Characterizing real unit emissions for light duty goods vehicles

Thirty-nine private light duty goods vehicles (LDGVs) were instrumented and monitored in actual conditions of use, over about 78,000 km and 9800 trips. This database allowed the building-up of specific driving cycles, representative of the driving, loading and operating conditions of each vehicle category. Then 27 diesel LDGVs were tested on a chassis dynamometer using these driving cycles. Each vehicle category was tested according to 6–9 hot cycles, differing by their kinematics and their loading rates. CO, HC, NOx, CO2 and particulate emissions together with fuel consumption were evaluated. Results show the influence of the average cycle speed, the load and the vehicle category on emissions. These measured emissions are quite different from passenger car emissions, and from emissions calculated using the European Meet/Copert III model.