Potential freight distribution improvements using motorways of the sea

[Display omitted] ► Strategies using SSS with RoRo or RoPax ships gain profit with economies of scale. ► SSS–RoPax with unaccompanied cargo is competitive against only-road-haulage. ► Success depends on policies facilitating cooperation between carriers. ► Success depends on: freight price, demand, equipment management and port performance. This paper analyzes how the strategy taken by the cargo carrier when using motorways of the sea (understood as regular roll on/roll off short sea shipping lines) affects the competitiveness of the shipping line. Five different strategies were analyzed and grouped into three main types: road door-to-door transportation, road and sea transportation combined with a driver always accompanying the cargo and road and sea transportation where the cargo travels unaccompanied. The analysis provides formulae to calculate the economical and temporal cost differences from using a sea link in distribution and assesses the risk and investments necessary to maximize the profit for each strategy. The paper ends identifying the critical points affecting the competitiveness of short sea shipping roll on/roll off lines and proposes policies that could help in its development and success.