By Alena Mae S. Flores – September 28, 2017 at 07:01 pm
Grid operator National Grid Corp. of the Philippines declared a ‘yellow alert’ in the Luzon grid for a few hours Thursday amid thin reserves brought about by the outage of six power plants.
Yellow alert means that power reserves fall below the capacity of the largest synchronized unit of the grid which in Luzon is the 647-megawatt Sual power plant. This situation could result in blackouts if the system would not be very quick to respond.
Energy Undersecretary Felix William Fuentebella told reporters several power plants went on planned and unplanned outages Thursday, while some plants were derated, or their generating capacities were reduced.
Fuentebella said ‘yellow alert’ covered two hours. “It’s basically thinning of reserves by about 150 MW from expected 624 MW required,” he said.
Fuentebella said the Energy Department coordinated with retailer Manila Electric Co. to put in place the interruptible load program, where select participants could deload from the grid and run their own generating sets.
“We also have in place the ILP under Meralco, also covering 150 MW. The deficit is only on the reserves, not on the supply. A yellow alert is not a deficit in supply. It is only a signal that reserves are getting to be smaller. The red alert is the one that should be alarming,” he said.
Among the plants that went on unplanned outages were Ilijan B (600 MW), Limay 7 (60 MW), Makban 5 (55 MW) and Sual 2 (647 MW). Plants that were on planned outages were Kalayaan 3 and 4 (360 MW) and Lorenzo 1 (265 MW).
NGCP raised the yellow alert from 11 a.m. to 12 p.m. and 2 p.m. to 3 p.m. as available capacity for Luzon reached 10,473 MW while demand hit 9,676 MW.
NGCP lifted the yellow alert status at 2:30 p.m. but Meralco president Oscar Reyes said yellow alerts were now a “reality” and showed the “vulnerability” of the Luzon grid.
“The reason for yellow alerts are outages. But if you’ve got the confluence of outages three years ago, it poses a risk to continued commercial industrial activity,” Reyes said.
Reyes said the series of yellow alerts in the Luzon grid since late August underscored the need for additional power capacities to meet the increasing demand.
“I think, it just shows potential vulnerability of the entire system and you’re better with adequate capacity. If we cut it too thinly, and there are a bit delays, then we’re going into a situation as we move to 2019 to 2022,” he said.
Reyes said Meralco would not want to raise the alarm of power shortage, but “it’s really just a realization that you’re better off with adequate capacity because it takes time to build.”
Power plants take at least three years to build. Meralco has pending applications for more than 3,500 megawatts of capacity for supply contracts with seven power generators.