The world’s first attempt to measure particulate matter (PM) emissions generated by not only engine combustion but also the wearing down of brakes and tires is complete.
The Korea Institute of Machinery and Materials (KIMM), an institute under the jurisdiction of the Ministry of Science and ICT, announced that it has succeeded in an integrated experimental measurement of exhaust (engine combustion) and non-exhaust (tire and brake wear, road wear, and re-suspended road dust) emissions from the internal combustion engine and electric vehicles.
Until now, research on measuring the amount of non-exhaust PM emissions or identifying the phenomenon has rarely been conducted except for brake wear PM emissions. When estimating total PM emissions, superficial methods have used emission factors corresponding to each emission source listed in the national emission inventory.
It is the world’s first attempt to measure the total PM emissions according to vehicle type and sources through integrated experimental measurements. The result of this study will be used to identify the cause of the non-exhaust emissions from internal combustion engines and electric vehicles and to develop guidelines for governmental policies to mitigate traffic-related PM emissions.
The comparison of total PM emissions emitted from internal combustion engines and electric vehicles. The measurement of PM emissions of internal combustion engines and electric vehicles with 90% of regenerative braking intensity, the PM10 emissions of gasoline vehicles, diesel vehicles, and electric vehicles were 42.3 mg/km, 43.2 mg/km, and 47.7 mg/km, respectively. PM2.5 emissions were 14.5 mg/km for gasoline vehicles, 14.1 mg/km for diesel vehicles, and 13.9 mg/km for electric vehicles. Under the 50% of regenerative braking intensity, the electric vehicle has emitted up to 15% more PM10 emissions compared to the internal combustion engine vehicles. However, the study estimates that PM10 and PM2.5 emissions of an electric vehicles are reduced by 15% and 50%, respectively, compared to the internal combustion engine vehicles, when we consider the secondary PM emission from engine combustion. As mentioned above, the current exhaust system in internal combustion engine vehicles has emitted significantly lower PM emissions with the help of modern technological advancements in engine combustion and after-treatment devices. The study found that more than 90% of PM emissions from internal combustion engine vehicles were originated from non-exhaust sources. © The Korea Institute of Machinery and Materials (KIMM)
The brake wear simulator, tire wear simulator, and a mobile road dust measurement vehicle used to measure non-exhaust emissions. For this research, the current technological instruments are applied to accurately measure non-exhaust emissions according to vehicle type. Tire wear simulator, brake wear simulator, and mobile road dust measurement vehicle were utilized to measure the PM emissions from tire wear, brake wear and resuspension of road dust. © The Korea Institute of Machinery and Materials (KIMM)
Seokhwan Lee and his research team in the Department of Mobility Power Research at the KIMM Institute of Carbon Neutral Energy Machinery conducted an integrated experiment and measurement of PM emissions according to the powertrain type for compact SUVs using an in-house developed tire wear simulator, brake wear simulator, and a mobile road dust measurement vehicle.
The results for gasoline, diesel, and electric vehicles were as follows. PM10 emissions were 42.3 mg/km for gasoline vehicles, 43.2 mg/km for diesel vehicles, and 47.7 mg/km for electric vehicles. PM2.5 emissions were 14.5 mg/km for gasoline vehicles, 14.1 mg/km for diesel vehicles, and 13.9 mg/km for electric vehicles.
In the case of the latest internal combustion engine vehicles, the current technological advancement of engine combustion and after-treatment devices have evolved considerably to reduce particulate matter emission. As a result, the share of non-exhaust PM in the total PM emissions has been increased to more than 90%.
According to Dr. Lee, “Electric vehicles do not emit toxic exhaust gases and greenhouse gases at all. Nevertheless, our results show that they do emit a significant amount of non-exhaust emissions.” He added, “To improve urban air quality, the government should parallelly implement various policies to mitigate non-exhaust emissions, rather than only focusing uptake of the electric vehicles.”
The current research is published in Science of The Total Environment.
More information:
Sang-Hee Woo et al, Comparison of total PM emissions emitted from electric and internal combustion engine vehicles: An experimental analysis, Science of The Total Environment (2022). DOI: 10.1016/j.scitotenv.2022.156961
Provided by
National Research Council of Science and Technology
Citation:
First integrated measurement of exhaust and non-exhaust particulate matter emissions of vehicles (2022, October 11)
