Abstract: Methods and systems for using distributed energy resources in an electric network are disclosed. In one example, a system for use in controlling an electric network is described. The system includes a plurality of sensors coupled to a plurality of locations in an electric network to monitor operating conditions of the electric network at the plurality of locations. At least one state estimator is communicatively coupled to the plurality of sensors and configured to output substantially real-time estimations of a state of the electric network based, at least in part, on the monitored operating conditions. A management system is coupled to receive the substantially real-time estimations from the at least one state estimator. The management system is configured to control operation of the electric network based, at least in part, on the substantially real-time estimations to facilitate minimizing transmission losses in the electric network.