An apparatus includes a controlled field alternator or utility source of electrical power, a conversion device, and a controller. The conversion device includes a first power input associated with a first power source, a second power input associated with a second power source, and circuitry configured to perform a first conversion of power from a first format from the first power source to a second format for charging the second power source and perform a second conversion of power from the second format for the second power source to a third format for supplying a load.