The Philippines, an archipelago of more than 7,600 islands across rugged and mountainous terrain, remains one of the Association of Southeast Asian Nations’ (ASEAN) fastest-growing economies. The Department of Energy (DOE) is targeting a renewable energy share of 35 per cent by 2030 and 50 per cent by 2040, up from about 25 per cent today, while system peak demand (SPD) is projected to more than quadruple from 20 GW in 2026 to over 80 GW by 2050. This expansion is being driven by a strengthening economy, a rising population, urbanisation, increasing electrification and a growing digital economy, including data centres.

Meeting this growth and unlocking renewable resources will depend on the expansion and interconnection of the Luzon, Visayas and Mindanao grids by the National Grid Corporation of the Philippines (NGCP). The latter is the privately owned consortium that has operated, maintained and developed the Philippine transmission network since 2009 under a 25-year concession and 50-year franchise. It is jointly owned by State Grid Corporation of China (40 per cent), Synergy Grid and Development Philippines (SGP) (40 per cent) and Maharlika Investment Corporation (20 per cent), which acquired its stake from SGP in January 2025.

NGCP’s August 2026 Transmission Development Plan (TDP) 2026-50 starts from a network base of 23,379 circuit (ckt) km of transmission lines and 64,581 MVA of substation capacity across 226 substations as of December 2025. Since taking over the network in 2009, NGCP has added 44,145 MVA of substation capacity and 5,633 ckt km of new and upgraded transmission lines to the network from TransCo, marking an increase of 182 per cent and 28 per cent, respectively. The backbone and major island interconnection projects identified in the current TDP pipeline are estimated to add 6,336 km of transmission lines on top of this base.

NGCP has proposed PHP388 billion in capital expenditure for the 6th Regulatory Period (6RP) 2028-32. The plan is based on rising SPD, 14 GW of committed generation capacity (70 per cent renewable) and 119 GW of indicative capacity (92 per cent renewable). To meet this growth, NGCP and the DOE’s Smart and Green Grid Plan (SGGP) have identified 418 transmission reinforcements across Luzon, Visayas and Mindanao, including new 500 kV and 230 kV backbones, submarine cable interconnections and 430 MW of battery energy storage system (BESS). A key project is the PHP90 billion Batangas–Mindoro Interconnection and Backbone Project, which will connect Mindoro to the Luzon grid.

Regional network profiles

NGCP’s transmission network comprises the Luzon, Visayas and Mindanao grids, historically separate but progressively linked through backbone upgrades and submarine/high-voltage direct current (HVDC) interconnections.

Luzon: Generation is concentrated in the north and south, while Metro Manila accounts for nearly 60 per cent of grid demand. The 500 kV backbone moves power across the island, supported by the Bolo–Nagsaag–San Jose and Mariveles–Hermosa–San Jose lines, with the southern corridor completing the loop around the capital. The loop also connects to the 440 MW Luzon–Visayas HVDC link, which has operated since 1998.

Visayas: Five sub-grids – Leyte-Samar, Cebu, Bohol, Negros and Panay – are linked by submarine cables. Leyte’s 695 MW of geothermal capacity supports Cebu through the Leyte–Luzon HVDC link. Cebu’s 2025 peak demand was 1,254 MW. The 230 kV Cebu–Negros–Panay backbone and Mindanao–Visayas Interconnection Project (MVIP) improve regional power sharing, while the 230 kV Cebu–Bohol link adds supply reliability.

Mindanao: Mindanao has a relatively stable supply-demand balance. Peak demand reached 2,775 MW in May 2026, against a 2026 forecast of 3,038 MW. A 230 kV backbone loop supports north-south transfers, while the 450 MW MVIP HVDC link, expandable to 900 MW, enables exports to Visayas. The Zamboanga Peninsula Voltage Improvement Project (ZPVIP), which added 200 MVAr static synchronous compensators (STATCOMs), strengthened voltage support ahead of further BESS integration.

Demand and generation outlook

NGCP’s planning is based on the DOE’s February 2026 SPD forecast, which projects national peak demand to rise from 19,852 MW in 2026 to 81,151 MW by 2050, implying an average annual growth of 5.93 per cent. Luzon will remain dominant, accounting for nearly 73 per cent of demand by 2050, compared with 14 per cent for Mindanao and 13 per cent for Visayas. Mindanao has the fastest long-term growth rate at 6.07 per cent, followed by Luzon at 5.96 per cent and Visayas at 5.64 per cent.

Figure 1: Philippines’ SPD forecast by grid, 2026-50 (MW)

Sources: NGCP TDP 2026-2050; REGlobal

In terms of generation, NGCP is tracking 13,839 MW of committed capacity in the DOE’s Private Sector Initiated Power Projects (PSIPP) listing as of December 2025, 70 per cent of it renewable, alongside a 119,226 MW indicative pipeline that is 92 per cent renewable. NGCP expects capacity to remain adequate through 2031 but flags weak project completion: only 23 per cent of projects in the DOE’s June 2020 PSIPP listing had reached commercial operation by December 2025.

Figure 2: Summary of committed and indicative power plant capacities (MW) (as of December 2025)

Sources: NGCP TDP 2026-2050; REGlobal

BESS is becoming increasingly important as renewable penetration increases, alongside grid-forming inverters and STATCOMs for voltage and frequency support. NGCP has recommended 430 MW of BESS across 20 priority substations, compared with 756 MW already installed, 1,884 MW committed and 3,292 MW indicative. It is also testing grid-forming “airbag” BESS at Laoag, Gamu and Santiago in Luzon and Victoria in Visayas to ease congestion and stabilise weaker grids before transmission upgrades are completed. These operate as transmission assets rather than market participants. Since February 2026, new variable renewable energy (VRE) plants of 10 MW or more must pair at least 20 per cent of capacity with storage under DOE Circular DC2026-02-0008.

The DOE’s Green Energy Auction Program (GEAP) is adding further capacity. Four rounds since June 2022 have covered multiple renewable technologies, with the latest round, focused on renewable energy paired with storage, awarding 10,195 MW in September 2025. A fifth round targeting 3,300 MW of offshore wind (OSW) is due in Q4 2026, supporting a goal of 25 GW of new renewable capacity by 2035.

Project selection also draws on the DOE’s Competitive Renewable Energy Zones (CREZ), which have narrowed 34 candidate areas to 25 since 2018, while coordinating transmission and generation development. Projects are assessed against six factors: load growth, new generation, reliability, island interconnection, power quality and market operations. The DOE’s 2024 Certificate of Energy Projects of National Significance (CEPNS) framework is also intended to speed up permits for critical projects.

Table 1: Existing transmission infrastructure by grid, as of December 2025

Source: NGCP TDP 2026-2050

Transmission and capital investment plans

As a regulated entity, NGCP’s capital expenditure (capex) is reviewed and approved by the Energy Regulatory Commission (ERC) under EPIRA. The ERC granted provisional authority for 58 projects in 2025, while NGCP filed a PHP388 billion capex programme for the 6th Regulatory Period (2028-32) in May 2026. It covers transmission lines and substations, island interconnections, system operations, metering, operations and maintenance (O&M) and support facilities, including projects carried over from the 5th Regulatory Period, due to long development lead times.

In Luzon, priorities include strengthening supply to Metro Manila, connecting new generation in Batangas, Bataan and Zambales, extending the 500 kV backbone, completing loops around the capital and adding 230 kV substations (at Lal-lo, Pinili, Porac and Castillejos). In the Visayas, plans include new submarine links connecting key islands (Boracay, Guimaras, Bohol, Cebu, Leyte and Mactan) and eventually doubling the Luzon-Visayas HVDC capacity. In Mindanao, the 230 kV backbone linking Cagayan de Oro, Davao and General Santos supports north-south transfers, with further 230 kV, 138 kV and 69 kV extensions planned, including completion of the eastern loop.

The DOE-led Smart and Green Grid Plan (SGGP) identifies 418 transmission reinforcements – 172 in Luzon, 147 in Visayas and 99 in Mindanao – covering both robust and flexible projects linked to renewable development. It targets integration of up to 50 GW of offshore wind and 4.8 GW of nuclear capacity by 2050. NGCP’s TDP translates the SGGP into technically validated projects, strengthening the three grids and progressively integrating them into a unified national transmission network.

Table 2: SGGP Phase II transmission projects by grid

Source: NGCP TDP 2026-2050

Table 3: Transmission backbone and major island interconnection projects

Note: D/C – double circuit; CREZ – Competitive Renewable Energy Zones; HVDC – high-voltage direct current; MVIP – Mindanao–Visayas Interconnection Project; N-1 – contingency criterion requiring the grid to remain operational following the loss of one major network element; NGCP – National Grid Corporation of the Philippines; OHL – overhead line; SS – substation; TDP – Transmission Development Plan.
Source: NGCP TDP 2026-2050

Grid resilience and digitalisation

Beyond capacity expansion, NGCP’s resilience programme – aligned with DOE policy under Department Circular DC2022-06-0028 – focuses on flood control, stronger towers, asset replacement and backbone loops to maintain grid reliability during typhoons and other disruptions. In 2025, system availability was 99.53 per cent in Luzon, 99.74 per cent in Visayas and 99.77 per cent in Mindanao, with frequency and voltage compliance above 99.7 per cent across all grids.

NGCP is also advancing grid digitalisation through its Central Control and Monitoring System (CCMS) (now covering 21 stations), drone and light detection and ranging (LiDAR)-based line inspections, and online transformer monitoring. New substations and upgraded substations are adopting IEC 61850-based digital architectures, supporting NGCP’s goal of a fully digitalised substation fleet by 2050.

Conclusion

The TDP 2026-50 points to a tougher planning environment, with demand more than quadrupling and an indicative generation pipeline of over 119 GW, mostly wind and solar. NGCP also highlights the continuing gap between generation coming online and transmission being ready. Its response is to expand the 500 kV and 230 kV backbone and island interconnections, use grid-forming BESS where new lines cannot be built quickly enough, and continue digitalising the network. With the 6RP capex programme before the ERC and 418 SGGP reinforcements planned, regulatory approvals and right-of-way acquisition will be key to keeping projects on schedule through 2050.