Working alongside several industry partners, Baden-Württemberg studied what the possible alternatives for diesel-powered vehicles were. The authority no longer plans to purchase any diesel-powered trains, so needs to find emission-free solutions for its 16 non-electrified routes.
Transport minister Winfried Hermann said, “In order for the country to achieve its climate targets in the transport sector, diesel drives must be a thing of the past on the rails as soon as possible. Since the construction of overhead lines takes a long time and is sometimes very expensive, trains with alternative drives are the method of choice on some railway lines. The study provided valuable insights in this regard.”
The question of electrification with an overhead line or vehicles with alternative drives was asked during the study for 16 route sections in Baden-Württemberg, which was awarded to a bidding consortium consisting of TransportTechnologie-Consult Karlsruhe (TTK), komobile (Vienna) and other partners. Three drive technologies were examined – battery hybrid trains, hydrogen hybrid trains and conventional electric trains.
Depending on the drive technology there are different requirements for the infrastructure. The use of classic electrically operated trains requires electrification of the entire route with an overhead line. For the use of battery hybrid trains, however, only the electrification of individual sections is necessary. A corresponding filling station infrastructure or production sites for green hydrogen would have to be set up for the operation of hydrogen hybrid trains.
Infrastructure scenarios were developed for the various drive technologies, the costs incurred were determined and possible route-specific synergy effects were examined. In addition, technical vehicle parameters such as production costs, maintenance costs, the energy requirements of the vehicles and CO2 emissions were examined and considered in the evaluation.
Economic aspects were decisive for the evaluation, but also additional strategic aspects, such as closing the gap between existing routes with overhead lines, possible function in freight traffic or the option for diversion traffic. These were also included in the final recommendation.
According to Baden-Württemberg, operation with hydrogen hybrid trains will no longer be considered for various operational and economic reasons. In a direct comparison, this technology was not able to assert itself on any of the examined routes in Baden-Württemberg, also due to the characteristics of the infrastructure and operation.
Recommendations of the report for the sub-networks examined can be viewed here.