Was blackout a ‘supply matter’ or a case of mismanagement?

By Francis Allan Angelo, Jennifer P. Rendon, and Rjay Zuriaga Castor

Concerns ranging from spoiled leftover food from New Year’s celebration to work interruption and sweltering heat have dominated social media after hours long of power outages again hit Panay Island, Negros, and even Guimaras.

But who is really to blame for another round of blackouts that is now entering its second day? Insufficient supply or inefficient transmission or power grid facilities?

Power started to flicker at around 2:19 p.m. on Jan. 2. affecting the entire Western Visayas.

Shortly before 3 p.m., power outages blanketed the entire region.

At around 2:56 p.m., the National Grid Corporation of the Philippines (NGCP), a privately owned corporation in charge of operating, maintaining, and developing the country’s state-owned power grid, said in an advisory that there was a “multiple power plant tripping in Panay island. NGCP is working to restore voltage. Will post updates as they are available.”

It added that at 12:06 p.m. on Tuesday, “NGCP monitored the tripping of PEDC Unit 1 due to an internal issue. At 2:19PM, PEDC Unit 2, PCPC, and other plants tripped in Panay Island, isolating the same from the rest of the Visayas grid.”

It further stated, “the cause of the multiple tripping is unknown. 302 MW was lost to the grid, in addition to 150 MW on planned maintenance shutdown, including PEDC Unit 3. In total, 452 MW is unavailable. Currently, none of the power plants in Panay Island are generating power.”

PEDC or Panay Energy Development Corporation owns and operates 164 MW and 150 MW clean coal-fired plants in Iloilo City that utilize the Circulating Fluidized Bed (CFB) boiler technology.

Global Business Power Corp. has readily confirmed that PEDC Units 1 and 2 tripped Tuesday afternoon.

Its Unit 3, which can generate 150 megawatts (MW), has been under preventive maintenance works since Dec. 19, 2023.

At 3:24 p.m., the NGCP said that the Negros-Panay interconnection was restored after it tripped at 3:07 pm.

After two PEDC units tripped off, other power plants tripped including the Palm Concepcion Power Corp. in Iloilo province.

The blackout has also affected consumers of the Central Negros Electric Cooperative, Inc.

But at 3:24 p.m. Tuesday, NGCP reported that the Negros-Panay interconnection was restored after it tripped at 3:07 p.m.

The NGCP then issued a yellow alert citing the tripping of major plants at Panay that resulted in a low operating margin.

It said that the restoration of affected plants is ongoing.

“While NGCP did not implement manual load dropping, distribution utilities may implement load drops due to voltage sensitive loads or manual disconnection to secure voltage levels.”

It didn’t take long for Iloilo City Mayor Jerry Treñas to call on the NGCP to resolve the power disruption.

“I call on the Department of Energy and NGCP to resolve this problem at the earliest possible time,” he said.

Treñas said he is “utterly dismayed that due to an unstable supply, the whole Panay Island can be totally isolated.”

He also called on the NGCP to find a more sustainable solution to the problem.

He said the Regional Development Council (RDC) Infrastructure Development Committee will definitely look into it immediately.

Later that day, Treñas sent City Hall employees home. At around 10 p.m., he also announced the cancellation of classes.

Other local government units (LGUs) have also cancelled classes on Wednesday.

Meanwhile, MORE Power and Electric Co. (MORE Power), the sole electric distribution utility in Iloilo City, was able to energize 29.21 percent or 28.5 MW for its consumers by 7:18 in the evening.

Vital institutions such as hospitals are being prioritized for energization, it added.

But it wasn’t able to implement rotational manual load drop due to the unstable grid system.

Hence, after 24 hours since the grid disturbance, around 45 percent of MORE Power’s franchise areas still need to be energized.

NGCP said the grid needs about 300MW to stabilize. Large plants PEDC Units 1 and 2 (83MW each) and PCPC (135MW) need to be synchronized back to the grid for load restoration to occur.

WHO’S TO BLAME?

NGCP has pointed to unscheduled maintenance shutdowns of power plants.

“The unscheduled maintenance shutdowns of the largest power plants in Panay island was the primary cause of the power interruption. We emphasize the need for improved planning to ensure sufficient generation per island, with a well-balanced mix of fuels and technology,” NGCP said.

“Multiple plant trippings isolate Panay grid, NGCP renews call for a whole-of-industry approach to stabilize supply.”

The NGCP said it is renewing its call for a whole-of-industry approach, including better energy resource planning, following the January 2 power outage due to the tripping of multiple power plants which isolated Panay island from the rest of the Visayas grid.

It again noted its earlier statement that various power plants in Panay Island suffered multiple trippings on January 2, including PEDC Units 1 and 2 (83 MegaWatts each), and PCPC (135MW), among others.

“With the tripping of 3 of the largest power generating units and the planned maintenance shutdown of PEDC Unit 3 (150MW), 451MW or 68.75% of the total 656MW in-island generation was lost to the Panay sub-grid,” it noted.

The NGCP stated that maintenance shutdowns and deration of plants outside the Department of Energy’s (DOE) approved Grid Operating and Maintenance Program also contributed to the lack of power supply.

“We will be restoring loads conservatively, by matching loads to restored generation, to prevent repeated voltage failure. NGCP is ready to transmit power once it is available. The people must understand that we can only transmit power, we do not generate power,” stated the company.

The NGCP also underscored the need to conduct a more robust resource optimization planning by policy makers, to ensure that solutions to power system concerns are approached from all angles, and the most efficient ones are prioritized.

Given the configuration of the Panay sub-grid and its dependency on variable energy sources in Negros when it loses internally generated power, NGCP also noted the need to provide sufficient non-variable sources to stabilize the system. The company also included its Cebu-Negros-Panay Stage 3 project (CNP3) as a contributing solution.

But in an emergency meeting called by the Regional Development Council at the National Economic Development Authority, NGCP was unable to explain why the grid collapsed when PEDC Unit 1 momentarily tripped when it was supposed to install protection systems that would prevent such incidents.

Sources privy to the meeting told Daily Guardian that NGCP was still investigating why its facilities buckled.

Another question that NGCP officials failed to answer was about their supply backup or ancillary services that will ensure a steady stream of electricity to prevent massive and prolonged blackouts.

“If only NGCP had ample and reliable backup, they could have reenergized the grid within 2 hours and we don’t have to suffer 24-hour blackouts,” one source told Daily Guardian.

PCPC IS KEY

The prolonged agony caused by the ongoing power outage may be relieved as soon as the Panay grid synchronizes with the Palm Concepcion Power Corporation (PCPC) in Concepcion, Iloilo.

The PCPC can generate a load of 135 megawatts (MW).

The PCPC is expected to round up its generation system on the evening of January 4, said Engr. Bernard Bailey Del Castillo, Vice President for Network Development and Operations Group of MORE Electric and Power Corporation (MORE Power).

“The latest update we hear from PCPC is they will start to come in or start to round up tomorrow evening,” he said.

Del Castillo said this means that Iloilo City consumers may experience a rotating brownout or interruption until tomorrow evening.

“The only thing nga mabalik sa normal etong grid condition subong is mabalik si PCPC power plant, siya talaga ang savior natin right now,” he added.

Meanwhile, PEDC announced that its units 1 and 2 have already synchronized to the Panay grid at 7:45 am on January 3 and at 11:45 pm on January 2, respectively.

The two PEDC units are currently contributing a combined capacity of 139.6 MW to the Panay grid.