Patent ID: 8612062

Claim:
An energy management system including an energy supply device and an energy demand device to which energy is supplied from the energy supply device, the energy management system comprising: a first energy management device applied for the energy supply device; a second energy management device applied for the energy demand device; storage sections which are included in the first energy management device and the second energy management device, respectively, and in which a condition as to comply with an adjustment request of the energy supplied from the energy supply device to the energy demand device is stored; and calculating sections which are included in the first energy management device and the second energy management device, respectively, and which cooperate to execute a negotiation function calculating an energy adjustment amount satisfying the condition, wherein the negotiation function performs a bidirectional communication where one device of the first or second energy management devices provides a request condition concerning energy adjusting for another device of the first or second energy management devices and said another device provides a reward condition with respect to the request condition for said one device, and wherein the energy adjustment amount includes minimum and maximum energy adjustment amounts relating to the request condition and minimum and maximum values relating to the reward condition.