April 19, 2024

Harnessing UK's offshore wind potential

by Neil Beardsmore

The gust of wind in the UK is moving more than sailboats. It is electrifying.

Europe’s windiest country is right on course to meet its clean energy targets of 15 percent by 2020 (Ashworth-Hayes, 2015). Not just a gust of hot air, wind power generation is growing from strength to strength, serving over 30 percent of British homes in 2015 (Murray, 2015).

In 2009, the UK made a commitment to the European Union to have renewable sources account for 15 percent of its energy consumption (OJEU, 2009). The definition of energy consumption includes the supply of heating and transportation. To achieve this overall target, Britain plans to have 12 percent of its heating, 10 percent of its transportation and 30 percent of electricity generation derived from renewable sources (Ashworth-Hayes, 2015). Renewable energy met over 18 percent of UK’s electricity needs in 2015 approximately three percent more than it did two years before (Cuff, 2015).

Last year, UK’s Energy Secretary, Amber Rudd proposed plans to shut all remaining coal-fired power plants that are unable to install carbon capture and storage facilities by 2025 (BBC, 2015). To compensate for this loss of capacity, plans were set in place to substitute it with more carbon friendly gas-fired power plants and renewable energy sources.

Although gas power was UK’s main source of electricity generation, it is widely recognised across the energy industry, that renewable energy, in particular, wind, is an important part of the energy mix.

The force of the wind has been pushing its way ahead to meet the challenge to provide clean, affordable energy to British households. Just last year, 11 percent of UK’s overall power supply was generated by wind power, a one and a half percent jump from the year before (Cuff, 2015). Equivalent to over 34 terawatt hours (TWh), that is enough power to electrify over eight million homes (RUK, 2016a). Whilst onshore wind technology is more established, wind farms are being increasingly developed offshore, where they can harness stronger, more persistent winds (Gridtech, 2012).

Milking UK’s offshore wind farms
The British government looks set to provide support for offshore wind as a renewable resource. Last year, 17 wind projects were awarded Contracts for Difference (CfD) subsidies, the government’s quest to support for renewable energy development (Weston, 2015). Only two of those projects were offshore wind farms. However, the investment towards wind energy, in particular offshore wind, is clear. Three CfD auctions are on the slate before 2020 – with offshore wind set to take centre stage (BVC Associates, 2016; Stoker, 2015).

In 2015 it is estimated that offshore wind contributed 18 percent of total renewable energy generation in the UK, which is roughly 5GW in production capacity (RUK, 2016b). This translates to approximately 15 TWh, which is equivalent to the electricity consumption of three and a half million homes (RUK, 2016b). The UK has the largest market of offshore wind in the world. It accounts for over half of the global wind offshore capacity followed by Denmark and Germany (Hill, 2015). As a result, offshore wind production in the UK is expected to double in 2020, reaching above 10GW, supplying between eight to 10 percent of UK’s annual electricity demands. Global Data estimates that this will amount to over 23 GW by 2025 (Hill, 2015).

Currently the UK has consented to the development of 11 offshore wind farms, with a total capacity exceeding 11 MW (RUK, 2016c). One of the projects consented, and currently under construction, is Galloper Wind Farm Limited (GWFL).

Galloper Wind Farm Limited (GWFL)
Galloper Offshore Wind Farm, located off the coast of Suffolk, is an extension of the existing and fully operational 504 MW Greater Gabbard Wind Farm. The project was originally a 50/50 partnership between Scottish & Southern Energy (SSE) and RWE Innogy, with development of the project led by RWE Innogy. Following Financial Close of the project in October 2015 a new joint equity partnership between RWE Innogy, UK Green Investment Bank, Siemens Financial Services and Macquarie Capital was announced. At the same time 13 new financial backers were confirmed. The successful completion of the finance and project partnerships secured the future of the £1.5 billion offshore project, leading GWFL to be named as European Power Deal of the Year in Project Finance International (PFI) Yearbook and Top Deal of 2015 by Infranews.

The project, which has grid connection secured, is being progressed under the Renewables Obligation support scheme and RWE Innogy will continue to lead the development and construction of it. Initial onshore enabling works were carried out in 2014 and construction work recommenced following Financial Close in November 2015. The wind farm, which will comprise 56, six megawatt turbines, is expected to commence operations by March 2018.

Upon completion Galloper will be able to generate up to 336 megawatts of energy, equivalent to the approximate domestic needs of around 336,000 average UK households. Up to eight hundred jobs are expected to be created as a result of the construction and operation of the project.

Picking the right partners
With so much at stake, it is essential that the right partners are appointed for the execution of the project. From the turbines to the electrical systems and cabling, it was important for RWE to ensure that the right suppliers were engaged for the Galloper Wind Farm.

The teaming up of GE’s Grid Solutions an Alstom and GE joint venture that brought together over 200 years of experience in advanced energy solutions with Petrofac, an oilfield service company with 34 years of experience made the ideal alliance to supply Galloper’s turnkey power system.

With the oilfield experience Petrofac brings to the table its offshore expertise, tapping on its core strength in foundation design, fabrication and transportation and installation of the offshore substation as well as the logistics to support hook up and commissioning.

In return, GE’s team of specialists will provide overall electrical system design, along with the onshore and offshore substation equipment including all related power transformers and gas insulated switchgear at 132kV and 33kV. Apart from that GE will supply two Static VAr Compensators, each connected to the grid by its own power transformer. This will provide dynamic voltage support to ensure grid code compliance, a stabilized power supply and strengthened transmission grid to ensure efficient connection of the new wind farm to the British transmission system. Incorporated into the scope of work are protection and control systems for the safe operation of the wind farm, including the telecommunications that is required between the onshore and offshore substations as well as the wider network. GE will also supply all ancillary and supporting electrical equipment such as auxiliary and earthing transformers, battery systems, back-up generators and low voltage systems.

This equal collaboration, where both parties are mutually invested, means that the success of project becomes a joint effort. Both Petrofac and GE bring valuable experience and expertise for the successful completion of the Galloper Wind Farm.

The future of offshore wind
With an 18 GW target installation capacity by 2020, the UK government is keen to back offshore wind energy projects (Hill, 2015). The development and investment costs of offshore wind farms are comparatively higher than onshore wind farms. However, in the long term, offshore wind farms have a lower generation cost due to the more powerful winds as well as the lower visual impact of the large wind turbines.

Several major wind operators have stated commitments to develop offshore wind farms in the UK. Dong Energy, UK’s largest operator of offshore wind farms has committed to invest an additional £6 billion in projects by 2020 (Macalister, 2015). The company aims to proceed with the 1.2 GW Hornsea Project One. With 240 five-eight MW turbines installed off the Yorkshire coast, it is set to be the world’s biggest offshore wind farm upon completion in 2020 (Dong Energy 2016). In the same breath, Scottish Power reaffirmed its decision to go ahead with the £2.5 billion investment into East Anglia One, one of UK’s largest offshore wind farms in the North Sea (Hirtenstein, 2016).

The success of these projects largely relies on the availability of government subsidies, in order to allay the initial cost of construction. According to the telegraph.uk, the Hornsea Project One is expected to require £4.2 billion in subsidies over a 15 year period (Gosden, 2016). Underlying the need for subsidies is the ability of operators to keep development costs down. The right synergies and capabilities with the right partners have the potential to create the right conditions to harness the power of the wind in the middle of the big blue sea.

About the Author

Neil Beardsmore is the North Europe Commercial Solutions Leader for GE’s Grid Solutions. Prior to his role with GE, Neil worked for the National Coal Board (now British Coal) where he trained and achieved qualifications as an electrical engineer. After having several key positions in engineering – including the lead engineer for a British funded project in Indonesia – Neil moved to GECALSTHOM where he worked as an HV Systems Development Application Engineer, and later the Operations Manager for distribution projects and the development and execution of projects for rail, industry and utilities.


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