Swiss train manufacturer Stadler and Sardinian transport operator ARST are officially planning the development of the world’s first hydrogen-powered train built specifically for narrow-gauge lines.
Notably, the introduction of 10 hydrogen trains in Sardinia will cut more than 2,100 tonnes of CO2 per year compared to diesel trains (equivalent to roughly 450 car trips around the globe).
The trains are scheduled to enter passenger service in 2028, specifically serving the ARST-operated lines: Alghero airport-Mamuntanas, Sassari-Alghero, and Sassari-Sorso.
“With the commissioning of the first hydrogen-powered train designed for narrow-gauge railways, Sardinia is proving itself a pioneer of technological innovation in the transport sector. This is the first train of its kind, specifically designed for contexts similar to ours with the aim of turning a limitation into a great opportunity, said Barbara Manca, regional transport minister of the Autonomous Region of Sardinia.
“The hydrogen trains, which will be deployed on ARST lines, are a shining example for the environment, the local economy and the development of key skills in our region,” added Manca.
Reducing carbon emissions
Italy’s regional narrow-gauge railways have long used diesel power due to a geographic trap: their tight curves and strict weight limits have made modern, heavy electric trains impractical. However, that era is ending now with the arrival of specialised, lightweight hydrogen technology designed to navigate these restrictive, scenic tracks without fossil fuels.
These trains feature a unique propulsion system that houses hydrogen tanks and fuel cells inside a central 'Power Pack' carriage, which acts as a rolling charger to power the train’s electric traction batteries on non-electrified lines.
The hydrogen fuelling these trains will be manufactured locally using 100% solar power. This creates a completely closed-loop clean energy system. The train network will emit nothing but water vapour.
“Stadler is the only train manufacturer in the world that designs and builds hydrogen trains for narrow-gauge lines. Together with ARST, we have developed a solution that makes a tangible contribution to the decarbonisation of rail transport,” noted Dr Ansgar Brockmeyer, head of marketing and sales and deputy CEO of the Stadler Group.
Passengers will notice an immediate difference. The new models remove the heavy vibrations and loud rumble characteristic of old regional diesel engines. It will feature low-floor boarding for accessibility and massive panoramic windows designed to show off the Italian countryside.
Moreover, passengers benefit from bright, air-conditioned cabins, while crew members receive dedicated amenities like private entrances and independent climate control.
Total 10 trains proposed
Under a 2023 agreement, Stadler will supply 10 hydrogen vehicles to Sardinia’s ARST as part of an Italian government initiative to decarbonise narrow-gauge regional rail networks.
While Sardinia is premiering the technology, the rest of southern Italy is waiting in line.
Stadler is already building nine identical units for Ferrovie della Calabria. The firm is also constructing two units for Sicily’s Ferrovia Circumetnea. The Sicilian models are being calibrated with specialised traction systems to climb the steep volcanic slopes surrounding Mount Etna.
Prior to carrying passengers, the new hydrogen trains would need to pass a series of safety and operational tests. These evaluations ensure full compliance with the strict national guidelines regulated by the National Agency for the Safety of Railways and Road and Motorway Infrastructure, Italy’s transportation safety agency.
All of these upcoming fleets are currently being manufactured at Stadler’s headquarters in Bussnang, Switzerland, signalling a broad, quiet revolution for Europe’s forgotten tracks.