Luzon grid threatened with rolling brownouts due to thin power reserve

by Myrna Velasco – April 10, 2017, 10:00 PM

from Manila Bulletin

Luzon grid inched close into having rolling brownouts on Monday as system operator National Grid Corporation of the Philippines (NGCP) raised power system condition to “red alert status” due to negative reserves.

Power interruptions were anticipated by 2:00 to 3:00 p.m., but the system held so the “red alert” level was brought down to “yellow alert” again by 3:00pm.

That incident though had totally negated guarantees of stable electricity service in Luzon grid just sounded off recently by both NGCP and the Department of Energy.

Early morning of Monday, NGCP already raised “yellow alert” condition or “near brownout scenarios” with the reserve level precipitously plummeting to 208 megawatts at morning peak in demand – initially that had been from 9:01am to 4:00pm until it escalated to threatening brownout forecasts around noontime.

Red alert portends insufficiency of power supply or zero reserves, so rotating brownouts had to be suffered by consumers; while yellow alert is that state in power system when there would be no enough reserves to take on capacity loss if there would be additional power plant forced outages or trippings.

As of 7:30 a.m. on Monday, NGCP indicated that the projected level of reserves were at 208MW at11:00 a.m.; 326MW at 2 p.m. peak; and 826MW by 7 p.m. peak demand period; then it went extremely critical as temperatures rose during the day.

The DOE has reported that Luzon grid suffered capacity loss of 2,584 megawatts following the swarm of earthquakes that afflicted Batangas (hub of power plant developments) on Saturday (April 8).

Initial NGCP data showed that Monday’s system capacity was at 9,515MW; while peak demand had been estimated at 8,926MW. The earthquake-plagued generating plants included modules 50 and 60 of the San Lorenzo gas-fired facility; the San Gabriel and Avion gas plants; Ilijan Block B; Calaca unit 2, Makiling-Banahaw and GN Power plants that had compounded the forced outage suffered at Pagbilao unit 2. The department said the earthquake incidents “affected the power supply and services of various provinces in Luzon, including Batangas, Laguna, Quezon, Ilocos Sur, La Union, Pangasinan, Bataan, Tarlac, and Nueva Ecija.”

NGCP similarly noted that the Batangas-San Lorenzo lines 1 and 2 “were affected with an initial report on a toppled tower, and the switchyard at the San Gabriel natural gas power plant was also damaged due to the earthquake.”

Upon declaration of electricity system’s inauspicious “yellow alert” condition, Manila Electric Company (Meralco) announced that it “began asking ILP (interruptible load program) participants if they are available to deload.”

Meralco Vice President Lawrence S. Fernadez emphasized that as early as 8:30 a.m., the utility firm already secured go-signal from a number of ILP participants that have been ready to deload close to 200MW capacity.

“On the confirmed ILP participants, we have 135 accounts that said they are available to deload, with an aggregate deloading capacity of 196MW,” he stressed.

With the latest earthquake incidents staring energy officials and planners in the face, DOE Secretary Alfonso G. Cusi said the department’s Energy Policy and Planning Bureau “is drafting a policy on resiliency planning and programs in the energy industries which include power, upstream and downstream oil, energy resource development, and renewable energy sectors.”