Sources of greenhouse gas emissions

Our results

Emissions associated with the generation of electricity and steam purchased (less exports) by our operations contributed almost half (45 per cent) of total greenhouse gas emissions in 2007. The remaining 55 per cent of emissions were associated with on-site emissions as for 2006, and included emissions from the use of fossil fuels, process gases and land management.

• Emissions from the use of fossil fuels, including anodes and reductants.
• Process gases, particularly coal seam gas, carbonates and perfluorocarbons (PFC). Other process gases come from the use of explosives, coal oxidation and from on site landfills.
• Land management, which includes emissions associated with livestock and land clearance (releasing greenhouse gases) minus the uptake from sequestering greenhouse gases by re-vegetating land during and after mining.

We believe it is important to track emissions along the value chain, to understand where emissions are occurring and to reduce these wherever possible.  There are indirect emissions associated with our products over we do not have direct management control. These include emissions from the transport of products, the combustion of coal and from the conversion of iron ore into steel by third parties.

• Third party transport of products and raw materials in 2007 contributed 6.6 million tonnes of CO2-e.
• Based on 2007 coal production, combustion of our coal by customers for electricity generation and steel production generated an estimated 344 million tonnes of CO2-e, a decrease from 2006 which was 364 million tonnes.
• Using our 2007 iron ore production figures, steel manufactured by iron ore customers generated approximately 268 million tonnes of CO2-e. This was an increase from 2006 where customers generated approximately 255 million tonnes of CO2-e. The coal used in this process may be from our coal products and, therefore, these emissions cannot be added to those associated with the combustion of coal by customers, as this would result in double counting.
• Rio Tinto produces more bauxite than is required for the quantity of aluminium we produced.  This additional bauxite is processed by others to produce aluminium.  Based on 2007 bauxite production, the processing of our bauxite produced by external customers generated an estimated 42 million tonnes of CO2-e.