Electricity is the main energy source used to produce aluminum through the process of electrolysis. The hydroelectricity consumed by our Québec smelters is, of course, a renewable energy source. Our plants also use some fossil fuels (see graph above). Electricity consumption per tonne of aluminum produced is higher at the Baie-Comeau Smelter due to the less efficient Söderberg technology. In 2012, there was a slight increase in the amount of energy consumed per tonne of aluminum produced.