Techno-economic investigation and dual-objective optimization of a stand-alone combined configuration for the generation and storage of electricity and hydrogen applying hybrid renewable system

In this study, a solar driven co-generation structure of hydrogen and electricity is techno-economically investigated to be installed in the Farakhi village. In addition, a combined renewable configuration is also designed and integrated to the proposed system so as to provide required direct current for utilization in solid oxide electrolyzer. The presented scheme is modeled and simulated by MATLAB, ASPEN HYSYS, and HOMER Pro software. Economic, exergy as well as exergoeconomic approaches are applied to determine and to monitor the performance of the system and also to specify prominent factors through sensitivity analysis. The annual capital cost, yearly maintenance cost, and yearly operating cost of system were 15584.784 $/year, 455.062 $/year, and 245113 $/year, respectively. The system produced 29.2 ton of hydrogen per year, with a LCOP of 8.94 $/kg H2. The yearly cost of the system (ACS) was determined to be 261153 $/year. The largest amount of exergy destruction was related to reactor of the SOEC sub-unit with a value of 22.9 kW, which accounts for 47.33% of the total exergy destruction in the system. Moreover, the greatest share in the irreversibility of the whole combined renewable configuration was related to photovoltaic modules with a value of 86.62% and then biogas generator with a value of 8.03%. The largest and least values of exergoeconomic factor belonged to the solar collectors (100%) and reactor (9.91%), respectively. Ultimately, the economic, exergy, and exergoeconomic parametric analyses were carried out to generalize the results of the presented study to other geographical locations. The values of current density, operating temperature of SOEC, voltage of SOEC and temperature of fluids leaving the thermoelectric generator at the optimum point were determined to be 0.337 A/cm2, 791.5 degrees C, 1.212 V, and 197.5 degrees C, respectively.