PENGASSAN-Dangote Dispute Cuts Grid By 1,100MW — NISO
The Nigerian Independent System Operator (NISO) has confirmed that industrial actions within the gas supply chain, led by the Petroleum and Natural Gas Senior Staff Association of Nigeria (PENGASSAN), triggered widespread gas shortages that resulted in a reduction of power generation by more than 1,100 megawatts on Sunday.
According to NISO, available generation on the National Grid fell sharply from over 4,300MW in the early hours of September 28, 2025, to about 3,200MW at the lowest point.
In a statement released in the early hours of Tuesday, NISO stated that the development heightened pressure on the grid, prompting emergency measures to stabilise supply and avert a nationwide blackout.
To mitigate the crisis, the System Operator stated that it ramped up generation from major hydropower stations, injecting over 400MW to cushion the shortfall from gas-fired plants.
The agency stated further that it also implemented real-time load adjustments, frequency support measures, and selective load shedding to preserve operational security.
The agency reaffirmed its commitment to proactive grid management and best-in-class operational practices to guarantee a reliable electricity supply despite emerging challenges.
Advertisement
The statement reads: “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 4,300 MW in the early hours of Sunday, 28th September 2025, to about 3,200 MW at the lowest point.
£In response, the NISO promptly deployed contingency measures to preserve the stability, security, and reliability of the National Grid. Key interventions include:
“Hydropower Optimisation: Strategic ramp-ups from major hydro stations, contributing over 400 MW of additional output to cushion the shortfall from gas-fired plants.
“Generation Dispatch and Load Balancing: Real-time load adjustments to match available generation with system demand, while preventing a system frequency collapse.
Advertisement
“Voltage and Frequency Support: Continuous deployment of reactive power compensation and reserve monitoring to safeguard system integrity.
“Demand-Side Management: Selective load shedding, applied as a last resort, to avert a system-wide collapse and ensure fair power distribution.
“These timely actions enabled the NISO 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”.
