The Nordseecluster combines four wind farm sites in the eastern part of the German North Sea into a 1.6 GW project, consisting of a minimum of 104 wind turbines. In early 2029, once all four wind farms are in operation, the wind turbines will be able to produce enough green electricity each year to supply 1.6 million German households.
The Nordseecluster will be constructed in two phases. The two wind farms (N-3.8 and N-3.7) of Nordseecluster A with a combined capacity of 660 megawatts (MW) are currently in the permit application phase. Two further wind farms (N-3.6 and N-3.5) of the second phase (Nordseecluster B) will add an additional 900 MW of capacity.
Under the agreement, DeepOcean will take charge of preparatory work, transport and installations of all inter-array cables, including trenching, topside pull-ins and terminations for the initial build-out phase. In total, DeepOcean will install 185 kilometers of 66 kV aluminum and copper cables, starting with connecting all 44 offshore wind turbines of Nordseecluster A.
“This is a major contract for us. We have supported RWE in the past and we will apply decades of experience from similar subsea work to deliver the Nordseecluster in line with RWE’s high-quality requirements. We will take charge of a large work scope, which will allow us to secure the best possible project design and exploit operational synergies and costs-efficiencies between the various work packages,” says Normann Vikse, offshore renewables director at DeepOcean.
RWE Offshore Wind Portfolio. Credit: RWE
DeepOcean’s scope of work includes project management and engineering; offshore preparation work including pre-installation cable route survey, route engineering and burial assessment, offshore trenching, boulder relocation, foundation preparatory work and offshore substation preparatory work; transport and installation of inter-array cables including burial, pull-in, monitoring and testing; as well as seabed surveys and monitoring.
Sven Schulemann, Managing Director of Nordseecluster: “We are delighted to have signed with DeepOcean as the last main supplier to install the cables for Nordseecluster A. This is a further important step towards implementing this large-scale project. We are confirmed that DeepOcean is the right partner for us.”
DeepOcean has not disclosed the value of the contract, which is subject to final investment decisions (FID) by RWE. Upon FID, DeepOcean will mobilize a complete engineering, project management and planning team that will support RWE.
In addition, DeepOcean will provide three vessels—installation vessel, trenching vessel and walk to work-vessel—on site to deliver the offshore work. The offshore installation work for Nordseecluster A is likely to be executed in 2026.
“We are very excited about supporting RWE’s plans for the Nordseecluster, where the merger of the four sites offers attractive economies of scale and allows the supply chain to reliably plan and leverage synergies. Awarding the contract for the initial phase with the opportunity to provide our services for Nordseecluster B will allow us to significantly reduce project execution risk. This is a risk-reducing measure that will benefit both RWE and us suppliers,” says Øyvind Mikaelsen, CEO of DeepOcean.