Selection criteria of optimal separation pressure of liquid dominated geothermal resources

The purpose of this paper is to define the main selection criteria of the separation pressure for geothermal binary power plants to maximize the efficiency of the system. Separation pressure is one of the main parameters that defines temperature, flow and brine/steam ratio of the geothermal resource and thus it is a key point for its proper exploitation. Considering the specific constraints of each resource, it should be optimized to ensure the maximum power production and profitability of the investment with a proper cycle design. On a typical resource for binary plants, an analysis has been performed to evaluate the effect of different separation pressures on cycle selection. Following, an analysis of performances and costs of the ORC has been performed to understand the behavior of the overall system varying the separation pressure, in order to show methodology and results useful for the cycle assessment of geothermal projects.