As the car market shifts toward electrification, many in the auto industry say diesel's days are numbered.
But new technology and a resurgence in some key segments show it might not be over yet.
Diesel has long been the powertrain of choice for commercial vehicles and heavy machinery of all kinds. But it was once also hailed in many countries as an excellent choice for achieving greater fuel efficiency and lower carbon emissions in ordinary passenger cars.
However, diesel's reputation suffered serious blows from concerns over the pollutants diesel engines emit and from the Volkswagen diesel test cheating scandal that rocked the automotive world. Now, many governments and automakers are promoting electric and hybrid vehicles for efficiency, performance and emissions reduction.
Yet diesel advocates see opportunity. The industry has stepped up the development of technologies that reduce harmful pollutants. Diesel vehicles now can run either partially or entirely on renewable fuel from organic waste. And diesel powertrains can be used along with electric motors to make diesel hybrids.
Diesel never took off in passenger cars in the United States the way it did in the Europe, but it has found a place in some characteristically American segments — pickup trucks and large sport utility vehicles.
In 2019, all three Detroit automakers offered diesel options for consumers, offering half-ton full-size pickups for the first time in years. There are diesel versions of midsize pickups and SUVs, such as the Chevrolet Tahoe and Suburban and the Jeep Wrangler.
Industry executives say the future is electric, but that may take time. Companies bet consumers will want other solutions along the way, even ones, such as diesel, which have been around for more than a century.