A framework for estimating traffic emissions: The development of Passenger Car Emission Unit. (May 2016)

• Record Type: Journal Article
• Authors: Cen, Xuekai; Lo, Hong K.; Li, Lu
• Is Part Of: Transportation research. Volume 44(2016)
• Page Start: 78
• Page End: 92
• Publication Date: 2016-05
• Subjects: Emissions -- External costs -- PCEU framework -- Standard cost curve; Transportation -- Research -- Periodicals; Transportation -- Environmental aspects -- Periodicals; 354.76
• DOI: 10.1016/j.trd.2016.02.013
• Languages: English
• ISSNs: 1361-9209

Abstract

Highlights: A Passenger Car Emission Unit framework for estimating traffic emissions is developed. Massive emission factors are embedded into a standard curve and PCEU factors. Emission estimation now only requires speeds and traffic volumes by vehicle types. Abstract: In this study, we develop a Passenger Car Emission Unit (PCEU) framework for estimating traffic emissions. The idea is analogous to the use of Passenger Car Unit (PCU) for modeling the congestion effect of different vehicle types. In this approach, we integrate emission modeling and cost evaluation. Different emissions, typically speed-dependent, are integrated as an overall cost via their corresponding external costs. We then develop a normalization procedure to obtain a general trend that is applicable for all vehicle types, which is used to derive a standard cost curve. Different vehicle types with different emission standards are then mapped to this standard cost curve through their corresponding PCEUs that are to be calibrated. Once the standard cost curve and PCEUs have been calibrated, to estimate the overall cost of emission for a particular vehicle, we only need to multiply the corresponding PCEU of that vehicle type to the standard cost curve. We apply this PCEU approach to Hong Kong and obtain promising results. Compared with the results obtained by the full-blown emission model COPERT, the approach achieves high accuracy but obviates tedious inputs typically required for emission estimation.