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Ocean Cleanup Project struggles to get its system up to speed

By Nick Lavars
December 6th, 2018


Dubbed Wilson, the Ocean Cleanup Project’s first barrier is designed to work like a giant plastic-eating Pac-Man.

Around six weeks have passed since the Ocean Cleanup Project installed its first trash-catching system in the Pacific, and it hasn't exactly been smooth sailing for the huge floating barrier so far. The team reports that attempts to overcome some initial teething problems haven't exactly gone to plan, with the team searching for new solutions to bring its system up to speed.

Dubbed Wilson, the Ocean Cleanup Project's first barrier is built to work like a Giant Pac-Man, using its U-shaped form with a floating barrier on the surface and a three-meter (10-ft) skirt dangling below to scoot through the Great Pacific Garbage Patch collecting rubbish as it goes.

For that to work, the barrier needs to move faster than the plastic it is trying to collect, and in theory it should do just that. Because it is propelled through the water by a combination of the ocean currents, surface waves and the wind through the air, it should reach greater velocities than the floating trash that is powered by the ocean currents alone.

But after a month of observations, the team found the system was collecting trash as hoped, but much of it was escaping after a relatively short time. This is because the system is unable to build up enough speed to hold the trash inside its u-shaped mouth, and is at times even being outpaced by the plastic.

The initial remedy was to try and widen the mouth by 60 to 70 m (200 to 230 ft), which should create a larger surface area for the wind and waves to push it along, kind of like replacing a small kite with a larger one. This solution appeared relatively simple to implement, required just a lengthening of the lines that hold the barrier in its u-shaped form.

Unfortunately, this hasn't quite done the trick, with the team reporting this week that the line extension failed to widen the mouth of the system and therefore hasn't increased its speed. Workers did manage to pull some large ghost nets from the water while it did the tinkering, but in order to get the system performing as intended the team has to return to the drawing board.

"Wilson Update: the closing line extension did not effectively increase the span of the system and, therefore, the speed did not improve," The Ocean Cleanup crew tweeted. "Further approaches to widen the u-shape are being evaluated and tested by the team."

This is by no means a disaster as the team had never expected everything to go to plan and knew tackling a problem as big as the Great Pacific Garbage Patch, an accumulation of plastic waste three times the size of continental France, would involve plenty of problem-solving on the fly.

If it can get this initial proof-of-concept system up and running, it hopes to use it as a blueprint for as many as 60 replicas. According to its modeling, a fleet this size could collect half of the plastic in the patch every five years.

Source: The Ocean Cleanup (Twitter) https://tinyurl.com/y9wn9v2h

https://newatlas.com/ocean-cleanup-speed/57564/