Worlds Largest Wind Turbine Generator

Read about the world's biggest wind turbines - 5MW

RePower 5MW Wind Turbine Generator Nacelle and Rotors

The world's biggest wind turbine generator is currently undergoing testing in the North Sea 15 miles off the East coast of Scotland near the Beatrice Oil Field. This is the first time these enormous offshore wind turbines have actually been tested offshore, and the first time any wind turbine generator has been assembled in such deep water - 44 metres deep. Assembly took place in August 2006.

Similar prototype turbines have been in operation since 2004 in Brunsbüttel, Germany requiring a 1,300 cubic metre concrete foundation constructed of 40 24 metre long concrete piles and 180 tons of steel. A further two 5M offshore wind turbines have recently (December 2006) been erected on the DEWI-OCC test field in Cuxhaven, Germany, and taken into operation. The Cuxhaven site is near to a North Sea dyke and so offers similar wind conditions to those found offshore. There are plans for at least five more of these 5M wind turbines to be installed during 2007.

The German RePower turbines have a power output of 5 Megawatts with a rotor blade diameter of 126 metres sweeping an area of over 12,000 square metres. Maximum power output is achieved at around 30 mph, but a couple of MW are generated even in a fresh breeze. Rotors start turning at around 7 mph, and are automatically braked at 70mph.

Power control is achieved by blade pitching - i.e. turning the rotor blades individually out of very strong wind to prevent the whole structure being damaged. Find out more about power control with our guide to wind turbine furling (1).

Each turbine weighs over 900 tonnes including the 120 metre tall tower which has to be anchored in the deep water. Each turbine blade is 61.5 metres long and weighs under 18 tonnes. LM Glasfiber, the turbine blade manufacturer, has made quite some achievement to keep the weight down so low thereby reducing the financial and environmental costs of building wind turbines

Such large wind turbine generators are ideally suited to the offshore environment thanks to high consistent wind speeds and minimal turbulence. According to historical measures of wind speeds at the Beatrice offshore location, it is expected that the turbines will run an impressive 96% of the time (8440 hours per year), and at 5MW full power 38% of the time (3300 hours per year).

Web Link References

(1) http://www.reuk.co.uk/What-is-Wind-Turbine-Furling.htm

Article from REUK.co.uk:
http://www.reuk.co.uk/Worlds-Largest-Wind-Turbine-Generator.htm
Published: 6th January 2007
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