Live Coverage: UITP's 'Battery Innovation Across Rail – From Safety to Technology' Webinar

RAILTARGET brings you updates from the UITP webinar 'Battery Innovation Across Rail – From Safety to Technology,' which will explore how batteries can be integrated into different rail vehicles, looking at current projects, propulsion technologies, operational use cases, maintenance, economics, and safety as the sector seeks more flexible ways to decarbonise rail.

9:00 Georgiana Tuta, Membership Development Manager at UITP, opens the webinar with a brief introduction to the association. UITP works globally across the public transport sector, bringing together authorities, operators, industry, academia, research organisations and other associations, with around half of its membership currently based in Europe.

She points out UITP’s three main areas of work: advocacy, knowledge and networking. On the policy side, the association works with decision-makers to position public transport at the centre of climate action and sustainable urban mobility. It also publishes reports, data and sector research, while its academy provides training for public transport professionals.

Tuta also points to UITP’s involvement in European and international projects, including rail-related initiatives, and its programme of conferences, workshops, webinars and regional events.

9:10 Bruce Warner, Mobility Segment Manager at Hitachi, briefly introduces Hitachi as a global technology company with around 300,000 employees, 618 group companies and annual revenue of about USD 65 billion. Within mobility, Hitachi is active across rolling stock, signalling, communications and other rail systems, while its energy activities also cover the infrastructure needed to support electrified transport.

Warner then says that around 75% of passenger rail activity already takes place on electric trains, while rail carries roughly 8% of global passenger traffic and 7% of freight but accounts for only 2% of total transport energy demand. With passenger and freight rail activity expected to more than double by 2050, he argues that batteries could help rail accommodate this growth while extending electrified operation beyond conventionally wired routes.

Looking at Europe, Warner says roughly 60% of the network is electrified, leaving a substantial share without continuous power supply. Many of these non-electrified sections are relatively short, which makes them particularly interesting for battery operation. Battery trains can avoid the cost of installing catenary through difficult locations such as tunnels and bridges, while eliminating local exhaust emissions and reducing some of the infrastructure and maintenance requirements associated with conventional electrification.

9:15 He says that there is no single way to supply power to a battery train. Charging infrastructure can be connected to different DC and AC railway systems, while the technical interface between the train and infrastructure can vary considerably. Warner points to the need for greater interoperability and standardisation, saying Hitachi is working with UITP and other industry stakeholders to bring manufacturers, infrastructure suppliers and operators together around common interfaces.

9:20 Warner says there are three possible charging strategies. The first is overnight charging at a depot, which requires relatively large onboard batteries and leaves the train dependent on a long charging period. A second option adds charging at terminal stations, reducing the amount of energy that needs to be carried onboard.

The third is flash charging at intermediate stops, where the train receives short bursts of energy while passengers board and alight. According to Warner, this can allow smaller and lighter batteries, avoid long charging downtime and make the approach particularly suitable for high-frequency services. It can also make it easier to integrate wayside energy storage where peak electricity demand has to be managed.

9:25 To show how this works in practice, Warner presents Hitachi's battery hybrid trial in the UK. Batteries were installed on an existing train and tested under real operating conditions. He says the trial achieved a range of around 60 km on battery power, with acceleration comparable to diesel operation.

Fuel savings reached between 35% and 57% depending on the driving mode, while charging at 500 amps allowed the batteries to recharge in around 15 minutes. Warner says the initial results are promising, arguing that battery trains could ultimately provide a cheaper and more reliable alternative on routes where full conventional electrification is difficult to justify.

9:30 Bogdan Vulturescu of SNCF is next to speak, focusing on how the French operator is using battery technology to decarbonise its existing regional fleet rather than relying only on new rolling stock.

He says SNCF operates around 2,300 regional trains, with about half still equipped with diesel engines, either as pure diesel or dual-mode units. While some of the oldest trains will eventually have to be replaced, a large part of the fleet is still relatively young. For these trains, SNCF is looking at refurbishment and conversion to battery-electric operation instead of early replacement.

The current programme includes the conversion of existing AGC regional trains into BEMUs, with several units being prepared for operation in different French regions. Vulturescu says SNCF spent a lot of time on the safety case, particularly around lithium batteries, before receiving authorisation at the beginning of 2026. Driver training followed, with the first train entering regular operation in southern France in July.

9:35 The converted AGC has an 80 km battery range at end of battery life, based on using only around 50% of the available depth of discharge. At the beginning of battery life, Vulturescu says the practical range is closer to 110 km, and an additional reserve is retained for operational disruptions or infrastructure problems.

Performance remains close to that of the original train. The BEMU can operate at 160 km/h, delivers around 1.8 MW under catenary and 1 MW on non-electrified sections, and now recovers energy during braking. A full battery charge takes around 25 minutes while running under catenary or when supplied with 25 kV AC at standstill, and around 60 minutes under 1.5 kV DC.

For drivers, SNCF has deliberately kept the changes limited. One of the key additions is a live display showing the equivalent distance that can still be covered with the remaining battery energy, helping drivers manage the train without fundamentally changing their working environment.

Vulturescu notes that a battery train cannot be considered only as rolling stock. "Battery train is a system," he says, meaning that infrastructure, charging opportunities, operating rules and daily diagrams have to be considered together.

While around 84% of individual trips include less than 80 km without catenary, only about 55% of complete daily AGC diagrams can currently be covered with the existing 80 km battery autonomy. The problem is whether there is enough time and power available to recharge it before the next one.

9:40 SNCF is studying two main improvements: faster charging under the French 1.5 kV DC network and greater onboard energy capacity. A key condition of the current experiment is that no infrastructure modifications should be required. Instead, the constraints have to be managed through the rolling stock itself and through changes to operations.

The refurbishment involves removing the existing diesel power packs and replacing them with battery packs, converters, choppers and modified train software. Vulturescu says that working with an existing train is a different engineering challenge from ordering a new vehicle because older electronic systems can impose limitations on what can be changed.

9:45 SNCF is now testing the converted trains on several types of routes. On one line in southern France, around half of the journey is electrified and the train then covers a 32 km non-electrified section on batteries. Another route includes a 21 km unelectrified section, while a third allows extensive charging under wires before the train enters a longer battery-powered part of the journey.

These different operating patterns are intended to show where the current BEMU configuration works and where additional charging or onboard energy will be needed.

Vulturescu also points to issues that need to be addressed before wider deployment. Infrastructure managers must confirm that the electrical network can supply the necessary charging power, while operators need clear procedures for battery incidents. SNCF has paid particular attention to fire safety, smoke toxicity and the need for 24-hour monitoring in certain situations, areas where Vulturescu says operators still need more information and assurances from manufacturers and suppliers.

Summing up, he says onboard energy storage is already changing how railways have to think about rolling stock. Battery trains require cooperation between vehicles, infrastructure, software, operating rules and people.

For drivers, the transition has so far been relatively straightforward. Vulturescu says there has been strong interest in operating the new trains and that drivers adapt quickly once properly trained. For refurbishment projects, however, his recommendation is: work with experienced specialists, because converting an existing train is fundamentally different from buying a new one.

9:50 Bo-Kyong Kim, Principal Researcher at the Korea Railroad Research Institute (KRRI), looks at hydrogen trains using fuel cell–battery hybrid propulsion, focusing on what KRRI has already tested in South Korea and where the technology could go next.

Kim says hydrogen rail is very much a multidisciplinary topic, because the train has to bring together hydrogen storage, fuel cells, batteries, converters, traction equipment and energy-management software in one system.

She then looks at how hydrogen rail has developed internationally. Over the past 15 years, projects have ranged from shunting locomotives and trams to regional passenger trains, with examples in the United States, Japan, Spain, China and Germany.

Hydrogen becomes more interesting as trains get heavier and routes get longer. Batteries alone can work well for many shorter applications, but the amount of battery capacity needed for long-distance heavy rail quickly adds weight. In a hybrid setup, the fuel cell can provide the steady energy needed for range, while the battery deals with the parts of railway operation where power demand changes quickly.

9:55 Kim explains that the fuel cell and battery have different jobs onboard the train. The fuel cell works as the main energy source and performs best when its output remains relatively stable. The battery covers acceleration peaks and takes in energy recovered during regenerative braking.

An energy-management system sits between the two and decides where the power should come from at any given moment, which is important because a railway vehicle is constantly moving between acceleration, cruising and braking, while a fuel cell is less suited to rapid load changes. The battery helps keep the fuel cell operating under more favourable conditions and reduces stress on the propulsion system.

Kim then shows KRRI’s hydrogen train configuration. Instead of relying on a pantograph and continuous catenary, the vehicle carries hydrogen tanks, a fuel-cell system, DC/DC converters and a propulsion battery onboard. From there, much of the traction system works in a similar way to that of a conventional electric train.

10:00 Between 2018 and 2022, KRRI worked on a 1.2 MW, two-car hydrogen-powered train, including the propulsion system, integration, testing and the construction of hydrogen refuelling facilities. Because there was no established technical framework for this type of train in Korea, part of the project also involved developing technical specifications and safety requirements that could later support demonstration and commercial operation.

Kim says one of the main advantages being explored is the ability to run without continuous railway electrification. That could make hydrogen interesting for routes where installing catenary would be particularly expensive or impractical, while also providing an alternative to diesel. KRRI is looking at hydrogen as a possible technology for long-distance operation where continuous power infrastructure cannot be guaranteed, including potential future rail connections beyond South Korea.

For the prototype, researchers first simulated the route and traction demand to decide how the work should be divided between the fuel cell and battery. The fuel cell was intended to cover the more stable power demand, while the battery stepped in during peaks.

Kim says KRRI used conservative operating limits to reduce stress on the cells and extend their life, while regenerative braking energy is recovered back into the battery whenever possible. The train uses 700-bar hydrogen storage, and KRRI built dedicated refuelling infrastructure so the whole system could be tested in a realistic railway environment.

The point of those trials, Kim says, was to understand how the complete propulsion system behaves in real operation, where the weaknesses are and what still has to improve before commercial use.

10:10 The 1.2 MW programme is now moving towards demonstration and commercialisation, while work is also progressing on a 3 MW hydrogen-electric locomotive. Further ahead, KRRI is targeting a dual-mode hydrogen intercity train capable of around 180 km/h. The most ambitious part of the roadmap goes much further, with research into hydrogen high-speed rail at around 350 km/h stretching towards 2040.

Kim says that the next steps will depend on improving energy density, reliability, safety, system control and maintenance costs, while making sure that larger hydrogen systems can still fit into a railway vehicle without compromising its performance. For KRRI, the current prototypes are effectively the foundation for that work. The institute is using them to build up the standards, testing experience and operational knowledge needed for future hydrogen trains, with batteries remaining a central part of the propulsion concept.

This concludes the 'Battery Innovation Across Rail – From Safety to Technology'. Thank you for tuning in with RAILTARGET for the updates.