Initially, work began to restore power primarily to hospitals, reports AP. On Wednesday morning, about 24 percent of households in Havana had regained power, reports AFP.
The power outage was reportedly caused by a problem with a generator unit at a thermal power plant, according to Cuba's state-owned electricity company UNE.
The two previous power outages took more than 24 hours to resolve. A shortage of oil is said to be one of the reasons for the outages in the country's fuel-fired power plants.
The oil shortage has worsened since the US decided to cut off oil supplies to Cuba.
