Rio Tinto Kennecott is converting its fleet to “renewable diesel” to improve air quality

BINGHAM CANYON MINE, Utah – Aaron Clement drives one of the giant trucks at the largest open-pit copper mine in the world.

“It’s like moving a house,” he jokes.

Clement, who works in the truck shop at Rio Tinto Kennecott's Bingham Canyon Mine, took part in a pilot project using a new type of fuel for the massive mining equipment. They switched from a traditional fossil fuel to a “renewable diesel” made from soybeans and food waste. The company has even installed a special pipeline in the mine for this purpose.

“As far as performance goes? It’s pretty much identical,” Clement told FOX 13 News about the difference between the fuels. “I don’t notice much. Maybe smoke a little less. Other than that, nothing really changes.”

On Tuesday, Rio Tinto Kennecott announced it has converted its entire fleet of mining vehicles to renewable diesel, which it says will result in fewer emissions in Utah's airshed.

“If you include passenger vehicles, that’s over 100,000 cars that we’ve taken off the road,” said Nate Foster, chief executive of Rio Tinto Kennecott. “About 40%.”

A massive operation like the Bingham Canyon Mine, which supplies about 12% of America's copper (an increasingly sought-after mineral in our electrified world), could have a positive impact on the Wasatch Front's air quality. The company previously closed a coal-fired power plant in favor of a solar farm that it wants to expand.

“As we head into the time of year where we have air quality issues as the inversion sets in, this will definitely be helpful,” Gov. Spencer Cox told reporters at Tuesday's announcement.

Northern Utah continually struggles with air quality. The topography of the Wasatch Front contributes to an inversion that traps pollution in the Ogden, Salt Lake, and Utah valleys. But state leaders insist air quality has improved in recent years as Utahns switch to cleaner-burning fossil fuels or switch to electric vehicles.

“Although we are growing as a state, not only our per capita emissions but also our overall net emissions have declined significantly,” said Governor Cox. “We still have a long way to go and we continue to work on it, but we are proud of what we have achieved.”

Rio Tinto Kennecott's voluntary decision to switch to renewable energy has been praised by environmentalists.

“It is not my job to congratulate Rio Tinto Kenecott very often. This will mean an improvement in local air quality,” said Dr. Brian Moench, executive director of Utah Physicians for a Healthy Environment.

However, Dr. Moench said he had concerns about sourcing the ingredients for renewable diesel and whether taking agricultural land and converting it to fuel production would have a negative impact on the global climate.

Rio Tinto Kennecott said it is also experimenting with electric vehicles. Given the massive size of the equipment used at the Bingham Canyon Mine, significant battery sizes and strengths would be required to operate.

“It really depends on where the technology is in the industry today,” Foster said. “We do this in our underground mine with smaller equipment.”