(439g) Multi-Scale Testing of Solid Oxide Electrolysis Cells, Stacks, and Systems

The production of green hydrogen is a nascent field with many emerging technologies. T The scale of green hydrogen for existing and anticipated applications is to increase from 1 million metric tons per year to 10 million metric tons. The immediate need for the increased capacity of green hydrogen production to meet demand this demand requires substantial investment in all available technologies to decarbonize as rapidly as possible. A significant amount of progress has been made over the past several years to improve the economics and reliability of solid oxide electrolysis cell (SEOC) technology. These improvements in SOEC technology allow for the technology to meet some of the increasing demand for green hydrogen and decarbonizing the hydrogen sector. The work being done at Idaho National Laboratory is an effort to validate and provide reliable third-party data on the performance and endurance of current commercial stack offerings. Stack testing at scales between 3 kW and module testing at levels of 100 kW are discussed. Button cell operational data and degradation rates up to 3,000 hours are compared favorably with stack operational data up to 4,000 hours. Through cost sensitivity analysis, we highlight the most significant challenges observed in hydrogen cost and discuss the impact of stack longevity at full commercialization. Finally, we demonstrate stack operation under dynamic load conditions to better reflect the expected operational characteristics needed to match green electricity. At the stack level, a commercial supplied has demonstrated multiple H2 production cycles ramping from 90% load to no load in less than 10 minutes. The stack also operated with instantaneous load and unload cycles. Through the comparisons of operational scales, we conclude that dynamic operation of cells, stacks and systems is feasible. The dynamic operation provides economic advantage to assist in meeting technical targets set by the Department of Energy in pursuit of the hydrogen Earthshot goal of $1/kg by 2031.