RWE has completed installation of the 100th and final monopile foundation at the 1.4 GW Sofia Offshore Wind Farm. The foundation campaign, which began in May 2024, was carried out over 14 months by Van Oord under an engineering, procurement, construction and installation (EPCI) contract covering turbine foundations and array cables.
Located 195 kilometres off the UK’s east coast in the southern North Sea, the wind farm is RWE’s largest offshore project currently under construction. It will consist of 100 Siemens Gamesa turbines rated at 14 MW each, standing 252 metres tall. Once operational, Sofia is expected to generate enough electricity to power up to 1.2 million UK homes.
The foundations, produced by EEW, are extended monopiles without separate transition pieces. Secondary steel is added offshore, reducing the total steel tonnage required.
For 34 foundations, Sofia used a full-scale bubble curtain noise abatement system—an underwater barrier of bubbles deployed by Hydrotechnik Offshore to reduce noise from piling and protect marine species in the Special Area of Conservation.
Foundation installation was based out of the Port of Tyne. Van Oord is now continuing with burial of approximately 360 kilometres of array cables, with completion due later in 2025.
