LUMA, the company responsible for operating Puerto Rico’s electric transmission and distribution system, recently announced the arrival of the largest and highest-capacity transformer in the island’s history.
The transformer, to be installed at the Sabana Llana Transmission Center in Carolina, will directly impact over 200,000 customers and indirectly benefit more than 700,000 by reinforcing the grid and providing greater stability to prevent large-scale outages, it said.
This project, fully funded by federal resources, marks an unprecedented milestone in the modernization of Puerto Rico’s energy infrastructure, the company said. “It enhances the electric system’s resilience against large-scale cascading events, offering peace of mind to hundreds of thousands of families.”
The investment of approximately $21 million covers the purchase, design, construction, and transportation of the transformer.
It is part of the broader reconstruction of the electric system in collaboration with the Federal Emergency Management Agency (FEMA), aimed at improving grid stability for customers from Manatí to the island municipalities of Vieques and Culebra.
In June 2020, the Puerto Rico Electric Power Authority and the Puerto Rico Public-Private Partnership Authority selected LUMA Energy to operate, maintain and modernize the electricity transmission and distribution system of PREPA for fifteen years through a public-private partnership.
“This is one of the most important steps in LUMA’s ongoing efforts to stabilize Puerto Rico’s electric grid,” said Pedro Meléndez, Chief Officer of Capital Programs and Grid Transformation. He noted that since 2021, the company has launched over 500 projects to enhance grid resilience, with nearly 200 projects completed or nearing completion.
Sabana Llana, one of Puerto Rico’s most critical substations, will receive the transformer following a complex logistical transport operation from the San Juan port to the substation in Carolina.
“After months of coordination and close collaboration with the Department of Transportation and Public Works (DTOP), as well as the municipalities of San Juan and Carolina, this effort is becoming a reality. The Sabana Llana transformer is one of many that will continue arriving in the coming months. Nearly 50 modern units have begun arriving and will continue to arrive throughout 2026, nearly three years after the order was placed. This marks another key step in LUMA’s mission to improve the stability of the island’s transmission and distribution system.”
Over the past four years, LUMA has ordered more than 80 transformers, with six already installed in 2025 as part of its grid modernization plan.
Manufacturing and delivering these units is a complex process that can take between two and four years, depending on the country of origin, design specifications, required components, and technical details, LUMA noted.
This specialized logistics effort reflects the scale of commitment to Puerto Rico’s energy transformation and the need for long-term planning to ensure a more robust and reliable system, LUMA said.
Meléndez acknowledged the challenges involved in preparing for the transformer’s transport and emphasized the significant benefits it will bring once fully installed and operational at Sabana Llana in the first quarter of 2026.
“This transformer stands approximately 14 feet tall, comparable in size to a two-story house, and weighs around 250 tons, similar to the weight of a passenger airplane. It represents a significant logistical challenge. Its transport from the San Juan Port to the Sabana Llana Transmission Center will require a carefully coordinated operation led by the Department of Transportation and Public Works (DTOP),” stated Meléndez.
