Issue link: https://read.dmtmag.com/i/671314
|Tomorrow's Trucks | What's in store for emissions and NOx control? By Jason Cannon 6 www.studentdriverplacement.com May '16 T he EPA and NHTSA, in collabo- ra on with the California Air Resources Board (CARB), plan to extend the Heavy-Duty Na onal Program be- yond model year 2018, to further reduce fuel consump on and reduce CO2 emissions by up to 4 percent compared to Phase 1 before 2028. "As people get more and more fi xated about CO2 or fuel economy standards, it's also going to raise a question," Dr. Steve Golden, chief technology offi cer for Clean Diesel Technologies, Inc., says. "This beau- tiful over-engineered emissions sys- tem, how's it going to have to evolve to be consistent with the engine calibration changing, or [to get] better fuel economy, because all kinds of things have to change about engine design to get better fuel economy. How does that impact the next gen- eration after treatment system?" Phase II doesn't mandate a spe- cifi c new engine technology, and en- gine OEMs are free to take a variety of paths and methods to meet the effi ciency gain goal. Jackie Yeager, Cummins' global energy policy director, says the company is already mulling how it will rise to meet Phase II at benchmarks in 2021, 2024 and 2027. "We've talked about building on the archi- tecture you see today with our engines," she says, "with EGR, DPF and SCR. That all stays, of course, because you have to meet NOx." Yeager says making the same kind of base engine improvements – like combustion optimization, better air handling, reducing friction, reducing parasitic loads and after treatment effi ciency improvement – will be a big part of the strategy, as will looking at the benefi ts and feasibility of waste heat recovery. "That's something the EPA looked at [when setting its Phase II goals]," she says. Golden adds fuel effi ciency re- quirements included in Phase II will challenge engine builders seeking to preserve low NOx emissions. "There are signifi cant tradeoffs in getting lower NOx," he says, noting a higher combustion temperature helps