Spot market electricity prices rose in August as demand picked up and supply declined due to plant outages, according to the Independent Electricity Market Operator of the Philippines (IEMOP).

“In August, the system-wide average supply dropped by 0.7 percent to 20,611 megawatts (MW), due to widespread plant outages. Demand rose by 1.7 percent to 14,052 MW, pushing market prices up to P4.59 per kilowatt-hour (kWh) from P3.99/kWh in July,” IEMOP Vice President for Trading Operations Isidro E. Cacho Jr. said on Wednesday.

Cacho noted that “in Luzon, despite higher demand and supply, prices drop slightly, even with more power exports to Visayas through HVDC.”

In the Visayas, prices surged “due to outages of several coal plants and the shutdown of biomass facilities due to the end of the milling season,” which triggered Yellow Alerts on 1, 4, and 5 August.

In Mindanao, outages of coal units also caused a Yellow Alert on 1 August, while “powerplants with costlier fuel clearing the market” pushed prices higher.

On the generation mix, Cacho reported that renewable energy contributed 26 percent of total generation. Natural gas rose to 22 percent from 21 percent, while coal fell from 54.1 percent to 50.6 percent and geothermal from 8.1 percent to 7.8 percent.

Solar expanded from 3.3 percent to 4 percent, oil-based from 0.4 percent to 0.9 percent, and hydro jumped to 12.6 percent from 10.5 percent, boosted by rains from typhoons and the southwest monsoon.

For the month, IEMOP said around 23 percent or 2.28 terawatt-hours of total customer transactions were sourced from the retail market.