Water-renewable energy Nexus: Optimization of geothermal energypowered seawater desalination systems

PIETRASANTA, ARIANA; SERGIO MUSSATI,; AGUIRRE, PIO; MOROSUK, TATIANA; MIGUEL C MUSSATI

RENEWABLE ENERGY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2022 p. 234 - 246

0960-1481

This paper addresses the optimization of geothermal energy-powered seawater desalination systems. Anonlinear optimization mathematical model was implemented into General Algebraic Modelling System(GAMS). The model embeds many candidate configurations for optimization, which result from thecombination of the following subsystems: a single flash (SFGP) or double flash (DFGP) geothermal powerplants, a multi-effect distillation (MED) process or a reverse osmosis (RO) system for freshwater production.Also, an energy recovery turbine (ERT) is embedded. The minimization of the total annual cost ofthe process represents the objective function. The proposed model is a powerful decision-making tool forselecting the optimal configuration of the integrated process, sizes, and operating conditions to meet thedemands of electricity and freshwater desired by users. It was found that for fixed 70 MW electricitygeneration and low freshwater demands (720e2880 m3/h), the optimal configuration is SFGP/MED. Forhigh freshwater demands (4320e5040 m3/h), the optimal configuration is DFGP/MED/RO. For intermediatefreshwater demand (3600 m3/h), an optimal transition configuration is in between the twoprevious configurations, i.e., SFGP/MED/RO/ERT. It is highlighted that the model can be used to simulatefixed configurations if no degrees of freedom are available.