British Energy Secretary Ed Davey signed off on plans to add up to 17 turbines to the Kentish Flats offshore wind farm.
Swedish power company Vattenfall in 2010 unveiled plans to extend the offshore facility by 10-17 turbines. The extension would generate at least 90,000 megawatt hours of electricity per year, enough to meet the annual electricity demands of 20,000 households.
Completed off the eastern coast of Kent in 2005, the wind farm became one of the first for the country's emerging renewable energy sector.
"As well as providing large amounts of clean energy, offshore wind will support jobs and generate major investment up and down the country," Davey said in a statement. "Vattenfall's decision to extend an existing project reflects the ongoing attractiveness of the U.K. as a place to do business in renewable energy."
Davey said London remains committed to a goal of getting 30 percent of the country's electricity generated by renewable resources by 2020.