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China Earth Power Space Technology

Chinese Scientists Plan Solar Power Station In Space 226

knwny points out this lofty proposed power plan in China. "The battle to dispel smog, cut greenhouse gases and solve the energy crisis is moving to space. If news reports are to be believed, Chinese scientists are mulling the construction of a solar power station in a geosynchronous orbit 36,000 kilometres above ground. The electricity generated would be converted to microwaves or lasers and transmitted to a collector on Earth. If realized, it will surpass the scale of the Apollo project and the International Space Station and be the largest-ever space project."
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Chinese Scientists Plan Solar Power Station In Space

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  • No they don't (Score:5, Informative)

    by Maury Markowitz ( 452832 ) on Monday March 30, 2015 @07:55AM (#49369643) Homepage

    This stupid idea gets floated every few years. It doesn't work, even in theory. Do the math yourself.

    https://matter2energy.wordpress.com/2012/03/17/the-maury-equation-redux/

    • by gTsiros ( 205624 )

      and it will get floated every couple of years until they figure out how to make it worthwhile

    • Re:No they don't (Score:4, Insightful)

      by PolygamousRanchKid ( 1290638 ) on Monday March 30, 2015 @08:12AM (#49369769)

      transmitted to a collector on Earth

      . . . or fry Washington, DC or Moscow . . .

      Take a look at "Diamonds Are Forever" for all the details.

      • by cbelt3 ( 741637 )

        Since anti satellite technology is quite mature and tested, anyone who thinks that such a system would not have the equivalent of a few dozen nuclear shotguns permanently parked near it is... clueless. Of course the effect of having to destroy that would effectively make Earth orbit a no-go zone for decades until someone started sending up sweeper robots.

    • by Mr D from 63 ( 3395377 ) on Monday March 30, 2015 @08:18AM (#49369821)
      Talking about something and planning it are two different things. It appears whoever submitted this article fabricated the idea that this is being 'planned', or maybe its a problem with reading comprehension. It is clearly not being planned.
    • by OzPeter ( 195038 )

      This stupid idea gets floated every few years. It doesn't work, even in theory. Do the math yourself.

      https://matter2energy.wordpress.com/2012/03/17/the-maury-equation-redux/

      I just took a look at that site, and while in general I agree with his conclusions, I am perplexed by some of the math that he uses.

      For example I do not see why Tg is different for ground based versus space based systems, and why it so not eliminated as per the E term (and why is Tg higher for a space based system?). And the links he supplied for the lifetime of space based cells are frankly puzzling to me as I cannot see anything in them that backs up his assertions (which is different from saying his ass

      • by itzly ( 3699663 )

        he leaves out the fact that a space based PV system operates 24/7 with continuous output compared to an earth based system that has to deal with the vagaries of weather and that pesky thing called "night".

        Isn't that represented by the higher "I" factor for space based cells ?

      • by OzPeter ( 195038 )

        Given that I am not a rocket scientist I just realized that I made an assumption about satellites in geosync orbits - that I don't know if the inclination of the earth is such that a satellite in a geosync orbit is always in sunlight.

      • > For example I do not see why Tg is different for ground based versus space based systems

        The reason should have been explained, which I now realize has not been. Basically it *should* be easier to convert constant "insolation" from the rectenna to AC power than doing the same for variable inputs from the PV panels.

        But you know what, you're absolutely right. It has basically no effect on the outcome, and simply confuses matters. I'll update the article and leave a note at the bottom.

        Actually I should do

        • Hi Maury,

          * Spectrolab rates their space solar panels for 20 years at GEO: http://www.spectrolab.com/Data... [spectrolab.com]. Since they don't need to withstand weather, they can be much lighter than ground-mounted panels. 13 W/kg for a typical ground panel (not counting mounting and tracker) vs 177 W/kg for the space ones. That has implications for the energy payback time if you manufacture the panels in space.

          * Your comparison of operating hours neglects that in space you have 36% higher insolation, because there is no

          • > Spectrolab rates their space solar panels for 20 years at GEO

            This is not the 20% degradation point I use in my article, this is the "totally dead" point. The "totally dead" point for the average solar panel on earth is unknown, because they haven't been in service long enough to know. All we know for sure is that the vast majority of panels installed in 1982 are still working just fine today (and I know examples from the 1970s). Some have suggested the totally dead point for panels on the ground is at

      • I just took a look at that site, and while in general I agree with his conclusions, I am perplexed by some of the math that he uses.

        I don't necessarily agree with his conclusions, but agree that some of his math is...perplexing.

        For instance, he gives a ground-bases system a lifetime of 40 years, but a space-based system a lifetime of only 12 years. Off the top of my head, I can't see any particularly good reason why a space-based system should be shorter-lived than a ground-based system.

        If, instead, he'd

        • by itzly ( 3699663 )

          I can't see any particularly good reason why a space-based system should be shorter-lived than a ground-based system.

          Radiation. Damage by micrometeorites.

          • Since the space based system isn't exposed to regular moisture or oxidation though I'd bet most of it would actually last longer rather than less. The exception being the electronics package due to the aforementioned radiation, though that should be something you could deal with by putting in some redundancy, hardening and shielding. (obviously at some cost though the area protected wouldn't be particularly large).
            • by itzly ( 3699663 )

              Since the space based system isn't exposed to regular moisture or oxidation though I'd bet most of it would actually last longer rather than less.

              It's subject to radiation, such as electrons and protons. If these hit the panel with enough energy, they will knock out silicon atoms, creating defects in the crystalline structure. Over time, this will cause the power output to drop.

        • > Off the top of my head, I can't see any particularly good reason why a space-based
          > system should be shorter-lived than a ground-based system.

          The reasons are very clearly explained right there and I even linked to the real-world articles I took the numbers from.

          >he 'd assumed a similar lifetime for the space-based system

          Look at the image at the top of the page. Do you see it? That's Mir's solar panels after about *10 years*. Hubble replaced its panels twice over a period of 13 years. Space absolu

    • Re:No they don't (Score:5, Interesting)

      by AmiMoJo ( 196126 ) * <mojoNO@SPAMworld3.net> on Monday March 30, 2015 @08:50AM (#49370035) Homepage

      JAXA (the Japanese space agency) has done the maths and decided it will definitely work. They describe the system in detail here: http://spectrum.ieee.org/green... [ieee.org]

      JAXA intends to test the technology in 2018.

      • Re:No they don't (Score:5, Interesting)

        by Maury Markowitz ( 452832 ) on Monday March 30, 2015 @08:57AM (#49370079) Homepage

        > JAXA intends to test the technology in 2018

        No, they don't. The project died, if it ever existed in any meaningful form, because it never had a budget.

        It was a trial balloon sent up by the space industry to create demand for new rockets. That's the only reason this idea keeps getting floated, as an excuse to make more rockets or heavy launchers.

        • ofc it had no budget.

          (*facepalm*)

          That does not change the fact that the math is pretty solid and it would work.

          The problem is to build such a solar station in orbit, not to fund it, or to make a profit from it.

          Or how exactly would YOU assemble a structure 100x100 meters or even 2x2 km in square in GEO?

          Why do you seek problems where are none and are so blind to see the obvious obstacles?

          • Or how exactly would YOU assemble a structure 100x100 meters or even 2x2 km in square in GEO?

            Create a modular design and use remotely operated drones to assemble it.

          • > ofc it had no budget.

            Then they couldn't be intending "to test the technology in 2018", could they? You need *actual money* to build *actual hardware*.

            It was a trial balloon, precisely like this one. Free press for a slow news day.

            > That does not change the fact that the math is pretty solid and it would work.

            Go right ahead and demonstrate the math in question. Develop from the CAPEX side through to the LCoE. Include OPEX and regulatory loads, if you care to.

            Or you could save yourself the trouble and

        • by AmiMoJo ( 196126 ) *

          It's still a current project:

          http://www.ard.jaxa.jp/researc... [ard.jaxa.jp]
          http://www8.cao.go.jp/space/pl... [cao.go.jp]

          They are exhibited it recently: http://global.jaxa.jp/area/ssp... [global.jaxa.jp]

          They took a major step forwards with the technology only weeks ago: http://phys.org/news/2015-03-j... [phys.org]

      • NASA, JAXA and similar outfit drool at the perspective to have a long term project where they need to send a lot of cargo up, means a lot of contract and assured budget.

        Those folk tells the space solar collector are possible and desirable.

        The folk at energy production on the other hand use a calculator for cost of setting up, maintaining compared to generated energy and they usually view that as possible but not profitable compared to a similarly sized (in megawatt) installation on earth with physic

    • The analysis seems to miss an important point about the difference of space- zero gravity. I am in the southwest and there are several solar installations in our area and the panels are mounted on some pretty elaborate framework. I wouldn't be surprised if the support structures rival the cost of the actual panels.

      In space you could use extremely thin panels with little or no support.

      • by itzly ( 3699663 )

        In space you could use extremely thin panels with little or no support.

        Except that in geostationary orbit they would have to be tracking the sun, while the downlink needs to stay focused on the ground station. So, they still need some rigidity.

        • You can envision something with an umbrella or sail like structure with carbon fiber supports. Perhaps the panels would be actually manufactured in zero-g and take advantage of novel properties of crystal growth in this environment.
          The point is the actual structures would not resemble anything we have on earth.

      • I presume that the panel systems you stare at were not launched out of a deep gravity well.... Satellites need to be both robust and light weight. And simple. And redundant. And cost effective.

        It's rocket science! It ain't easy.

    • Wow, someone made a stupid blog and you use it as evidence?

      If I shoot a 1kW solar "thingy" into space it can produce power like 22 - 23 hours, minimum, per day.

      Not sure how good the orbit can be for a random place on earth.

      Afterwards you only need to beam it down, the math is a no brainer.

      The question is launch costs and what the delievered energy might cost in the end.

      • by itzly ( 3699663 )

        Wow, someone made a stupid blog and you use it as evidence?

        It's his own blog. But it doesn't matter who wrote it, as you can easily verify the math.

    • More likely it's an excuse to have an orbital weapons platform or massive surveillance platform.
    • You're making two assumptions that, I would submit, undermine your argument to some extent.

      The first one is no technological progress - and with it, a corrolary that the only PV tech worth pursuing is the one working at ground level, protected by a thick atmosphere. I would expect a trade-off between conversion efficiency and lifetime to be the tech play to follow for space PV pannels - meaning different materials, different ideas that would perhaps not be economical at ground level. The constraints are dif

    • Hmmm, makes no sense as a means of generating electricity. But what can a government do with gigawatt masers in orbit, hmmmm...

      Makes great sense if one wishes to rule the world. Thus spake Brainithustra.

      rgb

  • That is quite surprising, because China is one of the world's biggest manufacturers of solar panels, and has a lot of open area with a lot of sunshine. An much easier and much cheaper solution seems to be at hand. This makes me think that the orbital city-zappe... uh... I mean... solar power plant is not entirely what it appears to be.
  • This interesting idea and technological endeavor was proposed in the 1960s maybe it was also proposed before, but that is were I read first about it - in a book from the 1960s. Later they did not build it because it was so incredible expensive to get all the materials up, repair it in space, and keep its focus on the same spot on the ground. Next, they will figure out that placing panels on roofs is much more efficient even though it will not work in their metropolises as the air is too polluted. Anyway, th

  • Either this system is implemented and a new era of clean, renewable energy from our single star is to be realized from the heart of the orient, or, takeaway from xishuangbanna goes from 15 minutes to 2 for the crispy pork belly.
  • Sim City (Score:4, Informative)

    by Bradmont ( 513167 ) on Monday March 30, 2015 @08:05AM (#49369717)
    I remember doing this in SimCity 2000. The downside was that every once in a while the sattelite would stray from its intended target and vapoirse some random building near the receiver....
    • Which makes it a nifty dual-purpose device; it provides power to your cities during peace, and fries your enemies during wartime. It's win-win!

      Get enough of 'em up there, and you can start using the satellites as solar shades too, blocking sunlight - in a very Burnsian [wikia.com] fashion - from whomever does not pay.

      Too bad the inefficiencies of microwave transmission make the whole thing a pipe-dream. Might work when we have a space-elevator that can double as an extra-long extension cord but I'm not holding my breat

    • by chihowa ( 366380 )

      Building there was a zoning violation anyway. Think of it as random and overwhelming enforcement of municipal ordinances!

      On a serious note, simply having the transmitting electronics powered by a coaxial beam from the receiver (that is itself initially powered by a low power pilot beam from the satellite) seems like it would be an effective interlock to prevent a wandering beam.

      From what I've seen, though, it's difficult to make a very tightly focused beam that doesn't lose much of its power to the atmosphe

    • We solved that problem early in the Solar Power Satellite studies at Boeing. The microwave transmitter in orbit is a phased array. The reference signal to adjust the phase is a transmitter in the center of the rectenna on the ground, powered by the rectenna. If the beam wanders off target, no reference signal, and the beam is no longer focused.

  • That's equivalent to 12 of Beijing's Tian'anmen Square, the largest public square in the world, or nearly two New York Central Parks.

    How many football fields is that? (American football). I hope when the specs are released for this space station, the length is reported in Library of Congresses so i can understand it.

    • 5 to 6 square kilometers. Or 125 to 150 square furlong, in equestrian racing units, or 45 to 54 square kilofoot, in freedom units.
  • Is it getting a little warm in here?

  • 1. China lacks a lot of knowledge when it comes to building and maintaining large things in space...
    2. Imagine China could get this to work, there's so much lost in the down link due to the atmosphere you'd need a REALLY powerful microwave emitter or laser, at which point you've now got a death ray in orbit. There are pretty strict rules about NOT militarizing space and nobody would be cool with a country having their own personal death star in orbit.
    3. If instead they decided to use low power, the collect
  • by MrSteveSD ( 801820 )
    Even if a solar panel in Geosynchronous orbit generated 100x more energy than an equivalent panel on earth (which seems unlikely), it makes no economic sense to put it there since you could put several hundred panels on the Earth's surface for a small fraction of the cost. In fact you could fill an entire football field full of panels for a fraction of the cost of the space based solution. Just through sheer numbers they would generate more than the space-based panel even on a cloudy day.

    Simple repairs a
  • by Applehu Akbar ( 2968043 ) on Monday March 30, 2015 @09:34AM (#49370331)

    When your government is full of engineers, not lawyers, and when you can just ignore the flat-earth lobby instead of wasting half your funding fighting their just-because-we-can delays, you can test ideas like this. If it can be made to work, it would mean baseload solar.

    The biggest unknown is the microwave link to send power to Earth. Would locating the receiving antenna ("rectenna") array in the desert avoid weather interference? Would the beam wander? I don't see it as being usable as a weapon because a huge structure in space is easily disabled from the ground.

    The next-biggest unknown is availability of construction materials. After the initial proof of concept, lugging large amounts is metals up the terrestrial gravity well is not goiong to be an option. This is an application for "local" metals, from the Moon or from the Belt. Implementation would have to wait until this supply becomes available.

    • "The next-biggest unknown"

      But it's been pretty well known since Einstein's time that powerful energy sources also make for powerful weapons.

    • > The biggest unknown is the microwave link to send power to Earth.

      We actually have tons of data about this, from all the GEO communications satellites, and rain fade that happens sometimes.

      > The next-biggest unknown is availability of construction materials.

      I was one of the people who worked on this issue while at Boeing. We found that 98% of the materials for a solar power satellite can be obtained from the Moon. A higher percentage are available if you use the Moon + Near Earth Asteroids. We did

    • When your government is full of engineers, not lawyers, and when you can just ignore the flat-earth lobby instead of wasting half your funding fighting their just-because-we-can delays, you can test ideas like this.

      Also useful: when your government is full of unelected bureaucrats who aren't held accountable by voters, completely dominate the news media, and stomp on any popular organization or sentiment that they don't control, and thus are free to ignore the interests of their citizens and instead spend m

  • by rlp ( 11898 )

    Design it as an enormous spherical object covered with solar panels and a large antenna to beam power. And a thermal port ...

  • Space debris (Score:4, Interesting)

    by Misagon ( 1135 ) on Monday March 30, 2015 @09:56AM (#49370497)

    I think a large problem is going to be space debris - debris from previous launches and defunct satellites.
    When the idea of an orbital power station was first formed in the early days of space exploration, space debris was not a problem. These days there is a huge number of tiny objects circling the Earth at high speeds - like bullets being shot at random.
    The larger the orbital mirrors are, the more surface area there would be for collecting space debris.

    Sure, you could place them in higher orbit, but then the mirrors would not get as much protection from solar wind from the Earth's magnetic field.

    • But is this the case in geosynchronous orbit?

      • by stooo ( 2202012 )

        "The two main debris fields are the ring of objects in GEO and the cloud of objects in low Earth orbit (LEO)"

        it's not a problem of the same magnitude than LEO, but it will become one once you put up "square kilometers arrays of photocells or mylar reflectors". These things will just disintegrate at the smallest impact, and create a large debris cloud. This is why orbital mylar baloons are obsolete since long.

    • > I think a large problem is going to be space debris -

      Nope. If you can build giant solar arrays in GEO, you can build small ones and attach ion thrusters to them. See the Dawn mission at Ceres and the Asteroid Redirect Mission NASA is proposing for examples. These space tugs can putter around and collect loose space debris. That however does not eliminate natural meteoroids. So your power satellite will need a maintenance program, or just accept a small amount of degradation as stuff hits it.

      Solar

  • by cyberchondriac ( 456626 ) on Monday March 30, 2015 @11:48AM (#49371701) Journal
    I suggest stopping the moon in it's orbit and making it geosynchronous, then spray painting it with a highly reflective silver paint. That way we can get enough sunlight at night to compensate with ground-based solar panels.
    That's really simple to do, right? Easy Peasy!
    :-D
  • Don't miss the dish

  • they're contemplating building a moat around the White House.

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