Real world emissions from Vehicles

Research Project, 2021 – 2022

To reach a sustainable transport system, “near zero” local emissions is need in urban areas. The most important local emissions are NOx and particulate matter (PM) emissions. Since modern exhaust gas aftertreatment systems (EATS) are more efficient, the tailpipe emissions will be comparable to many other sources including wear particles. Also, since hybridization is effective to reduce (global) CO2 emissions, the tailpipe emissions will be even lower. Moreover, since the engine will operate intermittently, the NOx emissions may increase due to low EATS temperatures. In this context, there is a significant gap of knowledge on how different propulsion systems contributes to the local emissions and to human health. In this new collaboration the division of Combustion and Propulsion Systems (CaPS) at M2 and the division of Microwave and Optical Remote sensing (MOF) at SEE will combine to address this gap. A Portable Emission Measurement System (PEMS) will be applied on vehicles to measure their tailpipe emissions during driving conditions. In parallel, a measurement vehicle equipped with fast state of the art instrumentation, will be used to chase the vehicle equipped with PEMS measuring the exhaust a few meters downwind while driving. In particular differences in tailpipe and downwind VOC emissions will be analyzed. This new methodology will be applied to measure a wide variety of vehicles to analyze their real-world emissions and compare with the manufacturer specifications and investigate the evolution of air pollutants after leaving the tailpipe.