The world’s largest offshore wind farm is set to open in British waters today and will generate enough electricity to power 600,000 homes.

Operated by Denmark’s wind power giant Ørsted, the Walney wind farm off the coast of Cumbria has grown to the size of 20,000 football pitches following an extension, which catapults the project above the size of the giant London Array in the Thames Estuary.

The extension project uses a new generation of super-sized wind turbines, each standing around 520 feet high, to generate around 660MW.

Together with Ørsted’s earlier Walney 1 and Walney 2 wind projects, the stretch of sea off the Cumbrian coast will have a power capacity of 1.5GW - enough to keep the lights on in 1.2 million homes.

Matthew Wright, Ørsted’s UK boss, said the extension project “showcases the industry’s incredible success story”.

The UK is the world leader in offshore wind and has played host to the industry’s staggering fall in costs in recent years.