Reduction of CO2 emissions is of paramount importance in the fight against climate change globally and the decarbonization of global shipping..
Thus far, there has not been a formal methodology for calculating, collecting, or recording data relating to the intensity of CO2 emissions from the various ships operating in our oceans..
As of the 1st of January 2023, it has become mandatory for all ships to initiate the collection of data for the reporting of their annual operational Carbon Intensity Indicator (CII) and CII rating along with the ships’ Energy Efficiency Existing Ship Index (EEXI) to measure the energy efficiency attained..
These initiatives came into force on the 1st of November 2022 as part of amendments to the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex VI..
These technical and operational amendments were developed under the framework of the Initial IMO Strategy on Reduction of GHG Emissions from Ships agreed in 2018 and require ships to improve their energy efficiency in the short term and thereby reduce their greenhouse gas emissions..
What is CII rating and how does it work..??
Carbon Intensity Indicator (CII) basically measures/calculates the efficiency of a ship in transporting cargo or passengers in terms of its CO2 emissions per nautical mile and carrying capacity.. CII determines the annual reduction factor needed to ensure continuous improvement of a ship’s operational carbon intensity within a specific rating level..
CII applies to all ships above 5,000 GT covering but not limited to container ships, bulk/gas carriers, tankers, multi-purpose/general cargo ships, reefer ships, combi carriers, LNG carriers, Ro-Ro ships, and cruise ships..
As per the guidelines set by the IMO, the carbon intensity of a ship will be rated as
- A – major superior
- B – minor superior
- C – moderate
- D – minor inferior; or
- E – inferior performance level
The performance level will be recorded in a “Statement of Compliance” to be further elaborated in the ship’s Ship Energy Efficiency Management Plan (SEEMP)..
As per IMO, a ship rated D for three consecutive years, or E for one year will have to submit a corrective action plan to show how the required index of C or above will be achieved..
Port state administrations, port authorities, and other stakeholders are also encouraged to provide incentives to ships rated as A or B..
While a ship can run on a low-carbon fuel clearly to get a higher rating than one running on fossil fuel, there are many things a ship can do to improve its rating using :
- hull cleaning to reduce drag;
- speed and routing optimization;
- installation of low-energy light bulbs; and
- installation of solar/wind auxiliary power for accommodation services.
As per DNV, CII is based directly on fuel consumption, which is influenced by how a specific ship is operated in combination with its technical efficiency and fuel.. The value of CII will be affected by the type of fuel used, the efficiency of the vessel, operational parameters such as vessel speed, cargo transported, weather conditions, and the general condition of the vessel including biofouling..
DNV suggests that shipowners can control the CII by optimizing operations and ensuring vessels are in a good condition.. Charterers also hold major sway over the CII of the ships as they charter ships based on speed as well..
Review of the EEXI and CII
The introduction of mandatory EEXI and CII comes under the framework of the Initial IMO Strategy for Reduction of GHG Emissions from Ships, adopted in 2018 which sets out candidate short- mid- and long-term measures..
The introduction of EEXI and CII measures falls under the Strategy’s short-term measures which commit the IMO to a target of reducing the carbon intensity of international shipping by 40% by 2030, compared to 2008..
In line with this, the IMO’s Marine Environment Protection Committee (MEPC) will review the effectiveness of the implementation of the CII and EEXI requirements by the 1st of January 2026 and adopt further amendments as required..