A machine tool with a generator for generating electrical power is disclosed. The generator has a rotor and a stator. A coil and a magnet are arranged on the stator. The rotor is capable of moving relative to the stator and has a first region and a second region. The rotor is configured in such a way that, during a movement of the rotor relative to the stator, a magnetic flux in the coil is changed due to differences between the first and second regions in terms of their magnetic permeability and/or in terms of their geometric configuration, and an electrical voltage is induced.