Pertamina Geothermal Energy (PGE), a subsidiary of Indonesia’s state-owned energy giant Pertamina, has taken a significant step forward in strengthening the country’s renewable energy portfolio by submitting crucial technical documents for the planned expansion of the Lahendong geothermal field in North Sulawesi.
The documents have been formally delivered to Indonesia’s national power utility, PT PLN, as part of the evaluation process leading up to the signing of new Power Purchase Agreements (PPAs).
The submission covers the proposed development of Lahendong Geothermal Power Plant Units 7 and 8, each with a capacity of 20 MW, alongside an additional 10 MW Binary Unit. These projects are designed to boost clean, reliable baseload power generation in a region that already relies heavily on geothermal energy for its electricity needs.
Importantly, the Lahendong expansion projects have also been listed in the Ministry of National Development Planning’s (PPN/Bappenas) 2025–2029 Blue Book. This inclusion places the projects among a select group of geothermal developments across Indonesia that are eligible for foreign funding support, underlining their strategic national importance and investment appeal.
Lahendong is currently the only operational geothermal field in North Sulawesi and has seen steady capacity growth over the years through incremental additions. At present, the field operates six units with a total installed capacity of 120 MW. The site is also home to a 500-kW Organic Rankine Cycle (ORC) pilot plant and the geothermal-powered Lao-Lao Geopark, showcasing innovation and sustainability beyond electricity generation.
As part of the next phase, PGE plans to engage in detailed technical discussions with PT PLN, covering reservoir assessments, production facility design, as well as electrical and commercial studies. These discussions will form the technical and commercial backbone for the execution stage of the expansion.
Edwil Suzandi, Director of Exploration and Development at PGEO,said, “We hope that the submission of this document will enable PLN to evaluate and purchase electricity from new and renewable energy plants, while also accelerating the next stages of development. Moving forward, PGE is committed to continuing to expand the benefits of geothermal energy so that more people can truly experience it.”
Currently supplying around 30% of North Sulawesi’s electricity, the Lahendong facility is expected to raise its contribution to between 35% and 40% once the expansion is completed, reinforcing geothermal energy’s role in Indonesia’s clean energy transition.