Reducing fuel emissions by optimizing speed on shipping routes

Abstract

Fuel consumption and emissions on a shipping route are typically a cubic function of speed. Given a shipping route consisting of a sequence of ports with a time window for the start of service, substantial savings can be achieved by optimizing the speed of each leg. This problem is cast as a non-linear continuous program, which can be solved by a non-linear programming solver. We propose an alternative solution methodology, in which the arrival times are discretized and the problem is solved as a shortest path problem on a directed acyclic graph. Extensive computational results confirm the superiority of the shortest path approach and the potential for fuel savings on shipping routes.

Keywords:

• shipping routes
• fuel emissions
• speed optimization
• shortest paths

Acknowledgements

This research was carried out with financial support from the DESIMAL project, funded by the Research Council of Norway and from the Canadian Natural Engineering Research Council under grant 39682-05. This support is gratefully acknowledged. We are also grateful for valuable comments and suggestions from two reviewers.