Experimental analysis on single slope solar still by the inclusion of Agar-Agar (Eucheuma) Fibre and micro Phase Change Material for the productivity enhancement

The freshwater ecosystem connects humans with resources for a healthy life. One of the most typical problems confronted by living beings is the scarcity of fresh water. The clean water shortages can be alleviated by converting seawater to potable water using solar still. The limitation of solar still is its lower productivity. The main aim of this work is to enhance the productivity of single slope solar still by the inclusion of the best weight of naturally available agar-agar fibre in the absorber basin and best weight% of micro-Phase Change Material under the absorber basin. In this regard, the effect of different weights of agar-agar fibres such as 5, 10, 20, 30 and 40 g in the absorber basin was experimentally investigated. The solar still with 10 g of agar fibres in the absorber enhanced the productivity by 26.24% whereas, for 5, 20, 30 and 40 g was 16.21%, 23.14%, 21.53% and 5.15% respectively. The effect of different weight% of agar-agar powder such as 5, 10, 15 and 20 wt% in paraffin wax was investigated. The paraffin wax with 20 wt% of agar-agar powder has a better thermal conductivity of 0.34 W/mK. Furthermore, the experiment has been carried out with 10 g of agar fibre in the absorber, 20 wt% micro Phase Change Material bed under the absorber basin solar still (PCMAAF-SS) and Conventional Solar Still (CSS). From the experimentation, it was found that the overall yield of PCMAAF-SS was 4380 mL/m(2)-day on day 1 and 3950 mL/m(2)-day on day 2, for CSS it was 3030 mL/m(2)-day on day 1 and 2800 mL/m(2)-day on day 2 respectively. The thermal efficiency of PCMAAF-SS was 40% on day 1 and 36.78% on day 2 whereas the thermal efficiency of CSS was 27.68% and 26.07% on day 1 and day 2 respectively. The thermal efficiency of PCMAAF-SS was increased by 44% on day 1 and 38.08% on day 2 relative to CSS. The economic analysis revealed that the Cost per Litre and Payback period of PCMAAF-SS were $ 0.054 and 4.8 months at the same time for CSS, it was $ 0.058 and 5.1 months. From the environmental analysis, it was found that the carbon credit gained from PCMAAF-SS and CSS were $ 194.6 and $ 133.5 respectively.

Automated summary

The freshwater ecosystem is important for human well-being, but the scarcity of fresh water is a major challenge. This study explores the use of solar stills to convert seawater into potable water, with a focus on improving productivity by incorporating agar-agar fibers and micro-Phase Change Material into the absorber basin. The results show that these additions can significantly enhance the productivity and thermal efficiency of the solar still, leading to potential economic and environmental benefits.