Enhancing the diesel generator’s fuel efficiency is a result of the DC distribution system. Thus, the aim is optimizing the diesel generator’s fuel in accordance with its specific fuel requirements. This study focuses on the comparative analysis of the fuel oil consumption (FOC) of diesel generators employing the particle swarm optimization (PSO) technique in two distinct configurations: a radial DC distribution system and a zonal type. These configurations are specifically designed for trimaran vessels that are powered by hybrid electricity. Simulations are conducted to assess the ship’s operation during sailing. The PSO optimization approach was employed to simulate a DC distribution system, encompassing both radial and zonal kinds. Load factors were assigned to each generator based on their respective classifications. The application of particle swarm optimization (PSO) has proven to be effective in optimizing fuel oil consumption on both radial and zonal types of DC distribution systems. The findings indicate that the zonal distribution system exhibits superior fuel efficiency compared to the radial distribution system.