Monitoring of Solar Still Desalination System Using the Internet of Things Technique

Abstract

In this work, a smart solar still prototype for water desalination is designed. It consists of a basic solar still, a solar preheater and a remote monitoring system based on the Internet of Things (IoT) technique. The monitoring system is developed and integrated into the hybrid solar still in order to control its evolution online, as well the quality of the freshwater provided by checking measured parameters such as pH. Thanks to the IoT technique, parameters collected by the monitoring system (e.g., air temperatures, relative humidity, etc.) are uploaded to the cloud for online remote monitoring. The users are notified by an SMS about the status of the system (e.g., water level in the basin, water in the tank, etc.), using an GSM module. The whole system, including the preheater, water pump, valve, sensors and an electronic board, is powered by a photovoltaic module of 75 Wp. The results showed that by adding a solar preheater system, the evaporation process is accelerated and, consequently, the daily yield is improved and reaches the value of 12.165 L/m2/day. The saline concentration of the tested ground water is 3.9 g/Kg (0.39%), and, after desalination, the salinity is 0.1 g/Kg (0.01%).