Energy, exergy and exergo-environment analyses, and tri-objective optimization of a solar still desalination with different insulations

Abstract

One of the most substantial aspects of the solar still systems that should be significantly considered is their economic and environment aspects. The present study deals with analyzing and identifying the behaviors of a cascade solar still desalination system in the presence of different insulation types and phase change materials. A Matlab code is developed to solve the energy equations for different components of the system simultaneously using ODE-45 solver. A comprehensive thermal, economic and environment analyses performed on the solar still desalination system with different insulation types and phase change materials. With selecting three objective functions namely total annual cost (TAC), exergy efficiency (ηex), and exergy-based CO2 mitigation (φCO2,ex−based), the tri-objective optimization is carried out for two considered cases of solar still desalination units. The thermal analysis represents that among different insulation types phenolic foam with 9.42 kg/m2 per day has the highest value of distilled water production. The total annual cost analysis infers that the system with paraffin as phase change material (PCM) and glass wool as insulation, with 71.67 $, has the lowest TAC. The tri-objective optimization results demonstrate that for both considered cases three objectives are improved considerably compare with non-optimized solar still systems.