Optimising the anti fouling process

A new white paper by UK vessel performance optimisation software developer, GreenSteam, reveals that cleaning the vessel’s hull before it reaches a critical level of 10% fouling will result in fuel savings of around 40%.

The paper suggests taking a “proactive, condition-based strategy” to hull cleaning management using advanced analytics. It advises harnessing a predictive strategy using machine learning software, historical and live data that can be used to create a vessel performance model that is combined with environmental factors to build up a complete picture of hull fouling.

Cost benefits

The company’s studies showed that relying on periodic, scheduled hull cleaning is a costly approach for operators because the rate of fouling varied widely. Similarly, leaving fouling assessments to inspections is flawed because it provides only a snapshot in time and is reliant on the competence of the inspector.

Rather than rely on these methods, GreenSteam has created a machine learning platform with SMART push notifications that allow vessel operators to optimise hull cleaning by setting limits which trigger automatic alerts when thresholds – such as the 10% marker when fouling moves from simple slime growth to the more serious issue of firmly bonded marine organisms.

GreenSteam has also identified a further three rules to optimise hull cleaning, these being increasing vigilance if the rate of fouling exceeds 10% per year, cleaning the hull when the accumulated cost of wasted fuel from fouling matches the cost to clean the hull and cleaning the hull before the daily excess fuel consumption exceeds the party speed/consumption plus a 5% allowance.

According to their research, applying this strategy across the industry could result in a wide net payback of $1.0bn/year alongside an annual 40m MT reduction in CO2 emissions.

Hull fouling is the most significant preventable factor leading to fuel waste. The growth of organisms on a vessel hull increases the resistance to motion and when left unchecked, can increase fuel costs by over 20%, which in turn results in higher emissions.

When fouling passes a certain point on its growth trajectory, it becomes exponentially harder to clean without damaging the coating. This can result in further issues down the line, leading to poor performances alongside extensive and cost-prohibitive periods of dry docking in ports.