Getting Into Numerical Modeling and Simulation to Help Mitigate Geological and Associated Financial Risks by Better Tackling Geothermal Resource Uncertainty Issues at the Earliest at Exploration or Prefeasibility Stage

Abstract

As part of the GEOTREF research project dedicated to deep geothermal energy and fractured reservoirs, a cost-effective approach, relying on innovative software tools, is proposed to carry out prefeasibility studies prior drilling based on numerical conceptual models associated with phenomenological modeling and well-layout optimization. The numerical conceptual models are intended to be 3D structural, geological and geothermal numerical models that integrate at best all understanding, interpretations and data about the geothermal reservoir. They are defined at a scale where relevant boundary conditions can be specified, including recharge, basal heat flux and heat sources. Scenarios are used to formalize the uncertainty about numerical conceptual models, whether it is related to data values or interpretations, model assumptions or simplifications, or geothermal reservoir model components. Each scenario determines a numerical conceptual model as a possible representation of the actual geothermal reservoir. Phenomenological modeling is carried out by numerically simulating the geothermal systems corresponding to various scenarios. Results provide information to determine and understand the structural, geological and geothermal conditions that should be met to explain the presence of a geothermal resource. The geothermal potential of hot scenarios is then assessed by seeking optimal production and injection well locations that maximize the production of electrical power from the available geothermal energy. The application of the approach to the GEOTREF demonstration case study, located in Basse-Terre Island, the highest volcanic island of Guadeloupe, will be presented.