East Anglia ONE offshore wind project is located in the North Sea, off the coast of Suffolk, UK. Image courtesy of Iberdrola, S.A.
The initial construction works of the project began in 2017. Image courtesy of Scottish Power Ltd.
East Anglia ONE offshore wind farm will have a capacity of 714MW. Image courtesy of Scottish Power Ltd.
The new 66kV/220kV Andalusia II offshore substation has been constructed exclusively for the project. Image courtesy of Scottish Power Ltd.
The £2.5bn ($3.2bn) East Anglia ONE wind farm will be connected to the UK’s national grid by 2020. Image courtesy of Iberdrola, S.A.

East Anglia ONE wind farm is a 714MW project located offshore East Anglia, in the British waters of the southern North Sea. ScottishPower Renewables (SPR), a subsidiary of Iberdrola, is developing the project with an estimated investment of £2.5bn ($3.2bn).

Scheduled to come online in 2020, East Anglia ONE will be one of the biggest offshore wind farms in the world, upon commissioning.

The final investment decision (FID) for the East Anglia ONE wind farm was reached in February 2016, while onshore and offshore construction works for the project were started in 2017 and 2018, respectively.

The offshore wind farm is expected to generate enough clean electricity to power approximately 630,000 British households.

East Anglia ONE will be the first of four proposed wind farms by SPR in the East Anglia offshore wind zone to be brought into operation.

The remaining three projects are East Anglia ONE North (800MW), East Anglia TWO (800MW), and East Anglia THREE (1,200MW). SPR received planning consent for East Anglia THREE in August 2017.

East Anglia ONE background details

SPR, in a 50:50 joint venture with Vattenfall, was awarded the development rights for the East Angila offshore wind zone as part of the UK Crown Estate’s Round Three programme in 2009.

SPR and Vattenfall split the joint venture and agreed to independently undertake the development of projects in the southern and northern areas of the East Angila zone in 2015.

SPR secured the contract for difference (CfD) for East Anglia ONE at a strike price of £119/MWh ($184/MWh) in a competitive auction conducted by the UK Government in the same year.

East Anglia ONE wind farm location and make-up

Spread over 300km² in the southern portion of the East Angila offshore wind zone, the East Anglia ONE wind farm site is located 34km off the coast of the East Anglian county Suffolk.

The offshore wind farm will use a total of 102 SWT-7.0-154 wind turbines from Siemens Gamesa.

Each turbine unit will have a rotor diameter of 154m, blade length of 75m, and hub height of 235m. Rated at 7MW, each turbine will have a swept area of 18,600m².

The turbines are being mounted on 65.5m-long jacket foundations weighing 840t each. Erected in 45m-deep waters, each foundation is supported by three piles.

The electricity generated by the turbines will be gathered and transferred to an offshore substation though 155km of 66kV inter-array cables.

Power transmission

A new 66kV/220kV offshore substation, named the Andalusia II offshore substation, has been built as part of the project. Measuring 53.5m-long, 33m-wide, and 42.5m-high, it is considered to be one of the world’s biggest AC offshore substations.

The installation of the Andalusia II substation was completed in August 2018, using Seaway Heavy Lifting’s Oleg Strashnov crane vessel.

The electricity from the offshore substation will be supplied onshore via two 85km-long underwater cables. It will further be transmitted to a land conversion station using six 37km-long underground cables.

The wind farm will be connected with the UK’s national grid via a new ground substation near Bramford, Suffolk.

Contractors involved

Siemens Gamesa Renewable Energy (SGRE) was contracted for supplying 120 SWT-7.0-154 wind turbines for the East Anglia ONE wind farm in February 2018.

SGRE sub-contracted Global Wind Service (GWS) for assembling towers for the wind turbines in February 2019.

Navantia in joint venture with Windar was awarded a €120m ($134m) contract to manufacture and supply 34 jacket foundations for the wind farm in September 2016.

Lamprell was contracted to fabricate 60 steel foundation jackets for the East Anglia ONE wind farm in November 2016.

Van Oord was contracted for the transportation and installation of the 102 jacket foundations for the wind farm.

Turner Iceni was awarded a £4m ($5.2m) contract for providing the crew transfer vessels to facilitate the construction and commissioning of the wind farm.

The operation and management hub for the wind farm was constructed by 3Sun Group under a £2.5m ($3.2m) contract awarded by SPR.

James Fisher Marine Services received a £3m ($3.9m) contract for providing the marine services for the project.

Cabling and other contractors

VBMS, a subsidiary of Boskalis, was awarded a €100m ($111m) contract in April 2017 for the supply, installation, and testing of 66kV inter-array cables for the project, while JDR was subcontracted for the design and manufacturing of the inter-array cables.

Nexans and DeepOcean were contracted for the fabrication and installation of the two export cables for the wind farm, while Murphy was contracted for the onshore cable connection for the project.

Other contractors and suppliers involved in the project include Visser & Smit Hanab, ODE (a subsidiary of DORIS Group), ERSG, Offshore Wind Consultants, Seaway Heavy Lifting, Gardline, Sparrow Group, Pipeshield, Granada, VolkerInfra, Prysmian, SMC, Seajacks Scylla, Metec UK, and A2Sea.