Abstract: A backup-splice system for anti-islanding includes a wire cutter that severs a main service line within a main electrical panel of a residential unit to disconnect a microgrid from a power grid. Multiple splices provide an electrical connection on the main service line on each side of the wire cutter. A relay closes to enable the electrical connection along the main service line through the splices and opens to disconnect one or more distributed energy resources from the power grid. A controller opens the relay in response to detecting a power outage in the power grid, thereby preventing islanding of the microgrid. The backup-splice system is installed within the main electrical panel upstream of a main breaker and downstream of an electrical meter, avoiding modifications to utility-owned equipment outside the main electrical panel.

Abstract: In one implementation of a backup splice for anti-islanding, a system includes a wire cutter that severs an electrical wire (e.g., a main service line within a main electrical panel) within a microgrid of a residential unit, commercial unit, or other electrical system from the power grid. The system also includes multiple splices to provide an electrical connection on the electrical wire on each side of the wire cutter. A relay is configured to close to enable or complete the electrical connection along the electrical wire and open to disconnect one or more distributed energy resources (DERs) (e.g., a battery or solar panels) from the power grid. The system further includes a controller that opens the relay in response to detecting a power outage in the power grid, thereby preventing the islanding of the microgrid or the DER.