Kite-driven generators have been suggested as one method of capturing this energy. In principle, they work by using the strong pull of the wind to drive a land-based turbine, tethered to the kite via a cable.
Credit: Sky Windpower Corporation
"This approach has the advantage that the heavy generator stays on the ground" said Pavel Trivailo, an aerospace engineer from the Royal Melbourne Institute of Technology, in Australia. He said he has recently applied for funding to develop Ockels' technology further, using radio-controlled gliders.
Like kites, gliders would only be useful on their way out into the wind – whilst winding back in, no electricity is generated. Trivailo imagines paired systems of kites, where one travels out as the other returns, likening the system to the paired action of a piston engine.
Gaps in the grid
He points out that cables capable of safely coping with large forces - such as those generated by wind - already exist, thanks to the 'space tethers' used to join sections of satellites.
Some challenges of high-altitude wind power are still to be met, however. "While there is enough energy in these high altitude winds to power all of modern civilisation, at any specific location there are still times when the winds do not blow," said Caldeira.
The study predicts wind may still fail about 5% of the time. "This means that you either need back-up power, massive amounts of energy storage, or a continental or even global scale electricity grid to assure power availability," he said.
Trivailo agrees much work needs to be done. "How you deploy the gliders or kites at high altitudes is still an open question," he said.
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flying a kite !!
A fantastic idea,please don't let the politicians any where near it.
Insurance
When (not if) these kite power-generators fall, they can hit anywhere (hospitals, major highways, chemical plants, etc.) and so the potential liability to their manufacturers/operators is unlimited. No insurer would write a policy under that condition and companies can't operate uninsured. Kite-power companies will need national legislation to artificially limit their liability, as now exists in the U.S. for nuclear power plants. I don't see such legislation happening while existing power and fuel companies can lobby to prevent it.
Flying kites
A little experience in Vietnam where a barrage balloon was used to hold a radio set aloft indicates that a 5000 cu ft helium filled balloon was needed to hold the back-pack radio together with its tethering cable and a radio transmission cable - and that was only to 1000 metres height.
Can anyone tell me how much the cable would weigh for these very much larger flying kites? Think in kilo-tonnes.
Yes great idea; keep 'em coming!
Funny how we are all so skeptical about politians; will we ever get them to be serious about energy and being sensible about the Earth running out of limited resources? Capitalism does not work in the long term. The man in the street sees it but our short-sighted "leaders" trundle on with their old ideas. Patting each other on the back, dreaming they are being of use...I long for sense, but I can't see any real changes coming, unless, and this is ironic, it comes from the U.S.?
Let's Go Fly A Kite...
With a decent sky-hook pulley system, we could even generate power on the downwards trajectory (if only...).
But seriously, this is only the beginning of a potentially very exciting alternative source of energy. Kites could be tethered to each other to create massive 3-dimensional high-altitude lattices of wind energy generation, to avoid the necessity of having one massive cable for every kite.
As for the risk of failure, it is actually very, very low. It is easy to imagine that such kites would have few if any moving parts. Besides, devices exist to allow things to fall safely through the air without damaging themselves or others when they land in case of emergency - they're called parachutes.
This technology is exciting and entirely feasible.
yeah
Next, we'll show how to reconcile the chinese and the russians, how to split an atom, and how to irrigate vast areas of the sahara desert.