The National Grid Corp. of the Philippines (NGCP) declared the Luzon power grid under yellow alert for three hours on Thursday because of power-supply shortage.
A yellow alert means there are not enough reserves to cover the largest running generating unit at the time, but does not necessarily lead to power outages. For the Luzon grid, this is usually 647 megawatts (MW), or one unit of the Sual power plant. The yellow alert took effect from 1 to 3 p.m.
“Luzon grid is on yellow alert due to the unexpected shutdown and limited generation of some power plants,” the NGCP said.
Data had it that capacity stood at 10,740 MW, while peak demand was recorded at 9,654 MW, leaving reserves at 416 MW.
The thin reserve was brought about by the scheduled and unplanned shutdowns of power plants. The plants that went on forced shutdown are Makban Unit 5 (55 MW), SLPGC 1 (150 MW), SLGPC 2 (150 MW), Malaya 2 (320 MW) and San Gabriel (420 MW), Ilijan Block A (500 MW) and Makban Unit 2 (50 MW).
Also, there are plants whose capacity was derated. These are Calaca Units 1 and 2 at 230 MW and 220 MW, respectively, and Malaya 1 (150 MW).
Meanwhile, the plants that are on planned outage are Angat M Unit 3 (50 MW), San Roque Unit 3 (145 MW), Magat units 1&2 (180 MW) and Pagbilao Unit 1 (383 MW).
Angat will be online on July 30, while San Roque will resume on September 9. The Magat facilities will be online on April 17. Pagbilao, on the other hand, will resume on May 1.
In the evening of Thursday, the NGCP expected a “normal” power situation in Luzon.