Mindanao blackout traced to broken switch in Agus 7
The initial results of an investigation have traced the seven-hour power outage in Mindanao on Sunday to a broken connection asset of the National Power Corp. (Napocor) in the Agus 6/7 hydroelectric power plant complex in Iligan City, Lanao del Norte province.
In a briefing Monday at the Department of Energy (DOE), National Transmission Corp. president Rolando Bacani said a power conductor from the Agus 7 switchyard fell on the capacitor voltage transformer (a metering equipment) of the National Grid Corp. of the Philippines (NGCP). He said the final results of the inquiry could be released on April 15.
NGCP head for Mindanao systems operations Eugene H. Bicar said their line safety system kicked in with a slight delay while Napocor’s corresponding safety system did not activate. The resulting power disturbance flowed along the transmission line in the northern part of the grid.
Since 700 megawatts out of Mindanao grid’s 900-MW supply capacity comes from the northern part where Agus is located, there was under-frequency in the southern areas, which brought the whole system down, said Cynthia Alabanza, NGCP spokesperson.
She said initial investigations showed it was a technical matter and not likely security-related.
Napocor owns the power conductor, which is part of a “connection asset” or a point-to-point transmission facility that connects the Agus 6/7 switchyard to the transmission superhighways of NGCP. However, NGCP, a private firm, maintains the connection asset under an agreement with Napocor since the state firm no longer has linemen following the deregulation of the energy sector.
Energy Secretary Carlos Jericho Petilla said the investigation was ongoing and the main purpose was to find out what happened and determine how to prevent further disturbances in the Mindanao grid.
Napocor owns the connection asset but the NGCP maintains it under an agreement since the state-owned firm no longer has linemen after the energy sector was deregulated.
No sabotage
Petilla said initial investigations did not point to a sabotage.
“We are not ruling out any possibility but the initial report is that there was no explosion, there were no electric towers damaged. Usually, if it is terrorism-related, those infrastructures are targeted,” he told reporters Monday at Camp Crame during the signing of an agreement for the installation of solar-generation systems at the Philippine National Police headquarters.
Meanwhile, the privately run 210-MW Mindanao coal-fired power plant is operating, Steag State Power Inc. (SPI) spokesperson Jerome Soldevilla said via text message. The power plant is the largest connected to the Mindanao grid.
The system-wide power outage in Mindanao took place on Easter Sunday, at 1:01 a.m. Transmission services were restored at 7:50 a.m., NGCP said.
Distribution utilities and electricity cooperatives were individually able to restore household-level services within the day, according to the DOE.
Back to normal
The last Mindanao-wide power outage was on Feb. 27, 2014. Energy officials said the interruption was caused by the tripping of several power plants in Mindanao, starting with the state-owned Agus 1 power station switchyard in Marawi City, Lanao del Sur province.
It was later found that the 210-MW Mindanao coal-fired power plant had an “unwanted loss” of generation output (from 210 MW to 160 MW) just as there was a surge in electricity demand. The antiquated Agus 1 hydroelectric power plant was unable to handle the combination of events and had tripped, according to the probe.
The Agus 1/2 power station complex is located in Marawi City, Lanao del Sur. The rest, up to Agus 7, are located in Lanao del Norte.
In Davao City, the Mindanao Development Authority (Minda) said power all over the grid was restored by 8 a.m. on Sunday after NGCP mobilized teams to troubleshoot the problem.
Systems of the power plants in Mindanao had started to synchronize, putting the grid back to normal operations but in reduced capacity because of the low water levels.
“Most of the large power plants synchronized, starting 10 a.m. on Sunday. The situation is generally back to normal as the system regains stability,” said Romeo Montenegro, director for investment promotions and public affairs of Minda.
Coincidence?
Bayan Muna Representative Carlos Zarate on Monday accused the Aboitiz group of staging the massive blackout to justify the entry of more coal plants.
Zarate pointed out that the unexplained power loss occurred just when the Aboitiz-owned Therma South opened its 300-MW coal-fired plant in Davao.
“Was this just a coincidence? This island-wide blackout is now becoming an annual occurrence as it also happened on Feb. 27, 2014, when the Aboitiz-controlled Steag State Power Inc. coal-fired power plant in Villanueva, Misamis Oriental, mysteriously dropped its capacity from 200 MW to 160 MW,” Zarate said.
Zarate said the DOE’s failure to explain the blackout could be part of its game plan “to make it appear that the supply is lacking and justify the entry of more coal plants.”
Blackmail
He said the timing of the blackout was suspicious considering that the Aquino government was pushing for the privatization of Agus-Pulangi Hydro Power Complex, which provides at least 50 percent of Mindanao’s power requirements.
In January last year, Bayan Muna accused private power generators led by Philippine Independent Power Producers Association president Luis Miguel Aboitiz of blackmailing electricity consumers into accepting higher power rates supposedly to prevent blackouts.
Bayan Muna has criticized the government privatization of the power sector under the the Electric Power Industry Reform Act, which has left the captive public at the mercy of profit-hungry corporations.
It has opposed the privatization of the remaining hydroelectric power plants and power barges in Mindanao and has pushed for the transfer of their maintenance, rehabilitation and upgrading to the Napocor.
In May last year, Bayan Muna sought the probe of the government sale of two power barges in 2010 to Therma, which profited from last year’s power supply shortage in Mindanao. With reports from Julie M. Aurelio and Gil C. Cabacungan in Manila, and Karlos Manlupig, Inquirer Mindanao
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