Offshore wind-to-green hydrogen: a comprehensive review on current challenges, techno-economic analyses, environmental implications, and potential risks

Offshore wind energy is pivotal in strengthening grid stability and expanding energy storage capabilities, particularly through its integration with green hydrogen production. Nevertheless, the limited deployment of floating offshore electrolysers means that the effects of marine conditions on the cost and efficiency of hydrogen production are still challenging. A state-of-the-art review of offshore wind green hydrogen production systems (OWHS) is provided, utilizing electrolysis and seawater, with in-depth emphasis on production pathways, global pilot projects, techno-economic assessment, and environmental implications of OWHS. In addition, recent studies on coupling configurations of different types of electrolysers with offshore wind farms are assessed to evaluate their capital costs and operational efficiency toward scalable implementation. It is observed that the durability of offshore platforms and advancing electrolysis systems remains a critical technical hurdle. High installation and operational costs further complicate large-scale deployment. These challenges can be mitigated by scaling up production, adopting flexible financing strategies, and utilizing cost-effective solutions such as modular systems and commercially available components. Among the available electrolyser technologies, proton exchange membrane electrolysis cells are currently preferred as the optimal coupling configuration due to its compact design, high hydrogen production efficiency, and ease of maintenance. From an economic perspective, offshore green hydrogen remains costlier due to transportation challenges, infrastructure expenses, and elevated maintenance requirements. The high cost of OWHS needs government sponsorship and financial systems of scale for diminution. Moreover, strategic investments, subsidies, and public-private partnerships are crucial to making offshore green hydrogen cost-competitive with other low-carbon alternatives.