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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."
One strong gust of wind and the earth could start spinning the other way.
The article doesn't say much about how such a structure could be maintained. How in the world could kites stay up for a long enough period to be feasible as a power source? Or is all this still in the "just five more years" phase?
I'd like learn more, but the article is not very helpful.
What if the entire Universe were a chrooted environment with everything symlinked from the host?
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?"
Flying kites at high altitude isn't as easy as it seem: pretty soon you get a lot of problem from the line(s), chiefly the weight of the line, but also line drag.
The former problem is essentially a strength vs. weight problem that even high tensile lines made of dyneema won't solve easily (above 400/500m, a 6m parafoil can very well sit there and refuse to climb with standard lines).
The latter problem introduces a problem of angle, since the line becomes curved under the wind drag, which makes the section right under the kite more and more vertical as it climbs, which in turn "flattens" its incidence angle and reduces its lift. It's always possible to modify the incidence on the ground to compensate, but takeoff can get dicey then. And of course, the wind drag on the line also tends to pull the kite down, and it's not negligible with a lot of line up.
So yes, it should be possible to use kites to generate power, but there will have to be a great deal of electronic magic to regulate everything, down on the ground and up in the air, if high altitude flying is to be more than stunts performed by enthusiasts on good days with (semi-)controlled conditions.
What they were saying was equal was the cost, not the total output per kite.
Mathematics is made of 50 percent formulas, 50 percent proofs, and 50 percent imagination.
Kite trains, or stacks, readily soar to heights greater than what can be attained with a single kite.
The record, set back in 1969, is 10,830 m abg. So the 30,000 ft mark has already been surpassed.
The single kite record stands at around 13K feet.
that's called free extra power
moox. for a new generation.
...took the US a little too serously when we told them to go fly a kite.
(ducking)
"Oh drat these computers, they're so naughty and so complex, I could pinch them." --Marvin the Martian
Have a look at some of the plans and protoype pics of this behemoth, and it becomes clear (if not in the article) that the intention is for the ladder to be ground-originated, not just ground-anchored. This means the kites are travelling up from the ground to 5 miles and back again. The volume occupied by such a structure - especially one as non-static as this - would be monumental, not to mention the massive safety margin required to have more than one in operation within a few miles of any other ladder.
So if we're looking at 400 ladders to generate enough to power a city, we're look at a good 3000+ square miles of land if we're to be sure that no ladder is to collide with another. Not practical on any scale, I suspect.
Now if we're to be sure the things don't come down every time there's a spot of bad weather, we are looking at getting them up above the common cloud-cover atmospheric strata. In that case, why the hell not just use bigger kites, no ridiculous ladder-arrangement, and use the kite-wing surface-area to convert solar-energy? If the kites are well-engineered and -controlled enough to be able to operate in such a stringently unified fashion, I'm sure the same technology could be used to keep solar-kites in the air. True, the strain on the cables would be even greater if they have to be reliable electrical conduits as well, but that's really only one of several major flaws in this project.
Frankly, we'd be better off burning drug-addled research-scientists as fuel. They're renewable, at least.
Meta will eat itself
This is a really interesting concept. The designers say they won't fly the kite except in good weather so they won't have to worry about electrical storms etc. but I wonder if they have considered the atmosphere's natural electric field as well... It is estimated that the natural electric field potential between the earth's surface and the ionosphere is in the hundreds of thousands of volts range. While the current is usually very low for small but rather tall structures (regular kites, radio towers etc.) I would imagine that having a huge 5 mile wide kite 30 thousand!! feet up would make an immense difference in the current transmitted through a conducting wire to the ground. We may be talking about tens or perhaps even hundreds (??) of watts here. This will have to be dealt with and I imagine it could actually be used to perhaps, power some backup or secondary control equipment way up there.
- "Hear that?! The percolations are imminent! Cease your ingress!"
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 idea of tethered high altitude wind power generation has been around for a long time. The people behind Sky Wind Power Corporation (http://skywindpower.com) have been developing their technology since 1979.
They do not use kites but a tethered electrical generator, like a helicopter with 2 fifteen foot rotors and no cabin. The documentation on their site seems to cover a lot of questions that would come up here, especially about the tether etc.
It is just sad to see another australian inventor having to go overseas to try and get their idea noticed.
You miss something, young teenager shaking in righteous angst...
The industrial world has a vested interest in maintaining itself and not destroying itself or us: If there is no civilization or people to buy goods and services, then money and soon power (as in power of the people, not nuclear power) go bye-bye.
It's simplistic and misses all those pesky nuances, but true.
Now, whether or not the industrial world _knows_ how to maintain itself and not destroy us... THAT's another question...
Humorless sig goes here.
Look at the math.
A person can generate about 1/4 horsepower with an excersize bike. Given the daily rate for unskilled labor in many countries now, we could simply rig up a giant wheel like what Conan the Barbarian pushed around as a slave in that clearly prophetic movie.
Given the cost of building a nuke plant, then running it, getting rid of the waste, (hiding it really well for a really long time), and cleaning up after it -- it would be cheaper per kilowatt to simply have a bunch of low paid people push giant logs around in a circle.
The economics are outstanding. Its great excersize, and the power companies would be incented to provide health care at the same time. It provides plenty of jobs for unskilled labor, and could quickly be set up in the lowest income countries.
All in all, its a win-win. Best of all, it doesn't suffer from the one drawback everyone is clearly afraid to speak about with wind-power, which is the potential for slowing down the rotation of the earth! Clearly a danger if ever there was one. Why, if we slowed down the earth, and there was no centrifugal force apposing the gravity of our planet we would all be crushed! Oh the horror.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
I remember when wind farms started generating controversy - mainly by those bothered by sight of them (see Kennedy's and the Nantucket Sound controversy). Those type of folks have paid obscene amounts of money to stop things like the Cape Wind project. Their reasoning (besides ruining their view of the sound in the morning)? It kills birds, it might change the climate, etc. Yeah... And what about the two coal plants that currently provide them electricity? In comparison, what do THEY generate?!
So when I see possible energy solutions like this one, it makes me rack my brains to think what excuse will these NiMBY folks use THIS time? Thanks so much for 'global stasis'. I can see the lawsuits now...
I vote for moving the coal plants in CT that feed Nantucket down near the Kennedy Compound. You might as well get them closer to where the HOT AIR is generated...
"...Well, there's egg and bacon; egg sausage and bacon; egg and spam; egg bacon and spam; egg bacon sausage and spam..."