Sofia

Sofia Offshore Wind Farm Profile

Location and Site Details

• The Sofia Offshore Wind Farm is located on Dogger Bank, approximately 195 kilometers off the north-east coast of the UK in the central North Sea. It is situated near other Dogger Bank wind farms, including Dogger Bank C.

Project Details

• The Sofia Offshore Wind Farm is a 1.4 GW offshore wind power project, making it one of the largest offshore wind farms in the world. The project is currently under construction and is expected to be fully operational by 2026.

Ownership and Development

• The project is 100% owned by RWE Renewables UK Swindon, previously developed by Innogy, which is now part of RWE. The development consent order (DCO) was obtained by Forewind, a consortium between SSE, Equinor, Statkraft, and Innogy, in August 2015. Innogy secured 100% ownership of the project in August 2017.

Financial and Investment

• The project involves an estimated investment of £3 billion ($3.7 billion). The financial investment decision (FID) was made in March 2021, and the official ground-breaking took place in July 2021.

Capacity and Impact

• Upon completion, the wind farm will generate 5.4 terawatt-hours of electricity annually, sufficient to power approximately 1.2 million UK households. It is expected to offset around 2.5 million tons of carbon dioxide emissions per year.

Turbines and Technology

• The wind farm will feature 100 Siemens Gamesa SG 14-222 DD offshore wind turbines, each with a rated capacity of 14 MW. These turbines are 262 meters tall, with 108-meter-long carbon and fiberglass blades and a rotor diameter of 222 meters, sweeping an area of 39,000 square meters. The turbines will be mounted on fixed monopile foundations and interconnected by 66kV inter-array cables.

Infrastructure and Construction

• The project includes an offshore converter station, onshore electrical infrastructure, and inter-array and export cables. The offshore platform will feature a 17,000-ton topside and jacket foundation structure. Van Oord is the EPCI contractor for the monopile foundations and array cables, using the offshore installation vessel Aeolus. Cadeler is contracted to transport and install the turbines, while Heerema Marine Contractors will transport and install the HVDC offshore converter platform using the semi-submersible crane vessel Sleipnir.

Contractors and Suppliers

• Key contractors include:
  • Siemens Gamesa: Manufacturing, installation, and commissioning of the turbines, along with a comprehensive service and maintenance contract.
  • GE Renewable Energy’s Grid Solutions and Sembcorp Marine: Supplying the HVDC electrical transmission system, including two HVDC converter stations and the offshore converter platform.
  • Prysmian: Designing, supplying, installing, and commissioning the HVDC cable system connecting the onshore and offshore converter stations.
  • Van Oord: Installing monopile foundations and array cables.
  • Cadeler: Transporting and installing the turbines.
  • Heerema Marine Contractors: Transporting and installing the HVDC offshore converter platform.
  • Fugro: Providing geophysical and geotechnical services, including site investigations.

Construction Timeline

• The final phase of the pre-construction site investigation was completed by July 2020. Offshore work began in 2023, with the installation of the first turbine foundation taking place in May 2024. The project is expected to be fully operational by the end of 2026.

Power Purchase Agreement

• The power generated from the project will be sold to EDF Energy UK under a power purchase agreement for a period of 15 years.

Operations and Maintenance

• Operations and maintenance activities for the wind farm will be based at RWE’s new offshore wind operations base, the ‘Grimsby Hub’, which also supports other RWE projects.

Environmental Impact and Benefits

• The project will significantly reduce greenhouse gas emissions and provide a sustainable energy source, contributing to the UK’s Net Zero ambitions and energy security goals. RWE aims to triple its global offshore wind capacity from 3.3 GW to 10 GW by 2030, with Sofia being a key project in this strategy.