Article Source: The Engineer
A giant device designed to remove plastic from the sea has begun a three-week voyage from San Francisco to one of the most heavily polluted areas of ocean on the planet.
Developed by Dutch non-profit organisation The Ocean Cleanup, the system is being towed to the so-called Great Pacific Garbage Patch, a 1.6 million square kilometre area of ocean halfway between California and Hawaii that contains a concentrated accumulation of an estimated 80,000 metric tons of plastic waste.
Brainchild of Dutch inventor Boyan Slat, the technology consists of a 600-meter-long U-shaped floating barrier with a three-meter skirt attached below. The barrier provides buoyancy and prevents plastic from flowing over it, whilst the skirt stops debris from escaping underneath.
The system – which has attracted more than $31.5 million funding from a host of investors – has no power source, but is instead propelled passively by the wind and the waves, allowing it to catch and concentrate plastic debris in front of it. Due to its shape, debris is funnelled to the centre of the system where it will be scooped up by ships once every six weeks.
Solar-powered and satellite-connected sensors, cameras and navigation lights communicate the position of the device to passing marine traffic and provide the Ocean Cleanup team with data on the system’s performance.
The current trial follows a number of scale model tests, research expeditions, and a trial of a 100-metre segment of the barrier in the North Sea back in 2016.
Whilst some scientists have claimed that the system could prove damaging to sea-life attracted to the algae that grows on the plastic, the group claims that the slow speed of the system and the fact that it doesn’t involve any nets mean that its impact on wildlife will be negligible.
Commenting on the launch of the technology, Boyan Slat said: “Today’s launch is an important milestone, but the real celebration will come once the first plastic returns to shore. For 60 years, mankind has been putting plastic into the oceans; from that day onwards, we’re taking it back out again.”
If the current trials prove successful, the group hopes to put a fleet of around 60 systems in the Great Pacific Garbage Patch, which it claims would be able to clear up around 50 per cent of the waste within five years.
With an estimated 12.7 million tonnes of plastic ending up in the ocean each year (profoundly impacting marine life, and ultimately entering human food chains) the group’s ultimate aim is to reduce the amount of plastic in the world’s oceans by at least 90 per cent by 2040.