Analysis of the energy efficiency design index for two container ships and EEDI influence on propulsion performances

As a technical measure to control CO2 emissions from ships, the International Maritime Organization (IMO) has developed the Energy Efficiency Design Index (EEDI). IMO takes into consideration the technical development of all the components that influence CO2 emissions, to achieve a minimum level of energy efficiency per capacity mile for new ships. The paper is focused on Energy Efficiency Design Index calculation for two container ships: 800 TEU and 1805 TEU and analysis of EEDI requirements influence on propulsion performances. Ships propulsion systems have been designed: three main engines have been selected for each ship and the propellers have been redesigned to consume delivered power. To achieve an EEDI within standards, a balance of performances is needed between: ship capacity, power, speed, minimum fuel consumption and the smallest amount of gas emitted into the atmosphere.