In September 2025, the system-wide average supply increased by 0.5% to 20,712 MW, while demand declined by 2.9% to 13,640 MW. This resulted in a comfortable supply-demand margin of 5,194 MW, up from 4,578 MW in August 2025. Consequently, average market prices fell to PHP 3.04/kWh from PHP 4.59/kWh in the previous month—marking the lowest level recorded in the past seven months.
The expanded margin led to lower market prices across the board. In Luzon, prices dropped significantly due to higher supply and lower demand, despite increased power exports through the HVDC link. In Visayas, prices also decreased, accompanied by a reduced power import from Mindanao. Mindanao experienced a similar trend, with prices declining in line with reduced export volumes to the Visayas.
Power plants operated reliably as there were no major unplanned outages experienced, coupled with hydropower plant output boosted by the rainy season, overall market conditions were favorable for keeping prices low, contributing to the overall decrease in prices. The impact, if any, of the earthquake that occurred in Visayas on September 30, 2025, which caused multiple tripping of transmission lines and generators, shall be reflected in the October 2025 billing period.
Moreover, in terms of system-wide generation mix, renewable energy (RE) accounted for 26% of total generation. Coal-fired generation increased its share from 50.6% to 55.1%. Hydropower generation continued its upward trend, rising from 12.6% to 13.5%, due to intense rains brought about by recent typhoons. Meanwhile, the shares of natural gas and oil-based generation declined, with natural gas dropping from 22% to 17%, and oil-based generation decreasing from 0.9% to 0.5%. Solar and geothermal generation also saw slight reductions, with solar decreasing from 4.0% to 3.7%, and geothermal from 7.8% to 7.6%. Approximately 25% (2.34 TWh) of total customer transactions for the period were sourced from the retail market.
The Effective Spot Settlement Price (ESSP) for September 2025 was PHP 3.28/kWh, down from PHP 5.56/kWh in August 2025. Spot market volume represented 13.7% of total traded electricity, a decrease from 15.5% in the previous month. In line with this, the total trading amount fell from PHP 15.32 billion to PHP 8.84 billion.
Reserve Market
In the Reserve Market, zonal prices for Regulation Reserves increased in both Luzon and Mindanao. However, prices for all other reserve commodity types across most regions declined, except for Dispatchable Reserves in Visayas. System-wide reserve market transactions amounted to PHP 4.68 Billion, down from PHP 5 Billion in August 2025.
In Luzon, overall trading amounts declined due to a decrease in spot market exposure. Regulation Reserves increased in volume and cleared at higher prices ranging from PHP 3 to 9 per kWh, primarily from battery and hydro sources, although their spot share declined. Contingency Reserves fell, reflecting both lower prices and a reduced spot share, clearing at PHP 0.9 to 1.2 per kWh from oil and coal plants. Dispatchable Reserves also saw lower prices and reduced spot exposure, clearing between PHP 0.4 and 1.9 per kWh from oil-based generators.
In Visayas, a mixed trading outcome was observed. Regulation Reserves declined due to lower zonal prices and reduced spot market share. Contingency Reserves also decreased in price while maintaining consistent spot exposure. Conversely, Dispatchable Reserves increased in price despite a slight decline in spot participation. Regulation Reserves cleared at prices ranging from PHP 6 to 25 per kWh, Contingency Reserves at PHP 3.8 to 5.5 per kWh, and Dispatchable Reserves at PHP 7 to 9 per kWh, largely from oil and coal plants.
In Mindanao, overall trading amount declined. Regulation Reserves dropped due to lower spot exposure, even as output from battery facilities cleared at prices ranging from PHP 23 to PHP 25 per kWh. Contingency Reserves also decreased, with clearing prices between PHP 0.3 and 3.3 per kWh, sourced mainly from battery and coal facilities. Dispatchable Reserves experienced a sharp decline, with lower zonal prices and consistent spot exposure, clearing at PHP 0.9 per kWh from oil-based plants.
