Development of Driving Cycle for Passenger Cars and Estimation of Vehicular Exhaust Emission Factors

Abstract

Driving pattern of the given vehicle in a city is represented by the driving cycle which is used by modal models for estimation of vehicular emissions. In this study, a driving cycle was developed for passenger cars in the city of Islamabad. A representative route for city was identified which included parts of highway, arteries, and streets. Speed-time data was collected along the selected route in both peak and off-peak hours. The on-board measurement method was adopted for data collection on highways, whereas on arteritis and streets, chase car method has opted for data collection. The developed cycle showed comparable values of average speed and acceleration with New European Driving Cycle (NEDC), but acceleration and deceleration were observed to be lower. The emission estimation and fuel consumption were calculated by the Comprehensive Modal Emission Model (CMEM) for 4 selected vehicle types. The average emissions for the selected vehicles were 204.4 g CO2 /km, 2.3 g CO /km, 0.09 g HCs /km, 0.31 g NOx /km emitted, and 65.7 g of fuel consumed /km. The developed cycle showed higher fuel consumption and CO2 emissions /km traveled than NEDC for all 4 passenger car types. However, HCs, CO, and NOx emissions were lower. The developed driving cycle can be used for estimation of the emissions from passenger cars in the city and this information can be useful for future emission projections and policy making.