An energy source for use with an electrosurgical system is disclosed. In one embodiment, the energy source includes a power supply, one or more capacitors coupled to the power supply, and a switching component coupled to the one or more capacitors. The switching component is configured to output pulses of a biphasic waveform. The pulses are capable of treating undesired tissue by inducing a change in voltage potential across cell membranes of a plurality of cells in the undesired tissue to promote non-thermal cell death in the plurality of cells. The pulses are also capable of treating the undesired tissue with no or minimal muscle contractions in patient tissue within reach of the biphasic waveform during treatment of the undesired tissue.