U.S. to Tighten Heavy-duty Emissions


U.S. to Tighten Heavy-duty Emissions
© Photo courtesy of Weston Star

The United States Environmental Protection Agency unveiled on Monday proposals to implement more stringent nitrogen oxide emissions limits on heavy-duty trucks beginning with model year 2027 vehicles.

The first step in an effort to reduce heavy-duty NOx emissions caps for the first time in two decades, the initiative lays out two options – one of which would cut NOx emissions by 47% by 2045, the other implementing a 60% reduction by that date.

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The proposed rules would lean on use of new emissions control technologies for internal combustion engines, rather than a switch to electric vehicles – a course that some environmental groups criticized as too weak.

It would also increase the travel distances and number of years that heavy-duty vehicles are required to meet the standards – tackling a long-time criticism that existing regulations allow older trucks to pollute too much.

This week’s proposal would also lower greenhouse gas emission limits for several categories of trucks, including buses, commercial delivery trucks and heavy-duty tractors used for short hauls – again beginning in 2027. Officials said these rules would cause prices for those vehicles to rise approximately $4,000 per unit and acknowledged that they are intended to encourage a shift to electric vehicles.

EPA said it intends to introduce additional regulations applying to all heavy-duty trucks – including some on particulate matter and greenhouse gases – by 2030.

NOx emissions limits on vehicles with internal combustion engines affect engine oil performance demands by requiring oils to accommodate emissions control technologies. Technologies implemented to date – such as selective catalytic reduction and exhaust gas recirculation – have required lubricants to tolerate higher acid levels and more soot and led to lower caps on levels of chemicals such as phosphorus.

The proposals must undergo a public comment period before final regulations can be adopted. EPA has not yet announced a schedule for public comment, but officials said they aim to adopt final rules by the end of the this year.

Several industry groups said they welcomed the agency’s proposal but said they will encourage it to write a final rule that does not add too much to the cost of new trucks.

“We look forward to working with EPA to ensure that the final version of today’s rule is practical, technically feasible, cost-effective, and will result in the necessary fleet turnover to achieve the nation’s environmental objectives,” EMA President Jed Mandel said in a news release.