Whole PH under yellow alert; Luzon, Visayas grids also under red alert

MANILA – The National Grid Corp. of the Philippines (NGCP) has placed the Mindanao grid under yellow alert, and the Luzon and Visayas grids under red and yellow alert.

In its advisory Wednesday, the NGCP said the Mindanao grid is under yellow alert from 10 a.m. to 4 p.m., as nine power plants went offline and five more plants are running on a derated capacity.

A total of 673.98 megawatts (MW) were unavailable to the grid, causing the declaration of a yellow alert in the southern part of the country.

“A yellow alert is issued when the operating margin is insufficient to meet the transmission grid’s contingency requirement,” the NGCP said.

Peak demand in the Mindanao grid on Wednesday is projected at 2,761 MW, with available power capacity at 2,614 MW, leaving an operating margin of only 147

MW.

Yellow and red alerts were also declared in the Luzon and Visayas grids.

The Luzon grid is placed under yellow alert from 1 p.m. to 3 p.m. and 4 p.m. to 10 p.m. and under red alert from 3 p.m. to 4 p.m.

On the other hand, the Visayas grid has a longer red alert period from noon to 5 p.m. and 6 p.m. to 8 p.m., and yellow alert from 10 a.m. to noon, 5 p.m. to 6 p.m., and 8 p.m. to 9 p.m.

“The reduced capacity exported by Mindanao to Visayas also aggravated the power situation in Visayas,” NGCP explained.

Under red alert, power interruptions may be exper ienced.

Meanwhile, the NGCP said it monitored a system disturbance at 3:30 p.m. on Tuesday that triggered the activation of its protection system and affected four power plants, which aggravated the already thin power supply.

These power plants are the 316-MW

GNPower 1, the 150-MW Sem-Calaca Power Corp. (SCPC) 1, the 150-MW SCPC 3, and the 60-MW Limay Block B.

Except for GNPower 1, the three power plants went back online as early as 3:43 p.m. on Tuesday.

The NGCP said it is still investigating the root cause of the system disturbance. (PNA)