Transmission Development in the Philippines, 2026-2050: Demand Growth, Renewable Energy Integration, and Grid Modernization

Increasing electricity demand, renewable energy expansion, and transmission reliability requirements present significant challenges to long-term power system development in the Philippines. This study examined the National Grid Corporation of the Philippines Transmission Development Plan 2026–2050, focusing on demand projections, infrastructure expansion, renewable energy integration, grid modernization, and asset management. A descriptive documentary-analysis design was employed using the plan's executive summary and Chapters 1–10 as primary data sources. Information was examined through structured document review, descriptive comparisons, and thematic analysis covering the Luzon, Visayas, and Mindanao grids. Findings indicated that national peak electricity demand was projected to increase from 19,852 MW in 2026 to 81,151 MW by 2050, requiring substantial transmission development. Major priorities included high-voltage backbone reinforcement, substation expansion, inter-island interconnections, battery energy storage systems, digital substations, and advanced monitoring technologies. The plan also identified ₱83.383 billion in projected operations and maintenance capital expenditures, including ₱53.617 billion for the Substation Reliability Program. Implementation considerations included regulatory requirements, right-of-way acquisition, project scheduling, and coordination with generation development. The study concluded that coordinated infrastructure expansion, technological modernization, and lifecycle-based asset management were central to long-term transmission planning. Prioritizing timely implementation, operational flexibility, systematic maintenance, and continued performance evaluation was recommended to support transmission reliability and renewable energy integration. However, the anticipated benefits remained dependent on project implementation and changing system conditions.