Maritime shipping is under increasing pressure to measurably reduce its CO₂ emissions. With the Energy Efficiency Existing Ship Index (EEXI) and the operational efficiency rating CII – often referred to as „UEFI“ in German – the IMO has created globally applicable framework conditions. At the same time, two further sets of regulations are coming into force in the EU with emissions trading (EU ETS) and FuelEU Maritime, which will gradually become mandatory from 2024 and 2025 respectively.
What is behind EEXI and „UEFI“?
EEXI – the technical efficiency check
EEXI assesses whether the design of an existing ship – including engine power, speed and capacity – meets a defined efficiency standard. The rule applies to seagoing ships of 400 GT or more and must be verified once per ship, usually in the course of a periodic survey.
Typical measures for complying with EEXI:
Engine Power Limitation (EPL)
Propeller and hull optimisation
exhaust gas aftertreatment
reduction in service speed
UEFI (CII) – the operational efficiency rating
The CII assesses the actual carbon intensity of a ship annually based on the cargo transported and the distance travelled. It applies to ships of 5,000 GT or more engaged in international traffic.
The annual rating is based on a scale from A to E. Anyone who receives a D three times in a row or an E once must submit a corrective action plan and will be monitored more closely.
Typical operational levers:
Manage speed and routes in a targeted manner
Optimise port stays
Improve utilisation
Weather routing and energy management
FuelEU Maritime & EU ETS – the EU requirements
FuelEU Maritime
Since 2025, limits have been in place in EU waters for the greenhouse gas intensity of the energy used. Compliance can be achieved, for example, through alternative fuels, shore power (OPS) or pooling.
EU Emissions Trading Scheme
EU emissions trading has applied to large ships since 2024. Companies must have their emissions verified annually and submit emissions allowances (EUAs). The amount to be submitted will increase to 100 % by 2027.
How the regulations interact
EEXIEnsure minimum technical standards
UEFI/CIIEnsuring operational efficiency in everyday life
FuelEU: Promoting low-carbon energy at sea
EU Emissions Trading Scheme: Assigning costs to emissions
The goal: a combined system of design, operation, energy and market incentives.
Catalogue of measures for practice and planning
Technical measures (EEXI)
Engine Power Limitation (EPL/ShaPoLi)
Propeller jets, hull coating, hull cleaning
Waste heat utilisation and economical on-board technology
Drive more slowly across the board → may worsen CII
Underestimating MRV data quality → ETS risks
Planning FuelEU too late → Fuel shortage looms
Contracts without climate clauses → Risks associated with choosing the wrong partner
FAQ
What is the difference between EEXI and UEFI (CII)?
EEXI assesses the technical efficiency of an existing ship as a one-off compliance measure. UEFI/CII assesses annual operational efficiency and assigns an A–E rating.
Does UEFI/CII apply to all ships?
No, only for ships of 5,000 GT or more engaged in international traffic. Smaller vessels are exempt.
How does the EU ETS affect my costs?
Emissions related to the EU must be covered by certificates. The costs depend on the amount of emissions, the proportion of the route and the market price.
What exactly is FuelEU Maritime calling for?
A decreasing limit value for GHG intensity. Achievable through alternative fuels, shore power and/or pooling.
How often is my CII rating determined?
Once a year. Poor ratings lead to corrective plans and increased monitoring.
Conclusion
EEXI (design) and UEFI/CII (operation) form the international framework. FuelEU Maritime and EU ETS are creating additional pressure to act in Europe. Those who invest today will reap long-term benefits: stable ratings, avoided penalties and genuine competitive advantages.
For an individual assessment of your fleet and trades, we recommend a personalised quote.
Disclaimer: All information in this article has been carefully researched but is subject to change at any time. ODS Orient accepts no liability for the topicality, accuracy and completeness of the information provided.
Do you have any questions or would you like to make use of our RoRo service?
The IMO CO2 fee for shipping is to take effect worldwide from 2028. However, the strategic, contractual and operational decisions will already be made in 2026 and shipping companies, shippers and logistics service providers will have to adapt their fleets, routes, charter contracts and reporting processes at an early stage. Those who do not react until 2028 risk higher cost pressure, capacity bottlenecks and contractual risks. Scenario planning, documentation security and sustainable transport strategies are crucial now. Short answer in 5 bullet points [...]
FuelEU Maritime obliges shipping companies to gradually reduce the greenhouse gas intensity of marine fuels from 2026. For the RoRo sector, this means new surcharge models, more complex timetable planning and stricter documentation requirements. The main keyword fueleu maritime roro is therefore becoming a central issue for shippers, charterers and shipping companies. Those who can reliably maintain ETD and ETA and efficiently manage POL and POD [...]
