Two offshore wind farms which could generate enough electricity to power almost three quarters of a million homes have been given the go-ahead by the Government.
But a third project was turned down because of concerns over the impact it could have on seabirds protected by environmental legislation.
The two approved wind farms at Race Bank and Dudgeon in the Greater Wash off the Norfolk coast will have a combined capacity of over 1 gigawatt, potentially generating enough electricity to power 730,000 homes.
The Department of Energy and Climate Change (Decc) said the projects represented around £3 billion of investment.
Docking Shoal wind farm, also off the Norfolk coast, was not given the go-ahead because of the potential impact on Sandwich terns, whose colonies at Blakeney Point and Scolt Head Island fall within a "Special Protected Area", which is protected under EU wildlife laws.
The total amount of offshore wind power now operational, under construction or consented has reached 6.6GW.
Energy Minister Charles Hendry said: "The UK is racing ahead of the global field and these two new offshore wind farms underline this momentum.
"These two projects will not only bring us considerable amounts of clean energy, but significant investment and jobs too.
"We have also shown that we are mindful of other consequences, such as the impact on bird populations, in deciding it would not be appropriate to consent all three applications."
Mark Hanafin, managing director of Centrica Energy which plans to build Race Bank wind farm, said: "Achieving Government consent for Race Bank is an important milestone.
"We will now undertake a thorough appraisal of project costs with a view to making a final investment decision on Race Bank early in 2013."
Centrica said the economics of the project depended on the outcome of the review of renewables subsidies currently being undertaken by the Government.
The company was also behind the failed bid to build a wind farm at Docking Shoal, and warned that the project had accrued considerable costs and had been awaiting planning consent for more than three and half years.
Centrica said the UK needed to maintain an efficient planning process if it was to meet targets to boost renewable energy over the next decade.