Chapter 9 - Energy Use and CO2 Production in the Urban Passenger Transport Systems of 84 International Cities: Findings and Policy Implications

Abstract

This chapter highlights some major differences in transport patterns in metropolitan areas in 11 different regions around the world and focuses attention on passenger transport energy use and CO2 emissions. US cities, followed a long way behind by Canadian and Australian cities, are the heaviest passenger transport energy users and CO2 producers from transport in the world, while Chinese cities are the lowest. The patterns demonstrate the energy and CO2 reduction potential of reducing the role of the automobile in urban transport systems and enhancing the role of public transport and non-motorized modes. Motorcycles are also relatively energy- and CO2-efficient modes, but they are associated with high local smog emissions, noise, and traffic danger, which can detract from their energy and greenhouse benefits. Urban passenger transport energy use and CO2 emissions can be linked directly and indirectly to a host of factors. Some significant factors found internationally include the extent and quality of the public transport system, especially the kilometers of dedicated public transport right-of-way and the amount of service provided by urban rail systems. Lower income cities provide comparatively high levels of public transport service, but little of it is rail. Freeways and high levels of parking in the CBD are associated with higher energy use and CO2 emissions in cities. Minimizing such infrastructure in cities will give energy and CO2 benefits. Passenger transport energy use and CO2 are of course dependent upon the modal share between private, public and non-motorized modes, but also upon the relative energy use of different modes.