Performance Analysis of Floating Structures in Solar-Powered Desalination

Abstract

Solar desalination employs direct sunrays in order to evaporate water vapor and collect the condensed water, making it an effective solution to combat water scarcity. In this experimental study, a solar still with a floating absorber is placed on the water, which acts as a heat absorber and is used to stop the heat conducting to the condensed water present in the still. Stainless steel, with thickness of 0.05 mm and dimensions of 500 mm × 500 mm, is used; this is coated with a Cr-Mn-Fe oxide nanocoating, and a wooden frame is attached to the sheet in order to maintain the balance, allowing the still to float at a constant depth on the water. The experiment is conducted on three different levels of water (3 cm, 4 cm, and 5 cm) using a conventional solar still (CSS) and a modified solar still (MSS) under the same climatic circumstances. The total distillate for depths of 3 cm, 4 cm, and 5 cm are 390 mL, 385 mL, and 385 mL, respectively for the MSS; the depths were 250 mL, 220 mL, and 205 mL, respectively, for the CSS. Upon comparison, the MSS performed better than the CSS by 56% at the 3 cm depth of water, 75% at the 4 cm depth of water, and 87% at the 5 cm depth of water. It was deduced that desalinated water for the MSS was 15.6% more cost-effective than for the CSS, and it was also 81% more cost-effective than packaged drinking water in India.

Keywords

• Cr-Mn-Fe oxide
• floating absorber
• nano-coating
• solar desalination
• stainless steel