Cruise ship optimal power plants design identification and quantitative safety assessment

The stringent regulatory framework for both emissions and safety as well as the market pressure to reduce the operational costs led the cruise ship industry to pursue alternative solutions. In this respect, multi-objective optimisation methods can be employed for decision-making for identifying optimal solutions with improved efficiency, lower environmental footprint, lifecycle cost as well as a safety level during the ship design phase. In this study, the optimal power plant solutions for an existing cruise ship are compared in terms of their Probability of Blackout (PoB). For this purpose, a novel power plant bi-objective optimisation method has been used whilst considering an actual cruise ship operational profile, a number of design parameters and alternative configurations. Then a Combinatorial Approach for Safety Assessment (CASA) that includes System-Theoretic Process Analysis, Event Sequence Identification and Fault Tree Analysis whilst taking into account a number of design parameters and historical data has been employed to estimate and compare PoB for derived optimal cruise ship power plant configurations. The results demonstrate that the cruise ship power plant configurations with dual fuel engines exhibit lower lifecycle cost and lifetime CO2 emissions. Furthermore, the results demonstrate that power plant configurations with lower redudancy can have similar PoB