Energy chief orders probe after Luzon grid tripping triggers widespread outages

National

WIDESPREAD power interruptions hit Luzon after key high-voltage transmission lines tripped, disrupting thousands of megawatts of supply and prompting the Department of Energy (DOE) to launch an investigation.

Energy Secretary Sharon Garin ordered a full probe into the May 13 tripping of the Tayabas–Ilijan and Ilijan–Dasmariñas 500-kilovolt transmission lines operated by the National Grid Corporation of the Philippines (NGCP). The lines carry about 12 percent of Luzon’s electricity supply.

“An incident of this scale demands full technical disclosure, clear accountability and immediate corrective action,” Garin said in an Inquirer report.

According to the DOE, the disturbance led to the disconnection of 2,462.1 megawatts of natural gas capacity, triggering outages across multiple areas. Ilijan Blocks A and B and several units of Excellent Energy Resources Inc. were automatically taken offline, while power transfers from Luzon to the Visayas were also disrupted amid already tight supply conditions.

The Grid Reliability Task Force (GRTF), composed of the DOE, Energy Regulatory Commission, Independent Electricity Market Operator of the Philippines, TransCo, and PSALM, will conduct a technical review to determine the root cause. The DOE has also requested NGCP to submit operational data and incident reports.

The probe comes as both the Luzon and Visayas grids remain under alert due to tight supply. NGCP placed Luzon on red alert from 2 p.m. to 11 p.m., with yellow alerts before and after that period.

Available capacity stood at 12,075 megawatts versus peak demand of 12,927 megawatts. The situation worsened after GNPower Dinginin Unit 1 tripped, removing another 668 megawatts from the grid.

NGCP also reported that 17 power plants have been on forced outage since the start of the month, while 14 others are operating at reduced capacity, bringing total unavailable capacity to 4,828 megawatts.

Manila Electric Co. (Meralco) said it secured about 250 megawatts of deloading commitments under its Interruptible Load Program to help stabilize supply, but warned that manual load dropping or rotating outages may still occur if conditions worsen. Around 900,000 customers were affected during Thursday’s red alert before service was restored.

NGCP added that the affected 500-kV lines were restored earlier in the week, though some generating units have yet to fully resynchronize with the grid.(MyTVCebu)