Sheringham Shoal offshore wind farm is located in the Greater Wash, off the Norfolk coast in the UK.

The 317MW project produces around 1.1-terawatt hours (TWh) of renewable energy per annum, enough to power 280,000 British homes.

The lease for the project site was granted as part of The Crown Estate Round 2 in 2004. The necessary approvals for the construction of the project were received by 2008 after four years of planning and development.

Construction works commenced in 2009 and the wind farm began commercial operations in late summer 2012.

Sheringham Shoal Offshore Wind Farm was developed with an investment of £1bn ($1.26bn).

Equinor, Green Investment Group and Equitix own the project through their joint-venture Scira Offshore Energy. The wind farm is operated by Equinor.

Location and Site details

The Sheringham Shoal Offshore Wind Farm is located between 17km and 23km off the coast of North Norfolk in the UK. The site is situated around 5km north of the offshore sand bank known as Sheringham Shoal. Water depth is relatively shallow ranging between 17m and 22m.

The site of the project is diamond-shaped, spread over an area of 35km2.

Project details

The wind farm consists of 88 turbines, each with 3.6MW capacity. Each of the turbines is composed of an 80m tower, the nacelle and three 52m long blades.

The turbines are based on foundations that are fixed to the seabed. The foundations comprise a tubular steel monopile that is driven 23-37m into the seabed, and a transition piece mounted on top.

The 375 to 530-tonne monopiles have a length ranging between 44m and 61m, while the 22m-long transition pieces are 22m high and weigh about 200 tonnes.

The offshore infrastructure of the wind farm includes two 900-tonne substations with two 132kV marine cables that make landfall at Weybourne.

A 21.6km long underground cable connects the landfall point at Weybourne to the onshore substation at Salle, near Cawston. Subsequently, the onshore substation feeds the power to local 132kV UK Power Networks distribution network from where it is transported to the national grid.

The project helps in reducing carbon dioxide emissions by 500,000 tonnes annually.

Construction of the wind farm

The construction work at the wind farm site began in March 2010 when the 164m Nordnes vessel arrived to place rocks at selected foundation locations. Around 3 to 9-inch filter rocks were placed to enable the site hold giant monopile structures, protect the cables and prevent scouring.

The first phase filter layer work was conducted by Van Oord.

The installation of the foundations began in June 2010. Seaway Heavy Lifting Contracting used crane vessel Oleg Strashnov to transport foundations and transition pieces to the site.

The foundations were placed around 700m apart each.

Offshore support vessel GMS Endeavour transported wind turbines to the location for installation, while the substations were transported aboard the barge Dina Launcher and then lifted onto their individual foundations and installed during 2010.

The installation of the two export cables was completed in late 2010.

The underground cable system was installed by open-cut trenching across cultivated agricultural land. The onshore substation was also commissioned in late 2010.

Turbine installation work began in mid-2011 and the wind farm became fully operational in late summer 2012.

Key Contractors Involved

The Sheringham Shoal offshore wind farm is equipped with 3.6MW Siemens wind turbines.

Rambøll Group was selected for the project’s detailed foundation design of monopiles and substations for the wind farm.

The monopole structures and the transition pieces were fabricated by the Sif group at its Roermond plant in the Netherlands.

Subsequently, the transition pieces were transported to Smulders in Belgium for outfitting. Smulders delivered 88 foundations for the wind project in 2010.

The foundations and the offshore substation structures were delivered by MT Højgård.

Nexans was contracted for power export cables, infield cables and ancillary equipment, while Carillion Utility Services received the order to deliver onshore cables.

Areva T&D UK supplied key equipment for the offshore substation platforms and onshore substation.

Alstom began maintaining the onshore and offshore substations of the 317MW wind farm in 2011. In 2015, the company signed a three-year service extension.

3sun Group won a three-year operational services contract for the offshore wind farm, effective from 1 January 2013.

Expansion of Sheringham Shoal wind farm

In September 2022, Equinor applied to the UK’s Planning Inspectorate seeking permission to build extensions of the Sheringham Shoal and the Dudgeon Offshore Wind Farms.

The 402MW Dudgeon wind farm, operated by Equinor, is also located in the waters of the Greater Wash off the coast of Norfolk.

The application was accepted for examination a month later in October 2022.

If implemented, the Sheringham Shoal and Dudgeon Offshore Wind Farm Extension Projects (SEP and DEP) will double the existing capacities of the wind farms.

This will help in providing green electricity to an additional 785,000 UK homes.