Design of an autonomous photovoltaic system for desalination of groundwater by electrodialysis

Abstract

Ultrafiltration-electrodialysis (UF-ED) systems for water desalination at different scales require electrical energy. The objective of this work is to size and select the components of an autonomous photovoltaic system (APVS) to supply energy to the UF-ED system at laboratory scale in a continuous process and to determine the percentage of salinity removal (PSR) and the specific energy consumption (SEC) at different conditions of the ED system. Two PV modules and a battery were selected. A maximum power of 150 Wp was chosen for each PV module and a capacity of 200 Ah and 12 V for the battery. A charge controller was selected with a power greater than 300 Wp and a nominal charge current greater than 18.52 A and an input voltage greater than 21.6 V. An inverter with an output power greater than 112 W was selected. The PSR and SEC were determined for different operating conditions (6 V and 25 mL/min, 12 V and 25 mL/min, 6 V and 50 mL/min, 12 V and 50 mL/min). The UF-ED system reduced the salinity of the groundwater, obtaining 64% removal at 12V and 25 mL/min in a continuous process.