Cuba's national electricity grid collapsed on Sunday evening, plunging the entire island — including the capital, Havana — into darkness, in what has become a recurring and worsening crisis for the Caribbean nation of roughly 11 million people. The state-run Electric Union, known by its Spanish acronym UNE, announced a "total disconnection" of the national electricity system via social media but did not initially specify the cause, the full extent of the disruption, or a timeline for restoration. As the lights went out across Havana, residents sitting outside to escape the summer heat audibly groaned. In some of the worst-affected areas, frustration has boiled over, with people setting piles of rubbish on fire or banging pots and pans in protest.

Sunday's failure is the latest in a rapid succession of nationwide blackouts. The grid collapsed three times within nine days in July alone, with one outage cutting power to the entire country. Authorities typically respond to total collapses by first creating small, isolated networks to supply hospitals, water systems and food facilities, before gradually reconnecting larger power plants. The Ministry of Energy said restoration protocols were underway, though previous recovery efforts have taken days and left the country still unable to meet basic demand even after reconnection.

The underlying causes are structural and compounding. Cuba's thermoelectric power plants are ageing — some are more than 30 years old — and have received limited maintenance due to chronic shortages of fuel and spare parts. The situation has been significantly worsened by tightening US pressure: the Trump administration has enforced an oil blockade on the island, cutting off what had been Cuba's primary fuel supply from Venezuela following Washington's designation of Venezuelan President Nicolás Maduro as a sanctions target. Oil imports from Mexico have also halted under similar pressure. Only one Russian tanker, carrying 100,000 tonnes of crude, was permitted to arrive in March; those reserves have since run out. The Trump administration has also escalated broader sanctions against Cuban state-owned businesses, prompting many foreign firms to suspend operations on the island. The Cuban government attributes the crisis squarely to Washington's policies. Critics, however, also point to decades of underinvestment and mismanagement in the energy sector.

The human toll is severe and wide-ranging. Prolonged blackouts have disrupted transport, water supplies, communications and medical services. Households have struggled to preserve food, cook meals and sleep through the intense Caribbean summer heat. For a society accustomed to hardship, the months-long energy crisis — with no clear resolution in sight — represents a deepening strain on daily life and on Cuba's already fragile economy.