Analysis of Hydrogen-Powered Propulsion System Alternatives for Diesel-Electric Multiple Unit Regional Trains

Regional railways, often characterized by non-electrified lines and transport services provided by diesel-electric multiple units, require the identification of alternative propulsion systems to meet strict emission regulations. Hydrogen, when produced using green electricity, offers a carbon-neutral operation of trains from a well-to-wheel perspective. With the aim to identify an optimal alternative to conventional diesel traction, this paper presents a comparative assessment of hydrogen-powered propulsion systems with the internal combustion engine or fuel cells as the prime mover, in combination with different energy storage technologies, including Lithium-ion batteries and double-layer capacitors. The analysis encompasses the identification, design, modelling and assessment of alternative powertrains, with respect to the particular case-related constraints imposed by the infrastructure, technical and operational requirements. Focusing on the regional railways in the Northern Netherlands, we investigate the possibilities in converting conventional benchmark vehicles operating on the network and provide a simulation-based assessment in terms of overall energy consumption. The results indicate the highest fuel savings from the propulsion system with fuel cells and hybrid energy storage system, with negligible mass limit excess.