Alumina refining is emissions intensive and requires continuous, high-temperature process heat. At Yarwun, steam for the digestion process is currently supplied by three coal boilers and a gas-fired cogeneration plant. Replacing this low-cost, reliable fossil-fuel heat with renewable electricity, requires proven technology capable of delivering large-scale baseload steam, as well as substantial upgrades to electrical and site infrastructure. The project addresses the technical, integration, cost and operational barriers to using electric thermal energy storage in a brownfield industrial facility.
Rio Tinto will complete a feasibility study, then subject to a stage gate review by ARENA and final investment decision by Rio Tinto, construct, commission and operate a large-scale Rondo Heat Battery at the Yarwun alumina refinery. The system will use resistive electric heating to store energy in refractory bricks at temperatures of around 1,100°C. Stored heat will be discharged as hot air through a heat recovery steam generator to produce continuous process steam.
