The environment protection is one of the main concerns of our society and this paper aims at presenting some of the international efforts in the maritime transport. Marine pollution consists of water pollution and also air pollution. Regardless of the delay in recognizing the latter type of pollution, it rapidly gains many organizations to argue on it. The first step was including a dedicated annex in the International Convention for the Prevention of Pollution from Ships, which seek to minimize the airborne emissions from ships. The efforts continued and the International Maritime Organization has developed a series of measures for monitoring the emissions. These are grouped in three main directions: technical, operational and management related. The subject of our study is the concept of Energy Efficiency Operational Index, developed to provide ship-owners and ship-operators with assistance in the process of establishing a mechanism to achieve the limitation or reduction of emissions from ships in operation. It serves as a monitoring tool and it represents the mass of CO2 emitted per unit of transport work. The paper presents the way how the commercial software can be used for estimating the EEOI value before the voyage, in comparison with the true value calculated on board. The true value is calculated based on unpredictable factors that might appear during the voyage: varying the speed, days on anchor, or waiting for orders period. The authors included these in a software solution, which allows to emphasize the influence of the on board measures over voyage energy efficiency. (C) 2014 Elsevier Ltd.
