The Nigerian Independent System Operator (NISO) has announced a drop in power generation from over 4,300MW recorded in the early hours of Sunday, 28 September 2025, to about 3,200MW at the lowest point.
The operator stated that industrial action by the Petroleum and Natural Gas Senior Staff Association of Nigeria (PENGASSAN) within the gas supply chain triggered widespread gas shortages, leading to a generation shortfall on the national grid.
“The Nigerian Independent System Operator (NISO) wishes to notify the public of recent major generation shortfalls on the national grid, caused by industrial actions of the Petroleum and Natural Gas Senior Staff Association of Nigeria (PENGASSAN) within the gas supply chain.
“These disruptions triggered widespread gas shortages, reducing available generation from over 4,300MW in the early hours of Sunday, 28 September 2025, to about 3,200MW at the lowest point.
Read Also: PENGASSAN strike continues, as mediation talk ends in deadlock
“In response, the NISO promptly deployed contingency measures to preserve the stability, security, and reliability of the national grid. Key interventions include hydropower optimisation, generation dispatch and load balancing, and voltage and frequency support,” NISO said in a statement issued to journalists.
The operator added that it applied selective load shedding as a last resort to avert a system-wide collapse and ensure fair power distribution.
These timely actions, it said, enabled the NISO National Control Centre (NCC) to minimise the impact of the labour-induced gas shortages, sustain operational security, and maintain supply to critical loads, thereby averting a nationwide blackout.
“The system operator reaffirms its commitment to proactive grid management, operational excellence, and the application of best-in-class practices to guarantee a secure and reliable electricity supply for the nation,” it added.
PENGASSAN commenced its strike action on Monday despite calls for calm from the federal government.
