Kite Power Harnesses Unspooling Motion For Energy

October 18th, 2009 by Susan Kraemer

Here’s a radical perspective change for wind power. Instead of harnessing wind power to turn blades tethered to a pole, the KiteGen simply harnesses that rapid unspooling motion of kites reeling out as they release upwards.

So instead of a heavy static structure this is simply a light and flexible kite.

The KiteGen would hover at 2,600 feet to produce power each time the kite’s tether unspools, spinning an alternator that generates the power. When the cables are completely unwound the production phase ends, the cables are reeled in to start another production phase. The cycle repeats; like in a yo-yo in reverse.

So the KiteGen splits the components of wind power. In the air; nothing but high efficiency air foils. On the ground, all the heavy machinery for power generation. Connecting the two; high resistance lines transmitting the traction of the kite.

As this picture illustrates; the idea is to eliminate everything non essential. Only keep the most efficient part: the wing tips (drawn in red) where the action happens. Only the essentials remain, the high speed wings are separated from the generator which is on the ground. The resulting structure, base foundation included, is much lighter and cheaper.

The company holds more than 20 international patents and plans a demo by the end of 2010. These guys are thinking out of the box. They point out that there is about a GW of wind potential in the unusable no-fly air space around nuclear power plants. They suggest that’s the perfect spot for their 2,600 foot kite.

Source: KiteGen via Popular Science

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Tags: kite wind power, KiteGen

About the Author

Susan Kraemer writes at CleanTechnica, CSP-Today, PV-Insider , SmartGridUpdate, and GreenProphet. She has also been published at Ecoseed, NRDC OnEarth, MatterNetwork, Celsius, EnergyNow, and Scientific American. As a former serial entrepreneur in product design, Susan brings an innovator's perspective on inventing a carbon-constrained civilization: If necessity is the mother of invention, solving climate change is the mother of all necessities! As a lover of history and sci-fi, she enjoys chronicling the strange future we are creating in these interesting times. Follow Susan on Twitter @dotcommodity.

http://www.kensan.it Sandro kensan

http://www.youtube.com/watch?v=d2wwWLFGneY

STEM video, STEM is a prototipe of a first Kitegen. The video show the plant with a kite on air.
Susan Kraemer

Great idea, Chris
Susan Kraemer

Great idea, Chris
Chris

Why not add a second kite to the system that can generate power AND pull the first kite back to begin the process again? Like a 2 stroke piston engine, the system would always be generating power.
Chris

Why not add a second kite to the system that can generate power AND pull the first kite back to begin the process again? Like a 2 stroke piston engine, the system would always be generating power.
Chris

Why not add a second kite to the system that can generate power AND pull the first kite back to begin the process again? Like a 2 stroke piston engine, the system would always be generating power.
Velenux

There’s a long article/interview in italian on Sole 24 Ore spinoff “Nova”, a magazine about technologies and such:

http://nova.ilsole24ore.com/nova24ora/2009/07/aquiloni-energetici.html

maybe you can get a comprehensible translation with

http://translate.google.com

or

http://babelfish.altavista.com
Velenux

There’s a long article/interview in italian on Sole 24 Ore spinoff “Nova”, a magazine about technologies and such:

http://nova.ilsole24ore.com/nova24ora/2009/07/aquiloni-energetici.html

maybe you can get a comprehensible translation with

http://translate.google.com

or

http://babelfish.altavista.com
Susan Kraemer

Great info, thanks! The Oil Drum is always a terrific source. Super link, Derek.
http://www.non-scalable.com Derek

Firstly its great to see cleantechnica picking up on this story, ive been following it for the last year; waiting for the tests to come in with some hard numbers.

Theoildrum has a much more in depth look at this project (http://europe.theoildrum.com/node/5538) with some info directly from the prototype run and the developers in the partII.

Quickly to address some recurring questions;

the kite can be “piloted” from the ground mechanically (by the guy-lines) and monitored by computer (unmanned) to find good wind.

When the spool has run-out, the kite is ‘lufted’ and reeled in under far less energy output than what is generated during the ‘pull’ phase (in fact something like an electric motor and regenerative braking-like-system with ultra-capacitors could be employed to power the ‘rewind’ phase).

When the kite has been retracted down to perhaps 600 feet elev. the kite is re-opened to catch the wind and the process begins again.

The ground based generator and control computer can be set up to run more than a single kite, perhaps as many as 5-10 kites computer controlled pulling a line of generators for a constant power output (remember they are computer guided, so twisted lines might not prove to be the problem one would think).

During storm conditions that might damage the air-born assembly, the kite and guy-lines can be completely reeled into a long rigid pole based at the gen.station for protection (pictured in the mock-up). When the winds come down to operation range re-deployment is added by computer controlled fans (pictured) which re-lift the kites the short distance needed to get them high enough for wind power to begin working again.

The guy-lines will most likely be made of Dacron, and longevity testing is a part of the solution phase of this idea being brought to market. Try having a look in google for “heavy kites” to see just how much weight this line can handle and how advanced the state of materials and construction is for kites now-a-days.

Likewise the kite will be fabric and therefore very lightweight “falling to earth” isn’t much of a concern.

Hope these answers have been helpful and drives some interest into thinking of how we can solve the problem of Energy Return On Energy Invested (EROEI) which really is the crux of our situation.
http://www.non-scalable.com Derek

Firstly its great to see cleantechnica picking up on this story, ive been following it for the last year; waiting for the tests to come in with some hard numbers.

Theoildrum has a much more in depth look at this project (http://europe.theoildrum.com/node/5538) with some info directly from the prototype run and the developers in the partII.

Quickly to address some recurring questions;

the kite can be “piloted” from the ground mechanically (by the guy-lines) and monitored by computer (unmanned) to find good wind.

When the spool has run-out, the kite is ‘lufted’ and reeled in under far less energy output than what is generated during the ‘pull’ phase (in fact something like an electric motor and regenerative braking-like-system with ultra-capacitors could be employed to power the ‘rewind’ phase).

When the kite has been retracted down to perhaps 600 feet elev. the kite is re-opened to catch the wind and the process begins again.

The ground based generator and control computer can be set up to run more than a single kite, perhaps as many as 5-10 kites computer controlled pulling a line of generators for a constant power output (remember they are computer guided, so twisted lines might not prove to be the problem one would think).

During storm conditions that might damage the air-born assembly, the kite and guy-lines can be completely reeled into a long rigid pole based at the gen.station for protection (pictured in the mock-up). When the winds come down to operation range re-deployment is added by computer controlled fans (pictured) which re-lift the kites the short distance needed to get them high enough for wind power to begin working again.

The guy-lines will most likely be made of Dacron, and longevity testing is a part of the solution phase of this idea being brought to market. Try having a look in google for “heavy kites” to see just how much weight this line can handle and how advanced the state of materials and construction is for kites now-a-days.

Likewise the kite will be fabric and therefore very lightweight “falling to earth” isn’t much of a concern.

Hope these answers have been helpful and drives some interest into thinking of how we can solve the problem of Energy Return On Energy Invested (EROEI) which really is the crux of our situation.
Susan Kraemer

Great info, thanks! The Oil Drum is always a terrific source. Super link, Derek.
Eletruk

How much power does it take to retrieve the kite? I would assume they will turn it to a less restrictive profile, but still it will have to maintain enough tension to not have is fall to the ground.

And how many reel-in reel-out cycles will the strings/cables/wires withstand before they need replacement?

I don’t know. I would think overall the total efficiency isn’t that great.
Eletruk

How much power does it take to retrieve the kite? I would assume they will turn it to a less restrictive profile, but still it will have to maintain enough tension to not have is fall to the ground.

And how many reel-in reel-out cycles will the strings/cables/wires withstand before they need replacement?

I don’t know. I would think overall the total efficiency isn’t that great.
Susan Kraemer

Actually, I did look through the website to see if there was any verified data on it, but it is really so ephemeral at this point.

As I pointed out, the first test will be in the future.

In general, if until I find the trustworthy hard numbers that some of these lone inventor geniuses can produce, like this guy who came up with another completely new form of energy: from hydrothermal vents…

http://cleantechnica.com/2009/09/04/mining-hydrothermal-vents-for-renewable-electricity-drinking-water-valuable-minerals/

…I don’t pass them along generally.

(For what it’s worth there is mention of “40 kilowatts” in Pop Sci, but at the site that’s not explained…(per yoyo move?) And that’s not much power. I once estimated a church-cum-community center that needed a 35 KW solar power system to supply its needs. 40 KW would only supply about 7 or 8 households.)

So I stick to understanding and passing on just the concept, which in some cases, like this one, is quite a different idea from “the headlines” which did not make it clear that this is a new form of wind power, harnessing the unspooling yo-yo motion each time.
- Jenny Sommer
  
  Susan, maybe you could do some follow up on the kitegen or try to get some new information from skysails who are looking to transform their ship towing kite technology into (off shore) power plants.
  It is sad that kitegen is not publishing news that often. In their last news bit they show the new propose built wing.
  http://kitegen.com/2014/08/29/la-prima-power-wing/
  As I understand they are building a pilot plant in Saudi Arabia and do have a 5GWe baseload carousel plan that they say can be built for 1.5b €.
  A new article or interview with first hand information would really be great.
http://greenhomemegastore.com Craig Hesser

Hello,

My first two questions were

(1) how do you manage a rewind that doesn’t consume all or almost all of the power generated in the unwind phase; and

(2) I can imagine what happens if there is a wind lull – but a relaunch seems like it would take more energy than is produced, plus excessive unscheduled manpower and/or equipment [who’s going to run with the kite to get it relaunched?- sorry, that just slipped out].
http://greenhomemegastore.com Craig Hesser

Hello,

My first two questions were

(1) how do you manage a rewind that doesn’t consume all or almost all of the power generated in the unwind phase; and

(2) I can imagine what happens if there is a wind lull – but a relaunch seems like it would take more energy than is produced, plus excessive unscheduled manpower and/or equipment [who’s going to run with the kite to get it relaunched?- sorry, that just slipped out].
Captain Morgan

@ Bob,

There’s a link to the company’s website and to the original article in Popular Science … if you’re that interested, take some initiative and read up on it. The folks at CleanTechnica are just passing on the headlines.
Captain Morgan

@ Bob,

There’s a link to the company’s website and to the original article in Popular Science … if you’re that interested, take some initiative and read up on it. The folks at CleanTechnica are just passing on the headlines.
http://extremegreenvillage.com Bob

I have seen this idea for last few years and it seems to be a great idea for anywhere there is open unused space.

It is frustrating that the writers of these articles never seem to ask the questions that I would ask.

How much does it cost and how much cost per KW? Or GW or MW or TW?

To me this energy could be a fifth the price of “propeller” windpower.
http://extremegreenvillage.com Bob

I have seen this idea for last few years and it seems to be a great idea for anywhere there is open unused space.

It is frustrating that the writers of these articles never seem to ask the questions that I would ask.

How much does it cost and how much cost per KW? Or GW or MW or TW?

To me this energy could be a fifth the price of “propeller” windpower.
Susan Kraemer

Actually, I did look through the website to see if there was any verified data on it, but it is really so ephemeral at this point.

As I pointed out, the first test will be in the future.

In general, if until I find the trustworthy hard numbers that some of these lone inventor geniuses can produce, like this guy who came up with another completely new form of energy: from hydrothermal vents…

http://cleantechnica.com/2009/09/04/mining-hydrothermal-vents-for-renewable-electricity-drinking-water-valuable-minerals/

…I don’t pass them along generally.

(For what it’s worth there is mention of “40 kilowatts” in Pop Sci, but at the site that’s not explained…(per yoyo move?) And that’s not much power. I once estimated a church-cum-community center that needed a 35 KW solar power system to supply its needs. 40 KW would only supply about 7 or 8 households.)

So I stick to understanding and passing on just the concept, which in some cases, like this one, is quite a different idea from “the headlines” which did not make it clear that this is a new form of wind power, harnessing the unspooling yo-yo motion each time.