The share of electric vehicles is planned to increase to more than 90% in the year 2045. Consequently, the capacity of the energy grid must be accordingly extended. For predicting future loading needs in the cities of Ulm [KD1] / Neu-Ulm (Germany) and projecting them onto the existing energy grid, a tool chain has been realized, described herein. The resulting simulation system computes the charging needs and interactions between the grid and the vehicle fleet on a disaggregated level of single vehicles, their stops – locations and durations –, and single lines from the cities’ energy grid. The results are assumed to help the authorities responsible for the energy grid to plan necessary extensions.