| Title | An Updated Statistic Evaluation of Drilling Performance, Drilling Cost and Well Capacity of Geothermal Fields in Indonesia |
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| Authors | Eko HARI PURWANTO, Eko SUWARNO, Carson HAKAMA, Aulia Rizky PRATAMA and Budi HERDIYANTO |
| Year | 2020 |
| Conference | World Geothermal Congress |
| Keywords | geothermal drilling cost, well capacity |
| Abstract | Geothermal electricity price is greatly affected by essential constituent predominantly exploration and development costs. Both of exploration and development drilling costs in Indonesia are accountable for nearly up to 51% of power generation project investment. Consequently the effectiveness of resource planning which followed by successful drilling operation executions will resulted in commercial well that will provide sufficient steam supply in the duration of project lifetime. This paper presents statistical evaluation of drilling performance which is conducted by using geothermal drilling unit cost (cost/ meter) criteria. This study investigates drilling cost comparison with reference to 203 drilling activities which conducted from 2011 to 2019 using statistical method. Geothermal wells in Indonesia are mostly drilled to a depth ranges from 1200 to 2800m which represented a wide range of various reservoir depths. The results indicate that drilling cost in Indonesia range from 2000 to 3900 USD/m with mean average of 3499 USD/m which somewhat higher than other geothermal leading countries. Drilling performance exhibit learning curve gradually from exploration to operation phase. We also evaluate the effect of influencing factors which affected drilling cost in Indonesia among others are drilling depths, geological setting, operational challenges, contractual scheme and other global factors such as oil price trend. This study also offers subsurface geothermal information in Indonesia which obtained from drilling activities presented in a table that contains the maximum depth of drilling, range of reservoir depth, reservoir temperature, and well capacity. By considering information on well productivity, we estimate that drilling cost per MW well capacity distribution of productive wells in Indonesia are in the ranges of 0.4 to 1.5 MUSD per MW. |