As of 1:30 p.m., the grid had an available capacity of 2,566 megawatts (MW) against a peak demand forecast of 2,389 MW.
NGCP said 19 power plants were on forced outage, while five other plants were operating at reduced or derated capacities. These outages resulted in a combined 755.1 MW of capacity unavailable to the grid.
Of the plants on forced outage, 19 were reported in August, four have been offline since July, one since June, two since January, one since 2025, and another since 2024.
NGCP also cited a 106-MW increase in the forecasted Mindanao demand for 6 p.m. as an additional factor behind the declaration.
A Yellow Alert is issued when the available operating margin is not enough to meet the transmission grid's required contingency reserve.
The alert covers the anticipated peak-demand period from 5 p.m. to 9 p.m. Monday.