Modeling of heat extraction from variably fractured porous media in Enhanced Geothermal Systems. (May 2016) - Hadgu, Teklu
Highlights: This work is on fracture characterization to be used in modeling of heat extraction from Enhanced Geothermal Systems using doublet wells. It uses the Fracture Continuum Method, which is a geostatistical approach to estimate permeability of a fracture system. The study concentrates on the effects of fracture strike, fracture dip, well separation distance and well orientation on heat extraction. Results show that fracture strike, dip and well separation distance have significant impact on heat extraction, mainly for vertical wells. Abstract: Modeling of heat extraction in Enhanced Geothermal Systems is presented. The study builds on recent studies on the use of directional wells to improve heat transfer between doublet injection and production wells. The current study focuses on the influence of fracture orientation on production temperature in deep low permeability geothermal systems, and the effects of directional drilling and separation distance between boreholes on heat extraction. The modeling results indicate that fracture orientation with respect to the well-pair plane has significant influence on reservoir thermal drawdown. The vertical well doublet is impacted significantly more than the horizontal well doublet.