Caterpillar Inc., Peoria, Ill., has joined other U.S. diesel engine manufacturers in announcing its intention to meet 2007 U.S. Environmental Protection Agency emissions standards without the use of costly and complex SCR (Selective Catalytic Reduction) technology.

SCR is an engine aftertreatment technology that requires the availability of an ammonia-based urea fluid to be injected into the exhaust to reduce nitrogen oxide (NOx) emissions in diesel engines. Cat says SCR requires a special production and distribution infrastructure for delivery of this additional fluid to the vehicle, adding another level of complexity for truck customers. Moreover, there are questions related to the significant challenges associated with enforcing the use of urea in on-highway trucks and buses.
"Our goal is to provide the North American trucking industry with engines that meet EPA's 2007 regulations without sacrificing performance or fuel efficiency," said Richard L. Thompson, Caterpillar group president with responsibility for the company's engine division. "We can meet EPA's 2007 regulations and customer needs without SCR. Our ACERT technology provides a significant breakthrough because our customers will avoid the burden of complex and costly technologies associated with SCR.
"Caterpillar, like other engine manufacturers, successfully uses SCR to reduce emissions in stationary generator sets," Thompson noted. "However, our engineers do not believe that SCR is the best emissions reduction technology choice in the United States for on-highway mobile applications. We encourage the EPA to remain technology neutral, and avoid mandating SCR as a future emissions reduction technology."
Diesel engine manufacturers must commit to an emissions reduction technology path well in advance of 2007 production that meets aggressive customer standards for performance, cost effectiveness, quality, reliability, and durability.
More information is available at www.cat.com.