Excerpt:

Google, going beyond its investments in clean energy, has bought an intriguing wind-power company called Makani Power and brought it into the fold of its mysterious Google X research program. Founded in 2006 by some entrepreneurial kite surfers, Makani makes flying wind turbines. They’re essentially giant robot-piloted kites that fly in circles, collecting energy using wing-mounted turbines and transferring it back to earth using a conductive tether. It’s a clean-energy drone.

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Makani, based in Alameda, California, claims that this allows its planes to produce power more efficiently in low winds than conventional windmills, making them more reliable sources of energy. The planes also take far less material to make than a windmill, so the company says they’ll be faster to produce and deploy.