Investigation of the effect of the water phase in the evaporator inlet on economic performance for an Organic Rankine Cycle (ORC) based on industrial data

In this paper, exergoeconomic analysis of an Organic Rankine Cycle (ORC) is presented for a local power plant, located in the southern part of Turkey. Specific Exergy Costing Method (SPECOM) is applied using balance and auxiliary equations for the exergoeconomic analysis. The capital investment cost, operating and maintenance costs, and total investment cost of ORC steam plant are calculated as 7.43 $/h, 6.69 $/h and 14.12 $/h, respectively. The unit exergy cost and exergy cost of the electricity produced by the turbine are found as 11.05 $/GJ and 14.96 $/h, respectively. In order to show the effect of the water phase in the evaporator inlet on economic performance of the system, exergoeconomic factor of the system is calculated for four different water phases. When the evaporator inlet phase is in saturated liquid form, better exergoeconomic performance is observed for the system. The highest exergoeconomic factor is observed in the pump because of the lowest exergy destruction rate and low total investment cost, while the lowest exergoeconomic factor is observed in the evaporator due to the highest exergy destruction rate in the evaporator. Moreover, payback period assessment is calculated as 3.27 years for the ORC power plant. (C) 2016 Elsevier Ltd. All rights reserved.