After nine months of construction, the last of the 80 foundations for the DanTysk offshore wind farm has been installed.
The up to 65 metres long and up to 950 tonnes heavy, cylindrical steel foundations – monopiles – were anchored in the seabed using a special hammer. Work was done in water depths of up to 32 metres, 70 km west of the German island Sylt.
To protect noise-sensitive harbour porpoises, newly developed technologies for noise reduction were used. In this case, a so-called bubble curtain with up to three rings of air bubbles. They were activated before the start of hammering down the monopiles, and the air bubble curtains has proved to be an effective way of mitigating the disturbing sound for the harbour porpoises.
The offshore wind farm DanTysk is built on an area of 70 square kilometres (approximately 7,000 football fields) in the German Exclusive Economic Zone on the border to Danish territorial waters. The wind farm will have an installed capacity of 288 megawatts and will generate renewable electricity equivalent to the consumption of up to 400,000 German households. Commissioning is planned for autumn 2014. DanTysk is a joint venture by Vattenfall (51%) and Stadtwerke München (49%).
Press Release, December 13, 2013