The International Maritime Organization (IMO) keeps an important role in field of safety, secure, and environment. The International Convention for the Prevention of Pollution from Ships, MARPOL 73/78 is an international convention that adopted by IMO. Its regulation forces all ships both design ships and operating ships that need to obey this convention along with the energy efficiency measure. In particular, the Energy Efficiency Design Index (EEDI) for new ships and the Energy Efficiency Operational Indicator (EEOI) for existing ships. The objective was studied the Energy Efficiency Operational Indicator, EEOI under impacting on navigation conditions such as weather condition, amount of cargo carried, distance traveled so on. This research was carried out by calculating the EEOI index for certain vessel, M/V NSU JUSTICE 250,000 DWT of VINIC shipping transportation company in Vietnam. In addition, the combination between the Taguchi method and Grey Relational Analysis (GRA) method was conducted to analyze and optimize the experimental data for M/V NSU JUSTICE 250,000 DWT in aim with improvement of the energy efficiency of ship. The collected-results will be the effective solution in the field of ship operation activities and ship management of ship owners as well as the fuel consumption reduction of engines and sea environmental protection from ships.

Keywords: Energy efficiency of ships, bulk carriers, Taguchi method, Grey Relation Analysis, EEOI, MARPOL 73/78.