In July 2011 the International Maritime Organization (IMO) defined important changes to the Annex VI of MARPOL Convention, to reduce the CO2 emissions of ships, especially during the port callas. In particular a new Energy Efficiency Index and a Ship Energy Efficiency Management Plan have been defined and will enter into force on the 1st January 2013.
The new measures decided by IMO impose new and more restrict rules to the ship design and the respect of new and more pressing restrictions during the operative stage of ships. This second aspect is more stringent and conflicts with the market rules, constrained to the fuel cost. To reduce the running cost, it is important to operate by managing new ships the design of which has been defined previously with the aim of reducing the fuel consumption and the running expenses. In general this choice requires a larger starting investment capital to define better hull lines and equipment on board with small consumption. Energy systems using renewable resources can be planned to be used on board for the ship propulsion or to supply local electrical plants or to be used for local equipment. The design of new engines for ship propulsion is a subject of long and important engine manufacturers and new proposals are launched on the market, as the new bi-fuel engines, operating with fuel oil during the navigation and gases in harbor calls and in coastal navigation. This problem can be important to reduce the pollution in closed waters, like the upper Adriatic Sea.
