Gunfleet Sands Offshore Wind Farm is a 172 MW wind farm about 7 kilometres (4.3 mi) off the Clacton-on-Sea coast in the Northern Thames Estuary.
The 108 MW Gunfleet Sands 1 wind farm gained planning consent in 2003/4; in 2006 DONG Energy (now Ørsted) acquired the project and submitted an application for a second 64 MW windfarm Gunfleet Sands 2 adjacent to the first, which received consent in 2008. Construction of both mounting Siemens Wind Power SWT-3.6-107 turbines took place between 2008 and 2010.
In 2010 planning began on a demonstration project Gunfleet Sands 3, used to test Siemens' 6 MW wind turbine model; two such turbines were installed in 2013.
Gunfleet Sands 1 & 2
Gunfleet Sands 1 & 2 are 7 km southeast of Clacton-on-Sea, Essex; in water at depths of 2 to 15 m (6 ft 7 in to 49 ft 3 in) (given spring-to-neap tidal range of about 4.6 m); Gunfleet 1 consists of 30 turbines in a 5×6 array, whilst Gunfleet 2 consists of a 9×2 array adjacent, to the southeast; the installed capacities are 108 and 64 MW respectively. The average wind speed is 8.8 m/s (29 ft/s) at 60 m elevation.[1]
The turbines connect to a 33 kV offshore substation, which steps up the transmission voltage to 132 kV; the export cable makes landfall at Holland Haven (next to Holland-on-Sea), and underground cables connect it to the National Grid at the Cooks Green substation.[2][3]
Development
Such development near Clacton-on-Sea began in 1996 under Windmaster Developments;[4] Windmaster was acquired by Enron in 2000, and passed to General Electric (GE Wind Energy) in 2002.[5] A Round 1 concession for the development was awarded in 2001, and planning consents obtained in 2003/4.[1][6][7]
In June 2006 a consent application and environmental statement was submitted to the Department of Trade and Industry for permission to build and operate an extension (Gunfleet Sands 2) to the consented project: up to 22 further turbines with an additional capacity of 64 MW.[8] In December 2006 DONG Energy acquired the 100-megawatt "Gunfleet 1" project from GE.[9]
Turbines visible from Clacton-on-Sea beyond Clacton Pier
Construction began in 2008, with initial work including onshore infrastructure and cable installation.[11] A formal groundbreaking ceremony was held in April 2008.[12] The first turbine was installed in April 2009.[13]
MT Højgaard was contracted to instal the monopile foundations; work started in October 2008;[14]Sif supplied the monopiles and transition pieces,[15] and Smulders supplied the wind turbine foundations,[16]
Construction of the wind farm was delayed, due to cable layer Oceanteam going into administration in May 2009 and the breakdown of liftboatKS Titan 2.[20]
Electrical generation began in August 2009.[21] The wind farm was fully operational by March 2010; the wind farm was formally opened on 15 June 2010 by Anders Eldrup (DONG Energy) and the UK's Energy Minister Charles Hendry. Cost of the development was 4 billion Danish Kroner.[22] Large-scale development of British wind farms was enabled by their kickstart subsidies: set in 2010 at a long term rate of 1.20 Danish Kroner per kWh, compared to about 0.50 Kroner (Horns Rev 2) in Denmark.[23]
An operations and servicing center was built in Brightlingsea, Essex where a former boatyard stood.[24][25][26]
Satellite image of the Thames Estuary with Gunfleet Sands top left.
Operational history
The wind farm produced between 450 and 520 GWh between 2010 and 2012, with a capacity factor of 31–35% (2011/12).[27] Its levelised cost has been put at £122 per MWh.[28]
The transmission assets were divested in July 2011 to TC Gunfleet Sands OFTO Limited due to regulatory change.[29]
A planning application for the Gunfleet Sands 3 - Demonstration Project (GFS 3) was submitted in 2010. The project consisted of a wind farm about 1 km2 (0.39 sq mi) 8.5 km southeast of Clacton. It was for testing new wind farm equipment ready for the Round 3 wind farm letting process. Two wind turbine installations were proposed.[33]
The development required a separate export cable and grid connection to the prior farm; a planning application for the onshore electrical facilities and cabling was submitted in November 2011.[34]
Suppliers
Inter-array and export cables (at 33 kV) were supplied by JDR Cables.[35]
The monopile foundations and transition pieces were supplied by Bladt Industries and installed by Ballast Nedam in 2012.[36][37] Two Siemens 6MW turbines were installed in January 2013 by A2SEA.[38]
Productivity
The site began generating power in April 2013.[39] A blade replacement took place in mid 2013 after one of the tips was damaged.[40] The facility was officially opened on 12 September 2013 by UK Energy Minister Greg Barker.[41][42]
^"Wind Energy Power Plants in the UK - offshore". The Power Plants Around the World Photo Gallery (www.industcards.com). Gunfleet Sands. Archived from the original on 29 April 2014. Retrieved 5 October 2016.
^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. doi:10.1016/j.enpol.2018.12.044. hdl:10059/3298.
