A method for managing power of a smart appliance , comprising: acquiring, from the smart appliance , by an Energy Management System, EMS, for managing power of the smart appliance at home over a home network, terminal information including information about functions supported by the smart appliance , power consumption information of the smart appliance , and a power management method of the smart appliance , wherein the power management method of the smart appliance is set to any one of a manual mode for manually controlling the power by interaction with a user and an automatic mode for automatically controlling a function of the smart appliance ; monitoring , by the EMS, power of the smart appliance and transmitting the monitoring results to an energy service provider ; controlling , by the EMS, upon receiving a power reduction command from the energy service provider , the power of the smart appliance based on the acquired terminal information, and received user preference information associated with a control of power of each of a plurality of smart appliances, and wherein controlling the power of the smart appliance by the EMS further comprises: selecting the smart appliance and a terminal function to be controlled in the smart appliance based on the acquired terminal information and the previously stored user preference information; sending , if the power management method is set to the manual mode, a power control command to the smart appliance and receiving power control results from the smart appliance ; and controlling , if the power management method is set to the automatic mode, the selected terminal function of the smart appliance . acquiring, from the smart appliance , by an Energy Management System, EMS, for managing power of the smart appliance at home over a home network, terminal information including information about functions supported by the smart appliance , power consumption information of the smart appliance , and a power management method of the smart appliance , wherein the power management method of the smart appliance is set to any one of a manual mode for manually controlling the power by interaction with a user and an automatic mode for automatically controlling a function of the smart appliance ; monitoring , by the EMS, power of the smart appliance and transmitting the monitoring results to an energy service provider ; controlling , by the EMS, upon receiving a power reduction command from the energy service provider , the power of the smart appliance based on the acquired terminal information, and received user preference information associated with a control of power of each of a plurality of smart appliances, and wherein controlling the power of the smart appliance by the EMS further comprises: selecting the smart appliance and a terminal function to be controlled in the smart appliance based on the acquired terminal information and the previously stored user preference information; sending , if the power management method is set to the manual mode, a power control command to the smart appliance and receiving power control results from the smart appliance ; and controlling , if the power management method is set to the automatic mode, the selected terminal function of the smart appliance . selecting the smart appliance and a terminal function to be controlled in the smart appliance based on the acquired terminal information and the previously stored user preference information; sending , if the power management method is set to the manual mode, a power control command to the smart appliance and receiving power control results from the smart appliance ; and controlling , if the power management method is set to the automatic mode, the selected terminal function of the smart appliance . <EOS>