Experimental study on the performance of three identical solar stills with different heating methods and external condenser fully powered by photovoltaic: energy, exergy, and economic analysis

Abstract

ABSTRACT The problem of providing drinking water become a global crisis in the near future for arid and semiregions. Small-scale solar-based desalination proposed as one the promising technologies to encounter with this problem. In this paper performance of three single-slope solar stills was examined. All systems have similar condenser but each system utilized by different heating device. Thermoelectric heating (TEH), copper heater (CH), and conventional solar water (SWH) were used for systems to examine which heating methods have higher performance various thermodynamic viewpoints. In this regard, energy, exergy, and economic analysis performed on the systems. Series of experiments conducted from 2018.06.15 to 2018.07.15. From energetic and exergetic point of view, performance of the system with CH is higher than two other systems. Daily productivity of the systems with CH, THE, SWH was reached to 7460 ml/m2, 7020 ml/m2, and 6020 ml/m2 respectively. Furthermore, economic analysis indicated that the cost of produced water for system with CH, THE, and SWH evaluated by about 0.0205$/liter, 0.0213$/liter, and 0.0184 respectively. This indicated that the system utilized by SWH is economically more attractive than two others. These results showed that the proposed systems for off-grid regions which suffer from the lack of safe drinking water are an appropriate option.