Optimization of the Energy Extraction Process from Enhanced Geothermal Systems

Enhanced Geothermal Systems (EGS) have emerged as a viable solution for sustainable energy extraction from hot dry rock reservoirs. In this study, numerical simulations are employed to investigate the optimization of energy extraction from enhanced geothermal systems, focusing on the effects of fracture geometry, the number of fractures, and well spacing on overall system performance and profitability. By validating the model against previously established semi-analytical and analytical models, this research explores the importance of the mentioned parameters in determining cumulative energy production and economic outcomes across different project lifespans. The results demonstrate that increased well spacing enhances energy output by delaying thermal breakthrough and increasing the optimal injection rates. Although small fractures have limited thermal capacity, the primary influence of fracture geometry is to limit the applicable distance between the wells. Deeper wells require more pumping power, which reduces net energy gain and lowers the optimal injection rate. Multiple fractures along the well enhance energy production, particularly at higher injection rates and for smaller fractures. Economic analyses underscore the importance of operational design (including the well placement and injection rate) in maximizing profitability.