Sardinia, the first hydrogen train designed for narrow-gauge railways makes its debut
Stadler and ARST (Azienda Regionale Sarda Trasporti) have presented in Switzerland, at the Erlen testing center, what is defined as the world's first hydrogen train developed specifically for narrow-gauge railways. This project was created to meet the specific needs of Sardinia's railway network, where starting in 2028 the new trains will enter service on the Alghero Airport-Mamuntanas, Sassari-Alghero, and Sassari-Sorso lines.
The distinctive feature of the project lies not only in the fuel cell technology, already adopted on some European networks, but also in the necessity to design an entirely new vehicle. The Italian narrow-gauge lines, with a track width of 950 mm inherited from infrastructure built in the 19th century, impose strict load limits on the axles that prevent the adaptation of traditional hydrogen trains designed for standard 1,435 mm lines.
To comply with these constraints, Stadler has developed a lightweight structure with an aluminum body and a specific profile for this type of infrastructure. The entire propulsion system is concentrated in a central carriage called the Power Pack, which houses hydrogen tanks, fuel cells, and energy conversion systems. The electricity produced powers the traction batteries, which in turn provide energy to the electric motors of the train.
This solution allows for passenger carriages fully dedicated to traveler comfort, with a lowered floor to facilitate access for people with reduced mobility, air conditioning, large panoramic glass surfaces, and a reduction in both noise and vibrations compared to current diesel trains. There are also dedicated spaces for onboard staff with independent access and separate air conditioning.
One of the most innovative aspects of the initiative concerns the fuel production. Unlike other European hydrogen-based rail projects, where refueling occurs via external infrastructures without guarantees on the origin of the hydrogen used, ARST will independently produce the fuel through an electrolysis plant powered exclusively by photovoltaic energy. The goal is to create a completely zero-emission supply chain, from energy production to rail traction.
According to estimates provided by the involved companies, the ten trains ordered by ARST under the framework agreement signed in 2023 will avoid over 2,100 tons of CO₂ emissions annually compared to current diesel trains, a value that Stadler compares to about 450 car journeys around the globe. The project is part of a broader program promoted by the Italian Government and the Ministry of Infrastructure and Transport to support the decarbonization of non-electrified regional railway networks in the South.
In addition to Sardinia, Calabria and Sicily will also adopt the technology developed by the Swiss company: nine trains destined for Ferrovie della Calabria and two others for Ferrovia Circumetnea are currently under construction. Before the start of commercial service, scheduled for 2028, all trains must complete the certification process according to the procedures of the National Agency for Railway Safety and Road and Highway Infrastructures (ANSFISA).