I recently returned from an extended stay in Europe, where most new cars run on diesel. Those cars are typically a lot more fuel-efficient than our gas guzzlers, which makes me wonder why there aren't more diesels on American roads.
I recently returned from an extended stay in Europe, where most new cars run on diesel. Those cars are typically a lot more fuel-efficient than our gas guzzlers, which makes me wonder why there aren't more diesels on American roads. I know that diesel has a reputation for causing dirtier tailpipe emissions than petrol, but isn't that a bygone problem?
Technological wizardry has, indeed, made diesel-powered vehicles vastly cleaner than in olden days. As a result, lots of gearheads are touting diesels as finally safe enough for American motorists, who will dig the cars' impressive fuel-economy numbers. There's considerable excitement on these shores, for example, over the impending arrival of the 2009 Volkswagen Jetta TDi, a "clean diesel" vehicle that purportedly gets 50 miles per gallon on the highway yet spews out far less soot than the diesels of yore, which wreaked havoc on air quality. So will the erstwhile environmental boogeyman of diesel fuel end up saving us all? The Lantern is still far from convinced.
Diesel, named after German engineer Rudolf Diesel, has traditionally been simpler to refine than gasoline, although making it also requires more crude oil per gallon. The end result is a fuel that boasts much greater energy density than gasoline, which explains why diesel cars get up to 40 percent more miles per gallon than their petrol counterparts. The higher energy density also means that burning a gallon of diesel emits more greenhouse gases than burning a gallon of gasoline—about 15 percent more, to be specific. But due to the appreciable fuel-economy savings, diesel cars usually emit less of these gases per mile driven.
There's a more disturbing difference between diesel and gasoline: Burning diesel also emits nasty particulates and smog-forming nitrogen oxides, as should be apparent to anyone who's ever gotten a mo