| Title | Identifying Casing While Drilling (CWD) Potential in Geothermal Scenario Along with Economics |
|---|---|
| Authors | Dipal PATEL, Manan SHAH, Vivek THAKAR, Anirbid SIRCAR |
| Year | 2019 |
| Conference | Stanford Geothermal Workshop |
| Keywords | Geothermal Energy, Casing While Drilling, Non Productive Time, Plastering Effect, Well Control |
| Abstract | Geothermal energy is a prospective candidate for fulfilling future energy demand from renewable energy sources. The extraction of this energy mandates the drilling of a well into the formation containing high-temperature. Casing While Drilling (CWD), a method of simultaneous drilling and casing a wellbore with tubular called ‘casing’, evolves as an answer to arrest numerous drilling problems by decreasing the flat time for drilling, improving wellbore stability and integrity by ‘plastering effect’, preventing pipe stuck-up and reduced risk of well-control. In addition, it has proven to be beneficial in lowering environmental footprint with smaller rigs and enhancing rig floor safety due to lesser tubular handling. This paper discusses the working of CWD and examines the effects of certain modifications in design parameters corresponding to the geothermal environment that allows CWD to drill a geothermal production well (typically has large diameter) with negligible drilling problems. Thus, it can be counted as a remarkable techno-economic solution for drilling community in the geothermal domain. Directional drilling with level 3 CWD also extensively discussed for the high-temperature and high strength formation to achieve maximum economic benefits in geothermal project. The paper shortlisted certain challenges that need to be addressed instantly to harness maximum potential from CWD. At last, the paper provides insight into the economics of CWD that demonstrates its reliability for proved geothermal prospects. |