Deployment and retrofit strategy for rubber-tyred gantry cranes considering carbon emissions

Abstract

Driven by green port initiatives, container terminal operators have been substituting environmentally and economically inefficient diesel-powered rubber-tyred gantry cranes (RTGs) with new or retrofitted electric ones. Such an investment is closely related to operational activities, and the process of retrofitting should be carried out under the premise of satisfying the terminal yard container handling requirement. An integer programming model is proposed to help decision-makers determine the investment timing and deploy available RTGs to achieve a CO2 emissions reduction target. Considering the distinctive characteristics of different types of RTGs, we develop a deployment plan as well as an RTGs purchase and retrofit strategy. Moreover, the decisions satisfy an operation workload requirement. A tailored Corridor Method (CM) is used to accommodate large scale real-world instances. The application is illustrated with a modestly sized container terminal yard. Results confirm that electrifying diesel-powered RTGs is effective in curbing CO2 emissions and reducing energy costs. Our numerical experiments also highlight the importance of an appropriate emissions reduction target.