HAVANA, Aug 3 (Reuters) - Cuba's national electrical grid collapsed again on Monday as authorities struggled to restore power following a nationwide blackout late Sunday, state-run media reported, marking a fresh setback in the country's deepening energy crisis.
The second collapse in less than a day underscored the fragility of Cuba's power system, which has become a potent symbol of the island's broader economic woes as fuel shortages, aging infrastructure and chronic underinvestment leave millions
vulnerable to increasingly frequent blackouts.
State television journalist Lazaro Manuel Alonso said a new disconnection of the National Electric System, or SEN, occurred on Monday afternoon despite progress made earlier in restoring service.
"A fluctuation caused the collapse," Alonso reported.
The UNE power utility later said adverse weather conditions affected the transmission network during restoration efforts, directly impacting generating units that had already returned to service.
"During the process of restoring the SEN, existing weather conditions caused disruptions to the grid, directly affecting generating units that were online," UNE said in a statement carried by state media.
By early evening, authorities reported some progress, saying four generating units at Energas Jaruco were operating and several transmission substations around Havana had been re-energized.
The latest outage comes after three nationwide grid failures over a nine-day period in July and another collapse late Sunday, shortly before 11 p.m. (0300 GMT on Monday).
Repeated blackouts have disrupted homes, businesses and public services across the Caribbean island of roughly 10 million people, adding to pressure on a government already battling shortages of food, fuel and medicine and a years-long economic downturn.
The electricity crisis has also taken on a diplomatic dimension. Cuba blames decades of U.S. sanctions and trade restrictions for limiting access to fuel, financing and spare parts needed to maintain its power system, while Washington says the outages reflect failures of the country's state-run economic model.
Cuba's thermal generating fleet, much of it decades old, has suffered recurring breakdowns as fuel shortages and maintenance problems strain the grid, making the system increasingly vulnerable to disruptions and complicating efforts to restore power after major outages.
(Reporting by Ayose Naranjo and Daina Beth Solomon; Editing by Kylie Madry and Stephen Coates)
