Energy Efficiency Existing Ship Index
Abbreviation: EEXI
One-off retroactive efficiency index applied to ships built before EEDI; effective 2023.
In practice
One-off retroactive index applied at the first 2023 IAPP renewal survey. Many ships installed Engine Power Limitation; class verifies the EPL setting at intermediate surveys.
Regulatory detail & full definition
Energy Efficiency Existing Ship Index — one-off retroactive efficiency index applied to existing ships of 400 GT and above under MARPOL Annex VI Reg. 23 and MEPC.350(78), effective 2023. EEXI parallels EEDI but is computed from the ship's current particulars rather than design submissions. Many ships meet EEXI by Engine Power Limitation (EPL) — a class-approved override that caps maximum continuous rating below the engine's rated power. EEXI is a one-time check; ongoing operational efficiency continues to be measured and rated annually through CII.
Authoritative source: MARPOL Annex VI (Air pollution) ↗
Related
Source: MARPOL Annex VI Reg. 23; MEPC.350(78)
High confidence
Editorial confidence: how we grade.