Greening of Inland and Coastal Ships in Europe by Means of Retrofitting: State of the Art and Scenarios

This paper analyzes the potential of retrofitting in “greening” of European inland vessels and coastal ships, which are normally not the focus of major international environmental policies aimed at waterborne transport. Therefore, greening of the examined fleets would result, for the most part, in additional emission reductions to the environmental targets put forth by the International Maritime Organization. By scoping past and ongoing pilot projects, the most prominent retrofit trends in the greening of inland and coastal ships are identified. Assuming a scenario in which the observed trends are scaled up to the fleet level, the possible emission abatement is estimated (both on the tank-to-wake and well-to-wake bases), as well as the capital and operational costs associated with the retrofit. Therefore, the paper shows what can be achieved in terms of greening if the current trends are followed. The results show that the term “greening” may take a significantly different meaning contingent on the approaches, perspectives, and targets considered. The total costs of a retrofit of a single vessel may be excessively high; however, the costs may significantly vary depending on the vessel power requirements, operational profile, and technology applied. While some trends are worth following (electrification of ferries and small inland passenger ships), others may be too cost-intensive and not satisfactorily efficient in terms of emissions reduction (retrofit of offshore supply vessels with dual-fuel methanol engines). Nevertheless, the assessment of different retrofit technologies strongly depends on the adopted criteria, including but not limited to the total cost of the retrofit of the entire fleet segment, cost of the retrofit of a single vessel, emission abatement achieved by the retrofit of a fleet segment, average emission abatement per retrofitted vessel, and cost of abatement of one ton of greenhouse gases, etc.