| Title | Numerical Strategy for Uncertainty Quantification in Low Enthalpy Geothermal Projects |
|---|---|
| Authors | Sannidhi SHETTY, Denis VOSKOV, David BRUHN |
| Year | 2018 |
| Conference | Stanford Geothermal Workshop |
| Keywords | low enthalpy, geothermal doublets, cold water breakthrough |
| Abstract | One of the most important technological characteristics in low enthalpy geothermal projects is the time when cold fluid from the injection well breaks into the production well. In this study, we identified a large sensitivity of thermal breakthrough time to the position of the well doublet in a hot sedimentary aquifer with the fixed geological scenario. These variations can greatly impact the lifetime of the low enthalpy geothermal project, thereby affecting the project’s economy. Here we investigate the main factors responsible for the variation of breakthrough time by performing a sensitivity analysis of different hydraulic, thermal and numerical parameters. The geological modeling software Flumy was used to generate detailed fluvial facies distributed similarly to that observed in the West Netherlands Basin (Nieuwerkerk Formation). The models were then populated with various thermal and hydraulic properties, correlated with the facies map. Various scenarios were run in ADGPRS (Automatic-Differentiation General Purpose Research Simulator) to perform a sensitivity analysis. For given technological characteristics (distance between doublet wells, injection and production rates, drainage area etc.), a difference of approximately 50% was observed in the lifetime of the project by changing the doublet positions and keeping the same distance between the doublet pair. The major numerical and geological factors contributing to the difference in breakthrough time were identified and ranked in this study. In addition, the best simulation strategy and numerical parameters for uncertainty quantification in low enthalpy geothermal projects are suggested. |