Holistic view to decarbonising cruise ships with a combination of energy saving technologies and hydrogen as fuel

• Decarbonisation of cruise ship is studied utilising operational patterns from existing cruise ship. • Several technologies are working in symbiosis for ship decarbonisation. • Hydrogen fueled combustion engine machinery is simulated for the ship • Synergies between technologies and hydrogen machinery save additional energy. • Holistic analysis focuses on energies, fuel, carbon emissions and ship EEDI and CII. Cruise ship decarbonisation was studied on a Mediterranean cruise profile. The analysis focused on ship energy flows, fuel consumption, carbon emissions, ship CII and EEDI. A combination of technologies for reducing ship fuel consumption was simulated before introducing hydrogen fueled machinery for the ship. The studied technologies included ultrasound antifouling, shore power, battery hybrid machinery, waste heat recovery and air lubrication. Their application on the selected operational profile led to combined fuel savings of 18,7%. When the same technologies were combined to a hydrogen machinery, the ship total energy consumption, compared to baseline was reduced by 25%. The cause of this was the synergies in the ship energy system, such as ship auxiliary powers, heat consumption and machinery efficiency. The proposed methodology of ship energy analysis is important step in starting to evaluate new fuels for ships and in preliminary technology screening prior to integrating them in the ship design.