A smart electric temperature-controlled system connected to a vehicle, such as a vehicle-transported refrigeration system, includes a power management system and an energy storage module. The power management system and energy storage module can manage power delivered to the temperature-controlled system components by monitoring temperatures and voltages (and possibly other factors) and by delivering power as a function of the things monitored. In a typical implementation the power management system and an energy storage module can supply power to a vehicle-transported refrigeration system when the vehicle is stopped and/or power from the vehicle electrical system is electrically isolated or otherwise unavailable.