PLN Reports Progress in Restoring Electricity in Sumatra

PT PLN (Persero) is continuing to restore the electricity system in Sumatra following an outage on the 275 kilovolt (kV) Extra-High Voltage Muara Bungo–Sungai Rumbai transmission line in Jambi since Friday, 22 May. By Saturday, 23 May, 10:00 WIB, more than 8.3 million customers had regained electricity out of 13.1 million customers affected. Chief Executive Darmawan Prasodjo said that from the onset of the outage at around 18:44 WIB on Friday, PLN had immediately begun inspections and recovery of the power system. Initial indications suggested the fault was caused by severe weather, which then impacted parts of Sumatra’s electricity system. “The fault on the transmission corridor extended to a portion of Sumatra’s transmission system, causing a frequency drop due to heavy generator load and triggering a domino effect of disturbances in several regions,” he said at a press conference on Saturday, 23 May. He explained that within about two hours, the affected transmission network had been restored. After restoring the transmission, the focus was to restart the generating units previously affected and then integrate them again with the transmission system that had been prepared. “Unit start-ups are carried out systematically and in stages, prioritising system security. Hydro and gas plants can immediately assist with supply as a fast response to accelerate early recovery. By contrast, thermal plants such as coal-fired PLTU require longer, between 15 and 20 hours from start-up, synchronisation and full operation,” he noted. Restoration is being carried out concurrently from transmission, substations, to generators across Sumatra’s electricity system. To support this process, PLN has deployed hundreds of staff working 24 hours a day in affected regions from Jambi, West Sumatra, Riau, North Sumatra to Aceh. He outlined that as of 10:00 WIB on Saturday, 23 May, more than 3,192 MW of electricity supply had been restored out of a total of 5,334 MW affected. In addition, 157 substations out of 176 affected have resumed operation, bringing power supply back to 8,351,670 customers. “All staff and technical teams are now working around the clock. Recovery continues and we are all-out to restore electricity to the public as quickly as possible, in a safe manner,” Darmawan said. He added that PLN continues to coordinate with the Ministry of Energy and Mineral Resources (ESDM), local governments, relevant authorities, and all stakeholders to ensure the recovery proceeds smoothly. All efforts are focused on speeding up the restoration of the system so that power supply to the public can return to normal while maintaining system reliability. “We apologise for the inconvenience caused and we remain on standby to ensure the electricity system recovers as soon as possible so the public can resume power consumption quickly,” he concluded.