Indonesia’s state electricity company PT PLN (Persero) has confirmed that a widespread blackout affecting several regions in Sumatra on Friday evening was caused by a transmission disturbance along the Muara Bungo–Sungai Rumbai line in Bungo Regency, Jambi Province.
PLN Executive Vice President for Corporate Communication and Social and Environmental Responsibility, Gregorius Adi Trianto, said the disruption occurred in a 275 kilovolt (kV) transmission line, which was impacted by severe weather conditions in the area.
He added that the affected transmission system had been successfully restored by Friday night following rapid technical response efforts from PLN teams deployed to the site.
“Based on the investigation results, there was a disturbance in the 275 kV Muara Bungo–Sungai Rumbai transmission line in Bungo Regency, Jambi Province, caused by bad weather,” Gregorius said when contacted, as quoted on Saturday.
According to PLN, the incident triggered a cascading disruption in electricity supply across multiple regions, including parts of North Sumatra and West Sumatra. The blackout reportedly began at around 18:44 Western Indonesia Time (WIB) on Friday, leaving large areas without electricity during the evening hours.
Gregorius said PLN immediately mobilized teams to restore power supply, prioritizing generation recovery and gradual system stabilization in affected areas. The utility has been working to ensure that restoration processes are carried out safely and systematically to prevent further technical issues.
“PLN is ensuring that the recovery process is conducted safely. The public can monitor electricity restoration updates through the PLN Mobile application and other official PLN communication channels,” he said.
The company emphasized that restoration efforts were carried out in stages, with engineers focusing first on stabilizing the transmission network before fully normalizing distribution to affected regions. Such procedures are standard in large-scale grid disturbances to avoid additional stress on the system.
While the transmission fault has now been resolved, PLN continues to monitor the network closely to ensure stable electricity supply across Sumatra. The company has also not ruled out further preventive measures to reduce the risk of similar disruptions in the future, particularly in areas prone to extreme weather conditions.
The 275 kV Muara Bungo–Sungai Rumbai transmission line is part of a critical infrastructure corridor that supports electricity flow between generating stations and distribution networks across the central and western parts of Sumatra. Any disruption in this segment can have a widespread impact due to the interconnected nature of the regional power grid.
PLN said that extreme weather remains one of the key challenges for transmission reliability in Indonesia, especially during periods of heavy rain, strong winds, and lightning activity, which can damage high-voltage infrastructure or trigger system instability.
In recent years, the company has increased investment in grid modernization and digital monitoring systems to improve early detection of faults and accelerate response times during emergencies. These upgrades are part of a broader effort to strengthen national energy security and reduce the frequency and duration of outages.
The Sumatra blackout also highlights ongoing challenges in balancing infrastructure resilience with rapidly growing electricity demand in Indonesia’s outer regions. As industrial activity and urban development expand across Sumatra, maintaining stable and reliable power supply has become an increasingly critical priority for the state utility.
PLN reiterated its commitment to maintaining service reliability and ensuring that affected customers receive timely restoration of electricity. The company also apologized for the inconvenience caused by the blackout and thanked the public for their patience during the recovery process.
As of the latest update, most affected areas have had their electricity supply restored, although monitoring and system adjustments are still ongoing to ensure full stabilization of the grid.
