The US Department of Energy's Office of Energy Dominance Financing finalized a $489.4 million loan to support battery energy storage projects in Puerto Rico, according to a statement on Wednesday.
The move is expected to lower electricity costs, improve grid reliability and strengthen the island's energy security.
The financing, provided through the DOE's Office of Energy Dominance Financing, will go to Amanecer Puerto Rico, a unit of Pattern Energy.
The Department said the investment is expected to save Puerto Rican households and businesses about $312.5 million in electricity costs over the next 25 years.
The facility will fund 220 megawatts of battery energy storage systems in the municipalities of Arecibo and Santa Isabel using US-manufactured battery technology and domestic supply chains, the DOE said.
The storage systems will be capable of providing backup electricity for over 100,000 customers during power shortages and could help avoid about 13 million customer interruption hours based on 2025 operating data.
The DOE said the financing also creates a pathway for future development of natural gas-fired generation to improve the stability of Puerto Rico's electricity system and strengthen the island's long-term energy security.
Puerto Rico's electricity grid has suffered years of chronic outages and prolonged service interruptions. Its aging grid has remained vulnerable to hurricanes, earthquakes and equipment failures despite ongoing reconstruction efforts.
The department said the loan complements broader administration efforts to improve Puerto Rico's power system, including emergency orders issued since 2025 to authorize additional electricity generation, as well as support for transmission maintenance ahead of periods of peak demand and hurricane season.