimally placed; roofs are hard to reach; roofs are not engineered to support the load or hardware. Open cheap unobstructed ground near a grid with clear access are optimal. Roofs are exactly zero of those.
Efficincy is 50% at best - the daily occurrence of the terrestrial eclipse known as 'night'? Remember?
Any panel argument is the same in space. Don't know what that point was about.
Using energy near the generation point is optimal. The heat argument is good; it goes double for a planet that's already heating up and causing problems. Get that shit away from our ecosystems.
Any advantage of ground-based solar is eroding daily with advances in lift cost, land price rises, congestion in cities. It's only a matter of time and money.
[deleted]
Space-based will by necessity be centralised. Some businesspeople like that kind of thing.
> commercial building roofs.
And southern walls.
And southern walls.
We don't need open ground near cities to put square miles of solar farms. Why would you do that? We have long-distance transmission lines. https://en.wikipedia.org/wiki/Pacific_DC_Intertie is 3GW from The Dalles Oregon to Los Angeles (as well as other parts of the west).
Putting AI training in space is daft. Heat dissipation is the problem (on top of gravity)
Putting AI training in space is daft. Heat dissipation is the problem (on top of gravity)
> can be circumvented entirely if you use the power in space e.g. in AI-training compute centers also in orbit.
In addition to power requirements and data transfer, I always thought that the main logistical issue with in-orbit computers was heat dissipation. If you have a need for compute in orbit (let’s assume this is true), you’d still need a way to dissipate heat. But this isn’t something that can happen easily in space.
(But it makes me wonder if you could have a Peltier generator attached to a hot chip to remove heat and “recycle” some of that energy back into electricity… not that it would help too much with the other issue with compute in orbit - data transfer)
In addition to power requirements and data transfer, I always thought that the main logistical issue with in-orbit computers was heat dissipation. If you have a need for compute in orbit (let’s assume this is true), you’d still need a way to dissipate heat. But this isn’t something that can happen easily in space.
(But it makes me wonder if you could have a Peltier generator attached to a hot chip to remove heat and “recycle” some of that energy back into electricity… not that it would help too much with the other issue with compute in orbit - data transfer)
Peltier gives you energy in exchange for making heat transfer worse. Or you can make heat transfer better by paying a bit of energy. The exchange rate is very poor in both directions.
I know they are very inefficient, but are they more inefficient at heat transfer than the alternative of radiant cooling? I have no idea. I know they are used for electricity generation on some other spacecraft, but I always thought it was because it was a method of last resort. But I had never considered if a Peltier would work for cooling.
Peltiers are never an alternative to radiant cooling. They do not get rid of heat, they pump it from one side to another (if you apply power) or resist its flow (if you extract power -- this is what RTGs do). You still have to get rid of the heat when it reaches the other side of the Peltier.
forgive my ignorance on this q. I always assumed based on movies that the temperatures in space were very cold (like near absolute zero). So wouldn't putting a hot data center in space just dissipate heat? Do shuttles and space stations not radiate heat?
there is no air or medium for conductive transfer, it's purely radiative. The shuttle used it's very large doors as radiators, as far as I know. The point is that you need a lot more surface area , and that it needs to be unobstructed (since it's literally radiating out, no convention to transfer in cool air/water/medium)
> even efficiency is poor.
Not really. The atmosphere does reduce solar energy at the surface, but the fact we're 1 AU from the sun is the major reason we receive so little power.
The costs of putting things into orbit and maintaining things in orbit are unlikely to ever overcome the atmospheric difference.
Plus, on the surface of the Earth, you get convective cooling in atmosphere "for free." Good luck keeping your panels cool on orbit.
Not really. The atmosphere does reduce solar energy at the surface, but the fact we're 1 AU from the sun is the major reason we receive so little power.
The costs of putting things into orbit and maintaining things in orbit are unlikely to ever overcome the atmospheric difference.
Plus, on the surface of the Earth, you get convective cooling in atmosphere "for free." Good luck keeping your panels cool on orbit.
...and today somebody posts a WSJ article on exactly this subject.
I listened to a podcast[1] a few months ago which proposed the (IMHO) more innovative idea of using giant, ultra-light foil mirrors in space to sell sunlight to existing solar farms at night. Aetherflux seems to be using the more traditional solar panels + IR laser approach, which seems harder to justify the cost of compared to batteries.
[1]: https://firstprinciples.fm/episodes/8-ben-nowack-selling-sun...