Co-hub charging planning for electric bus and paratransit using fuzzy multi-objective optimization

Paratransit, a demand-responsive transit mode serving passengers with mobility challenges, is increasingly electrified to enhance urban transportation sustainability. However, high investments required for dedicated charging infrastructure and the scarcity of public charging resources remain significant hurdles to large-scale deployment. This study investigates a shared charging scheme that integrates paratransit electric vehicles (EVs) into existing electric bus (EB) charging networks. A fuzzy multi-objective optimization framework is proposed to identify optimal charging co-hub locations and EV assignments by balancing supply–demand dynamics. The framework incorporates two-step floating catchment area (2SFCA) and inverted 2SFCA (i2SFCA) methods to formulate objectives and constraints for EB and paratransit systems, respectively. Through fuzzy programming, trade-offs among supply–demand dynamics are resolved, yielding efficient shared-charging plans. The framework is validated with Utah Transit Authority data, demonstrating improved charging accessibility and operational efficiency while offering actionable insights for transit agencies in planning shared charging schemes among various public transport modes.