Van Oord Installs All Monopiles at RWE’s 1.4 GW Sofia Offshore Wind Project

July 15, 2025, by Adnan Memija

All 100 monopile foundations have been installed at RWE’s 1.4 GW Sofia offshore wind farm site, located 195 kilometres off the northeast coast of the UK.

The achievement concludes a 14-month foundation installation campaign carried out by Van Oord as part of a joint engineering, procurement, construction and installation (EPCI) contract for both wind turbine foundations and array cables. With foundation installation complete, Van Oord is now progressing the burial of approximately 360 kilometres of array cables, with completion expected later this year.

The installation of monopiles, manufactured by EEW, started in May 2024 using Van Oord’s jack-up vessel Aeolus. The vessel underwent a project-specific upgrade to its crane system to achieve a 1,650-tonne lift capacity.

Rather than using a monopile foundation topped with an overlapping separate transition piece, an extended single monopile is installed, and secondary steel is fitted offshore. This reduces the total steel tonnage required to complete the project, saving on steel and associated energy resources, said RWE.

During construction, Sofia has deployed a full-scale bubble curtain noise abatement system for 34 foundations, a first for the UK. The technology, operated by Hydrotechnik Offshore, creates a barrier of bubbles that reduces underwater noise during piling operations, helping to protect marine species in the Southern North Sea Special Area of Conservation (SAC), according to the developer.

The installation was carried out from the Port of Tyne, the primary storage and marshalling location for all the foundation components.

The foundations will support Siemens Gamesa’s SG 14-222 DD wind turbines. Half of the turbines will be installed with recyclable blades.

The first turbine was placed on top of a monopile in March 2025, with 27 completed. The work is being performed by Cadeler’s Wind Peak vessel.

First Wind Turbine Up at Sofia Offshore Wind Farm Where Half of Blades Will Be Recyclable

Wind Farm Update

The 1.4 GW Sofia offshore wind farm is located 195 kilometres off the UK east coast in water depths of 20-35 metres and is RWE’s largest offshore project currently under construction globally.

Once fully operational, the generation output of all 100 of Sofia’s turbines will be equivalent to powering up to 1.2 million UK homes with electricity from wind energy, said the developer.