Greenhouse gas emissions
We emitted fewer emissions for every tonne of material we moved.
Our approach
Our work involves using large amounts of energy to move large volumes of earth and coal. Our energy use forms a large proportion our greenhouse gas emissions. By moving material in the most efficient way possible, we directly reduce our energy use, greenhouse gas emissions and costs.
We track our energy use for every unit of work we do1 , set voluntary internal targets for the amount of greenhouse gas emissions produced per unit of work and report our performance using the measure amount of greenhouse gas emissions per unit of work. This measure helps drive efficiencies and behavioural change in our business to reduce greenhouse gas emissions from energy used during the mining process.
In addition to the emissions produced from the energy we use, our total greenhouse gas emissions include fugitive emissions. Fugitive emissions of carbon dioxide and methane are naturally occurring in coal seams and are released to the atmosphere during the mining process. Fugitive emissions from open cut mining are not yet able to be accurately measured and we have no control over their release. Fugitive emissions are estimated to be a large proportion of our total greenhouse gas emission footprint.
2009 performance
During 2009 we moved about 460 million tonnes of material compared with 530 million tonnes moved in 2008. While we moved more material as per our mine plans, our business reduced greenhouse gas emissions per tonne of material moved by seven per cent. These improvements largely resulted from productivity and energy efficiency initiatives identified by our ongoing business improvement programme.
The coal seam methane capture pilot project at Mount Thorley Warkworth continued through 2009. This programme is investigating the feasibility of draining fugitive emissions of methane from coal before it is mined and using the methane for a beneficial use such as electricity generation. Four gas production wells were drilled in 2009 in preparation for flaring trials scheduled to commence in mid-2010. These trials will provide valuable information on how the methane flows through the coal bearing strata.
1 Where each unit of work equals each tonne of material we move.