A disc pump includes a pump body having a cavity for containing a fluid. The disc pump also includes an actuator adapted to hold an electrostatic charge to cause an oscillatory motion at a drive frequency. The disc pump further includes a conductive plate positioned to face the actuator outside of the cavity and adapted to provide an electric field of reversible polarity, the conductive plate being electrically associated with the actuator to cause the actuator to oscillate at the drive frequency in response to reversing the polarity of the electric field. The disc pump further includes a valve disposed in at least one of a first aperture and a second aperture in the pump body. The oscillation of the actuator at the drive frequency causes fluid flow through the first aperture and the second aperture when in use.