The synergy between two state-owned enterprises (SOEs) in the energy sector, PT Pertamina (Persero) and PT PLN (Persero), in developing geothermal energy has entered a new phase. Through its affiliate, PT Pertamina Geothermal Energy Tbk (PGE) (IDX: PGEO), in consortium with PT PLN Indonesia Power (PLN IP), officially reached an electricity tariff agreement with PT PLN (Persero) for the 30-megawatt (MW) Ulubelu Bottoming Unit Geothermal Power Plant (PLTP) project.
The Ulubelu Bottoming Unit is the first binary technology-based geothermal power plant project jointly developed by PGE and PLN IP in PGE's existing Ulubelu working area. This project utilizes co-generation technology to optimize residual heat energy and is part of the Independent Power Producer (IPP) procurement process at PLN. This development also supports PGE's strategy to achieve its target of 1 gigawatt (GW) of installed capacity within the next two to three years.
Edwil Suzandi, Director of Exploration & Development at PT Pertamina Geothermal Energy Tbk, stated that this electricity tariff agreement is a significant step in the collaboration between PGE and PLN IP. This will be followed by the establishment of a joint venture, EPCC procurement, and PPA, which will be simultaneously accelerated in January 2026 to achieve the Commercial Operation Date (COD) target of 2027.
"The national energy transition needs to be consistently promoted by optimizing the use of clean and reliable energy available domestically. PGE's synergy with PLN Indonesia Power in the development of the Ulubelu Bottoming Unit is expected to become a model that can be replicated in bottoming projects in other existing PGE working areas, such as Lahendong in North Sulawesi and Lumut Balai in South Sumatra. This represents PGE's real contribution to strengthening the energy transition ecosystem and national energy security," he said.
Last August, PT Pertamina (Persero) and PT PLN (Persero) signed a Memorandum of Understanding (MoU) regarding the development of geothermal energy in 19 existing projects with a total capacity of 530 MW. This synergy was facilitated by the Anagata Nusantara Power Investment Management Agency (BPI Danantara/Danantara Indonesia).
In line with the accelerated development of these existing projects, PGE and PLN IP also entered into a Consortium Commitment Agreement for the development of the 30 MW Ulubelu Bottoming Unit Geothermal Power Plant and the 15 MW Lahendong Bottoming Unit 1 Geothermal Power Plant. These two projects are expected to increase generating capacity to a total of 45 MW through the optimal use of technology.
Overall, this collaboration opens up the potential for additional capacity development of up to 1,130 MW with an estimated investment value of US$5.4 billion. This potential stems from development in existing production areas, while also opening up opportunities in new prospective areas.
As a pioneer in geothermal energy development in Indonesia with over 40 years of experience, PGE currently manages an installed capacity of 727 MW across six operating areas. PGE is also developing several strategic projects, such as the Hululais Unit 1 & 2 Geothermal Power Plant (110 MW), as well as several co-generation projects with a total capacity of 230 MW.
