Biofouling — the accumulation of barnacles, plants, and algae on ship hulls — is only getting worse as waters warm and as port congestion increases idle time, according to a recent I-Tech study.
As it builds up, the biological material adds drag and reduces fuel efficiency, costing shippers money and releasing greenhouse gases unnecessarily. The study found that the risk of biofouling accumulation increases significantly when a vessel idles or is in warmer water.
"Fouling takes place significantly faster in warm, tropical waters. Ships exposed to longer periods at anchor waiting for cargo or access to port face a larger risk of fouling than those that are moving," stated the study by I-Tech, a Swedish company that developed an antifouling paint ingredient. "It is known that vessels at idle for 14 days or more are highly exposed to the risk of barnacle growth."
Biofouling can begin within the first few hours a ship enters the water, according to the International Maritime Organization.
Read: Ocean delays turn desperate retailers to the skies, increasing emissions
Before recent congestion reached critical levels, the study estimated the number of vessels idling had already roughly doubled in the past decade.
The study highlighted a negative feedback loop. More biofouling can lead to more fuel use and higher emissions, which increases the carbon footprint. More GHG emissions can lead to higher water temperatures, which increase the risk of biofouling.
Cost and ecosystem considerations
"A vessel with just 10% barnacle coverage requires an increase in shaft power of 36% to maintain the same speed through the water," said the I-Tech study.
Since fuel usage is such a large portion of shipping costs, this increase in drag can cut deep into profits. Each hull cleaning related to biofouling can cost $15,000 to $45,000, according to the study. ECOsubasea, a Storebø, Norway-based robotic biofouling cleaner and collector, estimates that shippers can save up to 20% on fuel costs when friction from biofouling is removed.
But fuel efficiency, profit and emissions aren't the only reasons biofouling is an enemy of the shipping industry. It also brings invasive aquatic species around the world to unique marine environments where the species can damage local ecosystems.
The organization recommends routine biofouling management to reduce ship resistance and lessen threats to biodiversity. There are several anti-fouling coatings for different conditions and various cleaning techniques in the industry, though most such techniques damage coatings meant to prevent accumulation.
I-Tech developed Selektope, a metal-free, organic marine antifouling paint ingredient designed to keep barnacle larvae from attaching to ship hulls.
ECOsubasea's robotic biofouling removal solution collects what is removed from ship hulls, including any invasive aquatic species, and brings it to land to be used as a feedstock for biofuels. This gentler removal technique can be performed in the water, removes more than 97% of fouling material, and does not damage the hull's antifouling coating, according to the company.
"The savings from effective antifouling systems are estimated at more than 100 million [metric tons] of carbon dioxide for the entire shipping industry annually," the study said.
Click here for more FreightWaves articles by Alyssa Sporrer.
Related Stories:
OceanWaves: What does congestion really mean for global trade?
Report: Shipping energy mix needs 70% green hydrogen-based fuels by 2050
Amazon, Ikea commit to zero-carbon shipping fuels by 2040
Report: Sustainable marine fuels should meet expansive criteria
Image Sourced from Pixabay
© 2026 Benzinga.com. Benzinga does not provide investment advice. All rights reserved.
To add Benzinga News as your preferred source on Google, click here.
