Outages hit parts of the Luzon grid on Friday afternoon as peak demand outpaced supply, triggering the Interruptible Load Program (ILP) wherein volunteer businesses use their own generator sets to ease the strain on the grid.
The Department of Energy (DOE), through OIC-Undersecretary Mylene Capongcol, said the Luzon grid went from yellow alert (referring to thin power supply reserves) at 10 a.m. to red alert (referring to power supply deficiency) at 1 p.m.
This triggered the ILP that is spearheaded and coordinated by the country’s largest distribution utility, the privately owned Manila Electric Co. (Meralco).
The power situation in the grid is expected to ease over the weekend since power demand is usually weak, Capongcol said.
Meralco officials confirmed that ILP participants were asked to deload (use their own generator sets and temporarily stop drawing power from the grid) from 1 p.m. to 3 p.m. to help reduce peak demand. “We survived (outages) for now,” said company spokesperson Joe Zaldarriaga.
In Meralco’s franchise area alone, the power deficiency was as follows: 30 megawatts (MW) at 1 p.m., 200 MW to 220 MW at 2 p.m., and 160 MW at 3 p.m.
The franchise area, along with the rest of the Luzon grid, was seen to be back to yellow alert after 4 p.m.
The total capacity enrolled in the ILP program is 826 MW. That is the amount of power demand that participating businesses can ease from the grid during the peak demand hours of 10 a.m. to 3 p.m. to avoid deficits that cause outages.
Presently, power plants on scheduled maintenance shutdown are Malaya thermal unit 1 (300 MW), Botocan hydro 2 (10 MW), Pagbilao coal power unit 1 (382 MW) until April 30, and Magat hydro units 3 and 4 (95 MW each) until April 16.
These were scheduled as part of efforts to have all power plants running on the week of the May 9 national elections, when power supply is even more crucial to ensure smooth voting, counting and transmission of results from the provinces to Manila.
However, some power plants are suffering from limited capacity and a number broke down outside of schedule. Calaca coal power unit 1 capacity was limited to 190 MW (from 200 MW) and Calaca 2 was limited to 220 MW (from 300 MW). Malaya also had lower capacity at 130 MW, down from 330 MW.
So-called forced outages (unexpected power plant shutdown) took place at Kalayaan hydro units 3 and 4 (180 MW each), with each unit expected to be back Friday night.
Quezon Power (Philippines) Limited’s coal power plant (289 MW) tripped at 6:24 a.m. but was put back online at 5:30 p.m. San Roque hydro 3 (145 MW) and Ambuklao hydro (105 MW) were also out, with no advice on the estimated time of restoration at press time.
It is not yet clear why the power plants shut down out of schedule. In the past, among the usual reasons are boiler tube leaks and power generation engine problems.
Energy Secretary Zenaida Y. Monsada said all consumers can help prevent outages during peak hours by saving electricity and/or shifting their activities to nonpeak hours such as early morning or at night.