Huge Kites: a Soaring Energy Solution?
By Don Willmott on August 21, 2015
Somewhere Benjamin Franklin is smiling. Back in 2013, Google purchased a company called Makani, the creators of one of the cooler alternative energy devices you’ll ever see: the Energy Kite. Part wind turbine, part model airplane, the Energy Kite flies way up high in huge circles as it captures steady winds to send power back down to the ground. It’s lightweight, portable, and easily deployable.
The kite uses 90 percent less material than a typical wind turbine and yet can generate 50 percent more power—perhaps 600 kilowatts—according to the company. How? By flying much higher—up to 350 meters—than any wind turbine could ever hope to reach and by being extremely efficient. It’s as if only the tip of a wind turbine blade was looping around in the sky. The rest of the turbine—all those tons of steel—simply disappears from the equation.
The kite is launched from its ground station using its rotors for lift, but once it begins to soar on the wind, those rotors become mini wind turbines and drive generators that produce electricity. The juice is then sent back down the wire. And unlike your childhood kite, this kite knows where it’s going. Its flight path is guided by a computer that uses a GPS and sensors to constantly recalculate the best path for optimum efficiency. As for maintenance, well you certainly don’t need a crane or helicopter—you just reel it back down to the ground.
At the SXSW conference in March, Google X head Astro Teller said that testing would begin on an 84-foot kite in Pesacadero, California later this year.
Perhaps the biggest advantage of the Energy Kite is that, according to Makani, in the continental United States alone, the kite can generate wind power economically in over 66 percent of the landmass, more than four times the area available to conventional wind turbines. However, and it’s a very big however, Federal Aviation Administration rules may make deployment extremely difficult on land, demanding such things as 5,000 feet of clearance from any trunk power line or public road. You can understand the concern. It’s disconcerting to imagine a nearly invisible electrified line sweeping across the landscape at an incredible rate of speed. Another concern is noise: it isn’t exactly silent. It could turn out, then, that best place for the Energy Kite is offshore, perhaps off the shores of Hawaii. After all, “makani” is Hawaiian for “wind.”
Don Willmott is a New York-based journalist who writes about technology, travel, and the environment for a wide variety of publications and websites.