The U.S. Department of Energy (DOE) has finalized a $489.4 million loan to Amanecer Puerto Rico LLC, a subsidiary of Pattern Energy, to support battery energy storage projects aimed at improving grid reliability and lowering electricity costs across Puerto Rico.

The financing will fund the deployment of 220 MW of battery energy storage systems (BESS) in Arecibo and Santa Isabel. According to DOE, the projects are expected to help reduce electricity costs by an estimated $312.5 million over the next 25 years while strengthening grid resilience and supporting domestic manufacturing and supply chains.

Puerto Rico's electric grid has faced years of reliability challenges, including frequent outages and prolonged service interruptions that have affected residential customers, businesses and critical infrastructure. DOE said the financing package was restructured following a federal review to align with current priorities related to grid reliability, energy affordability and domestic manufacturing.

The battery storage systems are expected to provide backup power for more than 100,000 customers during electricity shortages and help avoid an estimated 13 million customer interruption hours based on 2025 operating data.

In addition to supporting energy storage, DOE said the financing establishes a framework for potential future development of dispatchable natural gas-fired generation to enhance grid stability and improve the island's long-term energy security.

The investment complements other federal efforts to improve Puerto Rico's electric system. DOE has continued to issue and renew emergency orders under Section 202(c) of the Federal Power Act to maintain electric reliability while supporting transmission maintenance and vegetation management ahead of periods of peak demand and hurricane season.

DOE said the financing is intended to accelerate private-sector investment in projects that strengthen grid reliability, modernize energy infrastructure and improve system resilience.