During 2015, 40.4 TW·h of energy was generated by wind power and the quarterly generation record was set in the three-month period from October to December 2015, with 13% of the nation's electricity demand met by wind. 2015 saw 1.2 GW of new wind power capacity brought online, a 9.6% increase of the total UK installed capacity. Three large offshore wind farms came on stream in 2015, Gwynt y Môr (576 MW max. capacity), Humber Gateway (219 MW) and Westermost Rough (210 MW).