Research project MOSENAS

Modular scalable energy storage for a sustainable rail passenger transportation

Credit:

BMDV

The objective of the project MOSENAS is the development of a battery electric multiple unit for a long-term use on various non-electrified and partially electrified railway lines. The focus is set on the designing of a modularly scalable energy storage system under consideration of operational feasibility, efficiency and compatibility with the surrounding charging infrastructure.

Research project MOSENAS

 

Duration

January 2022 to October 2024

Funded by

Federal Ministry for Digital and Transport

Project participants

  • Stadler Rail Group
  • Institute of Networked Energy Systems
  • Institute of Vehicle Concepts

Electric propulsion offers significant emission advantages in the rail transport as opposed to a diesel engine. However, the layout of all routes with overhead lines mean economic hurdles, or else, is rather difficult to implement due to local restrictions. Still, the near-term upgrade to renewable energy sources within the rail sector can be realized by means of modern battery technologies.

A scalability of the energy storage allows an ideal adjustment to operating conditions of different route profiles and, therefore, diesel multiple units (DMU) can be replaced by battery electric multiple units (BEMUs). In this context, the reliability of a smooth passenger service presents a particular challenge leading to measures to secure energy supply even over several route cycles, if need be.

On the one hand, local topography, recuperation, air conditioning requirements, passenger numbers as well as the availability of charging infrastructure affect the necessary energy storage and power requirements on the battery system and, on the other hand, the lifetime of the batteries. An underdimensioning of the battery storage can result in insufficient states of charge and therefore breakdowns and cancellation of services. An oversizing requires the binding of an unnecessary amount of mass and construction volume with increased need of operating power. At the same time, extra capital is tied up.

In order to address the question on how much battery capacity is needed and which cells are most suitable to secure a safe and efficient operation, a systematic analysis on battery ageing is carried out in the framework of the project. The analysis is supported by a battery measurement campaign. On the basis of battery ageing models, the configuration and dimensioning of a battery system is being optimised. The development of lifetime extending operating strategies will be jointly elaborated on with the DLR-Institute of Vehicle Concepts.

Long times in the driving mode and comparatively short stays at the charging points, for example in stations or depots, require a quick supply of large of electrical energy and a selective enhancement of the charging infrastructure. This shall be guaranteed by appropriate concepts of local grid supplied power, sector integration and the highest possible inclusion of renewable energy.

A further focus of the project lies on the analysis of potential electrification, particularly supplementary electrification of route sections and catenary island systems, and on the optimised system solutions for infrastructure and vehicle combinations. The integration of second use batteries in stationary storage facilities for the purpose of facilitating an economic and robust operation with mitigated effects is examined in this context. A full electrification of the routes serves as a comparing reference. These routes are fully equipped with overhead lines which does not make the operation of a BEMU necessary. However, it causes a significant outlay to upgrade the infrastructure.
In order to increase the use of renewable energy sources within the transport sector, a direct integration of the charging infrastructure with regenerative generation plants (direct and through public grid) is being analysed.

Departments, research groups and challenges related to the MOSENAS project:

Department

Energy Systems Technology

The Energy Systems Technology department focuses on the interaction between system-relevant technologies within decentralised networked structures, particularly at the low-voltage and medium-voltage level.

Research Group

Smart Energy Management

The Smart Energy Management research group develops methods and strategies to optimise the operation and design of future energy systems hand in hand.

Challenge

Balancing energy supply and demand

The simultaneity of electricity generation and consumption is the basis for a stable energy system. While fossil and nuclear power plants have so far been deployed according to demand, the dominant renewable energies in the electricity system are heavily dependent on weather - and therefore not available at any given time.