AboitizPower Highlights Sharp Rise In Philippine Summer Demand As Cooling Use Surges And Renewable Output Declines

Peak electricity demand in the Philippines continues to rise sharply during the country’s hottest months, driven largely by increased use of cooling systems and declining output from some renewable energy sources.On a typical day, electricity consumption peaks three times — late morning around 11:00 am, mid-afternoon at about 2:00 pm, and again in the evening at around 7:00 pm. But over the course of a year, the highest demand is consistently recorded during the summer season, when temperatures surge and households and businesses depend heavily on air conditioning.

Data from the Independent Electricity Market Operator of the Philippines (IEMOP) underscores this trend. The country’s peak demand in 2025 hit 19,011 megawatts in April, the highest for the year, followed by 18,767 megawatts in May. By contrast, peak demand in the cooler months of January and February 2026 dropped to 15,717 megawatts and 16,271 megawatts, respectively. The difference of 3,294 megawatts between April 2025 and January 2026 represents a 20.96% increase in power use during the hotter month.

Energy experts note that demand typically rises by around 100 megawatts for every one degree Celsius increase in temperature — a rule of thumb frequently cited by a former energy secretary. This puts additional pressure on the grid exactly when supply from certain renewable sources dips.Hydropower, for instance, sees a significant decline during the dry season. Data from the National Grid Corporation of the Philippines (NGCP) shows that hydroelectric generation was lowest from March to May 2025, producing 2,747,921 megawatt-hours.

Its strongest output came from September to November, reaching 4,083,920 megawatt-hours. This means roughly one-third of hydroelectric production is lost during the hot months, when the system needs it most.Solar power performs differently. With longer days and stronger sunlight, solar generation reached its peak from March to May 2025, totaling 1,385,122 megawatt-hours. But despite its summer surge, solar output remains limited by its intermittency.

Without energy storage systems, solar power disappears at night and drops during cloudy conditions, resulting in capacity factors of only 18% to 20% in 2024 and 2025. While battery storage can address these gaps, it adds substantial cost to solar projects.Even at its highest levels, solar energy is unable to fully compensate for the hydroelectric losses during the same period. The decline in hydro output was about 2.45 times greater than the gains from solar, highlighting the need for other dependable power sources during peak demand months.

Coal plants have been filling much of that gap. IEMOP reported that coal generation increased significantly during evening peak hours and surged during the April and May 2025 billing periods. Geothermal plants, another baseload source, remained stable throughout the year and contributed an average of 8% to total power generation in 2025, ranging from 6.79% in September to 8.9% in January.

These trends underscore the importance of maintaining a diverse energy mix. While renewable energy continues to expand, its intermittency means that the grid still requires sufficient baseload and mid-merit capacity to ensure stability. IEMOP has stressed that increasing renewable energy installations must be paired with reliable supporting sources to maintain a balanced power system.

The rapid growth of distributed energy systems, such as rooftop solar and net metering, also places new demands on the grid. These developments require accelerated upgrades in transmission and distribution infrastructure to manage changing power flows and increased connectivity. At the same time, the energy sector faces pressure to strengthen supply chains for renewable energy equipment, storage technologies, and grid components, while ensuring adequate fuel supply for coal and gas plants. E

fforts to explore and develop local energy resources, including geothermal projects backed by the Philippine Geothermal Resource De-Risking Facility, are becoming increasingly critical.Industry leaders say that balancing supply and demand — while advancing the country’s clean energy transition — remains a complex challenge.

It requires close coordination among power generators, transmission and distribution companies, regulators, policymakers, investors, and consumers. As summer temperatures continue to push the country’s electricity system to its limits, experts warn that developing a resilient, well-diversified energy mix has never been more essential.