The EGS pilot project in Soultz-sous-Forets, is now operated by an industry consortium, heading for optimal reservoir management. A 3D thermo-hydraulic numerical model, based on a complex geological model of the reservoir is presented with the goal to determine input parameter for an economic analysis, comparing reservoir management based on levelized cost of energy. Over the projected life time of 30 years no major thermal breakthrough is predicted, small temperature decline affects net energy output only negligibly. The results highlight the benefits of multi-well systems, offering a larger heat exchanger surface and higher flexibility for reservoir management. (C) 2014 Elsevier Ltd. All rights reserved.