Cuba suffered a nationwide blackout on Wednesday as Hurricane Rafael brought winds of up to 185km/h (115mph) to the Caribbean island.
The country's national energy company said strong winds had caused the shutdown of the electricity system.
At least 70,000 people were evacuated from their homes before the category three storm made landfall on Wednesday evening with warnings of storm surges, flash flooding, and mudslides.
It comes just weeks after millions were left without power for four days following a blackout caused by issues with the country's creaking energy infrastructure. The incident also coincided with Hurricane Oscar, which killed at least six people.
Rafael made landfall in the western province of Artemisa, near capital Havana, at around 16:15 local time (21:15 GMT), the US National Hurricane Center (NHC) said.
A spokesperson for the state-owned energy company, Unión Eléctrica, said engineers would have to wait for the storm to pass over the island before they could assess its impact on power plants and the grid more generally.
By 22:00, Rafael had moved on into the Gulf of Mexico and weakened to a category two hurricane, with maximum wind speeds of 169km/h.
The NHC said the storm would continue to bring heavy rains across western Cuba through Thursday and that storm surges could pose a danger to life.
Heavy rains are also expected in the Cayman Islands, while a tropical storm warning is in force in the Florida Keys.
Last month, around 10 million people in Cuba were left without power following a blackout caused by maintenance issues and a lack of fuel to run power stations.
That blackout also coincided with Hurricane Oscar, a less powerful category one storm that left a trail of destruction along the island's north-eastern coast.
The worst-affected area was the eastern province of Guantánamo, where more than 1,000 homes were damaged by heavy rains and strong winds.