Antonio Guiteras, Cuba's single largest thermoelectric unit, failed at 04:58 local time on 14 May 2026 after a boiler leak. UNE confirmed the incident in its Nota Informativa. It is the plant's ninth outage of 2026, the second in nine days following the 5 May seventh failure, and the proximate trigger for the Sistema Eléctrico Nacional's 06:09 partial disconnection across the eastern provinces.
The plant sits at Matanzas on Cuba's north-central coast, and its capacity when running anchors the SEN's eastern transmission. Plant director Román Pérez Castañeda told Granma, the state newspaper, that 180 days of comprehensive maintenance are required, but "the country's situation prevents the shutdown". Antonio Guiteras has had no capital overhaul since 2010. Each restart returns the same boiler tubes to the same temperatures and pressures that failed nine times this year already.
Grid engineers track the inter-failure interval as the diagnostic figure for thermal plant deterioration. Between the 5 May outage and the 14 May outage, the gap was nine days. Earlier in 2026, intervals between failures ran multiple weeks. Compressing intervals are what engineers watch when judging whether a plant is recoverable through patch repairs or requires the full capital window the country cannot afford to grant. Pérez Castañeda's public framing has now placed that judgement on the public record.
UNE's parallel admission, in the 13 May Granma report, that over 600 circuits are in daily protection consuming more than 800 MW of available generation, points to Antonio Guiteras carrying load it can no longer reliably carry. The Mother's Day synchronisation deadline UNE technicians committed to on 5 May was met on 10 May; four days later the plant broke again.
