POWER supply has been restored nationwide after the national electricity grid suffered another disruption on Monday, leading to a partial system collapse, the Nigerian Independent System Operator (NISO) confirmed in the late hours of Monday.
The operator said the disturbance occurred at exactly 2:01 p.m. on Monday, December 29, 2025, interrupting electricity supply across several parts of the country.
Power generation had earlier peaked at about 4,800 megawatts (MW) yesteday before plunging to 139MW by 3 p.m., according to industry data.
In a statement issued Monday night, NISO said the disturbance triggered the tripping of multiple power plants and key 330-kilovolt transmission lines, worsening the already fragile state of the grid.
“The Nigerian Independent System Operator wishes to inform the general public and relevant stakeholders that the National Grid experienced a system disturbance at 14:01 hours on Monday, 29 December 2025, that led to a partial collapse,” the statement said.
“Preliminary reports indicate that the disturbance involved the tripping of several generating units and critical 330kV transmission lines, resulting in a widespread impact on electricity supply across parts of the country.”
The incident occured amid ongoing gas supply constraints following the vandalisation of the Escravos–Lagos gas pipeline on December 10, which significantly reduced gas available to thermal power plants and deepened power supply challenges nationwide.
NISO noted that the gas shortages further weakened the grid, making it increasingly vulnerable to system disturbances.
Despite the setback, the operator said the Delta generation complex successfully isolated itself from the grid and continued operating in island mode at the 132kV sub-transmission level. This allowed uninterrupted power supply to the Oghara, Amukpe, Benin and Efunrun substations, with four units at the Delta Thermal Power Station delivering a combined 114MW.
The system operator added that it activated emergency procedures immediately after the disturbance and coordinated grid recovery efforts through the National Control Centre in Osogbo.
NISO confirmed that power supply had been fully restored nationwide and grid stability normalised after hours of coordinated intervention.
“Supply has been fully restored to all parts of the country and the system stability normalised,” the operator said, adding that investigations were ongoing to determine the precise cause and sequence of events.
It assured that corrective measures would be implemented to minimise the risk of future grid collapses.
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“NISO reassures Nigerians of its continued commitment to proactive grid management and the application of best operational practices to ensure the stability and reliability of the National Grid.”
Grid collapse report
Economy Post earlier reported that the national grid collapsed on Monday, as power supply hit near-zero levels across the country. As of mid-afternoon, power distribution data showed that power flow to consumers had almost completely slumped.
Load figures released at 4:44 pm on December 29, 2025, showed that just two electricity distribution companies were receiving supply. While Ibadan Electricity Distribution Company had 30 megawatts (MW), Abuja Electricity Distribution Company received miserably-low 20 MW. Other electricity distribution companies got zero MWs around that time.
This is the fourth time the national grid has collapsed this year, with the last reported on September 10.
In 2024, the national grid suffered 12 collapses, with the latest incident occuring on December 11. The number represented nine times more than what was seen in 2023.
Several factors are responsible for the frequent power grid failure in Nigeria, including infrastructure decay, poor maintenance, poor funding and vandalism.
The Transmission Company of Nigeria (TCN) recorded 131 cases of infrastructure vandalism in 2025. Managing Director and Chief Executive Officer of TCN, Mr Abdulaziz, disclosed this in his end-of-year message to staff, partners, and stakeholders earlier this month.
“From January to November 2025 alone, the company recorded 131 vandalism incidents across its network. Management is working closely with the Office of the National Security Adviser, security agencies, and community vigilante groups to curb this menace,” he said, adding that TCN would continue sensitisation campaigns and community engagement to safeguard critical infrastructure.
He stressed this year had presented its unique set of challenges, from evolving regulatory landscapes to the persistent issues of infrastructure vandalisation and liquidity constraints affecting the TCN operations, noting, however, that the agency would overcome the obstacles.
