Abstract: Offshore wind resources in deep-water is more abundant and will be one of the main development trends in the next few years. However， offshore wind development faces many challenges such as the power transmission and consumption. It needs new development models and technological innovations to be promoted. Hydrogen production through offshore wind would improve the power system flexibility and safety， and could be used as renewable energy storage to achieve large-scale and long-term storage. Based on the market price and literature， the tech-economic comparison and evaluation are carried of onshore off-grid hydrogen production and offshore hydrogen production with pipeline from the levelized cost of hydrogen and internal rate of return. Based on the whole life cost， the levelized cost of hydrogen production through offshore with pipeline is lower and the CAPEX and OPEX of water electrolysis system have a significant impact on the LCOH. In terms of economy， offshore wind will obtain higher returns than offshore hydrogen production if all electricity could be imported to the power system.

Key words: offshore wind, electrolysis water, tech-economic evaluation