MANILA (UPDATE) - The House Committee on Energy on Thursday sought for an "efficient" timeline for plants to restore operations during outages after the forced shutdown of some facilities caused the Luzon power grid to go on yellow and red alert early this week.
"How long is the efficient amount of time for them to get back online? Because these are the things we should look at. DOE should look at how long certain power plants should be back online," Energy Committee Chair Lord Allan Velasco said at a hearing.
"We have to find out how come they did not go back online after 20-25 hours, so that we could actually try to not go into those yellow and red alerts," Velasco said.
The Luzon grid went into red and yellow alert on Monday following the forced outage of seven power plants.
"Can you just imagine if a certain power plant can go back in 10 hours but it gets online after 20 hours? Then that should ring bells, sound the alarms. How come it took them 20 hours?" Velasco said.
The Department of Energy said it will provide data on the timelines of powering up and cooling down of different power plants.
"We don't have a complete and firm study on that. But we will provide the committee a study, because these are specific on the technology-basis. It depends on the ramping up and down capabilities," DOE Asec. Mario Marasigan said.
The DOE will also provide a matrix of data on the shutdowns, powering up, and synchronization of the power plants which were on forced outage starting Sunday.
During the committee's second hearing Thursday afternoon, Independent Electricity Market Operator of the Philippines (IEMOP) President and CEO Atty. Richard Nethercott presented the following timeline of the power plant outage:
- Two 2,850 kilowatt lines connecting Kadampat (Bolo) to San Manual (Nagsaag) tripped at 7:52 a.m. of Sept. 11
- System Integrity Protection Schemes (SIPS) was activated due to the incident, resulting in the disconnection of the Sual and Masinloc plants, with a total of 2,298 megawatts capacity
- At 8 a.m. of Sept. 12, a red and yellow alert was issued; total outage was measured at 6,164 megawatts
- Masinloc 1 went back online after synchronization at 12:39 a.m. of Sept 12; Sual 2 plant went back online at 12 noon later; and Masinloc 2 went online at 1:42 p.m.
- Masinloc 3 and Sual 1 went back online the following day (Sept. 13) at 6:44 a.m. and 9:10 a.m., respectively
"The following day (Sept 13), the supply and demand conditions went back to normal," Nethercott said.
The National Grid Corporation of the Philippines confirmed the sequence of events presented by the IEMOP, and assured that all power plants were informed of the outage when the tripping happened, as in the case in the Bolo-Nagsaag power plant.
The NGCP is still investigating what may have caused the trip in the Bolo-Nagsaag plant which caused the other transmission lines to trip and the other plants to be on forced outage.
Marasigan clarified that the shutdowns beginning Sunday which caused the yellow and red alert in the Luzon grid were emergency shutdowns and not a normal operating procedure.
"That's why some of these power plants needed to do a complete rechecking, kasi kung nagkaroon ng maliliit na diperensya sa kanilang emergency shut down, then they have to have corrective measures immediately," Marasigan said.
The official assured that in cases of extended outage due to maintenance, a resolution states designated and allowable time for a forced outage, providing for corresponding reprimand and penalties.
"Sa incident this week, hindi pa natin alam kung ano yung nag-trigger talaga sa situation. Kung ang nag-trigger ay yung power plant, syempre ang penalty sa power plant. Pero kung ang nag-trigger yung system at transmission, ang accountable doon ay ang system operator. On-going pa po ang investigation," Marasigan said.
(We dont know what triggered the situation. If its the power plants, then there's penalty. But if its system and transmission, then the system operator is accountable. The investigation is still on going.)
Philippine Independent Power Producers Association, Inc. (PIPPA) President Atty. Anne Estorco Montelibano agreed with Marasigan, differentiating "an emergency shut down, and a forced outage due to other reasons beyond our control like a transmission problem."
What happened underscored the need for sufficient ancillary services, Montelibano said.
"Kung meron tayong sufficient ancillary services, ibig sabihin kapag nag-fluctuate po ito, mape-prevent ang sinasabi nating automatic load drop, hindi magkaka-black out at hindi masisira ang planta," she said.
In her presentation during the committee hearing, Montelibano explained that the System Integrity Protection Scheme (SIPS) was triggered and tripped Sual 1 and 2 plants and the Masinloc 1, 2, and 3 plants after the Bolo-Nagsaag tripped.
The SIPS "are systems designed to detect abnormal power system conditions and initiate predetermined corrective actions to mitigate the impact of abnormal operating conditions," PIPPA explained.
"Instead of collapsing the entire grid 'pag nangyari ang surges, ang effect po ng SIPS, tini-trip po niya ang mga planta. Pino-protect niya ang mga planta. So ang nangyayari, automatic nagti-trip ang planta. 'Pag yun ang nagko-cause at nag-emergency shutdown ang planta, it depends on the technology, but we have to closely examine the damage incurred," Montelibano said.
"Magkakaroon ng distinction to be made if the outage is due to technical reasons or because nag-trip kami because of other reasons. We have to exercise our due diligence and prudence in inspecting plants to make sure the damage is not that great," she added.
"This is why we underscore the need for an efficient transmission network at walang congestion. One of the effects of SIPS is to trip the plants, which is very costly for us."