A device control apparatus connectable to a demand response system that executes demand response by controlling the amount of power supplied from an electric power system to a device, the device control apparatus comprising: a detection unit that detects a parameter that indicates a state of the electric power system; a first communication interface that communicates with a device that receives power supplied from the electric power system; a second communication interface that receives, via a communication network, a demand response signal from a server that monitors the state of the electric power system; and a control circuit that controls the device via the first communication interface, wherein the demand response signal contains either one of first information that indicates an instruction for increasing an amount of power supplied from the electric power system to the device and second information that indicates an instruction for decreasing the amount of power supplied from the electric power system to the device, and the control circuit is further configured to determine whether control of the device is performed in accordance with the demand response signal based on the first information or the second information contained in the received demand response signal and the detected parameter, wherein when the detected parameter indicates a state in which the amount of power supplied from the electric power system to the device has to be increased and the demand response signal contains the first information, or when the detected parameter indicates a state in which the amount of power supplied from the electric power system to the device has to be decreased and the demand response signal contains the second information, then the control circuit performs control of the device in accordance with the demand response signal. a detection unit that detects a parameter that indicates a state of the electric power system; a first communication interface that communicates with a device that receives power supplied from the electric power system; a second communication interface that receives, via a communication network, a demand response signal from a server that monitors the state of the electric power system; and a control circuit that controls the device via the first communication interface, wherein the demand response signal contains either one of first information that indicates an instruction for increasing an amount of power supplied from the electric power system to the device and second information that indicates an instruction for decreasing the amount of power supplied from the electric power system to the device, and the control circuit is further configured to determine whether control of the device is performed in accordance with the demand response signal based on the first information or the second information contained in the received demand response signal and the detected parameter, wherein when the detected parameter indicates a state in which the amount of power supplied from the electric power system to the device has to be increased and the demand response signal contains the first information, or when the detected parameter indicates a state in which the amount of power supplied from the electric power system to the device has to be decreased and the demand response signal contains the second information, then the control circuit performs control of the device in accordance with the demand response signal.