The aluminium industry has taken a leadership role by establishing a uniform, quantitative, global approach to energy and greenhouse gas emissions reduction. The industry publishes a complete life cycle inventory report every five years and the results of performance against 13 sustainability indicators annually. Three of these are specifically focused on energy and greenhouse gas emissions reduction in the industry’s production processes:

  1. Following an 86% reduction in its PFC emissions per tonne of primary aluminium produced between 1990 and 2006, the global aluminium industry will further reduce emissions of PFCs by at least 50% by 2020 as compared to 2006, equivalent to a reduction of over 90% compared to 1990.
  2. A 10% reduction in smelter electrical energy usage by IAI member and reporting companies per tonne of aluminium produced by 2010 versus 1990.
  3. A 10% reduction in refinery energy usage by the industry as a whole by 2020 versus 2006.

The primary aluminium industry transforms bauxite ore into metal through the input of energy, in the form of electricity and heat. While the mining of bauxite uses relatively little energy, the chemical process of alumina production in a refinery requires significant amounts of thermal energy. The electrochemical reduction of alumina to aluminium metal in a smelter requires the most energy input of all the processes, in the form of electrical energy. The casting process requires thermal energy inputs, though these are small compared to the refining and smelting processes.

Hydropower has always been and continues to be the most important source of electrical energy for the aluminium smelting process. From an environmental standpoint, different energy sources have different impacts to realize the same amount of energy. For instance, the carbon dioxide emissions impact of producing 1 MWh from coal has a different environmental (CO2 emissions) impact to that of hydroelectric power production.

Between 2000 and 2005 total direct greenhouse gas emissions from the production processes of primary aluminium, including bauxite mining, alumina refining, anode production, aluminium smelting and casting were reduced by 14 percent, despite a 20 percent growth in primary aluminium production covered in the survey.

The high share of hydropower in the electricity mix and the reductions of direct and indirect greenhouse gas emission have resulted in a decrease from 12 to 10 tonnes of CO2 equivalents for every tonne of aluminium produced since 2000.

Over the same period, the production of aluminium from recycled products worldwide rose from 13 to 15 million tonnes per year, saving energy and avoiding greenhouse gas emissions while meeting the demands of modern society for strong, lightweight, safe and sustainable aluminium products. Recycling of aluminium products needs only 5% of the energy required for primary aluminium production and avoids over 95% of the emissions.