An apparatus for installation within a tire for a vehicle includes a flexible arm and a power generating element coupled to the flexible arm for generating electrical energy. One end of the flexible arm is coupled to a rim of the tire. The opposing end of the flexible arm is configured to be in contact with the inside tread surface of the tire. The flexible arm is capable of deformation in response to a variability of distance between the rim and the inside tread surface during rolling movement of the tire, and the power generating element generates the electrical energy in response to deformation of the flexible arm. The apparatus may be combined with a tire pressure sensor module as a system so as to provide electrical energy for powering the tire pressure sensor module.