Cuba's national electricity grid collapsed late on Sunday, cutting power across an island of about 10 million people, then failed a second time on Monday while engineers were bringing it back. State utility Union Electrica declared a total disconnection of the national system. It is the sixth nationwide collapse this year.
Restoration had been slow before the second failure undid it. Accounts of how far it got differ. Al Jazeera reported about 23 per cent of Havana back on Monday morning, while other reporting put it at 14 per cent of the capital's supply. Several distribution areas outside Havana had also reconnected.
Two units at the Energas gas plant at Boca de Jaruco, in Mayabeque province east of Havana, were being reconnected when the system went down again. "Despite the progress made today, an oscillation triggered the collapse," said Lazaro Manuel Alonso, news director of Cuban state television.
The restart method is what makes each failure expensive. Engineers energise a small plant, use it to start a larger one, and stitch the regions together into microsystems before joining them. The Boca de Jaruco units were doing exactly that job. Every collapse sends the sequence back to the start.
Cuban officials attribute the failures to fuel shortages and to the condition of the thermoelectric plants, many of which have run for more than 40 years.
The fuel is the part Cuba does not control. Venezuela was its main supplier and shipments stopped in January. Mexican imports have since stopped as well, under United States pressure, according to reporting by CNN and Al Jazeera. Washington's restrictions on oil reaching the island remain in place.
The pattern predates this week. Cuba recorded at least three grid collapses in July, two of them island-wide within a single week. Counting from late 2024, this is the eleventh national failure.
Sunday's collapse came roughly a day after the system had been put back together following the previous outage. That interval is the measure of how much margin the grid has left, and officials have described the generating fleet as fragile enough to explain it.
The two constraints reinforce each other. Plants that cannot be maintained fail more often, and plants that fail more often burn through fuel that is already rationed. Neither the ageing domestic generation nor the imported input it runs on is inside Cuba's control this year.
Power was returning again on Monday afternoon, state media said, with distribution areas reconnecting one at a time. Union Electrica has not said when it expects the full system to hold.
