EPA Eyes Further NOx Reductions from Diesel Engines  

Share

The U.S. Environmental Protection Agency EPA is eyeing another round of federal regulations aimed at further tightening heavy-duty truck emissions and to create a so-called “50-state program” that harmonizes emissions standards nationally, reports CCJ magazine.

EPA Administrator Andrew Wheeler on Monday announced an advanced notice of proposed rulemaking (ANPRM), part of the Trump EPA’s Cleaner Trucks Initiative, that seeks input from the public and from trucking industry stakeholders about the next phase of regulations meant to further curb output of nitrogen oxide (NOx) and other air pollutants, Wheeler said.

“The U.S. has made major reductions in NOx emissions, but through this initiative we will continue to reduce emissions, while spurring innovative new technologies, ensuring heavy-duty trucks are clean and remain a competitive method of transportation,” Wheeler said.

EPA credits previous rounds of emissions regulations and technologies like exhaust aftertreatment in post-2010 diesel engines with reducing heavy-duty truck exhaust emissions of NOx and particulate matter by 90%. Regardless, it appears the EPA is ready to compel manufacturers to go further.

EPA says it has identified high NOx emissions during engine warmup and idling periods and when emissions controls deteriorate over time, as well as in crankcases that can emit emissions. These areas, as well as an overhaul of engine certification procedures, are targets for the next phase of emissions standards, according to the 97-page ANPRM posted online Monday by EPA.

Nearly half of the U.S. truck fleet is powered by post-2010 emissions technology, says CCJ.

Once the ANPRM is published in the Federal Register stakeholders and the public can comment for 30 days. In his address Monday — and in the ANPRM — EPA says it intends to work more closely with manufacturers and other industry stakeholders to develop the new regulations. However, any formal regulations stemming from the ANPRM are likely years away, as rulemakings generally take several years to move from the ANPRM stage to a final, published rule, reports CCJ.

“Heavy-duty vehicles continue to be a significant source of NOx emissions now and into the future. While the mobile source NOx inventory is projected to decrease over time, recent emissions modeling indicates that heavy-duty vehicles will continue to be one of the largest contributors to mobile source NOx emissions nationwide in 2028,” EPA said in a statement.

Other areas EPA says it seeks input on are: emissions control and monitoring technologies; durability of emissions control systems like exhaust aftertreatment; fuel quality; hybrid, battery-electric power, fuel cell and other alternative fuels; emissions testing and certification procedures; “in-use” standards (which would require vehicles to meet emissions standards at certain mileage thresholds); emissions education and incentives; longer warranties for emissions control systems and more.

The American Trucking Associations applauded EPA’s proposal.

“ATA is committed to continuing to work closely with EPA on developing the next generation of low-NOx emitting trucks through the Cleaner Trucks Initiative. To this end, the trucking industry seeks one national, harmonized NOx emissions standard that will result in positive environmental progress while not compromising truck performance and delivery of the nation’s goods,” said ATA’s Bill Sullivan, executive VP of advocacy.

Scroll to Top