Seagreen is an

offshore wind farm Offshore wind power or offshore wind energy is the generation of electricity through wind farms in bodies of water, usually at sea. There are higher wind speeds offshore than on land, so offshore farms generate more electricity per amount of ca ...

located in the

North Sea The North Sea lies between Great Britain, Denmark, Norway, Germany, the Netherlands, Belgium, and France. A sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian Se ...

off the coast of

Angus Angus may refer to: *Angus, Scotland, a council area of Scotland, and formerly a province, sheriffdom, county and district of Scotland * Angus, Canada, a community in Essa, Ontario Animals * Angus cattle, various breeds of beef cattle Media * ...

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

, with a rated power of almost 1.1 GW. It is a joint venture between SSE Renewables and

TotalEnergies TotalEnergies SE is a French multinational integrated energy and petroleum company founded in 1924 and is one of the seven supermajor oil companies. Its businesses cover the entire oil and gas chain, from crude oil and natural gas explorati ...

, who were granted exclusive development rights to the

Firth of Forth The Firth of Forth () is a firth in Scotland, an inlet of the North Sea that separates Fife to its north and Lothian to its south. Further inland, it becomes the estuary of the River Forth and several other rivers. Name ''Firth'' is a cognate ...

zone of development by the

Crown Estate The Crown Estate is a collection of lands and holdings in the United Kingdom belonging to the British monarch as a corporation sole, making it "the sovereign's public estate", which is neither government property nor part of the monarch's priva ...

in 2010. Consent for the first phase was granted in 2014, construction commenced in 2021, and the farm became fully operational in 2023. The site is located approximately offshore, East of

Arbroath Arbroath () or Aberbrothock ( ) is a former royal burgh and the largest town in the Subdivisions of Scotland, council area of Angus, Scotland, Angus, Scotland, with a population of 23,902. It lies on the North Sea coast, some east-northeast of ...

. The onshore maintenance base for the project is located in Montrose Port. The Seagreen 1A extension to the wind farm was approved in 2022, with an additional 36 turbines bringing the total capacity to over 1.5 GW.

Technology

The wind farm consists of 114

Vestas Vestas Wind Systems A/S is a Danish manufacturer, seller, installer, and servicer of wind turbines that was founded in 1945. The company operates manufacturing plants in Denmark, Germany, the Netherlands, Taiwan, India, Italy, Romania, the Un ...

V164 wind turbines with a capacity of 10 MW each. The farm has a total capacity of 1,075 MW, and became the largest offshore wind farm in Scotland when it became fully operational in 2023. At that point, it also had the world's deepest bottom-fixed foundations, with a maximum depth of . The turbines are installed on steel jacket foundations, each weighing around 2000 tonnes. The jackets are

tripod A tripod is a portable three-legged frame or stand, used as a platform for supporting the weight and maintaining the stability of some other object. The three-legged (triangular stance) design provides good stability against gravitational loads ...

, with suction bucket foundations, installed in water depth by

Saipem Saipem S.p.A. (Società Azionaria Italiana Perforazioni E Montaggi lit. ''Drilling and Assembly Italian Public Limited Company'') is an Italian multinational oilfield services company and one of the largest in the world. Until 2016 it was a sub ...

. Power is brought ashore via subsea cable to

Carnoustie Carnoustie (; ) is a town and former police burgh in the subdivisions of Scotland, council area of Angus, Scotland. It is at the mouth of the Barry Burn on the North Sea coast. In the UK census 2011, 2011 census, Carnoustie had a population of ...

, then by underground cable to Tealing Substation, north of Dundee.

Horizontal directional drilling Directional boring, also referred to as horizontal directional drilling (HDD), is a minimal impact trenchless method of installing underground utilities such as pipe, Electrical conduit, conduit, or Telecommunications cable, cables in a relativel ...

was used in eight locations of the onshore cable route to pass under obstacles including the main Edinburgh to Aberdeen railway, the A90 and A92 trunk roads, and Barry Links

Site of Special Scientific Interest A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle ...

(SSSI). The principle contract for the cabling work was

Nexans Nexans S.A. is a global company in the cable and optical fibre industry headquartered in Paris, France. The group is active in four main business areas: buildings and territories (construction, local infrastructure, smart cities / grids, e-mobi ...

History

Originally, Seagreen was to be developed as two projects Alpha and Bravo, however these were later combined as the Seagreen 1 project. The adjacent projects, Seagreen 2 and 3 were renamed as Berwick Bank and Marr Bank, then combined under the name Berwick Bank. In 2012, applications were submitted for the Seagreen Alpha and Seagreen Bravo projects. Angus Council granted planning approval in principle for the onshore grid connection works in 2013. In October 2014, the

Scottish Government The Scottish Government (, ) is the executive arm of the devolved government of Scotland. It was formed in 1999 as the Scottish Executive following the 1997 referendum on Scottish devolution, and is headquartered at St Andrew's House in ...

granted planning consent for the offshore works. In 2016, the

Royal Society for the Protection of Birds The Royal Society for the Protection of Birds (RSPB) is a Charitable_organization#United_Kingdom, charitable organisation registered in Charity Commission for England and Wales, England and Wales and in Office of the Scottish Charity Regulator, ...

(RSPB) successfully challenged the plans to build the Seagreen Alpha and Bravo wind farms, as well as nearby Inch Cape and Neart na Gaoithe. This was reversed in May 2017 following appeal by the Scottish Government. In November 2017, RSPB Scotland was refused permission to appeal this decision in the Supreme Court. In 2018, a revised application was submitted to use fewer but larger wind turbines. In September 2019, as part of Allocation Round 3, the project was awarded

Contracts for Difference In finance, a contract for difference (CFD) is a financial agreement between two parties, commonly referred to as the "buyer" and the "seller." The contract stipulates that the buyer will pay the seller the difference between the current value o ...

to supply electricity for 454 MW of capacity, with the first of three phases to be delivered in 2024/25. In 2020, planning consent was awarded for the onshore connection, for the Tealing Substation in January, and for the cable route in June. In October 2021, work started on installation of the jacket foundations. The first two were installed by the semi-submersible crane vessel ''Saipem 7000,'' having been transported by barge from

Broughty Ferry Broughty Ferry (; ; ) is a suburb of Dundee, in Scotland. It is situated four miles east of the City Centre, Dundee, city centre on the north bank of the Firth of Tay. The area was a separate burgh from 1864 until 1913, when it was incorporated ...

Dundee Dundee (; ; or , ) is the List of towns and cities in Scotland by population, fourth-largest city in Scotland. The mid-year population estimate for the locality was . It lies within the eastern central Lowlands on the north bank of the Firt ...

. The jackets were manufactured overseas, and transported via the Port of Nigg, with 23 shipments required for the 114 foundations. In December 2021, the installation of the turbines started, with the final turbine installed in June 2023. First power was generated from the wind farm in August 2022. The Seagreen project was the first Vestas V164-10.0 turbine installed globally, and was also the first turbine rated at 10 MW in Europe.

Seagreen 1A extension

The project was originally proposed to have 150 turbines, but was reduced to just 114 larger turbines producing the same power. There are now plans to extend the wind farm to 1.5 GW with an additional 36 turbines from the original consent for 150. The Marine Licence application for this was approved in December 2021, and the Section 36C consent awarded in October 2022. Also in October 2022, approval was given to increase Seagreen 1A to 500 MW, from the original 360 MW, bring the project total to 1.575 GW. The height and diameter of the turbines now proposed are larger than the existing turbines. The substation for phase 1A will be at the former Cockenzie power station in East Lothian.

Curtailment

A a result of grid constraints, the Seagreen wind farm was curtailed for 71% of the time it was expected to have operated in 2024, leading to payments of £65m. According to the

National Energy System Operator The National Energy System Operator (NESO) is the nationalised energy system operator for the United Kingdom. Previously owned by National Grid plc, when it was known as National Grid ESO, it is a publicly owned organisation which operates both ...

, around 2.4% of consumer bills are spent on curtailment payments.

References

External links