In order to improve energy efficiency for ships International Maritime Organization (IMO) introduced Energy Efficiency Design Index (EEDI). For every new ship the attained EEDI has to be calculated and not higher than the required EEDI which is calculated from the reference line value and appropriate reduction factor. The reference line value represents the world fleet average and is dependent on the ship type and size. The reduction factor represents a reduction for the EEDI relative to the reference line value and is increased in a set of time intervals. However, the scheme of the reduction factor change seems to be rigidly set and could lead to design issues and ship under powering. This study estimates the CO2 emission from bulk carriers based on the current reduction factor change policy. Other policies and some innovative approaches are also discussed and the CO2 emission in every scenario is estimated. The results are then compared with the requirement of reaching mean global CO2 stabilization level of 550 ppm in the atmosphere. It is concluded that policies which include feedback from the shipbuilding sector impose requirements that could be much easier to satisfy and which will lead to overall lower CO2 emission. (C) 2015 Elsevier Ltd. All rights reserved.