An intense innovation activity is characterizing the energy system solutions on board ships, especially in the case of large passenger ships due to the significant total amount of installed power and the variegate typology of electrical loads. In the paper the solution of a distributed energy system will be considered for a 140.000+ GT cruise ship, in the perspective of a superior performance in terms of safety and energy efficiency. The target is to overcome the traditional concept of power generation based on large diesel Gensets located in few compartments. The innovative proposal is to integrate it, for the hotel needs, with a greater number of power generation units (but of a smaller size), properly distributed on board. For the application, a suitable reference cruise ship vessel will be considered, already characterized by LNG propulsion solution. Number, typology, size and integration on board of the generation units will be defined in relation with aspects of zonal independence, electrical load, weights, volumes, fuel tanks, supply systems, auxiliaries, with the minimum possible impact on commercially valuable space. In this perspective, fuel cells technology will be particularly taken into account. The critical issues in relation with the present safety rules and the whole ship design process will be addressed as a fundamental aspect.