Energy-Efficient Timetable Optimization

A significant part of the electricity cost incurred by VAG Verkehrs-Aktiengesellschaft Nürnberg is due to the traction energy of the trains in the Nuremberg underground system. These costs can be reduced significantly by optimization the driving behaviour of the trains in an energy-efficient fashion. VAG already undertakes great efforts to educate their drivers to drive economically on the human-operated line U1. Furthermore, the computer-controlled automatic lines U2 and U3 are calibrated in the same fashion. Via the cooperation with the ADA Lovelace Center, the energy-efficiency of the underground system shall be increased further. To this end, we use the remaining degrees of freedom in the timetable planning phase such that on each segment between two stations, the train are operated with optimization velocity profiles. Moreover, the recuperated energy from braking trains shall be used best possible by other accelerating trains. The novelty in the approach lies in the fact the driving behaviour is not optimized for each train individually but in coordination with the behaviour of all other trains such that a global optimum in energy savings can be attained. At the same time, the approach keeps up the high level of service and convenience for the passenger as well as all safety restrictions and further operative requirements. Our results point to six-digit savings in energy costs every year.

©VAG – Claus

Participants: Andreas Bärmann, Patrick Gemander, Lukas Hager