The Makani Airborne Wind Turbines, which resemble a fleet of mini airplanes, are launched when wind speeds reach 3.5 meters per second. Rotors on each blade help propel it into orbit, and double as turbines once airborne. The blades are tethered to the ground with a cord that delivers power to throw them into the sky and receives energy generated by the turbines to be sent to the grid-connected ground station.

via Kite-Like Turbines Harness Wind Power At Altitude | TechCrunch.