RISING electricity demand triggered the Mindanao grid’s first red alert of the year on Monday, August 10, disrupting regional power transfers and exacerbating an ongoing supply crisis in the neighboring Visayas grid.
The National Grid Corp. of the Philippines (NGCP) issued concurrent grid warnings across both regions as capacity struggled to keep pace with demand.
In Mindanao, a spike in forecasted system demand forced the operator to place the grid under red alert from 3:00 p.m. to 4:00 p.m. and again from 5:00 p.m. to 8:00 p.m. Intermittent yellow alerts were scheduled from 4:00 p.m. to 5:00 p.m. and 8:00 p.m. to 10:00 p.m.
The surge in local consumption sharply reduced the surplus electricity Mindanao typically exports to Visayas.
Because Visayas relies heavily on power imported from Mindanao to stabilize its grid, the sudden reduction in incoming supply plunged the island group into its fourth red alert since July.
Visayas remained under red alert from 3:00 p.m. to 9:00 p.m., transitioning to a yellow alert until 10:00 p.m.
The regional shortfall was compounded by ongoing forced outages, with 26 power generation plants completely shut down and 13 others operating at derated capacities.
In total, 909.9 megawatts (MW) were offline, leaving available capacity at 2,350 MW against a peak demand of 2,276 MW.
Under NGCP protocol, a yellow alert signals that operating reserves have fallen below the threshold required to handle potential system contingencies.
A red alert indicates that supply is inadequate to cover consumer demand and grid regulation requirements, placing power distribution utilities on high risk for manual load dropping (MLD) or rotational brownouts.
While inclement weather further complicated grid operations across both regions, the grid operator has not yet confirmed if rotational brownouts were officially implemented during the peak warning hours.
