There has been substantial progress in the marine engine technology, which is the result of industrial efforts to meet specific demands for each type of vessel’s operational features. In particular, there have been efforts to decrease vessel operating costs through the reduction of fuel oil. In addition, growing voices demanding efficient and eco-friendly vessel operation has led the industry to keep the practice of slow steaming to guarantee economical sailing. Against this background, the IMO MEPC adopted the EEDI to regulate the levels of CO₂emission from shipping.
However, there was the growing concern that the safety of ship may be jeopardized by the industrial efforts to meet the EEDI’s regulation in a way toward slow steaming and reduction of engine propulsion power. Facing this concern, there have been debates and studies regarding how to determine the levels of the minimum propulsion power. Against this background, the MEPC’s 65th session held in May 2013 adopted the “2013 Interim Guidelines for Determining Minimum Propulsion Power to Maintain the Manoeuvrability of Ships in Adverse Conditions.”
After evaluating the empirical validity of the MEPC’s guidelines by analyzing available data of the engine propulsion power, this research suggests an alternative guideline on how to determine the minimum propulsion level. Based upon the results of the statistical analysis, this study also suggests a guideline on how to determine the minimum propulsion power of a ship under the DWT 20,000T size, which is not regulated by the MEPC’s current guidelines. In addition, the present research reviews the current trend of the MEPC’s approaches toward how to set the minimum propulsion power. It also confirms the importance of guaranteeing minimum propulsion power by examining marine accidents caused by reduced propulsion power and by conducting a survey of seafarers.
This author acknowledges that the evaluation formula introduced in the statistical analysis of this study did not consider physical features of each ship examined in the analysis. Despite this methodological limit, this author emphasizes that the present research evaluates available data of the propulsions power according to the level 1 evaluation guideline of the MEPC and that it suggests an alternative guideline on how to set the minimum propulsion power. This author believes that the suggested simple linear function will arguably help to determine the proper level of propulsion power according to the size of each ship. This study will arguably contribute to establishing navigation safety by provoking a future study on the navigation safety and main engine propulsion power.