Towards improving air quality, efforts are being made to reduce pollutant emissions from traffic below current legislated standards (Euro 6/7), aiming to achieve pollutant emissions of ultra-low and even zero-impact level. Diesel vehicles remain a primal source of air quality deterioration caused by the transportation sector. Although various diesel powertrain technologies have been intensively investigated in this context, a study that approaches the design of zero-impact emission diesel vehicles holistically, taking into consideration all possible boundary conditions from the vehicle and the air quality perspectives, is still missing. Against this background, this study presents various zero-impact emission powertrain solutions on an N1 Class III light-duty commercial vehicle with a diesel internal combustion engine. To achieve this, the “Zero-Impact Emission” term is firstly defined as the vehicle emission level that ensures irrelevant contribution to air quality. Next, a universal method to test the compliance of an internal combustion engine powered vehicle with the defined zero-impact emission requirements is identified. To investigate, if the studied diesel vehicle can be labeled as equivalent to its battery electric version in respect to their impact on air quality, the focus of this work is on real-driving tailpipe NOx emissions. These originate clearly only from the internal combustion engine, hence identifying the battery electric vehicle as zero NOx emission vehicle by definition. In the following, an ultra-low emission vehicle concept is specified in accordance with the European Commission’s 2022 Euro 7 regulation proposal as a potential technology reference for the market-representative diesel powertrain of the future. These interim emission requirements were in many terms more ambitious than the 2024 Euro 7 update and release. The vehicle is found to be able to achieve zero-impact NOx emission compliance in 67 % of the considered test cases that combined adversely vehicle emission and air quality aspects. To achieve zero-impact NOx emissions in all test cases, further advanced emission solutions are essential on the reference vehicle. In congested urban areas, the use of an exhaust gas aftertreatment system preheating device with at least 20 kW of power for 1 min is required. In high-traffic highway situations, an underfloor SCR with a minimum volume of 12 l or a restriction of vehicle’s top speed at 130 km/h is required.
Theodoros Kossioris (Thu,) studied this question.