As of about noon local time Thursday, electricity had been restored to 120,000 of the island’s 1.4 million clients, according to Luma Energy, the private company that manages the power grid.
In a press conference, Luma’s Chief Operating Officer Wayne Stensby confirmed the blackout had started at about 8:45 p.m. Wednesday when a high-power circuit breaker near the 230 KW Costa Sur plant caught fire, causing a cascading series of generator shut-offs. But he said it would likely take “weeks” to discover the root cause of the problem.
The outage forced island officials to cancel school, shut government offices and suspend some public transportation.
While Stensby said crews were scrambling to bring power plants back online and reestablish the bulk transmission system, the company has warned that some customers might be without power until Friday.
The outage comes as some politicians have been agitating to rescind the contract with Luma, which took over grid operations from the Puerto Rico Electric Power Authority, or Prepa, in June.
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“Today, there are thousands of families suffering. No more blackouts! No more more rate hikes!” Puerto Rico House Speaker Rafael “Tatito” Hernandez wrote on Twitter, saying Prepa had been a better custodian of the grid. “Luma must go!”
Puerto Rico’s power infrastructure is notoriously old and fragile, and localized blackouts are commonplace. But Stensby said that Wednesday’s system-wide outage “was very unusual.”
Luma -- a consortium of Atco Ltd. and Quanta Services Inc. working with Innovative Emergency Management Inc. -- won the contract promising to reduce power outages and costs. It also sold itself as the best company to help administer some $10 billion in federal funds earmarked to upgrade the island’s decrepit transmission and distribution system.
Stensby said Luma was contending with a fragile and weak system that had suffered decades of neglect under Prepa.
“The outage itself does speak to the state of the electric system in Puerto Rico,” he said, “which is exactly why Luma is here and exactly why the transformation of Prepa is so very, very important.”