Walney Wind Farm

Walney Wind Farms are a group of offshore wind farms 9 miles (14 km) west of Walney Island off the coast of Cumbria, in the Irish Sea, England. The group, operated by Ørsted[1] (formerly Dong Energy), consists of Walney Phase 1, Phase 2 and the Walney Extension. The extension has a capacity of 659 MW[2] making it the world's second largest offshore wind farm.[2]

Walney Wind Farms
Walney Offshore Windfarm - geograph.org.uk - 2391702.jpg
Walney Wind Farm under construction in 2011
CountryEngland, United Kingdom
Location14km west of Walney Island off the coast of Cumbria
Coordinates54°02′38″N 3°31′19″W / 54.044°N 3.522°W / 54.044; -3.522Coordinates: 54°02′38″N 3°31′19″W / 54.044°N 3.522°W / 54.044; -3.522
Construction beganMarch 2010
Commission dateSeptember 2018
Wind farm
Distance from shore17-18
Rotor diameter107 m; 120 m; 154 m; 164 m
Site area73 km2 (28 sq mi)
Power generation
Units operational102 × 3.6 MW,
47 x Siemens Gamesa 7 MW,
40 x MHI Vestas V164 8.25MW
Make and modelSiemens Wind Power SWT-3.6
Nameplate capacity367 MW (phase 1 and 2)
659 MW (extension)
1,026 MW (total)
Capacity factor
  • 40 %
  • 43 %
Annual net output1,300 GWh (phase 1 and 2)
External links
CommonsRelated media on Commons

The wind farms were developed by Walney (UK) Offshore Windfarms Limited, a partnership between DONG Energy and Scottish and Southern Energy.[3] The farms, which are immediately northwest of the West of Duddon Sands Wind Farm and west of Ormonde Wind Farm, are in water depths ranging from 19m to 23m and cover an area of approximately 73 km2.

Both of the first phases have 51 turbines giving a nameplate capacity of 367 MW.[4] Until September 2012 it was the world's largest operational offshore wind farm, and regained this title when the expansion completed in September 2018.[5][2] The first two phases were expected to generate about 1,300 GW·h/year of electricity, with a load factor of 43%.[6][7][8] The Walney Extension opened in September 2018 with a further 87 turbines capable of generating 659 megawatts.[9]

Development phasesEdit

Phase Offshore construction start Inaugurated Turbines Turbine model Total capacity (MW)
Walney 1[10] 2010 2011 51 Siemens SWT-3.6-107 (3.6 MW) 183.6
Walney 2[11] March 2011 March 2012 51 Siemens SWT-3.6-120 (3.6 MW) 183.6
Walney Extension[12] February 2017 June 2018 87 40 × MHI-Vestas 8.25 MW &
47 × Siemens Gamesa (7 MW)
Total 189 1026.2


In 2004 DONG Energy was awarded a 50-year lease from The Crown Estate to develop a wind farm off Walney Island, as part of the second UK offshore wind farm tendering process known as "Round 2".[13] The farm was constructed sequentially in two phases with overlapping installation activities to reduce the overall construction timeframe.

The project involved constructing the wind turbines and their foundations, building two offshore substations and installing two undersea power cables, one for each phase, and two short onshore cables to connect to two existing onshore Electrical substations for connection into the UK National Grid. A cable was laid by Stemat Spirit. Phase 1 connects to a substation at Heysham and Phase 2 connects to substation at Stanah, south of Fleetwood. Both undersea cables pass close by Barrow Wind Farm. All the construction work was expected to take less than 2 years, with both phases operational by the end of 2011.[14] On 11 July 2011 Phase 1 became operational, comprising 51 turbines with an installed capacity of 183.6 MW.[15] Its levelised cost has been estimated at £120/MWh.[16]

Walney 2 began sending power to the grid on 1 November 2011. In February 2012, DONG Energy claimed to have installed the 51 turbines in Walney 2 in 5 months and 14 days, including monopiles and complete turbines; about 3.25 days per turbine. Walney 1 took 7 months. The improvement is due to commonality of projects and resources.[17] The wind farm was officially opened on 9 February 2012 by the new energy secretary, Ed Davey, MP,[5] although the last of the 51 turbines in Walney 2 were only activated in April 2012.[18]

Walney ExtensionEdit

In November 2014 DONG Energy was given development consent for an extension to the Walney offshore wind farm.[19] The development consent allowed a maximum of 207 turbines to be added to the existing 102 turbines.[19] The maximum generating capacity of the extension was said to be 750 MW although DONG was reported to be proceeding with a project based around 660 MW.[19] Offshore construction began in 2017, onshore support construction having started in 2015.[12] In 2015 DONG chose the 8 MW Vestas V164 for Phase 1,[20] and the 7 MW Siemens gearless turbine for Phase 2.[21] In April 2018, the final turbine of the 87 installed for Phase 1 was completed, with full operation commencing in September 2018.[22]


In 2014 a dive vessel, owned by Danish firm Offshore Marine Services, was carrying out routine inspection work when an anchor cable broke and the ship hit one of 102 turbines installed at the Walney Offshore Wind Farm. The UK’s Maritime and Coastguard Agency surveyed the crash site and reported that a surface sheen stretching 33 feet wide and 0.7 nautical miles long was trailing the vessel. The agency said that, unlike heavier crude oil, the marine engine oil should evaporate or disperse naturally.[23]

See alsoEdit


  1. ^ The World's Biggest Offshore Wind Farm Is Here Archived 2018-09-06 at the Wayback Machine fortune.com, 6 September 2018. Accessed: 6 September 2018.
  2. ^ a b c "World's largest offshore windfarm opens off Cumbrian coast". The Guardian. Archived from the original on 6 September 2018. Retrieved 6 September 2018.
  3. ^ "DONG Energy Project website". Archived from the original on 15 January 2011. Retrieved 20 April 2017.
  4. ^ "UKWED Offshore wind farms". RenewableUK. Archived from the original on 19 March 2011. Retrieved 8 November 2010.
  5. ^ a b World's biggest offshore wind farm opens off Britain as new minister admits high cost Archived 2013-09-21 at the Wayback Machine The Telegraph, 9 February 2012. Accessed: 9 February 2012.
  6. ^ announcement on Walney Offshore Wind Farm Archived 2012-03-23 at the Wayback Machine by DONG Energy . Accessed: 14 February 2012.
  7. ^ announcement on Walney Offshore Wind Farm by SSE. Accessed: 14 February 2012.
  8. ^ Note that the published load factor and expected annual generation do not match well: if the 367-MW wind farm is expected to generate 1,300 GW·h a year, then load factor is a bit smaller than claimed (around 40%).
  9. ^ Walney Extension - 4C Offshore Archived 2018-09-08 at the Wayback Machine, 30 June 2018. Accessed: 8 September 2018.
  10. ^ "Datasheet for site: Walney 1 Offshore Wind Farm". Lindoe Offshore Renewables Center. Archived from the original on 26 March 2011.
  11. ^ "Walney 2 Offshore Wind Farm". Lindoe Offshore Renewables Center. Archived from the original on 2 May 2012.
  12. ^ a b "Walney Extension Offshore Wind Farm" (pdf). Ørsted. 2018. Archived from the original on 8 September 2018. Retrieved 7 September 2018.
  13. ^ "Walney wind farm project history". Archived from the original on 20 January 2011. Retrieved 20 April 2017.
  14. ^ "Walney Project brochure" (PDF). Archived (PDF) from the original on 10 July 2011. Retrieved 20 April 2017.
  15. ^ "Archived copy". Archived from the original on 14 August 2011. Retrieved 23 August 2011.{{cite web}}: CS1 maint: archived copy as title (link)
  16. ^ Aldersey-Williams, John; Broadbent, Ian; Strachan, Peter (2019). "Better estimates of LCOE from audited accounts – A new methodology with examples from United Kingdom offshore wind and CCGT". Energy Policy. 128: 25–35.
  17. ^ Walney opens for business RE News Europe, 9 February 2012. Accessed: 9 February 2012.
  18. ^ Newsletter no 25 - April 2012 Archived 2012-06-04 at the Wayback Machine DONG Energy. Retrieved: 14 June 2012.
  19. ^ a b c "UK OK to Dong's 660MW Walney Extension offshore wind". www.rechargenews.com. 7 November 2014. Archived from the original on 11 February 2015. Retrieved 11 February 2015.
  20. ^ Pedersen, Maria Berg Badstue. "Dong vælger Vestas' supermølle Archived 2015-04-02 at the Wayback Machine" Energy-supply, 18 February 2015.
  21. ^ Pedersen, Maria Berg Badstue. "Napper Dong-ordre med ny supermølle Archived 2015-04-02 at the Wayback Machine" Energy-supply, 12 March 2015.
  22. ^ "Archived copy". Archived from the original on 13 August 2018. Retrieved 12 August 2018.{{cite web}}: CS1 maint: archived copy as title (link)
  23. ^ "Oil Spill Offshore Triggered When Maintenance Ship Hits Wind Turbine Generator". International Business Times. Archived from the original on 8 September 2014. Retrieved 9 September 2014.

External linksEdit