The London Array offshore wind farm has passed the 5TWh generation mark.
The project became fully operational in 2013 but it started exporting power in 2012.
During that period it generated enough energy to power around 1.2 million UK households and prevented the release of more than two million tonnes of carbon dioxide.
Jonathan Duffy, General Manager of London Array, said: “Although the scale of the wind farm is important, so is its performance. Intelligent and targeted maintenance are the keys to ensuring the turbines to be available to capitalise on the wind and to produce power efficiently.”