HomeCalculatorsEEXI Attained - Energy Efficiency Existing Ship Index

EEXI Attained - Energy Efficiency Existing Ship Index

Existing-ship EEDI variant. Same formula; reference speed is derived at 75 % MCR of the limited (EPL or ShaPoLi) engine power.

IMODesignMEPC.328(76)

Main engines (after limitation)

Power at 75 % of the LIMITED MCR, not the nameplate MCR.

Auxiliary engines

Attained EEXI
3.100gCO₂ / t·nm
Required EEXI
3.486gCO₂ / t·nm
Type-specific Z from MEPC.328(76).
Margin
11.1%
11.1 % below required - compliant.
Formula, assumptions, and limits
EEXI_attained = (Σ P_ME Cf SFC + P_AE Cf_AE SFC_AE) / (Capacity × V_ref_limited)
EEXI_required = Reference × (1 − Z_EEXI)  (20 % typical, 5–30 % by type)

EEXI re-applies the EEDI formula to existing ships. To comply without a capital retrofit, many operators cap the main engine via EPL or ShaPoLi - this lowers V_ref (and thus the denominator), which tightens Attained EEXI. Required EEXI is the same reference line minus a type-specific Z (20 % for most, 30 % for LNG and cruise, 5 % for small ro-ro and ro-pax).