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Energy from High-Altitude Kites
maddmike writes "High altitude kites could produce energy equal to some power stations at a comparable cost without polluting. The technique uses a thing dubbed a 'Laddermill' - a chain of kites attached together to create a loop in the sky more than 5 miles long."
Could this type of system withstand a strong storm system? Electrical energy, very high wind speeds...
"How does this differ from regular windmills?"
More surface area. The overall thing I'm worried about is the upcoming pollution of the airspace. Kind of what happened to outerspace.
Also what will happen if the cable snaps. They worry about the kite, what about the heavy cables falling and destroying things down here.
With these cables how are they going to fly the kite from the ground ? Will they use turbines from the military planes to blow air ?
Anyone has more information about it ?
-a
Don't worry, if it's successful it's not pollution we'll have to worry about - it'll be the fact that they absorb all the energy of the wind, mess up the climate, and then cause all sorts of weather anomalies. Instead of global warming, we'll have...global "stasis?"
why not use the kites to collect solar energy? Although, I don't know how better/worse this would be, but it could free up a lot of land needed to maintain solar panels - and depending on how high the kites are, could they could collect energy in nasty weather! With regards to aircraft, I'd say make these power-gathering areas no-fly zones -- otherwise how different is it from a field of broadcast towers?
Now then, Dmitri, you know how we've always talked about the possibility of something going wrong with the Bomb...
This means the cable is actually ten-plus miles long. I don't remember my differential equations from twenty years ago, but I do know that as the cable gets longer (goes higher), the amount of weight supported increases. So half the loop is a five mile strand going up, and the other half is five miles of cable coming down. It sure seems like the weight on the top kites would be extraordinary. Do we have carbon-fiber cable yet?
And what happens when lighting hits it? Didn't Tesla manage some stunning current with a structure less tall than this?
"The most sensible request of government we make is not, "Do something!" But "Quit it!"
I wonder about what happens if the line breaks.
Reminds me of something I saw when I was a kid. My dad and I were fishing off the coast of Cape Cod. The boat we were in was a 23' center console with twin 135hp engines. If memory serves me (this was some 25+ years ago) the boat would do about 40mph on a flat calm. Anyway... There was a good stiff breeze, good for sailing, kight flying, etc. At one point not too far in the distance we saw an orange kite flying in the sky. It was one of those $1.99 plastic things you can buy in any toy store. Well it didn't take us too long to realize that nobody was flying the kite because they'd have to be in the water given its location, and there weren't any other boats in the area. We decided to investigate (the fish weren't biting) so we headed towards the kite at full-throttle. It took us about 45 minutes but we eventually caught up with the kite. The string had apparently snapped or whoever was flying it had let go of the string. Enough string was dragging in the water to create just enough drag to keep the kite aloft, and the kite was dragging it through the water at a pretty decent speed. If the boat wasn't as fast as it was we probably wouldn't have caught the kite. We figured it could have made it all the way to Europe in a week or so if we let it. (Makes for a good story anyway) But it ended up in our closet instead.
I suppose as long as the kites in this ladder-thingy are designed properly they would continue to fly upright. But unless they have enough drag (like the string in my little tale) I'd suspect that the wind would just blow it out of the sky if the line were to break.
The numbers don't make much sense. 100 megawatts is about 75 MILLION horsepower, or about 35 BILLION pound/feet per second. It would take a HECK of a kite string, probably thicker than a suspension bridge cable, to bring down that much power. Just supporting the cable is going to take a heck of a high wind.
That's interesting... what happens above 60,000 feet, out of curiosity?
--
lds
The winds do not blow the same direction as you go higher. Sometimes you get 90 degree shear or 180 deg shear. The poor kites will always be doing a shuffle to work correctly and efficiently between the low-level, mid-level, and high-level winds. I think that this plan is how he plans to get his pies-in-the-sky......
If height is the issue, then why not have a tethered blimp hoist wind turbines? You could even cover the top of the blimp with flexible solar panels and have a high-flying hybrid system and you don't have worry about bombing people with a giant bicycle wheel if the wind died. If the weather gets bad just reel the blimp in.
Use the pancake rotor types, carbon composite blades, you could make some pretty high production turbines that were light enough to be raised by a blimp. Some kind of frame and the tether could double as the transmission cable.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
Reminds me of a short novel published in an early 60s Analog by Walt and Leigh Richmond (which may have been called "Shortstack").
A lone genius move out into an arid southwest desert and quickly bulldozes out an underground home. He then feeds one end of a roll of sheet plastic into a jig that turns it into a very long tube.
After attaching some wire our genius somehow flies the entire (mile long?) tube up into the sky like a kite, and fastens the bottom end to a rig on the ground.
The air near the earth being relatively warm rushes up the tube, stiffening it. The resulting current turns a fan blade, powering an electrical generator.
Condensation along the inside of the tube constantly trickles down and provides all the water our hero needs.
I think he gets the girl.
Several groups have been studying hanging kilometer long wires from satellites to generate energy for the satellite or space habitation. These operate on the same principle: exploit the electric field gradients in the earth's magnetosphere.
Several orbital experiments have been tried. I recall one time mechanical problems prevented full unwinding of the cable. Another time the cable shorted and burnt apart from a power surge. I suspects these bugs will be eventually fixed by the engineers.