Innovative geothermal-based power and cooling cogeneration system; Thermodynamic analysis and optimization

Among different types of geothermal processing used in the energy conversion systems, flash-binary geothermal can be the best scenario for cogeneration purposes. Thus, a new combined cooling and power generation system is designed based on the flash-binary geothermal heat source. In the devised plant, an internal combination of the organic Rankine cycle and ejector refrigeration cycle is applied as the binary subsystem. Another advantage of the proposed cooling and power system is the profiting of zeotropic mixtures advantageous in the binary unit. The feasibility of the proposed system is analyzed from the energy and exergy viewpoints. Then, the genetic algorithm is employed to optimize the performance of the proposed plant. The optimization process results in some precious facts, likewise increment in total cooling capacity, net output power, energy efficiency, and also exergetic efficiency. The optimized values obtained for the mixture of Pentane (0.533)/Butane (0.467) with the cooling capacity of 330.7 kW, net output power of 1.687 MW, thermal efficiency of 19.20%, and exergy efficiency of 53.27%. Moreover, among all the components of the binary unit, the highest exergy destruction rate belongs to the generator and ejector, respectively.