The Cebu Electricity Rights Advocates (CERA) said recent grid disturbances in Luzon and the Visayas highlight how energy reliability issues are increasingly tied not just to insufficient power generation, but also to structural and operational weaknesses in the transmission network managed by National Grid Corporation of the Philippines (NGCP).
According to CERA, transmission bottlenecks, limited grid redundancy, and failures involving critical transmission assets have become major contributors to widespread outages and instability in the power system.
“We must recognize that many recent outages are increasingly linked to transmission vulnerabilities under NGCP,” said Nathaniel Chua, lead convenor of CERA.
“While public attention often focuses on reserve margins and power generation during peak demand periods, grid stability also depends heavily on the reliability and resilience of the transmission backbone operated by NGCP.”
Disturbance
CERA noted that recent grid disturbances in Luzon and the Visayas in May 2026 demonstrated how failures in key transmission assets can trigger broader instability across the system, even when sufficient generation capacity exists elsewhere.
In particular, the tripping of major 500kV NGCP transmission lines — including the Ilijan-Dasmarinas and Ilijan-Tayabas lines — significantly reduced the grid’s ability to transmit more than 1,300 megawatts of power.
The incident prompted several distribution utilities (DUs) to implement Automatic Load Dropping (ALD) measures to help prevent a wider grid collapse, despite available power generation in other parts of the system.
Load dropping
CERA also raised concerns over vulnerabilities within the Visayas grid.
NGCP this month implemented Manual Load Dropping (MLD) affecting 18 electric cooperatives following unplanned generation outages and concerns over the loading capacity of the NGCP-operated Daanbantayan-Tabango 230kV transmission line.
The group said the incident underscored the urgent need for greater transmission redundancy and stronger grid resilience to absorb operational disruptions and prevent cascading outages.
“To break the cycle of recurring outages, the country’s energy strategy must move beyond a purely supply-focused approach and adopt a resilience-first framework that prioritizes transmission reliability alongside additional power generation,” Chua said.
“The Philippines cannot achieve long-term energy stability by simply building more power plants. The transmission system must also be strengthened to ensure electricity can be delivered reliably to homes, businesses, and communities nationwide.”
Yellow alert
The Visayas grid has been in yellow alert in the past two weeks, mainly due to the unavailability of the several power plants including the 14 that had been on forced outage since May 2026.
As of May 27, available capacity of 2,509 megawatts barely met the demand of 2,333 MW.
A yellow alert is issued when the operating margin is insufficient to meet the transmission grid’s contingency requirement.
In the NGCP advisory, a yellow alert was placed from 2 p.m. to 10 p.m. on May 26 mainly due to the outage of Panay Energy Development Corp. Unit 2.
It added that at least 960.55 MW of capacity were unavailable to the grid, with 14 power plants on forced outage since May 2026, one since March 2026, three since 2025, two since 2024, two since 2023, and one since 2021. Meanwhile, 15 other plants were operating at derated capacities. —Ed: Corrie S. Narisma
Contributor
