The National Grid Corp. of the Philippines (NGCP) operates as the country’s transmission provider, managing 21,137.55 circuit-kilometers of high-voltage lines and 224 substations to transport power from generators to distribution utilities.
The Visayas grid recently faced daily yellow alerts after four major power plants, totaling 591 MW in lost capacity, went offline; stability improved following the July 1 resumption of the 150-MW PEDC Unit 3.
To support rising demand, the NGCP is pursuing major infrastructure projects, including the P11-billion Cebu-Lapu-Lapu 230-kV transmission line and the P44-billion Cebu-Leyte Interconnection project, to expand network capacity and reliability.
EVERY time a light switch is turned on or an air conditioner starts running, electricity has already traveled hundreds of kilometers through one of the country’s largest infrastructure networks before reaching homes and businesses.
While consumers often associate their monthly electric bills with distribution utilities or electric cooperatives, the National Grid Corp. of the Philippines (NGCP) plays a crucial but less visible role in ensuring electricity reaches them.
NGCP describes itself as the country’s “power superhighway,” the company responsible for transmitting electricity from power plants to distribution utilities, which then deliver it to households, offices and industries.
How power flows
Established in 2008, NGCP holds a 50-year concession to operate, maintain, expand and develop the country’s transmission network. The company is regulated by the Energy Regulatory Commission (ERC), which approves its transmission projects and determines how much it can collect through transmission charges. NGCP is jointly owned by Monte Oro Grid Resources Corp., Calaca High Power Corp. and the State Grid Corp. of China, which serves as its technical partner.
Electricity begins inside power plants that use various energy sources, including coal, geothermal steam, natural gas, hydro, wind and solar. In the Visayas, some of the largest generating plants include Therma Visayas Inc. (TVI) in Toledo City, Panay Energy Development Corp. (PEDC) in Iloilo and Kepco SPC Power Corp. in Cebu.
Once electricity is generated, it passes through transformers inside the power plant to increase its voltage to as high as 230 kilovolts (kV), or even 500 kV in other parts of the country, minimizing energy losses during long-distance travel. This is where NGCP takes over, transporting electricity from generating plants to areas where it is needed through thousands of kilometers of high-voltage transmission lines, substations and submarine cables.
As of May 2025, NGCP operates 21,137.55 circuit-kilometers of transmission lines and 224 substations with a combined capacity of 62,410.9 megavolt-amperes (MVA), serving 471 transmission customers nationwide. In the Visayas alone, the company manages 6,737.89 circuit-kilometers of transmission lines, 84 substations and 11,058.7 MVA of substation capacity. This network serves 116 transmission customers in the region, including 35 distribution utilities, 15 industrial customers and 66 power generators.
Once electricity reaches an NGCP substation, the voltage is reduced before delivery to distribution utilities like Visayan Electric Company or electric cooperatives such as Cebeco 1, 2 and 3. These utilities then distribute electricity through smaller lines and neighborhood transformers, which lower the voltage further for residential consumers.
Electricity generally moves through a chain of facilities before reaching homes and businesses. It first passes through NGCP transmission lines, then to an NGCP substation. From there, the electricity goes to the distribution utility, then through a pole-mounted transformer before reaching a home or business.
Managing yellow alerts
NGCP emphasized that it does not generate electricity but serves strictly as a transmission operator, moving available supply from power plants to consumers. Company officials frequently compare the grid to a highway. If power plants produce less electricity due to maintenance or unexpected shutdowns, NGCP cannot create additional supply; its role is limited to efficiently moving available power from one region to another when transmission capacity allows.
This distinction became evident during the Visayas power situation over the past two months. From May 11 until July 1, the Visayas grid experienced almost daily yellow alerts after four of its largest generating units simultaneously went offline. The affected facilities included TVI Unit 1 (169 MW), TVI Unit 2 (169 MW), PEDC Unit 3 (150 MW) and Kepco SPC Unit 1 (103 MW), which collectively removed 591 MW from the grid.
A yellow alert is declared whenever the grid’s contingency reserve falls below the capacity of the largest operating generating unit, serving as a standby buffer in case another major power plant suddenly trips offline. According to NGCP, the situation improved after PEDC Unit 3 resumed operations on July 1, restoring 150 MW to the Visayas grid. The restoration increased dependable capacity to 3,173 MW during the day and 2,729 MW at night, allowing the region to avoid yellow alerts beginning at 2:40 p.m. that day.
Senior network operation supervisor Amado Otarra stressed that the absence of yellow alerts does not guarantee the grid is out of danger. TVI Units 1 and 2 remain under maintenance and are expected to return only around September, meaning future alerts remain possible if another major generating unit experiences an unexpected outage.
Expanding grid infrastructure
One reason the Visayas avoided more severe shortages is its connection to the rest of the country. Unlike isolated grids, the Visayas is linked to Luzon and Mindanao through submarine cables. The Mindanao-Visayas Interconnection Project allows the region to import up to 450 MW from Mindanao, while existing transmission facilities allow another 250 MW from Luzon. These imports helped cushion the impact of the 591-MW generation loss, preventing significant capacity deficits during peak demand.
To prepare for future demand, NGCP is implementing several major transmission projects in Cebu. One flagship initiative is the Cebu-Lapu-Lapu 230-kV Transmission Line Project and the Lapu-Lapu 230-kV Substation, valued at more than P11 billion. Metro Cebu and Mactan currently rely largely on aging 138-kV transmission facilities. The new 230-kV system will significantly increase transmission capacity, reduce congestion on existing lines and support continued economic growth. Construction is underway, with submarine cables being laid between Cebu and Mactan for a targeted completion in December 2027.
NGCP is also pursuing the P44-billion Cebu-Leyte Interconnection Lines 3 and 4 Project. The project will eventually increase transfer capacity between Cebu and Leyte to 2 x 600 MW, allowing more electricity to flow among Luzon, Visayas and Mindanao while accommodating future power plants in Cebu, Leyte and Samar. Stage 1 alone will add 240 MW of transfer capacity once completed.
Despite these investments, Otarra stressed that transmission alone cannot solve power shortages. The Visayas has not commissioned a new baseload power plant since TVI Unit 2 began operating in September 2019. As of May 2026, the region has more than 4,193 MW of committed power projects — mostly renewable energy developments — alongside nearly 420 MW of battery energy storage systems. NGCP noted that long-term energy security requires continuous investment in dependable baseload generation, a balanced energy mix and better coordination among power producers, regulators and local governments.
As electricity demand continues to rise, expanding the transmission network has become just as vital as building new power plants. Metro Cebu has experienced rapid economic growth over the past decade, driven by expanding residential developments, business districts, manufacturing industries and tourism establishments, particularly on Mactan Island. According to NGCP, the existing 138-kV transmission system serving Cebu, Mandaue and Lapu-Lapu is reaching its operating limits.
The planned 230-kV Cebu-Lapu-Lapu transmission line and substation will relieve this congestion by transferring part of the electrical load from the aging Mactan Gas-Insulated Switchgear to a new, higher-capacity facility. Once operational, the new system is expected to improve reliability, reduce the risk of overloading and provide enough capacity to accommodate future demand in one of the country’s fastest-growing metropolitan areas.
Beyond Cebu, NGCP is expanding the inter-island network. Michael Baylosis, transmission planning manager for Visayas System Operation, said the Cebu-Leyte Interconnection Lines 3 and 4 will significantly increase transfer capacity between Luzon and the Visayas. At present, electricity imports from Luzon are limited because the existing submarine cables between Cebu and Leyte can only accommodate about 250 MW before reaching maximum loading capacity. The new project will install additional 230-kV submarine cables and overhead transmission lines, increasing transfer capability to 2 x 600 MW upon full completion across three phases targeted for 2031, 2033 and 2035.
Baylosis noted that engineering is rarely the primary cause of project delays. Instead, timelines are often extended by right-of-way acquisition, requests for rerouting, lengthy permitting processes and regulatory approvals. NGCP cited the MVIP as an example of how government support can accelerate implementation. Spanning nearly 400 kilometers of transmission lines and submarine cables, the project was completed in about five years due to strong cooperation from both the National Government and local government agencies.
By comparison, the smaller Batangas-Mindoro Interconnection Project took more than a decade just to secure approvals, prompting NGCP to urge local government units to expedite building permits, barangay clearances and local council resolutions.
Breaking down electricity bills
Although NGCP operates the transmission network, it does not determine electricity prices. Assistant vice president and public relations head Cynthia Perez-Alabanza explained that consumers often mistakenly assume their entire payment goes to their local distribution utility when the bill is actually split among several sectors.
More than half of every electricity bill, around 51 to 55 percent, goes to power generation companies. About 20 percent goes to distribution utilities or electric cooperatives that operate the poles, transformers and lines supplying consumers. Another 20 percent consists of government-imposed charges, including taxes and the Universal Charge. Part of this amount subsidizes off-grid communities through the Universal Charge for Missionary Electrification, while another portion services debts incurred by the former National Power Corp.
Only around four percent of the total bill goes to NGCP for transmitting electricity across the high-voltage network. Alabanza said these transmission charges are strictly regulated by the ERC under a rate cap, which determines the maximum amount the company can recover annually regardless of how much electricity is transmitted.
“If ERC allows only a certain amount for the year, that’s all NGCP can collect,” Alabanza explained.
Ultimately, the company said, keeping the lights on requires every part of the electricity chain, from power generators and transmission operators to distribution utilities, regulators and local governments to work together.