CO2 Emission and Fuel Consumption Evaluation for Variable-Speed Diesel Generators and DC grids for Ship Power Systems

This paper aims at investigating the CO2 emission, the fuel consumption, the energy contribution and the time connection of each generator in standards routes of a Platform Supply Vessel (PSV) using direct-current (DC) distribution system. Since the majority of the PSVs work with AC distribution grids, in this paper we trace a comparison between both distribution systems. The PSV has four 1850kW diesel generators, two 450kW auxiliary diesel generators and two batteries. The diesel generators operate at variable speed through an AC-DC converter and the batteries are connected to the DC grid through a DC-DC converter. The propulsion system is connected to the AC grid through an AC-DC-AC converter and is composed by two bow thrusters and two azimuth thrusters, The base loads and the service loads represents the other loads that a ship can have such as GPS, radars, hospitality and lighting. The results of this paper are obtained with HOMER energy. Moreover, the benefits obtained of operating the PSV's with DC distribution system are enumerated.