Real-world assessment of the energy consumption and emissions performance of a novel diesel-electric dual-drive locomotive

• Real driving emissions performance of a novel diesel-electric dual-drive locomotive was studied. • Operating conditions were very different between real-world and type-approval conditions. • 37 % of particulate matter emissions were released during stops. • Reducing excessive acceleration at high speed could greatly reduce CO and HC emissions. The huge demands for better energy efficiency and cleaner air from the public have driven governments to implement increasingly stricter emission standards. However, their implementation was not conducted uniformly among transport sectors. While road vehicles are now tested both in laboratory and real-world, rail vehicles are still only required to be tested in stationary conditions that have been shown to poorly reflect their real operation conditions. Therefore, this study aimed to assess the performance of a novel diesel-electric dual-drive locomotive in real-driving conditions. Significant variations were found for the tested locomotive in terms of both the share of idling time and the share of time the engine operated beyond the type-approval tests. The tested locomotive spent a similar share of time idling (24 %) as at its intended speed (60–90 km/h). It was found that 37 % of the particulate matter emissions were released during stops. Reducing the amount of time when the vehicle was accelerating at more than 0.5 m/s 2 , especially at speeds over 60 km/h, could reduce 50 % carbon monoxide emissions and 40 % hydrocarbon emissions. The findings suggest that incorporating the practice of eco-driving should be considered to significantly reduce the pollutant emissions from the railway sector.