Emissions continues to be the most significant issue affecting our engine development,” John Campbell declares right off the bat.
Conceding there are “different ways to solve the emissions puzzle,” Campbell says Cat has elected to put its Advanced Combustion Emissions Reduction Technology (ACERT) program into play and will not be going down the cooled-EGR road other manufacturers have elected to pursue.
He describes ACERT as an “advanced fuel system and combustion technology solution” that will maintain current reliability and durability standards while minimizing the cost impact on both engine and vehicle systems.
“Using ACERT will allow us to meet EPA's goals for emissions while providing benefits to both truck owners and truck manufacturers,” Campbell says. “Used with the next generation of our HEUI [Hydraulically actuated, Electronically controlled Unit Injector] fuel system and integrated with the latest in Cat electronics, ACERT will reduce engine emissions where they are created — in the combustion chamber. However, aftertreatment will also be required.”
According to Campbell, ACERT's benefits include allowing vehicle designers to continue using current cooling packages (rather than the beefed-up systems expected for cooled-EGR engines), and delivering fuel economy comparable to current Cat engines. He also says ACERT engines will be some 50% quieter than today's comparable engines.
He says all Cat's midsize and heavy-duty truck engines will employ the new patented system to reach the '02 emissions limits without unduly compromising either engine reliability or durability.
According to Campbell, ACERT will be integrated with the HEUI fuel system on all its midrange and heavy-duty truck engines by the beginning of the fourth quarter of 2003. ACERT will not be retrofitted to current engines.
Of course, that means ACERT engines won't be on the market when the next emissions deadline — October 1, 2002 — actually hits. But Cat won't be asking EPA for any extensions. “We are going to make all of our commitments to EPA,” Campbell states. “We will work within the flexibility of agreements we have in place with EPA.”
While that may mean cashing in some emissions “credits” the manufacturer has banked, Campbell states that Cat is working with EPA to “find the method to provide product in that time frame,” spanning roughly from October '02 to the following fall. He says he expects Cat to “use current product with some modifications” to fully cover its bases.
“We don't have a final '02 product design committed to our OEM partners yet,” Campbell adds. “We know we will not use cooled EGR, and I can say we are considering various types of aftertreatment.”
But according to Campbell, the really big news is that both ACERT and aftertreatment will also serve as the “building blocks” to enable Cat to meet EPA's even-stricter '07 emissions limits.
“For '07,” he says, “both NOx and particulates will have to be cut significantly. The NOx limit will be 0.2 grams, down from today's 4.0. Particulates will be cut by 90%, going from 0.1 gram to just 0.01 gram.”
As for potential '07 aftertreatment solutions, Campbell advises that a “leading contender” is SCR (selective catalytic reduction), an approach used in Europe. “SCR uses a urea solution to address NOx,” he says.
“We are already using SCR on diesel-fired electric-generating systems used in nonattainment areas of the country,” Campbell notes.
Name: John Campbell, director of truck engine products, Caterpillar Truck Engine Div., Peoria, IL
Background: A Cat man since 1966, Campbell has worked in manufacturing, quality control and product development. He led development of the C-15/C-16 engine line and had a key role in developing the 3400, C-10 and C-12 engines. Campbell holds a BA in management from Sangamon State University and an MBA from the University of Illinois. He is a member of the American Society for Quality Control.
Each month this column looks at emerging truck technology issues through the eyes of a leading engineer.