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Not really, no

Thousands of giant mirrors could be placed in space to reflect sunlight onto solar farms.

The European Space Agency (Esa) is exploring the concept of direct sun reflection (DSR) – a technique in which sunlight would be bounced back down to Earth at dawn and dusk.

By focusing the light on pre-existing solar farms, the technique would add two hours of bright sunshine each day and boost output by 60 per cent, experts have calculated.

Why not put the solar cells into orbit then collect power 24/7?

Given panel costs, and SpaceX launch costs, we’re getting pretty close to this being economic, aren’t we? Technically, it’s possib;e, it’s whether economic of course….

44 thoughts on “Not really, no”

  1. Harry Haddock's Ghost

    You would need some kind of magic floating pylons to bring that power down to earth. Perhaps that’s where the economic argument falls over?

  2. Getting the power from orbiting solar cells to earth would need a beamed microwave power link. Generally you refer to things like that as death rays.

  3. DSR is probably overall cheaper . Guesstimate but much lower mass, easier to lift (basically mirrored plastic sheets) and only one energy conversion issue instead of two. Probably lower in-orbit maintenance as well – just keep it in place and replacements on collision damage.

    As said can leverage the on ground existing install – and for the peak evening demand – not necessarily where you’d want to end up (eg synth fuel plants somewhere remote ) but reduces initial cap ex.

    PV cells would be heavier , more expensive , have a higher maintenance cycle and need power transfer technologies – some of which would probably get a public backlash (invisible death rays from space – buy your branded tinfoil hat here) .

    Space applications could get real interesting for all sorts of areas once it reaches tipping point for heavy lifting. I would also expect that would unleash lots of interest in other ways to get heavy loads up to orbit and beyond that are currently solutions looking for a problem.

  4. Why bother with the beamed microwave? Just re-align the mirrors to fry the location of your choice.

  5. Have they thought about the consequences of beaming sunlight to area in darkness. Think of all the environmental harm. Animals having their daily cycles disrupted would trigger any environmentalist.

  6. Or they could spend the money on nuclear reactors

    Mature technology, known risks etc

    Silk purse and sows ear springs to mind

  7. But doesn’t Bill gates want to block sunlight to combat climate change? We will need some kind of grid that blocks climate sun, but allows electricty sun

  8. To get a couple of extra hours you could use a ground-based site thirty degrees of longitude away. No need to launch the panels.

    All proposed geo-engineering solutions to the non-existent problem must be subjected to the most stringent due diligence, for they are scams, dangerous or both.

  9. Pointing solar mirrors onto an Earth based solar array would be a waste of money, between the costs of launch and maintenance and losses through the atmosphere, the ROI would be gone.

    If you’re going to do that sort of thing far better to convert the energy to microwaves and transmit it down to a rural location with grid connectivity (so a pasture near an existing or previously existing power station), so Drax might be a good location.

    Then suspend a 1 KM² collector array above the pasture at a height of a couple of metres and continue to use the pasture underneath for sheep / cattle but periodically test the animals for any symptoms of microwave exposure.

    This has the advantage that you can throw a massive solar array into Geostationary orbit with a refillable fuel tank (since we’re getting to that level of maintenance in orbit technology).

    Initially, you’ll have to launch the power collector from Earth using Starship, but once lunar development moves on a pace, just build the solar array from Lunar Regolith, mate with a prebuilt power controller from Earth and launch from the surface of the moon, allowing a much larger solar array to be deployed into the same Geostationary orbit while the old one is retired.

    Hard part would be ensuring that the microwave beam is limited to the centre of the 1 KM² array and if the transmission starts to move to the edges of the array, it is automatically cut off to prevent blasting the countryside with microwaves.

    Even the watermelons would struggle objecting to that one. Maybe some vegan complaints about the sheep / cows, I guess.

  10. Thousands of giant mirrors could be placed in space to reflect sunlight onto solar farms.

    It is remarkable what overcomplicated bullshit people come up with to address the self-imposed problems of idiot schemes. Why not just admit that solar farms don’t work in northern Europe?

  11. Long term ( centuries?) there may be much more utility in shifting smelting operations to space using all that “free” energy to do the desired change in physical properties outside the atmosphere and use the refined product up there.
    I’ve always assumed it should be cheaper to bring stuff down to earth from outside than it is to overcome gravity & boost it to orbit?

  12. But doesn’t Bill gates want to block sunlight to combat climate change? We will need some kind of grid that blocks climate sun, but allows electricty sun

    Yeah, but Bill Gates is getting to be a bit like Tony Blair in that anything that comes out of his mouth, whether idiotic or sensible is immediately repulsed by about 40% of the populace because it’s Bill Gates that’s saying it.

    Then again, since we’re currently (still) in an interglacial period, buggering about with blocking the sunlight might be an extraordinarily BAD idea. Bill Gates and the rest of the “Optimum Population Trust” crowd might see the advantages of killing off the masses with a sudden glacial event, but I’m against it myself.

    If we’re going to bugger about with the environment, why not go back to doing seeding the plankton of the Northern Pacific? Removes massive amounts of CO² and gives us bumper Salmon harvest.

    https://www.forbes.com/sites/timworstall/2014/04/28/iron-fertilisation-of-the-oceans-produces-fish-and-sequesters-carbon-dioxide-so-why-do-environmentalists-oppose-it/

  13. Long term ( centuries?) there may be much more utility in shifting smelting operations to space using all that “free” energy to do the desired change in physical properties outside the atmosphere and use the refined product up there.
    I’ve always assumed it should be cheaper to bring stuff down to earth from outside than it is to overcome gravity & boost it to orbit?

    That’s exactly the point made by Jeff Bezos, shift heavily polluting industries to the moon supported by Lunar Solar and Lunar Nuclear power for the energy and don’t worry too much about the consequences since there’s no atmosphere to propagate it and any serious waste can just be buried in a crater and left there.

    Not sure I buy the entirety of that argument, sounds a bit 19th Century to me, but there is some merit to moving heavy industrial production to the moon instead of China.

  14. I love a Bond as much as the next chap but when beaming power down from space we would presumably pick a frequency which would not resonate water molecules, and therefore not be deadly, like the ones we fling stuff around with right now, e.g. mobile phone signals. However it’s still a nuts idea, surely nuclear is the inevitable way to go, as we have been almost concluding for the last 75 years.

  15. surely nuclear is the inevitable way to go, as we have been almost concluding for the last 75 years

    Sure. If the NIMBY’s and the governments own regulations would allow us to actually build nuclear power stations. We’re currently running at about 1 nuclear power station per decade on average, which is below the decommissioning rate.

    So in the absence of ACTUAL nuclear power stations being bought into operation any time soon, I’ll take space lasers as an alternative to sweet phuq all and shivering in the dark.

    Although, given that a Labour government seems imminent, we might not get any option other than “shivering in the dark”.

  16. Although, given that a Labour government seems imminent, we might not get any option other than “shivering in the dark”.

    There’s always the option of warming our hands over the embers of the Palace of WEFminster.

  17. If you’re going to use common sense John, you could just ramp up drilling in the North Sea to make up for the exhaustion of the present fields. Or just dig up all the coal you’ve been sitting on for the last 300 million years.

    Of course, if you consider this too blasphemous you could just buy your coal from Oz. We need to export lots of the stuff to pay for all our windmills and solar panels.

  18. “A slight case of sunstroke” by Arthur C. Clarke comes to mind.
    Well yeah. This idea goes back at least a half a century, maybe more. But actually doing it? Current state of the art is a 25 year old space station overdue for renewal & some plans to return to the moon. There might just be the capability to do this in 50 years. But why would you bother? It’s starting to look like they’ve finally got fusion cracked with several options. They achieved net power generation for several minutes with a demonstrator earlier this year.
    Think this through. For a European project, as suggested, you’d need two mirror arrays, one on the dawn side & one on the dusk side, each one operating for 30% of 24 hours. So what are they doing for the other 70%? Make sense of course if they then reflecting sunlight to somebody else’s solar farms further round the planet. It stops being a European project. Ideally you orbit the mirrors right around the planet with corresponding solar farms below & don’t need them in synchronous orbits. Far more bang for your buck. So you’re talking mirrors, space habs for the people would need to do the inevitable maintenance & repairs, turnover flights for crew reliefs. You’re contemplating orbiting a couple of million tons minimum & tens of thousands of tons a year. And current state of the art was the third test of Elon’s Starship just managed to get out of the atmosphere but failed on the controlled descent. Euros are at best a decade behind probably more like two.
    It’s just government subsidised SciFi.

  19. Think this through. For a European project, as suggested, you’d need two mirror arrays, one on the dawn side & one on the dusk side, each one operating for 30% of 24 hours. So what are they doing for the other 70%? Make sense of course if they then reflecting sunlight to somebody else’s solar farms further round the planet. It stops being a European project. Ideally you orbit the mirrors right around the planet with corresponding solar farms below & don’t need them in synchronous orbits.

    It would be idiotic to have this in Low Earth Orbit.

    Put it in Geosynchronous orbit and keep it orbiting continuously about the UK 365 days a year * it’s lifetime.

    By using focussed microwaves with a non-interfering wavelength you get maximum bank for your buck and because you are out of the Earths shadow you get 24 hour a day sunlight (assuming solar panel tracks the sun while microwave antenna is focussed on the 1KM² in the UK)

  20. Oh, and worth mentioning that if you’re contemplating operating anywhere between low earth orbit & past geostationary, you’re in the Van Allen belts so a high radiation environment. So you’re going to be needing to be orbiting a considerable mass of shielding. And I doubt something like Mylar film would last very long in the proton blizzard of the lower belt, either. High energy particles & plastics don’t get on well together.

  21. Put it in Geosynchronous orbit and keep it orbiting continuously about the UK 365 days a year * it’s lifetime. By using focussed microwaves
    Do you know what’d happen to a focussed beam of microwaves passing through that part of the earth’s magnetic field? My guess it’d bend & de-focus it highly unpredictably. It’s what it does to sun’s incoming electrons.

  22. How much larger does the array of mirrors have to be when it’s in geosynchronous orbit (36000 km) as opposed to low orbit (2000 km or less)?

    My very simple model (square of the ratio) indicates 300 or so times larger to subtend the same angle.

    Perhaps you don’t need all of that, but I suspect you need a lot in order to focus it onto the farm over that larger distance.

  23. You are all missing the easiest and most obvious answer.

    Put the clocks back two hours every night at 2am, then forwards again 2 hours at 2pm and hey presto an extra 2 hours of daytime 🙂 Simples

  24. Another thought (it’s early morning here, so my brain is slow).

    There’s already a lot of complaints about Starlink causing problems with astronomy (lots of small dots wizzing past). How much worse will it be with lots of large mirrors doing the same thing?

    And yes, if this project actually comes about it will be on SpaceX rockets. They’re the only ones who can do it cheap enough.

  25. @M
    Uh? It wouldn’t make any difference. Just make the focussing a lot trickier. The mirrors in both cases are at earth/solar orbit & get around 1.2kW insolation. You’re using the math in the wrong direction. For that you’d be increasing the area of the earthside collectors not the mirrors to intersect the beam.

  26. BIS: Pretty much nothing. Photons are only negligibly affected by magnetic fields as they have no charge, so microwave or laser beams would be fine. A partical beam of electrons would be another thing. The effect of the earth’s atmosphere would be a much bigger factor… but at least we’d have warm clouds and rain.

  27. Bloke in North Dorset

    Good luck finding enough space for a satellite that big to provide a geosynchronous orbit that can be seen from UK and then there’s all that debris and other clutter as well as malign actors wanting to disrupt our energy security plans.

  28. Can’t do any serious space engineering without a space elevator, and we’re nowhere near being able to build a space elevator.

    Because it simply costs too much to accelerate stuff to 11 km/s from the bottom of a gravity well.

    We have an effectively unlimited supply of terrestrial energy that doesn’t require putting things in orbit. Burn some fucking coal like a normal person and floodlight your farms with the cheap electricity, for example.

  29. The incoming Labour government will need to repeal the laws of thermodynamics first. Otherwise the line losses would lead to – the horror! – global warming.

  30. Why not just admit that solar farms don’t work in northern Europe?

    Because that would bring the gravy train to a shuddering halt, of course. PV (at temperate latitudes) are essentially useless as a means to reduce global CO2 emissions, but very effective at subsidy harvesting, which is their real purpose.

  31. It’s not just the latitude. It’s the cloud cover. There was the same problem with the USAAF when they wanted to daylight precision bomb Germany. It ain’t Arizona. Half the time you can’t see the ground. You can imagine what happen with the mirrors. Mostly you’d just have a very bright sky.

  32. SBML:

    Have they thought about the consequences of beaming sunlight to area in darkness. Think of all the environmental harm. Animals having their daily cycles disrupted would trigger any environmentalist.

    Of course they haven’t, and the solar arrays that pick up all that light are 100% efficient and will pick up all the extra energy poured in…

    Except that they don’t, and you will be heating the planet very locally for a tad more than just those 2 hours front and back, because those mirrors will be used to “Increase Efficiency” as long as they’re able to Hit The Spot. Because Incentives….

    Standard meteorology tells us what happens when an area of the planet suddenly heats up compared to the surroundings: You get thunderstorms. Big’uns.
    Possibly even tornadoes if you get enough heat and convection in.
    And that’s just the short-term effects…

    You don’t need to be an Environmentalist or a NIMBY to spot the problem with that.
    The idiots that came up with this should be taken to the back of the Shed.

  33. Did any of you see The Three Body Problem on Netflix?

    It’s boring, read the books instead, but it does at least give the viewer a sense of how bloody vast space is, and how huge an engineering challenge it would be (for humans) to accelerate even a small probe to 1% of c. That pitiful, tiny mote cast into the infinite void would cost us trillions.

    We’re not even a Type 1 civilisation on Kardashev’s scale. Not even trying to be, in fact. We’ve got scoundrels holding us back.

    In The Three Body Problem, the Alpha Centauri system sucks so much the natives decide to come here and steal our planet. They enlist the help of powerful human misanthropes, the first of whom was one of the rotten flowers of China’s disastrous Cultural Revolution. (Wow, it’s almost as if the Chinese author is trying to warn us about Something)

    If you were deliberately trying to prevent a species from becoming an interstellar spacefaring species, you’d want them to go Net Zero. If you imposed Net Zero on another country, it would be an act of war. Ya feel me?

  34. The way that the Greenhouse Effect works is that the Sun’s energy incident upon Earth is retained in the biosphere. Temperature is the amount of energy in a system. Greenhouse gases, chiefly water vapor plus some carbon dioxide and other trace gases, delay the emission of energy into space. The energy residence time is longer and temperatures are higher. Without the Greenhouse Effect, Earth would be uninhabitably cold.

    Followers of the Church of Anthropogenic Global Warming (commonly known as Climate Change), avow that carbon dioxide is the chief, major agent in delaying energy radiation into space. Suspend disbelief for a moment and assume that this is so. Get rid of carbon dioxide and energy will escape to space at exactly the right rate, not too much and not too little. You know, Goldilocks, Hosannah and water into wine.

    Now the forons want to reverse the process and pump more energy from space into the biosphere. Miraculously this increased energy will not raise temperatures in the system.

    The idea, dumbasses, according to your own religion, is to balance the radiation budget by increasing radiation out. It won’t work if you increase radiation in.

    Forons.

  35. There’s also a short story by a Chinese author about a guy from a rural village who ends up being the person who has to do the maintenance and keep the mirrors polished etc

  36. Sigh.
    The point of the Arthur C. Clarke short story was that while the army was going through their football referee-inicinerating mirror procedure, someone else, who had proposed the whole idea, was staging a coup while the army was otherwise engaged.

    Do you really think all these space mirrors are going to be aimed at solar farms, Nigel?

  37. BiS:

    I’ve also heard something about an effective maximum distance (not sure of the actual term).

    Basically you need a much larger mirror in order to focus it down to match the size of the farm, and the size blows up as you get further away.

    Admittedly, this was from an article I read decades ago about bouncing a laser off the reflector one of the Apollo missions left on the moon. This would not have been possible using non-coherent light because for basically any size emitter the spot size on the moon would have a larger diameter than the moon and you wouldn’t be able to detect the extremely small amount of light that came back. The laser they used had IIRC about a two foot spot size at the reflector.

  38. Again, slow to think of things; since we can’t edit I post again.

    The moon is not quite 11 times as far as geosynchronous orbit, compared to geosynchronous being roughly 18 times as far as low Earth orbit.

    So the comparison with bouncing stuff off the moon is not all that far off.

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