The Visayas power grid was placed under a yellow alert again Thursday as the unexpected shutdown of a major coal-fired plant further depleted the region's energy reserves.

The National Grid Corporation of the Philippines (NGCP) announced that the yellow alert status for the Visayas grid is in effect from 3 p.m. to 10 p.m. following the tripping of the 103-megawatt KEPCO SPC Power Corp. Unit 2. 

A yellow alert indicates the grid's operating margin is insufficient to meet contingency requirements, although it does not automatically trigger immediate power outages.

The grid's available capacity stood at roughly 2,532 megawatts against a projected peak demand of 2,388 megawatts. According to the NGCP, 13 power plants have been on forced outage since early May, with several others offline from previous years, and 14 plants operating at reduced capacity.

This resulted in a total unavailable capacity of approximately 1,006.2 megawatts across the region.

The loss of the KSPC unit compounded the severe supply constraints caused by the ongoing forced outages of major baseload facilities, specifically Units 1 and 2 of Therma Visayas Inc. and Unit 3 of Panay Energy Development Corp.

The recurring power strain has significantly affected local businesses. Micro, small and medium enterprises (MSMEs) are bearing the brunt of the crisis, facing productivity losses and the high costs of running emergency fuel generators without local government subsidies.

In response to the tight supply margins and volatile global fuel costs, utility provider Visayan Electric recently announced a rate increase of P0.31 per kilowatt-hour, bringing May residential electricity rates to 12.88 pesos per kWh.