Vehicle emissions and driving cycles: comparison of the Athens driving cycle (ADC) with ECE-15 and European driving cycle (EDC)

Abstract

Vehicle emissions constitute the main source of atmospheric pollution in modern cities. The
 increasing number of passenger cars, especially during the last decade, resulted in composite
 traffic problems with serious consequences on emissions and fuel consumption. This project
 was carried out in the Laboratory of Fuel Technology and Lubricants at NTUA in order to
 examine the effects of the driving patterns on fuel consumption and exhaust emissions from
 cars in the Athens basin.
 The typical driving profile consists of a complicated series of accelerations, decelerations and
 frequent stops and it is simulated by driving cycles on a laboratory chassis dynamometer. The
 New European Driving Cycle (NEDC) is applied in laboratory test approvals in the EU and is
 based on traffic data from European capitals (Paris and Rome). Traffic data from Athens was
 not included in the development of NEDC. The FTP 75 driving cycle and the Japan 10-15
 modal cycle are currently used in the United States and Japan respectively. The different than
 other European cities and rapidly changing traffic conditions in Athens as well as the
 expanding transportation network and the atmospheric pollution problems impose the need to
 develop the Athens Driving Cycle (ADC).
 In this paper, onboard electronic equipment (GPS, OBD II reader, accelerometer, etc) was
 used and “real world” traffic data was collected, covering almost all the Athens road network
 for a two year period. Dedicated software was developed for the statistical analysis of the
 recorded parameters and therefore the first ADC was modeled with the following
 characteristics: ADC duration is 1160 seconds, the overall distance is 6512 meters, the mean
 velocity is 20.21 km h-1 and the maximum velocity is 70.86 km h-1.
 For comparison purposes, three passenger cars of different classification (Citroen Xsara 1.6L,
 a Mitsubishi Space Runner 2.0L Turbo and a Chrysler PT Cruiser 2.4L Turbo) were tested on
 a laboratory chassis dynamometer, applying three distinctive Driving Cycles: the Urban
 Driving Cycle (ECE-15), the New European Driving Cycle (NEDC) and the newly designed
 Athens Driving Cycle (ADC). Results show that NOX emissions are higher in ADC than ECE
 and EDC, up to 2.5 times. Higher CO emissions are recorded during ADC for 1.6L and 2.0L
 cars while ECE-15 gave the higher CO emissions for the 2.4L vehicle. Overall HC emissions
 do not show any significant variation. Fuel consumption is higher for ADC mode in all cases.