MANILA (UPDATE 3) - The National Grid Corp of the Philippines again put the Luzon and Visayas power grids on alert on Friday, warning of possible brownouts, as reserves remained thin.

The NGCP said the following alerts will be in effect.

LUZON GRID

Red Alert 

3 p.m. - 4 p.m. 

6 p.m. - 10 p.m.  

Yellow alert

12:nn - 3 p.m. 

4 p.m. - 6 p.m. 

10 p.m. - 11 p.m.

It said that 19 power plants remain on forced outage, while 3 are running on derated, or lower capacities, for a total of 2,284.3 MW unavailable to the grid.

The available capacity in the Luzon grid is at 13,594 megawatts, while peak demand is expected to hit 13,127 MW.

Meralco said it has already asked big power consumer in its interruptible load program (ILP) for their de-loading commitments.

The company said it is ready to implement manual load dropping or rotating brownouts to manage the system.

"We also reiterate our call to the public to continue energy conservation and efficiency practices to help manage the overall demand," Meralco said 

VISAYAS GRID

Red Alert

1 p.m. - 8 p.m.

Yellow Alert

8 p.m. - 9 p.m.

ROTATING BROWNOUTS

The NGCP said it may also implement rotating brownouts from 5 p.m. to 6 p.m. in the following areas to maintain the integrity of the power system:

• CENECO (parts of Negros Occidental)
• NOCECO (parts of Negros Occidental)
• NORECO II ((parts of Negros Oriental)
• SOLECO (parts of Southern Leyte)
• LEYECO II (parts of Leyte)
• LEYECO V (parts of Leyte) 
• SAMELCO (parts of Samar) 
• ESAMELCO (parts of Eastern Samar) 
• NORSAMELCO (parts of Northern Samar)
• MORE (parts of Iloilo City)
• AKELCO (parts of Aklan)
• ANTECO (parts of Antique)
• CAPELCO (parts of Capiz)
• ILECO II (parts of Iloilo Province)
• ILECO III (parts of Iloilo Province)
• GUIMELCO (parts of Guimaras)

It said the schedule may be canceled if the system condition improves, such as if actual demand falls below projections.

Eighteen power plants are on forced outage, while 10 others are running on derated or lower capacities, for a total of 757..7MW unavailable to the grid, the NGCP said.

The available capacity in the Visayas is at 2,484MW, while peak demand is at 2,504MW.

The NGCP also advised on unscheduled power interruption in parts of Negros Occidental Friday, April 19 affecting the CENECO (Sum-ag and Lag-asan Substations) and NOCECO (Valladolid, San Enrique and La Carlota Substations).  

This is because of the tripping of the  Bacolod-San Enrique 69kV line at 2:18 a.m.

A red alert status means rotating brownouts can be expected as power supply is insufficient to meet consumer demand and the transmission grid’s regulating requirement.

A yellow alert means brownouts are possible because the power grid's operating margin is insufficient to meet the transmission grid’s contingency requirement.

This is the fourth straight day this week that the NGCP has issued alerts because of thin power reserves.