The main changes have been the switch from a moored system to a drifting system, and later to an active system. We learned this has many advantages: higher plastic capture efficiency; reduced deployment- and maintenance costs; reduced risk of system damage due to lower forces from wind, waves, and currents to name a few.
From System 001, we learned that the system suffered from fatigue issues, and was not able to keep a sufficient speed difference with the plastic. The knowledge gained from System 001 was implemented into a redesign: System 001/B, a smaller, modular version, that could be adjusted offshore, if necessary. During the deployment of System 001/B, we also learned that slowing down the system (versus speeding it up) created the most consistent speed difference between the system and the plastic, allowing the plastic to concentrate and remain inside the system.
Following our trials with System 001/B, we concluded that we could not effectively scale up with this design. Therefore, with System 002 we developed a new approach that uses active propulsion to continuously move faster than the plastic. With an actively propelled system, we will be able to catch more plastic quicker and more efficiently because now we can – contrary to the passive approach – steer the systems towards areas with high concentrations of plastic.