Power firm implements daily rotational brownouts

THE Zamboanga City Electric Cooperative (Zamcelco) is implementing one to two-hour rotational brownout daily, as result of the load curtailment implemented by the National Grid Corporation of the Philippines (NGCP).

The rotational brownout has been implemented since Monday until April 24, said Zamcelco General Manager Reinerio Ramos.

Ramos said the load curtailment was implemented due to the scheduled total plant shutdown of Pulangi 4 Hydro Electric Plant for its annual preventive maintenance.

Ramos, however, said the duration of the rotational brownout would depend on the daily power allocation to Zamcelco, the reason why the brownout would last to a minimum of one hour to a maximum of two hours for each of Zamcelco's feeder lines.

Zamcelco, which has a maximum power demand of 86.02 megawatts daily, has 24 feeder lines, serving this city's power consumers.

On Tuesday, Zamcelco implemented a two-hour rotational brownout in each of the 24 feeder lines due to the reduction of 41.2 megawatts to the power cooperative's allocation.

However, the NGCP emphasized it does not own, operate or shut down power-generating plants but as system operator, it has information on the available capacity, system peak and reserves in the power system.

The NGCP said approximately 100 megawatts of power was taken out of the Mindanao grid due to the unexpected unavailability of Units 2 and 4 of Agus 6, Units 1 and 2 of Agus 7, Unit 1 of Agus 1.

The NGCP added that six power plants are operational “but derated by the owners and operators.”

These are: Agus 1, 30 megawatts; Agus 2, 90 megawatts; Agus 5, 50 megawatts; Agus 6, 100 megawatts; Western Mindanao Power Corporation, 90 megawatts; and, Southern Power Philippines Corporation, 40 megawatts.
“In instances when there is a deficiency in the power supplied by the different power plants, NGCP implements load shedding based on an allocation matrix load prepared by the generators or power plants themselves,” the NGCP said.

“In Mindanao, this load shedding matrix is from the National Power Corporation,” the NGCP added.

It said that the load shedding is then implemented across the Mindanao grid through the area control centers of NGCP in Cagayan de Oro, General Santos, Davao, Butuan, Zamboanga and Iligan.

The power interruptions actually experienced by the end-consumers in the household levels will depend on the implementation scheme of the particular distribution utility in the area, the NGCP said. (Bong Garcia)