The Department of Energy (DOE) has ordered an investigation into a series of yellow and red alerts affecting the Visayas Grid, as authorities move to address the thinning power supply in the region.

In a statement, the DOE said its Electric Power Industry Management Bureau is now examining the causes of repeated grid alerts, which indicate insufficient electricity reserves and potential outages.

Energy Secretary Sharon Garin has directed the National Grid Corporation of the Philippines, power generation companies, and other relevant operators to expedite the restoration of affected transmission lines and generating units. The directive aims to stabilize the Visayas Grid following fresh declarations of red and yellow alerts.

Initial reports showed that the Iloilo–Panay Energy Development Corp. (PEDC) 138-kilovolt Line 3 tripped on Wednesday, July 8, resulting in the isolation and forced outage of PEDC facilities.

The DOE also reported a failure of the Lapu-Lapu–Basak 69-kilovolt transmission line. Meanwhile, an ongoing investigation is looking into a reported outage involving Palm Concepcion Power Corporation in Panay.

The energy department assured the public that heightened monitoring is in place and that necessary measures are being implemented to protect the power system and mitigate the continued decline in electricity supply across the Visayas.

The Visayas Grid was again placed under red and yellow alert status on Thursday, July 9, due to continued thinning of power supply.