Commercial vehicle emissions in urban areas

摘要

An experimental method has been set up to assess the pollutant emissions from 6 common comerical vehicles following typical driving patterns. The 6 vehicles, ranging from a 3.5-ton van to a 5-axle semi-trailer and an urban bus, met the EURO 1 limits. Emission rates f CO,CO2, HC, NOx and particulates (in g per km) are provided for 4 different travel or average speeds, 20, 40, 60 and 80 km/h, combined with 2 driving behaviours (with the exception of the bus). Measurements give a limited but precise picture of the emissions from this type of vehicle. Comparisons with data from other laboratories show a good cosistency in the average speed related trends. As for passenger cars, data for commercial vehicles shows that emissions are highly dependent upon average speed, and this is particularly true in the urban speed range (<50 km/h). Thus the lower the travel speed is, the higher the emissions are. Repetitions of stops, accelerations and decelerations, as encountered in urban traffic, are high magnifying factors to air pollution. MOre precise results highlight the improtance of traffic regulation and the design of intersection regarding environmental aspects.