An explosion and fire at an electric substation threw much of northern Puerto Rico into darkness late Sunday in a setback for the US territory's efforts to fully restore power more than five months after Hurricane Maria started the longest blackout in US history. The island's Electric Power Authority said it was optimistic power could be restored within a day, reports the AP, but the blast illustrated the challenges of restoring a power grid that was already crumbling before the Category 4 hurricane. In many cases, power workers are repairing equipment that should have been replaced but remained online due to the power authority's yearslong financial crisis. PREPA is worth roughly $4 billion, carries $9 billion in debt and has long been criticized for political patronage and inefficiency. It also struggled with frequent blackouts, including an island-wide outage in September 2016.
It was not immediately known what caused Sunday's fire, which was quickly extinguished. Officials said the explosion knocked two other substations offline and caused a total loss of 400 megawatts worth of generation. "We are trying to restore that as quickly as possible," the company said. Heavy black smoke billowed from the substation as neighbors described seeing the sky turn orange following a loud explosion. San Juan Mayor Carmen Cruz said no injuries had been reported and that power had been restored in some areas of the city. More than 400,000 power customers remain in the dark more than five months after Hurricane Maria. Puerto Rico's governor announced last month that he plans to privatize the state-owned power company, which relies on infrastructure nearly three times older than the industry average. It would be the largest restructuring of a public entity in US history.