The growing use of rooftop solar power is prompting the National Grid Corporation of the Philippines (NGCP) to seek a government policy requiring the registration and monitoring of privately installed systems connected to the grid.
NGCP Assistant Vice President and head of public relations Cynthia Perez-Alabanza said that the grid operator currently lacks complete information on the volume of rooftop solar installations, making it difficult to accurately account for their impact on electricity supply.
Unrecorded solar capacity, according to Alabanza, could become a grid management concern, particularly when sudden changes in weather cause solar generation to drop sharply.
“If there are enough solar installations that NGCP does not know about and there is a sudden cloud cover, it’s as if a large plant connected to the grid falls and the NGCP has to manage,” she said.
NGCP introduced a voluntary data-sharing initiative with distribution utilities and electric cooperatives last year to improve its information on rooftop solar installations.
Alabanza, however, said a mandatory government policy would provide a more reliable basis for long-term grid planning.
The increasing contribution of solar power has also changed electricity demand patterns in the Visayas, with peak demand moving from around 2 p.m. to 4 p.m., as solar generation starts to decline later in the day.
Alabanza proposed that government facilities such as schools and barangay halls could be prioritized for solar installations because their electricity consumption generally occurs during daylight hours.
“Personally, I think solar for government offices is a good starting point for solar. Maybe that’s a better immediate application rather than in bulk,” she said.
Alabanza added that NGCP is prepared to provide technical data and recommendations if the government reviews the country’s energy generation mix, particularly on managing fluctuations from intermittent renewable sources.
Meanwhile, NGCP Assistant Vice President for Visayas Systems Operations Neil Martin Modina said solar accounted for 10.3 percent of the Visayas power supply as of May 14.
Coal remained the largest source at 43.5 percent, followed by geothermal power at 36.5 percent.
Modina said future energy mix projections should be assessed on a per-island basis to account for differences in grid conditions and maintain system balance.
The assessment is also relevant to the government’s renewable energy targets under the National Renewable Energy Program, which seek to raise the renewable energy share to 35 percent by 2030 and 50 percent by 2040.IMT
