Experimental investigation of tubular solar still performance using a novel triple-evaporation system

Abstract

Increasing freshwater demand in addition to climatic changes draws attention to solar still especially tubular solar still due to its special geometry. It has superior condensation potential with limited evaporation space. This is due to limited evaporation area compared to the larger inner tube condensation area. In this study this fact will be utilized to escalate the tubular solar still evaporation ability with no fear about the condensation rate. Three-evaporators are designed to increase the passive tubular solar still evaporation rate for more device freshwater yield. Also, the economic analysis of the developed system is estimated. Results revealed good enhancement of the developed device performance achieving 3.51 L/m 2 day freshwater yield in winter season with 40 % thermal efficiency. Using three evaporators increased the yield by 30.5 % and the efficiency by 33.5 %. Moreover, the water cost per liter reduced by 16.1 %, achieving $0.017/L. It is worth noting that 1 m 2 area of this device can cover the essential water needs of one person. Also, the innovative multi evaporation system design can be utilized with larger scales as a future alternative in the solar water desalination market. • Novel tubular solar still design using multi evaporation system was developed. •The novel device produced 3.51 L/m 2 day in winter with 30.5 % enhancement. •The novel device efficiency was 40 % in winter with 33.5 % enhancement. •The novel device CPL ($0.017) was 16.1 % lower than single evaporator device. •CO 2 emissions of 16.3 tons/year can be reduced for personal essential water needs.