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If the coating fits

The Naval Architect: February 2019

It’s not often that a paying customer is turned away in the world of business. However, the complexities and tight budgets found in maritime mean doing so is sometimes the best option, both for the customer and the company. A case in point is Jotun’s Hull Performance Solutions (HPS) offering – according to Global Concept Director Stein Kjølberg, “I have never in my career said no to more customers than with HPS…I say there’s no point investing that much more if you can get away without it.”


Kjølberg’s honesty may be refreshing, but he’s also realistic. The Hull Performance Solutions concept is based upon the application of advanced antifouling products, the performance of which is then measured by meticulous data collection and analysis, with the aim of delivering up to 15% in propulsion efficiency and resulting in 8.5% fuel cost and GHG emissions savings. Only vessels with a suitable operational profile – usually those of significant size, on long, regular deep-sea routes, such as containerships – are likely to see a benefit that surpasses the initial investment required. Besides operational profile, some vessels may be too close to the end of their lifespan, or not able to do a full paint blast, based on the time between drydockings.


When assessing a vessel’s suitability, Jotun looks at vessel speed, the average temperature of the seawater on the vessel’s routes, and the number of days active through the year. AIS data is also leveraged to account for actual operation, since the newbuilding spec isn’t always met in reality. This can be important in the case of seawater temperature, for instance, where if the spec cites 25°C, but trading is undertaken at 30°C, the antifouling will need to be different.


Less suitable vessels may still experience minor savings, but for Kjølberg, it is better to target vessels for which HPS is tailored. This is especially important given that Jotun include a high-performance guarantee, meaning the company will be liable to pay up to 60% back if HPS doesn’t deliver on contracted promises. With 900 references to date, though, Jotun has evidently identified a sizeable market segment that responds well to the concept; there has been only one performance-related payback so far, which Jotun attributes to a failure to apply enough paint to the newbuild vessel following a spec change (although it paid out nonetheless).


Data collection
The foundation of HPS, as mentioned, is data collection. Vessels must first be equipped with (or utilise existing) sensors, including a Doppler log, torque meter, draft meter, and anemometer, which are integrated with the vessel’s GPS and a data-logging unit. High-frequency data is then collected on an almost constant basis – every 15 seconds – and combined with traditional vessel noon reports through in-house data analysis at Jotun to “give a good assessment of performance,” says Kjølberg. This performance regards fuel savings delivered by the antifouling as it cancels out speed loss, and the change in antifouling efficacy over time (and, by extension, the benefits delivered at drydock as the hull is re-coated).


“The high frequency data can tell you exactly what is happening, and the noon data is more like trends,” Kjølberg advises. “The difference is between the accuracy – if you use high frequency data, you have plus/minus 0.3% points, whereas for noon data it can be anything from 4 to 5%.” Some owners are unwilling to invest in sensor equipment to collect high-frequency data, he claims, saying they are happy with the insights provided by noon reports. However, charterers may see a differnet side, Kjølberg notes: “If the charterer can accept plus or minus 5%, that’s fine, but owners can make their vessels a lot more attractive to them [using high-frequency data].”


With such a rich data set to draw from, owners can gain useful insights unrelated to the application of antifouling – something that Jotun encourages, as it allows HPS to deliver added value. Kjølberg relates an example where the data proved to be especially beneficial: “The vessel left the yard after [having antifouling] applied, at 65rpm, which is normal trade. Then they dropped down to 59 because of slow steaming, and they were doing turbocharger cleanings because the speed is too low and they needed to blow off some of the soot. They went back to 65rpm, and they couldn’t understand why fuel consumption was sky high. It was because they continued the same process – every single day they did turbocharger cleanings. They couldn’t pick it up because they were just using noon reports; you just see that operation is average, but fuel goes up. If you look at high-frequency data, you can see all the peaks. We told them that they could save US$85,000 a year just changing that kind of policy.”


Fleet-wide contracts
Over the seven years that HPS has been offered, Jotun has been building up a reference data bank, making it possible to show shipowners the kind of benefits they could expect based on vessels with similar operating profiles. Once these benefits are verified on one vessel, Kjølberg says that shipowners then look to opt for HPS across their fleet, which aligns with Jotun’s strategy for the concept: “Our success rate is measured by the same company re-purchasing, not just on the same vessel next time, but also throughout the fleet.” Signing up newbuilds is especially desirable – at present, they make up about 30% of business, but Kjølberg says “now we see the newbuilds picking up again and anticipate more contracts,” with owners specifying HPS to yards from the beginning of the contracting process.


With the growth of biocide-free paints developed in anticipation of possible future restrictions on copper use, and biomimetic coatings, Jotun’s successful run with HPS may stall in the future as the market seeks alternatives to conventional antifouling paints. However, sweeping regulations aside, as long as HPS continues to deliver significant savings for vessels in the segments for which it is tailored, it will remain popular as rising fuel prices and the cost of ballast water systems and scrubbers puts margins under pressure.