The National Grid Corporation of the Philippines (NGCP) yesterday called on the need for a whole-of-industry approach, including better energy resource planning, in addressing per island power needs.
The appeal was issued following the power outage due to tripping of multiple power plants which isolated Panay island from the rest of the Visayas grid on Tuesday.
“The unscheduled maintenance shutdowns of the largest power plants in Panay island was the primary cause of the power interruption. We emphasize the need for improved planning to ensure sufficient generation per island, with a well-balanced mix of fuels and technology,” said NGCP, in a statement.
The tripping of three of the largest power generating units and the planned maintenance shutdown of some plants caused a loss of a total of 656 megawatts (MW) in-island generation to the Panay sub-grid.
NGCP said maintenance shutdowns and deration of plants outside the Department of Energy’s (DOE) approved Grid Operating and Maintenance Program also contributed to the lack of power supply.
“We will be restoring loads conservatively, by matching loads to restored generation, to prevent repeated voltage failure. NGCP is ready to transmit power once it is available. The people must understand that we can only transmit power, we do not generate power,” the company said.
NGCP in a May 11, 2023 letter to the Iloilo City government highlighted the need to conduct more resource optimization planning by policy makers, to ensure solutions to power system concerns are approached from all angles and the most efficient ones prioritized.
Given the configuration of the Panay sub-grid and its dependency on variable energy sources in Negros when it loses internally generated power, NGCP also noted the need to provide sufficient baseload power sources to stabilize the system.
NGCP said the Cebu-Negros-Panay Stage 3 project is a contributing solution.
As of 4 p.m. yesterday, the company said 200.1 MW is being served by Panay power plants, augmented by 47.5 MW from sources elsewhere in the Visayas, for a total of 243.5MW served loads.
However, NGCP said t the grid needs about 300 MW to stabilize and is awaiting the remaining plant with a 135 MW capacity to synchronize back to the grid.
The DOE said NGCP as system operator of the national grid, is in a position to immediately coordinate with power plants to ensure their respective unit protection and control settings will not cause grid instability that could lead to black outs.
“NGCP is in a position to anticipate system disturbance such as what happened yesterday, which unfortunately resulted in the isolation of Panay from the rest of the Visayas grid due to the simultaneous tripping of power plants that caused multiple power interruption affecting other power plants and distribution utilities (DUs),” said Energy Undersecretary Rowena Cristina Guevara, in a separate statement.
The DOE added it continuously coordinates with the NGCP and affected power plants and DUs on the status of the power plants, including the estimated timeline for the restoration of power supply.
The Energy Regulatory Commission (ERC) said it is working in coordination with both the DOE and NGCP in addressing the power outage affecting the Panay Sub-grid particularly customers of four electric cooperatives and one DU.
“To enhance communication and keep consumers better informed during this situation, we have requested the NGCP to increase the frequency of updates provided to the public. Instead of the regular four-hour updates, NGCP has complied and started to provide hourly updates on their Facebook pages. We have also directed NGCP to include information on the status of ongoing restoration efforts,” said Monalisa Dimalanta, ERC chairperson, in another statement.
