Sailing towards sustainability: offshore wind's green hydrogen potential for decarbonization in coastal USA

Abstract

In the pursuit of achieving net-zero emissions to combat climate change, green hydrogen is expected to be an important decarbonization vector for hard-to-abate sectors. Scaling up green hydrogen production necessitates significant resources such as renewable energy and water, presenting an opportunity for a synergistic integration with offshore wind—a largely untapped energy source with abundant potential and declining costs. In this study, we employ a systematic assessment, utilizing an optimization framework and life cycle assessment, to evaluate the economic and environmental implications of green hydrogen production offshore. We examine the two delivery pathways of direct hydrogen transport – liquefied hydrogen and compressed gaseous hydrogen for 30 coastal states in the United States and further extend the analysis to the regional level, conceptualizing offshore hydrogen hubs. Our findings reveal that under optimistic scenarios of hydrogen uptake, 75% of the nation's serviceable consumption potential of hydrogen can be fulfilled through the deployment of 0.96 TW of offshore wind capacity. This leads to a significant increase in the utilization of offshore wind resources from 1% at present to over 22% of its technical resource potential. Our assessment predicts a delivered cost range of $2.50–$7.00 per kg H₂ and life cycle greenhouse gas emissions below the 4 kg CO₂e per kg H₂ benchmark at the coast for hydrogen produced offshore. These estimates are robust over a large range of demand scenarios. Furthermore, we delve into the factors that lead to the spatial differentiation in these metrics and discuss key policy support measures to bolster the growth potential of these nascent sectors.