The environmental performance of different modes of transport – whether perceived or real – plays a major role in transport policy decision making. For example, priorities in infrastructure investments and pricing strategies are partly driven by (perceptions of) environmentally ‘good’ and ‘bad’ modes, with cars and aircraft generally figuring as ‘bad’ and rail and water transport as ‘good’. Indeed, if we calculate current average emissions of these four modes, such conclusions are easily drawn. It can be queried, however, whether this observation still holds upon closer examination. In practice, mopeds do not compete with aircraft. More generally, environmental comparisons between transport modes only make sense for well-defined, homogeneous and competing markets and for complete transport chains. If sound transport policy conclusions are to be drawn, moreover, analysis must move beyond the present to include the anticipated future environmental performance of the various modes of interest. Besides presenting a state-of-the-art review of the environmental performance of the main competing transport modes, this report has the additional aim of clarifying how the figures found in this study can be used in everyday transport (policy) decision making. This goal was added because experience has shown that environmental performance figures are all too easily put to generalised use. (Author/publisher)
Samenvatting