Higher ancillary services (AS) costs pushed up transmission rates in August 2025, an increase reflected in the September bills of end consumers, grid operator National Grid Corp. of the Philippines (NGCP) said Wednesday.
The overall average transmission rate for the August billing period rose 7.09 percent to P1.4171 per kilowatt-hour from P1.3233 per kWh in July, the company said.
AS charges climbed to P0.6659 per kWh in August from P0.5872 per kWh in July. AS rates are pass-through costs for power supplied by AS providers during a supply-demand imbalance.
NGCP spokesperson Cynthia Perez Alabanza said market forces pushed up the rates.
“Because it’s market-driven, the rules on supply and demand will apply,” Alabanza said.
“But it’s not always going up. There are months, like last month, where the prices in the reserve market went down,” she said.
AS charges are remitted directly to generating companies with bilateral contracts with NGCP and to the Independent Electricity Market Operator of the Philippines (IEMOP) for AS sourced from the reserve market.
NGCP does not earn from AS and does not benefit from changes in AS prices.
Meanwhile, NGCP’s transmission wheeling rate—the fee for delivering power through its grid—barely changed, inching up by P0.0047 per kWh to P0.5970 per kWh in August from P0.5923 per kWh in July.
“For August 2025, NGCP charges only about P0.5970 per kWh for its transmission service, while ancillary services remain the biggest component of transmission-related costs,” the grid operator said.
Transmission wheeling rate accounted for 3.72 percent, while ancillary services charges captured 5.43 percent of the consumer’s electricity bill.
NGCP said it has implemented necessary preparations and precautions to minimize the impact of Tropical Depression Mirasol on transmission operations and facilities.
Preparations include ensuring the reliability of communications equipment, the availability of hardware materials and supplies for the repair of damaged facilities and the positioning of line crews in strategic areas to facilitate immediate restoration work.
The company’s Integrated Disaster Action Plan (IDAP) prescribes these and other procedures to ensure the readiness of all power transmission facilities expected to be affected by the weather disturbances.
