| Title | A Non-Productive Time Analysis from Geothermal Drilling Campaign in West Java to Improve Future Drilling Planning |
|---|---|
| Authors | A. Rachmadani, R. Kusumawardani, G.P. Rizkiani, R. Redhiza, D.C. Irwansyah, K.D. Yasa, S. Nainggolan and N.F. Rozi |
| Year | 2020 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | Geothermal, Indonesia, drilling, non-productive time, offset well analysis |
| Abstract | Drilling is one of the most cost-intensive activities in a geothermal project. The longer it takes to drill a well, the more expensive the well becomes. It is therefore important to optimize the time spent in drilling to optimize the cost of a well. The occurrence of an unplanned event that might prolong the drilling operation can be classified as Non-Productive Time (NPT), and this period will contribute to the cost overrun of the well. Understanding the major NPT happened in a drilling campaign and extracting lessons learned out of it, is hence crucial for improvement in the future drilling campaign. A drilling campaign for a vapor-dominated geothermal field in West Java, Indonesia, was carried out around 25 years ago. However, the drilling activity report and data were not documented and processed properly. Therefore, when a drilling campaign expansion is about to commence, the scattered and unprocessed drilling records make it difficult to create offset well analysis. This will cause the drilling engineering and planning are not as straight-forward, because the engineer has to sort, cleanse, and processed the data first before being able to generate analysis. This paper aims to demonstrate the offset well analysis from the drilling operation perspective. An overview of daily drilling report processing into a usable information for drilling planning is discussed. The NPT contributors incurred during first drilling campaign 25 years ago are identified and analyzed. The NPT analysis then can be used to assist the drilling planning with the final goal to improve future drilling planning process and to potentially save cost by mitigating the most possible problems to occur in the field. |