On the Possible Introduction of Mini Gas Turbine Cycles Onboard Ships for Heat and Power Generation

The recent coming in force of MARPOL 2020 restrictions on shipping pollutant emissions highlights a growing interest in current times towards cleaner means of transport. One way to achieve more sustainable vessels is represented by updating onboard engines to suit current regulations and needs: Gas Turbines are not a novelty in the field and, despite the few applications in commercial shipping so far, this technology is again under evaluation for different reasons. Indeed, it is still a preferred choice in navy, where swift maneuvering is a key factor; it is employed by fast ferries and hydrofoils for its high power/weight ratio; it has been recently applied to LNG carriers to burn boil-off gas in a more efficient way and several studies in literature suggest its possible introduction on large Cruise Ships. Since there seems to be a lack of research concerning small size units, the present work attempts to evaluate the possible usages of Mini Gas Turbine Cycles in the range of 1 to 10 MW of electric output for heat and power generation onboard commercial vessels dedicated to passenger transport. For this purpose, a statistical analysis on existing operating vessels up to 2020 was made, to eplore main engine sizes; a literature review was carried out to find representative onboard heat demands. Once the main vessel electrical and thermal requirements were evaluated, Mini Cogenerative plants based on Gas Turbines were designed within the identified boundaries and compared with state-of-the-art Marine Diesel Engines and Gas Turbines on estimated global performance, dimensions and weights.