Geothermal and solar energy utilization for the development of a sustainable power and cooling production

The growth of power demand and environmental issues of fossil fuels lead to renewable energy utilization. A novel combination of parabolic trough solar collectors with a double-flash geothermal system is proposed to generate power and cooling simultaneously. Two parabolic trough solar collectors are employed; the first one directly supplies the solar heat during the day and the second one stores the solar heat for the night operating time. Zeotropic mixtures in an integrated ejector refrigeration-organic Rankine cycle are employed to improve waste heat recovery and overall performance. Exergy and exergoeconomic assessment criteria are employed to evaluate the performance of the designed plant. The subsystem's working fluid selection was performed by comparison of the performance of six zeotropic mixtures. The parametric investigation reveals that the exergetic efficiency and net power are affected by the inlet pressure of the separators, and direct normal irradiation presents the highest effect on the payback period. Moreover, the system's optimum state is evaluated by a multi-objective optimization scheme.