Heuristic Solutions to the Single Depot Electric Vehicle Scheduling Problem with Next Day Operability Constraints

TL;DR

This paper presents a two-step heuristic approach for scheduling electric buses with next-day operability constraints, demonstrating near-complete electrification feasibility for Chicago and Austin transit systems.

Contribution

It introduces a novel two-step solution combining VSP and block chaining to efficiently schedule EVs with recharging and next-day constraints.

Findings

Near 100% electrification feasible for Chicago and Austin transit buses.

Requires approximately 1.6 EVs per diesel vehicle at 150-mile range.

Effective scheduling model accommodates recharging and operability constraints.

Abstract

This study focuses on the single depot electric vehicle scheduling problem (SDEVSP) within the broader context of the vehicle scheduling problem (VSP). By developing an effective scheduling model using mixed-integer linear programming, we generate bus blocks that accommodate electric vehicles (EVs), ensuring successful completion of each block while considering recharging requirements between blocks and during off-hours. Next day operability constraints are also incorporated, allowing for seamless repetition of blocks on subsequent days. The SDEVSP is known to be computationally complex, deriving optimal solutions unattainable for large-scale problems within reasonable timeframes. To address this, we propose a two-step solution approach: first solving the single depot VSP, and then addressing the block chaining problem (BCP) using the blocks generated in the first step. The BCP focuses on optimizing block combinations to facilitate recharging between consecutive blocks, considering operational constraints. A case study conducted reveals that nearly 100% electrification for Chicago, IL and Austin, TX transit buses is viable yet requires 1.6 EVs at 150-mile range per diesel vehicle.