• Physical exergy analysis of a hybrid power plant that generates both electricity and water. • Exergy destruction rate in integrated system components. • The costs of operating a reverse osmosis with thermal disinfection system to purify water. • Thermal analysis of a solar parabolic trough collector to determine the working fluid temperature at the exit receiver. • Sensitivity analysis of to find out the most dominant parameters in the energy conversion process has been carried out. Due to the obvious finite nature of fossil fuels and their environmental impact, renewable energy is becoming particularly crucial. Solar and geothermal energy are consolidated with boiling and reverse osmosis water purification in this research work. Power generation, boiling, and advanced water treatment with improved exergetic efficiency, reduced waste heat, and cost-effectiveness are the goals. The daytime cycle generates electricity and charges thermal energy storage at a 51.64 % exergy efficiency. The night-time cycle's output, boiling water treatment with waste heat and power generation, operates at 49.25 % exergy efficiency. Exergy and sensitivity analysis, solar collector performance parameter determination, and reverse osmosis system modelling are all done with EES, Python, and GPS-X software, respectively. The system met its goal of producing 44 MW of power with an average 50.4 % exergetic efficiency. Thermal disinfection and reverse osmosis produces 100 m 3 /day of water, which consumes 13.36% of total energy. The simulated water quality results from RO system indicated pH, hardness, TDS and alkalinity are observed to be within WHO limit for the influent from lake Ziway considered in this study Finally, controlling heat loss to the environment and replacing outdated system components of the existing unit, whose operating conditions have been employed in the analysis, are multiple alternatives for lowering the exergy destruction rate.