| Type | a [-] | b [K] |
| Acidic (PEM) | 3.005 | −795.2 |
| Alkali (AEL) | 3.789 | −594.3 |
| Solid Oxide (SOEC, ZrO2) | 5.500 | −5000.0 |
| Solid Oxide (SOEC, La0.8Sr0.2Ga0.8Mg0.2O3) | 4.420 | −3400.0 |