The CO2 emission index used to evaluate the vessel design. The index compares theoretical CO2 emissions and transport work of a vessel (gCO2 /tnm). The goal is to design future ships with a design index to be stepwise reduced in the period from 2012 to 2018 to a maximum level of possibly 70% compared with the 100% design index valid for average currently designed ships. In August 2009, IMO has published guidelines on the calculation and verification of the EEDI.
Further reading: MEPC.1/Cir.681 and 682