ASIDE from transmission issues, stability of power supply in the Visayas grid is also dependent on generation, an official of National Grid Corp. of the Philippines (NGCP) said.
Lawyer Leonor Felipa Cynthia Alabanza, spokesperson and head of Corporate Communications and Public Affairs of NGCP, said the recent restoration of the Ormoc High Voltage Direct Current (HVDC) Converter Station only addressed woes on transmission.
Meaning, the transmission utility still does not have full control over the supply, Alabanza told VoxPop Bacolod.
"If there is a problem with supply in the Visayas, we can import power from generation plants in Luzon, if available," she said.
"However, when Luzon is also experiencing supply issue, there may not be excess power to export to the Visayas," Alabanza added.
The Department of Energy (DOE) earlier said the damage caused by the magnitude 6.3 earthquake in Leyte last July to the HVDC facility of the NGCP resulted to power deficiency in the Visayas grid.
The damage to the facility, which controls connection from Luzon to Visayas, has cut off about 400 megawatts (MW) supply coming from Luzon for several weeks.
The grid was placed under "yellow alert" status, a situation where there is less power reserve than the requirement, causing rotational brownouts throughout the Visayas regions, including Negros.
After the restoration last September 7, the NGCP said power interruptions may still occur if issues in generation and distribution will arise.
Generation involves power plants while distribution concerns distribution utilities like the Central Negros Electric Cooperative, Northern Negros Electric Cooperative, and Negros Occidental Electric Cooperative catering to electric consumers in the province.
Alabanza said that oftentimes, the Visayas grid is on "yellow alert," where power interruptions may occur due to near zero excess supply, or "red alert," where brownouts are imminent.
This computation is based on an assessment of the supply from power plants in the Visayas and demand profile of the users in the island.
Fortunately, the usage profile of Luzon is compatible with that of Visayas, Alabanza said.
"Luzon's use peaks at 2 p.m. when Visayas does not need power. By 7 p.m. when Luzon is over its peak, it is Visayas which enters peak use and is able to draw power from the former when needed," she added.
