A blackout hit nearly all of Puerto Rico early on Tuesday as the U.S. territory prepared to celebrate New Year’s, leaving more than 1.3 million clients in the dark. Officials said it could take up to two days to restore power.

The outage hit at dawn, plunging the island into an eerie silence as electrical appliances and air conditioners shut down before those who could afford generators turned them on.

“It had to be on the 31st of December!” exclaimed one man, who only gave his name as Manuel, as he stood outside a grocery store in the capital of San Juan, grumbling about the outage that coincided with his birthday. “There is no happiness.”

Nearly 90% of 1.47 million clients across Puerto Rico were left in the dark, according to Luma Energy, a private company that oversees electricity transmission and distribution.

By late Tuesday night, more than 700,000 clients, including 16 hospitals and Puerto Rico's water and sewer company, had power back, according to Luma. However, the company's webpage detailing who remained without power was down.

"We understand the deep frustration this outage has caused, especially on a day like today," Luma said in a statement. “We apologize for the disruption to your plans.”

Luma said the power outage was likely caused by a failure of an underground power line. It said it's restoring power “in the quickest and safest way possible.” Hugo Sorrentini, a Luma spokesman, told The Associated Press that the incident was under investigation.

Discover Puerto Rico, a not-for-profit organization that promotes the island, warned travelers about the outage on its website and asked that cruise ship passengers contact tour operators directly to determine whether they had generators and were open for the day.

Five cruise ships were scheduled to dock in Puerto Rico on Tuesday. While most hotels were running on generators, short-term rentals lacking them reported cancellations. The main international airport in San Juan remained open.

The blackout fanned simmering anger against Luma and Genera PR, which oversees the generation of power in Puerto Rico, as a growing number of people call for their ouster.

Governor-elect Jenniffer Gonzalez Colon, who is set to be sworn in on Jan. 2, has called for the creation of an “energy czar” to review potential Luma contractual breaches while another operator is found.

“We can’t keep relying on an energy system that fails our people,” she wrote on the social media platform X, adding that stabilizing Puerto Rico’s energy grid would be her top priority in office.

Meanwhile, Gov. Pedro Pierluisi said he was in touch with Luma and Genera PR, adding on X that “we are demanding answers and solutions.”

President Joe Biden spoke with Pierluisi on Tuesday evening about the outage and offered federal assistance. Biden also spoke with U.S. Energy Secretary Jennifer Granholm and directed her to offer any help needed to speed power restoration on the island.

The outage forced businesses, parks and several malls to close, and the government announced limited schedules for some of its agencies. Workers checked on hundreds of bedridden patients and distributed ice for diabetics to keep their insulin cold.

Other Puerto Ricans began to plan ahead.

“I'll go to my balcony. That's where I'll sleep,” Raul Pacheco said with a shrug, as the 63-year-old diabetic sat on a walker nursing an injured foot.

Julio Cordova, a municipal worker, said he got dressed by the light of his cellphone and planned to buy candles.

“This affects me because I had plans. It couldn't have been yesterday or tomorrow?" he said, shaking his head as he raked leaves.

While island-wide blackouts are rare in Puerto Rico, the U.S. territory struggles with chronic power outages blamed on a crumbling power grid that was razed by Hurricane Maria, a Category 4 storm in September 2017.

The system, however, was already in decline after years of lack of maintenance and investment.

Only recently did crews start making permanent repairs to Puerto Rico’s power grid following Hurricane Maria. The island continues to depend on generators provided by the U.S. Federal Emergency Management Agency to help stabilize the grid.

In November, Puerto Rico’s government asked U.S. officials for permission to keep using more than a dozen portable generators for two additional years.

Some Puerto Ricans took the latest outage in stride.

“They're part of my everyday life,” said Enid Nunez, 49, who said she ate breakfast before work thanks to a small gas stove she bought for such events.

Meanwhile, Puerto Rico's Electric Power Authority struggles to restructure more than $9 billion in debt, the largest of the island's government agencies.

Power plants that rely on petroleum generate more than 60% of Puerto Rico's energy, followed by natural gas and coal. Solar rooftops account for only about 7% of electricity consumption on an island with a poverty rate over 40%.

Residential buildings and a hotel are seen in the dark in San Juan, Puerto Rico after a major power outage hit the island, Dec. 31, 2024. Ricardo Arduengo/AFP via Getty Images

Nearly all of Puerto Rico is without power on New Year's Eve