Battery replenishment and repositioning problem in electric barge networks

Electric barge propulsion in Europe is gaining traction as a sustainable solution for reducing carbon emissions in inland waterway transport, with innovations such as swappable batteries taking center-stage. This research addresses the battery replenishment and repositioning problem (BRRP) within an inland electric barge service network. Electric barges equipped with swappable battery technology can carry multiple battery containers in designated onboard docking stations, but use only one at a time for propulsion, creating challenges related to various battery replenishment actions barges can undertake. Additionally, barges can transport extra battery containers as cargo to meet the replenishment needs of other barges in the network. Thus, BRRP examines the dual challenge of using battery containers for propulsion and repositioning them to fulfill energy demands. The study further explores the role of external modes, such as trucks, in battery repositioning. By leveraging the inherent structure of the problem, we propose a novel two-phase solution approach, resulting in an Integer Linear program solvable using commercially available optimization software. Numerical findings reveal an interdependence between replenishment decisions and repositioning strategies, highlighting a trade-off between battery investment and repositioning costs. The results further highlight that both a decentralized charging strategy and charging during system operation reduce battery investment costs, though infrastructure development must be carefully planned. Moreover, while a hybrid repositioning approach generally achieves the lowest system costs across all charging location configurations, each repositioning mode has a specific charging location configuration that minimizes system costs most effectively.