The Alto Minho Wind Farm has an installed capacity of 240 MW, distributed in five sub-parks, designated by Picos, Alto do Corisco, Santo António, Mendoiro-Bustavade and Picoto-São Silvestre. In the north part of the country, the Alto Minho Wind Farm in the Viana do Castelo district, of Portugal, became fully operational in November 2008. At the time of completion, it was Europe's largest on-shore wind farm. The wind farm consists of 68 Enercon E-82 2MW wind turbines and 52 Enercon E-70 E4 2MW turbines, for a grand total of 240 MW. The wind farm produces 530 GWh annually, avoiding 370,000 tonnes (410,000 tons) of carbon dioxide emissions. On March 2018, Portugal generated more renewable energy than it needed for the first time in at least 40 years. Energy from renewable sources made up 103.6 per cent of mainland electricity consumption, according to data from the country’s power grid operator REN, although fossil fuels were used to occasionally top up the electricity supply.