Jan De Nul Group has signed an agreement with RWE for the long-term chartering of two next-generation installation vessels for future offshore wind foundation and turbine construction. It involves the exclusive charter of Les Alizés and Voltaire.

The charters are supported by a Service Agreement through which Jan De Nul will provide both in-house and market solutions and services, to support and perform installation campaigns for RWE’s offshore wind projects.

Both Les Alizés and Voltaire can be used at RWE’s current and future offshore construction projects and, if needed, to run maintenance campaigns at its existing offshore wind farm portfolio.

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‘We are delighted to further step up our contribution to the worldwide energy transition through this long-term partnership,’ says Philippe Hutse, CEO of Jan De Nul Offshore Energy. ‘This multi-year approach creates much-desired planning security for our state-of-the-art installation vessels and will allow safe and efficient installation of a large number of offshore wind farms.’

Sven Utermöhlen, CEO RWE Offshore Wind: ‘Europe needs more offshore wind power to reach its ambitious climate targets. We are already making a significant contribution and resolutely driving forward the future build-out of offshore wind in Europe and globally. Through this strategic partnership, RWE has taken a big step in securing the necessary installation vessels and services to deliver our large-scale offshore wind farms Thor and Hollandse Kust West VII, as well as further projects to come. These kinds of agreements are exactly what we need against the backdrop of the challenging market situation.’

Les Alizés

Les Alizés has been chartered for more than five years, and is a purpose-built vessel designed for transporting, lifting, and installing wind turbine foundations. With the ability to lift up to 5000 tonnes and with a deck loading capacity of 61,000 tonnes, it is capable of handling the scale and design of future foundations that will support the next generation of wind turbines.

Heavy lift vessel Les Alizes of Jan De Nul Group_

Les Alizés’ first project will be the Danish offshore project Thor. Foundation installation works for this 1000MW wind farm are due to take place in 2025.

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Voltaire is the world’s largest jack-up installation vessel with a crane capacity of 3200 tonnes and approximately 130-metre-long legs. Its innovative design makes the vessel highly suitable for the installation of next generation wind farms in deep waters. It has been chartered to RWE for more than four years, from 2027 onwards. Subject to the project’s final investment decision, Voltaire will install the turbines of RWE’s Hollandse Kust West VII wind farm off the Dutch coast.

With this framework agreement, the two companies are continuing their cooperation. During 2021 and 2022, Jan De Nul Group provided installation services supporting the construction of RWE’s offshore wind farm Kaskasi off the German coast. More recently, Jan De Nul Group has been awarded with the export and inter-array cable installation scopes on RWE’s Thor offshore wind farm.

Picture (top): Jan De Nul Group’s next-generation installation vessel Voltaire.

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