Here’s a good slide from a Honda presentation at the Department of Energy’s DEER (Diesel Engine Emissions Reduction) conference held last month. It clearly shows how much diesel is better than gasoline when it comes to fuel economy and miles per gallon. Only the gasoline direct injection vehciles come close but there are (a) very few of them available, and (b) their emission levels, esp particulate emission levels, are almost as high as diesels.
Diesels are only now starting to make some what of a splash in the USA, even thoguh nearly 50% of all cars sold in Europe are already diesels. Ford, GM, Chrysler, VW, Mercedes all sell diesels in Europe, but have not brought them to the US as yet. Mercedes, and now Honda, have recently announced diesel vehicles that can finally meet the stringent Tier 2 Bin 8 and Tier 2 Bin 5 regulations in the US (its just industry jargon to say that strictest regulations are in California and then followed by EPA in the rest of the states). Diesel engines last million miles and provide great fuel economy. According to an estimate by CARB (California Air Resources Board), diesel engines can cost about $750 more than gasoline equivlents, but the investment is paid back in 3 years in fuel economy savings. A hybrid costs much more and the investment payback period is 6 years.
If the diesel emission controls ystems can be made to work in the US (and at a reasonable price), diesel certainly carry a good future, at least for th enext 10-20 years before plug-in hybrids and/or fuel cell vehicles start to prove themselves commercially viable. I look forward to seeing more diesels on the road. Right now its just prevalent in the light truck and heavy duty categories, but hopefully lighty duty car category will also see some snazzy diesels very soon.