The Nigerian Independent System Operator (NISO) has pinpointed the cause of Tuesday's national grid disturbance to a voltage fault at the Gombe transmission substation. In a detailed statement, NISO clarified that the incident did not constitute a total system collapse, as some media reports had suggested, but was instead classified as a partial system collapse.
Incident Details and Classification
According to NISO, this event marks the second grid disturbance recorded in 2026. The disturbance originated at the Gombe transmission substation before rapidly spreading to other parts of the transmission network. This propagation led to the tripping of several transmission lines and generating units, causing power generation to drop to zero megawatts at approximately 11:00 am.
The national grid has been fully restored, and electricity supply across the affected areas has since returned to normal, NISO confirmed. The operator emphasized that the incident only impacted a portion of the national grid, thereby not qualifying as a total collapse. The statement added, The event was accompanied by the tripping of some transmission lines and generating units, resulting in a partial system collapse.
Spread and Impact of the Disturbance
NISO explained that the voltage disturbance quickly propagated across the transmission network, affecting multiple substations beyond Gombe. Specifically, the disturbance spread to the Jebba and Kainji transmission substations, while the Ayede transmission substation also experienced disruptions before stabilization measures were effectively implemented.
Restoration Efforts and Technical Response
Restoration efforts commenced shortly after the incident and were completed within hours, thanks to immediate corrective actions by technical teams. These teams worked diligently to stabilize the grid and restore normal operations, minimizing the duration of the disruption for consumers.
Historical Context of Grid Disturbances
Nigeria's power grid has faced recurrent disturbances in recent years. In 2025, the grid collapsed multiple times, with the last incident occurring on December 29. Tuesday's disturbance represents the second grid-related incident in 2026, highlighting ongoing challenges in maintaining grid stability and reliability.
This incident underscores the critical need for robust infrastructure and proactive maintenance to prevent future disturbances and ensure consistent power supply across the nation.
