Laboratory alkaline electrolyzer test bench for high pressure and temperature (85 °C and 30 bar)
Pilot and Demonstrator Project
Funding: Research Programme Hydrogen, Swiss Federal Office of Energy SFOE
To bridge the gap between industrial applications and laboratory-scale research on alkaline electrolysis, a custom-made pilot alkaline electrolyzer working at high temperature and pressure (e.g. 85°C, 30 bar) was acquired (VOLTIANA, H2 Nitidor, I) and set up at Empa. Based on a stack of 5 to 10 cells (100cm2 active area each), this device simulates realistic operation conditions. At the same time, it features additional characterization tools to assess optimized cell designs and newly developed components and materials to test their mechanical and electrochemical stability and durability as well as to evaluate their influence on cell voltage (efficiency) and gas purity.
Building up such a pilot electrolyzer turned out to be technically challenging, as downscaling complicates the pressure management and leveling routines in the system. Although several issues currently remain with gas analyses and accurate control of the process temperature, this pilot electrolyzer is the only one available of this kind. It is of high importance to advance the alkaline electrolysis technology, in particular with respect to application with intermittent renewable energy sources.