New algorithm maximises ocean clean up

When Jean and Baizhi joined the project last year, we were already quite advanced in the assessments we were making, such as how big we could make the system; and we had built a net with a positive environmental impact. For the long-term analysis, we also had things in place, then they came up with the algorithm. 

Because the plastic isn’t uniformly distributed, we needed a different steering strategy to go where the plastic is. Until then, we had a slightly naive approach to steering. Though we weren’t exactly randomly steering through the Great Pacific Garbage Patch, we were taking a short-sighted approach – such as ‘Where’s the highest-density region, and how quickly can we get there?’ Jean and Baizhi’s algorithm plans the trajectory one week ahead; that really optimises the plastic yield and helps us clean the patch efficiently.

So far we’ve had positive results. We’ve seen we’re able to increase the amount collected by 30%, which in turn will decrease the number of vessels we need, as well as the duration of the operation to reach our target to eliminate 90% of floating ocean plastic by 2040.

We’re simulating with their algorithm at the moment, but soon we’ll implement their steering advice on our ships – hopefully for our last trip of 2023. We already have all the ingredients to put it in place. The simulation shows that the algorithm will make a big difference. We’re looking at possibly a 50% increase in the amount of plastic we can collect. The major step still to be taken into account is that we’ll have multiple ships, so we’ll have to do an optimisation for that. The more parameters you add, the more complex things become, but we know, in theory, for one ship it would lead to a very promising gain.

We’ve come a long way. In 2019, when we were using System 001, we collected about five tonnes of plastic debris during its whole operation. Today, with System 003, we can collect that amount in a day and a half. Though back then we were happy! 

Now it takes us five seconds to swipe an area of the ocean the size of a football pitch. In total, we’ve collected 300 tonnes of plastic. Our objective is to collect around 50 tonnes of plastic per six-week trip – that’s realistic as it takes into account that in six weeks you have 20-25 days of really harvesting.

It was with System 002 that we proved we could efficiently harvest plastic. The by-catch and the interaction with the different marine animals were also positive.

Our ocean work is almost 100% based on donations. But because we’re in international waters, it's everyone’s and no-one’s problem. Fortunately, there are still some people with pretty deep pockets. The issue is also gaining traction at international levels, such as from the United Nations. Hopefully this will help in getting our project funded more easily. 

Out of The Ocean Cleanup team I’ve been on this project the longest, for 10 years. I’ve seen it grow from just an idea to getting real plastic on deck and out of rivers. We’re fortunate to work with external parties, such as Jean and Baizhi, who are eager to help and share our passion. Working for a better future is always something to be positive about.