Meralco PowerGen Corp. (MGEN) has put 600 megawatts (MW) of MTerra Solar into commercial operation, allowing the massive renewable energy project to begin delivering contracted capacity to Manila Electric Co. (Meralco).

The company confirmed on Thursday that the commercial operations started on 26 August under MTerra Solar’s power supply agreement (PSA) with Meralco after the National Grid Corp. of the Philippines cleared the facility to safely and reliably operate 950 MW of solar capacity and 825 MW of battery energy storage system (BESS) within the grid.

“This is a significant step toward the future of energy in the Philippines. By combining solar power with battery storage at an unprecedented scale, we’re demonstrating how renewable energy can strengthen energy security, support economic growth, and build a more resilient and sustainable power system for our country,” Meralco and MGEN chairman Manuel V. Pangilinan said.

MGEN is set to bring another 250 MW covered by the same PSA into commercial operations in the coming months, further ramping up output from MTerra Solar.

The project inaugurated its first phase in July after energizing 1,373 MW of solar capacity and 825 MW, equivalent to 3,300 megawatt-hours, of battery storage.

“MTerra Solar is no longer simply a vision or a project under construction—it is now delivering power to the Filipino people. 

Reaching commercial operations reflects the determination, discipline, and exceptional work of thousands of people who helped bring this landmark facility to life. It also demonstrates what can be achieved when the government and the private sector work together toward a shared national purpose,” MGEN president and CEO Emmanuel V. Rubio said.

MTerra Solar is a joint investment of MGEN and infrastructure investor Actis. Once completed, the project is expected to have 3,500 MWp of solar capacity paired with 4,500 MWh of battery storage.

Actis has committed $600 million to MTerra Solar, which is set to become a key part of MGEN’s growing renewable energy portfolio.