‘PHP 169-M RISK’: Power interruptions reveal fragile Visayas grid, ICE warns

By Francis Allan L. Angelo

Recurring power interruptions in Iloilo City during June 2026 were not ordinary local outages but evidence of a Visayas Grid operating with too little margin, the Institute of Contemporary Economics (ICE) said in a new analytical report.

The Iloilo City-based think tank examined the issue in “Manual Load Dropping and the Fragility of the Philippine Power System,” dated June 2026, which traced why the city experienced repeated curtailment and what those events cost a metropolitan economy.

From June 2 to June 19, 2026, Iloilo City recorded at least seven publicly posted MORE Power advisories for Manual Load Dropping (MLD) directed by the National Grid Corporation of the Philippines (NGCP), the report said.

Over the same period, the Visayas Grid was repeatedly placed under Yellow Alert, with one confirmed Red Alert on June 10.

The report defined Manual Load Dropping as controlled demand reduction ordered by the grid operator to protect grid security when available supply, reserves, or deliverability are insufficient to safely support full demand.

Consumers experienced the interruptions locally through distribution feeders, but the decision to reduce load came from NGCP as grid operator, while MORE Power implemented the reduction within its franchise area, the report said.

A grid with too little margin

The June 10 Red Alert offered the clearest view of the system’s condition, with the Visayas Grid carrying only 2,429 megawatts of available capacity against projected peak demand of 2,421 megawatts, leaving an apparent margin of just 8 megawatts.

For a grid serving more than 2,400 megawatts of demand, that margin was functionally negligible, the report said. NGCP also cited reduced power imports from Mindanao through the high-voltage direct current interconnection as a factor in the Red Alert.

On other documented alert days, apparent margins remained narrow relative to system size, at 130 megawatts on June 2, 160 megawatts on June 3, 133 megawatts during the earlier June 10 Yellow Alert, 118 megawatts on June 18, and 47 megawatts on June 19, according to the report.

The grid also carried large volumes of unavailable or derated capacity, reported at 996.4 megawatts on June 2, 985.5 megawatts on June 3, about 890.4 megawatts during the June 10 Red Alert, 947.8 megawatts on June 16, and 964.4 megawatts on June 18.

On June 19, NGCP reported 13 plants on forced outage or derated status, the report said.

Counting the economic exposure

ICE estimated the economic exposure from recurring curtailment using Iloilo City’s 2024 gross domestic product (GDP) at current prices of PHP 210.97 billion.

That figure is equivalent to roughly PHP 578 million in output per day, or about PHP 24.1 million per hour, the report said.

Under a conservative scenario, ICE assumed that a typical MLD event affects 25% to 35% of economically active load for 1.5 to 2.0 hours, placing roughly PHP 9.0 million to PHP 16.9 million in output at risk per event, with a base estimate of PHP 12.7 million.

At 10 events in one month, the indicative exposure reaches about PHP 127 million, within a plausible range of PHP 90 million to PHP 169 million.

The report stressed that these figures are not direct losses, noting that some activity is deferred, some firms use backup power, and some output is recovered after service resumes. It described the estimate as the value of activity placed at risk rather than output permanently destroyed.

A June 18, 2026, Primelectric letter to the Department of Energy (DOE) provided an operational cross-check, the report said.

Covering MORE Power, Negros Power, and Bohol Light, the letter reported MLD incidents from May 13, 2026, onward, with a combined 645,400 customers affected and 940,848 kilowatt-hours of energy loss across the three franchise areas.

For MORE Power alone, the submitted table reported 135,364 affected customers and 340,990 kilowatt-hours of energy loss.

The letter was addressed to Energy Secretary Sharon Garin, with a copy furnished to Energy Regulatory Commission (ERC) Chairperson Francis Saturnino C. Juan.

A convergence of causes

The report attributed the June pattern to a convergence of factors rather than a single cause, citing unavailable Visayas generation, thin operating reserves, deliverability constraints into Panay, and reduced inter-grid support from Mindanao.

The Mindanao earthquake reduced grid flexibility but did not create the Visayas problem, the report said, noting that the Visayas Grid was already operating with thin margins.

On June 10, the Mindanao Grid was itself under Yellow Alert, with available capacity of 2,731 megawatts against projected peak demand of 2,611 megawatts, leaving 120 megawatts of apparent headroom, while NGCP reported 1,259.9 megawatts of unavailable Mindanao generation.

The report also pointed to the late-afternoon and early-evening timing of many events. Citing DOE 2025 Power Statistics, it noted that the Visayas Grid had 701 megawatts of installed solar capacity, or 17.1% of installed capacity, and 569 megawatts of dependable solar capacity, or 16.3% of dependable capacity, with solar supplying 922,176 megawatt-hours, or 5.8% of grid generation, in 2025.

The problem was not solar itself but insufficient planning for the hours when solar output declines and demand remains high, the report said, citing ERC Chairperson Francis Saturnino C. Juan’s May 2026 remarks on a “flexibility shortage” after sunset.

ICE said Panay’s vulnerabilities were already visible, citing earlier ICE work estimating that Panay recorded the fastest power-demand growth among components of the Visayas Grid, at a compounded annual growth rate of 18.5% between 2020 and 2023.

That earlier work estimated Panay’s 2023 peak demand at 481 megawatts, against installed generating capacity of 821 megawatts and dependable capacity of 714 megawatts, with about 100 megawatts of Panay and Guimaras-linked capacity coming from intermittent renewable sources that cannot be treated as firm reserve capacity during evening peaks, cloudy periods, or system stress.

The Cebu–Negros–Panay backbone improved the island’s position but did not convert it into a fully resilient power system, the report said.

The report flagged a possible security-limited reduction in transfer capability along the Leyte–Cebu 230-kilovolt corridor as an unconfirmed industry-source lead requiring formal confirmation, noting that if a reported reduction from a 440-megawatt transfer reference to roughly 70% of that level is accurate, the implied reduction of about 132 megawatts would be system-significant in a grid that reached an 8-megawatt margin on June 10.

Where accountability begins

Ultimate sector accountability begins with the DOE, which the Electric Power Industry Reform Act (EPIRA) assigns the planning, integration, reliability, and reserve-adequacy role for the electric power industry, the report said.

NGCP must answer for grid operation and transmission deliverability, ERC for regulatory timeliness, generators for plant availability, distribution utilities for local implementation, and Congress for the statutory architecture, according to the report.

ICE recommended binding reserve adequacy, event-level disclosure, a review of transmission constraints, stronger Panay deliverability, whole-chain modernization, a stronger DOE-led system-integration role, and completion of EPIRA’s institutional architecture.

A resilient grid uses curtailment as a last resort, the report concluded, while a fragile one begins to rely on it as part of normal operating practice.

ICE described Iloilo’s recent experience not only as a local power-interruption story but as a national reliability warning seen from a city whose economy can no longer afford a power system built with so little margin.