Rio Tinto Kennecott is converting all heavy machinery to renewable diesel

BINGHAM CANYON – Over the past decade, Rio Tinto Kennecott – home to the world’s deepest open pit mine – has made great strides in reducing its carbon footprint.

Kennecott in 2019 shut down its last coal-fired power plant, eliminating 6,000 tons of pollutants from the Salt Lake Valley air divide.

To continue this momentum, the mining giant on Tuesday announced a full transition from conventional to renewable diesel for the mine’s entire fleet of 97 haulers and heavy machinery equipment at the mine, concentrator, smelter, refinery and tailings.

After a seven-month trial period, the full transition is expected to reduce the mine’s emissions by 450,000 tonnes – the same reduction as eliminating the annual emissions of over 100,000 cars.

The shift also reduces PM2.5 emissions (particles smaller than 2.5 microns) from the tailpipes of the company’s truck fleet by 40%, a reduction equivalent to eliminating approximately 2.3 billion miles of light vehicle travel annually.

With the retirement of the coal-fired power plant and the recent transition to renewable diesel – along with the installation of a 5 megawatt solar farm and the deployment of electric vehicles for underground copper mining – Kennecott has reduced its overall carbon footprint by more than 80% compared to 2018 levels .

“It’s a huge change,” said Clayton Walker, Chief Operating Officer of Rio Tinto Copper. “I think this is just another step in showing our commitment to making the environment the best we can and trying to show how to do it in a responsible way.”

During the trial run of the renewable diesel program, the company compared the tractors’ acceleration, cycle time, fuel consumption and engine inspection reports, and found renewable diesel to be a good substitute for conventional diesel.

The haulers aren’t small either, often weighing over a million pounds and holding 1,400 gallon fuel tanks.

“It’s like moving a house,” said Aaron Clement, handyman and truck driver at Kennecott. “You don’t have a lot of visibility. It’s definitely an experience.”

Clement said the switch to renewable diesel has not come with any performance disadvantages as far as the operation of the haulers is concerned.

“It’s pretty much identical. Maybe a little less smoking,” Clement said.

Utah Gov. Spencer Cox was on hand for the announcement and said his trips to Kennecott usually coincide with big announcements like the one made Tuesday.

“This is a great model. Companies are doing things like this all over the valley and all over the state,” Cox said. “We’re never going to be able to regulate our way out of some of the (environmental) problems we have, but we can certainly innovate, and that’s the kind of innovation that makes sense. It saves money and it improves the environment .”

He said Utahns can expect more announcements ahead of the upcoming legislative session on how to produce more energy while also “treating the environment in a way that’s good for everyone who lives here.”

Renewable diesel is harnessed from soybeans, animal fat and cooking oil, making it much cleaner than traditional fuel sources. It’s also sourced from the US, something Walker said was important to the company.

“Locally, there was no source of renewable diesel here, so our thing was, ‘How do we get it?'” Walker said.

Steven Ledbetter, executive vice president of HF Sinclair — the company that supplies Kennecott with renewable diesel — said it is transported via a pipeline, further reducing the emissions that would come with transporting it by trucks hauling the fuel.

With more emissions reductions on the horizon, Rio Tinto Kennecott aims to be net zero by 2050.