Medco's Sarulla Geothermal Power Plant in North Sumatra Producing Below Capacity, Here's Why
The government is accelerating the recovery of the Sarulla Geothermal Power Plant (PLTP) in North Tapanuli Regency, North Sumatra, following the facility’s suboptimal production.
Despite having an installed capacity of 330 megawatts (MW), the Sarulla plant is currently unable to operate at full capacity, running at around 220 MW.
To restore the plant’s performance, the government is preparing to complete administrative processes alongside an additional investment of approximately US$270 million. This step is expected to recover Sarulla’s production whilst optimising the region’s geothermal potential, which is estimated at 1,100 MW.
Deputy Minister of Energy and Mineral Resources Yuliot said the government would first complete the necessary administrative processes by October 2026. Once that stage is finished, increased production capacity will be pursued in 2027-2028.
“First, on the administrative side, we will complete it by October 2026. Once the administrative matters are settled, we will pursue increased production capacity in 2027-2028,” Yuliot said after a meeting at the Sarulla plant in North Tapanuli Regency, North Sumatra, quoted from a written statement on Monday (3/8/2026).
According to Yuliot, restoring the plant’s capacity is expected to require additional investment of around US$270 million. The investment is aimed at returning the plant’s production capability to its installed capacity of 330 MW.
“Additional new investment of approximately US$270 million is needed to restore capacity to 330 MW, out of an available potential of 1,100 MW,” he said.
In geothermal field operations, changes in steam pressure are one of the technical challenges that must be managed continuously. This condition has caused the Sarulla plant’s current production capacity to sit at around 220 MW, against an installed capacity of 330 MW.
The government and the operator have prepared administrative settlement steps and an investment plan to restore the plant’s capacity. Once the existing capacity is back to optimal levels, further investment is planned to be carried out in stages to support utilisation of the available geothermal potential.
The Sarulla plant is located in the Pahae Julu and Pahae Jae districts of North Tapanuli Regency, North Sumatra.
The plant is operated by the Sarulla Operations Ltd. (SOL) consortium, which comprises PT Medco Power Indonesia, Ormat International, Itochu Corporation, Kyushu Electric Power Company, and Inpex Corporation.
The Sarulla plant has an installed capacity of 330 MW, divided into three units of 110 MW each. The Silangkitang unit (SIL) began commercial operation in March 2017. The Namora-I-Langit 1 unit (NIL-1) has been operating since October 2017, whilst the Namora-I-Langit 2 unit (NIL-2) began operating in May 2018.
The Sarulla plant is one of Indonesia’s strategic geothermal assets. With a resource potential of around 1,100 MW, strengthening management of the field is expected not only to restore the existing plant’s capacity, but also to support clean energy development as part of efforts to bolster national energy security.