Manila (AFP) - Power was restored in the southern Philippines Friday after a massive blackout left millions without electricity for hours, but officials warned of more outages due to ageing equipment.
All of the Mindanao region, home to about 25 million people, regained power around 12.00pm (0400 GMT), 32 hours after lights went out before dawn Thursday, Energy Secretary Jericho Petilla said.
The suspected cause of the region wide blackout was equipment failure at a high-voltage switchyard that utility officials said is about 26 years old.
"Some of these are really old equipment, probably older than you," Petilla told reporters at a Manila news conference.
The breakdown triggered the automatic shutdown of a nearby government-owned hydro power plant that draws its power from a dam, and unleashed a cascading effect on other power plants across the region, utility officials said.
It was the first time in 12 years that the region had suffered a total outage, though partial outages had occurred in between, Petilla said.
The authorities are now investigating the breakdown, which meant the power plant nearest the original failure had to be temporarily shut down, he added.
That closure is expected to further degrade the thin generating capacity reserves of the region, which has been grappling with chronic power shortages for years.
Petilla warned of daily rolling outages of up to three hours in the coming months where there is less rainfall to be collected at Mindanao's government-owned hydro-electric dams.
An electricity shortage last year forced the country's power transmission firm, National Grid Corp. of the Philippines, to ration supply in Mindanao.
This led to daily outages lasting up to 12 hours, which damaged the local economy.