Mindanao is currently experiencing rotating power outages after several power plants in the area have been shut down, with the situation expected to normalize in the next two weeks.

In a statement on Friday, the National Power Corp. (Napocor) said four of its generation facilities and two independent power producers in the South "have been temporarily shut down for a variety of reasons."

"Hopefully, we will already have a normal power supply situation by Sept. 26," Napocor said.

"The shutdown resulted in a deficient capacity to meet the Mindanao grid’s electricity demand. Rotating brownouts have to be implemented during peak hours," it said. "Power supply is normal during peak hours."

The shutdowns have taken off more than 400 megawatts (MW) out of a total 620-MW dependable capacity from the grid.

Napocor said the lower power supply was due to the tripping of Agus 1 (unit 2) and the shutdown of the 100-MW Western Mindanao Power Corp., both of which coincided with the scheduled preventive maintenance of Agus 2 (unit 1), Agus 5 (unit 1) and Mindanao (STEAG) coal (unit 1).

Napocor said they are "coordinating with the proper agencies such as the National Grid Corporation (NGCP) of the Philippines, and our customers involved in power distribution for updates on the power supply situation."

In a press conference also on Friday, Energy Secretary Angelo T. Reyes said Napocor and the NGCP were asked to submit reports on the Mindanao power situation. "We are checking reports on the power situation in Mindanao," he added.

Department of Energy data indicate that the total dependable capacity in the Mindanao grid last year stood at 1,510 MW. The power supply situation in Mindanao is estimated to reach critical levels this year, with the grid expected to have a peak demand of 1,525 MW on top of a 100-MW foreseen additional capacity need, or a total of 1,625-MW requirement.

Meanwhile, power supply in Mindanao’s major cities was generally stable as of late Friday afternoon. Minor power problems were experienced in the Zamboanga Peninsula and Sarangani province in South-Central Mindanao.

Major cities such as Davao in Southern Mindanao and Cagayan de Oro and Iligan in Northern Mindanao hardly experienced power interruptions during the day.

The Davao Region and Northern Mindanao combined account for at least three-fourths of the island’s power demand, which is roughly estimated at one gigawatt.