While the rest of the world was celebrating New Year’s Eve, the crew aboard the installation vessel Svanen was beginning construction on the largest offshore wind farm in Denmark. State-owned Dong Energy announced the installation of the first monopile of the 400-megawatt (MW) Anholt Offshore Wind Farm, sited about 10 miles off the coast of Denmark, between Djursland and the island of Anholt in the Kattegat Sea. With a total of 111 wind turbines, the wind farm will generate enough electricity to power 400,000 Danish households, and meet about 4 percent of the country’s total electricity consumption.
Like other offshore wind farms, the turbines at Anholt will be installed on platforms attached to a monopile foundation. The monopile is a 450-ton round steel pipe with a diameter of about 5 meters and a thickness of 5-9 cm. In order to tow the monopile from the port at Aalborg to the installation site, the ends of the pile are sealed with two end caps. Once the pile is placed at its final position, the caps are removed. The crew then uses a hydraulic hammer to drive the monopile 18-36 meters into the seabed, depending on water depth and seabed conditions.
The Anholt Offshore Wind Farm will play a significant role in helping the Danish government meet its goal of generating 30 percent of its electricity from renewable resources by 2020. The project, which is owned jointly by DONG Energy, PensionDanmark and PKA, is expected to be complete by the end of this year.
“Anholt Offshore Wind Farm is a giant offshore wind farm – even for us – but it’s exactly the capacity we need to speed up the industrialization to ensure that offshore wind power stays competitive,” Christina Grumstrup Sorensen, senior vice president in renewables for DONG, said in a statement. “Now we can take the next step in the development of the Danish energy sector towards a fossil-free energy supply.”