Ionic thrusters are powered by a phenomenon known as electrohydrodynamic thrust, or “ionic wind.” This wind is created when a current of electricity is passed between two electrodes- one thinner than the other.

If both the space between the electrodes and the voltage applied between the electrodes are sufficiently large, then the “ionic wind” can become a full-blown thrust, with enough power to propel an object forward without the help of a motor or fuel.