BY GEROME DALIPE IV
ILOILO City – Recurring power outages on Panay Island and the inconveniences these brought have caused public frustration.
But the power tripping also causes unthinkable damage to the power generators.
Lawyer Jun Cabalhug Jr., Global Business Power (GBP) first vice president and Panay site head, said trends in their Supervisory Control and Data Acquisition (SCADA) and Distributed Control System (DCS) showed their two power generator units in Barangay Ingore, La Paz district, tripped off as they could barely absorb the power instability from the grid.
“Nobody knows what happens behind the scenes and the struggles we experience. Nobody want blackouts. Everybody suffers. We are doing our best. We only have one door, and it is still half-open,” Cabalhug told reporters.
He was referring to the Visayas grid, particularly the Panay-Negros Grid Interconnection between E.B. Magalona, Negros Occidental, and Barotac Viejo, Iloilo.
The Visayas grid is one of the three main power grids in the Philippines, alongside the Luzon and Mindanao grids. It covers the Visayas region, which includes the islands of Panay, Negros, Cebu, Leyte, and Samar, among others.
In his presentation during the energy forum at the city hall, an emotional Cabalhug said the March 1 blackout was caused by the tripping of units 1 and 2 with a load of 79 megawatts (MW) per unit.
The tripping of the two power plants operated by GBP subsidiary, Panay Energy Development Corp (PEDC), was triggered by the activation of its protection when Unit 3 shut down and the grid voltage dipped down to 80 kilovolts (kV).
“The tripping of PEDC unit 3 last March 1, 2024, with a load of 125MW, was caused by an internal problem due to the premature failure of the Gear of the Air preheater motor,” said Cabalhug. “If only our grid were stable and we could just get some contingency reserves or online capacity, our generators would be able to absorb it,” he said.
Cabalhug recommended the implementation of zonal allocation of contingency reserves to maintain sufficient spinning reserves during the occurrence of abnormalities.
He also called for the immediate implementation of voltage stability or correction devices projects by the National Grid Corporation of the Philippines (NGCP) to avert uncontrolled tripping of voltage-sensitive loads in the plant.
The Visayas grid is interconnected with the Luzon and Mindanao grids through several high-voltage direct current (HVDC) transmission lines managed and operated by NGCP, which oversees the transmission of electricity across the grid.
The Visayas grid faces challenges such as ensuring a stable power supply, integrating renewable energy sources, and addressing transmission constraints.
Mayor Jerry Treñas convened on Thursday, March 7, officials from the energy sector, local government units, and the business community and discussed the power situation on Panay Island.
MORE Electric and Power Corporation (MORE Power) president and chief executive officer Roel Castro said existing limitations of the Panay Grid make it more susceptible to grid blackouts.
These limitations include insufficient power supply, inadequate protection coordination settings between NGCP, power plants, and distribution utilities, and delayed completion of the Cebu-Negros-Panay Interconnection, which limits the capacity of power import of Panay from the Negros grid through the existing 138kV Negros-Panay submarine cable, resulting in long-duration Panay grid blackout.
Castro said the ancillary services or standby reserve of NGCP for the Visayas from Cebu could not augment in Panay during a blackout due to the absence of an N-1 or alternate grid connection on Panay Island.
He said the short-term solutions to the present situation include the completion of the Cebu-230kV Cebu-Negros-Panay (CNP) backbone project stage 3, which could import power from the Mindanao Luzon grid interconnection using the 230kV Transmission Line.
He also stressed that NGCP should implement the Undervoltage Load Shedding (UVLS), which will serve as protection coordination among power plants, the grid operator, and electric utilities to eliminate under-voltage.
Castro said the long-term solution includes the planned Luzon-Mindoro-Panay grid interconnection, which would significantly improve the reliability of the Panay Grid.
Likewise, he said the Negros grid will have the capability to import additional capacity from the Luzon Mainland Grid through the Panay interconnection.
Key officials from the energy sector attended the meeting, including the power transmission operator NGCP, the Department of Energy (DOE), MORE Power, PEDC, Palm Concepcion Power Corporation (PCPC), and Independent Electricity Market Operator of the Philippines Inc. (IEMOP).
The much-awaited Cebu-230 kV CNP backbone project stage 3 is now 97.44 percent complete, the DOE reported. It is set to be fully finished by the end of March 2024. /PN
