RWE accuses Iberdrola of hypocrisy in wind theft row
German utility is embroiled in several disputes with Iberdrola's ScottishPower and other developers over wind wakes from projects planned in British waters
RWE has accused Iberdrola of hypocrisy in a wind theft row concerning two UK offshore wind projects, arguing the Spanish utility is adopting “fundamentally contradictory” positions.
RWE claims Iberdrola, through its subsidiary ScottishPower, is demanding mitigation for wake losses it could suffer from while not providing the same for wake losses its own projects could cause.
The German utility raised the argument in the planning proceeding for the up to 1.1GW Five Estuaries offshore wind farm.
RWE owns a 33.3% stake in the project and is leading its development on behalf of the other shareholders, including a consortium led by Australia’s Macquarie, Irish utility ESB and Japan’s Sumitomo Corporation.
Iberdrola has raised concerns about wake losses that East Anglia Two could suffer from Five Estuaries, with the two sites separated by as little as 6km.
What are wind wakes?
When wind turbines extract energy from the wind to produce power, they leave trails of lower intensity and more turbulent wind stretching behind them. These trails, known as wind wakes, can stretch vast distances – even 100km. If one wind farm is caught in the ‘shadow’ of another’s wake, the lower wind speed will mean it generates less power, reducing revenues. One wind farm 'waking' another is sometimes known as ‘wind theft’.
A wake loss assessment carried out for Iberdrola by Norwegian consultancy DNV found that Five Estuaries could cause East Anglia Two wake losses – and an associated drop in annual energy production (AEP) – of between 0.5% and 2.1%.
In light of these predicted losses, Iberdrola is seeking either mitigation or compensation from the RWE project.
But in submissions this month, RWE has accused Iberdrola of double standards, saying it is not aware of any attempt made by East Anglia Two to mitigate or compensate wake losses it will cause the nearby Galloper and Greater Gabbard offshore wind farms.
Five Estuaries is an extension to the 353MW Galloper wind farm, which is also owned by RWE. Next to Galloper is the 504MW Greater Gabbard wind farm, a 50-50 joint venture between RWE and Britain’s SSE.
Iberdrola’s position is “in effect that whilst it was not required to assess the wake effects of its project on other wind farms or to mitigate them for the purposes of its own consenting process,” the Five Estuaries project “is required to do so in the context of its application for development consent,” said RWE.
“Not only is this position fundamentally contradictory,” said RWE, “it would give rise to an unlevel playing field between offshore wind developers and potentially inhibit the delivery of the government’s renewable energy targets.”
This is because it would place Five Estuaries in a “fundamentally disadvantaged position” compared with East Anglia Two, as well as “other developers whose projects have been consented without requiring an assessment of wake effects or implementation of mitigation.”
In its most recent submission published on 11 March, RWE said that Iberdrola “continues to remain silent” on this issue and the “obvious questions of fairness which arise.”
RWE also said it “wishes to stress” that the wake assessment Iberdrola submitted is “based on the incorrect premise that East Anglia Two should be regarded as akin to an existing, operational wind farm with a fixed layout which will inevitably and unavoidably be affected by wake effects” from Five Estuaries.
“As set out above, the East Anglia Two project is in development and has not yet proceeded to offshore construction and it is not therefore appropriate to proceed (as the wake assessment does) on this incorrect premise.”
Another “fundamental deficiency” of the wake loss assessment, said RWE, is that it only considers the effects of the Five Estuaries project on East Anglia Two.
“The assessment wholly fails to identify or take into account effects that the East Anglia Two project will have on Five Estuaries, or effects on the existing operational Galloper and Greater Gabbard wind farms.”