Concentrated Solar Power 12 Miles above the Earth

[Mike90250]

http://www.theoildrum.com/node/8323

Excerpt:
Sunlight for electricity production would be concentrated at 20,000 meters (12.4 miles), and come down to the surface in a hollow light pipe tethered to the ground. The light would be converted to heat at the ground, and used to drive combined cycle turbines to make electricity. They can be located almost anywhere, even places with lots of clouds. The volunteer research is being done at a company called StratoSolar.

While most of this post is about concentrated solar power (CSP) systems, the idea of using solar PV panels at 20 km is also being considered. A section at the end is devoted to the solar PV panel approach.

[Sunking]

And just how would they keep it up there. FAA I am sure would have a huge problem with it.

Being a private pilot I can tell you the claim of calm winds at those altitudes is fantasy unless you call 100 to 150 Mph constant wind speed calm. It is called the jet stream.

[john p]

And just how would they keep it up there.5000 tons of hydrogen IN BIG PLASTIC BAGS and the thing is teathered to the ground with aq steel cable 16 inches DIA.
There does seem to be a few engineering problems.. ie the 2 klm reflector.

[Sunking]

There does seem to be a few engineering problems.. ie the 2 klm reflector.

That and minus 60 to 100 F temps at that altitude. Plastic doesn't react to will well to those temps and 100 mph wind beating it around.

Make a nice target for sabatoge, just one shot from an incendiary round. Would make one heck of a fire ball and break out windows for hundreds of mile around. I think it would make the new Father Of All Bombs that would make the Russians jealous who now have the ownership of largest conventional bombs.

[john p]

HEY mabe thats the idea.. you build it then if you dont like some dictator somewhere you "accidently" let the baloons break away then when its over the place you dont like then you shoot it and blow it up.. Then say "sorry" just trying to protect you from it getting in your air space..

[Mike90250]

In the report, they admit airplanes are a big problem.

"mid altitude" (20k-40k feet) winds are a problem, and occasional winds at 12 miles, they devised a "Dump and Furl" for the gasbag, then they re-inflate

double layer envelope on the gasbag, with a 1 meter nitrogen screening layer to keep the O2 out, and when someone has artillery shells that can go UP 12 miles, or hit a wiggly 16" rope, I'll get worried. and 12 miles up, you'd never hear the boom.


Yes, there are "hurdles" but there were problems the first years getting wooden water wheels to work too.

[axis11]

If the nutheads could hit the twin towers in 9/11, this 2km wide balloon would be an easier target!

[john p]

This figure is not 100% accurate but its close..
12miles of steel wire cable 16in in dia. weighs about 21,542 US tons. THATS A LOT OF STEEL TO SUPPORT WITH PLASTIC BAGS OF HELIUM???

[Mike90250]

This figure is not 100% accurate but its close..
12miles of steel wire cable 16in in dia. weighs about 21,542 US tons. THATS A LOT OF STEEL TO SUPPORT WITH PLASTIC BAGS OF HELIUM???

That's why they need HYDROGEN (there is not enough helium to fill the balloons)

12 miles up is 63,000 feet, not many planes can get up there, and at 40,000 feet/ 500mph, you can't see the cable till you pass it. Planes hitting a block wide building at 250mph was feasible.

I'm not going to correct folks who didn't read the article. Sorry I started the thread.

[Sunking]

12 miles up is 63,000 feet, not many planes can get up there, and at 40,000 feet/ 500mph, you can't see the cable till you pass it.

A plane would never see it or even fell it. One minute you are flying, then next you are talking to Peter at the golden gate.

[john p]

I did read it sorry i not correct with the hydrogen, but I also thought at 12 miles there aint gunna be any planes up that high to be a problem..
It was interesting story,, so it good you put in on as a thread..

[Naptown]

As far as aircraft go there are mechanisms in place to prevent a collision. Dereck you are aware of TFR's which could be set up around the cable areas on a more permanent basis. Now this does not take onto account those flying a VFR but many modern aircraft use the XM system for weather etc and the area around a cable could be charted. And no I did not read the article.

[john p]

Its ok Naptown.. I think planes running into it and having a wing cut off is the least of the problems.I think the 3 bigest problems are (1) making a 1.2 mile long reflector. (2) getting enough hydrogen to stay in all the plastic bags to hold everything up (3) hanging a 21.000 + ton cable so it doesnt wander to far from vertical.

I personally think it be cheaper and a damn site easier to build a man made island in international waters and run some cables to a country. Apart from terrorists atacking it its a safe place to have one . But of course you would need signed agreements from any whales or dolphins that lived nearby.

[Naptown]

Its ok Naptown.. I think planes running into it and having a wing cut off is the least of the problems.I think the 3 bigest problems are (1) making a 1.2 mile long reflector. (2) getting enough hydrogen to stay in all the plastic bags to hold everything up (3) hanging a 21.000 + ton cable so it doesnt wander to far from vertical.

I personally think it be cheaper and a damn site easier to build a man made island in international waters and run some cables to a country. Apart from terrorists atacking it its a safe place to have one . But of course you would need signed agreements from any whales or dolphins that lived nearby.

Just countering the aircraft objection. Engineering the thing is a whole different dream (nightmare)

[Sunking]

Dereck you are aware of TFR's which could be set up around the cable areas on a more permanent basis.

That is an oxymoron The T in TFR is Temporary Flight Restrictions. FAA only issues those in emergencies like wildfires or crash sites.