The world’s largest offshore wind park, Horns Rev II, has commenced operations in the North Sea, and is using 91 Siemens wind turbines for generating electricity.
The wind farm has a maximum output of about 210 megawatts (MW), which is enough to meet the electricity needs of approximately 200,000 households.
Each of the turbines from Siemens Energy has a rated output of 2.3 MW. Each turbine weighs 300 tons and rises more than 100 meters above the water’s surface.
The turbines are manufactured by Siemens in Denmark. According to the company, a particularly challenging aspect of the rotor blades is the fact that they must be extremely flexible yet strong in order to handle high winds.
To overcome this difficulty, Siemens uses a patented process in which the rotor blades are made in one piece with alternating layers of balsa wood and fiberglass that are encapsulated in epoxy resin. As a result, the blade does not have any potentially weak areas such as joints or adhesion points.
The rotors are designed to operate reliably for 20 years. According to Siemens, such a high level of reliability is especially important for offshore facilities because maintenance work is about ten times as expensive on the high seas as on dry land.