IMO Takes First Steps to Decarbonise Shipping

Consider the humble washing machine – whether it’s on a ship or in your home, it will have an energy rating. Newer, more modern machines are rated at A and above whereas less-efficient older machines may be rated at F. So, when it comes to the time for replacing your washing machine after several years of use, it’s likely you will look for one which is more efficient and cheaper to run than your last.

But what if you needed to reduce the carbon footprint of your machine before being able (or afford) to buy another? Following the recent announcement by the IMO on some of the measures to reach its objectives on reducing GHG emissions, this is what will be asked of shipowners and operators.

We look at two of IMO’s proposed methods to achieve a carbon intensity reduction in the short-term. But first, a reminder on IMO’s strategy.

IMO goals on GHG emissions – a reminder

In simple terms:

By 2030: reduce CO2 emissions per unit of ‘transport-work’, as an average across international shipping, by at least 40% (compared to 2008 levels).

By 2050: reduce CO2 emissions per unit of ‘transport-work’, as an average across international shipping, by at least 70% (compared to 2008 levels).

By 2050: reduce the total annual GHG emissions by at least 50% (compared to 2008 levels).

The 2030 target should be partly achieved through finding operational efficiencies, such as speed reduction and voyage optimisation. Any remainder may need to be met by vessel modifications and changing to lower-carbon fuels.

New short-term regulatory measures

Draft new mandatory measures have been agreed by the IMO working group in a bid to reduce greenhouse gases (GHG) from shipping and will be put forward for formal adoption at the MEPC 76 session, to be held during 2021. The amendments to Marpol Annex VI will be circulated among IMO member states with a view to entering into force by 2023.

The proposed amendments to the MARPOL convention require a dual approach for ships to reduce their carbon intensity to meet the 40% reduction target by 2030, based on the technical and operational measures described below.

Efficiency Existing Ship Index (EEXI)

Existing ships of 400 GT and above will be required to calculate its attained Energy Efficiency Existing Ship Index (EEXI), which indicates its energy efficiency.  The vessel must then meet a specific required EEXI, which is based on a required reduction factor to reduce its carbon emissions.

The EEXI is a variant of the Energy Efficiency Design Index (EEDI), which applies to new ships built after 2013 and where the requirements become increasingly stringent over time. The EEDI measures the theoretical CO₂ emissions performance based on engine design and performance data to promote the use of more efficient (and less polluting) engines. It allows for different types and sizes of vessels by using a capacity per mile rating (e.g. grams CO₂ per tonne mile). The smaller the EEDI, the better!

The implementation and enforcement of EEXI will broadly follow that of EEDI, including survey and certification. It is expected that vessels must meet the required EEXI by the first intermediate renewal survey after the 2023 enforcement date.

It is expected that most existing ships will meet the required EEXI by limiting engine or shaft power or by installing energy saving devices. However, a recent paper by the International Council on Clean Transportation (ICCT) has raised doubts on the effectiveness of the EEXI measure as many vessels are already operating at reduced power through slow steaming.

Owners of vessels that will fall under the EEXI regulation may want to consider investigating early the impact of this requirement and if and how it can be met.

Carbon Intensity Indicator (CII)

The CII is an operational measure proposed for ships of 5,000 GT and above, which aligns with the requirements on recording vessel fuel consumption in accordance with the IMO Data Collection System (IMO-DCS).

The proposal will require each applicable vessel to have determined its annual operational carbon intensity indicator. The annual reduction factor needed to improve the ship’s operational CII within a specified rating level is then determined.

The ship’s actual (achieved) CII is compared with the required annual operational CII and the result is a carbon intensity rating from A (major superior) to E (inferior).

The performance level will be recorded in the Ship’s Energy Efficiency Management Plan (SEEMP). The SEEMP will be audited using the principles of the ISM code.

It is expected that a ship rated at D for three consecutive years, or E for one year, will be required to submit a corrective action plan, to show how an improvement to meet the required index (C or above) will be achieved.

Port Authorities, Administrations and other relevant stakeholders are being encouraged to provide incentives to vessels rated A or B.

Concerns have been raised by some in the industry on how the CII does not properly consider the effect of external factors on a vessel’s operational efficiency. If your ships sail mostly in adverse weather conditions will this compare poorly against vessels that operate in mostly calm tropical waters? Or if the vessel needs a surge of power for safety of navigation how will this be recorded and offset?

Therefore, a phased implementation of CII has been agreed where the CII calculations are reassessed after three years.

Find out more:

See here for Decarbonisation shipping advice.

Read more of our articles on setting a course to zero emissions in Signals edition 118 here.

Learn more about the resurgence of wind power as a solution here.

The International Chamber of Shipping (ICS) publication ‘Catalysing the Fourth propulsion Revolution’.