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Astrium Hopes To Test Grabbing Solar Energy From Orbit
goldaryn writes "Word from the BBC today is that Europe's biggest space company is seeking partners to help get a satellite-based solar power trial into orbit:
'EADS Astrium says the satellite system would collect the Sun's energy and transmit it to Earth via an infrared laser, to provide electricity. Space solar power has been talked about for more than 30 years as an attractive concept because it would be 'clean, inexhaustible, and available 24 hours a day.' However, there have always been question marks over its cost, efficiency and safety. But Astrium believes the technology is close to proving its maturity.'"
It may be close to proving is viability, but there's no way anyone has any business calling this not-even-prototyped tech "mature."
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
I thought microwave transmission was the way to go, and they had worked out how to avoid accidentally frying non-target stuff on the ground.
I prefer rogues to imbeciles because they sometimes take a rest.
Ok, I know this would displace some fossil fuel energy use (that
is increasing the greenhouse effect and trapping heat on Earth.)
But beaming electromagnetic energy (infrared, microwaves, whatever)
from part of the Sun's radiation that was going to miss Earth in the
first place seems to be adding energy to the Earth (and thus eventually
adding heat to the Earth, as the organized EM energy degrades
(gets used and entropized).
Has anyone done the calculations to make sure that the GHG emission
replacement factor of this new energy (thus its reduction of heat trapping)
is more than the brand new heat it is adding to the Earth system?
Where are we going and why are we in a handbasket?
Just do the math, it doesn't work. The cost of launch utterly WIPES OUT any hope of income. Look, rockets are expensive, electricity isn't. That's all there is to it.
Want numbers? Fine:
http://matter2energy.wordpress.com/2009/06/12/space-power/
> Seems to me like you're going to have the same parasitic losses.
Some wavelengths get through clouds better. Microwaves are best. Given that it's warmer on cloudy nights due to IR reflection, the IR doesn't strike me as a good selection - perhaps there's a few holes in there they want to use.
Not that it makes a difference. For the price of the rocket you need to launch one panel, you can buy hundreds of panels. That will generate hundreds of times the power. It's an utterly stupid concept.
Maury
As with almost every other Gundam, the designs were cribbed from actual research. 0079 had the O'Neill Cylinders (with higher spin rates for dramatic effect), Wing had pairs of linked counter-rotating ring stations (artificially lit rather than using chevron mirrors, IIRC), Turn-A had a hypervelocity skyhook (and a linac boost up to it), 00 had the aforementioned solar power ring concept, as well as a slightly upsized Bernoulli Sphere station.
I've said it before and I'll say it again: orbital solar makes no economic sense. You get 4 times the power capacity for a given amount of solar panel surface area, compared to building in a desert somewhere, at a mere thousand times the cost! Maybe someday it will make sense, but not any time soon.
Now there is an exception to this: if you've got an efficient system for sending power down to a ground station then there is potential for power distribution to remote sites. The US military would love this, as it would eliminate much of the insatiable thirst for diesel in places like Afghanistan and simplify their logistics enormously. But even for this why would you want to build a big heavy satellite with huge solar panels? Just build a satellite that picks up power from a base station and beams it back down. Simpler, cheaper and more reliable.
They are completely unsafe. Even a slight failure to focus the beam would destroy a huge area of land, kill thousands of people, and cause millions in damage. This analysis is based on my highly technical computer simulation.
Well, yes and no. They are going to have SOME parasitic losses, but certainly not the same ones.
Let's assume they do this in the desert somewhere, where there are only exceptionally rare clouds in the way and parasitic losses are relatively low (both for land-based solar and orbital solar). The parasitic losses attributable to the atmosphere would be approximately the same, except that the satellite doing the actual transmission to Earth would likely be in a geosynchronous orbit exactly over the receiving target, which means you'll have minimal atmospheric interference. I'm not an atmospheric expert, but I thought there was also some benefit to having a stronger/denser beam trying to penetrate the atmosphere (tended to have lower loss than a less-coherent beam).
Add to that the fact that the actual collector (or collectors) can be in a different orbit where there is no loss of sunlight, ever, and can be positioned so that the solar panels are getting maximum solar efficiency continuously. The best of Earth-based solar arrays need some sort of motorized mechanism to keep them pointed at the Sun during the course of the day, and will get maybe 10-11 hours of decent sun and only a few hours of peak sun in a given day. You easily double, or more, your yield from such a system as opposed to building it on Earth. Solar collector arrays can be built with almost no support materials and can be made FAR larger than you could possibly do practically on Earth. And, other than a collecting station here and there, no one has to give up viable, farmable, or environmentally sensitive land.
Sure, it's going to be expensive to put the little devils in orbit, but you can build them using fewer materials, they'll run at peak capacity continuously, and no one ever complained that the Great Left-Pawed Spotted Marmaset was found only at Lagrange-2 so you'll have to stop construction.
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
The first one, and associated infrastructure, costs a fortune. However, after that, your only costs are ongoing personnel costs, O&M., and the cost of new ground stations. Because the powersat-production infrastructure remains intact in orbit.
Additionally, you don't have to use silicon or other semi-conductor photocells for power: you could set up mirror arrays to concentrate sunlight on a working fluid, to heat it, and run the resulting heated gas through turbines for power generation. Obviously, you'd need a closed-loop system for that, but with large mirror arrays, behind each would be an area completely out of sunlight, and ideal for heat sinks for cooling the gases back to fluid for re-use in the cycle. . .
The economics of payback are actually not that bad: ~20 years for capital payback, and all profit from that point on. . .
You know what I always think is kind of weird?
People have this view of big-business as being this lumbering creature trying to save a cent everywhere they possibly can. Remove safety here, cut corners there, as long as it works for five minutes after it's sold, it's good enough. And, yes, in some ways this is justified. But on the other hand, this same technique is used everywhere - everywhere - in skyscrapers, in cargo ships, in the ridiculously complicated personal computer that you are using right now to read this.
We know how to manage risk, and we know how to manage safety. We can make things exactly as safe as we want to, assuming we're willing to pay the money.
We live in a world where we combust petrochemicals inside high-precision aluminum devices to fling multi-ton metal boxes around many times faster than we can run. When we get to our destination we purchase mass-produced foodstuffs, many of which have never been inspected by humans. We go to work in megaton cages of steel and concrete, sometimes in areas where the ground itself is known to shake with deadly force, and we sit there eating our food while sitting mere feet from copper cables carrying enough electricity to kill us a hundred times over, protected only by drywall and rubber insulation.
All of these things were provided by the lowest bidder.
And then we go home and complain about the scary new lasers and how people don't make things like they used to, damn them, they'll destroy us all, if only they didn't cut corners.
I dunno. Somehow I'm just not all that worried.
Breaking Into the Industry - A development log about starting a game studio.
All your math and reasoning is sound, this proposal makes *zero* economic sense for the general civilian electricity market (most cases). But I think, from what they are shooting for as customers eventually, that this won't matter as much, the cost part. They are defense and space contractors and what they want to build is a near-virtual instant completely mobile power plant, and sell that service to governments/militaries. ex: All of a sudden they need a megawatt or three of reliable power over here behind this sand dune in east ashcanistan, they need a lot of power. they need it *today*. Try to truck or fly in the all hardware plus fuel for the whole plant, directly through "bad guy" territory, get it set up and running, or only have to have a smaller receiver station, perhaps delivered in one fast helo load? I think that's the real target and business model.
Another use would be for disaster relief, a fast big power supply at the scene. Situations like that can justify a higher cost and being highly mobile.
I was reading last month or so ago what it costs to run fuel generators in ashcanistan out in the boonies there..man..it winds up costing them something like 400 bucks a gallon to get fuel delivered. The cost is hugemongous to run those gennies in some circumstances then. This thing might actually turn out to be cheaper for extreme niche purposes like that.
Of course, on the other hand.. I don't care what they say, a huge electricity source in space, connected to a wicked powerful laser with precise aiming abilities...they can *claim* it ain't a weapon all day long...;)