Piezoelectric material generates a small electrical voltage, when its shape is deformed. This can be by as little as a 0.09% change, and can produce 12mAh worth of electricity at 230V (standard power output). It is important to note that the actual values of a piezoelectric material's volume or surface area do not change, as only the ratios of each axis (x, y and z) that are altered. E.g. a cuboid with 20 meters cubed volume can have the normal dimensions 1 meter by 2 meters by 10 meters, and the deformed dimensions 2 meters by 2.5 meters by 4 meters; the volume would remain the same, .