Automakers are working in many ways to meet new tough fuel economy standards — both national goals set by the Obama administration and state standards, like California’s new rules passed Friday requiring that 15 percent of new vehicles sold in the state must produce little or no air pollution by 2025.
But carmakers aren’t just turning to new technologies like hybrid and electric cars. Many in the auto industry are taking a second look at an old technology: the diesel engine.
University of Michigan professor Margaret Wooldridge explains how an engine running on diesel fuel differs from a gasoline-powered engine.
“The strategy for introducing the fuel into the [diesel] engine is you inject it directly into the engine,” she says. “For a gasoline engine it needs a spark plug to ignite the fuel; a diesel engine doesn’t have a spark plug.”