A method for managing power consumption within a facility includes receiving a request to reduce a total level of power consumption within the facility by a predetermined measure (S23). A plurality of operating parameters indicative of how much power is being consumed by each of a plurality of facility systems is received(S21). A corresponding cost associated with a marginal power reduction is determined for each of the plurality of facility systems using the received plurality of operating parameters (S24). A power allocation to the facility system of the plurality of facility systems that is determined to have a lowest marginal cost of power reduction is incrementally reduced (S25). The steps of determining a corresponding cost and incrementally reducing power are repeated until the total level of power consumption within the facility has been reduced by the predetermined measure.