Cuba’s electricity operator warned of a severe generation shortfall for the evening of 4 November, after reporting interruptions to the national system throughout the previous day. The electricity company in Holguín also reported that a circuit had gone without power for more than a day.
Unión Eléctrica estimated that demand at the busiest time on Wednesday would reach 2,850 megawatts (MW), while available generation would be 960 MW. It forecast a generation deficit of 1,890 MW and an impact on electricity service of 1,920 MW if the conditions assumed in its forecast persisted.
Those figures were a prediction for the peak period, not a measurement of the interruption actually experienced at that time. The operator’s national assessment did not provide a timetable for individual communities or say how many people would be without power.
Supply interruptions across the system
The operator said electricity service had been affected by a shortage of generating capacity throughout Tuesday 3 November and that interruptions continued into the early hours of Wednesday. The highest reported impact on Tuesday was 1,905 MW, recorded at 7.30pm.
At 6am on Wednesday, the operator put available generation at 960 MW against demand of 2,180 MW, with 1,220 MW affected. It also estimated an impact of 1,500 MW around midday. A national shortage lasting through a day does not mean every household was without electricity for the whole of that period.
In the eastern province of Holguín, the provincial electricity company listed the Nicaro-Cabonico circuit as having been without service for 27 hours and 28 minutes in a Wednesday morning report. It recorded 22 hours and 42 minutes without supply for the Gibara 2 circuit and more than 22 hours for one circuit in Moa.
A later update continued to list Nicaro-Cabonico and Gibara 2 among affected circuits, but gave shorter interruption durations. The reports were snapshots at different times and do not establish how long power had been restored between interruptions.
In central Sancti Spíritus, the provincial electricity company also listed numerous circuits affected by a generation deficit. In a later update, it said it could not give a precise restoration time, noting that the duration of interruptions could change with demand and conditions on the national system.
Generating units out of service
The national operator said four thermal generating units were out of service because of faults: unit 5 at Mariel, unit 1 at Santa Cruz, unit 2 at Felton and unit 3 at Renté. Three more units were undergoing maintenance at Santa Cruz, Nuevitas and Renté.
It also reported 538 MW of limitations in thermal generation. The operator gave no dates in its bulletin for the return of the units listed as faulty or undergoing maintenance.
The operator reported that solar parks produced 2,341 megawatt hours of electricity on Tuesday, with a maximum output of 364 MW. The two measures are different: megawatt hours describe energy generated over a period, while megawatts describe power at a particular moment.
Cuba’s electricity system has faced longstanding pressure from ageing infrastructure and fuel shortages. Authorities said a nationwide grid collapse in September followed a failure on high-voltage transmission lines in central Cuba. That collapse occurred amid United States measures that have restricted oil shipments to the island.
The November shortage forecast does not, on its own, establish that the grid suffered another complete collapse. It does show the gap the operator expected between available generation and the power needed at peak demand.
Featured image: AI-generated illustration.
