Note also that, CIP controls the applied electrode potential in the electrode bulk and the applied potential does not depend on the presence of surface charge due to e.g. the protonation/deprotonation of semiconductor surfaces. While the surface charge does not pose a fundamental problem for CIP, it has to be screened by the space charge layer after which the bulk region can begin. Finally, while the CIP formalism can be applied to the simulation of semiconductor electrodes in equilibrium, modelling out-of-equilibrium conditions would require an extension to compute species-specific quasi-Fermi levels or to otherwise account for the species-dependency of the electrochemical potentials.