Enhanced solar still performance using mix wettability surface cover and thermoelectric cooling system / Nursyahirah Mohd Shatar

Nursyahirah , Mohd Shatar (2023) Enhanced solar still performance using mix wettability surface cover and thermoelectric cooling system / Nursyahirah Mohd Shatar. PhD thesis, Universiti Malaya.

	PDF (The Candidate's Agreement) Restricted to Repository staff only Download (160Kb)
	PDF (Thesis PhD) Download (2912Kb)

Abstract

Water purification using renewable energy sources is prevalent to produce clean water for human consumption and sanitation. Solar still is a water distillation method that uses solar energy as a heat source to produce fresh water. Selection of a solar still condensing cover material remains a challenge, particularly for enhancing the condensate formation and collection. Therefore, this research proposed the application of a mixed wettability surface on the solar still condensing cover. A water-based silicone coating is used on a glass cover with different surface areas. Furthermore, utilisation of thermoelectric water-cooling system with varying cooling power was included to further enhance the rate of condensation on the solar still cover. Comparison in solar still performance between the use of mix wettability cover and other commonly used cover materials which includes uncoated glass, polycarbonate (PC) and acrylic (PMMA) with thermoelectric cooling was conducted. For solar still without cover cooling, the addition of coating showed improvement to the solar still productivity with the highest freshwater output at 30% coated surface area. For solar still using water cooling without thermoelectric, the productivity was enhanced by 10% and 26% for glass cover and mixed wettability cover, respectively but reduced by 21% and 22% for solar still using PC and PMMA cover, respectively when subjected to low solar radiation. Increasing the thermoelectric cooling power from 12 W to 36 W increased the solar still productivity for glass and mix wettability cover to 76% and 126%, respectively compared to the reference solar still. However, PMMA and PC covers had lower productivity compared to the reference solar still by up to -48% and -82%, respectively. A detailed analysis on the energy, exergy, environment and economic of the solar still using mix wettability cover and thermoelectric cooling showed that the system had an energy and exergy efficiency of 14.3% and 4.3%, respectively using 36 W cooling power. While the cost per litre, CO2 mitigation, enviro-economic and exergo-economic was found to be 0.036 $/L, 2.97 tonnes CO2, $ 83.21 and 4.64 kWh/$, respectively. Hence, the research outcome highlights the superior performance of using mix wettability surface combined with thermoelectric cooling for solar still application.

Actions (For repository staff only : Login required)