An operation management apparatus includes an air conditioning thermal load prediction unit configured to calculate an air conditioning thermal load predicted value indicating a predicted amount of heat required to adjust temperature to a pre-set temperature on a day-of-prediction, a power generation output prediction processing unit configured to calculate power generation output prediction data indicating a generated power obtained by a generator within the day-of-prediction, and an operation planning unit configured to prepare an air conditioning heat source operation plan, and determines a purchased power and the generated power using the power generation output prediction data to thereby prepare a power facility operation plan indicating a schedule of a power output from the purchased power source and the generator, so that the purchased power per predetermined time supplied from a purchased power source of a commercial power system becomes a target value.