Abstract: An in-line generator fits between the engine and transmission of a conventional motor vehicle. The in-line generator comprises an externally cooled housing having a first end that is mounted to the engine in place of the transmission. The transmission is secured to the housing second end in the same manner as the transmission would normally be secured to the engine. One end of a rotor is fastened to the engine crankshaft. A coupling is attached to the rotor second end and to the transmission input shaft. When the engine is operated, the rotor rotates to cooperate with a stator in the housing to produce electric power. The rotor also transmits torque to the transmission to propel the motor vehicle. The coupling includes a flex plate that accommodates thermal expansion of the rotor and other generator parts. The in-line generator can be removed from the vehicle and the transmission resecured to the engine as in a normal vehicle should the in-line generator require repair.