The world’s largest offshore windfarm will be officially opened today (6 September) at a ceremony in Cumbria.

The Walney Extension project in the Irish Sea features 47 of MHI Vestas’ 8.25MW V164 turbines and 40 of Siemens Gamesa’s 7MW SWT154 turbines – giving it a total capacity of 659MW. The previous record holder was the 630MW London Array.

The windfarm is jointly owned by the renewable developer Orsted (50 per cent) and the Danish pension funds PKA (25 per cent) and PFA (25 per cent).

The project was awarded a contract for difference at a strike price of £150/MWh (2012 prices) through a one-off non-competitive process prior to the introduction of auctions.

Matthew Wright, managing director for Orsted UK, said: “The UK is the global leader in offshore wind and Walney Extension showcases the industry’s incredible success story.

“The project, completed on time and within budget, also marks another important step towards Orsted’s vision of a world that runs entirely on green energy.”

Energy and clean growth minister Claire Perry, said: “Record-breaking engineering landmarks like this huge offshore windfarm help us consolidate our global leadership position, break records for generating renewable energy, and create thousands of high quality jobs.

“As part of our modern industrial strategy we’ve set out a further £557 million of funding for new renewable projects, helping to tackle climate change and deliver clean growth to local economies.”