Update May 2008: The UK Crown Estate has agreed to buy what is expected to be the world’s largest wind turbine (offshore).
The Crown Estate signed a deal with Clipper Windpower, which has its headquarters in California, to buy the prototype 7.5MW turbine, known as the Britannia project… more to follow shortly!
Also, the Fluor Corporation,from Dallas in the US has signed a contract with the Scottish and Southern Energy (SSE) to design and construct a 500 megawatt (MW) Greater Gabbard Offshore Wind Farm. This venture is now the world’s largest offshore wind farm project to move into the construction phase and will be built approximately 25 kilometers off the Suffolk coast of the United Kingdom (UK). The new award is worth approximately $1.8 billion US dollars(£900 million).
The 5M is currently the largest wind turbine (installed) in existence, with a rated output of 5 megawatts, a rotor diameter of 126 meters (413 feet), and a hub height of around 90 meters (295 feet) at sea and 120 meters (393 feet) on land. The turbine is made by REpower Systems and the development is co-financed by the European Union and the German state Schleswig-Holstein.
The rotor comprises three rotor blades that are each 61.5 meters (201 feet) in length, and a cast rotor hub. All installed components, including the individual electrical blade pitch system for example, are safely protected against external influences by an enclosed GRP cowling known as the “spinner”. The three rotor blades, weighting 18 tons each, are made from a glass/carbon fiber hybrid fabric together with synthetic resins. This innovative material structure has enabled significant weight reductions.
The world’s largest wind turbine, the 5M (being constructed above) has a die-cast, hollow rotor shaft that also enables a large reduction in weight. Dual bearings on the shaft minimize the rotor loads in the gearbox. If required, it is also possible to remove the gearbox without dismantling the rotor. The turbine is equipped with a variable speed generator-inverter system as well as a individual electrical blade pitch system. The inverter and transformer are located in the nacelle.
Eight electric geared motors are used for tracking the wind. Eight hydraulic brake calipers are used to hold the nacelle facing the wind. These prevent any unrequested loads on the drives in turbulent wind conditions. The drives are also fitted with electromagnetic multiple disc brakes.
The Beatrice Project
REpower is participating in the “Beatrice Demonstrator Project” to test the performance of the 5 megawatt turbine on the open sea and to take a step closer to achieving its goal of making wind energy competitive. Two 5Ms are to be installed near the Beatrice oil field in Moray Firth, 25 kilometres off the Scottish East coast and at a water depth of over 40 metres.
The demonstrator project is part of the EU-supported “DOWNVinD” project, Europe’s largest research and development programme in the field of renewable energies with a total volume of EUR 30 million. Talisman Energy (UK) and Scottish & Southern Energy (SSE) are the coordinators of the project, in which a large number of research and development organisations are participating from all over Europe. This in n addition to the onshore prototype erected in Brunsbüttel (Schleswig-Holstein) in 2004. the installation of at least a further six 5M turbines are planned for 2007.
Clipper Windpower Plc also announced in October 2007 that it has established a Centre of Excellence for Offshore Wind in Blyth, United Kingdom, to develop a massive offshore wind turbine at 7.5 MW. The “Britannia Project” has attracted support from the UK’s One NorthEast Regional Development Agency.
Go wind power!