The shiny blue hull of train manufacturer Stadler’s Berlin factory doesn’t look like a Guinness Book of Records case – more like a normal regional train that still lacks wheels and windows. After assembly, however, Stadler wants its new development to be inspected by record keepers: as the battery-powered hybrid train with the longest range yet. The “Flirt Akku” (light rail, intercity and regional) is supposed to travel up to 185 kilometers in pure battery operation at a speed of 80 km / h – and eventually replace diesel trains on European rails.
At Stadler, the decision was taken in 2015 to stop the production of pure diesel trains. The problem: One in four trains in Germany still run on fossil fuels, as only 60% of the rail network is electrified by overhead lines. And the expansion is slow. Instead of the 500 kilometers of new airlines targeted by the federal government per year, last year it was only 180, years before even less. The target of 70% electrified rail by 2025 agreed in the coalition agreement will almost certainly not be met.
In order to eliminate emissions from rail transport as quickly as possible, rail companies are therefore increasingly relying on more flexible alternatives such as battery-powered hybrid trains. They can work with overhead lines as well as with batteries. Not only Stadler, but also competition from Siemens, Alstom and Bombardier offer comparable models and have already sold them to local German transport associations. Steffen Obst, Sales Manager at Stadler Germany, explains: “We wanted to maximize the reach that can be achieved with the current state of the art.
Ten times the capacity of a typical electric car
To this end, we have cooperated with the Technical University of Berlin, among others, to find the most suitable battery technology for regional traffic. Obst says: “Most batteries today are produced for cars, so they are designed for a lifespan of seven to eight years and a maximum use of 100,000 kilometers per year. A train travels two to three times as much and that for at least 30 years. “The development team was able to achieve ten times the capacity of a typical electric car with four lithium-ion batteries at the top and bottom of the model. Flirt train established. Under test conditions the possible record range has been reached; in normal operation a minimum range of 80 kilometers should be created. A full charge under the contact wire should take 20 minutes, at the charge up to an hour.
Markus Hecht, professor and head of the rail vehicles department at TU Berlin and not involved in the Stadler project, believes that battery-powered hybrid trains are a crucial transition technology in transport’s transition to climate neutrality: “They use energy much more efficiently than hydrogen or diesel trains. They are quieter and – provided they are supplied with renewable energies – CO₂ neutral. “In addition, they would make optimal use of the existing infrastructure, because they can recharge their batteries while passing under the overhead lines. However, the objective must be to electrify the entire rail network as quickly as possible,” explains Hecht. This would not only be more energy efficient, but also more economical. In addition, locomotives with high traction power, for example those of long freight trains, could also run on electricity. today is not yet sufficient for this.
Stadler’s fruit sales manager agrees with Hecht on the last point. Nevertheless, he believes in the long-term market opportunities of his development: “There will always be sections where the construction of an overhead line will not be profitable. A wireless train with its flexibility is better suited for this. The production of the first Flirt batteries is now expected, from 2023 55 trains from Pankow are expected to make rail traffic in Schleswig-Holstein CO₂-free. Competitors Siemens and Alstom deliver their first trains to Baden-Württemberg and Saxony at around the same time.
The extent of the contribution of battery-powered hybrid trains to German climate targets will certainly also be a matter of time, says Markus Hecht. The process of purchasing a train takes between four and eight years, from planning to tendering and production to commissioning. And transport companies usually only deal with new acquisitions when old vehicles need to be scrapped. With diesel trains currently in service, this will only be the case on a large scale from 2032, the last ones would be regularly taken out of service in 2054. And even if all diesel trains were to be modernized, Professor Hecht warns: ” Climate neutrality on the railways will only help us to a limited extent as long as it only accounts for seven percent of total traffic in Germany. A lot has to happen politically in order to fully exploit the climate protection potential of the railways in the coming years.