The National Energy Technology Laboratory (NETL) has published The Hydrogen Safety Review for Gas Turbines, SOFC, and High Temperature Hydrogen Production to review and summarize the unique safety challenges involved with the production, transportation and storage of hydrogen.
The Review is part of NETL’s Hydrogen Safety Field Work Proposal to support the US Department of Energy’s Office of Fossil Energy and Carbon Management’s strategic vision for safe, widespread and large-scale production and utilization of hydrogen as a carbon-free energy storage medium.
Hydrogen power could be a key contributor to a net-zero carbon emissions energy sector, but many technological and cost challenges still remain especially in matters of handling hydrogen safely. It’s our hope that this report will serve as a valuable resource for stakeholders in charting future hydrogen projects and assist in building safe, sustainable bulk hydrogen production and power generation infrastructure.—Ben Chorpening, supervisor of the NETL’s Advanced Systems Integration Team and technical portfolio lead
Hydrogen is a versatile molecule, useful as a clean energy carrier and chemical precursor. Hydrogen is the most abundant element in nature, and it currently plays an important role in chemical production and petroleum refining. Hydrogen can be extracted from different sources such as fossil fuels, biomass, waste plastics and water. When combined with carbon capture and storage, natural gas reforming and gasification are well positioned to produce large quantities of hydrogen from a variety of feedstocks, including waste coal with biomass, waste plastics or municipal solid waste.
New technologies such as solid oxide electrochemical cells (SOEC) and chemical looping are also being developed for hydrogen production.
However, hydrogen does have several safety concerns that must be contended with through careful engineering design and diligent operations.
For example, compared to natural gas, hydrogen has an increased flammability range and lower minimum ignition energy, which increases the likelihood of a fire starting from a hydrogen leak. The lower ignition energy makes smaller sparks a concern. Hydrogen flames are nearly invisible, making small fires difficult to notice and posing increased risk of harm to unaware personnel.
There are also matters of operating costs and facility designs to consider when using hydrogen safely. From a mechanical design standpoint, hydrogen also causes embrittlement in many steels and alloys. Consequently, safe material selection for hydrogen results in higher system costs than with natural gas.
In addition, the form of hydrogen stored may have a significant impact on safety issues with production and utilization technologies. Liquid hydrogen and ammonia offer potential benefits for storage and transportation of hydrogen but pose some additional safety hazards.
The report documents the unique safety issues for solid oxide fuel cells (SOFCs) and gas turbines fueled from hydrogen, and production of hydrogen from fuel reforming, gasification, chemical looping and SOEC. This report includes the approaches presently used to address hydrogen safety and identifies some potential technology advancements to improve the performance and reduce the cost for safety monitoring.
The hydrogen safety report examines these concerns and more in detail, offering a valuable resource for future hydrogen endeavors.