Zothecula (1870348) writes "Wind can be an unpredictable and unstable source of power, and high in the sky where it is more stable, it's difficult to exploit. Airborne wind turbines could provide a solution to this problem, but although the idea has been around since the 19th century, it's never been exploited on a larger scale. California's Makani Power aims to change that with its innovative flying wing turbine design. Wing 7 is essentially a cross between a UAV and a wind turbine that's tethered to a ground station from which it ascends to a height of around 1,300 feet (400m) and flies autonomously, generating up to 20-kilowatts of power in a 20mph (35km/h) wind."
Link to Original Source