Cuba suffered another massive blackout on Wednesday, Dec. 4—the latest in a series of devastating grid disruptions that have plagued the island in recent years. While authorities reported swift restoration—completed just after midnight on Dec. 5—the event has further underscored the growing strain on the country’s fragile energy system.
Since 2020, Cuba has endured more than 20 major blackouts, with at least six nationwide outages reported in 2024 alone, including alongside a crippling disruption caused by Hurricane Rafael in November. The widespread outages, driven by fuel supply disruptions, aging infrastructure, and U.S. sanctions, have become emblematic of Cuba’s broader struggles to modernize its energy system and meet the demands of its population.
The latest debacle began in the early hours of Wednesday, Dec. 4, at 2:08 a.m., when the 330-MW Antonio Guiteras thermoelectric plant in Matanzas province disconnected from the national electrical system due to a failure in its automated system. What followed was a swift yet complex restoration effort. Below is a chronicle of the event’s critical restoration operations.
2:08 a.m. – System failure reportedThe Antonio Guiteras thermoelectric plant disconnects from the national grid due to an automatic closure of its fuel cut-off valve. The unexpected shutdown destabilizes the system, prompting technicians to begin investigating the cause. The Ministry of Energy and Mines reports that restoration work will begin immediately.
7:32 a.m. – Micro-generation systems activatedThe Electric Company of Havana restores service to two 33kV circuits, 15 13kV circuits, and four hospital circuits in the western capital. Minister of Energy and Mines Vicente de la O Levy, “conditions are more favorable than in the last disconnection” in October, given that “compliance with the procedures [are] not affected by the hurricane.” The post adds: “Islands are already functioning, and the system is gradually being restored.”
8:06 a.m. – Vital circuits prioritizedLevy emphasizes during a press conference that hospitals and water pumping stations are prioritized. “At this moment, there is an island formed in the gas plants to guarantee the supply to the capital Havana,” he says. “In the rest of the country, an indication was given to start up the islands to provide energy to the water pumping circuits.”
8:18 a.m. – No damage to generating unitsLevy confirms the shutdown occurred due to a failure in the automated system, specifically by problems in an in the control board, which likely in turn closed a shut-off valve that supplies fuel to the boiler. He stresses, “There was no damage to the country’s thermal generating units that were online at the moment of the failure.”
8:20 a.m. – Recovery progresses fasterLevy notes this restoration effort faces fewer challenges than previous outages caused by hurricanes. “This morning we put Energás unit online, and then we were already reaching San Agustín [about 40 km west of Havana] and energizing all the substations along the way. The recovery is going relatively faster.”
8:29 a.m. – Nine hospitals in Havana regain powerThe Electric Company of Havana restores service to nine hospitals and 21 circuits.
9:04 a.m. – Distributed generation islands operationalDistributed generation islands are activated nationwide, prioritizing energy for water pumping. Multiple units are ready to start up, and officials anticipate a significant recovery of the National Electric System (SEN) by the day’s end.
9:11 a.m. – Moa engines activated in eastern CubaIn the eastern province of Holguín, engines in Moa are started to supply energy to the Felton and Renté thermoelectric plants. Unit 5 of Nuevitas in Camagüey Province also begins startup operations.
9:16 a.m. – Central regional microsystem strengthenedThe Hanabanilla hydroelectric plant in central Cuba powers engines at the Cienfuegos refinery. Plans are underway to link this system to Energás Varadero, stabilizing frequency and enabling power restoration to the Guiteras plant by evening.
9:18 a.m. – Vital centers energized in MatanzasThe Electric Company of Matanzas restores power to essential facilities, including the Faustino Pérez Hospital, the communications center, and the television antenna in La Cumbre.
9:19 a.m. – Service expands in HavanaTwelve hospitals and 35 circuits in Havana, including Guanabacoa, Boyeros, and Marianao, regain electricity.
9:25 a.m. – Villa Clara restores microsystemIn Santa Clara, Villa Clara province, central Cuba,a microsystem powered by diesel engines restores electricity to circuits 13 and 40, though technical challenges at the Hanabanilla hydroelectric plant delay further recovery.
9:38 a.m. – Limited restoration in GuantánamoIn the southeastern province of Guantánamo, electricity is restored to key facilities, including the children’s hospital, general hospital, and Baracoa Hospital.
10:30 a.m. – 220 MW restored nationwideAdjunct Director of Unión Eléctrica Omar Ramírez Mendoza reports that 220 MW of power is now available across Havana, Matanzas, and the eastern provinces.
10:37 a.m. – Investigation into Guiteras failure ongoingRubén Campos Olmo, director of the Guiteras plant, confirms the shutdown was caused by the unexpected closure of the fuel valve. “No operations were being carried out at the time, and the block was stable before the failure.”
10:40 a.m. – Matanzas micro-islands operationalMicro-islands in Matanzas, western Cuba, energize the Faustino Pérez Hospital, the city center, and the television tower.
11:50 a.m. – Felton Unit 1 prepped for startupFelton Unit 1 in Holguín, eastern Cuba, is ready to start but requires 15 MW of external power to stabilize operations.
1:00 p.m. – 428 MW restored nationwideRamírez Mendoza reports progress, with Santa Cruz Unit 3 in Mayabeque Province and thermal power barges in Havana contributing to restoration efforts.
4:00 p.m. – Guiteras startup process beginsStabilized subsystems in Havana and Cienfuegos enable the Antonio Guiteras plant in Matanzas to begin startup.
7:30 p.m. – 845 MW restored nationwideNuevitas Unit 5 and Mariel Unit 6 bolster restoration efforts, extending the grid from Artemisa in the west to Las Tunas in the east.
11:34 p.m. – National electric system restoredMinister Vicente de la O Levy announces via X (formerly Twitter) that the national electric system has been mostly restored. Felton Unit 1 is expected to synchronize within hours.
12:30 a.m. (Dec. 5)—All units synchronized
The ministry confirms that the national grid has been fully restored, including Felton Unit 1.
—Amaury Pérez Sánchez () is a chemical engineer based in Cuba with the University of Camagüey.
