Stadler and Sardinian rail operator Azienda Regionale Sarda Trasporti (ARST) are preparing a hydrogen-powered train built specifically for Italy’s narrow-gauge railways. Testing began in Switzerland in October 2026, ahead of the planned launch of passenger services in Sardinia from 2028. The first vehicle is on trial along a purpose-prepared test line, approximately four kilometers long, between Hemishofen and Ramsen in the canton of Schaffhausen.
Italy’s regional railways include 950-millimeter-gauge tracks, particularly in Sardinia; the same constraints apply in Calabria and Sicily. Restricted dimensions and infrastructure limits make heavier conventional hydrogen multiple units difficult to deploy. Stadler’s train was designed for those conditions, not adapted from a standard-gauge model. Trials in Switzerland will assess performance and reliability before delivery and final testing in Italy. ARST said the trains would arrive in Sardinia having completed a major phase of testing, allowing the operator to move swiftly to final trials on its network.
Engineering for Narrow-Gauge Challenges
The train’s design centers on a Power Pack car that houses the hydrogen fuel cells and storage tanks, along with cooling systems. Electricity generated from hydrogen powers and recharges the traction batteries, which lead the train. Keeping the vehicle within the limits of narrow-gauge infrastructure is basic to the design, particularly on the narrow and often winding tracks served by regional railways in southern Italy.
The passenger cabin has air conditioning and panoramic windows. Step-free access accommodates people with reduced mobility, while dedicated spaces are provided for bicycles and wheelchairs. Passengers also get Wi-Fi and USB ports, alongside 220-volt outlets at every seat.
Routes and Rollout
ARST’s agreement with Stadler covers ten hydrogen trains. The first units are planned for the Alghero Airport-Mamuntanas and Sassari-Alghero routes, with Sassari-Sorso also on the list. The Sardinian trains are expected to begin passenger service from 2028, after testing and commissioning in Italy and the required safety procedures, including those overseen by the National Agency for Railway and Road Infrastructure Safety (ANSFISA).
Stadler estimates that replacing diesel trains with the ten-unit Sardinian hydrogen fleet will avoid more than 2,100 tonnes of carbon dioxide each year. The company compares that reduction with roughly 450 car trips around the globe. The environmental benefit depends on replacing diesel operation and using low-carbon hydrogen. Stadler’s stated plan is to produce the hydrogen using solar energy.
Expanding the Decarbonization Effort
The initiative extends beyond Sardinia. Stadler’s wider Italian program includes nine hydrogen trains for Ferrovie della Calabria, plus two for Ferrovia Circumetnea in Sicily, alongside the ten for ARST, for a planned total of 21 vehicles. The Schaffhausen test line is intended to support testing and commissioning for the fleets over a three-year program. Stadler is building the trains at its Bussnang facility in Switzerland as part of efforts to decarbonize regional rail services on lines where electrification is difficult or impractical.
Italy’s push for cleaner railways reflects a wider European shift toward lower-emission transport. New technologies are reshaping the continent’s rail field, and projects like this echo the ambition of Switzerland’s vast underground freight network, which is also redefining how Europe moves goods and people. For a closer look at how Swiss engineering is influencing European rail, see this overview of Switzerland’s underground tunnel system.
