Abstract: A high-power, high-repetition-rate spark gap switch having metal-hydride electrodes is provided The spark gap switch is configured with a trigger and two electrodes fabricated with metal hydrides. The hydride metals may be selected from a variety of alloys including iron, nickel, magnesium, and palladium based alloys. Use of these alloys for fabrication of the electrodes permits hydrogen to be absorbed into the electrode material at a density approximately that of liquid hydrogen. During operation of the switch, the increasing temperature causes hydrogen to be desorbed into cavity surrounding the switch. Whereas the increasing temperature lowers the breakdown voltage of the switch, the increasing pressure raises the breakdown voltage. The result is the switch operates at a constant breakdown voltage independent of temperature.