A comprehensive review of the vacuum solar still systems

Freshwater scarcity is a problem that is becoming more and more of a concern over the world, and as a result, the search for solutions has become a race against time. One of the most crucial solutions for this issue is seawater desalination. The simplest and easiest type of desalination technology is seawater desalination using a solar still system. This present study reviews the past/current status of vacuum solar still systems to pave the way for researchers to improve this technology. This paper aims to describe the design specifications and highlight the merits and demerits of various vacuum techniques used in solar stills systems upon which research has been done in the recent past. Also, a discussion on future ideas is given with some recommendations in the field of vacuum solar stills improvement to economically produce sustainable potable water. The current study concludes that lowering the operating pressure of solar still systems improves system productivity and efficiency by roughly 100% and 70%, respectively. According to the research, forced vacuums account for 52% of all vacuums, while natural vacuums account for 48%. Forced vacuum is an ideal method since it combines creating vacuum conditions and evacuating the non-condensable gases, which is not possible in a natural vacuum. The system productivity and efficiency of the forced vacuum conditions are higher by 80% and 25% than that of the natural vacuum conditions. The cost of freshwater produced per liter in natural vacuum conditions is less than that of forced vacuum conditions.

Automated summary

Freshwater scarcity is a growing global concern, and seawater desalination is a crucial solution to address this issue. This study focuses on vacuum solar still systems and reviews their current status to guide future research and improvement. The study highlights the design specifications, advantages, and disadvantages of various vacuum techniques used in solar still systems. It concludes that lowering the operating pressure can significantly improve system productivity and efficiency. Forced vacuum conditions are more effective than natural vacuum conditions, but the cost of freshwater produced in natural vacuum conditions is lower than that in forced vacuum conditions.