Rio Tinto confirmed in early June that its U.S. Borax operation in Boron, California became the world’s first open-pit mine to complete a full transition of its heavy machinery from fossil fuel to renewable diesel.
To put the scope of the milestone in perspective, the global miner said the change brings an anticipated CO2 equivalent reduction of up to 45,000 tonnes per year.
The move follows an initial trial last year during which it switched fossil diesel to renewable diesel in a U.S. Borax haul truck, in partnership with Neste and Rolls-Royce; U.S. Borax used Neste MY Renewable Diesel during the 2022 trial.
“Made from sustainably sourced, 100% renewable raw materials such as used cooking oil and animal fat waste, the use of Neste MY Renewable Diesel can reduce greenhouse gas emissions by up to 75% over the life cycle of the fuel compared to fossil diesel,” the company said of the Neste technology.
Trail results revealed a truck running on renewable diesel delivered similar performance and reliability as trucks running on conventional diesel. Based on the positive results, Rio Tinto continued to work with Rolls-Royce, Neste, the Environmental Protection Agency, and the state of California to fully transition the heavy machinery fleet onsite to renewable diesel at the end of May.
The transition included all heavy machinery on the property from haul trucks to loaders, and the renewable diesel is even used in blasting.
Rio Tinto Minerals Chief Executive Sinead Kaufman said: “We are proud that our U.S. Borax operations have become the first open-pit mine to operate a fleet running entirely on renewable diesel. This is an excellent example of what happens when internal and external partners collaborate toward a carbon reduction goal. Support from the state of California has also been incredibly important, as without their vision, this would not have been possible.
“The transition at Boron is an important first step and will undoubtedly lead to further opportunities to decarbonize our global operations. Renewable diesel is one of several sustainability solutions that Rio Tinto is using to transform its businesses.”
The conversion supports Rio Tinto’s global decarbonization objectives, which include a 50% reduction in Scope 1 and 2 emissions by 2030 and a commitment to reach net zero by 2050. The company estimates carbon emissions from the use of diesel in its mobile fleet and rail accounted for 13% of its Scope 1 and 2 emissions in 2022.