An exciting new model for sustainable hull performance
Philippos Sfiris, Head of Market Strategy and Vessel Performance, GIT Coatings looks at a new model for sustainable hull performance with the results obtained after a gas carrier completes a full year under a graphene coating and robotic grooming regime.
In an industry long dominated by biocidal antifoulings and reactive cleaning, a different model of hull maintenance is beginning to emerge, and for the first time, it now has a full year of real-world proof. Over the past 12 months, a gas carrier has operated with a graphene-based foul-release coating on its hull, paired with an onboard grooming robot operated by the crew during idle periods.
The combination is straightforward yet disruptive: the graphene coating provides an ultra-smooth yet hard surface engineered for frequent light cleaning, while robotic grooming removes early-stage slime before it develops into more persistent forms of fouling. This keeps the hull consistently close to ‘as-docked’ condition without biocide release, without abrasive cleaning and without depending on uncertain port permissions for reactive cleanings.
This is the first documented case globally of such a system being used continuously in commercial operation for a full year. And it worked – not in controlled trials, but under the unpredictability of global trade.
A tailored plan before the vessel even left dry dock
From the outset, the approach was not simply ‘apply the coating and hope for the best’. Before the vessel sailed, a ship-specific proactive cleaning (or grooming) plan was developed based on its trading pattern and fouling-risk profile. High-risk regions, frequent idle periods and the vessel’s speed profile indicated that slime could accumulate quickly if not managed early. Instead of waiting for visible fouling or performance drop, the plan defined when inspections would take place, how often grooming would be needed and in which ports or anchorages cleaning was realistically feasible considering local restrictions and time availability.
It was a strategic, data-informed framework intended to make proactive cleaning achievable – not a theoretical schedule detached from real operations, with the aim of achieving sustainable hull performance.
A year of real-world sustainable hull performance operation
Across the first 12 months, the vessel completed seven underwater inspections and three grooming events. As expected in commercial trade, the year included tight port schedules causing partial or delayed cleanings, early robot reliability issues, unexpected idle periods and regulatory constraints on where cleaning was allowed.
Despite these conditions, each grooming restored the hull to clean condition with no damage to the coating, and no hard fouling developed at any point. The graphene coating showed no measurable degradation, maintaining the smoothness required for efficient operations and trouble-free grooming.
Better performance results
Year One results were clear and verifiable: approximately 6% power improvement out of dry dock compared to the premium antifouling previously used, under similar trading conditions; less than ~2% added power across the entire first year, despite more than 180 idle days; 3–5% efficiency regained after each grooming as early-stage slime was removed. Taken as a whole, the vessel’s fuel consumption for the year using the graphene-coating and grooming combination was lower than with the conventional premium antifouling for the same period, even though execution of the grooming plan was far from perfect.
Lower emissions, no biocide release
Because the graphene coating contains no biocides, no toxic substances entered the marine environment, as grooming did not require aggressive scrubbing. Maintaining a consistently clean hull also reduced fuel burn, directly lowering CO₂ and air emissions.
The vessel delivered both sides of the sustainability equation: cleaner oceans and lower carbon output.
What the industry can take from this
- It can be done.
A full year in operation has now shown that a graphene-based foul-release coating combined with light, frequent robotic grooming can maintain a clean hull – continuously, predictably and without biocide release.
- It performs better.
Across the year, the vessel consumed less fuel than during the equivalent period on a premium conventional coating under similar trade conditions. Performance remained close to ‘as-docked’ levels despite significant idle time, and light grooming consistently restored efficiency without damaging the coating.
- It requires a system, not just a coating.
Perhaps the clearest lesson is that success came from a structured in-service support model, not from coating chemistry alone. The vessel operated under a tailored grooming plan built around its actual trade, followed by continuous visibility of hull condition through inspections, performance analysis and monthly reviews involving both the ship operator, the coating maker and the robot supplier. This ongoing feedback loop enabled timely adjustments – an essential element of making proactive hull management work in real operations.
- There is still room to optimise.
The first year also highlighted where the industry can improve the model further: broader port coverage and approved service partners to complement onboard robots and addressing niche areas robots cannot reach; remote robot operation, reducing crew involvement and improving cleaning consistency across voyages. These refinements would narrow the gap between real-world execution and the theoretical optimum, unlocking additional efficiency gains and simplifying adoption for more vessels to improve sustainable hull performance.
A working blueprint for the future
What makes this case compelling is that it survived the real world: operational challenges, port restrictions and all the unpredictability that defines global shipping. The vessel still maintained a clean hull, avoided hard fouling, preserved coating integrity, and delivered year-long efficiency gains – without releasing biocides and without fuel penalties over time.
For an industry seeking solutions that reduce both emissions and environmental harm, this is proof that a new, sustainable sustainable hull performance category of hull management has matured to the point of practical application and that it already works in everyday commercial operation.
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