| Title | Natural state chemistry of the Ijen geothermal Field – A blind geothermal system |
|---|---|
| Authors | F. Dermawan, S. Webbison, A. Johnson, R. Libbey, L. Marini, E. Mroczek, I. Saputra, D. Utomo, R. Abiyudo, J, Murphy |
| Year | 2025 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | Ijen, Blawan-Ijen, Java, Indonesia, Natural-State, Chemistry, Blind Geothermal System, Kawah Wurung |
| Abstract | In February 2025, Ijen Unit 1 achieved Commercial Operation Date with a declared capacity of 34.5 MWnet. The Ijen geothermal project is operated by Medco Cahaya Geothermal (MCG), as part of a joint venture (JV) between Medco Power International (MPI) and Ormat Technologies (ORA). The Ijen geothermal project is located in the Blawan-Ijen concession area, and the geothermal prospect that has been explored to-date is within Kawah Wurung area. This paper will discuss the natural-state chemistry of the Ijen resource which is located within the Kendeng Caldera of the Ijen volcanic complex, situated in the eastern end of Java, Indonesia. Flow testing of wells during exploration and development drilling, plus early operational data, have been collated and analyzed. The flow testing and operational results support the existence of a two-phase, liquid dominated, >300°C resource with low total dissolved solids (TDS) (<0.3% Na-Cl fluid) and relatively low dissolved gas in the liquid phase. |