In a mobile communication network, technologies are provided for determining power consumption of a communication site. An OSS system receives power consumption information of one or more devices and traffic volume information from a communication site. Then, the OSS determines power consumption of one or more virtue devices of the communication site, which are listed on a pre-configured device list according to power of the virtue devices, traffic volume information of the communication site, or both, wherein the a virtue device is not capable of monitoring power consumption, reporting power consumption, or both. Then the OSS determines power consumption of the communication site according to the power consumption information of the one or more devices received from the communication site and the power consumption of the virtual device in the communication site.