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Abstract
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The increasing need of humans for energy and the limited resources of fossil fuels require too much
attention to replacing renewable energies with the energies from fossil fuels. Hydrogen is one of the
most significant renewable energies. Liquefaction is used for storing and transferring this fuel to other
areas. Waste heat can be used in other integrated structures at the time of liquefying hydrogen. In this
study, an integrated structure was developed for the simultaneous production of liquid hydrogen (LH2)
and liquid fuels (LF) using electrolyzer, hydrogen liquefaction cycle, Fischer-Tropsch synthesis, and car-
bon dioxide power cycle. The integrated structure produced 1.157 kg/s liquid hydrogen, 3.756 kg/s liquid
fuels, and 359.8 kg/s hot water. The natural gas to liquid (GTL) process was developed by absorbing the
steam generated from the waste thermal energy of the liquid hydrogen production cycle, the oxygen
produced by the electrolyzer, and natural gas in the reforming reactors and the Fischer-Tropsch syn-
thesis. The GTL process was highly exothermic and the released energy from the liquid fuel production
was used for power production. The specific power consumption of the hydrogen liquefaction cycle was
6.642 kWh/kg LH2. The power to fuel and exergy efficiencies of the integrated structure were 83.75% and
62.54%. The exergy analysis of integrated structure indicated that electrolyzers with a share of 48.05%
and reactors with a share of 15.16% had the maximum amount of exergy destruction. The results of the
economic analysis of the system depict that the period of return and additive value were 3.581 years and
71.39 $/m3 LF.
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