THE Mindanao grid was placed under red and yellow alert statuses on Wednesday, September 2, 2026, as available generation fell below projected peak demand, with the National Grid Corporation of the Philippines (NGCP) citing the unavailability of major coal-fired power plants, rising demand, and declining available generation in the region.
In its 2 p.m. update on September 2, NGCP reported an available capacity of 2,526 megawatts (MW) against a projected peak demand of 2,545 MW.
The grid was under yellow alert from 1 p.m. to 4 p.m. and from 5 p.m. to 8 p.m. Further, the NGCP raised the alert to red from noon to 1 p.m., from 4 p.m. to 5 p.m., and from 8 p.m. to 9 p.m. The latest figures showed a 19-MW gap between available capacity and projected peak demand.
NGCP attributed the extended alert declarations to the unavailability of Mindanao’s large coal plants, including GNPower Kauswagan (GNPK) Units 1 and 2 and Therma South Inc. Unit 2 (TSI 2). The grid operator also cited a significant increase in the region’s demand forecast and a decrease in available generation.
The latest alert followed a yellow alert declared over the Mindanao Grid on September 1. At that time, NGCP reported 2,555 MW of available capacity against a projected peak demand of 2,450 MW. The operator cited the unavailability of GNPK 2 and the forced outages of TSI 2 on August 29 and GNPK 1 on August 30.
The supply situation has been further affected by multiple generating units remaining unavailable.
According to the September 2 NGCP update, seven plants were on forced outage in September. Thirteen plants had been on forced outage since August, four since July, one since June, two since January, one since 2025, and one since 2024.
Seven other plants were operating at derated capacities. Combined, these outages and reduced-capacity operations accounted for 855.1 MW of unavailable generation.
The developments come amid recurring power-supply alerts in Mindanao and the Visayas in recent weeks.
NGCP has repeatedly cited the unavailability of large coal plants and other generating units as factors behind the tightening reserves.
On August 12, both the Visayas and Mindanao grids were again placed under alert statuses because several generating units remained unavailable.
The situation has also affected the ability of Mindanao to support the Visayas Grid through power transfers.
Recent NGCP advisories cited limited power imports from Mindanao as one of the factors contributing to supply constraints in the Visayas.
NGCP defines a red alert as a condition in which available power supply is insufficient to meet consumer demand and the transmission grid’s regulating requirement. A yellow alert, meanwhile, is declared when the operating margin is insufficient to meet the grid’s contingency requirement.
A yellow alert does not necessarily mean that power interruptions will occur, but it indicates that the grid has a thinner reserve and is more vulnerable to additional generation losses or unexpected increases in demand.
A red alert represents a more critical supply condition and may increase the possibility of controlled or rotational power interruptions.
The latest Mindanao alert comes as electricity demand continues to rise while several large generating units remain unavailable, placing additional pressure on the region’s already limited operating reserves. DEF
