A next-generation wind farm which could power the equivalent of a million homes has been given the green light from government.

At 247 metres high, the 172 turbines on ScottishPower Renewables’ East Anglia Three project will be more than twice the height of Norwich Cathedral which, at 96 metres, is East Anglia’s tallest building.

The project was given planning approval by business secretary Greg Clark and will cover 305 sq km when it is completed 69km off the Norfolk coast.

The project is seen as important in driving down the costs of offshore wind. The company’s East Anglia One scheme is the best-value project to enter UK construction, at £119 per MW/h, with future subsidy auctions expected to drive that price lower.

Keith Anderson, chief executive of ScottishPower Renewables, said: “With the support of a highly-skilled supply chain, East Anglia Three will further enhance the UK’s leading position in offshore wind. No other sector ticks all of the boxes in its ability to support the government’s plans for rebalancing the economy and promoting economic diversity through the Industrial Strategy.”

He added: “Large-scale projects like East Anglia Three will continue to help to encourage economic regeneration where it is needed most.”

ScottishPower Renewables will now enter a Contract for Difference auction process where the most economical projects are funded for their investment in low-carbon energy generation.

If the bid is successful, construction will begin around 2022 and be operational by 2025.

In total, East Anglia Three will require four offshore collector stations and two converter station platforms, and possibly an accommodation platform.

Cables will run between the turbines and those platforms, with up to four cables bringing the power to shore, and four connecting the two East Anglia array wind farms.

Landfall will be at Bawdsey, from where up to four underground cables will be laid through East Anglia One ducting, running 37km to a transformer substation in Bramford in Suffolk, where the wind farm is connected to the National Grid. The 714MW-capacity East Anglia One is due to be fully operational in 2020, one of four projects being developed by ScottishPower Renewables