A communication apparatus comprises a first communication unit configured to receive, from an external server, an output suppression message instructing output suppression of a dispersed power source; and a second communication unit configured to perform communication of a predetermined message having a predetermined format with a power management apparatus that manages power of an equipment installed in a consumer's facility. The output suppression of the dispersed power source is performed in accordance with the output suppression message by a conversion apparatus that converts DC power output from the dispersed power source to AC power. The predetermined format includes an information element capable of storing at least one of first information and second information, the first information being related to a communication status with the conversion apparatus, the second information being related to an acquisition status of the output suppression message. The second communication unit is configured to transmit, to the power management apparatus, the predetermined message including at least one of the first information and the second information as an information element.