Assessing the influence of the global emissions reduction targets on the design and performances of a ship’s propulsion system

Abstract

The paper presents aspects related the influence of the global gases emissions reduction targets on the design and performances of a propulsion system for a bulk carrier. In a first stage, the key elements of the ship propulsion system: main engine and propeller have been  chosen and designed. The aim was to obtain the maximum propulsive efficiency at the owner desired speed. Different combinations: diesel engine-optimal propeller have been designed and analysed from the efficiency point of view. In a second stage, considering the mandatory IMO regulations concerning CO2 emissions, the EEDI (Energy Efficiency De sign Index) has been computed for every designed case. To compliance EEDI targets, it was been necessary to reduce the ship speed, and a new propulsion system with lower speed performances has been designed. In this study, ship hull shapes were given and EEDI be came an important and critical factor in the design of the ship propulsion system. Other potential pathways to achieve emissions reduction targets will need to be identify in a future study.