Abstract: The present invention discloses a smart power supply system for electrical appliances, using a rechargeable power storage device, a logic controller, and a learning controller, to control and minimize electricity consumption from mains power during standby. In standby mode, when only a small amount of electrical power is needed, energy from the power storage device is used and mains power is disconnected unless the power storage device requires a recharge. A logic controller senses the appliance's operating state, using it to determine when power should be supplied from mains power or the power storage device. A learning controller monitors and stores historical characteristics of the power storage device's charge and discharge cycles, using them to automatically calculate new recharge cycle parameters to minimize mains power consumption. An external input and output module enable users, computers and electronic devices to interact and program the learning controller.