Forced outage of Kalayaan power plant affects Luzon grid


The unexpected shutdown of units 1 and 2 at the Kalayan hydropower plant in Laguna on Tuesday afternoon triggered rotational brownouts in certain Luzon provinces.

The National Grid Corporation of the Philippines (NGCP) announced the implementation of manual load dropping, or rotational brownouts, which affected consumers served by Benguet Electric Cooperative, parts of Ilocos Sur Electric Cooperative, as well as Nueva Ecija Electric Cooperatives 1 and 2, and Aurora Electric Cooperative.

For Manila Electric Company (MERALCO), rotational brownouts had not been scheduled as of 5:00 pm, but the red alert for the Luzon grid had been extended until 11:00 pm on Tuesday.

NGCP also declared that the red alert status was prolonged due to the outage of two additional plants, Kalayaan 1 and 2, resulting in rotational power interruptions affecting parts of northern Luzon.

It is worth noting that anticipated brownouts in certain areas did not materialize yesterday due to sustained supply during peak demand hours from 2:00 to 3:00 pm. 

Despite this, red alert hours on power supply were maintained from 6:00 to 9:00 pm, attributed to the forced outages of 21 electric generating units in the Luzon grid, which also included the sudden downtime of two of Kalayaan power plants.

The systems operator (SO) also noted that 19 power plants went on forced outages, while three others were operating at derated capacities, resulting in a total of 2,117.3 megawatts unavailable to the grid.

A red alert is issued by NGCP when reserves in the system are projected to fall below 4.0 percent against peak demand.

Meanwhile, yellow alert periods, which meant there were insufficient power reserves, were experienced in Luzon and Visayas during specific hours of the day.

In the Visayas grid, 12 power plants experienced forced outages, while five others operated at derated capacities, totaling 676.5 MW unavailable to the grid.

Major plants experiencing forced outages included those of Masinloc 1, Santa Rita plant module 40, Binga 1 and 4, Ambuklao 1 and 2, Bakun 1 and 2, Maris 1 and 2, National Irrigation Administration unit, Bineng plant, Irisan, Pagbilao units 1 and 2, VS Gripal plant, and BT 2020 generating units, resulting in a total loss of 1,811.3 megawatts.