Well Placement Design for Enhancing Heat Recovery from Geothermal Systems: Sensitivity Analysis using Thermo-Poro-Elastic Effects

Abstract

Geothermal energy is considered one of the most promising energy to replace oil and gas. In order to enhance this type of energy from the geothermal reservoirs, an appropriate design and evaluation tool is required to assess the stimulation treatment for improving the reservoir permeability. This paper presents an innovative approach to evaluate the well placement and designed stimulation program under thermo poroelastic coupling process using momentum, mass and energy conservation. The proposed approach is applied on a selected volume of Soultz reservoir to assess the permeability enhancement over stimulation period of more than 3 month and fluid circulation period of 14 years. In this method, the change in fracture is caused by shear slippage. The proposed stimulation model evaluates different scenarios of well placement, hydraulic fracture geometry and injection program with an objective of economic heat recovery using different fracture parameters. Results show that the thermal stress led to decreasing the produced fluid temperature across the reservoir. This is due to the fact that distributed 3-D thermal stress support in increasing the fracture opening which leads to creation of flow channeling between the injectors and producers. In addition, the result show that the presented model is capable of evaluating simulation parameters such as well placement and induced fracture geometry. This has also allowed us reducing the risk of short circulating due to excessive permeability enhancement.