In the vast, interconnected world of global shipping, a silent, often overlooked culprit is quietly chipping away at operational efficiency and environmental goals: hull fouling. A recent study, published in the journal ‘Applied Ocean Research’ (translated from the original title ‘Applied Ocean Research’), has shed light on the underestimated penalty of hull fouling, revealing a significant impact on fuel consumption and greenhouse gas (GHG) emissions.
Led by Youngrong Kim from the School of Civil and Environmental Engineering at Nanyang Technological University in Singapore, the research team conducted a scenario-based analysis on a staggering 52,636 vessels across six major ship types. By integrating Granville’s similarity law for added resistance with dynamic fouling growth models and vessel-specific operational profiles, they estimated the emission penalties for the global fleet.
The findings are eye-opening. Moderate fouling can increase annual fuel consumption and GHG emissions by an average of 20–30%. “This is a substantial figure,” Kim notes, “especially when you consider the scale of global shipping operations.” Large container ships, tankers, and bulk carriers emerged as ‘global hotspots’, accounting for the majority of these emissions. For instance, a single large container ship with a capacity over 15,000 TEU can emit as much as 20,000 tons of additional CO2 annually due to hull fouling.
So, what does this mean for the maritime industry? Firstly, it underscores the importance of proactive hull management. As Kim puts it, “Proactive hull management is a fundamental lever for enhancing ship hydrodynamic performance and, consequently, a highly effective and immediate decarbonization measure.” This presents a significant opportunity for ship operators to improve their environmental performance and reduce operational costs.
Moreover, the study highlights the need for a shift in focus. Often, the emphasis is on direct maintenance costs and off-hire periods, or on other energy-saving devices. However, this research shows that quantifying and addressing the performance loss from hull condition itself can yield substantial benefits.
In the broader context, this study provides a compelling case for the maritime industry to prioritize hull fouling management. It’s not just about keeping ships clean; it’s about making a tangible difference in the fight against climate change and improving operational efficiency. As the industry continues to grapple with decarbonization targets, this research offers a clear, actionable path forward.