Design and Thermodynamic Evaluation of a Solar-Powered CCHP System for Libya's Energy Needs

Libya has an abundant solar energy potential but remains heavily dependent on fossil fuels for electricity generation, leading to energy insecurity, high emissions, and grid instability. This study presents the integration and thermodynamic performance analysis of a solar-driven Combined Cooling, Heating, and Power (CCHP) system designed to address these challenges in the Libyan context. The proposed system integrates a regenerative Brayton cycle for electricity generation, an absorption refrigeration cycle for cooling, and a heat recovery unit for thermal energy. Solar energy is the primary energy source, collected through a heliostat field and a central receiver. The thermodynamic model was developed using Engineering Equation Solver (EES), with Tripoli’s solar radiation data as input. Results show that the system can achieve a maximum total energy efficiency of 73.6% and an exergy efficiency of up to 39.4% under optimal operating conditions. The net electrical power output reached 79.4 kW, while the cooling load supplied by the absorption system was 126 kW with a coefficient of performance (COP) of 0.82. The heat recovery unit delivered 62.5 kW of useful thermal energy. Exergy destruction analysis revealed that the solar receiver and recuperator contributed the highest levels of irreversibility, accounting for 38% and 21% of total exergy destruction, respectively.Monthly performance evaluations confirmed that the system performs best in summer, with peak energy utilization occurring in July when solar irradiance exceeds 850 W/m² and cooling demand is highest. Keywords: Solar CCHP system, Brayton cycle, Exergy analysis, Libya.