PRESS RELEASE
Solok Selatan, 16 October 2025
PT Supreme Energy Muara Laboh (PT SEML), a joint venture between PT Supreme Energy Sumatera, Sumitomo Corporation, and INPEX GEOTHERMAL, LTD., has officially commenced the development phase of the Muara Laboh Geothermal Power Plant Project (GPP) Unit 2 with an additional capacity of 80 MW, marked by the First Well Drilling Ceremony held in the Liki Pinangawan Muaralaboh Geothermal Working Area (WKP), Solok Selatan Regency, West Sumatra Province. The event was attended by the Governor of West Sumatra, officials from the Provincial Government, the Regent of Solok Selatan along with the Regency Government, representatives from the Ministry of Energy and Mineral Resources (MEMR), officials from PT PLN (Persero), as well as the Commissioner, President Director, and management of PT SEML.
As part of the development of the Muara Laboh GPP Unit 2, PT SEML plans to drill 6–8 production and injection wells. The construction of Muara Laboh GPP Unit 2 is expected to be completed by the end of 2027, in line with the Amendment to the Power Purchase Agreement (PPA) with PT PLN (Persero) for the development of Units 2 and 3, which was signed on December 23, 2024. The generated electricity will be supplied to PT PLN’s Sumatra grid, contributing to the renewable energy mix and strengthening electricity supply in the region (approximately 435,000 households). The additional capacity from the Muara Laboh GPP Unit 2 is expected to reduce carbon emissions by around 460,000 tons of CO₂ per year.
In January 2025, PT SEML signed a Loan Agreement with a consortium of multiple finance institutions, consisting of Japan Bank for International Cooperation (JBIC), Asian Development Bank (ADB), Mizuho Bank, Ltd., Sumitomo Mitsui Banking Corporation (SMBC), MUFG Bank, Ltd., and the Hyakugo Bank, Ltd., with insurance coverage from Nippon Export and Investment Insurance (NEXI). The total investment for the Muara Laboh GPP Unit 2 development is approximately USD 490 million. PT SEML has appointed PT Plumpang Raya Anugerah as the drilling contractor and selected an EPC consortium comprising Sumitomo Corporation, PT Inti Karya Persada Tehnik, and PT Wasa Mitra Engineering. The main turbine and generator equipment will be supplied by Fuji Electric.
The Muara Laboh GPP Unit 2 is expected to deliver significant benefits through royalty payments and production bonuses to the local government. The construction phase will create employment opportunities for around 1,500 workers and provide business prospects for local contractors and suppliers.
The Muara Laboh GPP Unit 1 (approximately 85 MW) began commercial operation on December 16, 2019, and has continued to operate in a very good performance to supply power to PT PLN (Persero).
In addition to the Muara Laboh GPP Project, PT Supreme Energy also developed the Rantau Dedap Geothermal Power Plant with a capacity of 91.2 MW in South Sumatra, which achieved Commercial Operation Date (COD) on December 26, 2021. The Rantau Dedap project is developed by PT Supreme Energy Rantau Dedap (PT SERD), a joint venture between PT Supreme Energy Sriwijaya, Marubeni Corporation, Tohoku Electric Power Co., INPEX GEOTHERMAL, LTD., and PT Energia Prima Persada.
PT Supreme Energy Rajabasa (PT SERB), a joint venture between PT Supreme Energy, Sumitomo Corporation, and INPEX GEOTHERMAL, LTD., is also preparing for exploration activities in the Gunung Rajabasa WKP, located in South Lampung Regency, Lampung Province. Exploration will begin upon completion of the PPA extension with PT PLN (Persero).
About Supreme Energy
PT Supreme Energy was founded in 2007. The company was established by professionals with extensive experience and knowledge in the energy sector in Indonesia, including active involvement in the oil and gas industry and the development and operation of geothermal energy over the past 50 years. Supreme Energy signed PPAs in 2012 for the development of three geothermal working areas and is one of the pioneers of private geothermal power producers in Indonesia.
About Sumitomo Corporation
Sumitomo Corporation conducts business activities in a wide range of industries on a global scale, with its 9 business groups and regional organizations all over the world working closely together. Sumitomo has a successful track record of EPC business in 12 geothermal power plant projects (approximately 900 MW), which is approximately 40% of current geothermal installed capacity in Indonesia. Also, Sumitomo has been active in the private power generation business since 1990 and has entered geothermal IPP business through this Muara Laboh Geothermal Power Plant Project.
About INPEX CORPORATION
INPEX CORPORATION is Japan’s largest exploration and production (E&P) company, engaged in the development and operation of oil and gas projects worldwide. We are committed to contributing to a brighter future by delivering energy in a sustainable way. As part of this commitment, we are also engaging in lower-carbon solutions such as CCS, hydrogen and integrated power supply, while pursuing new opportunities in the evolving energy landscape. INPEX GEOTHERMAL, LTD. is a subsidiary established for the purpose of conducting geothermal business.
For more information, visit https://www.inpex.com/english/index.html.