Total GHG emissions from Australia’s seven alumina refineries were 6 per cent lower in 2011, largely on the back of reduced production levels. 13.9 million tonnes of CO2-e were emitted in 2011, compared with 14.9 Mt in 2010 and 14.4 in 2009. Absolute emissions from Australia’s alumina refineries have increased by 30 per cent since 1990, despite a 75 per cent increase in production over this period.
Aggregated per unit emissions were 0.71 tonnes of CO2-e per tonne of alumina in 2011, 3 per cent lower than in 2010 and 26 per cent lower than the 1990 value of 0.96 tonnes of CO2-e per tonne of alumina. This result matches our industry’s record low emissions intensity of 0.71 per tonne of alumina first achieved in 2009.
The continuing strong performance of Australia’s alumina refineries in terms of emissions reduction is a reflection of the increased uptake of natural gas as a fuel source, mainly in the form of cogeneration – which offers superior levels of thermal efficiency through the provision of heat, steam and electricity for the process.