Energy Efficiency Existing Ship Index, a measure introduced by the IMO to reduce the carbon intensity of existing ships by requiring them to meet a minimum energy efficiency standard. Ships that do not meet the required EEXI must implement technical measures such as engine power limitation, hull modifications, or energy-saving devices.
Also known as: Energy Efficiency Existing Ship Index.
Category: Marine Engineering
On The Maritime
The desks where this concept is measured.
In the Glossary
Energy Efficiency Existing Ship IndexEEXI
A one-time IMO design-efficiency standard that existing ships must meet, the in-service counterpart of the EEDI for new ships.
Read the full explanation in the GlossaryRelated terms
More in Marine Engineering
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Back to DictionaryEntry updated May 2026