Running on renewables: U.S. Borax mine in eastern Kern becomes first open-pit operation in the world to fuel heavy machinery entirely with renewable diesel
Jun. 19—Gigantic trucks used for hauling and loading materials at the U.S. Borax mine in eastern Kern have become the latest tools for reducing greenhouse gas emissions in California.
Instead of fueling up with conventional diesel, owner Rio Tinto says it has converted all heavy equipment at the mine to run on renewable diesel. The move is expected to cut up to 45,000 tons per year of greenhouse gas emissions, the equivalent of taking 9,600 cars off the road.
Rio Tinto Minerals Chief Exec Sinead Kaufman said the effort makes the facility the first open-pit mine on the planet to run entirely on renewable diesel — in this case, a mixture made from cooking oil and rendered animal fats.
"This is an excellent example of what happens when internal and external partners collaborate toward a carbon reduction goal," Kaufman said in a news release. He added that the project would not have happened without the support of state government, and that the success of the project will allow the company to explore further opportunities to decarbonize its global operations.
The conversion to 100% renewable diesel followed testing done last year at the U.S. Borax mine in partnership with Finnish refiner Neste, which provided the fuel, and engine-maker Rolls-Royce.
An assessment of the tests' results found the machines that were switched to renewable diesel performed similarly and were just as reliable as vehicles that ran on conventional diesel. Additional tests were done in the Salt Lake City area.
The chief operating officer of London- and Melbourne-based Rio Tinto's borates division, Ryan Harnden, said a big benefit of switching fuels is that the company can continue to use its existing fleet while it works to achieve net-zero carbon emissions by 2050.
Renewable diesel, estimated to cut 75% of CO2 emissions over the life cycle of the fuel, is seen as a growth industry in Kern. Two existing refineries in the county hope to begin producing the fuel by the end of this year. As it stands, the biggest share of California's renewable diesel comes from Singapore.
Rio Tinto noted in a news release issued after the conversion project was completed in late May that the federal Environmental Protection Agency was part of the project. It noted renewable diesel won't just be used as vehicle fuel but will also be deployed in the mine's blasting processes.
Business editor John Cox can be reached by phone at 661-395-7404.
