(Alex Goldmark, Transportation Nation) New diesel fuel economy standards are expected to be finalized within a week and some in the diesel industry are taking the occasion to remind us about the other way to reduce pollution, making engine technology cleaner with clean diesel. The new regulations are expected to require diesel engines to increase miles per gallon performance primarily for light trucks and heavy-duty vehicles, but regulating that category is no easy task.
In Europe, 50% of the cars on the road are diesel according to the Diesel Technology Forum. Here in the U.S though, diesel vehicles make up just 3% of of our vehicles, accounting for 10% of our nation's oil consumption, and 20% of the transit-related pollution. That's an environmental opportunity when you think of what a few extra miles-per-gallon would do with a bus or truck that travels over a million miles during its lifetime.
Its a complicated matter though to set fuel efficiency standards for heavy duty vehicles, a category that covers tractor trailers as well as construction vehicles like dump trucks. The fuel is consumed in many different ways, it could be used making cross country highway trips or in operating equipment on the truck while stationary like a cement mixer. Some vehicles go 100,000 miles a year, others may not travel more than a few hundred, like a fire truck. Some argue per-mile efficiency may not be the best metric for reducing diesel consumption and pollution across the board. The NYT has a nice explanation of this and other regulatory puzzles that explain some of the delay in targeting this class of transit polluter.
Mileage standards are certainly one way to reduce diesel pollution, but technology is another. In anticipation of the new regulations, clean diesel advocates at the Diesel Technology Forum pointed out a 52% rise in clean diesel vehicle sales over a year ago. No one expects clean diesel to rival hybrids for the mantle of greener cars, but it may well be a growth market and an eco-opportunity.
One recent study by the National Academy of Sciences estimates that we can cut fuel consumption in heavy-duty vehicles almost in half with the combination of new technologies and diesel fuel economy standards. That's likely the kind of hopeful case for change the Obama administration will make when they release the official standards.