Visayas power distributors survive supply lack through grid connection

MANILA, Philippines - By implementing the sharing of power between Luzon and the Visayas through a submarine cable, the National Grid Corp. of the Philippines (NGCP) was able to help electric cooperatives (ECs) and distribution utilities (DUs) deliver power to household consumers even at the height of the recent supply deficiency situation in the Visayas.

The Visayas grid went on red alert last May 19 due to generation deficiency caused by the emergency shutdown of three power plants. A total of 200 megawatts (MW) generation capacity was lost from the grid during this period.

However, grid-connected ECs and DUs did not experience rotating blackouts and outages as the situation was addressed by NGCP’s High Voltage Direct Current (HVDC) submarine cable.

The submarine cable connecting the Luzon and Visayas grids allowed power to flow to and from the two island groups. During the recent supply deficiency in the Visayas, the submarine cable brought in excess power supply from Luzon to improve the supply situation in the Visayas.

The facility was instrumental in normalizing the Visayas grid with as much as 117 MW of power flowing from Luzon to the Visayas during the evening peak of May 20.

The power flow helped the Visayas avoid rotational blackouts and manual load dropping. An interruptible load program was also implemented in some parts of the Visayas to avoid rotational blackouts.

However, parts of Panay Island still experienced power interruptions since some areas are not connected to the grid. These areas source their electricity from embedded generators. In the event these generators shut down, the distribution utility connected to them is unable to source electricity from other power plants.

NGCP president Henry Sy Jr. highlighted the benefits of connecting to the transmission grid. “Grid connection has its advantages. We can import supply from Luzon if there is supply deficiency in the Visayas. Our customers are also able to enjoy lower generation charges because grid connection makes it possible for them to get electricity from cheaper energy sources, including the Wholesale Electricity Spot Market (WESM),” he said.

“When power sharing is made possible by grid connection, power sourcing is not limited to a single supplier. Limited sourcing of electricity from only one or two generation companies leads to high generation cost because of the captive nature of the market,” he said.

“Connecting to the grid gives the customers the option to negotiate better prices from a larger pool of suppliers. In case one supplier breaks down, alternative power sources may be available from the WESM or the HVDC. We are giving customers the power of choice,” he added.