PLN Retrofits Coal-Fired Plants to Utilise Low-Rank Coal
PT PLN (Persero) has begun retrofitting its steam-powered plants to enable the use of low-calorie coal. The move aims to strengthen electricity supply reliability while adapting to shifts in national coal production composition.
PLN President Director Darmawan Prasodjo said the retrofit programme commenced at the Suralaya Power Plant Units 6 and 7. As a result, the plants, which previously required medium to high-calorie coal, can now operate using lower-calorie coal.
“Suralaya PLTU 6 and 7 previously used medium to high-calorie coal, but now they can use low-rank coal with a calorie value of around 4,100 to 4,300, down from 4,600 to 4,800,” Darmawan said during a hearing with House of Representatives Commission XII.
He explained that the need for retrofitting arose because the national coal supply has changed. Production of low-calorie coal continues to increase, while output of medium to high-calorie coal is declining.
This condition had previously affected the reliability of the electricity system, particularly in Java. PLN, together with the Ministry of Energy and Mineral Resources, subsequently strengthened the supply of coal with a calorie value above 4,500 while preparing a long-term solution through plant specification adjustments.
“Production of coal with a calorie value above 4,500 is increasingly thinning, while production of low-calorie coal is growing,” he said.
The success of the retrofit at Suralaya has prompted PLN to expand the programme to other plants. The company has included the plan in its project feasibility studies, the 2026 corporate work plan and budget, and its long-term corporate plan.
The programme will be implemented at plants owned by both PLN Indonesia Power and PLN Nusantara Power. The goal is to make the plants more flexible in utilising domestically available coal without compromising electricity supply reliability.
“With the success of the retrofit at Suralaya 6 and 7, we are now conducting feasibility studies for projects across all PLN plants. We are scaling up this success across all PLN-owned plants,” Darmawan said.
PLN considers the adjustment a long-term solution to address the changing characteristics of national coal production. The company is also continuing to strengthen the electricity system through the development of new plants and various reliability improvement programmes.
The retrofit initiative is expected to prevent similar issues from arising in the future. The effort also supports national energy security by utilising the increasingly abundant domestic coal resources.