Last Friday, 15th of May 2026, the National Grid Corporation of the Philippines (NGCP) announced that yellow and red alerts will be issued for the Luzon and Visayas grids from the afternoon to evening. The sudden alerts were primarily caused by the outages of key power plants in the country, and the increasing demand for electricity amidst boiling hot temperatures.

   Based on the forecast of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), most regions in Luzon and the Visayas experienced extremely hot and dry conditions. Average temperatures ranged from 34°C to 38°C, posing a dangerous risk to Filipinos exposed to the sun. 

  Extreme weather conditions may lead to numerous heat-related illnesses, such as heat exhaustion and heatstroke, according to the World Health Organization (WHO). As a result, many Filipinos consume more power for air-conditioning units to mitigate the effects of the weather. Thus, demand exponentially increases, which power grids cannot sustain.

     At an available capacity of 13,508 megawatts (MW), the Luzon grid faced a demand of 13,881 MW, a load it cannot efficiently sustain for a prolonged period of time.

     “The extension of the red and yellow alerts is due to the tripping of GNPD Unit 1, resulting in the loss of 668 MW and further aggravating the supply deficiency,” the NGCP stated.

     Furthermore, 17 power plants experienced forced outages since May, according to the NGCP. In the meantime, one plant has been out since April, three since March, one since February, and an additional three since January. With this in mind, yellow and red alerts across Luzon and the Visayas were seen as necessary to prevent nationwide blackouts.

What is the differentiation between a Yellow Alert and a Red Alert?

  A yellow alert means that power plants are producing significantly less electricity than the grid’s contingency requirement. On the other hand, a red alert occurs when generation falls below demand, resulting in rotational brownouts or power outages.

     More than 540,000 of Meralco’s customers have been affected by the power grid interruptions in areas of Bulacan, Cavite, Laguna, Metro Manila, Quezon, and Rizal.

  Department of Energy Secretary Sharon Garin said that the public deserves “a complete accounting of incidents of this magnitude,” and she added that they will “ensure that all operational, technical, and compliance dimensions are fully examined and that appropriate actions are taken when warranted.”

  As of May 16, 2026, the yellow and red alerts were lifted. The power grids in Luzon and Visayas are back to normal and under relatively normal conditions based on the NGCP’s data at 6:00 A.M.

  The NGCP clarified that the power grids will remain stable throughout the weekend. Moreover, the Department of Energy (DOE) stated that it is coordinating with generation companies, industry stakeholders, the NGCP, and others to guarantee grid stability.