Quezon City Congressman Marvin Rillo (District IV) expressed concern over the weekend over the lack of rainfall due to the intensifying El Niño weather condition that might disrupt the operations of hydropower facilities and undermine Luzon's already tight supply of electricity in the months ahead.

"We would like to urge the House committee on energy to look into the potential adverse impact of prolonged below normal rainfall conditions on hydroelectric power plants in Luzon," Rillo said in a statement.

"Grid-connected, dam-type impounding hydro, pumped hydro, and run-of-river power plants currently supply around 13.9 percent of Luzon's dependable generating capacity," Rillo pointed out.

Hydroelectric power plants contribute an aggregate of 2,416 megawatts to the Luzon grid, according to Rillo, a member of the House committee on energy.

Hydropower relies on the constantly recharging system of the water cycle to produce electricity.

Last month, the country's two largest power distributors — Manila Electric Co. and Aboitiz Power Corp. — warned that even without the El Niño threat, Luzon's power supply would remain tight in 2024, with no baseload capacity added to the grid while demand is expected to continue growing.

In an advisory issued 6 December, the Philippine Atmospheric, Geophysical and Astronomical Services Administration said that the "strong El Niño has further intensified, nearing its peak in the coming months."

By the end of December, Metro Manila will likely experience a "dry condition" while Cavite is bound to reel from a "drought," according to Pagasa's El Niño Advisory No. 6.

Meanwhile, Pagasasaid at least 18 provinces in Luzon are likely to experience a "dry spell" by the end of December: Benguet, Ifugao, Kalinga, Apayao, Mountain Province, Ilocos Sur, La Union, Pangasinan, Cagayan, Isabela, Nueva Vizcaya, Quirino, Bulacan, Nueva Ecija, Pampanga, Tarlac, Aurora and Palawan.

Along with Metro Manila, five other provinces in Luzon are likely to experience a dry condition by the end of December: Abra, Ilocos Norte, Bataan, Zambales, and Occidental Mindoro, Pagasa said.

A dry condition means two consecutive months of below normal rainfall condition, or 21 percent to 60 percent reduction from average rainfall.

A dry spell is defined as three consecutive months of below normal rainfall condition, or 21 percent to 60 percent reduction from average rainfall.

Drought means three consecutive months of "way below normal rainfall condition," or greater than 60 percent reduction from average rainfall.

Based on Department of Energy data, Rillo said the Luzon grid-connected operating hydroelectric power plants and their corresponding dependable generating capacities include:

Kalayaan PSPP in Kalayaan, Laguna (720 MW); San Roque in San Manuel, Pangasinan (404 MW); Magat in Ramon, Isabela (345.6 MW); Angat Main in Norzagaray, Bulacan (200 MW); Casecnan (NIA) in Pantabangan, Nueva Ecija (150 MW); Binga in Itogon, Benguet (138 MW); Pantabangan in Pantabangan, Nueva Ecija (120 MW); Ambuklao in Bokud, Benguet (105 MW); Bakun AC in Alilem, Ilocos Sur (59.4 MW); Caliraya in Lumban, Laguna (35 MW); Botocan in Majayjay, Laguna (22 MW); Angat Aux in Norzagaray, Bulacan (18 MW); Sabangan in Sabangan, Mt. Province (15 MW); and Masiway in Pantabangan, Nueva Ecija (12 MW).

In its December outlook, Pagasa said none of the provinces in the Visayas and Mindanao are at risk of a dry condition, a dry spell, or a drought.