power and water

Rotational blackouts seen as NGCP raises red alert for Luzon grid

Aika Rey
(4th UPDATE) The red alert is eventually lifted at 4:07 pm on Monday, May 31. But yellow alert is set for 7 pm to 10 pm.

Plant outages amid high temperatures prompted the National Grid Corporation of the Philippines (NGCP) to place the Luzon grid under red alert on Monday, May 31 – the first time it has done so since June 2019.

A red alert, which means there is insufficient power supply in the grid, was in effect starting 1 pm on Monday.

It was eventually lifted at 4:07 pm, when peak demand was expected to reach 10,439 megawatts while available capacity was at 11,419 MW, leaving 980 MW of reserves.

But in its advisory, the NGCP said a yellow alert will be raised from 7 pm to 10 pm on Monday. A yellow alert is raised when reserves fall below the capacity of the biggest plant in the Luzon grid, which is at 647 MW.

The NGCP also raised a yellow alert for 11 am to 1 pm on Monday. A yellow alert does not necessarily mean power outages.

Rotational blackouts

When red alert was in effect on Monday afternoon, this was the initial list of areas told to expect rotational blackouts:

  • Parts of Isabela
  • Entire province of Quirino
  • Olongapo City
  • Parts of Quezon
  • Parts of Camarines Sur
  • Parts of Meralco-serviced areas

The NGCP later said the following areas would also be hit by rotational blackouts from 2 pm to 3 pm:

  • Ilocos Norte
  • La Union
  • Zambales 
  • Quezon
  • Camarines Norte
  • Albay
  • Metro Manila

Energy Undersecretary Felix Fuentebella had said the blackouts would last under one hour.

Red alert was raised after the NGCP projected that demand would peak at 11,514 megawatts while supply was at 11,729 MW, leaving only a 215-MW reserve.

According to officials, there should be reserves of at least 400 MW to prevent rotational blackouts.

Plant outages

On Monday, planned outages led to 435 MW in lost capacity. For 2021 so far, total outages, including unplanned plant shutdowns, have reached 1,285 MW.

Energy Assistant Secretary Redentor Delola said there is a possibility that yellow and red alerts would “last for the next couple of days” because of the lost capacity.

“We are able to maintain a reserve level of 1,000 MW to 1,200 MW. Now that we no longer have Ilijan (natural gas plant), we are left with 400 to 600 MW. But with the additional planned outage of San Roque (hydroelectric plant), that brought us to the red alert level,” Delola said.

Fuentebella reiterated the department’s stance that sufficient reserves are needed and warned that penalties could be imposed on generation companies.

“We were highlighting this need since two years ago. Sadly, we don’t want to impose any penalties, but we really have to make those accountable responsible for the situation,” Fuentebella said.

The DOE said the GNPower Mariveles and Sem-Calaca coal plants have been offline since February 2021 and December 2020, respectively.

Earlier, the DOE said it was not expecting power outages for the dry season as long as there would be no additional plant shutdowns.

The DOE also said on Monday that demand is dependent on the heat index as well, since a 1°C increase in temperature could lead to a 100-MW increase in power demand.

The last time the Luzon grid was placed under red alert was for certain hours from June 18 to 21 in 2019. – Rappler.com

Aika Rey

Aika Rey is a business reporter for Rappler. She covered the Senate of the Philippines before fully diving into numbers and companies. Got tips? Find her on Twitter at @reyaika or shoot her an email at aika.rey@rappler.com.