Probabilistic Resource Assessment of The Ulumbu Geothermal Field, East Nusa Tenggara, Indonesia

Heru Berian Pratama (Geothermal Engineering, Master Programme, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jln. Ganesha 10, Bandung 40132,)
Iqbal Kurniawan (Geothermal Engineering, Master Programme, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jln. Ganesha 10, Bandung 40132,)
Sutopo Sutopo (Geothermal Engineering, Master Programme, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Jln. Ganesha 10, Bandung 40132,)

IJOG : Indonesian Journal on Geoscience
Vol. 9 No. 2 (2022)

DOI:10.17014/ijog.9.2.183-193A resource assessment of the Ulumbu Geothermal Field, East Nusa Tenggara, Indonesia, is proposed here. The fundamental issue of reserve estimation is determining the optimum capacity to be installed (field size) that affects the decision-making in geothermal projects. The reservoir numerical model and heat stored method are the most appropriate tools for geothermal resource assessment. Therefore, the hybrid numerical simulation and heat stored methods, coupled with the probabilistic approach, are applied to Ulumbu. Based on the calibrated numerical model, the estimation of the reservoir is divided into the steam zone and liquid reservoir. The energy reserve of the Ulumbu is estimated by Monte Carlo simulation with the results P10-P50-P90 are 71 MWe, 95 MWe, and 127 MWe, respectively