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Transmission lines for the Pilbara transmission project, part of Fortescue Metals Group's Pilbara Energy Connect project in Western Australia. |
Fossil fuels dominate both the operating and planned power generation capacity of Western Australia's metals and mining sector, despite a plethora of carbon-neutral targets, according to S&P Global Market Intelligence data.
Globally, miners are at the early stages of reducing their heavy reliance on fossil fuels for both power generation and for transport, including on-site trucks and trains to carry ore to port. They have undertaken various initiatives to decarbonize these parts of their business by increasing renewable power generation and fleet and rail electrification.
As the miner that contributes the most to Western Australia's standing as the world's largest iron ore-producing jurisdiction, Rio Tinto Group has the highest operating capacity with 516 MW. Of this capacity, 481MW is gas-powered, according to the data by which the capacity is apportioned according to ownership share.
Similarly, 258MW of Alcoa Corp.'s 260MW of operating power is gas-fired, as is all of its 120MW of planned capacity.
Taking fossil fuels out of mine sites completely will "take decades," veteran independent analyst Peter Strachan told Market Intelligence.
"Gradually they will be able to reduce their reliance on fossil fuels by putting in more photovoltaics and battery storage, but it's going to take a long time to actually eliminate fossil fuel use completely," said Strachan, who has worked with the industry for 30 years.
"Gas will be a backup at night time, with less of it being burned during the day when their solar power kicks in."
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BHP Group, Western Australia's second-largest iron ore producer, has 293MW of operating and planned capacity. All of gold miner Newcrest Mining Ltd.'s 206MW of operating capacity is fossil fuel-fired, with 193MW from gas and 13MW from oil.
South32 Ltd., whose entire 186MW capacity in the state is coal-fired at its 86%-owned Worsley alumina refinery, also uses a small amount of biomass for power generation.
All of Fortescue Metals Group Ltd.'s 125MW operating capacity is gas-fired. CEO Elizabeth Gaines told Market Intelligence that "decarbonizing the iron ore industry's mining fleets is a critical element to ultimately decarbonizing the steel making value chain."
The top companies are making efforts to improve their share of renewables. Rio Tinto has a renewable energy source, a 34MW solar farm under construction, to power its Gudai-Darri mine.
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Switching to renewable energy
Alcoa will trial technology at the Wagerup alumina refinery using renewable energy to capture waste heat and produce high pressure steam, which would then be used to provide process heat, displacing the use of natural gas for steam generation. This could cut Wagerup's carbon footprint by about 70%, according to a company statement to Market Intelligence.
BHP signed a renewable power purchase agreement that will supply up to half its electricity needs at the Kwinana nickel refinery and 30% of its electricity needs at the Kalgoorlie nickel smelter from the Merredin solar farm.
The company aims to "progressively shift to powering our operated mines from renewable sources" as part of its goal to cut operational greenhouse gas emissions by at least 30% from fiscal 2020 levels by fiscal 2030, according to a BHP spokesperson. BHP also announced plans to build two solar farms and a battery storage system to help power the Mount Keith and Leinster mines at its Nickel West operations.
Newcrest has developed greenhouse gas management plans for each of its managed operating sites to "understand, define and action abatement opportunities," a spokesperson said in an interview.
Worsley is among the "big contributors" to South32's Scope 1 and 2 emissions — direct greenhouse gas emissions from operations in which companies have an equity interest and indirect emissions from the generation of purchased energy at the operations.
A prefeasibility study for the conversion of a coal-fired boiler to natural gas at Worsley is due in fiscal 2022, according to its 2021 Sustainability Development Report.
Fortescue plans to cut its net operational emissions from its fiscal 2020 baseline by at least 3% annually on its way to a 2030 carbon neutral target, CEO Gaines said.
Fortescue and its project partners have announced more than US$800 million in energy infrastructure projects that will increase use of renewable energy, including the Pilbara Energy Connect project to build transmission infrastructure and provide a hybrid solar, gas energy solution for its operations, plus the Chichester solar gas hybrid project.
Once these are completed, about 25% of Fortescue's stationary energy will be powered by solar, Gaines said, and Fortescue plans to integrate "significantly more renewable energy into the network in the future, which will be facilitated through our investment in transmission infrastructure."
Rio Tinto and South32 declined to comment for this story.