Life-cycle cost assessments of different power system configurations to reduce the carbon footprint in the Croatian short-sea shipping sector

In order to comply with stringent environmental regulations, shipbuilders and ship-owners are seeking cleaner fuels and the integration of renewable energy sources into ship power systems. Such solutions regularly result in additional costs for ship operators, both in the case of retrofitting existing ships or acquiring completely new vessels. This paper deals with the life-cycle cost assessments (LCCAs) of different power system configurations of a ro-ro passenger vessel operating in the Croatian short-sea shipping sector. Electrification of the ship is considered as an option to reduce the carbon footprint (CF) of the vessel and to achieve economic savings during its lifetime. In this sense, the ship operational profile is analysed and its total power needs are determined. The life-cycle assessments of an existing diesel engine-powered solution and two potential battery-powered ship options (with and without photovoltaic cells) are performed by means of GREET 2018 software. Furthermore, these options are compared from an economical viewpoint, where different carbon credit scenarios are investigated. The results show that a diesel engine-powered vessel has the highest carbon footprint, as expected. However, it is also found that a battery-powered vessel (with or without photovoltaic cells) has a minimum environmental footprint and at the same time represents economically the most favourable solution for all possible carbon allowance scenarios. This indicates that all-electric ships seem to be a promising option for the future development of the Croatian short-sea shipping sector.