Fuels for short sea shipping: A comparative assessment with focus on environmental impact

Artikel i vetenskaplig tidskrift, 2014

Short sea shipping is facing harder requirements on exhaust emissions in the coming years as stricter regulations are enforced in some regions of the world. In addition, shortage of conventional fuels as well as restrictions on greenhouse gas emissions makes the search for new fuels of interest. The objective of this article is to assess important characteristics to evaluate when selecting fuels for short sea shipping. The following four criteria are considered: (1) local and regional environmental impacts, (2) overall environmental impact, (3) infrastructure and (4) fuel cost and competition with other transport modes. Special focus is put on environmental impact, and life cycle assessment is used for the environmental assessment. The fuels compared in this study are heavy fuel oil, marine gas oil, biomass-to-liquid fuel, rapeseed methyl ester, liquefied natural gas and liquefied biogas. This study shows that liquefied natural gas will reduce the local and regional environmental impacts more relative to the other fuels investigated here. Furthermore, liquefied biogas is found to be the most preferable if all envirtsonmental impact categories are considered. This study also highlights the importance to consider other impact categories for short sea shipping compared to deep sea shipping and shows that NOX emission is the dominant contributor to all assessed environmental impact categories with local and regional impac