Sea-water desalination using a desalting unit integrated with a parabolic trough collector and activated carbon pellets as energy storage medium

Solar energy is considered the most influential source for various sustainable applications and its utilization can effectively convert brackish water into freshwater. The present work explores a novel method of augmenting the water productivity of the desalination unit using sea-water as the feed water through integrating a parabolic trough collector (to preheat the water supplied to the still basin) and activated carbon pellet (a highly porous energy storage material) to improve the rates of evaporation and water production. Experimental results revealed that the full-day water yield was augmented by 50.21% for the modified desalination unit, as compared to the conventional unit. 24-Hours water yield of modified solar still was increased by 85.2% compared to the conventional unit, owing to the synergetic effect of the parabolic trough and porous carbon. However, the integration of the parabolic trough collector significantly reduced the energy and exergy efficiency of the modified unit. The economic analysis estimated that the cost of the produced clean water was 0.010 US $ per liter for the modified unit, with a payback period of 66 days. Moreover, it was found that the modified desalination unit configuration can reduce CO₂ emissions by 18.74 tons during its lifespan.