Sources: U.S. Environmental Protection Agency; CP staff
Through its just-announced Cleaner Trucks Initiative (CTI), EPA aims to further decrease nitrogen oxide (NOx) emissions from on-highway heavy-duty trucks and update a current engine exhaust standard in an early-2020 rulemaking. Set in 2001, the standard culminated in 2010 with a 0.2-gram brake-horsepower-hour NOx threshold for which engine manufacturers deployed selective catalytic reduction equipment and urea-based diesel exhaust fluid.
CTI will see the agency streamline compliance and certification requirements through a “deregulatory” focus on onboard diagnostic requirements; cost-effective means of reassuring compliance by using modern and advanced technologies; deterioration factor testing process; and, concerns regarding annual engine family recertification.
“The Initiative will help modernize heavy-duty truck engines, improving their efficiency and providing cleaner air for all Americans,” said Acting EPA Administrator Andrew Wheeler, who unveiled the CTI in an early-November gathering with the American Trucking Associations, equipment manufacturers and other industry stakeholders. “The U.S. has made major reductions in NOx emissions, but it’s been nearly 20 years since EPA updated these standards. Through rulemaking and a comprehensive review of existing requirements, we will capitalize on these gains and incentivize new technologies to ensure our heavy-duty trucks are clean and remain a competitive method of transportation.”
“[CTI] makes clear that reducing NOx emissions from heavy-duty vehicles is a clean air priority for this administration,” added EPA Office of Air and Radiation Assistant Administrator Bill Wehrum.
NOx emissions dropped by more than 40 percent from 2007 to 2017, owing partly to the advent of SCR exhaust aftertreatment on heavy-duty trucks. But there is more work to be done, contends EPA, citing estimates that such vehicles will be responsible for one-third of transportation sector NOx emissions in 2025. The agency expects that any update to the standards will result in significant mobile source NOx reductions, assisting communities across the country in ozone and particulate matter standards attainment.