The cause behind the extensive power outage that affected various regions of Sumatra on Friday, May 22, has finally been brought to light. An investigation by the National Police’s Criminal Investigation Unit (Bareskrim Polri) pinpointed the disruption to the High Voltage Air Connection (SUTET) tower 175-176 in Tempino Village, Muaro Jambi Regency.
According to the Deputy Head of Bareskrim Polri, Police Inspector General Nunung Syaifuddin, field investigators discovered a severed transmission cable. This incident was primarily triggered by severe weather conditions, which caused instability in the electrical frequency and voltage, leading to a cascading trip of power plants.
“This disturbance resulted in instability of electrical frequency and voltage, which subsequently triggered a chain reaction of power plant trips, leading to a widespread blackout across several regions of Sumatra, including Aceh, North Sumatra, West Sumatra, Riau, Jambi, and parts of South Sumatra,” Nunung stated during a press conference on Monday, May 25.
He further elaborated, “The joint team from Bareskrim Polri was at the location suspected as the initial point of the disruption, specifically around the transmission tower in Tempino Village, Mestong District, Muaro Jambi Regency. A severed transmission cable was found there.” Despite the broken cable, Nunung confirmed that the physical condition of the transmission tower itself was generally good, showing no significant structural damage.
Eyewitness accounts from local residents indicated that the transmission cable snapped abruptly, likely due to the extreme weather. However, further technical and scientific analysis is still required to confirm this definitively. “This assumption is reinforced by witness testimonies we gathered from the community near the incident site, who reported hearing an explosion just before the power went out in the area around the transmission tower,” Nunung added.
He noted that several witnesses, including local community head Sabridal, Narto Wijoyo, and Eka Dedi Setyawan, who live close to the SUTET site, confirmed seeing the broken cable. “For further investigation, colleagues, the severed section of the transmission cable has been secured and is currently undergoing examination by the National Police’s Forensics Laboratory (Puslabfor Polri) for laboratory analysis to determine the precise cause of the damage,” he concluded.
No Sabotage
Nunung explicitly stated that there has been no indication of sabotage or any deliberate act found in connection with the Sumatra power outage. “The preliminary findings point towards technical factors and extreme weather conditions as the cause of the disruption to the electrical transmission system,” he affirmed.
Nunung urged the public to remain calm and not to be swayed by unverified information or misleading narratives that falsely suggest the incident was an act of sabotage.
Appearance of the Broken Cable
The severed transmission cable from SUTET tower 175-176 in Tempino Village, Muaro Jambi Regency, was showcased to the public. The cable appeared to be as thick as an adult’s wrist, with some of its copper strands visibly frayed and exposed.
Lightning Strikes Electrical System
Separately, Deputy Minister of Energy and Mineral Resources (ESDM), Yuliot Tanjung, confirmed that the Sumatra power outage was purely a result of natural factors, not intentional action. Yuliot revealed that lightning had struck the electrical system. “No, it was not intentional. It was purely due to natural conditions,” Yuliot stated at the House of Representatives on Monday, May 25.
Yuliot clarified that the power outage was triggered by a disturbance in the electrical transmission network in Merangin, Jambi. “From the Ministry of ESDM’s perspective regarding the Sumatra electricity incident, there was a problem with the transmission network; it was struck by lightning in Merangin,” he explained.
He further noted that the lightning strike significantly affected the electricity flow across Sumatra. This impact was particularly severe given that a substantial portion of North Sumatra’s electricity supply originates from the southern regions. “With that lightning strike, it impacted the stability of the entire system. At that moment, an incident occurred that led to a complete system blackout,” he added.
Yuliot detailed that the restoration process was conducted in phases, gradually bringing power plants back online one by one. This included hydropower plants (PLTA), geothermal, diesel power plants (PLTD), and gas-fired plants. Coal-fired power plants (PLTU), however, required a longer recovery period. “So, the process of restarting involved hydropower first, then geothermal, diesel, and also gas. Technically, coal-fired power plants need about 12 hours,” he elaborated.
The Ministry of ESDM also deployed a team to the field to monitor the recovery process in collaboration with PLN. “Thankfully, within the timeframe we coordinated with PLN, the system was able to recover 100 percent,” he confirmed. Yuliot added that the government has instructed PLN to conduct a thorough system evaluation to prevent similar incidents from recurring. This includes implementing grounding systems in lightning-prone areas and ensuring a more balanced distribution of electricity supply across regions. Grounding (also known as ‘arde’ or ‘pembumian’ in technical terms) is an electrical safety system that connects electrical installations to the earth to safely dissipate excess or fault currents.
Cable Theft During Blackout
Amidst the widespread power outage, Brimob (Mobile Brigade) of the North Sumatra Regional Police arrested a suspected copper cable thief, identified by his initials YP, on Jalan Mesjid, Deli Serdang Regency, North Sumatra, in the early hours of Sunday, May 24. Police Commissioner Ferry Walintukan, Head of Public Relations for the North Sumatra Regional Police, explained that the Brimob unit was patrolling crime-prone areas in Medan and its surroundings during the power cut.
During their patrol, Brimob officers discovered a man suspected of stealing copper cables embedded near the Helvetia Village office. “During the patrol, the team successfully apprehended a suspected perpetrator of copper cable theft found around the Helvetia Village Office,” Ferry stated in a written release on Monday, May 25.
The suspect was subsequently taken to the Medan Labuhan Sector Police for further legal processing. Ferry emphasized that increased night patrols during vulnerable hours are a preventative measure to ensure community safety and security are maintained amidst power outages. “Enhanced routine patrols represent the police’s presence in the community to prevent potential criminal acts,” Ferry concluded.
Summary
The extensive power outage across several regions of Sumatra on May 22 was investigated by Bareskrim Polri and the Ministry of Energy and Mineral Resources (ESDM). Bareskrim pinpointed a severed transmission cable at SUTET tower 175-176 in Tempino Village, Muaro Jambi, triggered by severe weather and resulting in electrical instability and cascading power plant trips. Separately, ESDM confirmed the incident was due to natural factors, specifically a lightning strike on the transmission network in Merangin, Jambi, which critically affected system stability. Both investigations concluded there was no indication of sabotage.
The severed cable, described as thick as an adult’s wrist with frayed copper strands, is currently undergoing laboratory analysis. Power restoration was conducted in phases, prioritizing hydropower, geothermal, diesel, and gas plants, with coal-fired plants requiring longer recovery periods. The government has instructed PLN to thoroughly evaluate the system, implement grounding in lightning-prone areas, and ensure a more balanced electricity distribution to prevent similar incidents. During the blackout, North Sumatra police also arrested a suspected copper cable thief.