Offshore wind farm
Southern North Sea, UK
The East Anglia Three (EA3) offshore wind farm is being developed in the Southern North Sea, UK, by ScottishPower Renewables, a UK-based subsidiary of Iberdrola.
The project is part of the £6.5bn ($7.7bn) East Anglia Hub, a 3.3GW macro-complex being developed by Iberdrola. The hub comprises the East Anglia Three, East Anglia TWO (EA2) and East Anglia ONE (EA1) projects. The hub is expected to generate up to 7,000 jobs.
Production from the EA3 wind farm is estimated to be sufficient to cater to the clean energy needs of 1.3 million households in the UK. The project is in line with the UK Government’s goal of generating 50GW from offshore wind by 2030.
The UK Government’s Department for Business, Energy and Industrial Strategy (BEIS) granted approval for the project’s development in August 2017.
The onshore construction of the project started in August 2022.
EA3 is being developed in an area of 305km², 69km off the Norfolk county coast in England. It is the second project to be developed in the East Anglia Zone. The first project, the 714MW EA1, was commissioned in 2020.
East Anglia Three offshore wind farm details
The wind farm will have onshore and offshore components. The project plan includes the installation of between 100 and 120 offshore wind turbines with a capacity of 7MW to 12MW each.
The project infrastructure will include four offshore substations as well as an offshore platform with provision for accommodation.
Four subsea export cables will be installed to transmit the power generated from the wind farm to the coast, while interconnector cables will be laid between EA1 and EA3.
A high-voltage direct current (HVDC) onshore converter station will be built at Bramford in Suffolk.
Construction works for the Bramford converter station access road commenced in August 2022. ScottishPower Renewables expects to complete drainage and earthworks by the end of 2022.
The onshore transformer substation at Bramford will connect the wind farm to the national grid.
EA3 and EA1 will have a common landfall site at Bawdsey and follow the same cable corridor.
The 320kV DC export cable system for the project will include 300km of offshore cables and 80km of onshore cables.
Siemens Gamesa Renewable Energy, a subsidiary of Siemens Energy, was chosen as the preferred bidder to supply and install the wind turbines for the East Anglia Hub in February 2021.
ScottishPower Renewables signed a vessel reservation agreement with Cadeler, an installation, operation and maintenance service provider for offshore wind turbines, in July 2022. The agreement covers transportation and installation services for 95 wind turbines for the project. Cadeler will install the turbines using an O-class vessel and newbuild X-class vessel.
Subsea 7’s subsea engineering and construction subsidiary, Seaway 7, signed a letter of exclusivity to finalise a preferred bidder supply chain agreement for the project in June 2022. The contractual scope includes transportation and installation of 95 monopile foundations, along with services such as seabed preparation and scour protection.
The company will also provide engineering, supply and installation services for the inter arrays cables.
A consortium of Norwegian engineering company Aker Solutions and German energy solutions provider Siemens Energy was selected as the preferred engineering, procurement, construction and installation (EPCI) contractor for the HVDC converter platforms in May 2021.
Netherlands-based geological data specialist Fugro started a geophysical survey phase as part of the site investigation works in the East Anglia Hub area in July 2020.
In July 2022, NKT, a cable solutions provider based in Germany, was contracted to produce and install the export power cables for the EA3 project. NKT will design and manufacture a 320kV HVDC export cable system, two 150km offshore cables and two 40km onshore cables. The cable-laying vessel NKT Victoria will be used to lay the offshore cables.
Offshore Design Engineering (ODE), an engineering and operations support services provider, signed an agreement to provide external resources consulting services for the project in May 2017.
Royal HaskoningDHV, an independent consultancy, performed environmental impact assessments (EIAs) for the project.
Offshore wind engineering consultancy Wood Thilsted was initially engaged to conduct a monopiles feasibility study for the project. The company’s scope of work was later increased to provide the full detailed design for the East Anglia Hub.