Modelling geothermal and operating parameters of EGS installations in the lower triassic sedimentary formations of the central Poland area

The article presents the results of modelling geothermal conditions in the Lower Triassic sedimentary formations of the Polish Lowland area (central Poland) and an electricity production model for a prospective EGS (Enhanced Geothermal System) installation situated in that area. On the basis of comprehensive analyses, this area has been selected as optimal for EGS plants operating in sedimentary complexes in the Polish Lowland. Numerical modelling was conducted using TOUGH2 code and served to evaluate the energy performance of the prospective EGS plant operating in the area. Modelling results indicate that the energy performance of the EGS plant is strongly dependent on the volume and permeability of the artificially fractured zone and its net power is dependent on the power consumed by the circulating pumps that stimulate the flow. For the top layer of the Buntsandstein formation at a depth of ca. 5500 m and temperature of ca. 170 °C, the modelled net power of an EGS plant operating in the area ranged from 2 to 3 MW for a circulation of 200 m3/h, and at 100 m3/h it ranged from 1.3 to 1.6 MW depending on the permeability and volume of the fractured zone used for the circulation in question.