An interface apparatus for a stochastic high-voltage source employs a mandatory series path containing an electrochemical cell with a nonlinear current-voltage curve. The cell operates as a capacitor below a threshold voltage ranging from 0.8 to 2.0 volts and autonomously switches to a faradaic electrolysis mode above this threshold. This clamps overvoltages by converting energy into chemical fuel with efficiency exceeding fifty percent while damping the source via a cascade stabilizing effect. The path excludes parallel dissipative clamps. The cell has a double-layer capacitance of at least 0.5 farads and exhibits an impedance drop of at least ten times within one millisecond upon transitioning. A controller modulates path impedance and verifies operation via correlated voltage changes and gas flow without high-frequency noise. The apparatus is applicable to diverse electrolyzer types providing universal productive clamping for atmospheric electricity, electrostatic discharge, electromagnetic interference, corona, and triboelectric sources.