Visayas grid under red, yellow alerts on September 7

Brownouts may occur in the Visayas as the grid was placed under red and yellow alerts on Monday, September 7, due to thin power reserves, the National Grid Corporation of the Philippines (NGCP) said.

In an advisory, the NGCP said the red alert would be raised over the grid from 6 p.m. to 7 p.m. The grid would also be under yellow alert from 3 p.m. to 6 p.m. and from 7 p.m. to 9 p.m.

The grid operator cited the following factors behind the red and yellow alert declarations:

• Unavailability of the Visayas' large coal plants TVI 1 in Toledo City, Cebu, and PEDC 3 in La Paz, Iloilo;
• De-rated capacity of THVI 2 in Toledo City, Cebu, at 146.2 megawatts due to a main steam problem; and
• Limited power imports from Mindanao.

The NGCP said eight plants were on forced outage as of September, five had been on forced outage since August, one since July, two since June, seven since May, three since 2025, two since 2024, two since 2023, and one since 2021.

Meanwhile, 15 plants were operating below their full power capacity.

The outages and reduced capacity left 818.9 MW of power unavailable to the Visayas grid, the NGCP said.

A red alert is issued when the power supply is insufficient to meet consumer demand and the transmission grid's regulating requirement.

A yellow alert, meanwhile, is issued when the operating margin is insufficient to meet the transmission grid's contingency requirement.— MCG, GMA News