Evaluation of Distilled Water Quality and Production Costs from a Modified Solar Still Integrated with an Outdoor Solar Water Heater

Abstract

Solar water distillation is an effective technology for producing potable water using sustainable energy sources. However, the widespread use of this technology in industrial and domestic applications is hindered by low daily production compared to other methods. In this study, a new modification was introduced by placing a hollow cylinder inside a solar distiller and then integrating the cylindrical solar distiller with a solar heater (modified solar still). An economic analysis and study of the chemical and physical properties of the modified solar still (MSS) were carried out. The MSS produced a 296–300% increase in distillate water yield compared to a commercial solar still (CSS) on 17 July 2019, and reached 400% in other months depending on weather conditions. The costs of producing a liter of distilled water from the conventional and modified solar stills were 0.0282 and 0.0268 $/lit, respectively. Thus, the proposed solar distiller design is economically feasibile, reducing the cost of production compared to a conventional distiller and previous studies. The distillate water produced by the MSS and CSS has given the best results to all TDS, pH, and electrical conductivity tests according to local and international standards. © 2021 The Authors.