During disasters, widespread power outages occur, and after power is restored, power shortages arise, making it impossible to maintain power supply to evacuation centers, medical facilities, and communication equipment. [Solution] The present invention provides a power supply
maintenance system that enables the maintenance of power supply both before and during supply by identifying the required amount of power corresponding to the supply period or the remaining period of the supply period based on the load to be supplied, identifying the amount of power that can be supplied by multiple power sources, excluding or limiting power sources that do not meet the required amount of power from candidates, determining the configuration of a power source or group of power sources that will satisfy the required amount of
power over the supply period, and changing the configuration if there is a possibility that the supply maintenance conditions will not be met during supply. Furthermore, this invention is applicable to various uses, including power supply to evacuation centers, medical facilities, and communication equipment during disasters.