Assessing the Emission Savings Potential of Just-in-time Arrival in the Kiel Canal

Kurzfassung

In many parts of maritime transport, traffic management follows a first-come, first-served (FCFS) principle. While this is a straightforward approach, in dense traffic and when scheduling constraints are present, this often results in vessels arriving too early at port entrances or canal locks, sailing at unnecessarily high speeds and subsequently waiting—typically at anchorage areas or by slow steaming in waiting zones. This practice leads to excess fuel consumption and emissions on the incoming voyage. Just-in-Time (JiT) arrival offers a more efficient alternative, allowing vessels to adjust their sailing speed to align with available slots and thereby minimize waiting. This study investigates the energy-saving potential of JiT arrival in constrained waterways, with the Kiel Canal serving as an illustrative case. Based on Automatic Identification System (AIS) and ship technical data, westbound voyages of different ship types were analyzed on their estimated fuel consumption and waiting times before entering the Kiel canal. By reconstructing the voyages under JiT scenarios the potential reductions in fuel consumption and emissions were quantified. The methodology employs scenarios to quantify the potential fuel and emission savings under different speed and arrival time adjustments. In addition, the effect of the notification time—the moment when vessels are informed about their allocated slot—was analyzed to identify optimal notification time as well as to determine its impact on achievable energy savings for westbound voyages. Results show that JiT arrival can yield significant energy savings and emission reductions, with benefits varying by vessel category. Earlier notification times enhance the potential for energy savings indicating a tradeoff notification time at which energy savings are converging. The findings provide practical insights for implementing JiT concepts and improving traffic management in key maritime corridors.