A self-recharging electric generator system in communication with an external system, where the external system includes a power source external to the self-recharging electric generator system, and the self-recharging electric generator system includes at least one electric motor configured to receive power from the power source of the external system, at least one generator configured to produce power to be supplied to the external system, and to the at least one electric motor, at least one sensing device configured to be connected with an onboard battery system of the external system, to sense a charge status of the onboard battery system, and a switch device electrically coupled with the at least one sensing device and configured to switch from the power source of the external system to the at least one generator as the source for supplying power to the at least one electric motor.