The Antonio Guiteras Thermoelectric Power Plant, the largest electricity generation unit in Cuba, has once again been disconnected from the National Electric System (NES) this Wednesday. The shutdown was caused by a leak in the boiler's economizer, an issue that has repeatedly led to recent disconnections.
Unit 1 of the power plant, located in Matanzas, ceased operations at 4:06 PM, as reported by the Electric Union (UNE) in a brief statement shared on Facebook.
"16:06 || Unit 1 of the CTE Antonio Guiteras is offline due to a leak in the economizer," the state-run entity announced, providing no specifics regarding the scale of the defect, the repair time required, or an estimated timeline for reintegration into the electric grid.
Understanding the Economizer's Frequent Failures
The economizer, often referred to as the ECO, is a crucial component of the boiler. It harnesses the heat from combustion gases to preheat the water used in steam generation.
Its role is to enhance the plant's efficiency and minimize the fuel needed for electricity production. It consists of numerous metal tubes through which water circulates at high pressure and temperature.
Leaks can occur when there are holes, cracks, or welding failures, forcing the unit to halt operations, cool down the boiler, and replace the damaged sections before resuming functionality. At the Antonio Guiteras plant, this component has emerged as a primary source of failure.
Challenges in Repairing the Economizer
According to plant management, the economizer comprises 136 elements, each with three tubes, and exhibits defects in various areas, complicating attempts to resolve the issue through isolated repairs.
The extent of the deterioration was highlighted by Rubén Campos Olmos, the UNE's general director, back in June. He explained that a comprehensive intervention would require work on over 500 tubes and entail between 1,000 and 1,200 welding seams.
Authorities have acknowledged the need for a major overhaul that would necessitate taking the plant offline for approximately 180 days. However, this comprehensive repair remains pending, while crews continue partial tube replacements, welding repairs, and hydraulic testing whenever a new leak emerges.
Recurring Economizer Issues Throughout 2026
The economizer's problems have persisted throughout the year. By late May, official reports indicated that from January 1 to May 29, the plant experienced 12 system exits due to various malfunctions, with economizer defects accounting for 293 hours of downtime.
On May 14, the plant shut down at 4:58 AM due to a boiler leak, which later led to a partial collapse of the NES. During repairs, plant director Román Pérez Castañeda confirmed the issue originated in the economizer, necessitating the replacement of two sections of two bends and four welding seams.
On May 24, a pore in the economizer caused another disconnection at 4:12 AM, requiring a four-day halt until it rejoined the NES on May 28.
On May 29, the plant once again exited the system due to another economizer leak, having been connected for less than 36 hours. UNE confirmed it was another leak in the same component.
This pattern led Campos Olmos to publicly acknowledge three failures in the same area in just two weeks, highlighting the impossibility of replacing all deteriorated tubes during brief emergency stops.
On July 3, the plant recorded its 17th exit of the year at 6:58 AM, once again due to an economizer leak. The failure occurred just four days after its previous reconnection on June 29. Repairs extended over several days due to the need to cool and inspect the boiler.
On July 26, another economizer leak took the plant offline at 1:07 AM, as reported by UNE. The repair also involved interventions in the low-temperature reheater and required several hydraulic tests. The unit successfully resynchronized on August 4.
On September 19, following a nationwide blackout the previous day, a preliminary inspection confirmed new damage to the economizer. The central's director explained that stresses during the NES disconnection might have caused or worsened perforations in various areas of the steam generator.
On September 23, while crews were attempting to complete the repair, a hydraulic test revealed another economizer leak. This issue extended the work and required repeated checks before authorization to restart. The plant returned to the system on September 27.
On October 14, yet another economizer leak resulted in a fresh shutdown, just five days after the plant had rejoined generation. The failure also caused damage to the low-temperature reheater.
During subsequent repairs, UNE announced on October 17 that crews were working on both components and replacing 11 damaged tube segments. Hydraulic and pneumatic tests were also conducted before attempting another synchronization.
Frequently Asked Questions about Antonio Guiteras Power Plant Issues
Why does the economizer frequently fail at the Antonio Guiteras plant?
The economizer at the Antonio Guiteras plant frequently fails due to the presence of holes, cracks, or welding failures in its tubes, which lead to leaks and require shutdowns for repairs.
What are the consequences of the economizer failures for the plant?
Economizer failures result in repeated shutdowns of the plant, causing disruptions in power supply and increasing downtime as repairs are carried out.
What measures are being taken to address the economizer issues?
Partial replacements of damaged tubes and welding repairs are being conducted, but a comprehensive overhaul remains necessary yet uninitiated, due to the extensive work required.