ABSTRACT
This chapter discusses the methodologies and calculation procedures presented in the literature for assessing external costs implied by intermodal transport chains, with particular focus on the specific features of its application to short sea shipping (SSS) using roll-on/roll-off (Ro-Ro) ships. This evaluation of costs is included in an integrated methodology for the economic assessment of SSS routes, which is supported by a transport network model. The methodology and associated numerical methods are applied in a case study to evaluate the competitiveness of different SSS Ro-Ro routes in comparison with road and rail alternatives, with and without the full internalization of external costs and considering various possible ports. External costs associated with emissions are calculated using an activity-based approach. The case study indicates the detrimental effect of ship speed and of the significant emission factors associated with current marine fuels in the volume of emissions and in the external costs. Maritime route adjustments are carried out with positive effects in performance. The conclusions obtained may support decisions from shipping companies and guide port and national authorities in the development of transport infrastructure and in deciding whether to grant appropriate levels of public funding.
