A multi-trip electric bus routing model considering equity during short-notice evacuations

Abstract

Widespread use of electric vehicles (EVs) and electric buses (EBs) adds new challenges to short-notice evacuations. Studies modeling EV behavior suggest that the power grid in most cases cannot handle EV demand during the evacuation preparation stage, but ignore the potential efficiencies of coordinated EBs. To overcome this shortcoming, a generalized framework based on three multi-trip EB routing models is developed to a) estimate the feasibility of using EBs during short-notice evacuations by examining evacuation efficiency, b) analyze EB charging behavior considering evacuation efficiency and path assignment equity, and c) explore the economic advantages of using EBs by comparing EBs with conventional liquefied natural gas (LNG) buses in terms of efficiency and operational cost. A genetic algorithm with an improved recombination strategy (GA-IR) is developed to solve these models. Computational results show that GA-IR outperforms GA in terms of convergence speed and solution quality, as GA-IR takes into account the empty trip removal process and the charging station re-insertion process, which is an innovation of GA-IR. Sensitivity analysis shows that using k-means clustering to position charging stations, and increasing the number of charging stations and EBs can improve evacuation efficiency.