  This article presents an optimization-based approach for sizing and
composition of an Arctic offshore drilling support fleet considering
cost-efficiency. The approach studies the main types of duties related to
Arctic offshore drillings: supply, towing, anchor handling, standby, oil spill
response, firefighting, and ice management. The approach considers the combined
effect of the expected costs of accidental events, the versatility of
individual support vessels, and ice management. The approach applies an
Artificial Bee Colony algorithm-based optimization procedure. As demonstrated
through case studies, the approach may help to find a range of cost-efficient
fleet compositions. Some of the obtained solutions are similar to corresponding
real-life fleets, indicating that the approach works in principle. Sensitivity
analyses indicate that the consideration of the expected costs from accidental
events significantly impacts the obtained solution, and that investments to
reduce these costs may improve the overall cost-efficiency of an Arctic
offshore drilling support fleet.
