Drivers and Limits

Continued growth of car transport, rapid expansion of air travel, and increased freight transport makes transport the fastest growing source of greenhouse gas emissions worldwide. Advances in transport technologies leading to improved energy efficiency and reduced carbon intensity of fuels have been offset by steady increases in e.g.: demand of heavier vehicles, demand for leisure trips, longer commuting, and a growing role of high speed modes. This trend sets a distinct contrast with the greenhouse gas reduction target. Few dispute that solutions must be found to this problem, but there are significant uncertainties about if and how to intervene in transport demand growth in time, without damaging the economy. The aim of this project is to gain a deeper understanding into the drivers and limits of structural transport demand that can help determine how to reduce transport growth – and thereby climate and congestion effects - with minimal negative effect on the economy.



We focus on four important themes in the description of the transport drivers: long distance trips; demography and socioeconomic; urban structure and infrastructure; and freight. Despite being four of the main challenges in transport growth, knowledge about their relative importance and the influence is not very well understood. The themes will be explored using both qualitative and quantitative methods. The theoretical foundations of the project comprise economic theory, spatial and environmental planning and social psychology. The empirical analyses will be based on existing transport databases combined with qualitative interviews and surveys. The outcome of the analyses serves as the basis for considering whether limiting trends can be expected in transport and how these may evolve over time. We formulate alternative visions and develop a scenario back casting process where alternative policies will be examined.