Institute for Climate and Sustainable Cities
REACTIVE

QUEZON CITY, May 14 2026 –– The latest rotating blackouts across Luzon and Visayas underscore the systemic risks created by concentrating generation and transmission infrastructure in a limited number of large facilities and critical corridors. From the forecasted available capacity in Luzon of 16,975 MW reported by the NGCP earlier in the day, system availability dropped to 12,447 MW, reflecting how concentration of critical assets can lead to an immediate tightening of power supply conditions.

The cascading tripping on May 13 of 500 kV Dasmariñas-Ilijan transmission line at 4:48AM and  500 kV Tayabas-Ilijan transmission line at 6:39AM has triggered the disconnection of nearly 2,500 MW of capacity, including the Ilijan 1 and 2 plants (1,200 MW) and EERI Units 1, 2, and 3 (1,262.1 MW), both of which are LNG facilities. Even though the transmission lines were restored online later that same day, the disconnected power plants were not able to immediately resume generation, prolonging the supply shortfall and triggering the rotating blackouts. 

As of this writing, these plants have yet to be re-commissioned and returned to service. Until they are brought back online, the capacity deficit will persist, and further grid alerts remain likely. According to the National Grid Corporation of the Philippines (NGCP), the Luzon and Visayas grids will be placed under red and yellow alert again today.

On April 16, these same power plants also experienced simultaneous forced shutdowns due to issues involving the LNG terminal supplying their feedstock requirements. Both incidents highlight the vulnerability of an energy system heavily reliant on centralized infrastructure. Whether through a shared LNG terminal or a critical transmission corridor, disruptions in these critical nodes can quickly cascade into broader system-wide supply shortages and grid instability.

These recent events show that the available electricity supply can drop significantly when more than one major power plant or key facility goes offline at the same time. This raises an important consideration: as the power system continues to rely on large centralized infrastructure—such as LNG facilities—the level of reserves or backup needed to maintain reliability may need to increase, with possible implications on electricity costs.

“Reserves today are sized based on the largest power plant connected to the grid. But if a single shared facility, such as an LNG terminal or critical transmission corridor, can affect multiple plants at once, then that shared infrastructure should arguably become the benchmark for reserve requirements,” said ICSC Chief Data Scientist Engr. Jephraim Manansala.

In addition to issues encountered in the transmission facilities, forced outages of coal-fired plants further exacerbated supply tightness. Among those reported were the forced outage of Masinloc Unit 3 (335MW), which tripped at 6:35 AM of the same day, and Mariveles Power Generation Corporation Unit 4 (150MW), which had already been on forced outage since May 10, adding to the overall capacity deficit. Based on the Grid Operating and Maintenance Program (GOMP), no plant should be on outage during the second quarter of the year — yet these unplanned outages persisted, exposing the gap between scheduled maintenance assumptions and real-world plant reliability.

To break the cycle of grid alerts and rotating blackouts, the Philippines must move towards a more decentralized, diversified, and flexible power system, where the outage of no single facility can put the entire grid at risk.

Decentralized and diversified — given the country’s archipelagic geography and vulnerability to extreme weather, power generation should also be geographically spread out and technologically varied. A more decentralized and diversified approach enables communities to depend less on a handful of large plants, strengthening local reliability and self-sufficiency while reducing the risk of supply disruptions caused by outages, disasters, or other physical shocks. Expanding the share of indigenous renewable energy — such as geothermal, hydropower, solar, and wind, backed by energy storage systems — will be central to this shift to further diversify the country’s power mix.

Flexible – given that grid alerts persist only during specific hours of the day, this indicates that additional power capacity is needed only during those particular periods. Inflexible baseload power plants will not resolve the issues we are encountering today, as they are not designed to ramp up and down quickly during these windows. What is needed are technologies that can flexibly respond to fluctuations in supply and demand and recover quickly from disruptions. These include battery storage systems, pumped-hydro storage facilities, and other fast-ramping generation capacity.

A system built on diversified, distributed, and flexible resources minimizes single points of failure. More importantly, it offers a more stable foundation for affordable, reliable, and secure electricity for all Filipinos.

ABOUT
The Institute for Climate and Sustainable Cities is a Philippine-based non-governmental organization that advances climate, energy, and low-carbon solutions to enable fair and climate-resilient development at the national and international levels.

CONTACTS
Sanaf Marcelo, ICSC: media@icsc.ngo, +63 968 886 3466, +63 917 149 5649
Pauline Alvarez, ICSC: media@icsc.ngo, +63 999 338 9414

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