Floating wind turbine

A floating wind turbine is an offshore wind turbine mounted on a floating structure that allows the turbine to generate electricity in water depths where fixed-foundation turbines are not feasible.Floating wind farms have the potential to significantly increase the sea area available for offshore wind farms, especially in countries with limited shallow waters, such as Japan.Locating wind farms farther offshore can also reduce visual pollution, provide better accommodation for fishing and shipping lanes, and reach stronger and more consistent winds. Commercial floating wind turbines are mostly at the early phase of development, with several single turbine prototypes having been installed since 2007. As of 2018, the only operational floating wind farm is Hywind Scotland, developed by Statoil and commissioned in October 2017. The farm has 5 floating turbines with a total capacity of 30 MW. The concept for large-scale offshore floating wind turbines was introduced by Professor William E. Heronemus at the University of Massachusetts Amherst in 1972. It was not until the mid 1990s, after the commercial wind industry was well established, that the topic was taken up again by the mainstream research community. Blue H Technologies of the Netherlands deployed the first 80-kW floating wind turbine 21.3 kilometres (13.2 mi) off the coast of Apulia, Italy in December 2007. The prototype was installed in waters 113 m deep in order to gather test data on wind and sea conditions, and was decommissioned at the end of 2008.The turbine utilized a tension-leg platform design and a two-bladed turbine. The first large-capacity, 2.3-megawatt floating wind turbine was Hywind, which became operational in the North Sea near Norway in September 2009. The turbine was constructed by Siemens Wind Power and mounted on a floating tower with a 100 m deep draft, with a float tower constructed by Technip. After assembly in the calmer waters of Åmøy Fjord near Stavanger, Norway, the 120 m tall tower was towed 10 km offshore into 220 m deep water, 10 km southwest of Karmøy, on 6 June 2009 for a two-year test deployment. Alexandra Beck Gjorv of Statoil said, ' should help move offshore wind farms out of sight … The global market for such turbines is potentially enormous, depending on how low we can press costs.' Hywind, owned by Statoil, cost 400 million kroner (around US$62 million) to build and deploy. The 13-kilometre (8.1 mi) long submarine power transmission cable was installed in July 2009 and system test including rotor blades and initial power transmission was conducted shortly thereafter.The installation was expected to generate about 9 GW·h of electricity annually.In 2010 it survived 11 meter waves with seemingly no wear.By 2016, the turbine had produced 50 GWh; an overall capacity factor of 41%. In October 2011, WindFloat prototype was installed 4 km offshore of Aguçadoura, Portugal by Principle Power in approximately 45 m of water (previously the Aguçadoura Wave Farm site). The WindFloat was fitted with a Vestas V80 2.0-MW offshore wind turbine and grid connected. The installation was the first offshore wind turbine to be deployed without the use of any offshore heavy lift vessels as the turbine was fully commissioned onshore prior to the unit's being towed offshore. This is the first offshore wind turbine installed in open Atlantic waters, and the first to employ a semi-submersible type floating foundation. SeaTwirl deployed its first floating grid connected wind turbine off the coast of Sweden in August 2011. It was tested and decommissioned. The design intended to store energy in a flywheel, thus, energy could be produced even after the wind stopped blowing.