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ECOsubsea scrubs ship slime to save the seas

Ecosubsea cleans the "bio-fouling," accumulated sea slime on hulls, that makes ships less efficient and threatens ocean ecosystems.


Ecosubsea learned that you cannot just harvest and harvest, or you damage the oceans. You need to ensure that nature is in balance.

This article originally was published by Climate & Capital Media and is reprinted with permission.

At the end of 2020 an estimated 62,100 vessels were plying the oceans, all picking up microorganisms, plants, algae and small animals as they travel. This growth on ships, known as "biofouling," means less efficiency, more shipping fuel and more greenhouse gas emissions. It also means that species are transported from one location to another, often causing invasive impacts on native ocean life, more so as the oceans warm. In extreme cases, biofouling can damage ship propellers and other equipment and make them unseaworthy. 

That’s what got Norwegian brothers Tor and Klaus Østervold to dedicate 13 years of their lives to develop Ecosubsea. Founded in 2008 in Austevoll, Norway, the brothers have focused on developing a robotic cleaning system to remove biofouling in an environmentally friendly way. Since 2012, their pilot Ecosubsea station has scraped more than 100,000 kilos of fouling off ships — a carbon equivalent of 3 million tons.

"Our vision from the very beginning was how to safely transform a pressing environmental problem, biofouling, into a business profit for shipowners and ports by making shipping greener," Tor Østervold said. "For over a decade, we’ve fine-tuned our technology and earned licenses for operating in ports with strong environmental benchmarks."

Østervold says from age 13, he was part of his grandfather’s family fishing business in the North Atlantic. In the 1960s, he watched the herring population that the fleet depended on disappear from overfishing.

"We learned that you cannot just harvest and harvest, or you damage the oceans," he said. "You need to ensure that nature is in balance." 

In the past, biofouling on ships was treated with toxic biocides that are harmful to ocean life, by applying non-stick coatings to ships, which wasn’t always effective, or by expensive and time-consuming hull cleaning. The Ecosubsea team created a quick way of cleaning that doesn’t damage ships’ hulls that can be done while ships are unloading and loading in port. The robotic system runs underwater and collects a ship’s fouling of bio-organisms for processing on land. 

"My brother and I were studying for master’s degrees in international shipping at the University of Plymouth and were lucky enough to be part of a project where we developed robots that were cleaning aquaculture nets," Østervold said. "We approached Maersk, the biggest shipping company in the world at the time, and asked them, ‘Do you see a need for a sustainable way to deal with biofouling on ships that could potentially save you money?’ They said certainly, it’s a big nut that hasn’t been cracked. That’s how we got started."

Their pilot ECOsubsea station has scraped more than 100,000 kilos of fouling off ships — a carbon equivalent of 3 million tons.

He said the Ecosubsea remotely operated robot is designed with the Batmobile in mind — "hunting down the bad guys" — and that it is loaded onto ships while they are still at sea so that when a cruise vessel or cargo ship comes to port, it can be cleaning while passengers are getting on and off and goods are loaded. The robot goes back and forth underneath the hall and it takes off all the biofouling, then sends it up to the shore to be filtered and treated. The entire cleaning process takes only 8.5 hours, and 97.5 percent of what’s removed from the hull is collected. 

"At our operation in Southampton, in the U.K., we are working with Veolia to collect the biomaterial and they are using this to make biogas for greener electricity for surrounding households."

Because cleaner ships use less fuel, Østervold explains that the Ecosubsea system can save a ship 5 percent to 15 percent in fuel costs and cut greenhouse gas emissions by the same amount. Today, the company estimates it has saved ship owners 38 million tons of heavy fuel oil. The company has won a slew of awards for both innovation and environmental impact.

Today, the company estimates it has saved ship owners 38 million tons of heavy fuel oil.

"We can save a massive amount of fuel. It really makes the business case," he continued. "Cleaning 300 large cargo ships with our system can indirectly reduce CO2 emissions by 2.11 million metric tons, and you can also stop non-native species hitchhiking over the oceans. If we could clean just 10 percent of the world’s ships, we would save north of 50 million tons of CO2 a year. That’s the same as the annual emissions from Norway." 

Ecosubsea has cleaned more than 1,000 vessels, set up a business in Southampton as well as Norway, launched its International Centre of Excellence in 2018 and operates in 10 ports, primarily in Europe. The brothers are ready to go global with contracts new with Carnival, Hoegh Autoliners and WWL Ocean, among others. 

The company is also capitalizing on increasingly strict regulations surrounding environmental safety in seaports. New regulations have been implemented in California, Australia, New Zealand and Rotterdam. 

"We see the EU, China and the U.S. are discussing putting a tax on carbon for the shipping industry so cutting emissions really matters," he said. "We are leading on this technology worldwide, and that gives us a sense of urgency, that we need to move fast."

Ecosubsea received a number of grants early on and Østervold says there has been a real shift in funders only being interested in solving the shipping problem and making it profitable to reduce environmental impact. 

"I think it’s been a massive change over the last 10 years," he continued. "I think that with sustainability, looking at entrepreneurship is really important. There’s so much talk about the challenges of being sustainable but too little recognition that it is the world’s biggest opportunity." 

Østervold adds that the pandemic has brought about another positive shift. "People are looking for purpose now and how to work together. That’s what makes me optimistic." 

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