A lawn mower includes an engine, an energy storage device, a motor/generator including an output shaft, an engine coupling, wherein, with the engine coupling disengaged, the motor/generator drives the output shaft, and with the engine coupling engaged, the engine or both the motor/generator and the engine drive the output shaft, a mower blade, a power take-off clutch, and a control unit configured to implement a first operating condition in which the engine coupling is disengaged, the engine is off, and the output shaft is driven by the motor/generator, and configured to implement a second operating condition in which the engine coupling is engaged, the engine is on, the output shaft is driven by the engine or both the motor/generator and the engine.