POWER CONTROL SYSTEM AND METHOD, AND CONTROL DEVICE

In a power control system (1), a control device (100) acquires at least one of information about an external environment (result or predicted temperature) of a facility (800) and information on a parameter associated with power consumption (production plan) in an internal environment of the facility (800) and calculates a correlation between these pieces of information and actual consumed power. The control device (100) predicts consumed power of the facility (800) on the basis the correlation that is calculated and information such as predicted temperature and determines an upper limit set value of power supplied from an electrical grid to the facility (800) on the basis of a result of the prediction. The control device (100) supplies power charged in a storage battery (500) to the facility (800) when the consumed power of the facility (800) exceeds the upper limit set value. Thereby, power is able to be used in a facility while a peak of power demand is further leveled and the peak of power demand is controlled so as not to exceed maximum power that is able to be supplied by an electric power supplier.