The major process in geothermal energy stimulation is the injection and extraction of fluid through wells to generate power. One of the methods utilised in examining the long-term behaviour of such systems is modelling. In this paper, a three-dimensional (3-D) thermo-hydro-mechanical (THM) coupled model of a geothermal reservoir is developed to probe the productivity of the reservoir via the extraction well at different placement locations using a Multiphysics Finite Element (FE) application solver. Coupling between the thermo-hydro (HT) processes was achieved through convective velocity term and thermo-mechanical (MT) coupling through temperature and thermal expansion coefficient. Therefore, the parameters analysed were the total net energy rate, enthalpy and temperature using a boundary probe function and a parametric study step solver. The results showed that when the extraction well was placed nearer to the injection well, the productivity was found to be lower after only a few years of production, on the other hand, further placement of wells gives higher productivity.