MANILA, Philippines – The National Grid Corporation of the Philippines (NGCP) lifted on Saturday morning, May 16 the red and yellow alerts over Luzon and Visayas. 

“Barring any unexpected increase in demand or additional unplanned outages of power facilities, the power situation for this weekend is expected to remain stable,” the NGCP said in a 10:30 am advisory. 

As of 6 am on Saturday, Luzon had a surplus capacity of 3,692 megawatts (MW) while Visayas had a thin surplus of 429 MW. The surplus in Luzon, however, enables power to be exported from the Luzon grid to support the Visayas grid.

Luzon and Visayas had been on red and yellow alerts for the past three days due to the tripping of two transmission lines while peak demand remained high due to the high summer temperatures.

The heat index in Metro Manila, for instance, was from 42 degrees to 44 degrees Celsius from Wednesday to Friday, the same range expected this weekend. 

On Saturday, the NGCP said three power plants went back to full capacity, adding a total of 1,1510 MW to the Luzon grid and creating a power surplus.

In addition, the NGCP noted that there is “typically lower system demand during weekends.” 

For Luzon, the available generating capacity was at 15,799 MW with peak demand at 12,107 MW, translating to a positive margin of 3,692 MW.

For Visayas, available capacity was pegged at 2,768 MW while demand was at 2,339 MW, leading to an excess of 429 MW.

For Mindanao, the NGCP said the island was under “normal conditions” with available capacity at 3,323 MW and peak demand at 2,300 MW, creating a margin of 1,023 MW.

The NGCP issues a red alert status when the power supply is not enough to meet consumer demand.

A yellow alert is issued when the operating margin is not enough to meet the grid’s contingency requirements.

The NGCP is a privately owned corporation which operates and maintains the Philippines’ power grid with State Grid Corp. of China as the minority and technical partner. 

The Department of Energy had directed the NGCP to submit an incident report on the red and yellow alert declarations that affected Luzon and Visyas from May 12 to 14 which it said “placed millions of Filipino [electricity] consumers at risk over a three-day period.” 

It specifically asked the NGCP to explain the “back-to-back tripping” of the 500 kilovolt (kV) transmission lines at the Ilijan power complex in Batangas on May 13, plus the subsequent tripping of the 500 kV Ilijan-Tayabas transmission lines. These cut off supply from major generation plants and prompted the red and yellow alerts in Luzon and Visayas beginning Wednesday, May 13. – Rappler.com