Energy is an essential component in alumina and aluminium production. As both processes are energy intensive, it represents approximately 29 per cent of all alumina costs and 36 per cent of all aluminium costs.
Direct energy (coal, natural gas, fuel oil) is largely used in the alumina refining processes and is often determined by regional access to fuel sources. AWAC’s Australian and US refineries are largely dependent on natural gas – a clean transitional fuel - while other refineries rely on a mixture of residual fuel oil, diesel and brown coal. Comparatively small amounts of petrol/gasoline and LPG are used, while biodiesel fuels power some mobile equipment and industrial vehicles on site.
AWAC operates two aluminium smelters located at Point Henry and Portland, Victoria, Australia, which are reliant on indirect energy sources (electricity and steam), most of which are sourced from external providers. Aluminium metal is only formed when a high electric current passes through the pot containing alumina, which is dissolved in molten cryolite.
Energy efficiency is a key factor in sustainable business and environmental performance. AWAC has achieved success in technology and process advancements that have resulted in improved energy consumption and reduced GHG emissions.
Energy security is paramount to AWAC’S operations and in March 2010 Alcoa of Australia signed new base-load electricity contracts with Loy Yang Power to assure power for the Victorian smelters for 20 years to 2036.
The AWAC-owned and operated coal mine and coal fired power station at Anglesea, Victoria continues to provide around 41 per cent of all electricity used at the Point Henry aluminium smelter. (Link here to community)
In 2010 alumina production increased by 12 per cent due to growing demand for aluminium and the gradual recovery from the global economic down turn. This led to subsequent increases in direct energy usage (10 per cent) though indirect energy increased only marginally by 1.6 per cent.
Decreasing energy intensity and subsequent greenhouse gas emissions in refining and smelting processes remains an ongoing challenge. In 2010 indirect energy intensity was 15.05 kilowatt hours (kWh) of electrical energy, a 0.8 per cent drop in energy intensity (for every aluminium kilogram produced from AWAC’s smelters in 2009).
In 2010, Alcoa recommitted to driving further improvements by setting 2020 and 2030 goals focussing on decreasing energy intensity and greenhouse gas emissions
AWAC energy reducing initiatives continuing through 2010 include:
| AWAC Direct energy source | Purchased/produced | 2010 GJ | 2009 GJ | |
| Natural gas | Purchased | 98,747,226 | 95,451,628 | |
| Diesel | Purchased | 1,764,843 | 1,287,256 | |
| Petrol/gasoline | Purchased | 96,932 | 136,732 | |
| Propane | Purchased | 6,173 | 6,084 | |
| Coal | Produced | 17,269,657 | 13,823,366 | |
| Residual fuel oil | Purchased | 46,676,760 | 37,445,922 | |
| Biodiesel | Purchased | 1,753 | ||
| Total | 164,563,345 | 148,150,987 |
| Full Facility 2010 GJ | Full Facility 2009 GJ | |||
| Electricity | (Non-renewable) | 29,365,401 | 30,840,739 | |
| Electricity | (Renewable) | 1,595,610 | 984,820 | |
| Electricity | 30,961,011 | 31,825,559 | ||
| Steam | 12,311,274 | 10,768,000 |