Abstract: The present invention is a system, apparatus and method for an overall power management system for powering one or more power consuming devices used in vehicles and assisting with the management of auxiliary energy storage, while ensuring that the starter battery remains charged for engine starting. The present invention may be an integrated system, and related apparatus, for managing a plurality on-board power consuming devices and power sources. The present invention may be utilized to reduce the need for engine idling to maintain power to one or more power consuming devices. The present invention may include: a monitoring device to monitor the power consumption of one or more power consuming devices and/or the charge of one or more auxiliary energy storage devices and an a starter battery; and a control device to ensure that the power consuming devices are powered while a vehicle is in a stationary position.