Optimizing the Path Towards Plastic-Free Oceans.

This article focuses on optimizing the routing and extraction scheduling of The Ocean Cleanup’s (TOC) plastic collection system in the Great Pacific Garbage Patch (GPGP) to maximize plastic removal. The authors model the problem as a longest path optimization on a directed acyclic graph, accounting for dynamic plastic dispersion influenced by ocean currents and the system’s collection impact, which creates nonlinear, path-dependent rewards. They develop a relaxation-based dynamic programming algorithm and a search-and-bound heuristic that improve plastic collection efficiency by over 60% compared to TOC’s current strategy, validated on one year of ocean and weather data. The study also explores seasonal effects on collection efficiency, highlighting weather constraints on extraction operations, and analyzes system design trade-offs, showing that increasing system span yields diminishing returns without improving extraction capacity or speed.