The aim of this guide is to help develop a greater understanding of the components and processes involved in the development of UK offshore wind farms that will be built up to 2025.
More explanation of content is provided in Interactive guide.
To supplement what is in the guide in PDF format, we have added photographs and a range of other information relevant to the UK industry.
BVG Associates is grateful to the following companies for their help in compiling the PDF guide:
DEME Group, GE Renewable Energy, Fugro, Generating Better, Innogy, JDR Cable Systems, MHI Vestas Offshore Wind, Natural Power (Fred. Olsen), Oldbaum Services, Ørsted, Senvion, Siemens Gamesa Renewable Energy, Siemens Power Transmission and Distribution, SNC-Lavalin - Atkins, Vattenfall
The UK's first demonstration offshore wind farm was installed in December 2000 off the Northumberland coast. It consists of two 2MW Vestas wind turbines with a rotor diameter of 66m, on monopile foundations in about 10m water, less than 2km from shore.
At the time, these were the largest turbines installed offshore in the world. At the same time, the first applications (Round 1) for sea bed leases were presented to The Crown Estate, the landlord for the sea bed within UK waters.
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North Hoyle, the UK's first commercial wind farm was installed off the North Wales coast. It consists of thirty 2MW Vestas turbines with a rotor diameter of 80m, on monopile foundations in about 12m water, about 8km from shore.
Other Round 1 projects followed soon after, though the last of 12 projects were only installed in 2013, bringing the total Round 1 capacity to 1.2GW. Five projects were withdrawn based on environmental grounds.
In 2003, Narec (now part of the Offshore Renewable Energy (ORE) Catapult), was set up in Blyth to support the development of renewable energy by providing world-class test and other technical services.
At the end of 2003, the results of Round 2 of sea bed leasing were announced, with 15 projects awarded a total of 7.2GW capacity.
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Burbo Bank was the first UK offshore wind farm where 100m rotor diameter turbines were installed. It consists of 25 3.6MW Siemens turbines with a rotor diameter of 107m, installed off Liverpool.
At the same time, two 5MW Senvion turbines with a rotor diameter of 126m were installed in the Moray Firth, Scotland, on the first jacket foundations installed in offshore wind, globally.
In 2007, the Government announced a strategic environmental assessment as an early step to Round 3 of sea bed leasing by The Crown Estate. The third sea bed leasing round was subsequently launched by The Crown Estate in 2008, offering nine large zones with a capacity of around 30GW.
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In 2009, the first 100MW project started operation off the Lincolnshire coast, when the twin projects Lynn and Inner Dowsing were commissioned. The single construction project consists of 54 3.6MW Siemens turbines, totalling 194MW.
UK installations pushed the UK past Denmark to take over as the global lead for offshore wind installed capacity.
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Thanet, in the Southern North Sea, became the world's largest offshore wind project and the first to have 100 turbines. It consists of 100 3MW Vestas turbines, located in water depths up to 23m, about 12km from shore.
At the same time, the winners of The Crown Estate's Round 3 leasing competition were announced, the largest with capacity up to 10GW.
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Greater Gabbard, the UK's first 500MW project started operation. It consists of 140 3.6MW Siemens turbines and became the world's largest offshore wind farm.
In 2012, The Crown Estate also published its flagship industry report on the potential for cost of energy reduction in offshore wind to 2020. Coupled with the output the Offshore Wind Cost Reduction Task Force, this set the direction of Government-industry collaboration in offshore wind for the next six years.
It was also the year that the ORE Catapult was established in Glasgow to lead technology innovation and research centre for offshore wind, wave and tidal energy.
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The first 7MW turbine was constructed offshore in the Firth of Forth, Scotland. The prototype turbine, developed by Samsung, has a rotor diameter 171m. This turbine is now operated by ORE Catapult.
At the same time, the first 6MW direct-drive (gearless) Siemens offshore wind turbines were installed at Gunfleet Sands in the Thames Estuary. Historically, gearboxes have been a source of unreliability and OPEX for wind turbines, but removing them drives a significant increase in size and cost of the generator. Some other suppliers, such as MHI Vestas, have opted for a mid-speed generator with a simplified gearbox as a solution.
London Array, at 630MW, took over as the world's largest wind farm, consisting of 175 3.6MW Siemens turbines.
The Government also announced an intermediate step to a new auction market mechanism for offshore wind, Contracts for Difference (CfD) as part of Electricity Market Reform. This step, known as Final Investment Decision (FID) Enabling for Renewables, led eventually to a range of offshore wind projects obtaining strike prices of £140 to £155/MWh for projects delivered up to 2019.
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The first CfD auction results for UK offshore wind were announced, with strike prices of £114 to £120/MWh (2012 prices) for projects to be delivered by 2019.
In 2014, Mitsubishi Heavy Industries, Ltd. the Japanese multinational engineering, electrical equipment and electronics company and wind turbine supplier Vestas established a 50:50 joint venture for supply to the offshore wind industry, MHI Vestas Offshore Wind.
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Seven years after obtaining an agreement for lease, the first wind farm from the UK leasing Round 3 started operation (although it was not fully commissioned until 2018). Rampion, in the English Channel, consists of 130 3.45MW turbines from MHI Vestas Offshore Wind.
At the same time, the world's first commercial floating offshore wind farm Hywind Scotland started operation. The five 6MW Siemens turbines were installed on spar-buoy foundations in water about 100m deep off Peterhead in Grampian, Scotland.
The second CfD auction results for UK offshore wind were announced, with strike prices of £57 to £75/MWh (2012 prices) for projects to be delivered by 2023, showing a substantial cost of energy reduction since the previous auction.
German conglomerate, Siemens, the largest industrial manufacturing company in Europe, merged its wind division with Spanish turbine supplier Gamesa to form Siemens Gamesa Renewable Energy. GE Renewable Energy acquired leading wind turbine blade manufacturer LM Wind Power.
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The first contracts were placed for MHI Vestas Offshore Wind 9.5MW turbines, which will be installed in 2021 and 2022 at the Triton Knoll and Moray East wind farms. Both MHI Vestas Offshore Wind and Siemens Gamesa Renewable Energy have 10MW+ turbines and GE Renewable Energy announced its 12MW+ turbine with a 220m diameter rotor.
At the same time, the record for the largest offshore wind farm was broken, with the 659MW Walney Extension project in Morecambe Bay, consisting of 40 MHI Vestas Offshore Wind 8.25MW turbines and 47 Siemens Gamesa Renewable Energy 7MW turbines.
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The 1,218MW Hornsea One wind farm began operation becoming the world's largest offshore wind farm. It consists of 174 Siemens Gamesa Renewable Energy 7MW turbines and is almost double the capacity of the previous largest offshore wind farm.
The third CfD auction resulted in record low prices for offshore wind, awarding strike prices (at 2012 prices) of £39.65/MWh and £41.61/MWh for projects commissioned in 2023/2024 and 2024/2025 respectively. Projects in what was the Dogger Bank Round 3 Zone were awarded CfDs for a total of 4.8GW.
Following the CfD auction results, it was announced that two projects would be built without a CfD.
These were the East Anglia THREE project (that will now be built alongside East Anglia ONE North and TWO projects as one large project called the East Anglia Hub) and an additional part of the Seagreen Phase 1 project.
The first offshore wind project in the UK was decommissioned. The 4MW Blyth Offshore Wind farm had been commissioned in 2000.
In 2019 the UK Government and the Offshore Wind Industry Council signed a Sector Deal for offshore wind in the UK. The deal included a number of targets for the industry including a target of 30GW of installed capacity by 2030, which has since been increased to 40GW.
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There was only one offshore wind project installed in the UK during 2020, the 714MW East Anglia ONE project which was fully commissioned in July 2020. Offshore construction began for the Triton Knoll and Neart na Gaoithe projects. Onshore construction started for the Dogger Bank A and B projects, which also reached FID. The projects will have a combined installed capacity of 2.4GW. Dogger Bank A and B will also use GE Renewable Energy’s 13MW Haliade-X turbine, the first time turbines of this size have been contracted.
New lease competitions run by The Crown Estate and Crown Estate Scotland were delayed, including by COVID-19.
SGRE also announced its latest offshore turbine rated at 14MW with a rotor diameter of 222m. The turbine will first be installed on commercial projects in 2024.
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The Crown Estate allocated areas for nearly 8GW of offshore wind capacity in the Offshore Wind Leasing Round 4 in 2021. The six winning bids will pay a combined £879 million every year throughout the development phase in option fees. The Crown Estate also announced its plans to lease up to 4GW floating offshore wind in the Celtic Sea.
The first round of offshore wind leasing in Scottish waters for over a decade, ScotWind, was launched in July 2021, with water depths suitable for bottom-fixed and floating offshore wind.
The UK Government also launched the fourth CfD allocation round with a pot of £200 million allocated for offshore wind, and an additional £24 million ringfenced specifically for floating offshore wind. It also announced that CfD auctions will be conducted annually from 2023 onwards to increase the rate of installations.
The largest floating offshore windfarm to date, Kincardine Offshore Windfarm, was fully commissioned in October 2021 with an installed capacity of 50MW.
The Hornsea 2 project generated its first power in December 2021. Once completed, the 1.3GW windfarm will overtake Hornsea 1 as the largest offshore wind farm in the world. It is expected to become fully operational in 2022.
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