The National Renewable Energy Laboratory (NREL), in partnership with Xcel Energy, launched a wind-to-hydrogen (Wind2H2) demonstration project at the National Wind Technology Center in Golden, Colorado. The Wind2H2 project links wind turbines to electrolyzers, which pass the wind-generated electricity through water to split the liquid into hydrogen and oxygen. The hydrogen can then be stored and used later to generate electricity from an internal combustion engine or a fuel cell. The goal of the project is to improve the system efficiency of producing hydrogen from renewable resources in quantities large enough, and at costs low enough, to compete with traditional energy sources such as coal, oil, and natural gas.
This page describes the Wind2H2 system components, research focus, and project benefits, and provides links to related publications.
System Components
The Wind2H2 project uses two wind turbine technologies: a Northern Power Systems 100-kW wind turbine and a Bergey 10-kW wind turbine. Both wind turbines are variable speed; the blades speed varies with wind speed. Such wind turbines produce alternating current (AC) that varies in magnitude and frequency (known as wild AC) as the wind speed changes.
The energy from the 10-kW wind turbine will be converted from its wild AC form to direct current (DC), and then used by the electrolyzer stack to produce hydrogen from water. The energy from the 100-kW wind turbine will be "picked off" from its existing controller, which produces a DC bus between 750 and 800 V. Since this voltage is too high for the electrolyzer stacks, NREL will design power electronics to make the DC-DC conversion.
Two HOGEN 40RE proton exchange membrane (PEM) electrolyzers from Proton Energy Systems and one Teledyne HMXT-100 alkaline electrolyzer will produce hydrogen and oxygen from water. NREL will examine the issues related to the integration of these technologies as well as the operation of electrolyzers with different gas output pressures.
After compressing the hydrogen, it will be stored for later use in a hydrogen internal combustion engine where it will be converted to electricity. The electricity will be fed into the utility grid during peak demand hours.
To learn more, view the Wind2H2 animation or video.
Research Focus
NREL research will focus on the following areas:
Explore system-level integration issues related to multiple electrolyzers that produce hydrogen gas at different pressures
Evaluate the ability to integrate energy from variable-speed wind turbines directly to the hydrogen-producing stacks of commercially-available electrolyzers
Determine the system impacts and ability of each electrolyzer technology to accommodate the varying energy input from wind turbines and photovoltaics
Quantify system-level efficiency improvements and cost reductions by designing, building, and integrating dedicated wind-to-electrolyzer stack power electronics to enable closer coupling of wind-generated electricity and electrolyzer stack requirements
Gain operational experience of a hydrogen production facility, including the compression of product gas and the use of a hydrogen internal combustion engine to generate electricity during peak demand hours
Evaluate appropriate safety systems and system controls for the safe operation of hydrogen production technologies with varying wind energy input
Demonstrate operation of a wind-to-hydrogen system to enable evaluation of actual system costs and identify areas for cost and efficiency improvements
Explore operational challenges and opportunities related to energy storage systems and their potential for addressing electric system integration issues inherent with variable wind energy resources.
Project Benefits
The Wind2H2 project offers many benefits. It allows researchers to explore how to make hydrogen without producing greenhouse gasses or other harmful by-products. Currently, most hydrogen is "reformed" from natural gas or other fossil fuels by stripping the hydrogen atoms out. This process creates greenhouse gas emissions and eliminates some of the environmental benefits. Hydrogen is also produced through electrolysis using sources of electricity (such as fossil fuels) that generate air emissions.
Other key project benefits include:
Creating synergies from the co-production of electricity and hydrogen
Addressing the variable nature of wind power by storing hydrogen for later use, creating a ready source of electricity for when the wind doesn't blow or the demand for electricity is high
Producing hydrogen for use in vehicles
Comparing multiple electrolyzer technologies to gauge their efficiencies and abilities to accommodate the variable input power of wind energy
Achieving efficiency gains though a unique, integrated AC-to-DC and DC-to-DC connection between the wind turbines and the electrolyzer stacks.
Related Publications
The following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.
- Renewable Hydrogen: Integration, Validation, and Demonstration (PDF 551 KB)
- Electrolysis: Information and Opportunities for Electric Power Utilities (PDF 1.3 MB)
- Wind Energy and Production of Hydrogen and Electricity—Opportunities for Renewable Hydrogen (PDF 1.1 MB)
- Renewable Electrolysis Integrated System Development and Testing (PDF 841 KB)
- Characterizing Electrolyzer Performance for Use in Wind Energy Applications (PDF 814 KB)
- Summary of Electrolytic Hydrogen Production (PDF 719 KB)
For more information, contact Kevin Harrison at (303) 384-7091 or Todd Ramsden at (303) 275-3704.
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