By Frederick Kiel, Staff Reporter
This story appears in the Nov. 24 print edition of Transport Topics. Click here to subscribe today.
Navistar International Corp. will use federal emission credits to enable its new Class 8 engine to meet 2010 federal emission standards, although the engine could be set up to comply with the regulation without the credits, a Navistar executive said.
Navistar’s proprietary big-bore engine will use exhaust gas recirculation to meet the drastically reduced nitrogen oxides emissions level mandated by 2010, rather than the selective catalytic reduction system employed by all other engine makers.
Timothy Shick, director of marketing for Navistar’s Engine Group, told Transport Topics that using emission credits will enable it to run higher NOx levels for about two years and use the time to “fine-tune” its EGR system.
Other engine manufacturers, including Cummins Inc. — which supplies engines for Navistar’s International trucks — have said they will rely on SCR technology for 2010 because it offers greater fuel efficiency. However, Shick said the cost of the urea solution that SCR requires would offset the fuel-economy gains.
The Environmental Protection Agency’s rules allow a manufacturer to save credits during years when its engines exceed existing emission standards and apply them to years when its engines don’t meet the required levels.
“It is correct that Navistar will not limit NOx emissions to the federally mandated limit of 0.2 grams per brake horsepower hour, as of January 2010,” Shick told TT. “We can meet 0.2 right now and with good performance if we wanted to. All of our volume engines today are operating at lower than ’07 engine requirements. That is how we’re earning the credits.”
Shick said that Navistar planned to use the credits, probably over two years, to “calibrate” its engine while it learns more about the engine’s operation to achieve optimum fuel efficiency and performance while meeting the NOx mandate.
He said Navistar’s program will emit less pollution overall because EPA permits companies to use the credits only at a discounted level, which he estimated to be between 60% and 70% in 2010 for each credit earned earlier.
“Navistar has been building EGR engines since 2004,” Shick said. “Our EGR engines on the road now have lower overall emissions than federal 2007 regulations call for and have lower emissions, including NOx, than the new MAN big-bore engine with EGR introduced this year.”
Navistar is producing a Class 8 engine by adding its own electronics, fuel-induction and exhaust systems to a basic engine from German manufacturer MAN.
Shick said Navistar would use EGR in 2010 to avoid upkeep and maintenance problems in 2010. He said Navistar’s “enhanced” EGR system would meet 2010 NOx levels without new components for 2010.
The Clean Air Act requires diesel engines to drastically cut both NOx and particulate matter, or soot.
EPA’s 2007 emissions rule cut soot standards, forcing engine makers to install diesel particulate filters, which cost several thousand dollars and require regular maintenance.
EPA’s 2010 standards cut allows NOx emission at nearly negligible levels.
SCR uses a converter in the exhaust system that takes out NOx, but it requires injection of a chemical catalyst: a pure form of urea and water called Diesel Exhaust Fluid.
“Our 2010 engines will be fuel neutral to where we are today,” Shick said. “The SCR people will argue that they will be able to use less fuel, and we don’t dispute that. We have tested SCR for some time, but we have seen a one-for-one trade-off in the amount of fuel saved versus the amount of urea used to reduce NOx.”
Chuck Blake, technical sales support manager of Detroit Diesel Corp., whose 2010 engines — produced for Daimler’s Freightliner and Western Star trucks— will use SCR, disputed Shick’s statements about urea costs.
“Overall, SCR engines will use 5% less diesel than EGR, overset by a 2% takeaway from urea, but urea will cost two thirds less,” Blake said.
Shick responded that the distribution system for urea “is not currently mature and urea is extremely expensive in North America today.”
Spokesmen for both subsidiaries of global truck maker Volvo AB — Mack Trucks Inc. and Volvo Trucks North America — told TT that their engines with SCR can meet the new regulations without using credits.
A spokesman for Paccar Inc., which will use SCR engines in its 2010 Peterbilt and Kenworth brands, said they will not use credits.