NGCP clarifies “red alert” status, explains load curtailment
NGCP issued a “red alert” notice to its Luzon grid customers due to insufficient power supply brought about by the unexpected nature of the unplanned outages of certain power plants. During the peak hours of 2:00 P.M. to 4:00 P.M. on Friday, May 16, the system indicated that available capacity was at 8,139 MW while demand was at 8,403 MW.
The unavailability and/or the reduced capability of certain power plants led to the situation where contingency reserve was zero because of a generation deficiency.
Rotating brownouts in Luzon were expected on Friday because of the generation-related deficiency. The specific affected areas and the duration and schedule of brownouts per area were determined by the local distribution utility. The supply situation normalized once the unavailable capacities or the plants on shutdown or running on limited capabilities were back and synchronized to the grid and the demand receded.
It is NGCP’s obligation under the law and its franchise to ensure that the grid operates at an optimum level with due consideration for safety, security and reliability. NGCP is closely monitoring the situation and continues to be in close coordination with the Department of Energy (DOE) to ensure that all the capacities available to the grid are dispatched efficiently.
NGCP does not control power supply but during periods of generation deficiency, it does its best to mitigate the situation by implementing the grid-wide power load curtailment to maintain the grid’s security and reliability.
NGCP, as System Operator, issues Grid Operation Notices to grid users.
“Red alert” refers to the system condition when the contingency reserve is zero or a generation deficiency exists, while a “Yellow alert” is a system condition where the total of all reserves is less than the capacity of the largest plant online, which for the Luzon grid, is 647 MW.
When system reserves are more than sufficient to meet the reserve requirements of the grid, the system is considered to be under normal condition.The system alert, and the corresponding power curtailment, if any, is lifted once demand recedes or once there is enough available capacity coming into the grid from the power plants.