Will battery or hydrogen trains be the future? The vision of Siemens Mobility
As a manufacturer of both hydrogen and a battery trains, of course Siemens Mobility sees both technologies as good alternatives to replace diesel operations in rail. To date, more battery trains have been sold by the German company than hydrogen trains, but there is a big future for hydrogen as well on non-electrified tracks longer than 100 kilometres, says Rolling Stock CEO Albrecht Neumann.
Currently, 9 hydrogen fuel cell trains have been ordered at Siemens Mobility for three projects in Germany, and 61 battery trains are under order for four projects, three in Germany and one in Denmark. Both the Mireo Plus B and the Mireo Plus H were presented during a media day at Siemens Mobility’s Test and Validation Centre in Wildenrath, North Rhine-Westphalia on April 26, which RailTech attended.
“We feel both technologies clearly complement each other. Batteries are for the shorter distances, and on sections of more than a hundred kilometres without overhead lines, I think there is no alternative to hydrogen”, says Albrecht Neumann, who has been CEO of the Siemens Rolling Stock division for four years.
He points out that in Western Europe, the non-electrified sections are not that long in most cases. “That is the reason why we currently have more demand for our battery trains. Still, there is quite a part of the network which is not electrified and will probably not be electrified in the next 10 years, so both technologies will be needed.”
Of all railway tracks in the EU, 45 per cent on average is not (yet) electrified. Of the main railway network, just over half, or 60 per cent is electrified, on which 80 per cent of traffic is running. Mainly smaller, regional lines remain (partly) without overhead lines, as this is high in costs and often not deemed viable for lower traffic lines.
Charging and refuelling
When it comes to hydrogen trains, a factor playing into how widely hydrogen propulsion may be adopted in rail, is the price. “I cannot answer what the price of hydrogen will be in two or five years. But we do expect the prices will go down”, says Neumann. He points to nearby wind turbines adjacent to the Siemens testing centre: “They are standing still and are currently not in operation, because the energy is not needed. In a short period of time, there will be a small hydrolyser next to the wind turbine, generating green hydrogen when the energy is not needed for the electrical grid. We could probably use it directly in our trains here.”
The concept of locally producing hydrogen for use in trains is also under development at Deutsche Bahn, which developed a mobile filling station as part of the H2GoesRail project, which was also showcased at the test site. Lennart Fink, Project Manager of the H2goesRail project at DB Energie, informed that coming September, the mobile filling station will be moved to Tübingen in Baden-Württemberg, where it will be connected with an electrolyser powered through the catenary system. After setting up the system, green hydrogen will be produced on site by December, is the plan.
Just as hydrogen trains need refuelling infrastructure, battery trains need charging infrastructure, either in the form of smaller sections of electrification, also called ‘overhead islands’, or stationary charging stations. The first overhead islands in Germany will be constructed by Deutsche Bahn in northern state Schleswig-Holstein, where battery trains of Swiss manufacturer Stadler have been ordered for operations.
Which train for which situation?
Regarding the choice for operators and transport authorities whether to opt for hydrogen or battery driven trains, the question of costs overall plays a minor role however, says Neumann. “I think nobody will use a hydrogen train for short distances. The battery train will always be the cheaper option, so wherever the battery train fits, that’s the better solution. But for longer distances, battery trains simply do not qualify because they cannot serve the purpose for those distances.”
Neumann points out that the range or deployment for battery trains is around a 100 kilometres on non-electrified sections.This is for tracks that are more or less on flat terrain. If railway lines go into the mountains, the mileage may be shorter. That is why Siemens offers them both. Elmar Zeiler, Head of Commuter and Regional Trains at Siemens Mobility, explains both the alternative drive trains are based on the standard Mireo electric multiple unit (EMU) for operation under the catenary. “Except for the different propulsion systems and different containers on top and under the train, it is more or less exactly the same train.” Indeed, on board both of the trains running, virtually no difference in feeling how the trains run can be noticed. As the hydrogen is converted into electricity in the fuel cells, both trains run on electrical traction motors.
For the observant passenger, occasionally a slight vapour can be seen emitted from the top of the hydrogen train, as the on-board conversion of hydrogen into electrical energy generates some water. Jochen Steinbauer, Platform Director H2 Technologies for Regional Trains at Siemens Mobility, says that Siemens started development of both battery and hydrogen around the same time, back in 2017. “But we knew very well that the hydrogen train is more complex and innovative, which is why it took some more time to develop.”
The first Siemens hydrogen train will enter passenger service in Baden-Württemberg Southern Germany in the beginning of next year. This will be on the Nagoldtal railway, in cooperation with Deutsche Bahn, as part of a research funded by the National Innovation Programme for hydrogen and fuel cells (NIP) funded by the German government. After a study of the state and research partners, battery trains were however found to be the logical choice, both on an operational and economic level.
The first battery train built by the company will enter passenger service earlier, in December of this year in the same state, on the Ortenau/Hermann-Hesse-Bahn. “A nice feature is that you could even combine the battery and the hydrogen train in operations”, says Albrecht Neumann. “For example, going the first 80 kilometres in double traction, and then splitting the train where the hydrogen train part serves a destination on a further distance, and the battery train a closer destination”. Though a possibility, this combination has not been ordered as of yet.
However, Siemens believes the market will further develop without a doubt. Elmar Zeiler: “Many customers are currently looking at both options, and are working to understand the technologies and what each advantages are for their specific network. Both have good reasons to be deployed. It depends on the distances, track grades, the availability of electricity or local hydrogen in the area, from our point of view, there is no right or wrong”.