Norwegian oil and gas giant StatoilHydro has inaugurated the world's first floating full-scale offshore wind turbine, paving the way for deep-water wind farms possessing the dual appeal of being out of sight as well as more efficient.

The turbine, known as Hywind, towers 213 feet above the waterline, but the steel spar on which it is mounted plunges another 328 feet below the surface, where it is anchored to the sea floor by three stabilizing cables. The spar is filled with water and rocks to provide ballast that keeps the turbine from capsizing in rough seas. Located about six miles off of Karmoey near the country's southwestern coastline, Hywind will serve as a test bed for offshore technologies over the next two years as engineers work on getting the cost of Hywind down and figure out how best to develop even larger deep-water turbines.