THE DEVELOPMENT STUDY OF KARAHA-TALAGA BODAS GEOTHERMAL FIELD USING NUMERICAL SIMULATION

• Main Author: WELLY PRABATA - NIM : 22615303, TODHEUS
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/31347
• Institution: Institut Teknologi Bandung

<p align="justify">Karaha-Talaga Bodas geothermal field located in Garut city, West Java, Indonesia and categorized as a partially vapor-dominated geothermal field with the deep liquid reservoir underneath the steam cap. The reservoir temperature ranging from 250-350oC. The Karaha-Talaga Bodas field has two areas: Karaha in the north and Talaga in the South. The field has a thick steam cap layer in Talaga area which spreads and become thinner during flowing toward the north. The numerical simulation study is important to know the subsurface condition, calculate reserve potential and observe the change of reservoir performance with various development scenarios. This study is an integrated data analysis based on the previous study. The previous study of Karaha-Talaga Bodas Conceptual Model is a base design to build a numerical model. The TOUGH2 V.2.0 with EOS1 was used as a numerical simulation software in this study. The area of Karaha-Talaga Bodas which were modeled is 5 km x 11 km with a total thickness of 4.1 km. The natural state model of the Karaha-Talaga Bodas field has been validated using seven wells data and a conceptual model for the direction of heat and fluid flow and isothermal profile. The results show good alignment between actual data and model output data. The resources assessment was done by varying the 5 reservoir parameters then comparing the Experimental Design (ED) of Plackett-Burman (12 runs) and full factorial (32 runs). Therefore, the models have re-validated with the actual pressure and temperature, afterward, the calculation of generated power was done using well deliverability method for 30 years so the proxy equation is obtained. By the probability approach of Monte Carlo simulation, the most likely calculation result of Karaha-Talaga Bodas reserve is 120 MW. Forecasting result with four development scenarios shows that the best development is 60 MW with make-up strategy in steam zones requiring the number of production well 11, injection 3, make-up 4. The strategy produces the pressure and temperature decline of 0.2-0.6 bar/year and 2-14oC for 30 years respectively.<p align="justify"> <br /> <br />