A method is provided of determining total electric power consumption of a managed IT network including network devices having a management-addressable address. An autodiscovery tool is run to discover the network devices of the managed IT network. Management requests are directed to the management-addressable addresses of the network devices to obtain the electric power consumption values of the network devices. The electric power consumption values returned by the network devices are centrally collected, and the total electric power consumption of the managed IT network is calculated by adding the electric power consumption values of the network devices.