The company has signed a 25-year agreement with green energy firm European Energy Australia, which is building the 1.1 gigawatt Upper Calliope solar farm in Queensland which when complete will be the country's largest, Rio said.
Once developed and approved, the solar farm will have the potential to cut down Rio's operating carbon emissions by 1.8 million tonnes per year.
Rio Tinto is Australia's 10th biggest emitter, according to data from the Clean Energy Regulator. In 2022, it reported direct and indirect emissions at 30.3Mt CO2 equivalent, around two-thirds of which came from its aluminium division.
The company tried for years last decade to sell the aging division, before it considered closure, under former chief Jean-Sébastien Jacques.
The construction of the Upper Calliope plant is targeted to start in 2025 or 2026 and will be built at a site about 50 kilometres south-west of Gladstone.
The solar power deal is also expected to provide ways to repower Rio's three production assets in Gladstone — the Boyne aluminium smelter, the Yarwun alumina refinery and the Queensland Alumina refinery, the company said in a statement.
The mining giant in June 2022 asked for proposals to develop wind and solar energy plants in Australia's Queensland state to power three of its aluminium projects by 2030.
Upper Calliope is the first successful applicant in a formal request for proposals made by Rio for renewable power and firming projects in Central and Southern Queensland, it said.
