PRESS RELEASE  – Jan De Nul Group is installing a total of 72 wind turbines of 8.4MW each for the largest offshore wind farm in Denmark, Kriegers Flak. This week, the company reached its halfway milestone and has 36 windmills to go. 

The turbines are installed on behalf of Vattenfall Denmark. Together, these turbines will produce enough electricity for roughly approximately 600,000 Danish households annually.

On 27 January, Jan De Nul, Siemens Gamesa and Vattenfall successfully installed the very first wind turbine for the Kriegers Flak offshore wind farm. The last turbine is scheduled to be installed in mid-June, approximately 4.5 months after the start of this installation campaign.

This offshore wind farm will become the largest in Denmark and will increase Denmark’s offshore wind production by no less than 16%.

“We are proud that we can tick off this milestone nicely on schedule”, comments Bert Reynvoet, project manager at Jan De Nul Group. “All 72 wind turbines must be installed within a period of 4.5 months. Our customer’s wishes are paramount and despite the challenging winter weather conditions in the Baltic Sea, Covid-19 and challenging soil conditions for our jack-up installation vessel, we have managed until today to strictly adhere to the installation schedule.”

Marshalling harbour

For the first time since its expansion in 2018, the port of Roenne on the Danish island of Bornholm is serving as a marshalling harbour for the construction of an offshore wind farm.

The components of the Siemens Gamesa wind turbines are delivered from Denmark’s mainland. In Roenne, the various parts are assembled. In sets of four wind turbines, they are loaded onboard Jan De Nul’s jack-up installation vessel Vole au vent, after which the vessel sails to the offshore installation site off the Danish east coast.

“When a large installation vessel like the Vole au vent enters a port for the first time, it is always a bit exciting. Moreover, it was new for everyone involved, but thanks to the top service of the port and our local partners, Roenne turns out to be a perfect marshalling harbour”, says Reynvoet.

Long-term cooperation

In 2017 and 2018, Jan De Nul Group already designed, built and installed two large Gravity Based Foundations for the offshore high-voltage substations of this new offshore wind farm.

Jan De Nul built both concrete structures of 8,000 and 10,000 tonnes on a floating pontoon in the port of Ostend (Belgium) and then tugged them to Denmark. The crane vessel Rambiz then installed both foundations on the seabed of the Baltic Sea.

When finished, the Kriegers Flak offshore wind farm will produce 600 MW of electric power. The wind farm is expected to be fully operational by the end of 2021.