Van Oord’s Svanen to start work at Danish offshore wind farm

Van Oord’s heavy lift installation vessel Svanen has arrived at the Danish Kriegers Flak Offshore Wind field in the Baltic Sea. The Svanen will commence installation works for the foundations for the offshore wind farm.

Van Oord was contracted by Vattenfall for the transport and installation of the foundations for Kriegers Flak wind farm. Van Oord will install the 72 monopiles and transition pieces. With a production capacity of just over 600 MW, Kriegers Flak will be Denmark’s largest offshore wind farm and is scheduled to be fully operational in 2021. It is constructed in the Baltic Sea across a range of 15 to 40 kilometres from the Danish coast.

The monopiles of up to 800 tonnes will be transported floating from Rostock, Germany, directly to the offshore site. The transition pieces will be transported on barges from Aalborg, Denmark. In April, Van Oord’s subsea rock installation vessel Bravenes started the installation of the seabed protection.

Noise mitigation

Van Oord’s 8000-tonne lift installation vessel was added to the Van Oord fleet in the Summer of 2016. In 2017 the vessel was modified. The adjustments included the installation of two spreader beams at the main hoists to hoist 2000 tonnes each, a new skidding gripper, suitable for monopiles with a length up to 90 metres and diameters between 7 and 11 metres (bottom part), and is complemented with a skidding hammer platform for hammers with a maximum weight of 1200 tonnes.

The gripper can be equipped with a noise mitigation system, which will also be used on this project. The system uses special acoustic resonators that reduce the underwater noise resulting from offshore pile driving.

So far, the vessel has installed approximately 650 foundations throughout Europe, of which the vast majority of monopiles in the Baltic Sea including the Anholt, Baltic 2 and Arkona projects. More wind farm projects are expected to be launched in the Baltic in the near future.

Author: Mariska Buitendijk

Mariska Buitendijk is one of SWZ|Maritime's journalists as well as the magazine's copy editor.