The Puerto Rico Energy Bureau (PREB) has ordered LUMA Energy to complete and file, within eight weeks of the order’s notification, a technical study identifying how much temporary generation can be safely interconnected to Puerto Rico’s grid at key substations and generation sites. The study is meant to determine how to accommodate the 800 megawatts (MW) of emergency generation contemplated under the government’s grid stabilization plan.
In a resolution and order issued Tuesday, the PREB directed LUMA to determine the maximum generation that can be injected at each location, identify limiting factors, and propose site combinations supporting a net 800 MW. LUMA must evaluate Aguirre, Costa Sur, San Juan, Palo Seco and Sabana Llana, plus other sites including at least Cambalache, Yabucoa and Mayagüez, covering both existing infrastructure and grid upgrades with costs and timelines.
The PREB said the record contains no completed system impact or facility studies for any proposed location; the only systemwide evaluation was a preliminary March 2025 assessment of thermal loading, without voltage, short-circuit or stability analyses. LUMA’s resource adequacy assessment found a structural deficit of 700 to 850 MW, with peak demand near 3,234 MW in August 2026.
LUMA concluded 800 MW of firm capacity would cut projected summer loss-of-load expectation from 7.6 days to 0.1 days. LUMA must also provide an implementation schedule for power within six months of contract execution and share its simulation files. The PREB warned that noncompliance could bring administrative penalties.