Author: Victoriia Grabovetska
Date/Time: April 15th, 2025 at 2pm EST
Location: EGR-0151, Glenn L. Martin Hall
Committee members:
- Dr. Katrina Groth, Chair
- Dr. Mohammad Modarres
- Dr. Yunfei Zhao
Title of dissertation: Identifying Risk Scenarios of a Solid Oxide Electrolysis Facility for Hydrogen Production at Nuclear Power Plants
Abstract: Solid Oxide Electrolysis (SOE) is a developing technology for the production of clean hydrogen. SOE is a key technology used in a high temperature electrolysis facility, named for the high temperature steam at the inlet of the electrolyzer stack. The required steam temperature of 750 ◦C, can provided via thermal energy from a Nuclear Power Plant (NPP), which also reduces the electricity required to produce the hydrogen. At present, the U.S. government and industry are researching and testing SOE designs connected to NPPs to enable commercial-scale system hydrogen production at NPPs. Commercial SOE facilities have the potential to produce clean hydrogen at a high efficiency and more flexible operating paradigms for NPPs. The deployment of these systems requires a more robust understanding of the operational hazards of the SOE facility’s design. However, to date the published literature has not presented a detailed description of the relevant hazards. This work adds to the growing body of engineering knowledge about hydrogen production facilities by identifying a comprehensive list of failure modes, mechanisms, and consequences. We describe our approach for conducting this analysis and document the SOE system we analyzed. To understand the hazards, a failure modes and effects analysis (FMEA) was conducted on a high temperature electrolysis test facility with a maximum power input of 25 kW and hydrogen production rate of 0.726 kg/hr developed at INL. All identified risk significant scenarios leading to the consequences of membrane degradation, hydrogen and oxygen mixing, hydrogen release, or nitrogen release are discussed. We identified system components that contribute to the most high-risk scenarios and proposed mitigation strategies to reduce these risks. These results were used to develop fault tree structures at a high level of abstraction to identify significant combinations of failures within the system. We created an enumerated list of risk significant scenarios. This research will assist the hydrogen stakeholders to make informed design choices to ensure safety and reliability in the continued development and deployment of SOE technologies. In the future, these results have the potential to be scaled to commercial SOE facility designs. The research provides a starting point for a comprehensive quantitative risk assessment needed to establish the risk-informed regulatory foundations that will ensure the safe and reliable deployment of solid oxide electrolysis coupled to nuclear power plants.