El Niño and pumped hydro storage system

After a prolonged La Niña from 2020 to 2025, we are back to El Niño phase this year until at least 2027. The current one is called a “Super El Nino” with temperature anomaly or deviation from the mean of 2.2 Celsius. This is a misnomer because there were other previous El Niño with similar high temperature anomaly: 2016 El Niño and 1998 El Niño with 2.3 Celsius, 1983 El Niño with 2.1 Celsius.

In between those periods are mild El Niño and/or “Big La Niña” with temperature anomaly of -2.0 C in 1989, prolonged La Niña in 1999-2002, 2008-2012 with short El Niño in 2010.

Our “problem” in the Philippines and the tropics is too much water, too much rain and flood every year but we lack water impounding systems like natural lakes, man-made lakes and large dams which have many purposes – reduce flashflood downstream, use the stored water for power generation, irrigation, potable water, eco-tourism, etc.

Pumped storage hydro and CBK

Last week, I joined the energy beat from different newspapers and radio/TV outlets in Manila plus Laguna-based media in a lecture, “Power101: Role of Pumped Hydro in the Philippines Energy Grid” held at the Caliraya-Botocan-Kalayaan (CBK) Pumped Storage Hydro (PSH) Power Complex in Kalayaan, Laguna.

The speakers were Engr. Ariel Fronda, chief of the DOE’s Hydropower and Ocean Management Division and Engr. Bernardo Manosca, facility head of Clearnergy9 which manages the CBK plant owned by the Thunder Consortium that won the bidding of the CBK last year. The consortium is led by Aboitiz Power (AP) plus Sumitomo Corp. and Japan Power.

PSH is an old but beautiful technology. When electricity demand and prices are high, it releases water from the upper reservoir to a hydro plant below to produce electricity, and when power demand and prices are low, it takes water from the lower reservoir and pump it to the upper reservoir and store water there. This way, the PSH system helps flatten the price curve while helping to avoid blackout when demand is high.

CBK is the first and only PSH in the Philippines with total capacity of 797 MW (Kalayaan  735 MW + Caliraya 39 MW + Botocan 23 MW). The upper reservoir is Caliraya Lake, the lower is Laguna Lake.

Engr. Fronda discussed the valuable role of hydro plants, both baseload and peaking or mid-merit like PSH, the high capex needed to develop hydro plants, average of P200 million per MW.

Engr. Manosca led in giving us a tour of the two of four units of Kalayaan plant, 183.5 MW each. The turbines can quickly ramp up and produce electricity within 10 minutes and help stabilize the Luzon grid. Beautiful.

Not far from the four units of Kalayaan plant is a large switchyard by the National Grid Corp. of the Philippines (NGCP).

Fengning PHS in Hebei province, China

Two years ago on a visit in China, I saw not only the numerous road tunnels from Beijing to Hebei province – smooth roads, well-lighted and have internet even in the middle of a five-km tunnel or longer. I also saw and rode their high speed train running at 350 kph (vs Europe’s max 300 kph, Japan shinkansen up to 320 kph), Beijing subway system, etc.

The Fengning hydro is the world’s largest PHS until today, 3,600 MW capacity (360 MW x 12 units). Huge, wide lower and upper reservoir. The control system is 500 meters below the surface and has internet below. The State Grid Corp. of China (SGCC) owns it as one of its large ancillary service facilities.

China has the largest power generation in the world, 10,575 terawatt-hours (TWH) in 2025, larger than the US’ 4,772 TWH, and 82 times larger than the Philippines’ 129 TWH. SGCC’s ability to transmit and stabilize such huge power supply is excellent. The NGCP is lucky to have SGCC as its technical partner.

Hydro plants of Mindanao and need for privatization

The government, through the Power Sector Assets and Liabilities Management Corp. (PSALM), still owns seven big hydro plants in Mindanao. The six Agus hydro plants with total capacity of 747 MW, plus Pulangi hydro (run of river) with 255 MW. All commissioned between 1971-1986.

PSALM and the DOF should privatize those Mindanao hydro plants soon, for two big reasons. One, generate revenues without new taxes and help address our huge outstanding public debt of P19.61 trillion as of August 2026, that requires huge interest payment of P772 billion in January-September 2026 alone or average of P2.83 billion a day.

And two, help improve the efficiency of those hydro plants so they can expand their power generation. Consider these three big hydro plants in Luzon privatized by PSALM around 2007-2008, their commissioning year and provincial location in parenthesis:

Magat hydro (1983, Isabela) has installed capacity of 360 MW, became 388 MW after privatization. Binga hydro (1960, Benguet) has capacity of 100 MW, became 140 MW after privatization. And Ambuklao hydro (1956, Benguet) has capacity of 75 MW, became 112.5 MW after privatization. All three were purchased by SNAP (SN Power of Norway and AP)  which introduced rehabilitation and modernization of the three hydro plants.

The president and CEO of SNAP when those outrageous improvement in efficiency happened was Manny Rubio, now president and CEO of Meralco PowerGen Corp. (MGEN). When Manny was promoted to head AP overall in 2015, Joseph Yu succeeded him as president of SNAP. Both have retired from AP upon mandatory retirement age and joined MGEN.

When PSALM would privatize those seven hydro plants in Mindanao, I hope that either AP or MGEN will get them because they have the most skilled and experienced people to run and modernize even very old hydro plants.