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arXiv · 2605.02355

Optimizing Travel Time and Regenerative Energy for Periodic Timetables

Sarah Roth·Sven Jäger·Niels Lindner·Anita Schöbel
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Abstract

Regenerating braking energy is one major pathway to make rail traffic energy-efficient. It is therefore desirable to design timetables that exploit this feature. However, timetables that allow to regenerate energy are often bad for the passengers. We hence formulate and analyze a bicriteria optimization problem (PESP-Passenger-Energy) to find periodic railway timetables that maximize the regenerated energy in terms of the brake-traction overlap time and minimize the travel time of the passengers. Our model extends the Periodic Event Scheduling Problem (PESP) and offers a rich combinatorial theory. We investigate its computational complexity on one-station networks, building on matchings and Hamiltonian paths. Besides showing its NP-hardness even for a single objective, we identify several polynomial-time solvable special cases. Finally, we provide two case studies, underlining the practicability of our model, and analyzing the Pareto front.

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Sarah Roth, Sven Jäger, Niels Lindner, Anita Schöbel. 2026-05-04. Optimizing Travel Time and Regenerative Energy for Periodic Timetables. https://arxiv.org/abs/2605.02355

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