About 90 per cent of clients were without power on Tuesday morning, according to energy distribution company Luma Energy's real-time portal.
It will likely take 24 to 48 hours to turn the lights back on, "conditions permitting," Luma said in a statement.
"While the cause of the outage is under investigation, preliminary findings point to a failure in an underground line," Luma added.
Ivan Baez, a spokesman for power generator Genera, called the grid failure a "major incident" in a local radio interview.
He said that the line believed to have failed was operated by Luma and brought down plants belonging to Genera as well as private generators.
Declaraciones (8:30 a.m.): LUMA activa operaciones de emergencia para restaurar la energía después de un apagón en todo el sistema— LUMA Puerto Rico (@lumaenergypr) LUMA ha activado su Centro de Operaciones de Emergencia y actualmente está trabajando con Genera y demás colaboradores de generación para reiniciar…December 31, 2024
Genera's website showed two plants starting up again at 9.30am in the US territory.
Puerto Rico has long dealt with chronic power outages as its infrastructure crumbles.
It was hit hard by Hurricane Maria, a category four storm, in 2017.
with AP
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