Energy secretary Ed Davey used the announcement to hail a bumper day for British wind power, also flagging-up progress on Vattenfall's 299MW Pen y Cymoedd onshore project.
The 288-turbine Triton Knoll project will cost £3.6bn to develop 32km off the coast of Lincolnshire, in eastern England.
The German utility welcomed the news, but added now-familiar caveats about ongoing UK government commitment to renewables.
Triton
