By Sheldeen Joy Talavera, Reporter
POWER SUPPLY STRAINS in the Visayas worsened after a major earthquake triggered widespread outages in Mindanao, leading to a supply shortfall that prompted grid alerts across both island groups on Wednesday.
In an advisory, the National Grid Corp. of the Philippines (NGCP) placed the Visayas grid under red alert from 1 p.m. to 7 p.m. and yellow alert from 7 p.m. to 9 p.m.
During the period, available capacity stood at 2,556 megawatts (MW), while peak demand hit 2,423 MW.
NGCP said the decline in the power supply imported by the Visayas grid from Mindanao grid was one of the factors that contributed to the declaration of a red alert.
The Visayas is a net importer of power from Luzon and Mindanao, making it vulnerable to power supply constraints when the interconnection from the two island grids is limited.
A red alert, the highest alert level, is issued when power supply is insufficient to meet consumer demand. A yellow alert is declared when power buffer is not enough to meet the transmission grid’s contingency requirement.
NGCP declared a yellow alert over the Mindanao grid from 12 p.m. to 3 p.m. due to unavailability of several power plants and high forecast demand. The grid alert was lifted at 3:50 p.m.
A magnitude 7.8 earthquake struck off the coast of Sarangani province on Monday, causing outages of some power plants that led to power interruptions affecting around 850,000 households in Mindanao.
Mindanao was operating at 2,731-MW capacity against a peak demand of 2,611 MW, NGCP said.
Mindanao was placed under yellow alert for the first time this year, while the Visayas has recorded 29 yellow alerts so far.
Energy Secretary Sharon S. Garin on Wednesday said restoration efforts are still ongoing, with affected power plants targeted to gradually return online.
“We’re trying to be as fast as we can, but we have to be very careful because if you bring it (power plant) too fast, the blackout could last even longer in the long term. So, we’re asking for patience. Within the week, Mindanao should return to normal,” she told reporters on the sidelines of an event organized by the Management Association of the Philippines.
Alexander D. Ablaza, president of the Philippine Energy Efficiency Alliance, said the increase in demand was due to the overlapping demand of commercial, industrial and residential customers.
“Creating sufficient power reserves for the Visayas grid will need a supply-side solution of enabling adequate submarine cable transmission capacities between islands especially to import more power from Leyte and the Mindanao grid,” Mr. Ablaza told BusinessWorld.
He said that local government units, distribution utilities and electric cooperatives should implement more aggressive demand-side measures. These include load-shifting interventions and energy efficiency programs that could shave off more than 2,000 megawatts of peak demand, which continues to rise due to high heat indices and increased economic activities.
Meanwhile, Ms. Garin said the department will issue within the first half its assessment on power plants in the Visayas that are still on forced shutdown before deciding on the potential penalty that might lead to their closure.
“We need to be prepared before imposing any penalties. If there might be closures, if, for example, we cancel a license, we have to make sure that we have replacement power,” she said.
Ms. Garin said that President Ferdinand R. Marcos, Jr. directed agencies to find immediate and long-term solutions to power supply issues.
“The power supply outlook for Luzon and Mindanao is okay. Visayas is problematic. Today and next year, if we do not do anything, Visayas will still have these red and yellow alerts,” she said.
Sharon Ocampo-Montañer, director of the market operations service at the Energy Regulatory Commission (ERC), said the agency and the Department of Energy are closely monitoring the plants in the Visayas through joint inspections of the affected facilities.
“We’re continuously working to help those plants get restored and we’re closely monitoring their recovery so they can return to operation as soon as possible,” she told reporters.
Ms. Ocampo-Montañer said “definitely there are several plants that are exceeding the outage allowance.”
The ERC is implementing a reliability index, which sets the maximum days of planned and unplanned outages per year, varying by generating plant technology.
She said penalties that may be imposed on concerned plants would depend on the impact of the lost capacity on the grid.


