Comparative assessment of chloride family hydrogen production cycles driven by a nuclear-geothermal energy system

Abstract

In this present study, a nuclear geothermal hybrid system is designed and integrated three different chloride family hydrogen production cycles: cobalt-chloride, 3-step magnesium-chloride, and 4-step magnesium-chloride cycles. This study aims to investigate the integrated systems with the energy and exergy approaches employing the first and second laws of thermodynamics and compare the hydrogen production potentials of the cycles. The produced heat and electricity by nuclear geothermal hybrid system are employed in the hydrogen production cycles, remained heat and electricity are sent to the community for domestic usage. The nuclear geothermal hybrid system produces 1205.40 MW of heat and 578.56 MW of electricity. The hydrogen production amounts of the Co-Cl, 3- and 4-step Mg-Cl cycles are calculated as 0.27 kg/s, 1.09 kg/s and 0.97 kg/s, respectively. Consequently, the highest overall energy and exergy efficiencies are calculated to be 65.05 % and 88.27 % for the Co-Cl cycle driven by heat only. The integrated nuclear-geothermal hybrid also produces power as a useful output.