The new train, known as the SRHe 113, has been developed for Sardinia’s 950 mm narrow-gauge network and was officially presented at Stadler’s facility in Erlen, Switzerland. It is expected to enter passenger service from 2028 as part of a broader programme to modernise regional rail operations on the Italian island.

The launch is notable not only because it introduces hydrogen propulsion to a highly specialised part of the rail market, but also because it pushes decarbonisation beyond standard-gauge mainline networks into smaller regional systems that have historically had fewer technology options.

First hydrogen train built for 950 mm narrow-gauge lines

The SRHe 113 has been designed specifically for Sardinia’s narrow-gauge routes, which use a track width of 950 mm rather than the standard gauge used on most European railways. That alone makes the project unusual, because much of the hydrogen train development seen in recent years has focused on standard-gauge regional services in Germany, France and elsewhere.

By contrast, this project targets a far more niche rail environment – one where operators still need modern, low-emission rolling stock but cannot simply adopt trains built for larger networks. Stadler’s answer is a low-floor hydrogen multiple unit tailored to the infrastructure and operating requirements of Sardinia’s secondary rail lines.

Two-car train with hydrogen booster section

The new train consists of two end cars linked by a central booster section that houses the hydrogen equipment while maintaining a full walkthrough connection for passengers.

It will offer 89 seats and a maximum operating speed of 100 km/h, making it suitable for regional and interurban narrow-gauge services rather than urban tram-style operations. The low-floor design is also significant, as it improves accessibility and aligns the train with modern passenger expectations for regional mobility.

In practical terms, the configuration is designed to balance the space needed for hydrogen propulsion with the need to preserve passenger comfort, accessibility and operational flexibility on relatively lightly built narrow-gauge infrastructure.

Passenger service planned in Sardinia from 2028

ARST plans to use 10 of the hydrogen trains on its narrow-gauge lines in Sardinia, with passenger services expected to begin in 2028.

The project stems from a framework agreement signed between ARST and Stadler in 2023 covering the development and supply of up to 10 hydrogen trains, including an initial firm order for six units. A further four trains were added later, bringing the Sardinian fleet plan to the full 10 units now expected to enter service.

For Sardinia, the programme represents one of the most important modernisation efforts on its secondary rail network in years, and one that could position the island as an early adopter of hydrogen rail technology in southern Europe.

Part of a wider Italian hydrogen rail push

The Sardinia project is not an isolated order. Stadler is also working on narrow-gauge hydrogen train contracts for other Italian regions, including Sicily and Calabria, where local operators are also preparing to introduce hydrogen-powered regional services.

That makes Italy one of the more active testing grounds for hydrogen rail in the narrow-gauge segment. Instead of limiting decarbonisation to flagship mainline routes, regional operators are exploring whether hydrogen can provide a practical alternative to diesel on smaller, non-electrified lines where full electrification may be difficult or too expensive.

Calabria had previously aimed to launch passenger hydrogen train services in 2026, highlighting how quickly several Italian regional networks are moving to explore this technology.

Why the train matters beyond Sardinia

The significance of the SRHe 113 goes beyond the island it was designed for. Narrow-gauge railways exist across parts of Europe and in many cases still depend on ageing diesel fleets because electrification is limited and off-the-shelf alternatives are scarce.

If Stadler’s hydrogen platform proves reliable in Sardinia, it could become a reference model for other non-standard regional networks looking to cut emissions without completely rebuilding their infrastructure.

That is particularly relevant for railways where line speeds are moderate, route lengths are manageable and electrification economics remain difficult. Hydrogen trains are not a universal solution, but in these types of networks they may offer a more realistic path to lower-emission operations than waiting for full infrastructure upgrades.

Hydrogen rail is moving into more specialised markets

Until recently, most public attention around hydrogen trains focused on standard regional services in northern Europe. What Stadler and ARST are doing in Sardinia suggests the market is beginning to move into a second phase – one where hydrogen is no longer being tested only on mainstream routes, but adapted to more specialised operating environments.

That shift matters because it broadens the potential role of hydrogen in rail decarbonisation. It is one thing to run a hydrogen train on a standard regional corridor. It is another to redesign the concept for a low-floor, narrow-gauge vehicle with different loading gauges, performance requirements and infrastructure constraints.

The SRHe 113 is therefore not just another hydrogen train launch. It is a sign that the technology is being pushed into more complex and less conventional parts of the rail sector – and that operators such as ARST are willing to use those smaller networks as laboratories for the next generation of clean regional transport