The Norwegian energy company Statoil has begun operation of the first full-size Hywind floating wind turbine at a location 10 kilometres off the Norwegian coast. What is remarkable about this turbine is that it is floating in the water, rather than being rigidly attached to the ocean floor.
In fact, this turbine can be found in the depths of the sea, where a 100m long steel cylinder, weighing 3,000 tonnes thanks to its ballast of water and rocks, is anchored to the sea-bed with mooring lines that can hold the structure at depths of up to 700m.
So-called slack anchors are used, allowing the structure to move with the seas. In fact, in spite of its apparent sturdiness, the 138 tonne turbine is constantly moving.
Everything below the water line is known technology from the oil and gas industry, where StatoilHydro has 30 years of experience from its extensive offshore operations around the world.