The United Kingdom became the world leader of offshore wind power generation in October 2008 when it overtook Denmark. It held this lead until 2021 when overtaken by China.

Government direction in the development of offshore wind power advanced in 2016 with the development of strategies and systems.

The total offshore wind power capacity installed in the United Kingdom at the start of 2022 was 11.3GW. By 2023, the United Kingdom had over 11,000 wind turbines with a total installed capacity of 30gigawatts (GW): 15 GW onshore and 15 GW offshore,

The UK has set a target to have 50GW of offshore wind capacity by 2030.

History

The United Kingdom has been estimated to have over a third of Europe's total offshore wind resource, which is equivalent to three times the electricity needs of the nation at current rates of electricity consumption (In 2010 peak winter demand was 59.3GW,National Grid Table of Indicative Triad Demand Information showing 7 January 2010 peak . Bmreports.com. in summer it drops to about 45GW).

One estimate calculates that wind turbines in one third of United Kingdom waters shallower than would, on average, generate 40GW; turbines in one third of the waters between and depth would on average generate a further 80GW, i.e. 120GW in total. An estimate of the theoretical maximum potential of the United Kingdom's offshore wind resource in all waters to depth gives the average power as 2200GW.

The first developments in United Kingdom offshore wind power came about through the now discontinued Non-Fossil Fuel Obligation (NFFO), leading to two wind farms, Blyth Offshore and Gunfleet sands.RenewableUK – Offshore Wind Introduction . Bwea.com. The NFFO was introduced as part of the Electricity Act 1989 and obliged United Kingdom electricity supply companies to secure specified amounts of electricity from non-fossil sources,REPP report into Non-Fossil Fuel subsidies in the UK . Repp.org (30 June 1998). which provided the initial spur for the commercial development of renewable energy in the United Kingdom.

Offshore wind projects completed in 20102011 had a levelised cost of electricity of £136/MWh, which fell to £131/MWh for projects completed in 2012–14 and £121/MWh for projects approved in 20122014; the industry hopes to get the cost down to £100/MWh for projects approved in 2020.

The construction price for offshore windfarms has fallen by almost a third since 2012 while technology improved and developers think a new generation of even larger turbines will enable yet more future cost reductions.Huge boost for renewables as offshore windfarm costs fall to record low The Guardian In 2017 the UK built 53% of the 3.15 GW European offshore wind farm capacity.UK built half of Europe's offshore wind power in 2017 The Guardian In 2020, Boris Johnson pledged that, by the end of the decade, offshore wind would generate enough energy to power every UK home.

In 2013, the 175-turbine London Array wind farm, located off the Kent coast, became the largest offshore wind farm in the world; this was surpassed in 2018 by the Walney 3 Extension.

In 2013 the Offshore Energy Strategic Environmental Assessment (SEA) was first published and has been updated regularly. It is the guiding document from the UK government on offshore energy.

In 2016 the government created the Low Carbon Contracts Company as the party low carbon developers will contract with in the Contracts for Difference (CfD) scheme, the developers having won bids in government auctions. The developers would be paid a flat, index linked rate, for electricity for 15 years. Each contract would have a strike price being the price for electricity reflecting the cost of investing in that specific technology with the developer paid the difference between the strike price and the average market price for electricity.

At the start of 2022 there was a total of 11.26 GW of installed offshore wind capacity. During 2022 an additional 3.2 GW of capacity was added with the commissioning of the Moray East, Triton Knoll and Hornsea Project Two wind farms. A further 13.6 GW of capacity is either under construction (Neart Na Gaoithe, Sofia, Seagreen & Doggerbank A) or has been awarded a Contract for Difference in Round 3 or Round 4.

Offshore wind bidding rounds

In 1998, the British Wind Energy Association (now RenewableUK) began discussions with the government to draw up formal procedures for negotiating with the Crown Estate, the owner of almost all the United Kingdom coastline out to a distance of , to build offshore wind farms. The result was a set of guidelines published in 1999, to build "development" farms designed to give developers a chance to gain technical and environmental experience. The projects were limited to in size and with a maximum of 30 turbines. Locations were chosen by potential developers and a large number of applications were submitted.

Seventeen of the applications were granted permission to proceed in April 2001, in what has become known as Round1 of United Kingdom offshore wind development.

In 2020, the Boris Johnson-led government decided to permit onshore wind power, and since December 2021 onshore wind developers have been able to compete in subsidy auctions with solar power and offshore wind.

Round 1

The first of the Round 1 projects was North Hoyle Wind Farm, completed in December 2003. The final project, Teesside, was completed in August 2013. Twelve Round 1 farms in total are in operation providing a maximum power generating capacity of 1.2GW. Five sites were withdrawn, including the Shell Flat site off the coast of Lancashire.

Round 2

Lessons learnt from Round 1, particularly the difficulty in getting planning consent for offshore wind farms, together with the increasing pressure to reduce emissions, prompted the then Department of Trade and Industry (DTI) to develop a strategic framework for the offshore wind industry. This identified three restricted areas for larger scale development, Liverpool Bay, the Thames Estuary and the area beyond the Wash, called the Greater Wash, in the North Sea. Development was prevented in an exclusion zone between 8 and 13km offshore to reduce visual impact and avoid shallow feeding grounds for sea birds. The new areas were tendered to prospective developers in a competitive bid process known as Round2. The results were announced in December 2003 with 15projects awarded with a combined power generating capacity of 7.2GW. By far the largest of these is the 900MW Triton Knoll. As before a full Environmental Impact Assessment (EIA) would be needed along with an application for planning consent.

The first of the Round 2 projects was Gunfleet Sands II, completed in April 2010 and six others are now operational including the London Array, formerly the largest wind farm in the world. Four other Round 2 sites are currently under construction.

Round 1 and 2 Extensions

In May 2010, the Crown Estate gave approval for seven Round 1 and 2 sites to be extended creating an additional 2GW of offshore wind capacity. Each wind farm extension required a complete new planning application including an Environmental Impact Assessment and full consultation. The sites are: Burbo Bank and Walney: DONG Energy UK. Kentish Flats and Thanet: Vattenfall. Greater Gabbard: SSE Renewables and RWE Npower Renewables. Race Bank: Centrica Renewable Energy. Dudgeon: Statoil and Statkraft.

Round 3

Following on from the Offshore wind SEA announced by the Government in December 2007, the Crown Estate launched a third round of site allocations in June 2008. It followed the success of Rounds 1 and 2, from which important lessons were learnt; Round3 was on a much bigger scale than the combined total of its predecessors (Rounds1 and 2 allocated 8GW of sites, while Round 3 alone could identify up to 25GW).

The Crown Estate proposed nine offshore zones, within which a number of individual wind farms would be situated. It ran a competitive tender process to award leases to consortia of potential developers. The bidding closed in March 2009 with over 40applications from companies and consortia and multiple tenders for each zone. The successful bidders were announced on 8 January 2010.

Following the allocation of zones, individual planning applications still had to be sought by developers. The first zone came on stream in 2018; several more have still to be completed, and some have been abandoned (see below).

Round 3 consortia During the bidding process there was considerable speculation over which companies had bid for the zones. The Crown Estate did not make the list public and most of the consortia also remained silent. The successful bidders for each zone were eventually announced as follows:

+Round 3 wind farms Zone Zone name Wind farm site names Potentialpower (GW) Developer Notes 1 Moray FirthBeatrice 1.3 (0.58) Moray Offshore Renewables Ltd Formed from EDP Renováveis and SeaEnergy Renewables Ltd (SERL)Project scaled down to 588MWCommenced commercial operation in 2018 2 Firth of ForthAlpha/Bravo 3.5 Seagreen Wind Energy LtdPartnership between SSE Renewables and Fluor Ltd. SSE withdrawing support beyond the consent process. 3 Dogger BankCrekye A/B & Teesside A/B/C/D 7.2 Forewind Ltd A consortium made up of SSE Renewables, RWE npower, Statkraft and Statoil.SSE withdrawing support beyond the consent process.Project scaled down to 4.8GW in 2015Expected to commence commercial operation in 2024 4 Hornsea Hornsea One, Two, Three and Four (formerly Heron/Njord/Breesea/Optimus & SPC5/6/7/8) 6 Ørsted (formerly SMart Wind Ltd) SMart Wind was a joint venture between Mainstream Renewable Power and Siemens Project Ventures. 100% acquired in 2015 by DONG Energy, which rebranded as Ørsted in 2017. Hornsea One (1.2GW) became fully operational in December 2019. Hornsea Two (1.32 GW) became fully operational on 31 August 2022. Development consent for Hornsea Three (2.4GW) was granted on 31 December 2020 and Ørsted signed the CfD for the project on 3 August 2022. Hornsea Four remains in development. 5 East AngliaEast Anglia ONE/TWO/THREE/ONE NORTH 7.2 East Anglia Offshore Wind Limited Joint venture between ScottishPower Renewables and Vattenfall ABONE commenced commercial operations in 2020.THREE is currently under construction with commissioning planned for late 2026 Onshore groundwork for TWO and ONE NORTH started in 2025 6 Southern ArrayRampion 0.6 (0.4) E.ON Climate & Renewables / UK Southern Array Ltd Located south of Shoreham-by-Sea and Worthing in the English ChannelCommenced commercial operation in 2018 7 West of Isle of WightNavitus Bay 0.9 Eneco Round 3 Development Ltd West of the Isle of Wight; partnership between Eneco and EDF. Planning permission refused by government in September 2015 due to visual impact. 8 Atlantic ArrayAtlantic Array Channel Energy Ltd (Innogy) Withdrawn in November 2013 as "project uneconomic at current time" 9 Irish Sea Celtic Array Celtic Array LimitedWithdrawn in July 2014 due to "challenging ground conditions that make the project economically unviable". Total 26.7 In 2009, during the Round 3 initial proposal stage 26.7GW of potential capacity was planned. However, due to government planning permission refusal, challenging ground conditions and project financing issues, a number of proposed sites were withdrawn. A number of other sites were also reduced in scope.

Round 4 The Offshore Wind Leasing Round 4 Agreements for Lease signing concluded in January 2023, meaning six new projects could begin to generate renewable electricity by the end of the 2020s.

Three of the six projects are located off the North Wales, Cumbria and Lancashire coast, and three are located in the North Sea off the Yorkshire and Lincolnshire coast.