Energy and emissions
We continue to find new ways to use energy more efficiently in our operations. As our assets have grown in size, complexity and diversity, we recognise that energy efficiency could be measured better and ultimately improved.
Energy consumption remains one of our largest operational inputs. An energy minimisation project commissioned in FY19 involved feasibility studies on electric trucks and solar energy on our sites – with our intention for more detailed analyses on these options in FY20.
In addition, we are supporting a Government-led project assessing feasibility of a hydro scheme using mine water from the Stockton mine.
Our total energy consumption is reported in terms of energy consumed (fuel and electricity) by staff and contractors. A total energy use of 1,021,490 gigajoules (“GJ”) was used at our five operational sites and corporate offices in FY19. This is approximately 33 percent higher than FY18.
A significant part of this increase reflects that our three largest sites only reported ten months of energy consumption in FY18 from the date of acquisition.
Overall, total waste rock stripping which drives energy consumption (diesel) increased by 29 percent with an extra 4.5 million bcm waste rock stripped in FY19 compared with FY18. This increase comes from our Stockton, Rotowaro, and Maramarua sites where we have completed extensive mine planning since acquisition to ensure we mine as sustainably as possible. When Bathurst acquired these mines, they had been operating under administration for many years, so whilst coal had been mined, waste stripping had fallen to very low levels.
94 percent of the energy consumed within our sites included fuel used for onsite transport, operations and power. The remaining six percent of energy consumed was purchased electricity.
When comparing energy consumption by operation, there are significant differences which can be accounted for by the scale of the operation and the mine life cycle stage. Stockton mine is the largest consumer of energy and Rotowaro is the second largest energy consumer.
Comparison of energy consumption by operation FY19
*Corporate consumption was at 216GJ of fuel and 308GJ of electricity.
The above graph excludes Escarpment, Cascade and Sullivan mines where consumption was zero.
Greenhouse gas emissions
We participate in the Emissions Trading Scheme (ETS) where pricing of ETS is passed on to our customers as part of the product supply – and we assist our customers to source the best quality energy and the most efficient logistic pathways.
Our mining projects use significant quantities of diesel fuel to extract and transport coal. Electricity consumption is required for coal processing, water treatment plants and mine management systems.
In addition, our coal produced releases GHGs (fugitive emissions) and these are accounted for in the FY19 production tonnages in Scope 1 emissions (direct emissions from Bathurst-owned or controlled sources). We report our GHG emissions with reference to their source as follows:
GHG emissions intensity FY19
Scope 1 & 2 intensity (/t of product coal)
Our reporting of Scope 1 and Scope 2 emissions (indirect emissions from the generation of purchased energy) is consistent with GRI reporting (the Global Reporting Initiative). Accordingly, we have included carbon dioxide in our GHG emissions calculations reported as carbon dioxide equivalents. We have also accounted for minor losses in SF6 gas from electricity transformers.
The total GHG emissions for Scope 1 and 2 for FY19 are 120,527 tonnes CO2e as follows:
- 43 percent related to fugitive emissions of production coal.
- 1 percent related to electricity.
- 56 percent related to fuel consumption.
The reported FY19 GHG emissions are approximately 23 percent greater than in FY18.
Why the change?
Because in FY18 we only reported ten months (from date of acquisition) of GHG emissions for the Stockton, Rotowaro and Maramarua mines. And also, our total waste rock stripping volumes were 29 percent greater at the five operating sites in FY19 compared with FY18.
GHG emissions intensity FY19
|Site||Scope 1 emissions (t/CO2e)||Scope 2 emissions (t/CO2e)||Total
(Scope 1 & 2)