Towards a new framework for the systematic assessment of Indonesia’s undeveloped geothermal resources

Abstract

The National Energy General Plan (RUEN) of Indonesia targets the production of 10 GWe from geothermal by 2030 and further increases to 17.5 GWe by 2050. Robust assessments of Indonesia’s undeveloped geothermal
resources are required to help prioritize systems for development.
A new method for resource assessment has been developed by the Geothermal Institute at the University of Auckland, which leverages modern geothermal modelling tools and cloud computing. The method uses the same data that are available for traditional stored heat calculation but also includes reservoir physics, wellbore physics and realistic energy extraction scenarios to provide more accurate forecasts. This framework has been used on commercial and research projects and can be applied in less than a month using widely available computational resources.
This paper discusses the application of the method to five undeveloped geothermal systems in Indonesia. The study was undertaken in collaboration with the Geological Agency (GA) of Indonesia and the Directorate-General of New Renewable Energy and Energy Conservation (EBTKE) as a step towards establishing a new framework for the systematic assessment of Indonesia’s undeveloped geothermal resources. The resource assessment framework was applied to each of the five systems; Ciremai, Kotamobagu, Maritaing, Massepe, and Papandayan. This included the development of new digital conceptual models and numerical reservoir models for each system using geoscientific data from the Geological Agency. The resource assessment results for each field are presented in a standard format, and it is envisioned that the results and the models could be made publicly available in a database of Indonesia’s geothermal resources in the future.