COMMUNICATION METHOD BETWEEN ELECTRIC VEHICLE, SUPPLY EQUIPMENT, AND POWER GRID OPERATION SERVER

A method of communicating between an electric vehicle, a supply equipment, and a power grid includes transmitting, by an electric vehicle communication controller of the electric vehicle, a discharge schedule including an amount of energy discharge, a discharge start time, and a discharge finish time to a supply equipment communication controller of the supply equipment or a power grid communication controller of the power grid operation server, and receiving a discharge cost calculated according to the discharge schedule from the supply equipment communication controller or the power grid communication controller, wherein the discharge cost including an additional calculation cost, in response to a sum of the amount of energy discharge of the electric vehicle and an amount of energy discharge of another electric vehicle being greater than or equal to a reference energy discharge amount.