The result of specific energy consumption is revealed in Fig. 3d.
The value of ECTOC is not shown at 1.5 V as no chlorine is produced and TOC is totally removed by adsorption rather than electrochemical oxidation.
Besides, ECTOC is roughly similar at 2.0 V or 3.0 V.
However, the value of ECNaCl notably increases with the increasing potential.
Since more parasitic reactions will occur at higher applied potential, the energy consumption increases.
Not that ECNaCl is much lower than ECTOC.