As the U.S. faces significant challenges in scaling up production of hydrogen in cost-effective and environmentally friendly ways, a new Cornell study outlines strategies to meet up to 75% of the nation's future hydrogen demand by harnessing offshore wind energy.

The demand for hydrogen is expected to grow significantly in the coming decades, with production from renewable energy sources such as offshore wind turbines, rather than fossil fuels, being essential for hydrogen to be considered "green." However, it would take 0.96 terawatts of offshore wind capacity to produce 75% of the nation's serviceable consumption potential of hydrogen, according to the Cornell study published in the journal Energy & Environmental Science.

Installing that much capacity would require the U.S. to drastically increase its use of offshore wind energy, going from using just 1% of its technical resource potential to over 22%, said Fengqi You, the Roxanne E. and Michael J. Zak Professor in Energy Systems Engineering, who co-authored the study with graduate student Rishi Kaashyap Balaji.

"This is a massive increase in offshore wind energy production, but pursuing this approach would not just provide an opportunity for the U.S. to spur growth in an important energy sector, but also circumvent potential land and water use challenges from developing large-scale renewable energy infrastructure domestically," said Fengqi You, who is also a senior faculty fellow at the Cornell Atkinson Center for Sustainability.

The study takes a comprehensive approach to analyzing the economic and environmental impacts of offshore wind-based hydrogen production by employing an optimization framework, life cycle assessment, and multi-scale spatial analysis. It examines two delivery methods—liquefied and compressed gaseous hydrogen—while incorporating wind speed data and state-level hydrogen demand, among many other parameters.

"A key finding is that transporting compressed gaseous hydrogen via pipelines offers clear economic and environmental advantages over shipping liquefied hydrogen," Balaji said.

"The cost and energy needed to liquefy hydrogen to -253 degrees Celsius make the liquefied hydrogen route very expensive. However, this method still warrants consideration, as building extensive pipeline infrastructure could prove to be a monumental challenge."

The study also conceptualizes 'offshore hydrogen hubs'—states clustered into geographic regions that broadly align with the U.S. Department of Energy's Regional Clean Hydrogen Hubs program announced in 2023. The hubs comprise the necessary infrastructure for production, storage and end-use of clean hydrogen, optimizing facility location and bringing cost savings up to 30% through shared infrastructure, according to You.

"The East Coast emerges as a prime region of interest for offshore wind-based green hydrogen production because of high wind speeds, significant regional demand, abundant surplus potential and promising prospects for establishing export-oriented facilities to serve net-importers of hydrogen in European markets," You said.

Using the study's optimal pathways, producing hydrogen offshore could cost between $2.50 and $7.00 per kilogram, with greenhouse gas emissions well below the 4 kilogram carbon-dioxide-equivalent benchmark. This qualifies green hydrogen for production tax credits under the Inflation Reduction Act, further increasing its market competitiveness, said You.

"Additional supportive policies, such as carbon pricing mechanisms, will be crucial," You added. "The century-old Jones Act, for example, complicates offshore projects by requiring domestically constructed and crewed ships, yet as of 2020, no U.S.-flagged ships could perform tasks like assembling turbines at sea. Our work discusses the importance of flexible policies to address these practical challenges to the industry's growth."