Assessment of an organic Rankine cycle and a Kalina cycle for a single source of low-enthalpy geothermal heat

Abstract

This article shows the simulation results of an organic Rankine cycle (ORC) operating with the R134a working fluid and a Kalina Cycle operating with the ammonia-water mixture in order to compare the results and detect the better performing cycle. The working conditions were attained through a field visit to the town of Los Negritos, Michoacán, where it was determined that it is a superficial low-enthalpy source. To conduct the simulations, the Software Engineering Equation Solver (EESTM) was employed. In the ORC, a net electric power output of 10.97 kWe was obtained with 4.58% cycle efficiency, while with the Kalina cycle, a net power output of 5.53 kWe was obtained along with an overall efficiency of 6.61%.