Is It Possible to Beam Solar Power From Outer Space? (cnn.com) 130
"[F]or years it was written off," writes CNN. " 'The economics were just way out,' said Martin Soltau, CEO of the UK-based company Space Solar.
"That may now be changing as the cost of launching satellites falls sharply, solar and robotics technology advances swiftly, and the need for abundant clean energy to replace planet-heating fossil fuels becomes more urgent." There's a "nexus of different technologies coming together right now just when we need it," said Craig Underwood, emeritus professor of spacecraft engineering at the University of Surrey in the U.K. The problem is, these technologies would need to be deployed at a scale unlike anything ever done before... "The big stumbling block has been simply the sheer cost of putting a power station into orbit." Over the last decade, that has begun to change as companies such as SpaceX and Blue Origin started developing reusable rockets. Today's launch costs at around $1,500 per kilogram are about 30 times less than in the Space Shuttle era of the early 1980s.
And while launching thousands of tons of material into space sounds like it would have a huge carbon footprint, space solar would likely have a footprint at least comparable to terrestrial solar per unit of energy, if not a smaller, because of its increased efficiency as sunlight is available nearly constantly, said Mamatha Maheshwarappa, payload systems lead at UK Space Agency. Some experts go further. Underwood said the carbon footprint of space-based solar would be around half that of a terrestrial solar farm producing the same power, even with the rocket launch...
There is still a huge gulf between concept and commercialization. We know how to build a satellite, and we know how to build a solar array, Maheshwarappa said. "What we don't know is how to build something this big in space..." Scientists also need to figure out how to use AI and robotics to construct and maintain these structures in space. "The enabling technologies are still in a very low technology readiness," Maheshwarappa said. Then there's regulating this new energy system, to ensure the satellites are built sustainably, there's no debris risk, and they have an end-of-life plan, as well as to determine where rectenna sites should be located. Public buy-in could be another huge obstacle, Maheshwarappa said. There can be an instinctive fear when it comes to beaming power from space.
But such fears are unfounded, according to some experts. The energy density at the center of the rectenna would be about a quarter of the midday sun. "It is no different than standing in front of a heat lamp," Hajimiri said.
The article argues that governments and companies around the world "believe there is huge promise in space-based solar to help meet burgeoning demand for abundant, clean energy and tackle the climate crisis." And they cite several specific examples:
"That may now be changing as the cost of launching satellites falls sharply, solar and robotics technology advances swiftly, and the need for abundant clean energy to replace planet-heating fossil fuels becomes more urgent." There's a "nexus of different technologies coming together right now just when we need it," said Craig Underwood, emeritus professor of spacecraft engineering at the University of Surrey in the U.K. The problem is, these technologies would need to be deployed at a scale unlike anything ever done before... "The big stumbling block has been simply the sheer cost of putting a power station into orbit." Over the last decade, that has begun to change as companies such as SpaceX and Blue Origin started developing reusable rockets. Today's launch costs at around $1,500 per kilogram are about 30 times less than in the Space Shuttle era of the early 1980s.
And while launching thousands of tons of material into space sounds like it would have a huge carbon footprint, space solar would likely have a footprint at least comparable to terrestrial solar per unit of energy, if not a smaller, because of its increased efficiency as sunlight is available nearly constantly, said Mamatha Maheshwarappa, payload systems lead at UK Space Agency. Some experts go further. Underwood said the carbon footprint of space-based solar would be around half that of a terrestrial solar farm producing the same power, even with the rocket launch...
There is still a huge gulf between concept and commercialization. We know how to build a satellite, and we know how to build a solar array, Maheshwarappa said. "What we don't know is how to build something this big in space..." Scientists also need to figure out how to use AI and robotics to construct and maintain these structures in space. "The enabling technologies are still in a very low technology readiness," Maheshwarappa said. Then there's regulating this new energy system, to ensure the satellites are built sustainably, there's no debris risk, and they have an end-of-life plan, as well as to determine where rectenna sites should be located. Public buy-in could be another huge obstacle, Maheshwarappa said. There can be an instinctive fear when it comes to beaming power from space.
But such fears are unfounded, according to some experts. The energy density at the center of the rectenna would be about a quarter of the midday sun. "It is no different than standing in front of a heat lamp," Hajimiri said.
The article argues that governments and companies around the world "believe there is huge promise in space-based solar to help meet burgeoning demand for abundant, clean energy and tackle the climate crisis." And they cite several specific examples:
- In 2020 the U.S. Naval Research Lab launched a module on an orbital test vehicle, to test solar hardware in space conditions.
- This year Caltech electrical engineering professor led a team that successfully launched a 30-centimeter prototype equipped with transmitters — and successfully beamed detectable energy down to earth.
- In June the U.K. government announced over $5 million in funding to universities and tech companies "to drive forward innovation" in the space-based solar sector.
- The U.S. Air Force Research Lab plans to launch a small demonstrator in 2025.
- Europe's its Solaris program aims to prove "the technical and political viability of space-based solar, in preparation for a possible decision in 2025 to launch a full development program."
- One Chinese spacecraft designer and manufacturer hopes to send a solar satellite into low orbit in 2028 and high orbit by 2030, according to a 2022 South China Morning News report.
Do these people not watch science fiction? (Score:2)
All they need to do is watch Gundam 00 to see how vast solar arrays in space can provide limitless energy to the world.
Re: Do these people not watch science fiction? (Score:2)
Re: (Score:3)
Or they can just play Fallout: New Vegas.
just trun on no disasters and it's fine! (Score:2)
just trun on no disasters and it's fine!
Probably possible, not worth the effort (Score:3)
Re: (Score:2)
Space based solar works 24/7 if you position it correctly.
Re: (Score:2)
I'm always astounded people plaster arable land with solar panels. Just because you may not be farming it right now doesn't mean that growing grass or trees aren't making their own contribution to the globe.
Absolutely the only places solar panels should be installed is on rooftops, concreted areas, and desert. Anywhere the sunlight does not have a useful purpose.
Anywhere anything biologically benefits from sunlight should not be covered in solar panels.
On the topic of beaming power from space - this i
Re: (Score:2)
I'm always astounded people plaster arable land with solar panels. Just because you may not be farming it right now doesn't mean that growing grass or trees aren't making their own contribution to the globe.
Absolutely the only places solar panels should be installed is on rooftops, concreted areas, and desert. Anywhere the sunlight does not have a useful purpose.
Anywhere anything biologically benefits from sunlight should not be covered in solar panels.
You can do both at once: https://en.wikipedia.org/wiki/... [wikipedia.org]
Re: (Score:2)
https://reneweconomy.com.au/so... [reneweconomy.com.au]
“The sheep we are running have actually done better than the sheep under normal farming conditions,” says Keith.
Re:Probably possible, not worth the effort (Score:4, Insightful)
No, h2 isn't hard to store. No, h2 isn't hard to make. No, h2 isn't hard to ship. How do people think h2 cars are being filled, if all these things are "impossible"?
If all this is true what's the holdup? What's the solution for storage outside of pressure vessels or cryogenics? What's the solution long term to embrittlement? What is the leakproof vessel and pipe material we use that also doesn't embrittle? I'm not saying there isn't progress on these issues but they are as I understand it, still issues.
Overall though I do like hydrogen a lot and I think it has big potential to displace diesel in commercial and industrial equipment but i've always felt it's a cart before the horse solution because a huge part of the appeal is it can be made by cracking water but to do that reasonably we need gobs and gobs of cheap clean power, we're just not there yet.
On top of that for passenger vehicles? It's over for hydrogen, it's just too much brand new infrastructure and too many unknowns at the scale of gasoline. With EV's the infrastructure is already there, we just need to expand and improve it.
Re: (Score:3)
Re:Probably possible, not worth the effort (Score:4, Informative)
For transport trucks, I almost certainly agree as I already stated. They have their own specialized infrastructure and dynamics that are more suited to the specialized setups needed for hydrogen. A truck stop and a company depot can put the investment into the necessary backend to support it.
For passenger vehicles H2 didn't need anyone to kill it, as even Toyota recognizes:
Nakajima told the publication that hydrogen is better suited for cars that mainly travel between two locations, like commercial vehicles. Their often limited and specific use would make it easier to provide stable refueling options. Toyota and Isuzu announced earlier this month that the two would develop light hydrogen fuel-cell trucks together. [motor1.com]
- H2 will always need specialized gear to transport and dispense, be it high pressure, cryogenic or some sort of chemical. It can never be as simple as gasoline or electricity. That means building it all from scratch.
- H2 still doesn't have a green generation source. If you just crack methane its about 65-75% efficient. We are reaching efficiency ratings of 50-65% on most gas turbines so it's barely better than just burning that gas for electricity. Combine that with the transport and storage costs for hydrogen and you are likely at a loss. This only get's worse on a grid that has renewables on it.
- Lets not also forget that while EVs have supply questions about lithium and other feedstocks H2 has this as well with platinum, palladium and other rare metals needed for manufacture.
Most places in the world have electricity already, what percentage has access to hydrogen production, transport and refueling?
If you hate EVs and want a dead-end tech to parrot instead you could at least choose synthfuels which actually solve for the infrastructure problem (but have fallen flat on production, same problem, needs tons of cheap power).
Re: Probably possible, not worth the effort (Score:2)
Hydrogen is better than EV but it still is about 4-5x worse in energy density than modern fuel just for the fluids, the pressurized tanks, fuel lines etc add a significant amount of weight and risk too and the current efficiency of hydrogen fuel cells are nowhere near a diesel engine. So youâ(TM)re still having the same problem of âthe fuel is too heavy in proportion to its energy productionâ(TM). Again, this would be better suited for passenger vehicles which are mostly empty.
Re: (Score:2)
If that was 2006 and somebody came up with an energy efficient H2 production process I imagine we would be looking at a hydrogen economy today. They didn't so for passenger vehicles, families, commuting and such, it's over, there's just no reason to switch gears now, it'll never catch up and never be worth the investment
Hydrogen [Re:Probably possible, not worth the ...] (Score:2)
society is on an EV stampede that has a lot of momentum and by the nature mentioned by the OP they are trying to kill H2 because of loud senseless idiots who continue to slag it.
Hydrogen has a lot of problems with storage: it needs either enormous tanks, insanely high pressure tanks, or cryogenic tanks. Unless somebody comes up with a magic solution to these problems, it is not going to be practical for cars.
Now, hydrogen very plausibly could be a key component of carbon-dioxide-free energy infrastructure... but not for cars.
So, no, hydrogen is not being killed because EV fanatics are "slagging it"; hydrogen and EVs are different markets.
Re: (Score:2)
What's the solution for storage outside of pressure vessels or cryogenics?
Metal Hydrates (e.g. 1:3 palladium/silver alloy).
Re: (Score:2)
That was the answer in the 90s, too... where are they?
Re: (Score:2)
To speak to that, solar panels in Africa allows for h2 generation, and export via pipeline to all of Europe
I think you are missing the point that even if the panels were for hydrogen, producing nations would want to set the price. European nations are unwilling to allow such. The issue is technical for the moment, but the broader issue of sovereign nations still lingers no matter what tech you toss at it.
Re: (Score:3)
No, h2 isn't hard to store.
H2 isn't hard to store, unless you want good volumetric efficiency. Then it's both difficult and expensive.
No, h2 isn't hard to make.
H2 isn't hard to make, unless you want good energy efficiency and low ecological impact. Then it's at least difficult or expensive.
No, h2 isn't hard to ship.
H2 isn't hard to ship, unless you want to do it as cheaply as we ship hydrocarbon fuels, or you want to do it without leaks (keeping in mind that the GWP of H2 is 8 times that of CO2.) Then it's both difficult and expensive.
How do people think h2 cars are being filled, if all these things are "impossible"?
Poorly, and with at least two filling station expl
Re: (Score:2)
How long does excess H2 stay in the atmosphere?
Re: (Score:2)
Good to see Europe attempting to spin their need to subjugate African nations as some sort of positive.
I'd overlooked launch cost changes (Score:3)
I've always been a champion of space-based solar. Once you have your station in place, it's zero-carbon power until the platform fails. It's incredibly safe to beam power from the satellites to a rectenna farm - the systems are self-aiming.
Basically, if you can get a microwave beam and a large solar array into high orbit, you've just given 'free' power to wherever that beam points. No dams flooding ecosystems, no nuclear waste accumulation, no CO2 release, no vast areas of land covered with solar panels, and no dependence on season, time of day, or weather.
If the revolution in space access SpaceX started has brought the launch price down to something anywhere near competitive, we should be building experimental space power systems right now.
Re: I'd overlooked launch cost changes (Score:3)
Itâ(TM)s not free unless you overlook the costs of launch, maintenance, upkeep, repairs, and eventual replacement. Even with all of those costs accounted for, it still might be worthwhile, but then again it might not be.
Iâ(TM)m particularly wondering about the longevity of these systems in the face of space debris and/or deliberate attack. If/when your nation starts to rely on them, they would become a high-value target for hostile nations and they would be very difficult to defend.
Re: (Score:2)
While most of our energy will be extremely cheap renewables in future, there will be maybe 5% that is more expensive. It will require pricey things like fossil fuels with carbon capture, nuclear, or space based solar.
As for security, all other centralised generation makes an easy target that is hard to defend too. At least an attack won't cause a nuclear accident.
Re: (Score:2)
Beaming microwave power isn't new, but it's not lossless. I believe Japan did a 10km experiment and it was over 90% loss. Being a signal isn't the same as beaming power; i.e. the Voyager signals from edge of solar system. With signal you just need a sensitive enough antenna to get the info. If the goal is getting useful power out, then the strength of the received signal matters. Inverse
Re: (Score:2)
>This would also need to be in geo stationary orbit
Why? For full infrastructure with 100% coverage you could have multiple satellites switching receiving stations as they orbit. They really only have to be high enough you don't have to constantly boost them due to atmospheric drag, and you could be 1/30th the way to GEO and have that benefit.
Re: (Score:2)
I think they are right on this one. It's hard to see the advantage of easier heavy lift and serviceability in LEO being enough to justify the loss of availability. GEO Orbital solar works at night and is only eclipsed for brief periods per day (around local midnight, averaging 30 minutes) for about a month before and after each equinox. In LEO your availability goes way down, and you also have larger headaches of drag, pointing and beamforming to a variable distance receiver.
Re: (Score:2)
Point being there's MEO, and that's a lot of range to play with.
Re: (Score:2)
It's a fabulous idea that's gone from pure fantasy to maybe technically doable but ridiculously expensive but still is beyond our realistic means when other options exist for much less.
Re: (Score:2)
The advantage of being in a lower orbit is much easier pointing and especially beam forming. You need a much smaller antenna in orbit to hit a given size antenna on the surface.
Re: (Score:2)
Is antenna volume actually a limiting factor in space?
Re: (Score:3)
Re: (Score:2)
Not really SpaceX's thing. Starlink is designed to create demand for launches by polluting LEO with thousands of satellites. Cybertruck was supposed to make the steel needed for Starship cheaper by increasing demand.
Basically Musk only cares if it furthers his goals, and space based solar doesn't need as many launches as spamming LEO for internet access. Maybe if Starship needs a Shuttle style cargo bay or something like that.
Re: I'd overlooked launch cost changes (Score:2)
Re: (Score:2)
Re: (Score:2)
Not quite that simple (Score:5, Informative)
That $1,500 per Kg is for low-earth orbits which are unsuitable for beaming power back to earth because they can't focus their energy on a single location on the planet's surface.
The price I saw quoted for boosting payloads into geostationary orbits (which is a lot further out and requires a lot more energy) was $11,300 per Kg (cite [wikipedia.org]) which is a *lot* more expensive.
Re: (Score:3)
>The price I saw quoted for boosting payloads into geostationary orbits (which is a lot further out and requires a lot more energy) was $11,300 per Kg (cite) which is a *lot* more expensive.
SpaceX was publishing $67m to put 8300kg into GTO, or $8k/kg in 2022, and is promising its next generation rocket will cut that much further.
GTO does mean your payload has to have some thrust capacity of its own to circularize its orbit to a more standard GEO, and I'm afraid I do not have the ability to do the math on
Re: (Score:2)
Well, if you have to have multiple stations, then your weight per watt - and solar-cell costs per watt - just tripled or whatever.
About that weight: never mind "normal" solar panels that are 10kg/m2 at minimum. "Thin Film" are wikipedia'd at 7-10 oz. Let's say 5 oz in future, to allow for progress. That's 1.3kg/m2. (that means squared, tiring to type ^ all the time).
And let's drop launch costs to $1000/kg, I want to be sporting. So $1300/m2 in space. 1M m2/km2, so 1.3Billion/km2
We will wave awa
Re: (Score:2)
>, if you have to have multiple stations, then your weight per watt - and solar-cell costs per watt - just tripled or whatever.
If you put up multiple satellites and build multiple receivers, your mass per watt and cost per watt remain the same... you're just building a bigger base network.
Re: (Score:2)
GTO does mean your payload has to have some thrust capacity of its own to circularize its orbit
The photovoltaic film would double as a solar sail. It is large and light-weight.
Re: (Score:2)
That $1,500 per Kg is for low-earth orbits which are unsuitable for beaming power back to earth because they can't focus their energy on a single location on the planet's surface.
The price I saw quoted for boosting payloads into geostationary orbits (which is a lot further out and requires a lot more energy) was $11,300 per Kg (cite [wikipedia.org]) which is a *lot* more expensive.
What about a large space based solar array combined with a battery bank/super capacitors and a good phased array xmit antenna so you can aim and jam or fry enemy satellites yet innocently claim it’s a power station to avoid the space weapons treaties? Looks like it would make an excellent weapon far before it would bring any kind of reasonably cost bulk power back down to earth.
Re: (Score:2)
Why not just pull a Starlink and stop worrying about 1:1 relationships with fixed points on earth?
Re: (Score:2)
The problem with LEO is not aiming, it is a case of the generator is in the shadow of the Earth.
At that point you lose the one adventage over ground based solar.
If you don't see the problem with this... (Score:2)
Doesn't the sun already do this? (Score:5, Informative)
We have this giant ball of fire in the sky, that constantly beams power down to earth, in the form of heat.
But what about at night, or when it's cloudy? Yes, there's a potential for orbital power stations to cover those scenarios. But the question is not, "Is it possible?" but rather "Is it cheaper than building earth-based solar power generators, combined with power storage for nighttime." If it's not cheaper, then what's the point, exactly?
And then there's the air pollution caused by all those rocket launches, which is not insignificant.
Re: (Score:3)
I could see it for certain locations, such as arctic/antarctic bases etc where you simply can't do solar. At that point the 'costs' of ground based power are higher to make a space based concept a little more palatable - but even so, panels everywhere else and diesel gens for very small bases still comes out cheaper even if a little co2 is released. Or even off site solar produced hydr
Re: (Score:2)
I could see it for certain locations, such as arctic/antarctic bases etc where you simply can't do solar.
That’s what an RTG battery excels at already, for far less cost, even in snow or clouds which can affect the efficiency of beaming down power. Probably something like 1,000 to 10,000 times cheaper per watt and runs for years to decades.
Seems pointless then... (Score:2)
But such fears are unfounded, according to some experts. The energy density at the center of the rectenna would be about a quarter of the midday sun. "It is no different than standing in front of a heat lamp," Hajimiri said.
If it only has 25% the energy density of solar... then we would just use solar, no? There's no point in collecting the energy in space and beaming it down to earth if we can only transmit 25% of what the sun does. It would be simpler just to use more solar panels on the surface then.
Any microwave beaming of power back to the earth, ABSOLUTELY will have enough energy density to be deadly, otherwise the level of energy we are getting is negligible and it would be pointless.
Re: (Score:2)
>Any microwave beaming of power back to the earth, ABSOLUTELY will have enough energy density to be deadly, otherwise the level of energy we are getting is negligible and it would be pointless.
The boffins insist this intuitive answer is absolutely incorrect, and I suspect they know more about it that either of us.
Re: (Score:2)
A few clarifications.
The big reason for building orbital solar is that it works at night, when it rains, and when it snows. The availability of light to panels on the surface is under 50% accounting for weather and nighttime. Above the atmosphere at GEO it's 95% and you get significantly more power per square meter too. The 5% outages are due to eclipses, and those are mathematically predictable.
The energy density delivered to the rectennas on earth is a function of how clever we can be with beamforming
Re: (Score:2)
No.
The 25% energy density is concentrated in the range of wavelengths your rectenna is most efficient at absorbing. Solar energy is not, and worse, the wasted solar energy heats up your cells which makes them less efficient.
Despite your confidence, there's a wee bit more to it than you think.
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
You forgot that the microwave energy density is only 1/4 that of sunlight, so you need to divide your "efficiency" of microwave energy reception by 4 again...
And that's just the raw transfer efficiency. I'm willing to bet that *launching satellites into orbit* has such a massive overhead cost compared to slapping some panels down in a desert, that we can put the nail in the coffin here.
Re: (Score:3)
Solar panels are 15% efficient, and only get effective use 25% of the day. So 25% vs 3.75% (.15x.25). I am still skeptical of the costs though.
Try not to do low-balling, it is irritating. Commercially used panels are in the range of 18-22%, so lets take a current average of 20%, not the incorrect 15%, and over time (remember you are comparing it to pie-in-the-sky systems that won't exist for a decade or more) the steady improvement of panel efficiency makes a long term target of 25% realistic (laboratory silicon has broken 30%).
Re: (Score:2)
The solar panel I am looking at now is
1763mm x 1040mm and is 370watts
370 watts / (1.76m * 1.04m /1 m^2 * 1361 watts) = ~15%
The cells may be 20% but the panel is not filled with cells.
Over 50% loss (Score:2)
This came up years ago on /. and I stopped to look up the papers on losses from ...and they add up to over 50%. So, ground-based loses 75% (dark half the time, and half more lost unless you expensively point the panel at the sun all the time, then there's weather.)
a) electricity to microwaves
b) loss in transmission
c) microwaves to electricity
So, space-based produces 2X as much power for the same acreage of cells.
If you can launch 100 km^2 into space for the expense of where you were going to put 200 km^2
Re: (Score:2)
> If you can launch 100 km^2 into space for the expense of where you were going to put 200 km^2 on the ground where the rectenna would have been, you can break even.
Ground is harder to come by in the middle of the ocean.
But maybe they should use sails instead of solar microwaves from space.
The Ground Exists (Score:2)
You know the ground exists, right? You can just build the solar panels on the ground. What little you gain by putting things in space doesn't offset the cost. Are thermal batteries and liquid air batteries (basically anti-thermal batteries) expensive at grid scale? Yes. Are they more expensive than lifting all that mass of solar panels into space? Hell-fucking no. Every plan on the subject ever put forth always ignores the much cheaper and easier alternative because the architect of the plan just wants his
Is It Possible to Beam Solar Power.... (Score:2)
Bullshit Bulletpoints (Score:4, Interesting)
That was testing solar panel tech that's used to power satellites, not stuff on the ground.
This is otherwise known as a radio transmitter and a rectifying antenna. You can buy them at Radioshack. Well, no you can't. But you could buy them at Radioshack back when Radioshack sold actual radio electronics equipment.
That's a Tory grift to funnel money to supporters. Also known as a kickback.
From the article: "The goal of SOLARIS is to prepare the ground for a possible decision in 2025 on a full development programme by establishing the technical, political and programmatic viability of Space-Based Solar Power for terrestrial clean energy needs."
It's a proposal to begin a fact finding committee to organize an investigation into the possibility of a research program. Which is bureaucratic-speak for, "This is how we waste money for twelve years then say nothing came of it."
Same as above.
This is just a scam. It might actually just be propaganda; it might just be a scam without a scam.
There is no need for it. (Score:2)
Re: (Score:2)
In orbit neither night nor season need affect you.
Overnight and dunkelflaute surviving storage are hard.
Re: (Score:2)
Re: (Score:2)
Ironically the best place to beam the power to is... a solar installation, because you can design the solar panels to also be receiving rectennas.
It's not an either-or, you can have both.
If the Master allows it (Score:3)
There is no master but Master, and QT-1 is His prophet .
Things that cross the beam (Score:2)
Re: Things that cross the beam (Score:2)
Perhaps, planes & such will learn to avoid those powerful beams from outer space - the birds? Well, they'll only make that mistake once...
Re: (Score:2)
IIRC these are football-shaped microwaves, not space lasers.
Betteridge's law of headlines says: No (Score:2)
Geez... it's like the person who posted this has never read Slashdot before.
Almost every question asked in a Slashdot headline ends up getting answered in a negative!
Maybe (Score:2)
If thin film PV with no protective covering can survive in space, then you can put a whole lot of it there with not a lot of weight. Not solar panels, just a couple of kilometre of solar ribbon kept taught by centrifugal force. Solar wind is probably going to implant and slowly destroy the PV though, maybe you could string some wires to divert the charged particles with an electrostatic field? Might also help with the amount of solar wind force it catches.
Then you just need a klystron and a huge rectenna ar
i doubt it would be workable (Score:2)
Re: i doubt it would be workable (Score:2)
Didn't Darth Vader do that from the Death Star? Wait, I don't think the Death Star was solar powered, knowing his evil mind it probably ran on fossil fuel and polluted the Galaxy with greenhouse gasses...
Re: (Score:2)
Most likely a Klystron sending microwaves to a field of rectennas.
Klystron is the only way to get the needed beam quality AFAICS.
Is It Possible to Beam Solar Power From Outer Spac (Score:2)
In a word, yes - the Sun has been doing just that since, well, forever!
The deadly sun laser... it came from outer space! (Score:3)
Just Stupid (Score:2, Interesting)
We have a hard enough time shedding the energy that is already hitting us from the sun, and they want to double down and increase the amount of energy the earth has to absorb from the sun. Just stupid.
We need to cool the earth, so what do they propose? Gathering up huge amounts of energy in space, finding a way to concentrate it, and then send it to earth to be turned into mechanical energy and more heat (that pesky nothing is 100% efficient thing). On top of the energy that is already striking the earth.
Death ray (Score:2)
If you have a way to collect and beam down high power energy beams in some focused way, so the collector on the ground is some reasonable size, you have an orbital energy beam that can incinerate whatever you point it at.
You probably don't want one of those up there. Even if the people who control it are friendly, have you seen the quality of spacecraft data link security lately?
You're proposing the terror weapon to end all terror weapons.
You're better off making a ground based solar concentrator rather tha
Caltech beams "detectable" energy from space. (Score:2)
The first satellite ever launched, Sputnik, successfully beamed "detectable" energy down to Earth.
The Caltech test did the same thing, at about the same power level, 66 years later.
They managed to word the press release in a way that made it sound impressive, but it wasn't. They detected a radio signa
yes (Score:2)
Set The World On Fire (Score:2)
Isn't this what the "Microwave Power Plant" did in SimCity 2000? A solar collector in orbit would power a microwave laser and "beam" the power down to a receiver in your city. Occasionally the beam would "miss" the receiver and start a huge fire... I wouldn't want to live anywhere near one of those things.
The math is simple (Score:2)
Let's assume that the only advantage of space-based is that it can produce stable power 24/7 from geostationary orbit and thus doesn't need storage (any differences in efficiency or amount of power is simply a potential mass reduction). How much would a traditional land-based photovoltaic and storage system cost that can provide constant stable power 24/7 (meaning it has to be over-spec'ed to provide a certain minimum amount of power even on days with poor weather conditions)? Your space-based power system,
Re: (Score:2)
Waste heat [Re:Yes] (Score:2)
Wouldn't extra sunlight cause more climate change?
Not enough to notice. Turns out the heating due to the greenhouse effect from burning fossil fuel is much much larger than the waste heat of the energy production. We'd need to expand energy use by many orders of magnitude before the actual waste heat would be a problem.
Re: (Score:3)
Three words make your suggestion useless:
Inverse. Square. Law.
The further away from Earth you get, the more spread out the beam will eventually be when it hits Earth. Instead of hitting the receiver you scorch the entire city it's in.
Re: (Score:2)
Re: (Score:2)
Lasers and Masers [Re:Yes] (Score:3)
For one thing, if you can beam power in space, why float it in LEO where it has to be cognizant of debris?
Nobody knowledgable is proposing solar power satellites for terrestrial power in LEO (Low Earth Orbit). The beam time on target is too short, and the amount of time spent in the Earth's shadow is too large, among other things. Almost all the proposals are for systems in Geosynchronous Earth Orbit.
You can cut down on the spread considerably if you use a laser.
I work on laser power beaming. It has advantages in beam spread, but lasers are much less efficient that microwaves, both in transmission and in receiving. In practical terms, this means you will need very large
Re: (Score:2)
Re: Yes (Score:2)
Iâ(TM)d love to see space solar but the economics seems difficult
Re: Yes (Score:2)
Re:Yes (Score:4)
That sounds really complicated.
Really really really complicated.
Sure it's technically possible, but compare to the alternative: putting solar panels right here on earth where they're cheap to transport, easy to install, easy to connect to the grid, and easy to maintain if anything goes wrong. And when they reach the end of their useful lifespan you take them down, recycle them, and put up new ones.
They'll also probably last longer on earth where they aren't subject to intense heat from being so close to the sun, ionized particles, and micrometeroid impacts.
Simple solutions have a lot of advantages over complicated ones.
Re: (Score:2)
Putting them in space is less complicated. There is a lot of space in space. And rockets get it there in minutes.
Also, low Earth orbit is not closer to the sun than the Earth is. And can be kept well within Earth's magnetic field.
Another advantage of space-based solar power plants is that they don't have to deal with a day-night cycle. They can harvest daylight around the clock with no temperature shifts. So the panels are likely to last a lot longer in space.
And connecting them to the grid is only a m
Re: (Score:2)
You're mixing up low Earth orbit (LEO) with geostationary orbit (GEO). A satellite in LEO is only about 1000 km up. That's much smaller than the Earth's radius, so it spends almost as much time in darkness as if it were on the ground. It's also useless for space based power because it's constantly moving relative to the ground.
Space based power requires putting the solar panels in GEO so they maintain their position above the receiving station on the ground. That's 35,786 km up. It is much much more ex
Re: (Score:2)
I think people may be using solar power in space in space stations to manafacture things for Earth (Which is space based solar). But they will not feed the power into Earth grids.
Re: (Score:2)
While there is ample sunshine in those locations, they do get really hot and heat is actually bad for solar panels. https://www.greentechrenewable... [greentechrenewables.com] After you get above 77F, you start to see diminishing returns.
Re: Yes (Score:2)
Re: (Score:2)
All that energy coming down will eventually end up as heat on the earth's surface that would not have been there otherwise. The question of how much waste heat such as this contributes to warming today, as opposed to greenhouse gasses, is up for debate at this point.
No, it isn't up for debate. It can be calculated.
World energy use is about 20 TW, according to Wikipedia. Compare this to the total effective radiative forcing (ERF) of the anthropogenic greenhouse effect, 2.3 W/m^2 [www.ipcc.ch], multiplied by the surface area of the globe (510 million km^2 = 5E14 m^2), which comes to 1150 TW. So, the waste heat of energy generated is small compared to the existing anthropogenic greenhouse warming.
Re: (Score:2)
And because it is in eletricity you need even less energy use. (Although this may be balanced out by ineffeciencies in conversion)