Performance Analysis of Innovative Propulsion Systems for Short-Haul Ferries

Antipollution regulations for marine applications have become increasingly stringent in recent years, with the International Maritime Organization (IMO) setting ambitious limitations for the coming years: a 70–80% reduction in greenhouse gases (GHGs) by 2040 and approximately net-zero by 2050. To meet these targets, a lot of research has been focused on developing both more efficient engines, powered by sustainable fuels, and electrified propulsion systems, especially for short-range marine applications. These systems combine internal combustion engines and electric motors to optimize the overall efficiency, improving both energy consumption (EC) and polluting emissions. In this study, three different propulsion system architectures are compared, which could be installed on a ferry traveling along a mission profile, typical of a line operating within the Venice Lagoon, in Italy. The comparison between an application with only a hydrogen combustion engine, an application with a hybrid propulsion system, and a fully electric application clearly highlights advantages and limitations in terms of consumption, weight, and, consequently, transportable payload. In fact, since the ferry's total mass remains constant, the choice of the type of propulsion system has a significant impact on both energy expenditure and transportable mass, i.e., on the maximum number of passengers that can be transported.