CII: Carbon Intensity Indicator

In June 2021, the IMO adopted extensive new CO2 regulations applicable to all ships, including the Carbon Intensity Indicator (CII) rating scheme addressing operational efficiency. The CII requirements will take effect for all cargo, RoPax and cruise vessels above 5000GT and trading internationally.

Under CII ships are rated from A - E with A being the most efficient

Corrective plan required

IMO goals aim to cut shipping’s GHG emissions in half at least by 2050 compared to 2008, and achieve zero emmissions within this century

CII is calculated for each ship, not an entire fleet

Shipping’s share of total global CO2 emissions in 2018 was 2.89%

CII was adopted at MEPC 76 in 2021. Further guidelines will be decided at MEPC 78 in 2022

The CII is a measure of transport efficiency, calculated by:


For cruise & RoPax capacity is GT, for other ships capacity is DWT. For passenger ships, fuel used in port is included in the calculation

CII optimum speed

Operating too far from its optimum speed will have negative effect on a cruise ship’s CII

Foreship’s CII process

  • 1. Calculate CII for the ship and itinenary
  • 2. See how the ship complies with (planned) CII limits and define the target together with the Owner
  • 3. Prepare a plan how to meet the targets now and in the future:
    • Are itinerary changes possible? (speed, port calls, etc.)
    • Can ships be swapped between itineraries? (more energy efficient ships on more demanding routes, less energy efficient ships on less demanding routes)
    • What energy efficiency steps can be taken? (hydrodynamics, batteries, hotel load, etc.)
    • Could shore power have an effect?
    • Is a drop in fuel an option (bio-diesel, HVO) or converting the ship into another fuel (LNG, methanol, ammonia)?

The CII is based on reduction on 2019 reference level, with 5% reduction by 2023, then 2% annual reduction until 2026

People in the Foreship CII, EEDI & EEXI team
Foreship CII projects
EEXI = one time design certification
CII = emissions in operation