Flying a kite – often considered child’s play, but the concept could make wind energy cheaper and more reliable than ever before. Correspondent Josh Zepps met the innovators turning the idea of flying a kite into an airborne wind turbine that’s lighter and more powerful than traditional wind turbines.
If you’ve ever flown a kite, you know the strength and consistency of wind hundreds of feet off the ground. What if that same concept could be applied to harness wind power – could it help solve the intermittency, siting, and cost problems that have put a damper on wind energy?
Enter the Makani Airborne Wind Turbine, a design combining kite surfing with wind turbines. Its goal is to achieve the same motion of a turbine, but without the structure itself. A conventional 1-megawatt wind turbine can weigh more than 100 tons, but Makani’s turbine only uses a carbon-fiber wing and lightweight rotors.
The company says its 1-megawatt airborne turbine system will weigh a tenth as much and have an installed price half a normal turbine, but with the same rated power and twice as consistently as the best wind farms operating today.
Imagine a fleet of 26-feet wide, motorized fixed-wing gliders tracing circles in the air at 150 miles per hour, sending a constant stream of electricity to the grid via a tether to the ground. The wing’s rotors function as both propeller and generator: when it launches, they use backup or stored power to reach cruising altitude. At 1,000 feet, they create resistance against the high-altitude winds and generate electricity the same way an electric vehicle generates power from its brakes.
The wings can stay aloft using steady breezes or their own power, but once the wind speed drops below nine miles an hour, they become net consumers of electricity, and would be landed if periods of low wind speed are forecast.
Makani’s future seems bright. Their airborne turbine system won this year’s Breakthrough Award in energy from Popular Mechanics, received a $3 million dollar grant from the Department of Energy’s ARPA-E program, and $20 million in venture capital funding from Google. The company is developing a bigger turbine system to fly at 1,600 feet and produce enough electricity to power 600 homes. It plans to launch a prototype of the new design by 2013 and enter commercial production by 2015.
The full video is available below:
Editor’s Note: This news story comes to us as a cross post courtesy of energyNow! Author credit for the story goes to Josh Zepps.