Techno-economic feasibility analysis of zeotropic mixtures and pure fluids for organic Rankine cycle systems

In this paper the techno-economic feasibility of employing zeotropic mixtures as working fluids in organic Rankine cycle power systems is assessed. For an application case based on utilization low temperature geothermal heat at 135 °C, net present value system was maximized by optimizing process variables and transfer equipment design parameters. Parametric studies detailing effect assumed electricity price employed cost estimation models were carried out. The propane, i-butane, i-pentane, R1234yf, their selected for investigation, since they have shown promising performance previous studies. results suggest that highest (43.1 M€) reached mixture R1234yf/i-butane (53.3/46.7), which 2.1 M€ higher compared to most economically feasible pure fluid R1234yf 0.252 €/kWh. sensitivity analyses benefit using robust variations price, fluid, models. comparison propane mixtures, inclusion model estimating turbine efficiency assessed a relevant influence results. also indicate R1234yf/propane, R1234yf/i-butane, R1234yf/i-pentane result lower cooling water flows thereby tower costs with R1234yf.