A kite flown in a strong breeze will quickly unspool string as it climbs higher. KiteGen Research in Italy aims to turn that action into electricity. The company developed a prototype that flies 200-square-foot kites to altitudes of 2,600 feet, where wind streams are four times as strong as they are near ground-based wind turbines.
As the kite's tether unspools, it spins an alternator that generates up to 40 kilowatts. Once the kite reaches its peak altitude, it collapses, and motors quickly reel it back in to restart the cycle. This spring, KiteGen started building a machine to fly a 1,500-square-foot kite, which it plans to finish by 2011, that could generate up to three megawatts—enough to power 9,000 homes.
Any blossom would stand out in the desert of southern Israel, but you'd be hard-pressed to miss a 98-foot-tall one. The tulip-shaped tower is the centerpiece of the world's first hybrid-solar power plant, opened this summer by Israeli start-up AORA Solar. An array of 30 mirrors focuses the sun's rays on the central steel bud. Inside, the solar energy heats air to 1,800ºF, causing it to expand and spin a turbine to generate 100 kilowatts. When night falls or clouds obscure the sun, the plant helps heat the air with a standard diesel combuster running on up to eight gallons per hour to provide consistent electricity output, unlike strictly solar plants. AORA is working with Spanish, Chilean and Australian companies to export the tech, which could be reconfigured to burn biofuel, says Pinchas Doron, the company's chief technology officer. "Soon," he says, "it could be green energy 24/7."
Power on Tap
Power plants often pump more electricity into the grid than consumers demand, and that unused juice fizzles away. Now Beacon Power's energy-storage plant uses that excess to power motors that spin carbon-fiber flywheels. When customers need extra power, the motors stop driving the flywheels and, as the wheels decelerate, convert their motion into electricity. The company recently added 10 flywheels—redesigned to run continuously without overheating—to its two-megawatt facility in Massachusetts, making it the first flywheel system that can feed the grid at any time. Next, Beacon will build a 20-megawatt facility in New York State that could save 33,000 barrels of oil a year.
Great Idea1 I see a few problems, First the power used to reel the kite back in. I hope that that doesn't use up a lot of energy. Also, if its flying up to 2,600ft, what does that mean for flight patterns and traffic around these stations?
Here is the free million dollar idea for the kite power generation plant. Forget winding the kite back up with an electric motor. Use a second kite. As the first kite reaches the end of the line, collapse it and send a second kite out which would pull the first kite in, while generating more power.
I'm liking timias' idea. hah.
greenmachine: they collapse the kite, so the energy lost is negligible.
timias: that's a fine idea, but a) the kites could tangle, and b) you're still losing the same amount of potential energy, but from two kites.
We researched this when I was in college (30 years ago). I had the brilliant idea to do this.
What became the achilles heal was maintenance. A problem alluded to above about tangling. Yes very very large amounts of power can be generated. Kites also extract energy from higher where generally the wind blows faster.
There are some newer materials not available then such as polyethylene used in fishing nets.
I took this further in the 90's and built a prototype for water. I also recieved a patent for the technology, but it has lapsed. The technology is sound in water too, and unlike wind, the water flows all the time. The primary problem is the manpower needed to run it. There is also problems associated with logs or drowned deer floating down the river or loose barges to contend with. These all seem solveable, whether the maintenance costs could get sufficiently low for these mechanisms is a matter of reasonable conjecture. One thing we did discover is that there is indication low head reciprocating technology for water may be able to be designed to reduce fish impacts. The energy potential of low head hydro in the U.|S. is greater than all the installed capacity in the U.S. so there is a strong allure.
Today I am developing another technology for the energy industry.
well, there is a way to reel the kite in without using energy. just rig it up to a device similar to a tape measures, so that it reels it in on a spring, but of course there'd have to be an on/ off switch so that it only comes back when the kite is collapsed.
I was thinking what if they used a kite with a much larger surface area? Would they not then be able to generate the same amount of energy without the necessity of hanging it 2,600 feet in the air?
For instance, imagine a natural draft cooling tower. Air flows into the inlet at the base and rises. What if you hung a very large kite across the diameter of the cooling tower outlet, rigged up to many spring-tensioned lines?
A natural draft cooling tower has issues with cool air sometimes flowing in to the outlet, disrupting the updraft. However, with the kite rigged to spring-tensioned lines (as the other poster said, like a tape measure) you could harness power regardless of which way the kite moved, and in fact if air is forcing the kite down in one area and up in another you should still be able to harness energy from all of the lines as long as force is being applied by a current in either direction (no math to support this, but then this is just a quick brainstorm).
If that concept works, then you would only need to think of ways to increase the updraft to generate more force and more power. To that end designing a large "greenhouse" at the base to trap heat from the sun would create an area of higher temperature low to the ground, funneled upward through the tower.
Just an idea.
what if, lets just say, we take the kite and make it into a balloon, like a mylar balloon. instead of having to wait for wind, you just release a balloon. it would be a matter of gearing the mechanics down enough so that the balloon would be able to pull the rope with enough force to generate the mechanical motion. have a release mechanism that pops out a valve on the top of the balloon when it reaches the end of the cable and it is reeled back in then re inflated and released.
ever watched a weather balloon fly away! they move pretty quickly!
what happened to F=ma on the way up and on the way down. Sorry Newton.
NEW WIND GENERATOR 60% MORE POWERFULL
I think that it is great to see all of these new ideas for clean energy. I also believe that they can work out all of the technical problems. The real problem is that there is always someone or some group that finds a problem with it. It could be the cleanest, safest, cheapest way to generate energy, but they will always find a reason to discredit it. I really wish we could get past this mindset.
A few years ago I conceived of a variation on the kite. It involved four rotors two at the back and two at the front so that they could balance each other to provide a stable craft held aloft by the reaction forces of the wind turning the rotors. I had the tether as a loop , rather than a single cable, and the loop passed round the driving pulley on the "kite" and the driven pulley on the ground. The difference in tension from the upwind strand of the pulley and the downwind strand multiplied by the speed that the cable moved gave the gross power available to turn the generator on the ground. In periods of little or no wind the power flow could be the other way to keep it aloft, or the kite carefully reeled in with a drum mechanism to store the excess cable. Keeping the generator on the ground reduces the load required to keep the kite aloft, but it would still require a transmission to collect the power from the rotors and feed it to the pulley system. I took the idea to one of our universities, but they were unimpressed. If we allow that the cable could take a force of 20,000 newtons ( about 4485 lbf- much stronger cables are available )and we operated at half that, and the cable travelled at 50 meters per second ( 112.5 mph ) it would be transporting 500kw. Many helicoper blades are discarded for safety reasons whilst still able to be used in a lower stressed application such as this where there are no passengers involved.The two strands of the cable should not touch due to the difference in tension, but in the event that the wind started to make them vibrate changing any of the parameters of speed, tension and length should correct for it and be monitored by the operating computer.
WOW it is amazing what they can do now. I am interested in the heating air to run a turbine that powers 70 nearby homes - anyone know where this is? It is about time that we go for a greener future, we cannot reply on gas anymore. Especially in the UK where there is a significant shortage. We have to buy it in from other countries. Great green article and it is so interesting to read the innovations!
Turkey and the US were very old allies, and there could not be any disagreement on the basis of the issues, Tan said. He added that the two countries had some different methods, but their target was same