Nigeria’s Independent System Operator (NISO) has traced Tuesday’s national grid collapse to a voltage disturbance at the Gombe transmission substation.
In a statement issued on Tuesday to update the public on repair and restoration efforts, the System Operator clarified that the incident did not amount to a total system collapse, contrary to reports by some media organisations. It described the event as the second grid disturbance recorded in 2026.
NISO explained that the disturbance originated at the Gombe transmission substation before spreading across other sections of the transmission network. The voltage fluctuation propagated rapidly, affecting several substations, including Jebba, Kainji and Ayede, before stabilisation measures took effect.
The incident caused some transmission lines and generating units to trip, resulting in a partial system collapse rather than a nationwide blackout. Power generation reportedly dropped to zero megawatts at about 11:00 a.m.
According to the operator, technical teams immediately deployed corrective actions, restoring the national grid within hours. Electricity supply across all affected areas has since returned to normal.
NISO added that Nigeria’s power grid has continued to experience recurring disturbances in recent years. In 2025, the grid collapsed several times, with the last incident recorded on 29 December, while Tuesday’s disturbance marks the second grid collapse in 2026.