Innovative anti-biofouling technologies can make shipping more eco-friendly

June 23, 2011 by Annette Ostrand

Organisms that stick to the lower structures of ships increase fuel consumption and costs of maintenance substantially. Currently, the organisms are killed with toxic biocides, but these chemicals need to be removed to protect our environment. Researchers are trying to develop environmentally friendly anti-biofouling technologies, such as nano-structured surfaces that make organisms fall off when the ships move.

Organisms, such as algae and barnacles, sticking to the lower structure of ships are increasing the required propulsive power. It is estimated that ships’ could be reduced by up to forty percent by removing those . Erosive systems containing biocides are mainly used for this purpose. However, the use of eco-friendly alternatives such as silicon based fouling release coatings, nearly all enhanced with an oil additive, have increased lately. Researchers at GE Global Research Center in the U.S. have shown that organisms react differently to the various silicone fouling release coatings, and type crossed with oil type is very important when it comes to establishing an organism’s attachment strength magnitude.

However, there is a need for improved eco-friendly alternatives and researchers are working on solutions. For example, scientists at the University of Gothenburg in Sweden have developed what they call a “low emission” approach where avermectins, a class of antibiotics, are included. Only very small amounts are released, since the substances in the coating are tightly associated with the binding matrix agent. The scientists found that 1mg avermectin/gr coating very effectively hindered adult barnacles from colonization, but a similar coating did not disturb barnacle larvae. The reason is that the barnacles first encounter the avermectin when they try to stick tighter to the surface and the avermectin then make them detach. This principle was named post settlement inhibition (PSI) because this coating only seems to influence adult barnacle growth.

Another innovation that neither involves toxic substances currently used nor nanoparticles, has been developed by researchers connected to the European Commission-funded project AMBIO (Advanced Nanostructured Surfaces for the Control of Biofouling). Their coating technology that can replace the toxic biocides technology is instead based on nano-pattering. Molecules within their innovative paint will arrange themselves in a chequeboard pattern were hydrophobic nanosized points are combined with hydrophilic nanosized points. This texture makes it very hard for and barnacles to hold on to the surface and the water’s friction will remove them.

Although a coating alternative that do not release any toxic substances into the environment appears to be the safest choice, the AMBIO coating technology will first be studied extensively in a real world setting to make sure it has the right properties, for example that it can last five years on ships, before it can become commercially available.

Explore further: Shark skin saves naval industry money

Related Stories

Shark skin saves naval industry money

July 15, 2005

Covering ship hulls with artificial shark skin could help ships sailing smoothly. The growth of marine organisms such as barnacles on ship hulls is a major cause of increased energy costs in the naval industry. Shark skin ...

First images of barnacle larva's footprint

October 27, 2008

( -- The fouling or growth of sea organisms, such as barnacles, on ships’ hulls causes damage costing many billions of euros annually. In order to prevent this fouling, In Yee Phang of the University of Twente ...

Gene that causes barnacles to avoid ship hulls identified

August 16, 2010

The substance medetomidine has proved effective in preventing fouling of ship bottoms. Researchers at the University of Gothenburg have now identified the gene that causes the barnacle to react to the substance, opening up ...

Recommended for you

Gold nanomembranes resist bending in new experiment

October 9, 2015

The first direct measurement of resistance to bending in a nanoscale membrane has been made by scientists from the University of Chicago, Peking University, the Weizmann Institute of Science and the Department of Energy's ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.