Decarbonising campus transportation through electric bus fleet electrification: resource and environmental implications

The electrification of the university bus fleet presents a practical pathway to make campus transportation free from emissions. Diesel buses are mostly utilised in the campus for students’ transportation from various buildings. To make the campus more environmentally friendly, diesel buses to be replaced with electric buses. This study develops a mixed integer programming framework to support long-term strategic planning for replacing diesel buses with electric buses. The developed model optimises the replacement decision of buses and new charger installation over a 20-horizon period while considering multiple constraints. Unlike existing studies, the model incorporates dynamic pricing of energy and maintenance prices and provides sensitivity analysis of early battery retirement. The proposed model is applied to the transit KFUPM transportation from diesel buses to electric. The results demonstrate that with a total discounted cost of 19.14 $ million, 100% electrification of the fleet is achieved. The model also estimated a 41% reduction in carbon emissions if the conventional buses are replaced. Additionally, if the grid emission factor is reduced due to more renewable sources, the total emissions over the planning period will reduce by 46%. The model offers a decision support tool for universities seeking a green campus with optimal transportation.