Energy analysis desalination of single slope solar still

Abstract

The surface of the evaporator glass in the seawater desalination process by utilizing solar energy as the main energy source is a phenomenon that has been widely studied and developed in order to get increased performance efficiency to produce fresh water. The heat energy from the sun will enter through the surface of the evaporator glass and absorbed by water inside the evaporator, while the evaporator wall is insulated using aluminium foil with a thickness of 20 mm in the hope that the heat energy received will not be wasted around the environment. The process of evaporation of seawater begins when the water has reached the point of evaporation without pressure and occurs naturally. When seawater starts to evaporate, it can be calculated the amount of heat energy absorbed by the water until it reaches the point of evaporation, in order to determine the increase in performance and efficiency of the desalination process. Efforts to improve continue to be done if it is still possible to increase the efficiency and performance of desalination devices with various energy utilization methods. After testing, the highest solar intensity obtained on the test day reached 420.85 W/m2, and the lowest solar intensity on the second day was 96.89 W/m2. The highest evaporation heat transfer coefficient reaches 10.54 W/m2 °C and the lowest is 4.42 W/m2 °C. The highest convection heat transfer coefficient reaches 51.15 W/m2 °C and the lowest heat conversion coefficient is 15.28 W/m2 °C. The total absorbed energy reaches 6.26 kW and the lowest absorbed energy reaches 1.37 kW. Energy efficiency reaching 85% and the lowest energy efficiency is 35%.