The supply of the loading infrastructure for an increasing share of electrically powered vehicles leads to new challenges for distribution grid operators. Especially the additional power for loading processes needs to be provided without any influence on the security of supply. At the same time, it is important to minimize expensive modernization measures for all grid components.
For this reason, the influence of a significant share of electrically powered vehicles on the distribution grid of Hamburg was investigated in the “Meta Study Electromobility”. The focus of this examination was the utilization of the approximately 50 transformer stations, each of which supply a defined area of Hamburg with a medium voltage grid. An additional focus was on the transition of the bus fleets of the Hamburger Hochbahn AG (HOCHBAHN) and Verkehrsbetriebe Hamburg-Holstein (VHH) towards purely electrically powered bus fleets.
A new market forecast for electrically powered vehicles, called “META”, was defined and compared to other expected market developments (figure 1). A corridor was formed to analyze the impact of deviations of the scenario “META” on the grid. The market scenarios “MIN” and “MAX” limit this corridor.
Figure 2 depicts the temporal development of the additional electric power needed due to charging processes. In figure 3 the temporal development of the reserve capacities of transformer stations is shown. This figure gives an overview of the transformer stations and the time horizon for a demand for action. For example the need of an upgrade, because the actual reserve capacity reaches its limit due to the assumed market scenario.
Furthermore, the meta study contains investigations of the impact on a transition of the bus fleets of HOCHBAHN and VHH towards purely electrically powered bus fleets. First, a rough deduction of the needed connection capacities of the bus depots in Hamburg caused by the additional power demand was carried out. Afterwards, the saving potentials of the connection capacities by partial usage of hydrogen busses were examined. Figure 4 shows a typical course of the charging capacity of a bus depot for a working week. Moreover, an assessment of battery states of charge and capacities (figure 5 and 6) as well as an investigation of the impact on the availability of electro busses on the bus depot were conducted in the meta study.
Please find more details und further results (in german) in the Meta Study Electromobility
This meta study was commissioned by and accomplished with the help of Stromnetz Hamburg GmbH, Hamburger Hochbahn AG and Verkehrsbetriebe Hamburg-Holstein GmbH (VHH).
 Dietmannsberger, M.; Meyer, M. F.; Schumann, M.; Schulz, D. (Hrsg.): Metastudie Elektromobilität – Anforderungen an das Stromnetz durch Elektromobilität, insbesondere Elektrobusse, in Hamburg; Hamburg; 09.12.2016; ISBN 978-3-86818-095-4
Prof. Dr.-Ing. habil. Detlef Schulz (Projektleiter)
Marc Florian Meyer, M.Sc
Department of Electrical Engineering
Chair of Electrical Power Systems
Letzte Änderung: 19. June 2020