Siemens Mobility, Nahverkehr Westfalen-Lippe (NWL) and Rock Rail have presented the external design of 61 Mireo Plus B battery-electric trains for the Northern Westphalia regional network in Germany. Siemens will manufacture the two-car units, which are scheduled to begin replacing diesel trains in December 2029 under a previously agreed fleet programme.
The design presentation is a milestone within an existing order, not an additional 61-train contract. NWL published the new appearance on 22 October, followed by an English-language Siemens announcement on 26 October. Rock Rail will finance and provide the vehicles for long-term regional use, with their identity maintained even if the company operating the passenger services changes.
Around 7.1 million train kilometres a year are envisaged across East Westphalia-Lippe and Münsterland. NWL calls the investment its largest regional rail modernisation programme and describes the planned fleet as Germany’s second-largest group of battery-electric trains. The scale refers to the contracted fleet and expected service pattern, not completed vehicle deliveries or achieved reductions in diesel use.
A Mireo Plus B is a battery-electric multiple unit able to use overhead power on electrified sections and onboard stored energy where there is no continuous overhead supply. A traction converter and control system manage power to the motors and batteries, while regenerative braking can recover some energy during deceleration. The train therefore needs charging opportunities distributed around the route as well as sufficient stored energy for unelectrified stretches.
Retaining battery operation on unelectrified lines can avoid installing continuous overhead equipment along an entire regional route. Full electrification may require line possessions, structures, substations and clearances that make it expensive or disruptive in particular locations. Battery trains provide a different infrastructure choice, but they still depend on sufficient electrified mileage, charging power and operating time to replenish their energy stores.
Timetable design has to account for gradients, station stops, passenger load, heating and air conditioning, and the length of each interval without a charging supply. Battery state of charge and reserve capacity become operating constraints, particularly during disruption. Siemens has not provided route-specific battery range or consumption figures with the design presentation; nor does locally emission-free traction establish the carbon intensity of the electricity used.
Siemens says the trains are intended to operate more quietly than the diesel fleet they replace. The company has not supplied route-specific measurements of noise reduction or lifecycle carbon savings in the design announcement. Those outcomes will depend on the deployed service pattern, power supply and the vehicles’ eventual operating performance.
NWL’s new livery is intended to give the regional network a recognisable identity independent of the passenger operator. Trains commonly remain in service longer than individual operating contracts, so branding tied to the transport authority can persist as the company providing train services changes. The exterior presentation therefore concerns the long-term management of a financed public transport asset as well as its appearance.
Rock Rail’s financing role separates vehicle ownership and provision from day-to-day passenger operation. That arrangement can keep the same trains allocated to the regional network across successive operating contracts. Maintenance, software configuration and technical acceptance still require coordination with the operator and infrastructure manager; a standard livery alone cannot make the fleet interchangeable between routes.
Passenger specifications include wireless internet access, power and USB sockets, space for 18 bicycles and two wheelchairs, and step-free boarding. Such provisions affect interior engineering as well as capacity planning. Bicycle and wheelchair accommodation have to share finite space with seating, circulation paths, doors and equipment cabinets, while interior power and data services add electrical loads that the auxiliary systems must support.
Further milestones include train manufacture, testing, approval for service, maintenance preparation and confirmation of compatible charging arrangements on the intended routes. The exterior design does not demonstrate that a production fleet has passed acceptance or that the first vehicles are running. Phased entry into service remains planned from December 2029, after those technical and operational steps.
The 61-unit Westphalia-Lippe programme is distinct from other Mireo Plus B orders Siemens has announced in Germany. Its specified network, financing structure and operator-independent identity relate to this particular fleet. In operation, its engineering balance will be between battery capacity, available electrification, charging dwell time and the duty cycle required of a regional timetable.
