Energy–environment efficiency analysis of railway transport: is Europe moving towards sustainable mobility?

Greenhouse gas emissions, acidification, and the dispersion of particles are negative side effects of railways that have received notable attention in Europe but are seldom considered in performance evaluations. The objective of this work was to assess the efficiency of European railways involved in the commitment signed by the international railway association (UIC) and The community of European railway and infrastructure companies (CER), considering the action of 14 rail companies to reduce negative externalities. Data envelopment analysis was applied under the framework of a slacks-based measure and the technique for order of preference by similarity to ideal solution to account for undesirable outputs and ensure unique rankings. Three different measures were considered: two ordinary energy efficiency models, with and without environmental restrictions, which are input–output ratios, and the eco-efficiency, which is an economic performance-to-environmental impacts ratio. The first two models were found to be similar to each other but different to the eco-efficiency, as a high ordinary efficiency ranking generally is not equivalent to high eco-efficiency. The results indicate that the average performance of the firms is low, but with a considerable temporal growth which is driven by environmental factors. Several policy-making implications are addressed to assist railway efficiency improvements and avoid anomalies in environmental performance evaluations. This data envelopment analysis application is the first to incorporate several air pollutants in railway efficiency assessment. Graphical abstract Time-series evolution of the efficiency scores for railway companies involved in the UIC-CER commitment during 2011–2019.