Cities in Charge - Development of public charging infrastructure for electric vehicles in German conurbations (2018-2020)

Interdisciplinary collaborative project in the context of “Sofortprogramm Saubere Luft 2017 bis 2020”

The project Cities in Charge consists of the Telekom Subsidiary Comfortcharge GmbH, Fraunhofer IFAM, three institutes of the RWTH Aachen University, and the city of Dresden. The consortium’s overall objective is to develop charging infrastructure in German conurbations and their surrounding areas. The cities of Bonn, Dresden, Düsseldorf, Hamburg, Hanover, Cologne, and Munich suffer from increased air pollution. Hence, a growth in electric vehicles should contribute to the reduction of NOx-emissions in these regions. In detail, plans are to establish publicly accessible charging infrastructure on Telekom properties in these cities and at the respective connections to the surrounding area. The charging offer will be designed in such a way that existing barriers to the use of electric vehicles are reduced, as charging infrastructure is currently perceived inadequate or inappropriate.

The participating chairs of the RWTH Aachen University take over the following tasks:

The Chair and Institute of Urban and Transport Planning (ISB) investigates the interaction of spatial and transport infrastructure with people's mobility needs. The specially developed modelling approach STELLA – a location model for electrical charging infrastructure – aims at determining the number of charging points, the required charging power, and the expected load factor on a fine-scale basis in consideration of both premises area and demand coverage. Therefore, user characteristics, transport infrastructure with traffic interdependencies, and the resulting traffic congestions are considered as well as spatial analyses with a resolution level up to city quarters.

The Human-Computer Interaction Center (HCIC) explores potential users’ requirements with regard to specific user groups contributing to the design and optimization of the newly established charging and service offer. The focus is set on requirements and potential trade-offs concerning the willingness to use the charging infrastructure. By means of empirically determined and locatable user profiles it is then possible to parameterize the site assessment model (ISB) and derive recommendations for action concerning the nationwide and demand-oriented development of charging infrastructure based on electromobility and charging behavior as well as site preferences.

The Institute for High Voltage Technology (IFHT) investigates the effects of charging infrastructure on the load on distribution networks in various scenarios of current and future supply tasks as well as benefits of intelligent charging strategies and innovative grid management concepts to avoid grid overloads. With regard to the cities of interest, electricity grid analyses are conducted on the basis of grid models. A grid generator is developed which creates representative, georeferenced, and synthetic data based on, among other things, operator-specific grid structure characteristics.

With regard to the RWTH partners, the collaborative goal is to reach a detailed and future-oriented consideration of the overall mobility containing a more detailed analysis of electromobility and the required charging infrastructure.

Project information


Federal Ministry for Economic Affairs and Energy

Funding period:

01.08.2018 – 30.09.2020


Ralf Philipsen

Hannah Biermann

Project partner:

Comfortcharge GmbH

Fraunhofer-Institut für Fertigungstechnik und Angewandte Materialforschung (IFAM)

Lehrstuhl und Institut für Stadtbauwesen und Stadtverkehr (ISB)

RWTH Aachen Lehrstuhl für Communication Science

Human-Computer Interaction Center (HCIC)

RWTH Aachen Lehrstuhl und Institut für Hochspannungstechnik (IFHT)

Landeshauptstadt Dresden