Mindanao power grid hit by alternating alerts as plants fail, demand spikes

The Mindanao grid faced mounting pressure on Tuesday as the National Grid Corporation of the Philippines (NGCP) declared alternating red and yellow alerts, signaling critical supply conditions. According to NGCP advisories issued at 1:20 p.m., a red alert was set to remain in effect from 1:00 p.m. to 4:00 p.m., followed by further alerts through the evening hours as demand peaked.

The dual pressures of an unexpected plant outage and rising system demand created a tight operating margin for the region's power supply. Red alerts indicate that available generating capacity has fallen below the minimum required reserve, heightening the risk of rotating blackouts if demand continues to climb or additional generation becomes unavailable.

The Mindanao grid, which supplies power to the southern Philippines, has faced recurring supply challenges during peak demand periods. The Tuesday incident underscored the region's vulnerability to generation disruptions during periods of high consumption.

The NGCP did not immediately disclose when normal operating conditions were expected to resume. Power utilities typically begin relaxing alert status once sufficient generation capacity returns online or demand moderates during evening hours.