Havana, Cuba.- Lazaro Guerra Hernandez, Director General of Electricity at the Ministry of Energy and Mines (MINEM), reported on Monday at a press conference on the latest partial disconnection of the National Electric System (SEN) on Sunday, which affected power from the eastern province of Las Tunas to Guantanamo.

Adverse weather conditions were the cause of a trip on the 220 kV line between Nuevitas and Las Tunas, causing the incident, which did not represent a total system outage, according to a note published by Cubadebate.

At the time of the outage, generation in the eastern region was very low. One line was already de-energized due to high voltage in the region.The storm caused the second 220 kV line to go out of service. It generated a transfer outage, separating the eastern region from the rest of the country. Restoration protocols were immediately activated.

At 1:25 a.m. By Monday, all affected provinces had power restored. Unit 6 of the Mariel thermal power plant went out of service during the event.The system is currently operating stably, Guerra Hernandez stated, although a generation capacity deficit persists, as had been previously predicted.

The specialist emphasized that the outage was temporary, did not cause permanent damage to the electrical infrastructure, and the lines are currently available and operating without problems.

When addressing the behavior of the SEN during the summer season, Guerra Hernandez explained that July and August historically represent the highest energy consumption. This is due to the effect of high temperatures and the summer season. For this reason, major maintenance is prioritized for winter.

In 2025, a specific strategy was designed to face July and August in the best possible conditions. This strategy focused on optimizing thermal generation.The majority of thermoelectric plants use domestic fuel. This constitutes a strength for the system, he stated.

He highlighted the efficiency of the Boca de Jaruco and Varadero combined cycle plants. This technology is the most efficient we have in the country.

In coordination with Company Cupet, the availability of gas for these plants was secured. The goal of generating a daily average of 8.3 Gigawatts/hour (GWh) in July and August was fullfiled.

However, Guerra Hernandez acknowledged that there were difficulties and the impacts on the electrical service continued. An average daily production of 27 GWh was planned for thermoelectric plants.

In July, only 23 GWh was achieved. The main cause was the instability of the Antonio Guiteras Thermoelectric Plant, which was out of service for ten days.

The most severe impact was due to the fuel shortage. In distributed generation, production of 9.2 GWh was planned, but only 2.8 GWh was achieved.The impact of the fuel shortage was greater than that of the thermoelectric plant, he noted.

Generation from renewable sources met expectations and achieved an average daily production of 3.2 GWh. The projected daily consumption was 62 GWh, but the resulting consumption was 63 GWh.

He also noted that the lack of liquefied natural gas (LPG) increased the use of electricity for cooking, which represents approximately 1 GWh of additional consumption per day.The average daily hours affected in July were 15 hours and 50 minutes, while in August it was 14 hours and 54 minutes.

For his part, Alfredo Lopez Valdes, general director of the Cuban Electricity Company (UNE by its Spanish acronym), also told the press conference to explain that thermoelectric plants have been in operation for more than 40 years on average.

The lack of maintenance in recent years makes it difficult to predict downtime. When you start disassembling, you begin to encounter problems you didn’t foresee, he noted.

A complex case is that of Unit 2 of the Ernesto Guevara Power Plant in Santa Cruz, where it was necessary to double the scope of the initial maintenance.

Despite the efforts, maintenance has taken longer than expected. Work was done on this every one of the 62 days in July and August, he emphasized. The situation at the Cespedes 4 plant is similar. During maintenance, a hidden defect in the tubes was detected. That was a deficiency, Lopez Valdes acknowledged.
We haven’t had the financial means to resolve 100 %of the problems, he said.

Lopez Valdes reiterated that the construction of 51 photovoltaic parks is planned for this year, representing an investment of nearly one billion dollars.

Twenty-nine of these parks have already been synchronized, contributing significantly during times of high demand, such as midday.By the end of the year, solar energy could represent more than 10% of national generation.

The installation of seven donated parks, each 5 MW, is expected to be completed in September. He emphasized that four battery storage systems have been contracted to stabilize the system. “It’s a huge investment,” he concluded.