Comparison on the use of Hybrid and Plugin Hybrid Electric Buses for Sustainable Urban Transportation – Split Use Case

Urban livability faces significant challenges due to trafficcongestion, noise pollution, and vehicle emissions. Electric buses offer apromising solution to reduce noise and tailpipe emissions in cities. How-ever, their limited range, constrained by battery capacity, can hinderoperational flexibility. As an alternative, plug-in hybrid electric busesand hybrid buses (referred as PHEB and HB, respectively) provide amore versatile option by combining zero-emission capabilities with con-ventional diesel engines. Their efficiency depends on battery capacityand the strategic allocation of electric drive sections along routes. Yet,existing electric drive assignment systems remain suboptimal, as they donot fully exploit the potential of hybrid propulsion.The significance of electromibility is highlighted in this work, by an-alyzing the broader environmental benefits and the impact on urbanquality of life of these two main existing technologies, plug-in electrichybrid and electric hybrid. Unlike previous approaches that primarilyemphasize energy efficiency, this work develops optimized strategies formaximizing electric driving distance while minimizing overall emission.The problem is formulated as a multi-objective optimization one, tack-led using a state-of-the-art evolutionary algorithm along with the exist-ing GreenK heuristic. These methods enable the exploration of differentelectric drive distribution scenarios while accounting for real-world trafficconditions and route topography. Results demonstrate that the electro-mobility technology used significantly impacts on sustainability, hybridbuses producing higher tailpipe emission levels (covering 17,9% less dis-tance with the electric motor), but avoiding the need of any charginginfrastructure. In either case, HB or PHB, the optimized electric drivestrategy can significantly reduce emissions and enhance the efficiency ofthe public urban bus networks, contributing to more sustainable publictransportation systems.