The Visayas power grid was placed under red and yellow alert statuses on Wednesday, July 8, due to insufficient supply and multiple plant outages, the National Grid Corporation of the Philippines (NGCP) said.

In an advisory issued at 2:50 p.m., the NGCP said the grid would be under red alert from 3 p.m. to 9 p.m., indicating that the available power supply is not enough to meet consumer demand and required reserves.

Yellow alert status was set from 1 p.m. to 3 p.m. and again from 9 p.m. to 11 p.m., signaling thin operating reserves in the system.

Data from the NGCP showed available capacity at 2,397 megawatts, below the projected peak demand of 2,492 megawatts.

The grid operator said 10 power plants were on forced outage in July alone, with additional plants offline since previous months and years. A total of 1,092.8 megawatts is currently unavailable to the grid due to outages and derated capacities, with 14 plants running below normal output.

The NGCP cited two key incidents that triggered the red alert declaration: the tripping of the Iloilo-PEDC 138-kilovolt Line 3 at 1:32 p.m., which led to the isolation of a generating unit, and the emergency shutdown of another plant at 2:06 p.m. due to a possible boiler tube leak.

A red alert is declared when supply cannot meet demand and the grid’s regulating requirements, while a yellow alert indicates an insufficient operating margin to cover potential contingencies.