The forced outage of the 668-megawatt Dinginin coal-fired plant, a joint venture of the Ayala-Aboitiz group, has caused short-term electricity service disruption or brownout to more than 450,000 customers of Manila Electric Company (Meralco) in Manila and adjacent provinces on Wednesday.
According to Meralco Vice President Joe Zaldarriaga, the areas affected had been those in Santa Ana, Malate, Binondo and Tondo in Manila; Malolos, Baliwag, San Miguel and Marilao in Bulacan; Silang, Tagaytay, General Trias, Tanza, Naic and Rosario in Cavite; Lucena, Candelaria and Tiaong in Quezon; and Calamba and San Pablo in Laguna.
In an advisory to power industry stakeholders, system operator National Grid Corporation of the Philippines (NGCP) stated that the Dinginin plant tripped while having a load of 520MW as of 9:24am on Wednesday.
Meralco subsequently indicated that the technical glitch at Dinginin plant affected its feeders for a total load of 208MW, prompting automatic load dropping (ALD) at its load network that then caused the 16-minute brownout for its customers. Power was restored at 09:58 am.
The giant power utility firm advised its customers that “if you have suddenly experienced a power interruption, please expect power to return in 10-15 minutes.” And while the brownouts had been momentary, it still caused inconvenience to the areas affected.
There is no statement yet from the Department of Energy (DOE) as to the cause of the recurring technical problem hounding Dinginin plant -- although technical experts noted that since it is a new generating facility, it might still be at its "birth pains phase” yet when it comes to its commercial operations.
As explained by Meralco Vice President Lawrence S. Fernandez, for a power utility to be plunged into ALD, that typically entails that “there is not enough fast-acting reserve to make up for the tripping of a large plant, hence, the recourse of the grid is to drop loads.”
He specified that “ALDs can happen even when there is sufficient supply, even during night time,” or on a timeframe when demand is conventionally low.
On March 26 this year when Luzon grid was placed on "yellow alert condition", the tripping of the Dinginin plant as well as the forced outages of other power generating units had likewise been traced as the triggering factor.
The energy department and Energy Regulatory Commission (ERC) had consistently warned of unplanned outages of power plants that may cause power interruptions during the summer months and on election day, May 9.
On account of that, the commitment of power companies is to strive to make their capacity available at optimum level. However, if electricity service cut-off cannot be avoided, the voting precincts and canvassing centers shall be spared from brownouts.