Assessment of Real World On-Road Vehicle Emissions under Dynamic Urban Traffic Conditions in Delhi

Abstract. A mobile laboratory was used to measure on-road vehicle emission ratios during the MCMA-2003 field campaign held during the spring of 2003 in the Mexico City Metropolitan Area (MCMA). The measured emission ratios represent a sample of emissions of in-use vehicles under real world driving conditions for the MCMA. From the relative amounts of NOx and selected VOC's sampled, the results indicate that the technique is capable of differentiating among vehicle categories and fuel type in real world driving conditions. Emission ratios for NOx, NOy, NH3, H2CO, CH3CHO, and other selected volatile organic compounds (VOCs) are presented for chase sampled vehicles and fleet averaged emissions. Results indicate that colectivos, particularly CNG-powered colectivos, are potentially significant contributors of NOx and aldehydes in the MCMA. Similarly, ratios of selected VOCs and NOy showed a strong dependence on traffic mode. These results are compared with the vehicle emissions inventory for the MCMA, other vehicle emissions measurements in the MCMA, and measurements of on-road emissions in US cities. Our estimates for motor vehicle emissions of benzene, toluene, formaldehyde, and acetaldehyde in the MCMA indicate these species are present in concentrations higher than previously reported. The high motor vehicle aldehyde emissions may have an impact on the photochemistry of urban areas.

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Differences in Energy Consumption in Electric Vehicles: An Exploratory Real-World Study in Beijing

Journal of Advanced Transportation ◽

10.1155/2017/4695975 ◽

2017 ◽

Vol 2017 ◽

pp. 1-17 ◽

Cited By ~ 11

Author(s):

Kezhen Hu ◽

Jianping Wu ◽

Tim Schwanen

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Electric Vehicles ◽

Real World ◽

Time Series Data ◽

Urban Traffic ◽

Environmental Benefits ◽

Series Data ◽

Traffic Conditions ◽

Infrastructure Design

Electric vehicles (EVs) are widely regarded as a promising solution to reduce air pollution in cities and key to a low carbon mobility future. However, their environmental benefits depend on the temporal and spatial context of actual usage (journey energy efficiency) and the rolling out of EVs is complicated by issues such as limited range. This paper explores how the energy efficiency of EVs is affected and shaped by driving behavior, personal driving styles, traffic conditions, and infrastructure design in the real world. Tests have been conducted with a Nissan LEAF under a typical driving cycle on the Beijing road network in order to improve understanding of variations in energy efficiency among drivers under different urban traffic conditions. Energy consumption and operation parameters were recorded in both peak and off-peak hours for a total of 13 drivers. The analysis reported in this paper shows that there are clear patterns in energy consumption along a route that are in part related to differences in infrastructure design, traffic conditions, and personal driving styles. The proposed method for analyzing time series data about energy consumption along routes can be used for research with larger fleets of EVs in the future.

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