Manila, Aug. 12 -- Red and yellow alerts are again issued for the Visayas and Mindanao grids on Wednesday as several power plants remain unavailable.

The National Grid Corporation of the Philippines, in an advisory, said the red alert for the Visayas grid is between 4 p.m. to 8 p.m., while a yellow alert is up between 1 p.m. to 4 p.m. and 8 p.m. to 10 p.m.

This, as available capacity is seen to be around 2,153 megawatts (MW) while peak demand is projected to hit 2,394MW.

NGCP issues yellow alert when a grid's operating margin is short against contingency requirement while a red alert is issued when the supply is not enough to meet both the demand and the grid's regulating requirement.

The Visayas grid currently has limited supply s...