Alternative fuels and propulsion systems for fishing vessels

Abstract

The main objective of CoolFish is to increase energy efficiency of the utility systems (cooling, freezing and heating) onboard fishing vessels. To achieve a full potential of efficiency and environmental benefits the ship must be considered as an engineering system, i.e. also considering the propulsion system. Stricter environmental regulations and an increased awareness of energy use and emissions force the shipping sector to adapt new fuels and/or propulsion systems to replace the conventional mechanical diesel engines. This report provides an overview on such alternatives with focus on new-built and ordered Norwegian fishing vessels. The review shows a development towards diesel-electric or hybrid propulsion systems, often with hybrid power supply (e.g. batteries). Hybrid propulsion and hybrid power supply enables several operating modes, to match speed and auxiliary requirements, enabling flexible and fuel-efficient operation. However, it also implies challenges in relation to waste heat availability and sizing of heating and cooling equipment. Alternative fuels with high technical feasibility for the fishing sector include LNG/LBG and biodiesel for all fishing vessel types, and hydrogen fuel cells for coastal fishing ships. Battery implementations for partly electrified propulsion are considered highly feasible for the whole fishing sector.