Rio Tinto, the world’s second largest mining company, has announced it will invest $1 billion on reducing its carbon footprint in the next five years, that it will cut is emissions by 15% by 2030, and that intends to reach zero net emissions by 2050. This comes a week after announcing its first significant solar farm, a 34 MW installation in the Pilbara region of Western Australia which will power the company’s Koodaideri iron mine.
The Pilbara region contains huge iron ore deposits, with Rio Tinto alone controlling 16 iron ore mines with 10,500 employees; the region also has some manganese, petroleum, natural gas, and other metals. At peak output times the Koodaideri solar farm will provide all the mine’s energy needs and will fulfil 65% of its demand overall with the help of a 12 MWh lithium-ion battery system situated in the iron ore mining town of Tom Price.
The Koodaideri mine itself was approved in 2019 and is under construction, with a price tag of $2.6 billion and an expected annual output of 43 million tons. Construction of the accompanying solar plant, which costs $98 million, should begin this year to be ready with the mine in 2021. Rio Tinto has previously considered a 6.7 MW solar installation at its Weipa bauxite operation in Queensland, eventually settling on 1.7 MW which was commissioned in 2016. Numerous small-scale solar plants are also already in operation across Rio Tinto’s railways. The company has initiated studies to examine further possibilities of emissions reduction from its sites in the Pilbara, in co-operation with the Western Australia state government, most likely using solar and energy storage, but with wind power also under consideration.
Western Australia is the worst performing Australian state for renewable energy and is the only state with no renewable energy target, despite having exceptional solar radiation. Rio Tinto is by no means the first company to install renewable power with a mining project in Western Australia. One such project of greater scale is Fortescue Metals and Alinta Energy’s Chichester Solar Gas Hybrid. Their development of the 60 MW solar, 35 MW/11 MWh battery, 145 MW natural gas project was announced last October and will be completed earlier in 2021. In recent years many lesser projects across Western Australia have been announced, mixing solar, gas, energy storage, and occasionally diesel and wind. Last month, Fortescue Metals announced the largest such yet, the Pilbara Energy Generation Project – a 150 MW gas, 150 MW solar project. Along with the Chichester Solar Gas Hybrid, it will that advantage of the $250 million Pilbara Transmission Project, making Fortescue’s Chichester hub substantially solar-powered. Further projects can be expected to follow this expansion of the transmission infrastructure.
These developments reflect a global trend towards renewable-powered mining that’s by far the most pronounced with solar in Western Australia and the Atacama Desert in Chile, but is also seen on a small scale in numerous African countries, where the national grid is unreliable. In Canada, it’s wind which has been installed at mining operations, such as the 9.2 MW Diavik plant.