Power Outage in Sumatra, PLN: Weather Disturbance, Then Plants Shut Down

JAKARTA, KOMPAS.com - The President Director of PT PLN (Persero) Darmawan Prasodjo said that the blackout in Sumatra on Friday night (22 May 2026) was triggered by bad weather. Darmawan said they found indications that the weather disturbance affected the transmission system between Muara Bungo and Sungai Rumbai in Jambi. ‘This is an early indication; there is a 275 kV transmission line between Muara Bungo and Sungai Rumbai in Jambi whose initial indication is due to weather disturbance,’ Darmawan said at a press conference as quoted by Kompas TV, on Saturday (23 May 2026). This problem then caused a domino effect resulting in a ‘shock’ to a number of PLN power plants. Because the electricity flow was interrupted and load was lost, power plants in several areas experienced oversupply. That condition increased the electrical system and voltage in the area. ‘The plants automatically disconnected from the system, or in public terms, the plants automatically tripped,’ Darmawan said. Because of the excessive load, the power plants in those areas also disconnected from the electricity system or tripped. ‘We note that this condition proved to be domino-like so that there was a disturbance to the electrical system from Jambi, Riau, North Sumatra to Aceh. And this is a fairly widespread electrical disturbance in Sumatra,’ Darmawan said. Earlier, most of Sumatra experienced a blackout on Friday night. The grid outage was reported to have occurred since 18:44 WIB. In response to the situation, PLN deployed all its teams to restore the Sumatra electricity grid.