Characterization of on-road emissions of heavy-duty vehicles under China VI

The implementation of China VI emission standards for heavy-duty vehicles (HDVs) necessitates a thorough evaluation of their real-world emission performance beyond conventional laboratory certification procedures. This study assesses the on-road emissions of China VI-compliant HDVs by collecting and analyzing Portable Emissions Measurement System (PEMS) data from 40 vehicles across various categories. The results show that while work-based Moving Average Window (MAW) emission measurements meet China VI regulatory limits, the application of European Union (EU) cold-start inclusion criteria leads to a 100 % to 150 % increase in NOx emissions for N2 and N3 vehicle classes. Additionally, the proportion of low-load work windows for N2 vehicles ranges from 45% to 85%, whereas for N3 vehicles, this proportion typically remains below 50 %. Consequently, the power threshold defining the valid work window significantly impacts NOx emissions in N2 category vehicles. In contrast, compared to NOx emissions, the experimental conditions and calculation methodologies employed in PEMS testing exhibit relatively minor effects on the emission outcomes for carbon monoxide (CO) and particle number (PN). 1. NO X , CO, CO 2 , PN emissions data of 40 China VI HDVs were analyzed. 2. The emissions of all vehicles meet China VI emission limits. 3. Cold-start operations constitute a substantial share of total NO X emissions . 4. Most of the NO X emissions come from the vehicle's urban operation 5. Vehicle PN emissions are very close in the different route operations.