Energy Efficiency Design Index

Energy Efficiency Design Index — design-phase efficiency index in grams of CO2 per cargo-tonne nautical mile, required for newbuilds under MARPOL Annex VI Reg. 22 and MEPC.308(73). EEDI tightens in successive phases by ship type: Phase 0 (2013–2014) baseline, Phase 1 (10% improvement), Phase 2 (20%), Phase 3 (30–50% depending on ship type). Compliance is verified at the design stage and confirmed by a sea trial. EEDI applies to large new-builds (cargo and certain passenger ship types); the EEXI applies the equivalent retroactive standard to existing ships.