After nine months of construction, the last of the 80 foundations at the DanTysk offshore wind farm has been installed.
The monopile foundations, which are 65 metres long and weigh 950 tonnes, were driven into 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 applied. In this case, the so-called bubble curtain with three rings of air bubbles was used. The system was activated before the start of hammering down the monopiles, and the air bubble curtains have proved to be an effective way of mitigating the disturbing sound for the harbour porpoises, according to the developer.