RWE AG has completed the installation of all 72 monopile foundations at the Thor offshore wind farm, located in the North Sea approximately 22 kilometres off the west coast of Jutland. The works, completed in five months, represent a significant milestone in the development of the 1.1-gigawatt (GW) site, currently Denmark’s largest offshore wind project.
Logistical coordination between Danish and Dutch ports
The monopiles, nearly 100 metres long and weighing up to 1,500 metric tonnes, were transported from the heavy-lift terminal in Eemshaven, Netherlands. The installation was carried out by Jan De Nul using the vessel “Les Alizés”. Unlike traditional foundations with a separate transition piece, Thor uses extended monopiles designed to receive secondary steel structures directly. These additional components, such as boat landings, will be installed offshore later this year from the Danish Port of Thyborøn.
Preparation of secondary structures and monopile protection
While waiting for turbine installation scheduled in 2026, the monopiles will be protected with reusable hard covers. Typically designed for single use, these covers have been modified to enable multiple deployments across different projects. Thyborøn also hosts the marine coordination centre responsible for overseeing logistics and sea traffic during the offshore construction phase.
Operations at the site depend on ongoing coordination between maritime contractors and onshore teams. Adherence to the timeline will rely heavily on completing secondary structure installation in the coming months and preparing for turbine integration.
Planning for long-term maintenance at Thorsminde
Ahead of full commercial operations expected in 2027, RWE is constructing a maintenance facility at the Port of Thorsminde. The building is set to accommodate 50 to 60 permanent jobs dedicated to operating and maintaining the wind farm. Construction is underway and scheduled for completion by the end of 2025.
Thor is being developed by RWE AG (51%) in partnership with Norges Bank Investment Management (49%), with RWE overseeing construction and long-term operations. The wind farm is designed to generate the equivalent electricity consumption of over one million Danish households.
