Solar desalination is a common method which uses solar energy to make drinking water. Main advantages of solar stills are fresh water production is a renewable, sustainable, and economical activity. This green policy fulfills the necessary need in clean water, decreases environmental footprint, and offers financial benefits. The shape of the absorber in solar still system is very important because an inefficient absorber lead to reduced water productivity and thermal performance. This paper reviews absorber design which comprises container made out of tubes and packed with Phase Change Material (PCM) which is made up of lauric acid. The fact that PCM is encapsulated in still improves heat transfer and shows thermal energy especially when radiation changes occur. Moreover, thermal characteristics of phase change material was improved through the utilisation of scattered aluminium oxide nanoparticles. Experiments were conducted for five consecutive sunny days under identical climatic conditions. The 0.9 wt% AI2O3 PCM achieved a maximum water temperature of 72°C and productivity of 2.65 kg/m2· h. Thermal efficiency improved up to 79%, representing a 44.2% enhancement over the conventional still. Three concentrations of aluminium oxide (0.3, 0.6 and 0.9wt%) was tested. Studies have shown that lauric acid that contains 0.9wt% aluminum oxide nanoparticles has a high thermal performance when compared to the lauric acid itself. The lauric acid/aluminium oxide nanoparticles at the concentration of 0.9wt% showed improvement in temperature thermal efficiency and water productivity by about 44.2, 57, 71.2, 74 and 79 %.
Kayathri et al. (Thu,) studied this question.