Enhancing the feasibility of offshore floating wind energy by hydrogen production: A case study for Japan

Abstract

Offshore Floating Wind Energy (OFWE) presents a promising yet underdeveloped sector due to its higher costs and engineering complexities compared to fixed-bottom systems. Unlike fixed-bottom systems, OFWE isn't restricted by water depth, offering over four times more ocean area for deployment. This flexibility allows for positioning wind farms further offshore where wind speeds are higher and more consistent, maximizing energy generation potential. However, the current viability of OFWE heavily depends on governmental subsidies to remain competitive.
Integrated Systems (IS) have emerged as a promising solution to address the need for affordable, scalable, and transportable renewable energy storage. IS combines offshore wind farms with hydrogen production systems, aiming to enhance the Techno-Economic Performance (TEP) of OFWE and potentially render it economically feasible.
A case study focusing on Japan's Goto City Wind Farm illustrates the challenges and opportunities associated with OFWE and IS integration. Japan, with its ambitious wind energy goals and limited suitable areas for fixed-bottom wind energy, serves as an ideal location for such a study. Additionally, Japan's interest in integrating hydrogen into its energy mix further underscores the relevance of this research.
The initial analysis of the Goto City Wind Farm without IS integration revealed its lack of economic viability over its operational lifetime. However, by integrating additional components for hydrogen production, such as desalination, electrolysis, and hydrogen carrier configuration units, the project's Techno-Economic Performance was significantly enhanced.
One key advantage of the IS approach lies in its flexibility in power allocation between grid supply and hydrogen production. By dynamically adjusting power allocation based on prevailing market conditions and a predetermined switch price, the IS can optimize revenue generation and adapt to fluctuating energy markets.
Further analyses, including examinations of different hydrogen carrier configurations, capacity assessments, scenario analyses, and sensitivity analyses, were conducted to comprehensively evaluate the TEP of the system.
Results indicated that hydrogen production during periods of low power prices substantially improved the TEP of the Goto City Wind Farm, making it economically feasible by the end of its operational lifespan. Moreover, the ability to switch between hydrogen production and grid supply mitigated risks associated with future uncertainties in hydrogen and power prices.
In conclusion, integrating hydrogen production with OFWE through Integrated Systems offers a promising pathway to enhance TEP and improve the economic viability of offshore wind energy projects, contributing to a more sustainable energy future.