Philippines grid hits red alerts

The Department of Energy on Thursday ordered the National Grid Corporation of the Philippines and power generators to restore grid stability after red and yellow alerts hit Luzon and Visayas for a second straight day. The alerts were triggered by forced outages and derated capacity at multiple plants, tightening reserves and prompting rotating brownouts in parts of the country. Meralco said about 200,000 customers were affected by emergency manual load dropping on May 13, and it published new rotating outage schedules for May 14. NGCP said the Luzon yellow alert that followed Wednesday’s red alert was lifted at 2:03 a.m. on Thursday after available capacity improved. ### How did the alerts spread across the two main grids? NGCP said on May 14 that Luzon and Visayas would again be placed under red and yellow alerts in the afternoon because several plants remained on forced outage or were operating below capacity. The grid operator said Luzon was scheduled for red alert from 4 p.m. to 7 p.m. and yellow alert from 3 p.m. to 4 p.m. and 7 p.m. to 10 p.m., while Visayas was set for red alert from 6 p.m. to 7 p.m. and yellow alert from 1 p.m. to 6 p.m. and 7 p.m. to 9 p.m. (gmanetwork.com) On May 13, NGCP had placed the Luzon grid under red alert from 3 p.m. to 8 p.m. and yellow alert from 2 p.m. to 3 p.m. and 8 p.m. to 10 p.m., according to GMA News and ABS-CBN reports citing the company. Visayas was also placed under yellow alert that day. ### What pushed reserves so low? NGCP said forced outages and derated capacity removed thousands of megawatts from the system. (gmanetwork.com) GMA News reported on May 14 that more than 5,500 MW of capacity was unavailable across the affected grids, while an earlier April yellow alert had already underscored how plant trips and reduced output could quickly remove more than 5,000 MW from Luzon supply. (gmanetwork.com) ABS-CBN reported that on May 13 alone, 4,681.6 MW was unavailable to the Luzon grid, leaving available capacity at 12,447 MW against peak demand of 12,537 MW during the red alert period. NGCP defines a red alert as a condition in which supply is insufficient to meet consumer demand and transmission reserve requirements, while a yellow alert means reserves have fallen below required levels but supply remains enough to meet demand. (gmanetwork.com) ### How extensive were the outages for customers? Meralco said emergency manual load dropping began at 3:23 p.m. on May 13 after NGCP declared red alert on the Luzon grid. GMA News reported the interruptions lasted an average of three hours and affected roughly 200,000 Meralco customers. (abs-cbn.com) On May 14, Meralco published six tentative manual load dropping events between 4 p.m. and 10 p.m. in parts of its franchise area. GMA News said the distributor expected rotating brownouts of about two hours each, while its advisory listed affected circuit groups by schedule. ### What did the Energy Department order? The Department of Energy said on May 14 that generation companies must resolve plant issues immediately and return unavailable capacity to the grid. (gmanetwork.com) GMA News reported the agency also directed NGCP to ensure transmission facilities were available and reliable, and to carry out restoration and contingency measures to stabilize the system. (gmanetwork.com) The DOE order followed renewed concern over whether generation and transmission operators were prepared for peak demand and plant outages. That scrutiny has centered on restoration timing, contingency plans and the ability to bring units back online quickly enough to rebuild operating reserves, according to the department’s statement as reported by local media. (gmanetwork.com) ### What changed overnight before Thursday’s fresh alerts? NGCP said the Luzon yellow alert was lifted at 2:03 a.m. on May 14 after available capacity rose to 11,982 MW and peak demand eased to 11,194 MW. That improvement ended the overnight alert, but it did not prevent new red and yellow alert periods from being scheduled later on Thursday. (gmanetwork.com) Meralco’s May 14 advisory and DOE’s order set the next checkpoints for consumers and regulators. The utility’s posted manual load dropping windows covered 4 p.m. to 10 p.m., while the department said NGCP and generators were expected to carry out restoration and contingency actions as the afternoon and evening peak approached. (company.meralco.com.ph) (gmanetwork.com)