3. High-temperature electrolysis

The principle of a basic high-temperature electrolysis (EHT) cell is shown schematically in Figure 3 . This technology does not require a noble metal catalyst and uses rare earth elements, which are less expensive. Similar to low-temperature electrolysers, a high-temperature electrolysis cell consists of two electrodes and an electrolyte, which separates the electrodes and conducts oxide ions O ^2– . The half-reactions occurring at the anode and cathode are given by the equations (9) and (10)