Construction of the Nordseecluster offshore wind farm cleared a significant milestone this week as RWE successfully installed both offshore substations for the project's first phase, marking what the industry calls a "wedding" the moment a substation topside is placed onto its pre-installed foundation on the seabed.

The Double Wedding

The two installations took place within days of each other, approximately 50 kilometers north of the island of Juist in the North Sea.

The substations, each around 40 meters long and 22 meters high, differ substantially in weight: one topside tips the scales at approximately 1,800 tonnes and the other at around 2,500 tonnes, making them the heaviest components to be placed at the construction site to date.

The platforms were built by French shipbuilder Chantiers de l'Atlantique at its facility in Saint-Nazaire before being transported across the North Sea in a journey lasting approximately one week.

Belgian marine contractor SCALDIS carried out the precision lifting work using its floating heavy-lift crane named Gulliver, setting each topside onto foundations that had already been installed at the end of 2025.

Tobias Keitel, Chief Technology Officer of RWE Offshore Wind, described the event as a visible sign of progress. "At the double wedding, the two heaviest components were installed."

Keitel said, "We will begin installing the first turbines this summer. The first phase of the Nordseecluster will be fully operational from 2027."

Why Two Substations Are Required

The need for a pair of substations is driven by the grid connection architecture of Nordseecluster A. The project will be linked to shore via two separate grid connections, requiring a dedicated substation for each.

Electricity generated by the wind turbines will be fed into the substations, where it will be stepped up to the transmission voltage needed to carry power to the grid operator's converter station and ultimately to the mainland German grid.

Construction Timeline and Current Status

With the substation installations now complete, construction of Nordseecluster A is proceeding across multiple work streams simultaneously. Cable-laying within the wind farm is currently underway, and installation of the 44 wind turbines is scheduled to begin during the summer of 2026.

Full commissioning of Nordseecluster A is targeted for the beginning of 2027, at which point the farm will contribute 660 megawatts of generating capacity.

The second phase of the broader project, Nordseecluster B, is designed to add a further 900 megawatts through 60 wind turbines, with operations expected to begin in early 2029.

Manufacturing of components for Nordseecluster B has already started, and the project received a key regulatory clearance at the end of March 2026 when the Federal Maritime and Hydrographic Agency granted planning permissions, a prerequisite that RWE described as necessary before offshore construction work can begin next year.

Scale and Ownership of the Overall Project

The Nordseecluster is a joint venture between RWE, which holds a 51 percent stake and is responsible for construction and operation across the project's full lifecycle, and Norges Bank Investment Management, which holds the remaining 49 percent.

Together, the two phases will form a 1.6-gigawatt wind energy complex capable of generating enough electricity to supply the equivalent of approximately 1.6 million German households, according to RWE's figures.

RWE's Broader Offshore Portfolio

The Nordseecluster installations form part of a wider program of offshore construction activity for RWE, which describes itself as one of the world's leading players in the sector with more than 20 years of experience in offshore wind development, construction, and operation.

Alongside Nordseecluster, the company is currently building three other large-scale offshore wind projects: the 1.4-gigawatt Sofia project in the United Kingdom; the 1.1-gigawatt Thor project in Denmark, also developed in partnership with Norges Bank Investment Management; and the 795-megawatt OranjeWind project in the Netherlands, developed in collaboration with TotalEnergies.

Discover Latest Offshore Wind Farm Projects in Germany With Ease

Are you seeking reliable, up-to-date insights into upcoming offshore wind farm projects in Germany?

Explore the Global Project Tracking (GPT) platform by Blackridge Research, your go-to resource for the latest offshore wind farm projects and tenders across all stages:

• Upcoming Projects

• Tender Notices

• Contract Awards

• Projects Under Construction

• Completed Projects

Book a Free Demo today and see how the GPT platform can help you unlock opportunities and achieve your business goals.