2026 Event Schedule

Distributed energy resources (DERs) have been empowering customers to achieve independence and sustainability while reducing their costs of energy. However, the large integration of DERs has been a major factor in disrupting the way distribution systems have been planned, operated, protected, and controlled for decades. While many solutions have been developed, tailored, and improved over time based on the traditional assumptions of radiality and unidirectional power flow, the growing penetration of DERs requires reevaluating their response under these new operating conditions. For instance, power outage restoration decisions have been automated to properly perform fault location, isolation, and service restoration (FLISR) within seconds from an unplanned outage event occurrence, improving power delivery’s reliability, quality, and customer satisfaction. As their primary objective, FLISR solutions aim to maximize restored customers and to achieve that optimal decisions are made based on pre-event demand levels. With the increasing presence of DERs, demand levels have become more volatile and unpredictable, which can significantly change from the moment decisions are made to the moment they are implemented. IEEE 1547-2018, IEEE Standard for Interconnection and Interoperability of Distributed Energy Resources with Associated Electric Power Systems Interfaces, establishes criteria and requirements for interconnection of DERs so that operators know which range of responses to expect. Under IEEE 1547-2018, a DER is required to disconnect during an outage, but its reconnection after re-energization can vary from seconds to minutes. The difference in demand from the pre-event to full reconnection can be enough to place the restored system into unreliable and unsafe operating conditions, such as overloading and low voltage. Moreover, reducing the burden that this puts on the grid operations workforce will be the biggest benefit to managing these impacts. This paper interprets the IEEE 1547 standard’s criteria and requirements with regard to distribution system power outage restoration, where the influence of the DER response in automatic restoration decisions is explored. The discussion is expanded to cover potential solutions to mitigate this influence, such as overload mitigation and how metering location and capabilities may improve system awareness before, during, and after restoration, and how such visibility can benefit the restoration problem.