- The combined impact of forced plant outages and de-rating in the capacity of some facilities, primarily the hydro plants, shaved off capacity from Luzon grid by 2,684MW leading to the brownouts in the franchise area of Meralco and the grid-wide declaration of yellow alert.
More than 500,000 Meralco customers suffer brownouts
Luzon grid on yellow alert due to plant outages
BY MYRNA M. VELASCO – Jul 11, 2023 03:11 PM
from Manila Bulletin
AT A GLANCE
The forced outages suffered by at least five major electric generating facilities plunged Luzon grid into a new round of yellow alert as some 1,897 megawatts (MW) of capacity were dropped from the system, according to the National Grid Corporation of the Philippines (NGCP).
Apart from the grid-wide yellow alert, power utility giant Manila Electric Company (Meralco) similarly reported brief power interruptions or brownouts within its franchise area affecting more than 500,000 customers.
The “yellow alert condition” in the main power grid of Luzon had been raised by NGCP from 2:00pm to 4:00pm on Tuesday, July 11, although other advisories placed it at 1:00pm to 4:00pm.
“In response to NGCP’s declaration of yellow alert, we activated the interruptible load program (ILP) and are currently securing de-loading commitments from our big load customers,” Meralco stressed.
The ILP seeks big-ticket customers to switch on their own generating facilities so they can help pare demand as the grid is afflicted with tight supply predicaments.
NGCP advised media that the yellow alert condition in the grid was lifted as of 4:00pm.
Meanwhile, the NGCP advisory specified that the plants on unscheduled shutdowns had been the: 150MW Unit 1 of South Luzon Power Generation Corp.; 600MW Block A and 600MW Block B of the Ilijan plant; 266MW San Lorenzo plant module 50 and 264MW San Lorenzo facility module 60; then the La Farge power facility with 6MW capacity and a power plant with 11MW capacity.
Several plants were also conveyed to be on de-rated state or reduced generation capacity, including Calaca-2 plant; Sual unit 1; Masinloc plant unit-3; Magat hydroelectric plant; and San Roque hydropower facility. These shaved off capacity availability by 787MW.
If reckoned, the aggregate loss of supply due to plant outages and capacity de-rating hovered at 2,684MW, and this triggered the insufficiency of power reserves warranted in the country’s biggest grid.
As explained by Meralco, it was prompted to enforce automatic load dropping (ALD) or service interruptions for eight minutes until service restoration at 11:06am – that was due to load drop of 396MW from its network.
Meralco indicated that the areas affected by momentary brownouts had been those in Bulacan, Rizal, Cavite, Laguna and Quezon as well as customers in various parts of Metro Manila, including Caloocan City, Malabon, Navotas, Makati, Mandaluyong, Manila, Paranaque, Pasig, Pasay and Quezon City.
In a statement to the media, the Department of Energy affirmed that “the scheduled contingency reserve is already below the level of the highest unit online,” and that clearly signals distress leading to the declaration of yellow alert in the grid.
The DOE emphasized that it is still “coordinating with San Lorenzo and other stakeholders for the cause of the tripping.”
