Thermoeconomic assessment and optimization of wells to flash–binary cycle using pure R601 and zeotropic mixtures in the Sibayak geothermal field

Abstract In this study, a flash–binary cycle is proposed with the pressure and energy loss from well to power plant are quantified in the Sibayak geothermal field. The reservoir deliverability curve is simulated using WellSim. The cycle is simulated with various zeotropic mixtures as the working fluid of the organic Rankine cycle (ORC) using Honeywell UniSim Design and optimized in terms of maximum NPV and maximum power output using Genetic Algorithm. The optimization shows that pure R601 as the ORC working fluid resulting USD 29,224,825 NPV and 27.88 MW power equivalent to 6.23 % exergy efficiency improvement compared to single flash. The integration system shows 0.73-0.93 bar pressure loss and 0.53 MW energy loss due to the consideration of pipeline system that is equal to 0.23 Cents/kWh electricity price overestimation.