A system for managing consumption of power supplied by an electric utility to power consuming devices includes at least one client device and a server. Each client device operates at least partially responsive to control messages received from the server and controls operation of one or more controllable devices. Each controllable device selectively enables and disables a flow of power to one or more of the consuming devices. The server stores information, on a per client device basis, relating to power consumed by the consuming devices. When a power reduction is requested by the utility, the server selects, based on client device information stored in the database, at least one client device to which to issue a power reduction message that indicates at least one of an amount of power to be reduced and an identification of a controllable device to be instructed to disable a flow of power.