PLN says the Sumatra blackout was caused by bad weather

Jakarta — PT PLN (Persero) has announced a ‘blackout’ or mass power outage in Sumatra on Friday (22/5) starting at 18:44 WIB, caused by bad weather which subsequently affected part of Sumatra’s electricity system. ‘The fault on the transmission line spread to a portion of Sumatra’s transmission network, causing a frequency drop due to the heavy load on the generating plants and triggering a domino effect of disturbances in several regions,’ PLN President Director Darmawan Prasodjo said in an official statement confirmed by ANTARA from Jakarta on Saturday. From the outset of the disturbance, around 18:44 WIB on Friday (22/5), PLN immediately began inspections and restoration of the electricity system. He explained that within about two hours, the affected transmission network had been restored. After successfully restoring the transmission network, the main focus for PLN was to recommission the generators that had been affected and then align them with the transmission system that was ready. He explained that the start-up of the plants was carried out systematically and in stages, with safety of the system prioritised. Hydroelectric and gas-based plants can immediately help supply the system as a rapid response to accelerate early restoration. ‘Meanwhile, coal-fired plants such as PLTU require more time, between 15 and 20 hours from start-up, synchronisation and full operation,’ he said. Restoration was carried out simultaneously from transmission, substations, to the plants in Sumatra’s electricity system. To support the process, PLN deployed hundreds of personnel working 24 hours in the affected areas from Jambi, West Sumatra, Riau, North Sumatra, to Aceh.