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This Satellite Could Be Beaming Solar Power Down From Space By 2025

Daniel_Stuckey writes "A NASA veteran, aerospace entrepreneur, and space-based solar power (SBSP) expert, [John] Mankins designed the world's first practical orbital solar plant. It's called the Solar Power Satellite via Arbitrarily Large PHased Array, or SPS-ALPHA for short. If all goes to plan, it could be launched as early as 2025, which is sooner than it sounds when it comes to space-based solar power timelines. Scientists have been aware of the edge the "space-down" approach holds over terrestrial panels for decades. An orbiting plant would be unaffected by weather, atmospheric filtering of light, and the sun's inconvenient habit of setting every evening. SBSP also has the potential to dramatically increase the availability of renewable energy."

15 of 245 comments (clear)

  1. My god, what has science wrought??? by kruach+aum · · Score: 5, Funny

    A satellite directly beaming solar power down from space? We've created... the moon.

    1. Re:My god, what has science wrought??? by You're+All+Wrong · · Score: 4, Funny

      The moon's too lossy, and keeps having its time of the month where it's completely useless. For getting solar power beamed down from space, I'd propose using ... the sun!

      I'm curious - how much taxpayer funding has this received? Is this just another one of the "ride the replace-fossil-fuel-usage bandwagon" schemes?

      --
      Your head of state is a corrupt weasel, I hope you're happy.
    2. Re:My god, what has science wrought??? by mcgrew · · Score: 4, Insightful

      I'm curious - how much taxpayer funding has this received?

      Less than a day's worth of military funding, I'm sure. And this is not an expenditure, it's an investment.

    3. Re:My god, what has science wrought??? by Dereck1701 · · Score: 5, Interesting

      "Less than a day's worth"

      You''re being WAY to generous, the US military spending for 2012, ignoring all of side costs (possibly as high as $500 Billion) is roughly $900 Billion dollars. Broken down to a "By Day" cost it is $2.46 Billion per day, with that kind of money you could probably finish development and put a significant amount of this concepts hardware into orbit. If any taxpayer money was used on this study it would probably be measured in seconds of military spending (~$28,500 per second) at most.

    4. Re:My god, what has science wrought??? by hedwards · · Score: 4, Insightful

      I can't help but notice that you're comparing with social programs, and the DoD, which is grossly overfunded, is thrown in as an after thought. Goes to show why the US is in such trouble. Wellfare programs are essential, but get relatively little money. But, the DoD, gets a crap load of money, with little or no benefit for the funds.

      What's more, a huge number of the people on welfare are there because we signed all those free trade agreements and shipped the decent paying jobs overseas. All while making it harder and harder for employees to organize, and slashing taxes that the rich pay.

    5. Re:My god, what has science wrought??? by number6x · · Score: 4, Informative

      The $600 Billion that you quote does not include all military spending. quite a bit of the $2.3T you list for social spending includes military pensions, the GI Bill, and the VA hospitals:

      • Government Pensions (including Military pensions) $1.0 trillion
      • Government Health Care (including VA Hospitals) + $1.2 trillion
      • Government Education (including GI Bill) + $0.9 trillion
      • National Defense + $0.9 trillion
      • Government Welfare + $0.6 trillion
      • All Other Spending + $1.6 trillion
      • Total Government Spending $6.2 trillion

      That is about $1.1 trillion more than we took in in taxes. The way our 'National Defense' spending is skewed towards big contractors and away from the soldiers, I would probably guess that there are quite a few veterans in the 'Government Welfare' figure as well.

      The 'All Other Spending' includes foreign 'Military Aid'. The majority of which goes to Israel, Afghanistan, Pakistan, Iraq and Egypt to help pay for their military budgets. Total Foreign Aid comes to about less than 1% of budget. About $14 billion in foreign military aid, $23 billion in foreign humanitarian and developmental aid and $18 billion in 'other' foreign aid.

      So there is military spending that is outside the pentagon's budget. A lot of it, for soldiers and veterans, gets included in the social spending.

  2. lol by etash · · Score: 4, Interesting

    how exactly can it "revolutionize disaster relief" when it needs an almost 40km^2 (6-8km in diameter) receiver array on the ground to get the power beamed from the satellite. Disaster relief means fast deployment. How fast can you deploy a 40km^2 grid on the ground?

    not even mentioning the fact that if you had 40km^2 of land you could just set solar panels there and do the thing for yourself with much less energy losses.

  3. Japan and the ESA are doing it too by AmiMoJo · · Score: 4, Interesting

    Japan is already working on a prototype solar power satellite. The ESA has an active project. I'd hope NASA could work with them on this one.

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  4. Nope. by Anonymous Coward · · Score: 5, Interesting

    The energy needed to put solar cells into orbit is not recouped over their lifetime outside the protecting atmosphere. Solar cells are used on spacecraft out of necessity, not because they're cost efficient.

    I know this is an unpopular view on Slashdot, where atomic energy fans come together to bash all other technologies, but solar cells work fine on the ground. You can fill the supply gaps with conventional power plants and still come out far ahead CO2-wise compared to the current power mix. Production has hardly scaled up, but solar cells are already competitive in some markets. The point of these stories about satellite solar farms is to give you the impression that there needs to be some extraordinary investment or innovation before solar power can be used. That's a lie, designed to put a drag on solar power. Solar power is ready to be used, you just have to do it.

    1. Re:Nope. by mark99 · · Score: 5, Insightful

      Agree with the poster. I figure solar cells in space will not trump solar cells on the ground until we dramatically lower the cost of delivery to orbit. At the moment we SpaceX is quoting 4300 USD/Kg to orbit on a Falcon 9 (1.1 - still waiting on maiden flight Sept5), and maybe down to 1200 UDS/Kg for the not yet built or demonstrated Falcon Heavy. And that is to LEO, Solar Cells probably need GTO which is about twice as expensive. I can't imagine a space based array can be competitive at those prices.
      Now if someone built a rail-gun based launcher, then maybe it could make sense.
      And as AC mentioned, we are in the midst of a ground based solar cell revolution right now. Very cool...

    2. Re:Nope. by Anonymous Coward · · Score: 5, Informative

      Here's some hard numbers on "traditional" approaches to solar ground vs space:
      http://physics.ucsd.edu/do-the-math/2012/03/space-based-solar-power/
      "You can even throw in batteries in the ground system without exceeding the space cost, and all the reasons for going to space have melted away."

      It would be interesting if TFA had some hard numbers to compare against in terms of generation capacity vs launch costs vs upkeep/replacement schedule... Can't find anything myself though...

    3. Re:Nope. by Lloyd_Bryant · · Score: 4, Insightful

      I think, and I'm not as smart as I once was, so this an opinion, not a statement of fact, that a geosynchronous satellite would be eclipsed by the Earth for a significant percentage of the time. There's probably an orbit that maximizes energy collection, but I don't have the slightest idea what it looks like.

      Not all that significant. Remember that the Earth's equator is inclined about 23 degrees relative to the plane of the ecliptic. Because of this tilt, combined with the distance the satelleite is from the Earth, a solar power satellite will experience *no* eclipses from the Earth for about two thirds of the year, and some period of eclipse during the remaining third. But even at the worst point in the cycle, the eclipse period is only about 70 minutes per day.

      Net result is that a good old geosynchronous orbit is good enough for a solar power satellite (and greatly reduces the headaches of keeping the power beam targeted at the receiver).

      --
      Don't tell me to get a life. I had one once. It sucked.
  5. Re:Control API Security by Kell+Bengal · · Score: 5, Funny

    would someone please at least a security engineer before they design the control API for the thing?

    No. There's no pleasing security engineers.

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  6. Re:So why not...? by Culture20 · · Score: 4, Informative

    Because solar orbit at 10% earth distance would make the magnifying glass zoom around the sun multiple times per earth year. There would be no way to get the rays from the glass to the collector. You'd be better off having the collector out there with an amiable maser.

  7. Re:It's a cover by ColdWetDog · · Score: 4, Funny

    Yeah, we're more of a Kardashian Type ''civilization' now.

    We're doomed.

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