A roadmap to net zero emissions has identified four key technologies ripe for decarbonisation - mechanical vapour recompression (MVR), electric boilers, electric calcination, and hydrogen calcination.
In combination, these four technologies have the potential to reduce emissions from Australia’s six alumina refineries by up to 98 per cent.
Entitled A Roadmap for Decarbonising Australian Alumina Refining, the report has been released by the Australian Renewable Energy Agency (ARENA), and prepared by Deloitte in consultation with Australia’s three major alumina producers: Alcoa, Rio Tinto and South32.
The Roadmap provides a framework for future policy and investment decisions, and serves as a call to action for public and private sectors to collaboratively transition this ‘hard-to-abate’ sector into an industry at the forefront of the transition to net zero.
Australia is the largest exporter of alumina globally, which is expected to contribute $7.5 billion of exports to the Australian economy in 2022. The country also has an abundance of low-cost renewable energy resources and significant local expertise, both of which are necessary for this sector to achieve its net zero ambitions.
Alumina is the precursor to aluminium and alumina refining is an energy and emissions intensive step in the aluminium value chain.
The industry contributes three per cent of Australia’s total emissions and consumes more than 221 petajoules of energy each year, more than the total energy consumption of Tasmania or the Northern Territory. Approximately 95 per cent of emissions are from the onsite consumption of fossil fuels for process heating.
Compared to bauxite production and aluminium smelting, the abatement pathway for alumina refining in Australia is less clear. Alumina refining is a ‘hard-to-abate’ industry because there is a lack of low emissions alternatives that are technically mature and commercially feasible. Targeted intervention and transformational change will be needed to reduce emissions from this sector.
The four technologies identified in the report are at varying stages of technological and commercial maturity and require significant investment to support decarbonisation.
The report points out that there is no one-size-fits-all approach and different refineries will require different combinations of technologies to achieve net zero due to the specific barriers and opportunities of individual refineries.
The Roadmap highlights early deployment of electric boilers and MVR could result in emissions reductions from 2027, while hydrogen and electric calcination technologies are anticipated to be deployed from the mid 2030s.
“These technologies require broader ecosystem development to enable uptake including 3-5GW of new firmed renewable generation, new transmission infrastructure, large scale renewable hydrogen supply chains, and market and regulatory frameworks that support decarbonisation. Coordinated investment will be required from governments and industry to support this transition,” the report said.
ARENA CEO Darren Miller said the Roadmap provides a clear vision for decarbonising one of Australia’s most emissions intensive industries.
“Alumina refining has always been considered a hard-to-abate sector with significant barriers to reducing emissions. Now, we have Australia’s biggest alumina producers coming together with ARENA to develop a clear and credible pathway to reducing emissions in the industry,” Miller concluded.