Performance of Polymer Electrolyte Membrane Water Electrolysis Systems: Configuration, Stack Materials, Turndown and Efficiency

Abstract

A cell model is developed and validated to analyze the performance of polymer electrolyte membrane water electrolysis (PEMWE) stacks and systems. It is used to characterize the oxygen evolution reaction (OER) activity on a TiO2-supported IrO2 catalyst and an unsupported IrO2 powder catalyst. Electrochemical, stack, and system thermoneutral potentials are defined and determined for isothermal and non-isothermal stack operation. Conditions are determined under which the system thermoneutral potential or flammability of H2 in the O2 anode stream limits the stack turndown and operating temperature. Performance is analyzed of a complete PEMWE system with an electrolyzer stack containing an IrO2/TiO2 anode catalyst (2 mg/cm2 Ir loading) and N117-like membrane mitigated for H2 crossover, anode balance-of-plant (BOP) components, cathode BOP system with temperature swing adsorption for H2 purification, and electrical BOP system with transformer and rectifier. At the rated power condition, defined as 2 A/cm2 at 1.9 V, 80 °C, and 30 bar H2 pressure, the stack/system efficiency is 65.3%/60.3% at beginning of life (BOL), decreasing to 59.3%/53.9% at end of life (EOL). The peak stack/system efficiency is 76.3%/70.2% at BOL, decreasing to 71.2%/65.6% at EOL. Improvements in catalyst activity and membrane are identified for a 50% increase in current to 3 A/cm2 at 1.8 V.

Strategic Model for Yellow Hydrogen Production Using the Metalog Family of Probability Distributions

“…Scientists are more accurate than sellers when providing data on the efficiency of electrolyzers. PEM electrolyzer data were also found in the literature [119]. At the rated power condition, defined as 2 A/cm 2 at 1.9 V, 80 • C, and 30 bar H 2 pressure, the stack/system efficiency is 65.3%/60.3% at beginning of life (BOL), decreasing to 59.3%/53.9% at end of life (EOL).…”

“…The hydrogen fuel is then powered by hydrogen fuel cells, which generate electricity and heat while on board the vehicles. The types of fuel cells most commonly used in the automotive industry are PEM [118,119], SOFC [120], and MCFC [121].…”

Hydrogen Carriers: Scientific Limits and Challenges for the Supply Chain, and Key Factors for Techno-Economic Analysis

“…Nevertheless, its production is still highly dependent on fossil fuels and only 4% is derived from water electrolysis [1], and so relevant efforts are required in making hydrogen an energy carrier suitable for a sustainable green economy. In the last decades, researchers have focused on several kinds of water electrolyzers, such as polymer electrolytes membrane (PEMWEs) [2,3], alkaline water electrolyzers (AWE) [4,5], and solid oxide electrolyzers cells (SOEC) [6,7], which differ in component materials and operating conditions. Moreover, in green hydrogen production, electrolyzers must exploit the excess energy from the renewable energy sources (RES) grid, and then, in a reasonable scenario, hydrogen is not immediately used when produced, and so storage systems are required [8][9][10][11][12][13].…”