Audi has launched a clean diesel publicity campaign via an internet video called the "Truth in Diesel" touting that an engine which was "once a part of the problem is now a part of the solution." Saying that they've never "given up" on the development of diesel technology, Audi has made its compression-ignited offerings "cleaner, faster and stronger" than ever before. Also, the company says that if one-third of U.S. drivers operated a clean diesel, the country would displace the use of 1.5 million barrels of imported oil every day.

'It's a powerful message," says Gary Haer, spokesman for Renewable Energy Group in Ames, Iowa. "The public needs to understand that the diesel engines of today are not like the ones of the past-they're not as noisy and they're much more responsive. I own a diesel Jeep and I find that it's just as sporty in terms of acceleration and performance as any gasoline-powered vehicle."

Despite the current economic atmosphere, there will be efforts to produce more diesel models in the United States and build a stronger market for them.

Volkswagen, for instance, is building a manufacturing plant in Chattanooga, Tenn., which has an initial production capacity slated to be 150,000 vehicles, including a new midsize sedan designed specifically for the North American market. Production is scheduled to begin in early 2011. "A percentage of the models
we produce at this facility will be diesels," says Stuart Johnson, manager of engineering and environment at Volkswagen.

The German-based company is introducing a 3.0 liter V6 version of the Tourag and Audi Q7 in 2010. Also, the diesel Jetta and Golf models are making returns in the next model season after disappearing from the marketplace for several years. A host of federal and state incentives have made the Chattanooga plant possible. "There is money available from the National Clean Diesel Campaign for the retooling or outfitting of a factory if we produce diesel vehicles in this country," Johnson says. "We are building diesel Jettas in Mexico, which are North American Free Trade Agreement vehicles and for sale here."

In 2006, there was a drastic lowering of emissions standards which caused the company to pull these models out of showrooms to enhance their fuel economy and emissions performance. "It took quite a bit of effort to modify our designs to fulfill these requirements," Johnson says. "So we incorporated a particulate trap, a NOx catalyst, a different fuel injection system and a new exhaust recirculation system. We also changed the cylinders from two valves to four valves."

Weak Economy, Strong Competition, Strict Regulations
Last year there were 13 models announced by a dozen manufacturers at the '08 Detroit auto show, but economic conditions slowed the discussion of diesel a bit and some companies have said they're putting their diesel projects on hold for the moment-to weather this current economical storm and get the financial ship righted before they can make technological choices for the future. "Because of the current economic conditions, we have placed on indefinite hold the introduction of a 4.5L V8 version of the Duramax Diesel for the Chevrolet Silverado and GMC Sierra models, which were scheduled to be marketed in 2010," says Dave Barthmuss of General Motors Corp.

What the economy has done to the industry as a whole-to product lines and multiple power train technologies-there is much discussion and many questions about the economics of marketing diesel engines in light passenger vehicles. GM's offerings for 2010 will remain relatively status quo. Its line of Duramax and Turbo diesel models now includes the GMC Sierra, the Chevrolet Silverado 2500HD and 3500HD, as well as the G2500 and 3500 Express Cargo vans. The 2500 features a 6.6L, 32-valve V8 and a diesel particulate filter with a regeneration system.

Ford Motor Co. is also keeping its diesel offerings in the U.S. limited to heavy-duty trucks, the F-250 and F-350 series. "We've identified that diesel makes sense for large trucks in the U.S.," says Alan Hall, spokesman for Ford. "We do have several four-cylinder and six-cylinder models for sale in Europe, where their energy policy and emissions requirements are quite different than in the United States."

The U.S. has the strictest diesel regulations in the world, which several OEMS have told Biodiesel Magazine make it tough for them to expand their diesel portfolios. The new corporate average fuel economy (CAFE) standards set by the Obama administration for model year 2011 is 27.3 mpg for the light-duty fleet, which includes passenger cars and smaller trucks. The California Air Resources Board reported that its standard for model year 2011 is 26.7 mpg for the light duty fleet.

Diesel models are going to be a big part of Volkswagen's compliance plan. "A diesel engine is 30 percent better in terms of fuel efficiency and 20 percent better for carbon dioxide emissions, so it helps on both counts," Johnson says. While the new regulations are tough, Volkswagen nevertheless supports the federal CAFE program.

Daimler Corp., the manufacturer of Mercedes, is offering three Bluetec SUVs and an "all new" E350 Bluetec diesel sedan for the U.S. market in 2010. "Mercedes makes more clean diesels than any other manufacturer," says Jessica Altschul of Daimler USA. "So our diesel portfolio is certainly an aspect of our approach to meeting the EPA regulations for fuel economy and emissions performance of our fleets."

Experts say, however, that there is increased innovation in the gasoline sector-making a diesel-like combustion, gaining efficiency, turbo charging, downsizing-and ultimately closing the performance gap in terms of energy efficiency with diesel. "Our EcoBoost technology is similar to diesel with characteristics like direct injection and high pressure rails," Hall says. "The development of this technology has been more affordable for us to pursue than diesel, and that translates into savings for the consumer."

So diesel does have strong competition in terms of manufacturers' choices available to them related to complying with the CAFE requirements. Therefore, it's going to be more challenging for light-duty diesels in the coming years; but there are also plenty of opportunities. "We're very optimistic about the diesel market because, for one, we feel that it is an area that Volkswagen is an expert in," Johnson says. "New diesel engines are pretty sophisticated with great power, great torque and with new fuel economy standards we see this business having a real future in the U.S."

Haer notes that the mainstream consumer market has been one that's eluded biodiesel sales. "We've made great strides in developing sales in over-the-road trucking and other heavy-duty segments of the market, but passenger transport has not been a primary outlet for us," he says. "But with more diesel vehicles being introduced as a way to meet stricter government regulations, we see a great opportunity here."

Nicholas Zeman is an associate editor for Biodiesel Magazine. Reach him at (701) 738-4942 or nicholas.zeman@bbiinternational.com.