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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."
>> coming up with a practical way to collect solar energy beyond our atmosphere...down to the Earth's surface
That's easy! You just run an big orange extension cord down the space elevator.
Good idea. Let's spend massive amounts of energy to go to space and set up solar arrays there and beam the energy back down to earth, instead of just using the vast amounts of free and suitable area we have here down on earth to collect the massive amounts of energy already being radiated upon us by the sun. HOLY FUCKING SHEESH, ENGINEERS, GET YOUR HEADS OUT OF YOUR ARSES ALREADY.
https://matter2energy.wordpress.com/2012/03/17/the-maury-equation-redux/
John and I had an exchange after he published a similar report some time ago.
In spite of pointing out the mathematical impossibility of the concept, here he is again pushing the same pipe dream.
If you used mirrors, heat and some sort of fluid medium to run pumps and a generator, the size of the installations would be unlimited. Of course, this would require moving parts and therefore, more maintenance. The solution to that might be to make thousands of small fluid medium solar units and assume that they will eventually fail and be replaced.
Please do not read this sig. Thank you.
... 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.
rgb
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
Yep! Good enough for my neighbor Skeeter, good enough for NASA.
SJW's don't eliminate discrimination. They just expropriate it for themselves.
Nothing in space is easy to harvest. I mean, it's in fucking space. If it were easy, we'd already be doing it.
You are welcome on my lawn.
.... but wouldn't beaming the energy back down to earth kind of make collecting it in space in the first place sort of pointless?
File under 'M' for 'Manic ranting'
Maybe I'm confused, but isn't the sun's energy already beamed down to Earth? Why launch an expensive and inefficient system into space at great cost when we can just install the system right here? What you save in launch costs would pay for a lot of capacity.
Literally, the only thing left of you would be a tiny carbon footprint.
Who believes a government wouldn't use any tech for weaponry? Better yet, make us promises that the communication system to tell that orbiting death ray where to point can't ever be hacked.
What could possibly go wrong.
For opening our eyes: https://www.youtube.com/watch?v=gVgM2BlMczY
>> coming up with a practical way to collect solar energy beyond our atmosphere...down to the Earth's surface
That's easy! You just run an big orange extension cord down the space elevator.
That's actually a better idea than the "Use Microwaves and BEAM it down" junk I've argued about in the past.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Getting the energy down to earth may be another matter--which is a case for building what needs to use the energy right there in space next to the collector.
Every space based solar power plant you put in orbit will produce more energy over it's lifetime if you put it in the desert.
Even if the launch costs are zero and the transmission from space to earth is free and lossless, space based solar power is still a bad idea.
The problem is cell degradation in space is around 8 times higher, but energy production is only 6 times higher than in a desert.
But some ideas just never die.
Even Elon Musk with his rocket and solar companies, thinks its a terrible idea.
Who keeps advocating this? Beaming the energy to earth is the same thing as having a space based microwave laser pointed at the earth. You could incinerate any target you wanted on the surface of the earth with that thing.
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
"The Case for Space Solar Power", by John C. Mankins, 2014.
http://aeweb.tamu.edu/aero489/ESBI.Spring.15/the%20case%20for%20solarpower.pdf
Oh waaaaaaa. Get back to work.
Beaming energy down is only useful at night anyway. So keep it simple and put a mirror up there and the solar cells can stay on ground.