Mireo Plus H trains are next-generation, hydrogen fuel cell-powered passenger trains developed by Siemens Mobility, to replace diesel-powered commuter trains and enable zero carbon dioxide (CO2) emissions in rail transportation.
Siemens Mobility is a separately managed company of German multinational conglomerate Siemens. It developed the new trains in partnership with Deutsche Bahn (DB), a German railway operator, under the H2goesRail joint project, which is focused on decarbonisation to ensure a cleaner future for German rail transport.
Siemens Mobility and DB unveiled the Mireo Plus H and a new hydrogen storage tank trailer at the Siemens Mobility plant in Krefeld, Germany, in May 2022. Designed by DB, the hydrogen storage tank trailer is equipped with a smart control unit to enable fast refuelling of hydrogen trains.
The hydrogen-powered train is part of the Siemens Mireo class of trains.
Testing of the new train is expected to begin in Baden-Württemberg in 2023, followed by commercial operations on the route between Tübingen, Horb, and Pforzheim in 2024.
Specifications of Mireo Plus H
Mireo Plus H is a second-generation hydrogen train, based on a hybrid technology consisting of a fuel cell drive system and a lithium-ion battery pack.
The train can be operated independently of an overhead contact line and is powered by hydrogen generated from renewable sources.
The train will initially have two- and three-car units and can reach speeds of up to 160km/h. It is equipped with a traction power of 1.7MW to provide high acceleration of up to 1.1m/s².
The two-car configuration is expected to offer a range of up to 800km while the range of the three-car configuration is expected to be between 800km and 1,000km. The refuelling of the hydrogen train is expected to take less than 15 minutes.
Hydrogen is stored in tanks placed on the train’s roof to feed the fuel cell system to generate electricity to drive the train. The tanks feature Type IV pressure cylinders and are protected by a closed cover to prevent mechanical damage, as well as the negative impact of ultra-violet (UV) rays. The lithium-ion traction battery system uses regenerative braking technology to store excess energy from the braking operation to be used later to power the train.
A gas handling-unit (GHU) measures the tank system’s pressure and temperature while also indicating its filling level. A smart interface enables communication between the train and the filling station to maintain the fuel supply.
The fuel cells used in Mireo Plus H are claimed to have twice as much power density when compared to conventional fuel cell systems.
The wheels are driven directly without cardan shafts. The converter-fed induction generators receive energy from the fuel cell and/or the high-performance traction battery and use it to drive the wheels. The hydrogen fuel cell system charges the battery and supplies electricity for the onboard systems during normal operations.
Design and features of the hydrogen-powered train
The train has been designed with improved aerodynamics and welded and integral lightweight aluminium, making it one of the lightest-weight trains.
Built with a modern design, it is expected to include spacious interiors. Each car will have three doors on each side. Passenger amenities will include free Wi-Fi and real-time passenger information display systems.
The train will also offer a specially designated family area, and two multi-purpose areas which can accommodate buggies, wheelchairs, and up to 12 bicycles.
A new signage system onboard the train will also help to provide easy and barrier-free passenger exchanges.
Mireo Plus H development details
Siemens received the funding approval from the German Federal Ministry for Transportation and Digital Infrastructure (BMVI) for the development of a fuel cell drive for the Siemens Mireo train platform in February 2018.
The company partnered with Ballard Power Systems, a Canadian fuel cells manufacturer, and RWTH Aachen University on the fuel cell research and development project, which involved the development of next-generation fuel cells with a high power density and long life, with improved efficiency.
The partnership secured €13.74m ($14.49m) in funding from BMVI as part of its National Hydrogen and Fuel Cell Technology Innovation Program.
Siemens Mobility signed an agreement with Siemens Energy, a spin-off of Siemens, for the joint development of an electrolysis and fuelling solution to quickly fuel hydrogen trains in October 2020.
DB Energie, a business unit of DB, will supply the hydrogen required to support the operation of the new trains. The hydrogen will be produced using electrolysis in DB Energie’s mobile filling station at the DB Regio plant in Tübingen, in southwest Germany.
The maintenance of Mireo Plus H will be handled by the DB Regio workshop in Ulm. The workshop will be transformed into a maintenance hub and will be manned by trained DB Regio staff with the support of Siemens Mobility employees.
The Mireo Plus H train’s hydrogen drive system will provide higher efficiency and performance, compared to conventional drives.
Besides ensuring emission-free operation, the hydrogen drives are expected to provide quieter operation compared to conventional combustion engines.
The train is expected to have a long range and produce reduced maintenance and lifecycle costs. It is estimated to offset approximately 520t of CO2 a year.
Orders and deliveries
Bayerische Regiobahn (BRB), a German rail operator, signed a leasing contract with Siemens Mobility in March 2022 for a two-car hydrogen-powered trainset to be operated on its rail network, as part of a pilot project.
Starting from mid-2023, the train is expected to be tested on the Augsburg-Füssen route in Bavaria and other routes on BRB’s network. The Siemens hydrogen train is expected to commence commercial operations in January 2024 and run for 30 months, as part of the pilot operation.
Siemens Mobility ordered two 200kW fuel cell modules from Ballard Power Systems to power the Mireo Plus H train for the trial operation.
Niederbarnimer Eisenbahn (NEB), a local railway operator, placed an order with Siemens Mobility to manufacture and supply seven two-car Mireo Plus H trains in June 2022. Deliveries are expected to take place in Fall 2024, with service entry planned to occur in December the same year. The trains will run on the Heidekrautbahn network (RB27) in the Berlin-Brandenburg metropolitan region.
The order also requires Siemens Mobility to provide service and spare parts until 2034.