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Solar Energy in Space is not Necessarily Easy to Harvest (Video)
The ARTEMIS Innovation web site says, "John C. Mankins, President of Artemis Innovation Management Solutions LLC, is an internationally recognized leader in space systems and technology innovation...." And one of John's biggest recent projects is coming up with a practical way to collect solar energy beyond our atmosphere and use it not only in space, but how to beam it down to the Earth's surface where we can use it to power our plug-in cars, household appliances, and other electrical devices.
I just want to point out that solar energy captured by most of these satellites would have missed the Earth otherwise.
So we would be adding extra energy to the Earth, energy which would degrade with use to, you guessed it, heat.
Has anyone done the math on this to see whether doing this would actually help in the effort to limit global warming?
I suspect that the added heat would be tiny compared to displaced fossil fuel-burning carbon emission heat-trapping, but just though someone should crunch the numbers to make sure we wouldn't be shooting ourselves in the foot with this technology.
Where are we going and why are we in a handbasket?
Or was there some sort of relevant / interesting information in the article somewhere that I somehow didn't see?
And really, we're linking peoples' linkedin profiles in article summaries now?
"Oh, goodness. Look at my wrist, I have to go." "But what about your clothes?" "I don't love these."
... and there is simply no sane way that paying a MINIMUM 32 MJ/kg to move a kg from the earth's surface to low earth orbit -- that's the minimum that assumes perfect efficiency, which is all by itself pretty funny, multiply it by maybe 100 or 1000 to get an actual estimate -- is ever, ever, ever, ever, ever going to give you a ROI compared to installing solar cells on earth at an identical cost. And then you have to extra problem of getting the energy you harvest in orbit to the ground, which either involves putting a huge receiver somewhere to pick up relatively low intensity downbeamed microwaves (at some major hit in waste heat an inefficiency) OR using less ground area but building a super-maser in orbit that can cook an entire city to extra crispy in a few minutes.
What could go wrong?
Once again, when confronted with an idea that is so very, very, very far away from economically feasible or sane, the right thing to do is club the person suggesting that they will implement it all, with our money (natch!), while keeping ownership and control of the death ray -- I mean "orbital power station" -- is to knock them down and club them with a heavy blunt instrument until they stop twitching.
The guy in the movie about actually pretty much said just that. The only thing it might make sense to lift into orbit for power is solar cells for powering SPACE devices, vehicles, living quarters, or fusion plants once we manage to build one, assuming we can make one small enough and light enough and capable of rejecting heat in a vacuum enough to be able to operate for decades on a small fuel load.
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Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
Just because something is "technically possible" does not mean it's a good idea. There are things that are *possible* technically, but impossible economically or so impractical due to size, complexity or other possible solutions exist which are not so hard/expensive that it doesn't make sense to do them. This idea of collecting energy in space, transferring it to the surface to be used is one of these ideas.
First, it's technically possible, but to do this on an industrial scale will requires HUGE systems to be build in space and on the surface. If you use microwaves to transfer the energy, the structures required are literally measured in kilometers, both in space and on the ground.
HOWEVER, it's not practical for economic reasons so it won't ever happen.
1. Throwing huge structures into orbit is pretty costly and energy intensive. Just getting the materials into orbit for a structure 1Km by 1Km is a daunting task, but then loading it up with solar panels, maneuvering devices to point both the solar arrays and transmission array is only going to add weight, complexity and expense.
2. Efficiency is going to be crap. Some folks claim 95% transfer using microwaves, but nobody is calculating the systems real losses going from solar panel output, into microwaves, transfer (at 95%), conversion back to something useful. I'd be willing to bet the attainable efficacy of this system would be below 50%, which means you have to fly twice the solar panel capacity than the energy you are going to get.
3. The ground station part is measured in Kilometers too. It's going to suck up a LOT of real estate in really large blocks to beam the energy down.
4. There are easier and cheaper ways to do the SAME thing. Oh yes, here is the BIG rub for these wide eyed nut jobs.... It's going to be more cost effective just to throw up solar panels on the surface and forego all the complexity and expense of collecting in space. Seriously less expensive for the same amount of power. It will be less expensive to initially build, it will be less expensive to maintain and I'll bet it will be more efficient. You can build this solar collector in the same (or smaller) tract of land than the Microwave collector, or spread it out into smaller tracts and avoid the expense of the legal fight necessary to put a 1Km by 1Km parcel of real estate to public use. Solar on the ground is cheaper, more cost effective and a whole lot more efficient.
My conclusion is it won't happen as much as we like the Pie in the Sky idea it is stupid one. The ROI isn't there and other viable options exist which do the same for less cost So while it's an interesting thought experiment, we need to be investing in things which have promise of being more practical if they can be made to work, things like Fusion power.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101