'New' diesels boost mileage, reduce soot
Another trend making diesel cars popular among the environmentalist crowds is the increasing availability of biodiesel.
Biodiesel is a blend of petroleum-based diesel and a refined vegetable oil -- typically soybean oil. Marketed as B5 or B10, meaning 5 percent or 10 percent vegetable oil, nearly every manufacturer has approved the fuel in their diesel engines.
What's more, the biodiesel burns at a much higher efficiency rate than ethanol. This is attractive both to the environmentalists who advocate less carbon emissions, but also among many right-wing advocates who wouldn't otherwise align themselves with the green movement, but who want to push for less dependence on foreign oil.
Hobbyists and do-it-yourselfers have found an even less petroleum-dependent solution with their diesel-powered engines. Some are buying equipment to manufacture small batches of bioidiesel at home by combining waste vegetable oil from restaurants and another fuel stock, typically methanol. Others are converting their diesel engines to run completely on waste vegetable oil.
And while both methods could
yield some fuel savings -- often just pennies
per gallon -- using anything except diesel
or biodiesel marketed by a traditional gas
station may raise the ire of the automakers.
"The manufacturers really don't like
that," Linkov says. "Using those
homemade options will typically void your
Because of that, most people
tinkering with vegetable oil-based fuels are
doing so with older models. "You don't
think people will do that with their $60,000
Mercedes-Benz," Linkov says.
One problem plaguing biodiesel, and to some extent, traditional diesel fuel, is the lack of availability.
While diesel isn't nearly as hard to find as its biodiesel counterpart, it certainly isn't available at every corner gas station. On the other hand, diesel is becoming more universally available than in years past.
Reed likened the problem of finding diesel to the quest many people go on to find the best deal on gasoline. If you are near your home, you will know which stations offer it, but it may be a slight problem in a strange part of town or on a road trip.
But, on the bright side, when you do find diesel, it has tended to be less expensive than gasoline over the past year or so.
Biodiesel is another matter. To help consumers on their search, the national biodiesel board publishes a list of every station in the nation that offers the alternative fuel on its Web site.