Technology Levers for Meeting 2027 NOx and CO ₂ Regulations

Abstract

<div class="section abstract"><div class="htmlview paragraph">Commercial vehicles require fast aftertreatment heat-up to move the SCR catalyst into the most efficient temperature range to meet upcoming NO<sub>X</sub> regulations while minimizing CO<sub>2</sub>. The focus of this paper is to identify the technology levers when used independently and also together for the purpose of NO<sub>X</sub> and CO<sub>2</sub> reduction toward achieving 2027 emissions levels while remaining CO<sub>2</sub> neutral or better. A series of independent levers including cylinder deactivation, LO-SCR, electric aftertreatment heating and fuel burner technologies were explored. All fell short for meeting the 2027 CARB transient emission targets when used independently. However, the combinations of two of these levers were shown to approach the goal of transient emissions with one configuration meeting the requirement. Finally, the combination of three independent levers were shown to achieve 40% margin for meeting 2027 transient NOx emissions while remaining CO<sub>2</sub> neutral. These independent levers and combinations were also quantified for meeting the new Low Load Cycle. This paper shows which combinations of technologies meets both the transient emission cycles and low load cycles for NOx with adequate margin while also saving CO<sub>2</sub>.</div></div>