The UK Secretary of State for Energy and Climate Change Chris Huhne has opened the Delabole wind farm in north Cornwall following upgrades at the site.
Work on the farm covered replacement of ten original turbines and added four more powerful turbines.
The new turbines will have a total capacity of 9.2MW, which will serve energy requirements for up to 7,000 homes, more than double the previous output.
Delabole is the first commercial wind farm in the UK.
Huhne said, "All too often, local communities can see the wind farms but not the windfall. Wind is an abundant, clean, home-grown alternative to fossil fuels. It can't be blown off course by instability abroad, and so it's vital that we use it for our low carbon, energy security."
The wind farm is fully owned and operated by Good Energy, which has invested £11.8m ($19.07m) in the project.