The last total system collapse recorded was on 20 July 2022, an official said.
The Transmission Company of Nigeria (TCN) on Thursday said the national grid restoration nationwide is in progress and has reached advanced stages.
The TCN General Manager Public Affairs, Ndidi Mbah, in a statement, said the restoration has led to power supply now available in the West, North Central, South, East, and a large portion of the Northern parts of the country.
She explained that the power supply restoration was sequel to the total grid collapse, which occurred at 12.35 a.m., this morning, causing outages nationwide, after over 421 days of consistent grid stability.
"In the course of the grid restoration, the process initially suffered a setback; this does not amount to another collapse. In the course of any grid restoration process, challenges may be encountered.
"This happened today while the grid restoration was in progress, but it was promptly addressed," she said.
"It would be recalled that the last total system collapse recorded was on 20th July 2022, from then to the 13th of September, 2023, ( 421 days), the system had been stable in spite of the challenges posed by zero spinning reserve and lack of adequate System Control and Data Acquisition (SCADA) essential to a strong and stable grid, among others
"TCN has been able to maintain 421 days of grid stability because it developed and deployed in-house stop-gap measures and tools that it has continued to use to manage the nation's grid, ensuring its stability," she added.
Meanwhile, Mrs Mbah said the collapse which occurred after a fire incident on Kanji/Jebba 330kV line 2 is being investigated, with the view to forestalling future occurrences and invariably further strengthening the grid.
"The incident, notwithstanding, TCN is determined to continue to do its best to ensure grid stability," she said.
Background
Nigerians were on Thursday morning thrown into darkness after the national grid system collapsed.
The system is operated by the Transmission Company of Nigeria (TCN) from Osogbo, Osun State.
Some of the nation's Distribution Companies confirmed that the grid collapsed in the early hours of Thursday, as most of their feeders are out.
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The latest collapse is coming weeks after the TCN announced that the country's power grid had maintained uninterrupted stability for over 400 consecutive days.
The TCN had in August said the Nigerian power grid has recorded an unparalleled period of stability in the history of the power sector, operating without any major disruptions or systems collapse for an impressive span of 400 consecutive days and counting.
"This milestone signifies a remarkable advancement in the nation's efforts at strengthening its power infrastructure and ensuring a reliable and dependable electricity supply to distribution load centres for onward distribution to electricity customers nationwide," the company said in a statement.
In recent years, the power sector has experienced many broad challenges related to electricity policy enforcement, regulatory uncertainty, gas supply, transmission system constraints, and major power sector planning shortfalls.
In 2022 alone, the country's national grid collapsed eight times.
