Miner Rio Tinto is set to lead the development of Australia’s biggest solar power project, near Gladstone. The company has committed to buying all electricity generated from the 1.1 GW Upper Calliope solar farm to power its Queensland aluminium operations.  

This move aligns with Rio Tinto’s climate goal of reducing Scope 1 and Scope 2 carbon emissions by half this decade.

The power purchase agreement with European Energy Australia spans 25 years, with the solar farm's construction and operation handled by European Energy pending development and grid connection approvals.

Once approved and developed, Upper Calliope would have the potential to lower Rio Tinto's operating carbon emissions by 1.8-million tonnes a year.

The initiative not only strengthens renewable energy in one of Australia's vital industrial hubs but also lays the foundation for potentially repowering Rio Tinto's key Gladstone production assets, including the Boyne aluminum smelter, Yarwun alumina refinery and the Queensland Alumina refinery.

“Competitive capacity, firming and transmission are critical to developing a modern energy system that can ensure more large-scale renewables development in Queensland and help guarantee the future of Australian industry,” said Rio Tinto CEO Jakob Stausholm.

Construction of the Upper Calliope plant is set to start in 2025 or 2026 and, when complete, it will provide enough electricity to meet about 5% of Queensland’s current demand.

Covering an expansive 2 400 ha, the plant's construction is anticipated to span two years, engaging a workforce of 1 000 during this period and supporting 100 direct and indirect jobs when operational.

Upper Calliope stands as the inaugural success in Rio Tinto’s formal request for proposals, focusing on renewable power and firming projects in central and southern Queensland. While the company evaluates additional proposals, solutions and partnerships to effectively address the energy needs of its three production assets in the Gladstone region, it emphasises the requirement for more than 1 GW of reliable power, equivalent to more than 4 GW of quality wind or solar power with firming. Potential further electrification of plant processes could increase their electricity demand in the future.