**7. Conclusions**

A unique city bus transport electrification tool has been presented, which relies on virtual simulation of conventional and e-bus fleets over recorded driving cycles, including charging management. The tool allows for arbitrary setting of charging station locations, number and parameters of chargers per each station, grid constraints, e-bus battery capacity and similar factors. A special emphasis was on providing a computationally efficient, multiple-maps-based backward looking e-bus model including the vehicle control strategy and heuristic charging management algorithm. In support of electrification planning and decision making, the tool finally provides the total cost of ownership (TCO) of city bus fleets with conventional (CONV) buses and different types of e-buses (HEV, PHEV and BEV). It has been demonstrated through a pilot study related to city bus transport in Dubrovnik, based on which the following main conclusions are drawn.


The future work could be directed to the following tool improvements: (i) optimisation of charging system configuration (e.g., by using genetic algorithm) instead of using the expert knowledge when repeating the virtual simulations for different configurations; (ii) using parallel computing to further increase the numerical efficiency of virtual simulations, particularly when optimisation loop is added; (iii) off-line route rescheduling to avoid or mitigate the use of reserve buses in the BEV case or to redirect the e-buses to designated location for daily recharging; (iv) performing city bus transport electrification analyses using limited set of standard GPS/GPRS tracking data while relying more on the bus schedules; (v) considering other economic models when conducting techno-economic analyses to determine the TCO.

**Author Contributions:** Conceptualisation, J.T., B.Š. and J.D.; Methodology, J.T., J.S., F.M. and J.D.; Software, J.T., J.S. and F.M.; Validation, J.T., J.S., F.M. and J.D.; Writing—Original Draft Preparation, J.T., J.S., F.M. and J.D.; Writing—Review and Editing, J.D.; Visualisation, J.T., J.S. and F.M.; Supervision, B.Š. and J.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** It is gratefully acknowledged that this work was supported by the EU European Regional Development Fund trough Interreg CE project SOLEZ ("Smart Solutions supporting Low Emission Zones and other low-carbon mobility policies in EU cities"; https://www.interreg-central.eu/Content.Node/SOLEZ.html).

**Acknowledgments:** In addition, the research work of the first author has been supported by the European Regional Development Fund under the grant KK.01.1.1.01.0009 (DATACROSS). The authors' appreciation also goes to the city bus transport company Libertas Dubrovnik d.o.o. and the Dubrovnik Development Agency (DURA) for the data support and effective cooperation.

**Conflicts of Interest:** The authors declare no conflict of interest.
