The final report of the German hydrogen‑tram project, dated 15 October 2023, presents a comprehensive assessment of the vehicle’s technical performance and design evolution. The study was carried out through a series of work packages that integrated simulation, component design, risk analysis, and full‑scale CAD modelling. The simulation model was used to evaluate the temporal correlation between electrical and thermal energy demand under a range of operating scenarios, climatic conditions, and energy‑storage control strategies. The analysis identified coverage gaps and enabled the derivation of optimal control strategies. The results show that the hydrogen‑driven tram behaves similarly to a conventional overhead‑line tram, but the inclusion of an energy‑storage system allows more efficient handling of topologically demanding routes, as braking energy can be recovered rather than dissipated through braking resistors. The vehicle’s behaviour under different loading conditions and driving styles remains consistent with expectations for an overhead‑line tram, although the higher vehicle mass introduces minor variations. The fuel‑cell operating state was identified as an area for further optimisation, with potential savings to be realised while maintaining life‑cycle and control‑complexity considerations.
In the vehicle‑design phase, component integration of the fuel‑cell system was continuously updated in the 3‑D model. Weight, axle‑load distribution, and centre‑of‑gravity changes were monitored throughout the design process, as these factors critically influence vehicle dynamics and safety. The design team performed a systematic weight‑management exercise, applying EN 15380‑2 for component mass accounting and EM 15663 and VDV 152 for loading conditions. Axle loads were derived from joint forces and wheel‑set load deviations, ensuring compliance with regulatory standards. The shift in the centre of gravity, particularly in the vertical direction, was quantified and its impact on dynamic behaviour and derailment safety assessed. Conservative assumptions were adopted, and further measures to lower the centre of gravity were recommended for operational deployment.
The CAD model of the complete vehicle was developed in detail. The wagon body, constructed as a steel‑welded structure, provides the primary structural stability and is essential for crash behaviour and repairability. Alternative materials and joining methods were evaluated but found unsuitable for the passenger‑transport context. Reinforcements were added to the roof structure to accommodate the heavy fuel‑cell equipment, with four portal‑like structures per end‑car illustrated in the model. Interior and exterior layouts were designed to meet passenger comfort, ergonomic, and brand‑recognition requirements while keeping procurement and spare‑part costs low and part commonality high. The driver’s area, interior trim, and exterior panels were all modelled to ensure a cohesive aesthetic and functional design.
A dedicated risk analysis was performed for the novel hydrogen components, identifying specific crash‑safety constraints that differ from conventional trams. The findings were incorporated into the overall vehicle model. A packaging study determined suitable installation locations for the battery‑fuel‑cell system components, ensuring optimal space utilisation and maintenance accessibility.
The project was executed by a consortium of industry and research partners, with the final report compiled by the project team and submitted to the funding authority on 15 October 2023. While the report does not list individual partner organisations or the funding body, it reflects a coordinated effort across multiple work packages to deliver a hydrogen‑powered tram that meets performance, safety, and operational criteria. The technical outcomes demonstrate that hydrogen propulsion, combined with energy‑storage management, can provide a viable alternative to conventional tram systems, offering comparable performance with potential for improved energy utilisation and reduced operational costs.