Gas-electric hybrid systems add cost penalties to new cars similar to diesel engines’, yet these types of vehicles are gaining in popularity. “In 2007, 56 percent of consumers said they would consider a hybrid,” says Mike Omotoso, senior manager of powertrain forecasting for JD Power and Associates. “In 2008, that number went up to 62 percent,” he says. The specific cost penalty of both hybrids and diesels depends on which car manufacturer you ask. Jim Lentz, the head of Toyota’s U.S. operations told us that a hybrid system like the one in the Prius is less expensive for them to develop than a 50-state diesel. But Wolfgang Hatz, Audi’s powertrain chief, says that a hybrid system is double the cost of a modern diesel. So who’s right? The answer is contingent upon where a company’s competency lies. European manufacturers traditionally know how to manufacturer and develop diesels at a lower cost because they’ve been serving their home markets for years. The Japanese, on the other hand, have concentrated on hybrids.
Unlike hybrids, which have a green reputation in this country, modern diesels must still overcome the reputation here of those soot-belching, unreliable oil-burners of the past. Additionally, since diesel doesn’t evaporate like gasoline, the pumps are dirtier—no matter how clean those diesel engines are. And then there’s another challenge for diesels—stricter U.S. emission regulations. The 50-state light-duty vehicle limit for emissions of nitrogen oxides is 0.07 grams per mile. In Western Europe, the limit is 0.29. Reducing NOx to nitrogen and oxygen is much harder with a diesel engine because the exhaust is typically cooler and contains less oxygen compared to a gas engine. To meet U.S. regulations, diesel engines are required to use complicated—and expensive—high-pressure fuel injection and after-treatment systems that in some cases inject an aqueous urea solution to handle the NOx. The added expense of course means an even longer payback period for the consumer.
So where does that leave the U.S companies? Ford and GM—and now Chrysler—have access to perfectly competent diesel cars produced by their European arms. When asked about the possibility of bringing diesel cars to the U.S., GM’s product chief, Tom Stephens, said that GM has a wide portfolio of diesel engines and continually investigates bringing them stateside. But right now he thinks that diesels are better suited to heavy-duty trucks. A diesel engine under load offers a greater efficiency bump than what could typically be expected in a light-duty diesel car. “It’s also a question of priorities,” he says. “One of the things we look at is that we have a 96 percent dependence on conventional petroleum. The electrification of the automobile tends to take you away from that dependence; we think that’s a worthwhile strategy.” Of course, he’s talking about the Chevy Volt.
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Good article. I think diesel cars will have their own niche market. I doubt people who buy a Prius really care about payback period. I think the same would be true of diesel buyers. Moreover, I think a manufacturer would do quite well, to make a diesel that welcomes B100 (or, failing that, at least B50) without voiding the warranty.
“Reducing NOx to nitrogen and oxygen is much harder with a diesel engine because the exhaust is typically cooler and contains less oxygen compared to a gas engine.”
Just wanted to add that the reason for the above is efficiency: diesels convert more of the heat energy into mechanical energy leaving the exhaust cooler.
Good article. I think diesel cars will have their own niche market. I doubt people who buy a Prius really care about payback period. I think the same would be true of diesel buyers. Moreover, I think a manufacturer would do quite well, to make a diesel that welcomes B100 (or, failing that, at least B50) without voiding the warranty.
“Reducing NOx to nitrogen and oxygen is much harder with a diesel engine because the exhaust is typically cooler and contains less oxygen compared to a gas engine.”
Just wanted to add that the reason for the above is efficiency: diesels convert more of the heat energy into mechanical energy leaving the exhaust cooler.
Good article. I think diesel cars will have their own niche market. I doubt people who buy a Prius really care about payback period. I think the same would be true of diesel buyers. Moreover, I think a manufacturer would do quite well, to make a diesel that welcomes B100 (or, failing that, at least B50) without voiding the warranty.
“Reducing NOx to nitrogen and oxygen is much harder with a diesel engine because the exhaust is typically cooler and contains less oxygen compared to a gas engine.”
Just wanted to add that the reason for the above is efficiency: diesels convert more of the heat energy into mechanical energy leaving the exhaust cooler.
Very interesting and cleared up a few questions in my mind.
Very interesting and cleared up a few questions in my mind.