The Nigerian Independent System Operator (NISO) has confirmed that a labor dispute between Dangote Refinery and the Petroleum and Natural Gas Senior Staff Association of Nigeria (PENGASSAN) is causing a significant gas shortage, leading to a drop of over 1,100 megawatts (MW) in national power generation.
okay.ng reports that power output on the National Grid plunged sharply from above 4,300MW early on September 28, 2025, to a low of roughly 3,200MW.
NISO issued a statement on Tuesday morning, describing the severe pressure placed on the grid and detailing the emergency interventions employed to stabilize the situation and avoid a nationwide blackout. These measures included increasing generation from key hydropower stations, contributing an additional 400MW to compensate for lost capacity from gas-powered plants.
The operator also carried out real-time load modifications, frequency support, and selective load shedding to preserve system security. The statement affirmed: “The Nigerian Independent System Operator 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 within the gas supply chain.”
It added, “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.” To mitigate this, NISO deployed contingency actions including hydropower optimization, generation dispatch adjustments, voltage and frequency support, and demand-side management via selective load shedding.
Despite the unprecedented challenge, the agency reiterated its dedication to best-in-class grid management, promising a steady, reliable electricity supply for the nation.
The strike followed the dismissal of over 800 Nigerian workers at Dangote Petroleum Refinery, which led PENGASSAN to call for a nationwide work stoppage beginning at midnight on Monday, September 29, 2025. Workers in field locations also began a continuous prayer vigil at 6:00 a.m. on Sunday, September 28.
As a result, operations at major oil and gas regulatory bodies and industry players have been paralyzed. Federal Government efforts to resolve the crisis on Monday failed to yield any breakthrough after hours of negotiations.