By Sholnn Freeman
Washington Post Staff Writer
Thursday, October 19, 2006
Steering the big E320 sedan, Mercedes-Benz engineer Rudolf W. Thom comes around a corner and gently presses down on the accelerator, revealing the faint yet familiar sound of a diesel engine.
"If you compare this diesel to the diesels of the past, can you hear this diesel?" he said. "Can you smell this diesel? It is not like the bad diesels of the past."
The E320 gets 35 miles per gallon, 30 percent better than the comparable gasoline version of the car. Because of favorable tax policies in Europe, diesels have taken off there in the past 15 years, accounting for 50 percent of the new models sold each year. In the United States, development of the market has lagged because of government concerns over what the fuel does to air quality; diesel vehicles make up just 3.2 percent of the market.
The dynamics began to shift this week. On Sunday, the Environmental Protection Agency began requiring refiners and fuel importers to reduce the sulfur content in diesel fuel by 97 percent. The low-sulfur fuel opens the door to a new generation of clean diesel cars, and automakers are moving to bring out more models in the U.S. market.
The change promises to significantly cut air pollution caused by diesel emissions. Regulators say high concentrations of sulfur in the old diesel fuel poison the engine systems that clean exhaust of harmful pollutants. The biggest concern is particulate matter, one of the byproducts of engine combustion, said Margo Oge, director of the EPA's office of transportation and air quality. The particles are a fraction of the size of a human hair. Public health advocates have described the particles as tiny spaceships that dive into the respiratory system when people inhale, damaging the lining of the lungs.
Particles from diesel emissions are classified by the government as a potential carcinogen and are linked to premature deaths, heart attacks to respiratory illness.
Mark MacLeod, director of special projects for Environmental Defense, an advocacy group, said the new EPA rules are expected to prevent about 8,000 premature deaths each year, 1.5 million lost work days and 360,000 asthma attacks.
Detroit automakers have pledged to expand diesel offerings, particularly in pickup trucks. J.D. Power and Associates projects that the diesel share of light-vehicle sales is expected to increase to more than 10 percent by the middle of the next decade from 3.2 percent in 2005. Japanese automakers are also stepping up development of diesel technology.
As U.S. consumers become more sensitive to higher gas prices, German automakers view diesels as their best weapon in the U.S. market to counter strong sales of gas-electric hybrids. They claim a long history of innovation in diesel technology. Mercedes sold large numbers of diesels in the United States in the 1980s. Volkswagen AG for years has sold diesel versions of its popular cars, including the Jetta and the Beetle.
In this country, automakers have shied away from diesels since the early 1980s. GM produced a diesel engine during that decade that was used throughout its lineup. But auto analysts say the engine had problems with piston rings and cylinder combustion. The cars were smoky, loud and slow. Some diesels wouldn't start in cold weather. Mercedes models of that era also are remembered as being slow and noisy, helping cause consumers to sour on diesel technology.
"Consequently, all the Big Three have been afraid to do diesel," said Casey Selecman, manager of North American powertrain forecasts at CSM Worldwide. "They believe the American public still sees diesels that way. Now they have this great competency in Europe. All the things that plagued the diesels in the early '80s are now gone."
At Mercedes, marketers have developed the name Bluetec for the company's diesel engines in the United States to try to cleanse them of persistent negative perceptions. The company said other German automakers may use the name to sell diesel technology.
"We have to make a mind-set change because the diesel name is damaged," Thom said.