Are railways 'climate friendly?'

Rail is usually considered a 'green' mode of passenger transport, at least 'greener' than the car and aeroplane in terms of its relative impact on climate change. It is therefore only natural that rail will play an increasing role in meeting demand for transport when the aim is to reduce environmental pollution associated with transport operation. Yet referring to rail as 'green' has many limitations and can be misleading. In this context, the paper aims to examine the environmental impact from rail transport and to show how the above generalization depends on many different factors. Attention is focussed on comparing different trains (e. g. diesel versus electric, and in the latter examining how environmental impacts depend on the sources used to generate the electricity) and different modes (train versus car or plane). The scope for improving the environmental performance of rail through technical and operational measures is examined. How and where rail can play a role in achieving a more sustainable transport system is identified.