Transit network design: A sustainability-oriented methodology for the management of large bus networks and low emission zones

• A methodology for Transit Network Design integrating routes and frequencies with the strategic deployment of electric buses. • Design of bus transit networks able to manage transition phase from fleet composed by conventional vehicles, usually diesel buses, to electric ones. • This holistic approach aims to enhance operational efficiency, reduce citizens exposure to emissions and ensure a seamless transition to a more sustainable urban public transport system. The present paper proposes a methodology aimed at design bus public network suited to serve high-sensitive zones of the study area with low-impact vehicles. The purpose is to provide a procedure for support a smart electrification of public transport bus network, optimizing the use of electric vehicles where it is most effective to operate them. The new methodology solves a Transit Network Design (TND) problem where the optimization model consists of minimizing costs and resources in a public transport network also including sustainability issues. Therefore, starting from the method presented in Cipriani et al. (2012) , the issue is framed as a multi-objective model, combining two objectives: the classic TND objective and the second related to the identification of the use of electric vehicles where it is most effective to operate them. The complexity of such issues needs metaheuristic algorithms application, in which the GA permits to obtain Pareto optimal non dominated solutions for the TND. Such solutions are then exploited as a multi-objective analysis, treating conventional objectives and objectives for a better use of electric vehicles, separately. The methodology has been implemented in a case study in the city of Rome. The findings demonstrate the effectiveness of methodology to design robust public transport supply system suited to serve high-sensitive zones.