A major internet disruption was reported in Cuba on Monday, coinciding with a nationwide power outage caused by the complete disconnection of the National Electric System (SEN), according to Cloudflare Radar on X.
Cloudflare's platform indicated that at 17:35 UTC, internet traffic from the island dropped "significantly," experiencing an immediate 65% decrease, which aligned with the electrical collapse confirmed by the Electric Union (UNE).
This report from Cloudflare directly linked the digital traffic plunge to the failure of Cuba's electrical grid. In its post, the platform referred to the UNE statement which acknowledged, "A total disconnection of the National Electric System has occurred."
From that point forward, Cloudflare observed a sharp decline in internet flow originating from Cuba, suggesting that the blackout had an immediate effect on the nation's connectivity.
Another Widespread Blackout in Cuba
The internet service interruption occurred during a context of a general blackout that followed a day of severe energy crisis. According to the UNE, the country had faced power service disruptions throughout the previous 24 hours due to capacity deficits, and these interruptions continued into the early hours of March 16.
The highest impact reported the day before was 1,891 megawatts at 7:20 p.m., a figure that surpassed the forecast due to higher-than-expected demand. Prior to the total SEN disconnection, the system was already operating under critical conditions.
At 6:00 a.m. on the same day, UNE reported an availability of only 1,140 megawatts against a demand of 2,347, with 1,220 megawatts affected at that time. By noon, the company projected an impact of 1,250 megawatts, indicating a system functioning far below the country's actual needs.
The official report also described a greatly deteriorated generation landscape. Among the units reported as malfunctioning were Unit 5 of CTE Mariel, Units 2 and 3 of CTE Santa Cruz, Unit 2 of CTE Felton, and Units 3 and 6 of CTE Antonio Maceo. Additionally, maintenance was ongoing on Unit 6 of CTE Mariel, Unit 5 of CTE Nuevitas, and Unit 4 of CTE Carlos Manuel de Céspedes in Cienfuegos.
UNE also noted that 492 megawatts were out of service due to thermal limitations. Despite this grim scenario, the company still anticipated the startup of Unit 4 of CTE Cienfuegos with 80 megawatts during peak hours.
With this expectation, they calculated an availability of 1,220 megawatts against a maximum estimated demand of 3,150, implying a deficit of 1,930 megawatts and a forecasted impact of 1,960 megawatts at peak consumption. In essence, the crisis was already severe before the total collapse.
Unexplained Blackout
The most striking aspect of the event is that the total SEN disconnection initially lacked a clear technical explanation. The UNE assured on Facebook that "no malfunctions were reported in any of the thermal units operating at the time of the SEN disconnection," while the Ministry of Energy and Mines stated that the causes were still under investigation.
Later, UNE reported that microsystems in several territories had started functioning again and that Energás had a generating unit in service, indicating the beginning of partial recovery. However, the report does not provide a comprehensive account of the restoration or detail how long the internet access impact lasted.
Meanwhile, the report notes that 52 new photovoltaic solar parks generated 4,262 megawatt-hours, with a maximum power delivery of 732 megawatts at midday. However, this contribution neither prevented the energy crisis from worsening nor the total system collapse, and by extension, it couldn't prevent the significant impact on digital connectivity reported by Cloudflare.
Understanding Cuba's Internet and Power Crisis
What caused the internet outage in Cuba?
The internet outage in Cuba was primarily caused by a complete disconnection of the National Electric System (SEN), leading to a massive power blackout that affected connectivity.
How did the power crisis affect Cuba's electrical grid?
The power crisis caused significant disruptions in the electrical grid, with widespread blackouts and a severe shortfall in power generation capacity, leaving the grid operating under critical conditions.
Why was there no clear explanation for the blackout?
Initially, the blackout lacked a clear technical explanation because the Electric Union (UNE) and the Ministry of Energy and Mines had not identified any specific malfunctions in the operating thermal units at the time of the disconnection.