External combustion

| April 30, 2009

Proponents of the two 2010-compliant heavy-duty engine technologies battled at press events during the Mid-America Trucking Show in Louisville, Ky., in March.

The alternatives will reduce NOx emissions to meet the 2010 U.S. Environmental Protection Agency regulations.

Navistar, the lone engine maker not using selective catalytic reduction to meet the new regulations, lobbed shots at its competitors during an event where it showcased its new 15-liter MaxxForce engine.

SCR involves complexity, payload, packaging, weight issues and hassles, said Dee Kapur, president of International’s Truck Group. “It means adding five new major emission critical components.”

Navistar’s solution – enhanced exhaust gas recirculation – means no added hardware and no new, complex electrical system, he said. For medium and severe-service, advanced EGR is “a no brainer,” he said. Navistar’s 2010 engines will produce 0.5 grams of NOx and will use EPA credits previously earned by exceeding EPA emissions goals to achieve the required 0.2-gram limit.

“SCR is not a new development,” said Chris Patterson, outgoing president and CEO of Daimler Trucks North America, during a panel discussion, in which SCR proponents sought to dispel what they deemed “misinformation” about SCR. Patterson cited the more than 200,000 SCR-equipped trucks Daimler has operating in Europe. The technology “has already saved our customers nearly half a billion dollars in fuel costs, compared to other technologies,” he said.

All engine makers use EGR today, said Denny Slagle, president and CEO of Mack Trucks. “It generates a lot of heat and puts stress on the engine,” he said. “We manage well today, but we’ve reached the limit of what we can do using EGR.”

Engine makers on the panel – Daimler, Mack, Volvo and Cummins – cited fuel savings of around 5 percent compared to 2007 technology engines. Navistar officials concede that the company’s advanced EGR engines can’t match the fuel economy of the SCR-equipped engines of its competitors, but they argue that buyers must consider the fuel economy of the overall package and the benefits of avoiding SCR.

One of Navistar’s biggest arguments against SCR is that for the first time it makes the owner and driver accountable for emissions, Kapur said, because diesel exhaust fluid must be added periodically to maintain appropriate emissions levels. That initially was a concern for the U.S. Environmental Protection Agency, as well, said Byron Bunker, with EPA’s Office of Transportation and Air Quality, “but the industry has done an absolutely fantastic job of answering that concern.”

Bunker said EPA has not endorsed any technology to meet the 2010 standards.

The DEF itself was a source of debate. Navistar officials said the fluid freezes at 12 degrees Fahrenheit and can become a toxic ammonia gas at 122 degrees. But Barry Lonsdale, president of Terra Environmental Technologies, a supplier of the urea used in DEF, told panel attendees that the fluid is non-hazardous, based on Occupational Safety and Health Administration criteria.

“Let’s remember diesel fuel is a hazardous substance,” Patterson noted. DEF “is relatively benign.” And if the DEF is altered by temperature or other factors, “it won’t affect engine performance or fuel economy and won’t harm the after-treatment or engine,” he said.

Referring to media reports that DEF will be available at 500 U.S. fueling stations, Kapur expressed concern about adequate availability. Representatives from Pilot Travel Centers and TA/Petro who participated in the panel sought to allay any concerns. Both companies said they will begin rollout of DEF this year.

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