National Renewable Energy Laboratory

Hydrogen and Fuel Cells Research

Renewable Electrolysis

Renewable electrolysis is a process that uses renewable electricity to produce hydrogen by passing an electrical current through water. Renewable energy sources such as photovoltaics, wind, biomass, hydropower, and geothermal can provide clean, sustainable electricity for our nation—contributing nearly 10% to the U.S. electricity supply.

Barriers and Solutions

Renewable electrolysis is hindered by the difficulty of producing hydrogen from renewable sources in a cost-competitive manner. To realize the potential of renewable electrolysis, the costs of renewable technologies as well as the capital requirements for electrolyzers must be lowered, and renewable electrolysis systems must be optimized.

Factors that limit widespread use of renewable technologies include inherent variability and seasonal energy production. One solution is renewable electrolysis. The hydrogen produced from renewable electrolysis can be used in fuel cells or internal combustion engines to produce electricity during peak demand or low power production. This hydrogen can also be used as transportation fuel.

Research Focus

To understand the basic principles of renewable electrolysis systems, NREL conducts systems engineering, modeling, and analysis. Researchers develop concept platforms, develop and validate component and system models, and design system assessment and optimization tools.

NREL's research examines issues related to using renewable energy to produce hydrogen through electrolysis by:

• Characterizing electrolyzer performance under variable input power conditions
• Designing and developing shared power electronics packages and controllers to reduce cost and optimize system performance
• Identifying opportunities for system cost reductions through breakthroughs in component integration
• Testing, evaluating, andoptimizing the renewable electrolysis system performance for both hydrogenproduction and electricity/hydrogen cogeneration.

Areas of Expertise

NREL has expertise in:

• Systems engineering, modeling, and analysis
• Systems integration and component development
• Characterization and testing.

Learn about the wind-to-hydrogen (Wind2H2) project, which links wind turbines to electrolyzers that pass the wind-generated electricity through water to split it into hydrogen and oxygen.

Publications and Presentations

The following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

• The Wind-To-Hydrogen Project: Operational Experience, Performance Testing, and Systems Integration (PDF 3.6 MB). K.W. Harrison, G.D. Martin, T.G. Ramsden, and W.E. Kramer. (March 2009)
• Renewable Hydrogen: Integration, Validation, and Demonstration (PDF 551 KB). K.W. Harrison and G.D. Martin. (July 2008)
• Electrolysis: Information and Opportunities for Electric Power Utilities (PDF 1.3 MB). B.Kroposki, J. Levene, and K. Harrison. (September 2006)
• Wind Energy and Production of Hydrogen and Electricity—Opportunities for Renewable Hydrogen (PDF 1.1 MB). J. Levene, B. Kroposki, and G. Sverdrup. (March 2006)
• Renewable Electrolysis Integrated System Development and Testing (PDF 941 KB). B. Kroposki. Presented at the 2006 DOE Hydrogen, Fuel Cells & Infrastructure Technologies Program Review. (May 2006)
• Characterizing Electrolyzer Performance for Use in Wind Energy Applications (PDF 814 KB). K Harrison, B. Kroposki, and C. Pink. Presented at the American Wind Energy Association's (AWEA) WINDPOWER Annual Conference. (June 2006)
• Summary of Electrolytic Hydrogen Production (PDF 720 KB). J. Ivy. (September 2004)

Contact: Kevin Harrison 303-384-7091, Todd Ramsden 303-275-3704