Wind power in the United Kingdom

Burbo Bank Offshore Wind Farm.

The total offshore wind power capacity installed in the United Kingdom at the start of 2022 was 11.3 GW. The United Kingdom became the world leader of offshore wind power generation in October 2008 when it overtook Denmark.[50] 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.

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[51] (In 2010 peak winter demand was 59.3 GW,[52] in summer it drops to about 45 GW). One estimate calculates that wind turbines in one third of United Kingdom waters shallower than 25 metres (82 ft) would, on average, generate 40 GW; turbines in one third of the waters between 25 metres (82 ft) and 50 metres (164 ft) depth would on average generate a further 80 GW, i.e. 120 GW in total.[53] An estimate of the theoretical maximum potential of the United Kingdom's offshore wind resource in all waters to 700 metres (2,300 ft) depth gives the average power as 2200 GW.[54]

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.[55] 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,[56] which provided the initial spur for the commercial development of renewable energy in the United Kingdom.

Offshore wind projects completed in 2010–2011 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 2012–2014; the industry hopes to get the cost down to £100/MWh for projects approved in 2020.[57]

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.[58] In 2017 the UK built 53% of the 3.15 GW European offshore wind farm capacity.[59] In 2020, Boris Johnson pledged that, by the end of the decade, offshore wind would generate enough energy to power every UK home.[60]

At the start of 2022 there was a total of 11.26 GW of installed offshore wind capacity.[48] 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.[61][62][63] 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[64] or Round 4.[65]

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 12 nautical miles (22.2 km), 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 10 km² (3.9 square miles) 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 Round 1 of United Kingdom offshore wind development.[66]

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 1.2 GW. Five sites were withdrawn, including the Shell Flat site off the coast of Lancashire.[67]

Four offshore wind farms are in the Thames Estuary area: Kentish Flats, Gunfleet Sands, Thanet and London Array. The latter was the largest in the world from April 2013 to September 2018.

Delivery of UK's longest onshore turbine blades. 58.7m blades for 145m GE 2.75–120 wind turbines at Muirhall Wind Farm.[68]

Lessons learnt from Round 1, particularly the difficulty in getting planning consent for offshore wind farms, together with the increasing pressure to reduce CO₂ 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 13 km 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 Round 2. The results were announced in December 2003 with 15 projects awarded with a combined power generating capacity of 7.2 GW. By far the largest of these is the 900 MW Triton Knoll.[69] 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.[67]

Scroby Sands wind farm from Great Yarmouth

In May 2010, the Crown Estate gave approval for seven Round 1 and 2 sites to be extended creating an additional 2 GW of offshore wind capacity.[70] Each wind farm extension will require a complete new planning application including an Environmental Impact Assessment and full consultation. The sites are:[71]

• 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.

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; Round 3 was on a much bigger scale than the combined total of its predecessors (Rounds 1 and 2 allocated 8 GW of sites, while Round 3 alone could identify up to 25 GW).

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 40 applications 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).

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:[72]

In 2009, during the Round 3 initial proposal stage 26.7 GW 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 was announced in 2019 and represented the first large scale new leasing round in a decade. This offers the opportunity for up to 7 GW of new offshore capacity to be developed in the waters around England and Wales.[79] This is split into four bidding areas:

• Dogger Bank
• Eastern Regions
• South East
• Northern Wales and Irish Sea

The tenders are under review and the Agreements for Lease will be announced in Autumn 2021. In February 2021, four winners for almost 8 GW were found, mostly new entries. Option fees were introduced this time, with clearing prices ranging from £76,203 (US$105,022) per megawatt year to £154,000 (US$212,241) for sites ranging from 480 MW to 1.5 GW. The Crown Estate will be collecting annual revenues of around £880 million until the sites reach FID or for a maximum of 10 years.[80][81]

The UK has accelerated its decommissioning of coal power stations aiming for a 2024 phase-out date,[82] and recent British nuclear power stations have encountered significant technical issues and project overruns that have resulted in significant increases in project costs.[83] These issues have resulted in new UK nuclear projects failing to secure project financing. Similarly, SMR technology is not currently economically competitive with offshore wind in the UK. Following the Fukushima nuclear disaster public support for new nuclear has fallen.[84] In response, the UK government increased its previous commitment for 40 GW of Offshore wind capacity by 2030.[85] As of 2020, this represents a 355% increase over current capacity in 10 years. It is expected the Crown Estate will announce multiple new leasing Rounds and increases to existing bidding areas throughout the 2020–2030 period to achieve the government's aim of 40 GW.

In addition to the 25 GW scoped under the Round 3 SEA, the Scottish Government and the Crown Estate also called for bids on potential sites within Scottish territorial waters. These were originally considered as too deep to provide viable sites, but 17 companies submitted tenders and the Crown Estate initially signed exclusivity agreements with 9 companies for 6 GW worth of sites. Following publication of the Scottish Government's sectoral marine plan for offshore wind energy in Scottish territorial waters in March 2010,[86] six sites were given approval subject to securing detailed consent. Subsequently, 4 sites have been granted agreements for lease.[87]

The complete list of sites including power updates and developer name changes:

In 2022 Crown Estate announced the outcome of its application process for ScotWind Leasing, the first Scottish offshore wind leasing round in over a decade and the first ever since the management of offshore wind rights were devolved to Scotland. 17 projects were selected with a capacity of 25 GW.

Specialist trailers deliver turbine components to Dorenell Wind Farm.[214]

Turbine blade convoy for Scout Moor Wind Farm passing through Edenfield.

Hafoty Sion Llwyd, on the shore of Llyn Brenig

The Ardrossan Wind Farm in North Ayrshire, Scotland

The first commercial wind farm was built in 1991 at Delabole in Cornwall;[215] it consisted of 10 turbines each with a capacity to generate a maximum of 400 kW. Following this, the early 1990s saw a small but steady growth with half a dozen farms becoming operational each year; the larger wind farms tended to be built on the hills of Wales, examples being Rhyd-y-Groes, Llandinam, Bryn Titli and Carno. Smaller farms were also appearing on the hills and moors of Northern Ireland and England. The end of 1995 saw the first commercial wind farm in Scotland go into operation at Hagshaw Hill. The late 1990s saw sustained growth as the industry matured. In 2000, the first turbines capable of generating more than 1 MW were installed and the pace of growth started to accelerate as the larger power companies like Scottish Power and Scottish & Southern became increasingly involved in order to meet legal requirements to generate a certain amount of electricity using renewable means (see Renewables obligations below). Wind turbine development continued rapidly and by the mid-2000s 2 MW+ turbines were the norm. In 2007, the German wind turbine producer Enercon installed the first 6 MW model ("E-126"); The nameplate capacity was changed from 6 MW to 7 MW after technical revisions were performed in 2009 and to 7.5 MW in 2010.

Growth continued with bigger farms and larger, more efficient turbines sitting on taller and taller masts. Scotland's sparsely populated, hilly and windy countryside became a popular area for developers and the United Kingdom's first 100 MW+ farm went operational in 2006 at Hadyard Hill in South Ayrshire.[216] 2006 also saw the first use of the 3 MW turbine. In 2008, the largest onshore wind farm in England was completed on Scout Moor[217] and the repowering of the Slieve Rushen Wind Farm created the largest farm in Northern Ireland.[218] In 2009, the largest wind farm in the United Kingdom went live at Whitelee on Eaglesham Moor in Scotland.[219] This is a 539 MW wind farm consisting of 215 turbines. Approval has been granted to build several more 100 MW+ wind farms on hills in Scotland and will feature 3.6 MW turbines.

As of September 2013, there were 458 operational onshore wind farms in the United Kingdom with a total of 6565 MW of nameplate capacity. A further 1564 MW of capacity is currently being constructed, while another 4.8 GW of schemes have planning consent.[23]

In 2009, United Kingdom onshore wind farms generated 7,564 GW·h of electricity; this represents a 2% contribution to the total United Kingdom electricity generation (378.5 TW·h).[220]

Large onshore wind farms are usually directly connected to the National Grid, but smaller wind farms are connected to a regional distribution network, termed "embedded generation". In 2009 nearly half of wind generation capacity was embedded generation, but this is expected to reduce in future years as larger wind farms are built.[221]

Gaining planning permission for onshore wind farms continues to prove difficult, with many schemes stalled in the planning system and a high rate of refusal.[222][223] The RenewableUK (formerly BWEA) figures show that there are approximately 7,000 MW worth of onshore schemes waiting for planning permission. On average, a wind farm planning application takes two years to be considered by a local authority, with an approval rate of 40%. This compares extremely unfavourably with other types of major applications, such as housing, retail outlets and roads, 70% of which are decided within the 13- to 16-week statutory deadline; for wind farms the rate is just 6%. Approximately half of all wind farm planning applications, over 4 GW worth of schemes, have objections from airports and traffic control on account of their impact on radar. In 2008 NATS en Route, the BWEA, the Ministry of Defence and other government departments signed a Memorandum of Understanding seeking to establish a mechanism for resolving objections and funding for more technical research.

Wind farms in the UK often have to meet a maximum height limit of 125 m (410 ft) (excluding Scotland). However, modern lower cost wind turbines installed on the continent are over 200 m (660 ft) tall.[224] This planning criteria has stunted the development of onshore wind in the UK.

From 2002 to 2015, windfarms were subsidised through the Renewables Obligation where British electricity suppliers were required by law to provide a proportion of their sales from renewable sources such as wind power or pay a penalty fee. The supplier then received Renewable Obligation Certificates (ROC) for each MW·h of electricity they have purchased.[251] The Energy Act 2008 introduced banded ROCs for different technologies from April 2009. Onshore wind receives 1 ROC per MWh, but since the Renewables Obligation Banding Review in 2009, offshore wind has received 2 ROCs to reflect its higher costs of generation.[252] In Northern Ireland, a banding of 4 ROCs is available for small onshore turbines.[253]

Wind energy received approximately 40% of the total revenue generated by the Renewables Obligation,[254] and ROCs provided over half of the revenue of the wind farms involved.[255] The total annual cost of the Renewables Obligation reached £6.3 billion in 2019–20, of which 67% was for wind power.[256] This cost was added to end-user electricity bills. Sir David King warned that this could increase UK levels of fuel poverty.[257]

The government closed the Renewables Obligation to new onshore wind power projects in 2016.[258] Support for offshore wind was moved into the government's Contract for Difference (CfD) regime.[259] Support for wind power under this programme rose to £1.7 billion in 2020, with £1.6 billion of that total shared between six offshore windfarms.[260]

In 2023 there is an effective windfall tax.[261][262]

The economics of wind power are driven by factors such as the capital, operating and finance costs, as well as the operational performance or capacity factor. These factors are in turn affected by issues such as location, turbine size and spacing and, for offshore windfarms, water depth and distance from shore. Operating costs and performance change over a windfarm's life, and several years of data are required before an assessment of the trajectory of these figures can be made.[263]

A review of financial accounts published by the Renewable Energy Foundation in 2020 showed that UK offshore windfarm capital costs rose steadily from 2002 to around 2013, before stabilising and perhaps falling slightly.[263] Operating costs have risen steadily up to the time of the study, but financing costs have fallen. This picture has been confirmed by a comprehensive review of audited accounts data for UK offshore windfarms, which found that levelised costs rose from around £60–70/MWh for early projects, to around £140–160/MWh by 2010–13, before stabilising.[264]

The Renewable Energy Foundation study also examined onshore wind costs, finding that capital costs had risen to around 2011 before declining slightly thereafter, while operating costs had risen steadily.[263] Estimates of the levelised cost of UK onshore wind are older. A 2011 study by the engineering consultancy Mott MacDonald put onshore wind costs at £83/MWh, below new nuclear at £96/MWh.[265]

In the UK's contract for difference auctions of 2017 and 2019, offshore windfarms made bids to supply the grid at strike prices much lower than anything seen before: £57.50/MWh in the 2017 auction[266] and £39.65/MWh in the 2019 one.[267] These values are below the ostensible windfarm costs outlined in the previous section, and have therefore been widely taken as evidence of a fundamental change in the economics of offshore wind power; in other words that technological advances have led to much lower costs.

There has been no similar reduction in bidding prices from onshore windfarms. The lowest successful bid under the CfD regime has been £79.99/MWh.[268]

The building of UK wind farms has been supported through the Renewables Obligation and, since 2016, by price guarantee support through the Contracts for Difference regime too. The 2018 levelised cost of electricity (LCOE) of offshore wind was in the range £100–150/MWh.[264] However, in recent CfD auctions, strike prices as low as £39.65/MWh have been agreed for offshore wind projects, which has led to an assumption that there has been an equivalent reduction in the underlying costs.[269][270] Due to the structure of the contract for difference arrangements wind generators pay the government when power prices exceed the strike price.[271] Wholesale power prices averaged £57/MWh in 2018 and £113/MWh in 2021 before spiking above £400/MWh in 2022.[272]

Offshore wind has historically been more expensive than onshore wind, but in 2016 it was predicted that it would have the lowest levelised cost of electricity in the United Kingdom in 2020 when a carbon cost was applied to generating technologies.[273]^: p25 In the 2022 AR4 CFD auction, offshore wind cleared at an average price of £37.35/MWh versus onshore winds average price of £42.47/MWh (both 2012 prices).[274]

Historically, wind power had raised costs of electricity slightly. In 2015, it was estimated that the use of wind power in the UK had added £18 to the average yearly electricity bill.[275] This was the additional cost to consumers of using wind to generate about 9.3% of the annual total (see table below) – about £2 for each 1%.

A statistical and econometric analysis of a majority of onshore and offshore windfarms built in the United Kingdom since 2002 with a capacity of more than 10MW has been performed by a former professor of the School of Economics at the University of Edinburgh on behalf of an anti wind power organisation. It finds that the actual cost of onshore and offshore wind generation has not fallen significantly. Rather, capital and operating costs per MW have increased, the latter driven by higher than expected frequency of equipment failure and preventative maintenance associated with new generations of larger turbines. The study concludes that, after current contracts guaranteeing above-market prices expire, expected revenues from generation will be less than operating cost. If confirmed, this would require financial regulators to impose heavy risk weightings on loans to offshore wind farm operators, effectively making them too risky for pension funds and small investors.[276]

The development of the GB grid was characterised by the close proximity of major sources and demand for electricity. Since wind farms tend to be sited far from centres of demand, transmission capacity can be inadequate to deliver electricity to users, particularly when wind speeds are high. When the grid cannot deliver electricity generated, wind farm operators are paid to switch off. It is normally necessary to pay another generator – normally a gas-fired power station – on the other side of the constraint to switch on as well, to ensure that demand is met. These two incentives are referred to as "constraint payments"[289] or curtailment,[288] and they are one source of criticism of the use of wind power and its implementation; in 2011 it was estimated that nearly £10 million in constraint payments would be received, representing ten times the value of the potential lost electricity generation.[290] Wind farm constraint payments have increased substantially year on year, £224 million, out of a total of £409 million in 2020–21.[291] In addition, £582 million was spent rebalancing the system afterwards, mainly to gas-fired power stations.[288]

There is some dispute over the necessary amount of reserve or backup required to support the large-scale use of wind and solar energy due to the variable nature of its supply. In a 2008 submission to the House of Lords Economic Affairs Committee, E.ON UK argued that it is necessary to have up to 80–90% backup.[292] Other studies give a requirement of 15% to 22% of installed intermittent capacity.[280] National Grid, which has responsibility for balancing the grid, reported in June 2009 that the electricity distribution grid could cope with on-off wind energy without spending a lot on backup, but only by rationing electricity at peak times using a so-called "smart grid", developing increased energy storage technology and increasing interconnection with the rest of Europe.[293][294] In June 2011, several energy companies including Centrica told the government that 17 gas-fired plants costing £10 billion would be needed by 2020 to act as back-up generation for wind. However, as they would be standing idle for much of the time they would require "capacity payments" to make the investment economic, on top of the subsidies already paid for wind. In 2015–2016, National Grid contracted 10 coal and gas-fired plants to keep spare capacity on standby for all generation modes, at a cost of £122 million, which represented 0.3% of an average electricity bill.[295]

Grid scale battery storage is being developed in order to cope with the variability in wind and solar power. As of May 2021, 1.3 GW of grid storage batteries was active,[296][297] along with the traditional 2.5 GW of pumped storage at Dinorwig, Cruachan and Ffestiniog.

With the increase in proportion of energy being generated by wind and solar on the UK grid, there is a significant reduction in synchronous generation. Therefore, in order to ensure grid stability, the National grid ESO is piloting a range of demand side and supply side frequency response products.[298]

Wind power is Scotland's fastest growing renewable energy technology, with 5328 MW of installed capacity as of March 2015. This includes 5131 MW of onshore wind and 197 MW of offshore wind.[338]

Whitelee Wind Farm near Eaglesham, East Renfrewshire is the largest onshore wind farm in the United Kingdom with 215 Siemens and Alstom wind turbines and a total capacity of 539 MW.[339] Clyde Wind Farm near Abington, South Lanarkshire is the UK's second largest onshore wind farm comprising 152 turbines with a total installed capacity of 350 MW.[340] There are many other large onshore wind farms in Scotland, at various stages of development, including some that are in community ownership.

Robin Rigg Wind Farm in the Solway Firth is Scotland's only commercial-scale, operational offshore wind farm. Completed in 2010, the farm comprises 60 Vestas turbines with a total installed capacity of 180 MW.[341] Scotland is also home to two offshore wind demonstration projects: The two turbine, 10 MW Beatrice Demonstrator Project located in the Moray Firth, has led to construction of the 84 turbine, 588MW Beatrice Wind Farm set to begin in 2017 and the single turbine, 7 MW Fife Energy Park Offshore Demonstration Wind Turbine in the Firth of Forth. There are also several other commercial-scale and demonstration projects in the planning stages.[342]

The siting of turbines is often an issue, but multiple surveys have shown high local community acceptance for wind power in Scotland.[343][344][345] There is further potential for expansion, especially offshore given the high average wind speeds, and a number of large offshore wind farms are planned.

The Scottish Government has achieved its target of generating 50% of Scotland's electricity from renewable energy by 2015, and is hoping to achieve 100% by 2020. Renewables produced 97.4% of Scotland's net electricity in 2020, mostly from wind power.[346]

In July 2017 work commissioning an experimental floating wind farm known as Hywind at Peterhead began. The wind farm is expected to supply power to 20,000 homes. Manufactured by Statoil, the floating turbines can be located in water up to a kilometre deep.[347] In its first two years of operation the facility with five floating wind turbines, giving a total installed capacity of 30 MW, has averaged a capacity factor in excess of 50%[348]

• 
  Whitelee Wind Farm with the Isle of Arran in the background.
• 
  Clyde Wind Farm
• 
  Ardrossan Wind Farm from Portencross, just after sunrise