After deployment, Ocean Cleanup’s first system behaves differently than expected. It does harvest plastic, but some of it also floats out again. What can be done?
System 001, also called ‘Wilson’, consists of a 600 metre long line of floating pipes, with the ends drawn inward. Curtains are attached under the pipes to increase the catch. The idea was that the U-shape would be driven by the wind, its opening facing leeward, thereby collecting floating debris in the middle of the U. A fleet of approximately 60 systems should remove half of the Great Pacific Garbage Patch (GPGP) in five years.
Wilson @ sea (Photo: Ocean Clean-up)
But the initial observations from the Ocean Clean-up crew state that ‘small particles float within the system’, but that ‘plastic remains in the system for a relatively short time’. Plastic occasionally escapes out of the U shape. Researchers are trying to figure out how and why that is.
The website offers an explanation. ‘There could be various reasons why plastic is not staying inside the system. We have concluded that the system does appear to be moving too slow at times (remember, to catch the plastic, we need a speed difference where the system is faster than the plastic) or, occasionally, the speed difference appears to be reversed, where the plastic is then faster than the system. At the very minimum, the system needs to be continuously traveling faster than the plastic.’
In an effort to speed up the plastic catcher, the opening of the U shape will be enlarged. The larger surface area exposed to wind and waves is expected to increase the driving force on the system, and thereby its speed. Meanwhile, the curtains beneath the floaters will continue to slow it down.
Do you have any ideas how to improve Wilson’s plastic catching capacity? Join the Ocean Cleanup project. There are more than a dozen open positions in Rotterdam alone.
First results of system 001 in action
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