PLN explains hours-long power outages across Sumatra region
Jakarta, CNBC Indonesia — PT PLN (Persero) has apologised and provided an explanation to the public regarding electricity disruptions affecting parts of Sumatra since 18:44 yesterday. PLN’s President Director Darmawan Prasodjo said the company immediately reported the situation to the Ministry of Energy and Mineral Resources (ESDM).
‘On behalf of PT PLN (Persero), we extend our deepest apologies to all communities across Sumatra, particularly in Jambi, West Sumatra, Riau, North Sumatra and Aceh, for the disturbances in the electricity system since yesterday evening,’ he said during a virtual press conference on Saturday, 23 May 2026.
Darmawan indicated that the ministry had directed PLN to continue taking measures to correct and improve Sumatra’s electricity system, which has been experiencing disruptions. As an initial indication, a 275 kV transmission line between Muara Bungo and Sungai Rumbai in Jambi was triggered by adverse weather, leading to a disturbance in the transmission system and causing the line to leave the Sumatra grid.
‘The impact was a shock to our power plants,’ he explained. He described that in some areas, load loss caused oversupply, the system frequency rose and voltage increased, prompting plants to trip automatically. ‘In public terms, the plants automatically shut down.’ There were also areas with a deficit because generation remained low, causing the frequency to fall and the voltage to drop, which placed a burden on plants and caused them to trip from the grid automatically.
‘And we acknowledge that this condition proved to spread in a domino effect, causing disturbances in the power system from Jambi, Riau, North Sumatra to Aceh. This was a fairly widespread electrical disturbance across Sumatra,’ he emphasised.
He acknowledged electricity is a basic need for people, both for vital facilities, households and economic activity. ‘Therefore we repeat our apology. After the incident we immediately deployed the full strength of our team.’
He added that PLN had carried out assessments of damage to main substations and the transmission system. Within around two hours, the substations and transmission network had been restored. ‘This is a very different situation from the North Sumatra, West Sumatra and Aceh disaster in which there was physical damage, with towers fallen and lines severed. Today we can say the substations and transmission system have recovered,’ he stated.
Looking ahead, he added, PLN will be able to restart the plants affected by the domino effect last night. ‘The steps are: first, restart generation; second, connect those generators to the transmission system through the substations; and third, synchronise. We recognise that the power system comprises various types of generation.’
Earlier, blackouts were recorded across several parts of Sumatra. Residents reported outages from around 19:00 on Friday, 22 May 2026. Restorations were not uniform but gradual. Some areas returned to normal by Friday night around 21:00; others only recovered in the early hours of Saturday, 23 May 2026.