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Supporting Compliance to the Cruise Industry for the IMO’s EEXI and CII measures with minimal capital investment.

Number One Challenge For The Cruise Industry

As we enter 2022, it is all about reducing carbon! The countdown timer has begun for owners and operators to meet two new mandatory measures.  These are the Energy Efficiency Existing Ship Index (EEXI)  and Carbon Intensity Indicator (CII). Adopted by the International Maritime Organization (IMO) in June 2021. Existing cruise ships, including those using diesel-electric engines, must get ready to comply with the EEXI[i] and CII annual reporting and certification requirements being introduced 1 January 2023, with first ratings required by 2024.

Decarbonization has been a hot topic and, arguably, the number one challenge the marine industry faces for several years. In 2018, the IMO introduced the Greenhouse Gas Strategy. The goal was to achieve net-zero carbon emissions and a 70% carbon intensity reduction by 2050. By 2026 it is to reduce carbon intensity by 11% compared to 2019. And for 2050, by 70% compared to 2008. The EEXI and CII are short-term strategies for meeting these pollution-prevention goals. There are no crystal balls in science, stock-taking along the route to 2050 is the initial GHG strategy. With submissions of proposals on how to progress set for 2023. By 1 January 2026, a hard look at the effectiveness of the EEXI and CII requirements.

What are the EEXI and CII?

They are two aspects indicating the energy efficiency of any given ship above 5,000 gross tonnages. The EEXI is a technical index. Using a technical formula to estimate a ship’s design (how the ship is equipped and retrofitted) for efficiency in reducing its carbon emissions. The CII is an operational index of the same ship’s in-service (real world) efficiency in moving cargo (or, for cruise ships, passengers).

Furthermore, this measures the actual fuel consumption (and, therefore, corresponding GHG emissions) for distance traveled. CI ratings range from A to E: A to B = high (and possibly incentivized) ratings, C = minimum rating required, D to E = ship needs to (a) submit a corrective action plan, (b) show substantial improvement across the next three consecutive years, and (c) meet required index (C or above) within three years. Air pollution or energy efficiency certificate is awarded to ships receiving ratings of A-C. Ships will be surveyed and rated annually by their respective classification societies.

The figure below describes the process and responsible parties for attaining IEE certification.[ii]


What is the Cruise Industry Doing?

The Cruise Line International Association (CLIA) is now three years into its members’ commitment.  The goal is to reduce the rate of carbon emissions by up to 40% across the cruise industry’s global fleet by 2030. Illustrating this commitment is the CLIA’s completion of an Environmental Technologies and Practices (ETP) inventory in 2021, covering 242 oceangoing ships.[iii]  A fundamental approach to preparing for 2023 was retrofitting vessels currently in operation to replace or improve existing technologies and operational practices. These mostly focused on energy-saving by limiting or optimizing engine power and by optimizing speed performance. This lines up with a quote on the Wärtsillä (who position themselves as a global leader in technologies and lifecycle solutions for the marine and energy industries) website that there are essentially two options to increasing fuel efficiency and reducing carbon emissions:

“Either you reduce the vessel’s power and therefore you lose speed, or you improve the hydrodynamics of the vessel, so you use less power to maintain the same speed.”

In our reading, it appears that cruise industry owners/operators’ go-to decarbonizing strategy is the use of ecological, non-toxic, slick hull paint coatings, apparently improving fuel efficiency by five percent. However,  there are other ways to increase energy efficiency and reduce carbon emissions. For example, a way to prevent hull corrosion is using an impressed current cathodic protection (ICCP) system—galvanic anodes are generally shaped and fitted flush to the hull to minimize drag in the water.

Another way is to take a comprehensive approach to protect ships’ internal seawater systems. As well as other niche areas from biofouling by using a marine growth protection system (MGPS). Internal seawater systems use pumps to deliver seawater, sucked into and collected in one or more sea chests, through a series of pipes to various onboard locations such as heat exchangers, box coolers and chillers; ballast tanks; exhaust scrubber systems; firefighting systems; freshwater makers, air conditioning and refrigeration. Oddly, although understandable, protecting internal seawater systems from biofouling is overshadowed by the attention given to hull protection. This is largely because external biofouling is more accessible than is within a ship’s internal seawater systems.[iv]

Additional Solution

Biofouling of ships’ internal seawater systems has structural and operational impacts. For example, biofouling increases the surface roughness of pipes and equipment and restricts water flow. Interestingly and importantly, biofouling can also set up and exacerbate corrosion—known as “microbiologically influenced corrosion”—and subsequent perforation and leakage. Impairment of internal seawater systems leads to operational inefficiencies or outright failures. Operational inefficiencies in the use of seawater for engine temperature control by cooling or heat-exchange systems will affect a ship’s fuel efficiency and performance.iv

Not only this, but biofouling of ship’s internal seawater systems and niche areas or carried onboard in drums after in-service cleaning, adds a lot of wet weight to a ship. One first-hand example is a photo we have of a ship carrying fifty forty-gallon drums of removed biofouling. No matter the location, added wet weight from biofouling will increase drag and, therefore, even slowing down will burn fuel and not reduce emissions.

Therefore, an MGPS system is a cost-effective method of antifouling and microbiologically influenced corrosion protection.

Way Forward

MARELCO™ suite of innovative antifouling and anticorrosion solutions supports the cruise industry with minimal capital investment, in getting ready for and meeting the IMO’s EEXI and CII measures that are mandated and in the works for 2023.

The cruise industry comprises less than 1% of the global maritime community.  However,  governing bodies and climate activists keenly observe and scrutinize their impact on our world’s climate and oceans. Consequently, the cruise industry is paying attention to the Green House Gas Strategy.  Equally in decarbonization and other measures (such as the reduction or elimination of single-use of plastics onboard). EMCS Ltd. is keen and ready to partner with the cruise industry in a vessel-by-vessel way to support their bid to contribute to the global decarbonization effort by using a mix of solutions that includes those of antifouling and anticorrosion.

[i] The Energy Efficiency Design Index (EEDI) is the measure for new builds.


[iii] At the same time, the CLIA also completed ETP inventories for 62 new builds than on order.

[iv] Davidson, i., Cahill, P., Hinz, A., Kluza, D., Scianni, C., & Georgiades, E. (2021). A review of biofouling of ships’ internal seawater systems. Frontiers in Marine Science, 8, doi: 10.3389/fmars.2021.761531




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