PLN's Efforts to Boost Power Plant Reliability and Prevent Blackouts

PT PLN (Persero) has detailed a series of short-term to long-term strategies to enhance the reliability of the national electricity system, primarily to prevent blackouts in the Java and Sumatra systems, which have occurred recently. PLN President Director Darmawan Prasodjo stated that in the short term, the reliability of electricity supply in Java will be strengthened through additional coal supplies with a calorific value above 4,500 kcal/kg. This additional supply is expected to increase the power plants’ dependable capacity by approximately 5 Giga Watts (GW). The company secured an additional 1.8 million tonnes of coal in July 2026, followed by an extra 3 million tonnes per month from August to December 2026, outside of existing contracts. “For Java, in the short term, this additional supply of coal with a calorific value of 4,500 and above adds 5 Giga Watts of dependable capacity on top of what already exists. And of course, we will continue to maintain and improve this as a short-term solution,” Darmawan said during a Hearing Meeting with Commission XII of the Indonesian House of Representatives on Thursday (2/7/2026). However, the company is also preparing medium- and long-term strategies, considering that the production of high-calorie coal is expected to continue declining. One such strategy is retrofitting power plants to use lower-calorie coal. According to him, a pilot retrofit project has been successfully carried out at the Suralaya Coal-Fired Power Plant. Through this modification, the plant, which previously used coal with a calorific value of around 4,600 kcal/kg, can now operate using coal with a calorific value of 4,100-4,200 kcal/kg. “And we are scaling this up across all PLN-owned power plants, in this case, both Indonesia Power and Nusantara Power,” Darmawan said. PLN is also beginning to encourage plants owned by Independent Power Producers (IPPs) to do the same, as most private power plants still rely on medium- to high-calorie coal according to their power purchase agreements. On the other hand, PLN is also accelerating the strengthening of the electricity system in Java through the construction of New and Renewable Energy power plants, in line with President Prabowo Subianto’s directive to develop 100 GW of renewable energy plants, particularly Solar Power Plants. Darmawan believes that utilising land provided by the government and reservoirs will strengthen the electricity system while reducing fuel oil consumption and the basic cost of electricity supply. “And where the potential of land provided by the government and reservoirs can be used to strengthen Java’s electricity system. We are also accelerating existing programmes in the 2025-2034 Electricity Supply Business Plan,” he said. For the Sumatra system, he acknowledged that challenges remain in the transmission network, particularly along the west coast route. Currently, the transmission network on the east coast is considered stronger than the western region. He noted that electricity supply in southern Sumatra is relatively surplus and needs to be evacuated to northern Sumatra. Therefore, PLN will strengthen the transmission network along the west coast of Sumatra. “The first is strengthening the transmission on the west coast. This is from North Sumatra to Nagan Raya, Tapaktuan, to Banda Aceh. Then also South Sumatra from Bengkulu, West Sumatra on the west coast, then to North Sumatra, Padang Sidempuan, to Aceh. With that, of course, we can carry out this strengthening,” he said. Meanwhile, in Kalimantan, the strengthening of the electricity system will be carried out through the development of new and renewable energy-based power plants, including solar, hydro, micro-hydro, wind, biomass, gas-based plants, and plans for nuclear power plant development. “Likewise with Kalimantan, there is also a part of the 100 gigawatt solar power plant that we are implementing there. Then there are gas-based plants, then renewable-based plants, be it hydro, micro-hydro, wind, solar-based, then also biomass, and also in Kalimantan there is nuclear-based,” he said.