In May 2018, a 120-meter section of the world’s first ocean cleanup system was towed out of San Francisco Bay into the Pacific to conduct a two-week tow test. The performance of the system during the test left the team feeling more confident about the design and has exemplified that it is ready for the challenge it is set to face in the Pacific.
The tow test was conducted in order to analyze the screen behavior under towing conditions and to test the durability of both the screen and the floater.
We are happy to report that the entire section performed satisfactorily. Of the minor issues that the screen did endure, most were identified during earlier testing on the North Sea; therefore, the final design had already been adjusted according to these findings. These favorable results mean we can continue the assembly of the full system and prepare for launch in the coming months,
…Arjen Tjallema, Technology Manager at The Ocean Cleanup Foundation said in an official update.
Approximately 50 nautical miles from the Golden Gate Bridge, the team towed the unit in various speeds and orientations relative to the wind, current and waves. This tow test piece was 120 meters (two 60-meter sections) of the 600-meter System 001, that is set to be its first, fully-functioning ocean cleanup system. It consisted of the outer sections of the floater elements that will be used on the final system and a tapered, three-meter-deep test screen section (the tapering effect is a design that will be replicated on the final screen design as well).
In total, the entire test lasted about two weeks and gave the team plenty to observe.
Overall, the tow test unit behaved very well. It endured a severe storm and withstood the forces of the ocean during this time. The floater, that has been designed to bend and flex with the waves (think snake-like motions), did exactly that – as earlier demonstrated in scale model testing – and did not show any signs of damage from this performance. The screen and floater confirmed the behavior we observed on our North Sea Prototypes, in scale model tests and in our numerical models. The weaknesses of the screen section (design version 1.1) on the tow test unit have already been taken into account for the design of the new screen (version 2.0) that is now in production for the full system.