Energy, exergy and environmental assessment of solar still with solar panel enhanced by porous material and saline water preheating

Abstract

An assessment of hybrid solar desalination system consists of solar panel integrated with single slope solar distiller improved by salty water preheating and porous material via productivity, energy, exergy, exergoeconomic and exergoenvironmental is performed under metrological conditions of Alexandria, Egypt. Water preheating is performed by passing it over the solar panel front surface before it enters the still basin, which is also used as solar panel cooler. The panel integration is performed by installing it directly over the still back wall. Solar panel power is used to heat up further the salty water. Moreover, the impact of utilizing black steel wool fibers in the still basin on the system performance is studied. Results illustrate that preheating 40%, 50%, and 60% of the salty water rises solar desalination system freshwater yield by 10.4%, 15.5%, and 20.9%, energy efficiency by 8.2%, 13% and 20% and exergy efficiency by 26.86%, 33.51%, and 60.64%, respectively. Using black steel wool fibers increases conventional solar still and solar desalination system production without and with 60% preheating by 17.8%, 13.7%, and 11.8%, energy efficiency by 13.58%, 9.73%, and 13.5% and exergy efficiency by 16.51%, 10.27%, and 32.45%, respectively. Solar desalination system with black steel wool fibers and 60% of water preheating achieves the highest performance based on freshwater yield, cost, energy payback time, exergoeconomic, exergoenvironmental and exergoenviroeconomic parameters. With these positive results and the available solar energy in Egypt, the current system can be a promising nation strategy in saline water desalination and power production. - Preheating 60% of the salty water rises freshwater yield by 20.9% compared to solar desalination system without preheating (0%). - Using BSWF increases freshwater yield of the system without preheating (0%), and with 60% preheated water by 13.7%, and 11.8%, respectively. - Preheating 60% of saline water, enhances energy and exergy efficiency without preheating (0%) by 20% and 112.8%, respectively. - System with BSWF and 60% preheated has minimum freshwater production cost and system without preheating (0%) has the highest. - SDS+BSWF (60%) migrates the maximum amount of CO2 based on environmental and exergoenvironmental of values of 27.98 and 2.2896 tons, respectively.