The resumption of red and yellow alerts in Luzon and Visayas due to insufficiency in power supply has led to a temporary power interruption that affected thousands of customers.

After just two days of normalcy, the National Grid Corporation of the Philippines (NGCP) has placed Luzon and the Visayas under red and yellow alerts as a total of 49 power units were either on forced outage or operating at limited capacity, slashing a total of 2,123.3 megawatts (MW) of capacity from both grids.

The Luzon grid was initially placed under yellow alert from 1:00 p.m. to 5:00 p.m. and from 6:00 to 10:00 p.m.

But later today, the NGCP revised its advisory to declare a red alert from 3:00 to 4:00 p.m. and from 6:00 p.m.

Thus, a yellow alert was moved to between 4:00 to 6:00 p.m. and 10:00 p.m. to 12:00 midnight.

As of 5:00 p.m., the Luzon grid has an available capacity of 12,832 MW and a peak demand of 12,671 MW.

In the Visayas, a yellow alert was also raised from 1:00 p.m. to 8:00 p.m. The grid reportedly has an available supply of 2,742 MW, while peak demand is projected to reach 2,571 MW.

The power alerts were issued for five consecutive days from Tuesday to Saturday last week before being lifted on Sunday and Monday.

Service interruptions

As a result, the NGCP reported that La Union, Tarlac, and Camarines Sur experienced up to 15 minutes of power interruption, while some parts of Isabela and Pampanga encountered longer outages.

Meanwhile, the Manila Electric Co. (Meralco), the country's largest power distributor, confirmed that an automatic load dropping triggered a service interruption that lasted for about 20 minutes affecting about 200,000 customers in some parts of Metro Manila, Pampanga, Bulacan, Laguna, and Quezon Province.

As the country's power supply remains unstable, Meralco and the Department of Energy (DOE) have jointly called for more private companies to implement a so-called Interruptible Load Program (ILP) to help manage the system.

The program allows customers with high electricity usage to operate their own generator sets during periods of power shortages in the electrical grid.

Although the program contributes to managing the electrical system, customers are responsible for covering the fuel costs associated with running these alternative power sources.

"We call for your support and cooperation for the country's objective of having continuous power supply by participating in the ILP and being part of the solution to the power supply challenges," Director of the Electric Power Industry Management Bureau Irma Exconde said.

Meanwhile, Meralco's vice president and head for enterprise and national government Ma. Cecilia Domingo said: "The active participation of ILP participants in the Meralco franchise area in recent days is worth highlighting as it has greatly helped relieve pressure from the power grid, sparing thousands of small businesses and households from rotating power interruptions."

Meralco has been implementing its power distribution reliability program 27 times since 2014 within its franchise area.

In the past week alone, the program effectively prevented power interruptions, benefiting approximately 1.9 million households.

Currently, 239 service accounts are enrolled in the ILP managed by Meralco, with an aggregate capacity of approximately 530 MW.