The recent wave of rolling brownouts has intensified concerns over the Philippines’ fragile power system, with an economist warning that outdated transmission infrastructure is now emerging as a major threat to energy security.

According to Philippine Institute for Development Studies (PIDS) senior research fellow Adoracion Navarro, the country’s electricity problem is no longer limited to power generation shortages but has evolved into a broader issue involving the reliability and resilience of the national grid.

“The rolling brownouts yesterday underscored that the Philippines’ power vulnerability is not just a matter of insufficient generation capacity but, increasingly, a grid resilience problem,” Navarro said during a webinar organized by the research institution on 14 May.

Navarro pointed to widening gaps between electricity demand and transmission development. Citing findings from her study on transmission sector reforms, she said electricity consumption in the country expanded by around 140 percent between 2003 and 2024, while transmission lines grew by only 11 percent over the same period.

The imbalance, she said, has resulted in heavier congestion across the grid, rising reliability concerns, and greater exposure to power interruptions.

The economist also highlighted delays in critical transmission projects being undertaken by National Grid Corporation of the Philippines. Of the 258 planned projects, only 75 have reportedly been completed so far.

She said weak regulatory oversight, right-of-way issues, and poor coordination among government agencies have slowed the expansion of the transmission network and prevented infrastructure from keeping pace with growing consumer demand.

Navarro added that underinvestment in transmission facilities has worsened the country’s energy insecurity, particularly during periods of peak demand such as the summer months.

“This underinvestment in transmission contributed to the ongoing energy insecurity in the Philippines. The problems due to underinvestment were compounded by other concerns such as inadequate ancillary services, which made the power system unreliable especially during peak hours in the summer months,” she said.

Beyond infrastructure delays, Navarro also raised concerns over grid reliability, limited transmission capacity, and the lack of adequate connections in renewable energy zones. She likewise pointed to governance and national security issues linked to foreign equity participation in critical power infrastructure.

To address these concerns, Navarro urged policymakers to accelerate reforms in rate-setting, permitting, right-of-way acquisition, and inter-agency coordination to ensure faster project completion and improve support for renewable energy integration.

She also called for stronger accountability mechanisms for delayed projects and reforms that would align investment incentives with long-term public interest goals.