An extension to Walney offshore wind farm in Cumbria has been given consent by the government.
If built, the development by Dong Energy could triple the size of the current wind farm, already one of the biggest in the world.
The Walney extension would have a capacity of up to 750MW with up to 207 turbines, creating enough electricity to power half a million homes.
Construction would last for four years, between 2016 and 2019.
The site would be located to the North West of Walney I and II offshore wind farms, 19km west of the Cumbrian coast.
For the project to go ahead, developers will need to make a final investment decision.