First synchronization completed for Lumut Balai Unit 2 geothermal power plant, Indonesia
Lumut Balai geothermal plant, Indonesia (source: WIKA)
Carlo Cariaga
16 Jun 2025
The Lumut Balai Unit 2 geothermal power plant in Sumatra, Indonesia, has completed initial synchronization as it prepares for commercial operations.
PT Pertamina Geothermal Energy (PGEO) has announced the completion of the first synchronization of the Lumut Balai Unit 2 geothermal power plant located in South Sumatra, Indonesia. Although done at only 10% of the 55-MW facility, the synchronization process marks the first time that the facility has supplied electricity to the grid and is an important step towards full commercial operations, targeted by the end of June 2025.
The first 55-MW phase of Lumut Balai came online in 2019. Shortly after, PGEO had announced plans to expand utilization of the geothermal field with a second 55-MW unit. PGEO awarded the EPCC contract for the project in November 2022 and the groundbreaking for work on the facility took place in December 2023. Earlier this year, the PGEO Finance Director announced an April to May 2025 target for the Commercial Operations Date (COD) of Lumut Balai Unit 2.
“This synchronization is an important step where electricity from the power plant begins to be distributed to the PLN electricity network. This is also an important milestone that shows the progress of the project is on the right track,” said Ahmad Yani, Operational Director of PGEO.
A series of technical tests were completed prior to synchronization, ensuring that the power plant operates safely and efficiently. As Project Manager Achmad Sri Fadli explains, “This synchronization process is not just about connecting electricity to the PLN network, but involves rigorous system testing to ensure that the power plant operates safely, efficiently, and in accordance with applicable standards and regulations.”
PGEO has set a target increasing geothermal capacity up to 1 GW in the next two years, and ramping up to 1.7 GW by 2034. The company had set a capital expenditure budget of USD 550 million back in 2023 to support these growth initiatives.
