Journal of Geoscience and Eco Agricultural Studies

Abstract

This study introduces a dynamic subsea capture framework for hydrogen recovery that departs from con ventional production routes based on electrolysis and thermochemical conversion. Instead of generating hy drogen through energy-intensive bond dissociation, the proposed approach recovers hydrogen-bearing fluid through passive, flow-induced capture within a distributed environment. The system consists of a stationary or semi-stationary subsea unit equipped with controllable lateral openings and a sensor-guided control scheme. Relative motion is provided by ambient currents and, when needed, by short-range surface vessel movement over distances on the order of 50–100 meters. During each capture cycle, lateral openings are exposed to the surrounding flow for a short interval, allowing the chamber to fill under natural pressure and velocity conditions. The openings are then sealed and the cycle is repeated. This replaces continuous pumping and long-distance transport with discrete, geometry-driven capture events. First-order analysis indicates that the energy required per kilogram of hydrogen is on the order of 10⁶ to 10⁷ joules, substantially lower than the approximately 2×10⁸ joules per kilogram, typically associated with water electrolysis. The resulting regime is primarily capture-limited, with performance governed by local concentration, flow conditions, and cap ture efficiency. The framework is particularly relevant in subsea environments where hydrogen-bearing spe cies such as hydrogen sulfide are spatially distributed. Rather than targeting isolated reservoirs, the system performs repeated local sampling and accumulates product over time. By aligning the design with ambient hydrodynamics, the approach minimizes external energy input and simplifies system architecture. While feasi bility is site-dependent, the results establish a physically consistent and scalable basis for low-energy subsea hydrogen recovery via dynamic capture.