This paper aims at assessing the environmental contribution of high speed rail (HSR) focusing on the GHG emission and energy consumption balance and, ultimately, evaluating the conditions under which HSR investments can be considered the right track to sustainable mobility. For this purpose, we apply the transport hierarchy approach as a general framework for the assessment of HSR from a sustainable perspective. This framework establishes a priority order for the design and management of transport systems, differentiating four levels of priority: (1) demand minimisation; (2) modal shift and intermodality; (3) efficiency optimisation; and (4) capacity increase; thus new HSR projects falling directly into the last option. Taking into account the magnitude of the environmental problem as well as the commitments already signed by the EU, the most important contribution of HSR to sustainable mobility lies in its potential for environmental impact reductions, especially in regards to GHG emission and energy consumption. In an illustrative example of the project of Basque Y in Spain, we show that net GHG emission and energy consumption reductions are likely to be virtually null during the useful lifetime of the infrastructure. This example demonstrates the need to assess the environmental performance of HSR in a case per case basis.

This media entry was a contribution to the special session „Is High Speed Rail a sustainable mobility option?“ at the 5th International Degrowth Conference in Budapest in 2016.