Séminaire conjoint CIRRELT-Chaire de recherche du Canada en distributique-Chaire de recherche du Canada en logistique et en transport

TITRE : Green Supply Vessel Operations

CONFÉRENCIER : Ellen Karoline Nørlund, Molde University College, Norvège,

DATE et ENDROIT : 15 avril 2014, 10h30, salle 5441, Pavillon André-Aisenstadt, Campus de l’Université de Montréal

RESPONSABLE : Gilbert Laporte

RÉSUMÉ : The oil and gas industry needs reliable transport of cargo between onshore bases and offshore installations. Each installation requires one or more fairly spread visits throughout the week, and some of the installations are closed at night yielding multiple time windows. The vessels have fixed departure times from the onshore base, and the duration of a voyage is two or three days. The supply vessel planning problem is a fleet mix and periodic vehicle routing and scheduling problem. We study how optimizing sailing speeds when constructing schedules can reduce fuel consumption and thus emissions from the supply vessels operations. A supply vessel weekly schedule may include waiting time for opening hours at installations, waiting for loading and unloading at supply base and idle time between voyages. We develop speed optimization strategies that utilize the waiting time in different ways to reduce speed and hence emissions. The speed optimization strategies are incorporated into a two-phase optimization procedure, where feasible vessel voyages are first generated and the schedule is then constructed by solving an optimization model. A cost minimization objective including vessel charter and voyage fuel costs is used to achieve a weekly schedule with low emissions and minimal number of vessels. Tests carried out on real instances from Statoil’s activities on the Norwegian continental shelf show up to 25% emissions and fuel costs reductions without fleet size increase.