PLN secures coal supplies as power plant outages trigger rolling blackouts in Java

By Calvin Purba

State electricity company PT Perusahaan Listrik Negara (PLN) Persero said it has secured medium-grade coal supplies for coal-fired power plants (PLTUs) across Java.

PLN President Director Darmawan Prasodjo said shipments of medium-grade coal had begun arriving at power plants across Java and that the utility had accelerated contract signings with government-assigned coal suppliers.

"We have also accelerated the contract signing process with coal suppliers, particularly those supplying medium-grade coal that have been assigned by the government," Darmawan said during a press conference on Friday.

The power plants affected by shortages of medium-grade coal supply include Pelabuhan Ratu PLTU, Lontar PLTU, Labuan PLTU, Suralaya Units 1–8, Jawa 7 PLTU, Jawa 9 and 10 PLTU, Indramayu PLTU, Paiton Units 1 and 2, Paiton 9 PLTU, Rembang PLTU, Pacitan PLTU, and Tanjung Awar-Awar PLTU.

Minister of Energy and Mineral Resources Bahlil Lahadalia said on Monday that supplies of medium-calorific coal used by PLN are becoming increasingly scarce, posing challenges to efforts to secure fuel for the country's coal-fired power plants.

Speaking at a hearing with Commission XII of the House of Representatives, Bahlil said PLN's annual coal requirement is around 154 million metric tons. To meet that demand, the government has assigned coal miners to supply about 190 million tons under its domestic market obligation (DMO) scheme.

"Of the 190 million tons assigned, around 150 million to 160 million tons have been confirmed, while 134 million tons have already been contracted," Bahlil said.

The minister said PLN still needs to secure around 20 million tons of coal to fully meet its annual requirement.

The utility is also facing disruptions at two large power plants operated by independent power producers (IPPs), which have been forced offline due to technical problems, reducing electricity supplies to Java's power grid.

"We are also facing challenges due to technical problems at two large power plants on Java owned and operated by our partners, which have been forced to go offline from the Java electricity system," Darmawan said, without identifying the facilities.

The outages prompted PLN to implement limited rolling blackouts in parts of Java on Friday to maintain system stability.

PLN's Executive Vice President for Corporate Communications, Gregorius Adi Trianto, said the utility carried out what it described as measured load management in several areas after operational problems at generating units reduced available supply.

The temporary outages, which lasted between three and five hours depending on the location, affected areas in West Java, including Bogor, Tangerang, South Tangerang and Depok, as well as parts of Central Java and East Java, including Pati, Banjarnegara, Surabaya, Pasuruan and Sidoarjo.

Gregorius said PLN was working to restore affected generating units, optimize output from other power plants and adjust system operations to minimize the impact on customers.

Indonesia's Java-Madura-Bali (Jamali) grid is the country's largest electricity system and accounts for more than half of national installed generating capacity. According to Energy Ministry data, the grid has total installed capacity of about 44.9 gigawatts, making it the backbone of Indonesia's power supply.

The recent outages have drawn attention because the Jamali system has long been regarded as having excess generating capacity. Energy analysts said, however, that surplus installed capacity does not necessarily guarantee reliability when major generating units are unavailable or fuel supplies are disrupted.

Editing by Reiner Simanjuntak