Trades at the Wholesale Electricity Spot Market (WESM) were suspended on Thursday as Luzon and the Visayas were placed under red and yellow alert status.
The Energy Regulatory Commission (ERC) said the trade suspension resulted in part from the emergency shutdown of the country’s largest power plant.
ERC rules allow trade suspensions during red alerts as power companies remain under obligation to offer their uncontracted capacity even during red alerts.
Monalisa Dimalanta, ERC chairman, said the conditions set in the suspension mechanism were met on Thursday.
Both the Luzon and Visayas grids were under red and yellow alert conditions as of 9 a.m. Thursday as 45 power plant units were either on forced outage or compelled to de-rate, resulting in the loss of 3,078.6 megawatts capacity.
The yellow alert was up in Luzon initially from 12 p.m. to 1 p.m., 5 p.m. to 6 p.m. and 10 p.m. to 12 midnight. This turned red from 1 p.m. to 5 p.m. and 6 p.m. to 10 p.m. as 18 power plant units and three others de-rated, resulting in the unavailability of 2,525.5 MW in the region.
A yellow alert was declared in the Visayas from 12 p.m. to 2 p.m., 4 p.m. to 6 p.m. and 7 p.m. to 10 p.m. but raise to red alert from 2 p.m. to 4 p.m. and from 6 p.m. to 7 p.m. as 21 power plants were on forced outage and three others de-rated, resulting in capacity loss of 553.1 MW.
According to the National Grid Corporation of the Philippines (NGCP), the available capacity in Luzon Grid stood at only 13,531 MW compared to a peak demand of 13,597 MW. The available capacity in the Visayas was only 2,5,88 MW against peak demand of 2,537 MW.
Year-to date, the NGCP said red alerts have been raised in the Luzon grid seven times and in the Visayas eight times. Yellow alerts for the period were raised 20 times in Luzon, 22 in the Visayas and twice in Mindanao.
Joe Zaldarriaga, Manila Electric Co. spokesperson and head of corporate communications, said the interruptible load program kicked in by 1 p.m. Thursday to help secure the load in the grid.
“We have secured commitments from big-load customers under ILP to de-load more than 300 MW and help ease demand. We are also ready in the event the implementation of manual load dropping or rotating power interruptions will be needed as part of our responsibility to manage the system,” Zaldarriaga said.
The DOE said tight power supply conditions have persisted due to sustained high peak demand in both the Luzon and the Visayas as certain areas continue to experience extreme temperatures and high heat indices.
The agency said with the projected heat index remaining elevated in select areas, peak demand will likely remain above forecaste levels throughout the remainder of May.
The DOE noted that in Luzon, power interruptions lasted 1 hour and 14 minutes at most in mid-April and no more than hour and 18 minutes a few days later. It said power interruptions were even shorter in most areas, adding that in Visayas and Mindanao, there were no actual power interruptions.
“Red and yellow alerts need not result in actual power interruptions if the power demand can be correspondingly reduced to respond to the decrease in power supply,” said Energy Secretary Raphael Lotilla, in a statement.
