Results revealed that increasing the LHV of the biomass results in a decrement of both energy and exergy efficiencies of MGS and recovery ratio. The influence of expander I on energy and exergy efficiencies of the CO 2 cycle was investigated. The proposed MGS produces 73.17 GWh of cooling, 103 GWh of electrical energy, 1223 Ton of NaOH, 1114 Ton of HCl, and 212.6 m 3 of potable water annually. The highest and lowest exergy destruction rates (EDR) belong to the liquefied natural gas line and elec-trodialysis, respectively. The obtained energy and exergy efficiencies of modeled MGS are 75.1% and 88.4%. A parametric study regarding moisture content of biomass, the efficiency of expander I, LHV of biomass, the salt concentration of seawater, and a number of MED effects on system performance was conducted. This integrated system produces electricity, cooling, distilled water, sodium hy-droxide (NaOH), and hydrogen chloride (HCl). The combined system composed of biomass gasifier, CO 2 cycle, cooling system, multi-effect distillation (MED), and electrodialysis was assessed. In this study, a novel multigeneration system is considered from energy, exergy, and economic points of view. The same approach is applied in this paper, highlighting the differences and the difficulties related to the variation of the reference pressure and temperature in the reference environment. The Gouy-Stodola Theorem is also used in various textbooks for defining the flow and the non-exergy of a control volume. In this way the Gouy-Stodola Theorem still holds, but the allocation of exergy destruction is generally different from that calculated in the usual hypothesis of constant temperature and pressure of the reference environment. These additional terms take into account the potential useful work (exergy) destruction related to the variation of the ambient condition during the considered time interval. The equations that have been derived taking into account the variation of reference temperature and pressure show that two additional terms appear in both reversible and irreversible maximum useful work output, besides the well-known terms. The well-known theorem is re-obtained in this paper, relaxing the hypothesis about a constant value for temperature and pressure of the reference environment. The Gouy-Stodola Theorem is the theoretical basis for allocating irreversibility and for identifying the maximum possible efficiency for any kind of energy conversion system.
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