Investigation of productivity improvement of a portable solar still integrated with water-cooled thermoelectric module and silica gel desiccant

Among different solar still configurations, the integrated/hybrid solar still has led to promising results in terms of distilled water production. The present study aims to enhance the water production and energy efficiency of a conventional solar still by integrating the two approaches of condensation rate augmentation (i.e., by employing thermoelectric cooling modules) and moisture content and working hour enhancement (i.e., by employing desiccant material). For this purpose, two portable integrated systems: solar still with thermoelectric cooling (TSS) and solar still with both thermoelectric cooling and desiccant material (DTSS) were built and experimentally investigated alongside a conventional solar still (SS) as the reference/base model. Using internal heat transfer equations, the theoretical expressions for the amount of distilled water production, and energy and thermal efficiencies were obtained. The daily productivity of DTSS (2.1 L/m(2) day) and TSS (2.1 L/m(2) day) was approximately seven and four times of that of SS (0.3 L/m(2) day), respectively. The daily energy efficiency in DTSS (20.74%) was improved by 188% in comparison with the SS (7.2%). The economic effectiveness of each system was also considered. The cost of water production for one liter (CPL) in DTSS was the lowest (0.0247 $/L/m(2)) and the investment return occurs in a shorter time span than the other studied systems (1.2 years).