Luzon grid hit anew with rotating brownouts


By Myrna Velasco

As power reserves continue to decline, several areas in the Luzon grid were hit with a new round of roughly one-hour duration of power interruptions manifesting the very precarious state of electricity supply in the country’s major power grid.

According to the Manila Electric Company (Meralco), manual load dropping (MLD) or rotating brownouts started at 1:19 p.m. in the circuits of Malolos and Tabang towns in Bulacan province.

(MANILA BULLETIN) National Grid Corporation of the Philippines (MANILA BULLETIN)

At 2:00 p.m., the power interruptions spread to other parts of Bulacan including Hagonoy, Malolos City, Plaridel, Balagtas, Meycauayan, and Marilao; then extended further to Metro Manila primarily in the cities of Caloocan, Malabon, and Navotas.

The rotating brownouts ensued following the declaration of ‘red alert’ state for Luzon grid by system operator National Grid Corporation of the Philippines (NGCP) due to negative reserves – covering the periods from 10:01 a.m. to 11:00 a.m.; then from 1:00 p.m. to 3:00 p.m.

Several intervals had likewise been declared to be on “yellow alert” state, inferring tight supply condition with very little room for reserves if additional power plants will be taken out from the system due to technical glitches.

Three power plants with aggregate installed capacity of 765 megawatts have been on forced outages – namely units 1 and 2 of South Luzon Thermal Energy Corp; unit 1 of Mariveles GNPower facility; and unit 1 of SMC Consolidated Power Corp’s Limay plant.

Many of the hydropower facilities are also experiencing de-rated capacities, taking off some 290MW from the system. The hydro plants with de-rated generation, according to the Department of Energy (DOE), had been the Angat, Ambuklao-Binga, Pantabangan, and San Roque plants.

As of 1:00 p.m. on Tuesday, June 18, NGCP data showed that peak demand in Luzon grid hit as high 11,006MW while system capacity was just at 11,301MW – leaving them a very marginal reserve of 295MW which is not even enough to plug the system’s need for contingency reserve.

Visayas grid’s power situation was similarly edgy Tuesday with just 16MW of reserve – given that peak demand hovered at 2,144MW versus available capacity of 2,160MW.

With the weather just hovering at 34 to 35 degrees Tuesday compared to the previous sweltering ones at 36 to 38 degrees, the power system no longer held despite Luzon grid’s reliance on additional capacity from the interruptible load program (ILP) or requiring entities with generating sets to utilize them so grid demand can be eased.

The biggest problem of the Duterte administration starting this year throughout its term will be the ‘insecurity of power supply’ in the country – which does not also go well with the infrastructure development program being pursued by the government.