Which mobile networks in Portugal performed optimally during the power outage?
In the wake of the nationwide power outage in Portugal on April 28, 2025, the resilience of various mobile network operators was put to the test. Among the operators, MEO (Altice Portugal) emerged as the most resilient, with its network demonstrating a significant advantage over competitors such as Digi, Vodafone, and NOS.
The power grid collapse forced all mobile sites off mains power, relying solely on batteries or generators. Networks quickly began exhausting backup power, and those with less mature infrastructure or weaker power autonomy, like Digi, experienced more abrupt service loss. MEO's better battery backup deployment allowed it to maintain network availability longer, supporting critical voice, text, and data services during the blackout.
According to a study by Ookla, MEO subscribers were on average half as likely to lose service compared to NOS subscribers during the outage. The figures were even more stark when compared to Vodafone and Digi, with MEO subscribers being four times less likely to lose service compared to Vodafone subscribers and six times less likely to lose service compared to Digi subscribers.
The study did not provide specific details about the robustness and wide deployment of battery backups in MEO's network. However, it is clear that MEO's network demonstrated how robust and widely deployed battery backups can delay the impacts of power outages.
In contrast, Digi's mobile network was the most impacted during the blackout. Up to 90% of Digi's subscribers lost service for more than 24 hours due to insufficient power autonomy and backup systems. These gaps in Digi's network build in Portugal potentially reflect its less mature network compared to others.
Tens of thousands of MEO subscribers likely remained connected for calls, messages, and data throughout April 28th. The MEO mobile network was found to be the most resilient during the blackout, according to Ookla's study.
It is worth noting that the study did not compare the resilience of MEO's network to Digi's network outside of Portugal. Nevertheless, the findings in Portugal underscore the importance of robust infrastructure and adequate power redundancy in ensuring network resilience during power outages.
In summary, the key reasons for Digi's network being more severely impacted are limited network maturity and insufficient power redundancy, whereas MEO's extensive battery reserves and infrastructure robustness underpinned its superior resilience during the nationwide blackout on April 28, 2025.
Despite MEO's impressive performance during the power outage in Portugal, many Digi subscribers struggled to maintain connectivity, with up to 90% experiencing service loss for over 24 hours, largely due to the company's less mature network and insufficient power redundancy. While waiting for the power grid to be restored, MEO subscribers were more likely to stay connected, thanks to their provider's robust network infrastructure and wide deployment of efficient battery backups.
