Rio Tinto will replace its entire fossil diesel consumption with renewable diesel at its Kennecott copper operation in Utah from 2024, the mining company has confirmed.

Kennecott’s fleet of 90 haul trucks and all heavy machinery will begin to transition to renewable diesel in the March quarter of 2024, along with consumption from the concentrator, smelter and refinery. HF Sinclair is set to provide the fuel.

The transition will reduce Kennecott’s Scope 1 carbon emissions by approximately 495,000 t/y of CO2 equivalent, comparable to eliminating the annual emissions of more than 107,000 passenger cars.

The renewable diesel is made from renewable biogenic materials sourced in the US. It will be supplied through the existing diesel supply chain, as part of a continuing partnership between Kennecott and HF Sinclair.

Rio Tinto Copper Chief Operating Officer, Clayton Walker, said: “Transitioning Kennecott completely to renewable diesel builds on a suite of decarbonisation initiatives that have reduced carbon emissions from the operation by 65% since 2019. This is an important next step in our commitment to finding new and better ways to reduce operational emissions, while producing materials essential to the global energy transition.”

HF Sinclair Executive Vice President, Commercial, Steven Ledbetter, said: “As a long-time supplier of Rio Tinto and a fellow operator in the Rocky Mountain region, we are pleased to support Rio Tinto’s sustainability journey with a low-carbon fuel made at our facilities. This is a great step demonstrating our continued progress to meet the evolving energy needs of our customers.”

Rio Tinto is targeting reductions in Scope 1 and 2 carbon emissions of 50% by 2030 and net zero by 2050.

Rio Tinto Chief Decarbonisation Officer, Jonathon McCarthy, said: “Combined with Rio Tinto’s U.S. Borax operation – which completed the full transition of its heavy machinery from fossil diesel to renewable diesel in May 2023 – this initiative would replace 11% of Rio Tinto’s global fossil diesel consumption with renewable diesel.

“The use of drop-in fuel such as renewable diesel will allow Rio Tinto to reduce emissions in the short term, complementing ongoing work towards the commercial readiness of longer-term technical solutions such as battery electric haul trucks.”

The decision to convert to renewable diesel comes after a successful seven-month trial at Kennecott’s Bingham Canyon mine. This trial was conducted in collaboration with Cummins to test renewable diesel in different operational environments and on different equipment which supported the decision of OEM to approve the use of renewable diesel in Rio’s equipment.