Manila, Sept. 22 -- The Visayas grid was placed under yellow alert from 4 p.m. to 8 p.m. on Tuesday due to the unavailability of several power plants and reduced capacity of others, the National Grid Corp. of the Philippines (NGCP) said.

The grid had about 2,504 megawatts (MW) of available capacity against an expected peak demand of 2,419 MW, leaving it short of the required contingency reserve, the NGCP said.

Among the plants on forced outage were Unit 1 of Therma Visayas Inc., Unit 3 of Panay Energy Development Corp., and Unit 2 of Kepco SPC Power Corp.

The 36-MW Unit 3 of Cebu Energy Development Corp. was also operating at reduced capacity, while power imports from Mindanao were below normal, the NGCP said.

The grid had 13 power pl...