The Power in the Sky
With some expectation that these notes are being read by some in a sceptical manner, it may provoke mirth – initially – to mention that we think the most exciting area in the harvesting of natural energy is kite power, or more generally, High Altitude Wind Power, harvesting the powerful and steady winds of the troposphere. And we’re particularly excited by the work of an Italian company called Kitegen, for whom we wrote Kites on a Carousel.
It’s a very broad area which we’ll hardly touch upon here, but just run through a few of the emerging technologies in this field. Before we look at any others, a little taste of this promise of the Kitegen, before we even mention any of the other modalities of natural energy technology, because we think this is it.
Kitegen’s concepts may just be the complete solution to providing free-to-cheap, cheap-to-start-up, abundant energy anywhere, almost constantly.
The power that Kitegen brilliantly collect is high altitude wind power. This informative piece by Ugo Bardi, a professor in Physical Chemistry at the University of Florence, and associated with Kitegen, explains the field of high altitude wind:
The truly awesome power of the wind is found not at ground level but higher up, where it is far more powerful and constant. There are various projects around the world seeking to tap into this vast resource only a few hundred feet above our heads, a few hundred feet above our current wind turbines, up where the wind is really blowing. Average wind speed, and constancy, increases with height. And, the actual power held in wind increases by the square of the speed. So, if the wind 2,000 metres above is blowing three times the speed of the wind at ground level, that’s nine times the power; at four times the speed, it’s sixteen times the power.
Around the world there are now thousands of wind turbines, harvesting ground level wind, which does sort of come and go. If one of these big heavy turbine towers could be levitated just another 1,000 feet higher, the energy harvested would be eight-fold, and this would be coming almost constantly, with ever greater rewards of energy and constancy the higher the windmill could levitate. Alas, these expensive, fixed structures, each one built like a yacht, and all to catch the power of the wind at the bottom of the atmosphere, can’t be raised to where the wind really blows.
But, astonishingly, there actually are projects putting turbines in the air, there are windmills in the sky:
Makani Power, who have just been acquired by Google, have projects going on. Here’s a nice talk from Saul Griffith of Makani.
And also Sky Windpower:
Amazing picture of their FEG, Flying Electric Generator, and nice video on their site:
These are fantastic devices. And simple kites, as we know them, made of fabric, can soar around at those heights and receive enormous power, and there are plenty of people working out the best way of generating power from that.
Dutch astronaut Wubbo Ockels, at the Delft University, has been flying kites and generating useful electricity, and has come up with the concept of Laddermill.
More here and here
The Laddermill will be extended a lot more, and it makes a lovely picture, here operating from a plinth in a park, where one might normally expect a sculpture. If it’s going to be as cheap and simple as this to harvest electricity from above, things are definitely looking up.
There’s a lot of work going on in this area at Delft University.
These are just two others that we noticed in passing: Enerkite are interested in strong winds between 100-500 metres. And NTS.
We’ve only recently seen this. This looks significant from Kitenergy.
And we’ve recently seen this, and this was a big thrill to discover, because we thought we had thought of this. Making a doughnut shaped balloon and putting a windmill in the hole is the fantasy behind Saving for a Sunship, which is now a song for Altaerosenergies, founded at the Massuchusetts Institute of Technology.
So, it’s not a Sunship, it’s a BAT, a Buoyant Airborne Turbine. It’s look brilliant, and it can hauled around on the back of a truck and it keeps on generating all the while, whether airborne or not.
And, similarly, another imagined notion, something we saw a blogger imagine and the idea sounded very interesting, so we searched for such a thing and, lo and behold, someone has thought of it and worked it into a piece of engineering genius. This is Wind-it, whose windmills, or eggbeater turbines, could fit inside the hundreds of thousands of miles of existing electricity pylons.
A comment from Metropolis magazine on the Treehugger page:
Wind-it answers one of the greatest challenges to the development of wind power: where to site wind turbines. Choppin, Delon and Menard's design uses existing infrastructure - the towers and pylons that dot the more than 157,000 miles of high voltage power lines in the U.S. - to locate their turbines, which can be stacked within already sited structures. Moreover, Wind-it solves the problem of linking energy generation and electricity transmission in the same way - by co-locating them.
They don’t spoil the view any more than the view has already been spoiled. They retrofit the low to medium voltage pylons and they’re talking about generating 10kW each. Larger models generate up to a 1MW.
From the picture on this site it looks like about four pylons per mile, so about 628,000 pylons in the USA that could be retrofitted in this way. In Britain there’s 88,000 pylons, according to this petition to immediately adapt all pylons to include a turbine, and claims here that all of Britain’s energy needs would be met by the full potential of this.
Of course, Wind-It don’t really belong in a note about high altitude wind, but we’re not going to be mentioning ground level wind energy anywhere else, so we sneaked them in here.
Read more about Wind-It at wattnow:
And look at Doug Selsam’s amazing Sky Serpent, tens times the turbine, and, again, really obvious once you see it.
We can readily imagine Doug’s vision of Serpents many miles long across the sky. The idea would be much appreciated in China, maybe.
And at the very small scale, here’s an urban wind turbine that is light, cheap, simple to install, and suited to the twisty turbulent winds of a city. Ten million of these in a city would be easy to imagine and would maybe be making a GW at times between them. Of course, the imagination is running away now. But it is fair enough to imagine wind generators made anywhere with local materials; cloth sails and bamboo structures.
There are certainly many, many other ideas that have escaped our attention, time is tight. Time is tight in every way, so, clearly the most staggering promise in tropospheric energy or, indeed, any mode of natural energy harvesting comes from Kitegen. Kitegen are set to make a quantum leap in the harvesting of natural energy, taking from the vast power half a mile and beyond above.