DEME Offshore carried out the transport and installation of 60 Siemens 6.0 MW turbines for the Arkona offshore wind farm on behalf of client AWE (E.ON and Equinor).
The wind farm is located 35 kilometres offshore in the Baltic Sea – halfway between the German island Rügen and the Danish island Bornholm. The wind farm occupies an area of 39 m2 and comprises 60, 6.45 MW Siemens Gamesa turbines with a total capacity of 385 MW.
When fully completed, Arkona will provide electricity to approximately 400,000 German homes.
In July 2018, the offshore installation vessel ‘Sea Challenger`installed the first turbine at the wind farm, and only three and a half months later, the last turbine was successfully installed .
The first half of the turbines were already installed by the end of August, largely due to the summer weather conditions. The installation of the second half of the turbines faced more autumnal conditions. There was a certain amount of ‘waiting on weather’ given the wind sensitive operations involved due to the 75- metre-long turbine blades having to be installed at a 90-m height. In addition, the second half of the turbines was installed in the part of the site with a more difficult seabed/soil composition, resulting in a penetration of up to 14 m compared to a maximum of 6 m in the first half of the project.
Fortunately, the weather continued to be favourable and the project stayed ahead of schedule, and on 20 October 2018, the last turbine was installed. Eventually, 60 turbines were installed in less than four months in a really impressive performance thanks to a well-performing vessel and team.