Objective This study addresses three critical limitations in existing research on offshore wind-powered off-grid hydrogen production: a singular focus on specific maritime scenarios, inconsistent economic evaluation frameworks, and a lack of validation for commercial-scale systems. A unified techno-economic analysis framework is constructed to reveal the economic disparities among various hydrogen production modes in both deep-sea and nearshore environments.

Method Focusing on a typical 500 MW offshore wind farm, a levelized cost of hydrogen (LCOH) model was developed to systematically compare five hydrogen production configurations across two distinct scenarios: deep-sea floating and nearshore fixed-bottom wind farms. These configurations encompass distributed hydrogen production, centralized offshore platform electrolysis, and centralized onshore electrolysis. The economic viability of each mode was validated using engineering-grade parameters.

Result The results demonstrate that nearshore fixed-bottom wind turbines coupled with centralized onshore electrolysis (Mode 5) achieve the lowest LCOH at 33.92 CNY/kg, which is 31.4% lower than that of deep-sea floating wind turbines with distributed hydrogen production (Mode 1). The LCOH for all deep-sea scenarios exceeds 40 CNY/kg, primarily due to the high capital cost of floating turbines, long-distance hydrogen pipelines, and elevated operation and maintenance expenses for offshore equipment and infrastructure. Within the same maritime zone, distributed production modes exhibit a 3.5%～7.8% higher LCOH than their centralized counterparts owing to equipment redundancy and complex maintenance logistics. Sensitivity analysis reveals that a 40% reduction in wind turbine capital expenditure could lower the LCOH of all configurations to below 40 CNY/kg.

Conclusion Strategic pathways for commercialization include: (1) cost optimization of floating turbines, electrolyzers, and hydrogen infrastructure; (2) development of localized hydrogen consumption hubs in deep-sea areas to eliminate long-distance transportation; (3) retrofitting offshore oil/gas platforms for centralized hydrogen production to achieve scale economies; (4) multi-industry integration with marine aquaculture and desalination to diversify revenue streams. These findings provide actionable insights for advancing offshore wind-to-hydrogen projects from pilot demonstrations to commercial viability.