Indonesia’s state-owned geothermal developer Pertamina Geothermal Energy (PGE) and PLN Indonesia Power (PLN IP), a subsidiary of state utility PLN, have signed a Letter of Intent (LOI) for the purchase of electricity from geothermal bottoming power units with a combined capacity of 45 megawatts (MW), it is reported.
The LOI covers the addition of a 15 MW bottoming unit at the Lahendong geothermal power plant in North Sulawesi and a 30 MW bottoming unit at the Ulubelu geothermal power plant in Lampung, according to reports. Bottoming power generation uses residual heat (brine) that has not been fully utilized at existing geothermal plants to generate additional electricity, allowing output to be expanded without new geothermal drilling, it is reported. The specific manufacturer or supplier of the bottoming power equipment has not been disclosed.
The LOI was signed on the sidelines of the 12th Indonesia International Geothermal Convention & Exhibition (IIGCE 2026), held at the Jakarta International Convention Center (JICC), by PLN Indonesia Power Director Bernadus Sudarmanta and PGE Director Ahmad Yani, it is reported.
Indonesia is one of the world’s largest holders of geothermal resources, and bottoming technology that utilizes residual heat from existing geothermal plants is drawing attention as a means of expanding renewable power generation, it is reported.
Implications for Korea’s Industry
The Southeast Asian geothermal bottoming power market is cited as a reference point for Korean power equipment and turbine manufacturers seeking new equipment supply opportunities.
Attention is focused on when a formal power purchase agreement (PPA) will follow the LOI, and on which supplier will be selected for the bottoming equipment.