These are heady days for diesel.
Last week new federal regulations went into effect mandating that vehicles use "clean" diesel fuel — a new type of diesel with a 97 percent reduction in sulfur content. And though the old diesel can be used until 2010, the new stuff is now available around the country.
This means cleaner air, cleaner engines and advanced emission-control devices are on the way. It also means automakers are planning to bring more diesels to the U.S., finally addressing the biggest problem we have had with diesels: limited availability.
Consumers are desperate to find alternatives to gasoline, but most diesels sold here are heavy-duty pickups and commercial vans. If buyers want fuel-efficient diesels they have only three passenger cars from which to choose: diesel versions of Volkswagen's Jetta and New Beetle, and — starting around right now — the new Mercedes-Benz E320 BlueTec luxury sedan. DaimlerChrysler's Jeep subsidiary will begin selling a diesel version of its Grand Cherokee SUV early next year.
On Oct. 9, Mercedes-Benz announced it would start selling the E320 in the U.S. and Canada. The BlueTec engine, which requires the new, cleaner fuel, is a breakthrough for diesel fans — or people who just like cool technology. The company says BlueTec makes for the world's cleanest diesel cars, thanks to a sophisticated engine design and a special exhaust treatment system. And while other diesels scramble to keep up with increasingly stringent emission requirements, BlueTec meets today's standards and anticipates stricter regulations in the future.
The $52,000 E320 BlueTec, a version of Mercedes' midsize E-Class line, is also the only diesel luxury car available in the U.S. (Europeans can buy diesel versions of such high-end cars as BMW's flagship 7 Series sedan and Land Rover's Range Rover). But Benz also plans to begin selling BlueTec versions of its M-, R- and GL-Class SUVs in 2008.
The lack of choices is a shame, because diesels deliver great gas mileage. The diesel Jetta and New Beetle both rank among the U.S. market's ten most fuel-efficient cars.
But automakers have feared to offer diesel in high volume here because some buyers are still afraid of the cars. By the 1970s and '80s, diesels had developed a reputation for being noisy, stinky and noxious. Sometimes they would emit clouds of black smoke. Modern diesels are nothing like this, but these bad memories don't just go away over time.
Tough emission standards also make selling diesels difficult. Due to regulations that vary in strictness on a state-by-state basis, you cannot buy many diesels in Maine, Vermont, Massachusetts, New York or California. (If you are interested in buying a diesel, you should call your local dealership to check if it is actually available.)
Availability of diesel fuel has also been a problem. According to the Maryland-based Diesel Technology Forum, an organization created by companies working on the technology (including the Big Three, all of whom sell diesels), only 42 percent of American filling stations sell the fuel.
Another factor in diesel's low profile is the fact that diesels may be cleaner and more efficient than ever, but reducing hazardous diesel emissions has been a slow process — and not everybody believes in diesel engines. Porsche chairman Wendelin Wiedeking has been among the most outspoken critics of diesel engines; he told us in an interview that he believes they are bad for the environment.
"Due to the deployment of three-way catalytic converter drive units, gasoline engines have unparalleled environmental compatibility," Wiedeking said in a 2004 statement. "Moreover, we are of the opinion that — in terms of consumption — the gasoline engine has more development potential than the diesel engine."
On the other hand, the Diesel Technology Forum says clean-diesel engines emit lower levels of certain emissions compared with gasoline engines ("clean diesel," in this case, meaning a process combining advancements in diesel engines, cleaner-burning fuels and emission-control systems).
"Diesel emits only small amounts of carbon monoxide, hydrocarbons and carbon dioxide," the DTF has said. "In addition, the fuel efficiency of diesel engines means they burn considerably less fossil fuel."
Whether you are pro- or anti-diesel, the reality of the situation is that diesel is on the rise in America. Hence, our survey of some of the vehicles currently on the market. Mileage information came from the U.S. Environmental Protection Agency and Diesel Technology Forum. The roster is limited at the moment, perhaps. But the explosion of recent diesel news tells us the list is bound to look sexier and more complete very, very soon.