Hydrogen Fuel Cell-Powered Rail Trains for Passenger Transport Applications on Non-Electrified Secondary Lines

The European Green Deal aims to reduce greenhouse gas emissions (GHG) to 90% by 2050, of which the transport sector currently contributes around 34%. Innovation in advanced vehicle powertrain technology and the massive use of energy from renewable sources are key factors in achieving these goals. Within this framework, the passenger rail transport system plays a strategic role. This paper discusses and evaluates the application fields and energy options of the hydrogen carrier in passenger rail transport on non-electrified railway lines where highly polluting diesel trains currently operate. In this specific case, the use of "green" hydrogen for vehicle traction seems to be one of the most promising and sustainable approaches, as the entire production and use cycle is GHG emissions-free. In this paper, a power train configuration without electrochemical batteries is proposed for the traction of rail vehicles. As a case study, a railway train powered by a hydrogen fuel cell hybridized with a flywheel energy storage system (FESS) running on an existing Italian non-electrified suburban line is simulated using a numerical model. Finally, the hydrogen consumption for traction requirements is carried out. The results show that, compared to a similar diesel train, a hydrogen train allows traction energy and emissions saving to be reached.