QUEZON CITY, June 22, 2022 – Manila-based climate and energy policy group Institute for Climate and Sustainable Cities (ICSC) reiterated the urgent need for flexible and distributed power generation in the Philippine power system as the National Grid Corporation of the Philippines (NGCP) raised a red alert status over the Luzon grid on Saturday, affecting over one million households in Metro Manila and nearby provinces.

“While the June 18 transmission line tripping pushed the power system into the red alert level, the power system was already showing abnormal operation even weeks before, as indicated by the skyrocketing Wholesale Electricity Spot Market (WESM) generation costs,” said ICSC chief data scientist Jephraim Manansala who co-authored the “Luzon Power Outlook: Determining the Adequacy of Power Supply for April to June 2022” report released earlier this year.

The Luzon Power Outlook report predicted a shortfall in the country’s power supply in the second quarter of 2022, leading to a red alert status and possible blackouts over the Luzon grid.

According to the Department of Energy (DOE), the deficiency in Luzon’s power supply on Saturday was caused by the tripping of Hermosa-Limay 230 kiloVolt (kV) transmission lines 1 and 2, which disconnected two power plants in Bataan from the Luzon grid. The NGCP said the lines were restored at around 3:00PM the same day.

Meralco, the largest distribution utility in Luzon, said automatic load dropping (ALD) occurred on Saturday due to the decrease of approximately 1,200 megawatts (MW) in their load, as a result of the transmission lines tripping. According to Meralco spokesperson Joe Zaldarriaga, the ALD affected around 1.6 million of their customers from portions of Caloocan, Valenzuela, Malabon, Manila, Makati, Muntinlupa, Las Piñas, in Metro Manila, as well as parts of Bulacan, Rizal, Laguna and Cavite.

The red alert was lifted late in the afternoon, but the NGCP noted that the Luzon grid was still on yellow alert up until 11:00PM on the same day.

Analyzing the spot market data over the weekend, Manansala cited the main causes of the red alert status in the Luzon grid:

  1. The Luzon power system had sufficient but expensive supply these past few weeks due to the recurring downtime of a number of baseload power plants at overlapping periods, such as Aboitiz Power Corporation’s GNPower Dinginin (GNPD) and GNPower Mariveles Energy Center (GMEC); Semirara Mining and Power Corporation’s Calaca; Pangasinan Electric Corporation’s Sual, Southwest Luzon Power Generation Corporation, and National Power Corporation’s (NPC) Ilijan plant. These downtimes were not scheduled, as confirmed by the DOE Grid Operating and Maintenance Program (GOMP), which shows that no planned outages should happen from April to June 2022.

The unplanned outages resulted in the use of multiple diesel power plants which are significantly more expensive as influenced by the ongoing Ukraine invasion. The high diesel plant utilization led to high WESM power costs, reaching an average of more than PHP10.00 per kilowatt-hour (kWh) daily and a peak price of more than PHP30.00 per kWh.

  1. The tripping of the two 230 kV Hermosa-Limay transmission lines pushed the system from having a sufficient supply to a red alert level by isolating the baseload power plants in Bataan, which were supposedly available to supply power to the Luzon grid.

The Bataan plants (GNPD and GMEC) that showed recurring outages from May to June 2022 were operating on June 18, but were forced again to shut down due to the transmission line tripping. This sudden loss led to an estimated 1,200 MW of automatic load dropping in Luzon.

The Luzon grid was placed under yellow alert status again on Monday, according to the NGCP, after several baseload power plants went on forced outages again. ICSC energy transition advisor Alberto Dalusung III pointed out that this shows the underlying problem of recurring centralized generator shutdowns in the grid.

“The high power generating costs, interruptions, and the grid alert levels raised during this time highlights the vulnerability of our grid to large centralized generators. Any problem with these centralized generators can push the entire power system into a costly and vulnerable state because of the significant share of each individual centralized plant in the system,” Dalusung said.

“Our current situation emphasizes the urgent need for an energy transition based on flexible, distributed energy sources. While we acknowledge that this energy transition will not be an overnight process, we need to pick up the pace by keeping flexibility and decentralization in perspective for our country’s system planning and policy-making,” added Dalusung.

The Institute for Climate and Sustainable Cities is a Manila-based climate and energy policy group advancing climate resilience and low carbon development.

AC Dimatatac, media@icsc.ngo, +63 998 546 9788, +63 917 149 5649


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