THE National Grid Corp. of the Philippines (NGCP) has called for improved energy resource planning following the outages on Tuesday at multiple power plants on Panay Island.

“The unscheduled maintenance shutdowns of the largest power plants in Panay Island were the primary cause of the power interruption. We emphasize the need for improved planning to ensure sufficient generation per island, with a well-balanced mix of fuels and technology,” NGCP said in a statement on Wednesday.

On Tuesday, the NGCP issued a yellow alert for the Visayas grid after multiple power plants tripped, including units of Panay Energy Development Corp. and Palm Concepcion Power Corp. (PCPC).

Due to the plant outages, some 452 megawatts (MW) were unavailable to the grid.

As of 5 p.m. on Wednesday, about 203 MW of power is being produced on Panay, augmented by 24.6 MW from “sources elsewhere in the Visayas.”

“We reiterate that load restoration will be done conservatively, by matching loads to restored generation, to prevent repeated voltage failure. NGCP is ready to transmit power once it is available,” the grid operator said.

The Visayas grid needs about 300 MW to stabilize and is awaiting a PCPC facility, which has a 135-MW capacity, to synchronize back onto the grid.

In a statement, the Department of Energy (DoE) reminded the NGCP to “adhere to its responsibilities as system operator in ensuring supply security and reliability of the grid.”

“NGCP is in a position to anticipate system disturbance such as what happened yesterday, which unfortunately resulted in the isolation of Panay from the rest of the Visayas grid due to the simultaneous tripping of power plants that caused multiple power interruption affecting other power plants and distribution utilities (DUs),” Energy Undersecretary Rowena Cristina L. Guevara said.

Meanwhile, the Energy Regulatory Commission (ERC) said it requested additional data from the NGCP and the generation companies to assist in its review of the incidents.

“The ERC understands the inconvenience this situation has caused to the consumers of Panay, and we assure the public that every effort is being made to restore power as quickly as possible,” ERC Chairman Monalisa C. Dimalanta said.

Overall, the plant outage has affected a distribution utility and seven electric cooperatives, according to the NGCP.

These are MORE Electric and Power Corp., Guimaras Electric Cooperative, Inc., Iloilo Electric Cooperative, Inc. (ILECO I), ILECO II, ILECO III, Capiz Electric Cooperative, Inc., Antique Electric Cooperative, Inc., Aklan Electric Cooperative, Inc., and Guimaras Electric Cooperative, Inc. — Sheldeen Joy Talavera