Belgian offshore contractor Jan De Nul has installed the first of 53 monopile foundations for the OranjeWind offshore wind farm in the Netherlands using heavy-lift vessel Les Alizés, according to Jan De Nul. Les Alizés transported the foundation from monopile manufacturer Sif’s Maasvlakte II terminal near Rotterdam to the offshore site before installing it on 1 September.
The vessel is working under a long-term charter with RWE. Jan De Nul expects to install all 53 monopiles by early 2027. Each foundation will be about 90 metres long and 8 metres in diameter.
The project uses transition piece-less monopiles, allowing the turbine towers to be bolted directly to the foundations without a separate transition piece and reducing the amount of steel required for each unit.
Les Alizés is equipped with a 5,000-tonne crane reaching more than 160 metres at full height. Jan De Nul’s rock installation vessel Simon Stevin earlier installed a filter layer of scour protection on the seabed to provide stability for construction work and protect against erosion caused by currents and waves.
The contractor’s jack-up installation vessel Voltaire is due to install the wind turbines on top of the monopiles at a later stage.
OranjeWind is being developed as a joint venture between RWE and TotalEnergies. The wind farm is scheduled to become fully operational in early 2028 and is expected to generate enough electricity to supply the equivalent of 1 million Dutch households.
Jan De Nul is a Belgian marine and offshore contractor active in offshore energy, dredging and marine construction.
RWE is a German energy company and co-developer of OranjeWind.
TotalEnergies is a French multi-energy company and joint-venture partner in the project.
Sif is a Netherlands-based manufacturer of steel foundations for offshore wind projects.