The Philippines has flipped the switch on the world's largest integrated solar-plus-battery project on a single site. On July 14, Meralco PowerGen (MGEN) and its partners SP New Energy and Actis inaugurated Phase 1 of the MTerra Solar facility in Gapan, Nueva Ecija, energizing 1,373 MW of solar PV capacity and 825 MW of battery storage — equivalent to 3,300 MWh — with President Ferdinand R. Marcos Jr. presiding over the ceremony.
A 3,300 MWh integrated battery is the star of Phase 1
MTerra Solar Phase 1 has now fully energized all 741 battery units and can reliably deliver clean electricity to the Luzon grid, although its maximum export capacity to that grid is still capped at 750 MW pending remaining tie-in works with the operator. Following successful completion of required grid tests, the facility is ready to fulfil its 600 MW mid-merit Power Supply Agreement with Meralco, positioning it as the lowest-cost mid-merit supply in Meralco's energy mix. As of the end of June 2026, more than 2,000 MWdc of solar panels had already been installed under Phase 1 and the project had logged over 30 million work hours without a lost-time injury.
Building toward 3,500 MWp of PV and 4,500 MWh of storage
Once fully completed, MTerra Solar will deliver 3,500 MWp of solar PV capacity paired with 4,500 MWh of battery energy storage, cementing its status as the world's largest integrated solar-and-battery facility on a single site. Actis Partner and Head of Energy Infrastructure Lucy Heintz said the project reduces the country's import dependence and gives government and industrial customers "greater visibility over future power costs," while MGEN President and CEO Emmanuel V. Rubio said MTerra shows how large renewables can deliver "cleaner power, reliable and affordable electricity for Filipinos."
Community investment and agrivoltaics research
The project has so far invested Php88.6 million in local education, livelihood, public safety and community development across Nueva Ecija and Bulacan, and has benefitted more than 973,000 individual beneficiaries. MTerra is also partnering with Central Luzon State University on an agrivoltaics research programme to evaluate how crops can be cultivated around and beneath the solar panels — a template other Southeast Asian markets are watching closely.
MTerra's inauguration comes as regional operators race to pair large solar with storage; see also Giga Storage's 2,800 MWh Belgian BESS financial close and the CATL / Alfen 5 GWh sodium-ion partnership in Europe from the same week, both of which sit alongside Electrovaya's expanded Amazon battery agreement.
Reporting based on coverage from Meralco PowerGen, CleanTechnica, The Manila Times and the Philippine Star.