Developers building intermittent renewable energy plants in the Philippines with a capacity of 10MW or greater will now be required to install energy storage systems (ESS) under updated rules issued by the Department of Energy (DOE).

The DOE revised its energy storage policy on February 26, 2026, introducing a framework that sets minimum storage capacity requirements for eligible projects. Under the new regulation, renewable energy plants must integrate ESS equivalent to at least 20% of their installed generating capacity as part of project development and grid integration. The department said the requirement is aligned with system impact studies and local technical standards.

Renewable deployment in the Philippines has accelerated in recent years, driven by reforms that eased restrictions on foreign investment and streamlined permitting processes for solar projects. Among the flagship developments is the 3.5GW solar and 4.5GWh battery ESS MTerra project, which achieved initial grid synchronization and energization for its first phase in February 2026.

With the country’s renewables pipeline expanding rapidly, the DOE aims to strengthen grid infrastructure through greater integration of energy storage. The new department circular mandating ESS for large-scale projects also encourages developers to deploy systems with grid-supporting capabilities. These include, but are not limited to, grid-forming inverters capable of stabilizing voltage and frequency.

While the circular does not specify preferred storage technologies, battery energy storage systems (BESS) currently dominate global energy storage deployment.

In addition, the Philippines’ transmission network provider and distribution utilities have been instructed to incorporate energy storage into grid reinforcement strategies. The DOE directed the national transmission operator to reflect ESS considerations in its transmission development plan and to propose guidelines for grid-support functionalities. Periodic technical studies and simulations will be conducted to establish standardized requirements, taking into account international benchmarks and the Philippine Grid Code.

Philippines Energy Secretary Sharon Garin said energy storage would play a key role in strengthening the country’s power system.

“Energy storage will allow the grid to absorb more renewables while maintaining reliability,” Garin said. “This policy ensures that ESS integration becomes part of system planning and project development, supporting better outcomes for consumers.”