The synergy between the photovoltaic power systems and battery-powered electric ferries in the isolated energy system of an island

Islands have increased potential to integrate renewable energy sources (RES) into their energy systems and shift towards sustainable decarbonization. The intermittent electricity causes issues such as the mismatch between the energy demand and supply, the grid instability and the electricity price volatility. The integration of the battery-powered electric ferries (BEF) into the isolated energy system (IES) powered with RES can be considered as an economically and environmentally friendly solution for matching the demand with the supply, since all-electric ships can connect to the grid and provide positive or negative balancing power. The carbon dioxide (CO 2 ) emissions from shipping operations can be reduced to zero by utilizing batteries as a power source. This paper deals with a holistic approach that demonstrates opportunities that implementation of BEF offers in the framework of IES of an island. A method for modelling energy supply for a 100% electric ferry transport is developed to reduce the critical excess electricity production (CEEP) from the photovoltaic (PV) power systems. The energy modelling of the IES was carried out in EnergyPLAN program. The results confirmed that synergy between the PV power systems and BEF can significantly reduce the CEEP, the operating system costs and the emissions of CO 2 .