Team Audi’s victory at 24 Hours of LeMans Sunday with a car powered by a TDI diesel engine again shines a light on diesel engines as an alternative to regular gas or hybrid gas/electric vehicles.
Though cars and trucks running on diesel fuel remain a relatively small percentage of new cars and trucks sold in the U.S., increasing sales of such vehicles by German car companies in the U.S. points to a potentially rosier future.
And the continued success of diesels at LeMans keeps bringing attention back to the powerful fuel. Audi has won LeMans with diesel engines every year since 2006 except 2009, when Puegot won with a diesel-fueled sports car.
Audi presently sells two diesel vehicles to consumers in the U.S.—the A3 TDI and Q7 TDI. In the next two years, though, it is expected to introduce three more—diesel versions of the A6, A8 and Q5.
“We are making a lot of headway in educating U.S. car buyers about clean diesel,” says Jonathan Browning, CEO of Volkswagen of America. Volkswagen said 22% of its total U.S. sales, or 56,500, in 2010 were clean diesel “TDI” vehicles. When the company launches its new redesigned Passat family sedan in the Fall, it projects that as many as 40%, or about 50,000 it plans to build in 2012, could be run on diesel.
What you need to know about “clean diesel”
Diesel was re-named “clean diesel” a few years ago when the standards for diesel fuel changed to contain “low sulfur.” That change in the fuel, plus on-board systems that capture a lot of the tailpipe particulates, means that burning diesel fuel in a state-of-the-art passenger car or pickup truck is a lot cleaner than, say, burning the fuel in a tractor-trailer truck that doesn’t have the same on board systems.
Fuel economy advantages vary with diesel passenger vehicles from 20% to about 30%. For example, the VW Jetta TDI (diesel) gets 30 mpg city/42 mpg highway for a combined 34 mpg, while the gas version (automatic transmission) of the same car gets 24 mpg city/31 highway for a combined 27 mpg. The TDI is 26% more fuel efficient. But if a driver logs a lot more highway miles than suburban commuting, the diesel’s highway mileage gives them a 35% gain.
The arithmetic for judging if a diesel is for you, though, is a bit more complicated. First, a Jetta TDI with an auto/manual transmission stickers at about $24,095 without extra features and destination charges. A comparable gas version costs $20,645 before you add features and the destination charges.
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