by Mikkel Mühldorff Sigurd.

Maersk Line operates a network of approximately 500 container ships sailing on 120 scheduled routes. Larger vessels are deployed on inter-continental main routes typically calling 10-20 main ports on a roundtrip. Smaller vessels are deployed on regional so-called feeder routes, connecting a main port to 1-5 smaller ports within the region. Maersk Line's network thus offers a mixture of direct transportation products between main ports, but also indirect so-called transhipment products between feeder ports, where 1 or more transhipments between routes are necessary. Designing a container shipping line network is a trade-off between offering many fast, direct products to the customers, but at the same time benefitting from the economy of scale by consolidating cargo from many smaller vessels on 1 large vessel on the long haul. Variation in outside factors, such as oil prices, port costs, cost of vessels, and cargo volumes changes the topology and strategy of the network, and thus the task of running an efficient network requires day-to-day monitoring and changes.

We will present Maersk Line's experience with optimization IT tools to assist network designers in doing both smaller and larger changes to Maersk Line's network. Our experience involves both optimization and simulation, which involves other types of optimization problems. Lately, a collaboration with DTU and ITU has been started which aims at developing new methods for container shipping line network design.