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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."
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...
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.
Free Martian Whores!
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.
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.