RWE has taken an important step in the construction of the 1.1 GW Thor offshore wind farm in the Danish North Sea as, over the past five months, all 72 monopile foundations for the wind turbines have been installed.
Dr Tobias Keitel, Chief Technology Officer RWE Offshore Wind, commented: “Together with our partner, Norges Bank Investment Management, we are well on track with the construction of Thor – Denmark’s largest offshore wind farm to date. The safe installation of the monopiles is testament to the expertise, dedication, and collaboration of the entire team involved.”
The monopiles are around 100 m in length and weigh up to 1500 t each. This is roughly equivalent to the weight of 1000 small cars. The monopiles were shipped from the heavy-lift terminal in Eemshaven, in the Netherlands, to the Thor construction site in the Danish North Sea. Located approximately 22 km off the west coast of Jutland, the installation of the monopiles was completed by Jan De Nul with their vessel, Les Alizés.
Rather than using a monopile foundation topped with an overlapping separate transition piece, extended single monopiles were installed and secondary steel structures, including boat landings, will be fitted offshore. Secondary steel structures for the Thor foundations are being handled from the Danish Port of Thyborøn and installation works will be completed later in 2025. The control centre for managing marine logistics and traffic throughout the offshore construction phase is also based in Thyborøn.
To protect the monopiles from the harsh conditions at sea until the turbine towers are mounted in 2026, innovative reusable hard covers will be installed. Usually, the covers are disposed of after use because they are tailor-made to a specific offshore project. The covers used at Thor are reusable and so reduce waste and increase circularity whilst the initiative exemplifies RWE’s dedication to sustainable practices.
The turbine installation works are scheduled to be carried out from the Port of Esbjerg in Denmark, starting in 2026. Thor will be the first offshore wind farm in the world to use 36 turbine steel towers that have been manufactured with a lower carbon footprint. In addition, half of the turbines will be equipped with recyclable rotor blades.
When fully operational in 2027, Thor offshore wind farm will be capable of producing enough green electricity to supply the equivalent of more than 1 million Danish households. The wind farm’s operations and maintenance plan predicts that it will create 50 to 60 local jobs in a new service building at the Port of Thorsminde. Construction of the new RWE service building is already underway, and is scheduled to be finalised by the end of 2025.
Thor offshore wind farm, which will have a capacity of 1080 MW, is a joint project of RWE (51%) and Norges Bank Investment Management (49%). RWE is in charge of the construction and operations throughout the lifecycle of Thor offshore wind farm.
RWE already has 19 offshore wind farms in operation globally, including Rødsand 2, located south of the Danish island of Lolland. In addition to Thor in Denmark, the company is currently building three major offshore wind farms: the Sofia offshore wind farm (1.4 GW) in the UK, the Nordseecluster (1.6 GW, RWE share: 51%) off the German coast, and OranjeWind (795 MW, RWE share: 50%) in the Netherlands.
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