Rio Tinto and Edify Energy have signed two new solar and battery hybrid services agreements (HSAs) to increase the supply of reliable, competitively priced electricity to Rio Tinto’s Gladstone aluminum operations in Queensland. Under the agreements, Rio Tinto will purchase 90% of the power and battery storage capacity generated by the Smoky Creek & Guthrie’s Gap Solar Power Stations for 20 years.

Edify Energy will build, own, and operate the projects, with construction due to begin in late 2025 and targeting completion in 2028.

Located in Central Queensland, the adjacent Smoky Creek & Guthrie’s Gap Solar Power Stations will together feature 600MW_ac of solar and 600MW / 2,400MWh of battery storage. When combined with the 2.2GW of renewable wind and solar PPAs Rio Tinto announced for its Gladstone operations in 2024, the Smoky Creek & Guthrie’s Gap agreements help secure a total of 2.7GW of future wind and solar energy in Queensland.

Together, the four contracted projects are expected to supply 80% of Boyne smelter’s annual average electricity demand, reducing the smelter’s scope 1 and 2 emissions by 70%, or 5.6Mt of carbon dioxide equivalent per year. This is the equivalent of removing about 2 million internal combustion engine cars from the road.

Rio Tinto's 90% share of the Smoky Creek & Guthrie’s Gap battery system capacity amounts to 2,160MWh, which will provide about 30% of the firming required to repower the Boyne smelter with renewable energy. It will store green energy for reliable use during peak demand periods or low solar output, which will improve stability and resilience of Queensland’s power network.

Boyne Smelters Limited (BSL) has been operating since 1982 and is Australia’s second largest aluminium smelter. The operation is located at Boyne Island in Central Queensland and activities include manufacturing carbon anodes in the carbon plant, aluminum production (smelting) in reduction lines, and casting of molten metal into aluminum products ready to ship. The smelter is adjacent to, and connected via a conveyor belt, to the Queensland Alumina Limited Refinery for the supply of alumina.

BSL has expanded significantly since the smelter opened in 1982. A series of multimillion dollar investments increased its capacity from 210,000 tonnes of aluminum per year to today’s capacity of more than 500,000 tonnes of aluminum a year.

BSL continues to invest in a range of technologies including automation projects and also looks for ways to be more energy efficient. For example, in 2018, BSL implemented a A$23-million Undercell Bus Bar project to increase production by an estimated 9,200 tonnes of metal a year without using additional electricity.

BSL is a joint venture between Rio Tinto (73.5%); YKK Aluminium (9.50%); UACJ Australia (9.29%); and Southern Cross Aluminium (7.71%).

Rio Tinto’s integrated aluminum production chain in Queensland is a significant economic driver for the state and Australia, directly employing more than 4500 people and supporting thousands more livelihoods. The company’s operations in Gladstone alone account for more than 3000 jobs, with 1000 of those at the Boyne smelter.

Rio Tinto’s three production assets in the Gladstone region are the Boyne aluminum smelter, the Yarwun alumina refinery and the Queensland alumina refinery.