Thermodynamic and economic analyses of hydrogen production system using high temperature solid oxide electrolyzer integrated with parabolic trough collector

In this paper, solar energy is used to produce hydrogen through high temperature electrolysis process. Usually PV modules are used to produce the required electricity. But efficiency of the PV panels is low and it reduces by increasing ambient temperature. To overcome this issue, parabolic trough collector is used in this study to provide both thermal and electrical energy for the electrolyzer. To evaluate performance of the system, energy, exergy and economic analyses are conducted. Finally, sensitivity analysis and multi-objective optimization process are performed to analyze thermodynamic and economic performance of the system simultaneously. The results showed that under design condition, the system is capable of producing 0.003 kg/s hydrogen. Exergy analysis indicated that solar collector and thermal storage tank have the highest rate of exergy destruction with almost 80% of total exergy destruction of the system. Sensitivity analysis showed that the value of current density for the electrolyzer should be selected carefully as it has considerable effect on techno-economic performance of the system. Finally, optimization results showed that the highest achievable exergy efficiency of the system is equal to 26.81%, while the lowest levelized cost of hydrogen is 4.43 $/kg. (C) 2018 Elsevier Ltd. All rights reserved.