Exergy Destruction Research Articles

Thermodynamic and exergetic evaluation of CO2 liquefaction for ship transport

CO2 liquefaction is significant to ensure CO2 transport safety and improve efficiency. Aiming at the temperature and pressure required for ship transport, this paper examines four liquefaction schemes including the compression refrigeration system, the Linde Hampson system, the precooled Linde Hampson system and the Claude system. The thermodynamic and exergetic ananlysis models are established primarily and total power consumption, liquefaction efficiency as well as exergy efficiency of the four systems are calculated and compared. The precooled Linde Hampson system shows the best performance with the three indicators of 391.74 kJ/kg, 97.97 % and 55.86 %, respectively. Additionally, exergy destruction among the system components are analyzed for Linde Hampson system and precooled Linde Hampson system. The maximum exergy destruction stem is from compressors. Another thing to note is that the proportion of the total exergy destruction with Joule-Thomson (J-T) valves are 19.38 % and 2.63 %, respectively. Furthermore, the replacement of the J-T valve by a liquid expander allowed for 9.35 % and 0.94 % electric power saving for the two systems, respectively. The pressure drop before and after the J-T valve directly determines the effect of this change. The research results could provide some vital reference for choosing proper CO2 liquefaction methods and reducing energy consumption during the process.

Thermoeconomic analysis for hybrid solar Brayton cycles operating with different working fluids

A Brayton cycle analysis with regeneration fed by heat input from a central concentration solar energy tower and a combustion chamber that uses natural gas is presented. The thermodynamic model includes the irreversibility of the different components of a conventional Brayton cycle system and a solar concentration system through energy and exergy considerations. The environmental conditions of Barranquilla are used for the plant analysis using different working fluids throughout the day, where the carbon dioxide cycle presents an overall efficiency of 28.8 %, the cycle with air efficiency is 26.6 %, and the Helium cycle is 20.2 %. The model considers the energy flows within the plant and the exergy destruction. In this sense, the solar concentration system contributes an energy fraction of 0.209 when operating with air, while the exergy destruction fraction is 0.189 when operating with carbon dioxide when solar radiation is maximum. Finally, an estimation of the Levelized Cost of Energy is presented.

Exergy analysis and improvement of helium internal purifier

Exergy analysis was applied to the evaluation of helium internal purifier in this paper. The important operating parameters has been given to determine the exergy destructions in components as well as in the entire cycle of internal purifier. The analysis results show that the recovery of liquefied air energy can improve the performance of purifier and the exergy destruction of different heat exchanger is different. Results from the analysis helped evolving guidelines for designing appropriate technological process for practical helium internal purifier. An internal purifier with an optimized structure was designed to remove air impurities up to 10 mol%, beyond previous maximum impurity content. The impact on liquefaction capacity is minimized because of the small consumption of cold flow. The achievable performance was also provided in this paper. The purifier could remove air impurities up to 8 mol%.

Power plant systems performance assessment with applications of combined pinch and exergy analysis

Steam power plants forms an effective share of global electricity production. Thus, improving such plants performance is crucial to minimize its environmental effects and to enhance operational economy. Al-Mosyab thermal power station in Iraq is considered as a case study of this paper, with an objective of achieving best system performance. A combined pinch & exergy analysis (CPEA) is conducted under actual operating conditions. Further analytical attempt is varying pressure (165, 175, 185) bar, and temperature (450, 550, 620) °C at selected cycle location. Examining thereby the impact of each variable on the system power output, exergy destruction and 2nd low efficiency. The Engineering Equation Solving program (EES) is used for the simulation of each system components under these various operating conditions. The yielded results showed that the maximum mechanical & thermal output are (36.75 & 94.88) % of fuel energy respectively, while, turbine, boiler and condenser irreversibility and 2nd law efficiency are (157.76, 1086.18, 303.19) kJ/kg) and (88.36, 68.97, 28.68) % respectively. The analytical part of the analysis however showed that the high-pressure turbine network output increases by about (1%) with pressure variation, while such increase rise up to (70%) with temperature variation. Final concluded results predicted that best performance could be obtained at maximum pressure and temperature of (175) bar and (620) °C respectively.

Thermodynamic, exergoeconomic evaluation and optimization of S–N2O/t-N2O nuclear power cycle for the construction of the lunar base

With the continuous development of deep space exploration, many planetary exploration schemes and development plans regard the construction of planetary bases as an essential goal, especially the exploration of the Moon. Supercritical and transcritical nitrous oxide (N2O) cycles are compact, low-cost, efficient, and lightweight for nuclear reactors to supply power to the bases on other planets. This paper presents the thermodynamic, exergoeconomic, and mass analyses of a combined cycle consisting of a supercritical N2O recompression Brayton cycle and a transcritical N2O cycle (S–N2O/t-N2O). It is shown that under the optimal conditions, the combined thermal efficiency and exergy efficiency are 45.52 % and 60.13 %, respectively. Based on the exergy analysis, the exergy destruction mainly occurs in the reactor and main compressor. A sensitivity study shows that the split ratio, pressure ratio in the supercritical N2O cycle, main compressor inlet pressure, turbine2 inlet temperature, and turbine2 inlet pressure have significant effects on the net output work, thermal efficiency, specific mass, and levelized cost of electricity. Furthermore, multi-objective optimizations are considered to obtain the Pareto frontier solutions for different multi-objectives, and the optimal design condition is found. These findings could improve the power cycle performance for the construction of the Lunar Base.

A comparative evaluation of energetic and exergetic performance parameters in syrup purification and evaporation lines

AbstractConsidering the global challenges of environmental destruction, limited fossil reserves, and the reduction of the share of energy in the final price of the product, a detailed evaluation of energy‐intensive systems is needed to improve performance. The syrup heating process is one of the basic processes in sugar factories. In this study, the syrup heating system in the purification and evaporation lines, located in the Urmia sugar plant, was evaluated, analyzed, and compared with energy and exergy analysis. Also, the subsystems of the syrup heating process were evaluated with thermodynamic analysis. Mass, energy, and exergy balances were carried out by coding in EES software, and energetic and exergetic operational parameters were extracted. The heat loss rate and exergy destruction rate in the syrup heating system of the purification line were calculated as 121.29 and 404.36 kW, respectively, and in the syrup heating system of the evaporation line as 112.70 and 238.62 kW, respectively. The recovery potential rate was 134.99 kW for the purification line and 37.70 kW for the evaporation line. The stability index and exergy efficiency for the purification line were calculated as 3.03% and 67.01% for the purification line and 6.54% and 84.71% for the evaporation line. The results of the thermodynamic analysis showed that the syrup heating process in the purification line has weaker performance from the energetic and exergetic point of view, is accompanied by large losses, and imposes a greater environmental burden. Accordingly, it is suggested that the improvement of the syrup heating performance in the purification line should be prioritized for engineering optimization and redesign in sugar processing plants.Practical applicationsMonitoring the operational state of the systems and determining system losses are critical steps in food thermal processing. A practical and accurate method to evaluate the purification and evaporation lines is required to improve the thermal efficiency. According to exergy analyses, the performance of the syrup heating process in the purification line is low due to large losses and imposes a greater environmental burden. Therefore, the improvement of the syrup heating performance in the purification line should be prioritized for engineering optimization and redesign in sugar processing plants.

Performance analysis of a novel air source ammonia/water cascade heat pump for heating buildings in subarctic climate

Performance of available air-source heat pumps (ASHP) for buildings is extremely influenced by the outdoor air temperature (OAT). When OAT falls below –20 °C, especially in subarctic climate, most commercially available ASHPs lose their defined functionality. To address this issue, a novel cascade heat pump (CHP) is proposed that utilizes two natural (with zero global warming index) refrigerants: ammonia, aka R717, as the low stage (LS) refrigerant, and water, aka R718, as the high stage (HS) working fluid. The proposed system is equipped with two rotary vane compressors for LS and HS. To desuperheat the compressor discharge temperatures and increase the HS heating capacity, liquid refrigerant is injected into the chamber of both LS and HS compressors. The wet compression is thermodynamically modeled and validated against experimental data available in the literature. Optimum design parameters such as the maximum allowable temperatures during compression and the minimum vapor quality after injection are obtained where the COP is maximized. Total exergy destruction, number/location of injectors and the injected amounts are also investigated. The proposed CHP can deliver 6.35 kW heating load at 50 °C with a COP of 1.985 when OAT is –40 °C. From a broader perspective, the proposed CHP not only proves its efficacy in extremely cold subarctic climates but also emerges as a pivotal player in addressing the global warming issue. This is accomplished through a dual approach to decarbonization—firstly, by electrifying heating processes and secondly, by substituting phased-out refrigerants with environmentally friendly natural alternatives.

Exergy-based method for evaluating the dynamic optimization of a supercritical water fluidized bed

Dynamic optimization of hydrogen production from coal gasification within an industrial-scale supercritical water fluidized bed is studied. Coal slurry and supercritical water mass flow rates are selected as the manipulated variables to investigate the optimal operation for scenarios involving variations in hydrogen demand. For the temperature-constrained scenario, supercritical water mass flow rate and temperature are manipulated. The results demonstrate that the optimal time-dependent profiles of the manipulated variables enable the supercritical water fluidized bed to meet variable demands of hydrogen and improve availability. Dynamic exergy methods are implemented to assess the thermodynamic behavior of different optimization schemes for efficient operation. The results show that more attention should be paid to the process of adjusting the mass flow rates of coal slurry and supercritical water simultaneously to vary the hydrogen yield because it requires the largest energy consumption. Manipulating the supercritical water mass flow rate causes less exergy destruction at a temperature constraint of 600 °C, but more exergy destruction at a temperature constraint of 700 °C.

A Novel Designation of Solid Oxide Fuel Cell-Integrated System Using LPG as Fuel for Marine Vessels

A Novel Designation of Solid Oxide Fuel Cell-Integrated System Using LPG as Fuel for Marine Vessels

Comparative exergy and economic analysis of deep in-situ gasification based coal-to-hydrogen with carbon capture and alternative routes

The deep in-situ gasification based coal-to-hydrogen (deep IGCtH) is attracting attention for its unique advantage in utilizing unrecoverable coal seam. In this paper, its improvement scope in energy conversion and utilization is analyzed using advanced exergy analysis, and the efficiency from cumulative exergy consumption (CExC) perspective and economic competitiveness with Lurgi surface gasification based coal-to-hydrogen (Lurgi SGCtH), coke-oven gas-to-hydrogen (COGtH) and natural gas-to-hydrogen (NGtH) are compared. Results indicate 39.9 % and 25.1 % of the exergy destruction of deep IGCtH and Lurgi SGCtH are unavoidable, while steam methane reforming and coal gasification possess the largest improvable potential, with avoidable endogenous/exogenous destruction of 96.63 MW/81.58 MW and 162.52 MW/151.19 MW, suggesting thermodynamic improvement can also be achieved by improving other components or optimizing process structure in addition to increasing its own efficiency. The CExC of deep IGCtH outputting 1 kg hydrogen is only 83.6 % that of Lurgi SGCtH, indicating it is more efficient route with significantly energy consumption reduction and can better demonstrate its efficiency advantage under large production capacity condition. The deep IGCtH shows only 68.7 % that of Lurgi SGCtH in investment and also presents significant advantage in cost. However, its profitability advantage over NGtH loses with hydrogen price increasing and there exists lower limit on capacity of 0.46 billion Nm3 to maintain cost and profitability competitiveness over COGtH. Furthermore, deep IGCtH shows emission reduction cost advantage over Lurgi SGCtH when capture rate exceeds 80 %, and profitability will not be limited by carbon tax and coal seam thickness within the considered range.

Can injecting additional green hydrogen result in environmentally friendly solar-biomass integration? Comprehensive comparison and multi-objective optimization

The present work proposes an innovative system for decarbonizing the energy mix and accelerating the worldwide green transition process. The system is driven by a biomass digester integrated with the supercritical carbon dioxide cycle for power generation and a multi-effect desalination unit for drinkable water production. At the heart of this concept is additional hydrogen injection through a proton exchange membrane electrolyzer based on photovoltaic panels. The suggested innovative model's techno-environmental, sustainability, and economic aspects are assessed and compared with a similar system without hydrogen injection. Then, a comparative multi-criteria optimization is applied to find the most optimal conditions from various facets based on the genetic algorithm with machine learning techniques. Afterward, the system’s performance at different optimal conditions is analyzed and compared by evaluating the most significant techno-economic, environmental, and sustainability indicators. The parametric assessment comparing different models indicates that the proposed novel model, including increased hydrogen injection, surpasses the basic system in terms of performance efficiencies, emissions, and energy costs. In the first optimization scenario, the proposed method demonstrates robustness by achieving higher water production of 1456 kg/s, a lower total cost of 118 $/h, and a higher net power of 1.1 MW than the design condition. When considering the sustainability index, energy cost, and emission metric as the optimization objective, their values are altered from 0.81 to 0.85, 92.5 $/MWh to 89.7 $/MWh, and 64.2 kg/MWh to 53.6 kg/MWh. The results further show that when prioritizing the sustainability index, energy cost, and emission as objectives, all components perform better from the energy conversion quality aspect compared to the scenario where water production, total cost, and net power are the optimization objectives. Finally, it is observed that the combustion chamber and solar panels are the worst components from the irreversibility aspect because of the highest exergy destruction rate.

Thermodynamic analysis of natural gas/hydrogen-fueled compressed air energy storage system

In this paper, a diabatic compressed air energy storage system fueled by a natural gas/hydrogen mixture that integrates heating and power generation is proposed. A comprehensive thermodynamic analysis has been conducted to identify the key factors influencing system performance and elucidate the detailed formation and distribution patterns of irreversible losses when utilizing a hydrogen-natural gas blend as fuel in the proposed system. The research results indicate that increasing the hydrogen blending ratio from 0.5 to 1 lead to greater enhancements in roundtrip efficiency (∼1.08% vs. ∼0.33%), exergy efficiency (∼3.88% vs. ∼1.15%), and energy density (∼1.24% vs. ∼0.42%) compared to an increase from 0 to 0.5. The combustor suffers the largest exergy destruction proportion, with a notable reduction in exergy destruction achieved through increased hydrogen blending. System performance benefits significantly from higher combustor outlet temperatures and expansion ratios at various hydrogen blending ratios. The rate of change in exergy efficiency (∼42.76% vs. ∼83.17%) and energy density (∼58.83%) demonstrates an inverse correlation with the varied parameters (1100–1500K, 4–8), except for the rate of change in energy density (∼6.76%), which displays a positive relationship with the combustor outlet temperature. Notably, a significant decrease in the rate of change in roundtrip efficiency (∼1.87% vs. ∼6.64%) is observed within a specific parameter range (1400–1500K, 5–6). Sensitivity analysis identifies the combustor outlet temperature as the most influential factor in enhancing system performance, consistently showing positive effects of the hydrogen blending ratio.

Process arrangement and multi-aspect study of a novel environmentally-friendly multigeneration plant relying on a geothermal-based plant combined with the goswami cycle booted by kalina and desalination cycles

In this study, a novel trigeneration system for cooling, heating, freshwater, and electricity generation, driven by geothermal energy is evaluated from thermodynamics, thermoeconomic, and environmental perspectives. To gain a better understanding of the system's performance, energy and exergy analyses are conducted, and the outcomes are compared with other studies. The proposed structure includes a single-flash geothermal plant, a water desalination unit, the Goswami power and cooling cycle, and the Kalina power cycle. This analysis is conducted using Aspen HYSYS software, and the results demonstrated that the single-flash geothermal plant has the highest irreversibility (48 %), and the major sources of irreversibility among all equipment are the heat exchangers, contributing to 68 % of the total exergy destruction rate. Additionally, it is observed from the thermodynamic analysis results that the energy and exergy efficiencies and the total unit cost of products of the proposed process are 32.28 %, 51.71 %, and 5.66 $/GJ, respectively. According to the results, the production rate of the products is cooling (24.8 m3/h), steam (27.44 m3/h), domestic hot water (209.7 m3/h), fresh water (45.02 m3/h), and electric power (16260 kW). The environmental analysis shows that the new process has zero CO2 emission and can save an annual consumption of petroleum equal to 4325160 L, and when compared to the power plants with natural gas and oil as fuel, CO2 emissions are prevented equal to 5691000 kg/year and 13804740 kg/year, respectively.

4E assessment of ejector-enhanced R290 heat pump cycle with a sub-cooler for cold region applications

Currently, the worldwide implementation of the Montreal Protocol has accelerated the development of low GWP refrigerants. R290 as an alternative refrigerant with low GWP has great advantages over R134a for heat pump applications. However, the use of expansion valve throttling in the heat pump cycle has a large irreversible loss. Therefore, an ejector-enhanced sub-cooler vapor injection heat pump cycle (ESVIC) with R290 for water heating is proposed in this paper to improve the energy efficiency by applying ejector. The thermodynamic models are established based on the 4E (energy, exergy, economic and environmental) analysis to compare its performance with the basic ejector-enhanced heat pump cycle (BEEC) and the sub-cooler vapor injection heat pump cycle (SVIC). The energy analysis results show that compared with the BEEC and SVIC, the volumetric heating capacity of the ESVIC is improved by 42.0 % and 21.2 %, and the heating coefficient of performance (COPh) of the ESVIC is improved by 27.6 % and 5.3 %, respectively. The exergy analysis results indicate that in BEEC, SVIC and ESVIC the exergy destruction of the expansion valves is 0.3 %, 13.5 % and 0.8 %, respectively. It is indicated that the adoption of ejector can significantly decrease the exergy destruction of expansion valves. Moreover, the environmental analysis results reveal that the carbon emissions of ESVIC is 21.5 % and 5.0 % lower than those of BEEC and SVIC, respectively. Besides, for the ESVIC system, the carbon emissions of the life cycle climate performance when using R290 are 9.9 % lower than that of using R134a, indicating that the R290 is a potential substitute for R134a in heat pump applications. The economic analysis results demonstrate that the unit exergy production costs of ESVIC is 21.6 % and 5.1 % lower than BEEC and SVIC, respectively.

Energy and Exergy Analysis of an Ejector Expansion Transcritical Carbon Dioxide Air Conditioning System

A carbon dioxide based transcritical air conditioning system integrated with an ejector is thermodynamically modeled and the system is simulated for different ambient conditions. Throughout the analysis, the isentropic efficiency of motive nozzle, suction nozzle and diffuser is assumed as 85% while the mixing takes place at constant pressure. A step-by-step iterative procedure is adopted to obtain the pressure lift and entrainment ratio. The present thermodynamic model is validated with the experimental results available in the open literature. Results were then compared to a conventional transcritical carbon dioxide system working between the same operating conditions. Results show a significant improvement of about 21% and more in system performance compared to a conventional system working under the same operating conditions. To justify the application of an ejector as an expansion work recovery device and to identify the component level exergy destruction rate, a comprehensive exergy analysis is implemented and the results show 20% reduction in total exergy destruction rate of the system, with an ejector.

Experimental study and exergy analysis of electric vehicle single-stage compression secondary throttling CO2 air-source heat pump system in cold climate

A novel CO2 air-source heat pump system (ASHPs) with a secondary throttling based on a single-stage compression was proposed to further improve the heating energy efficiency of electric vehicles (EVs) for heating in cold climates. The heating characteristics of the secondary throttling system (STS) and conventional throttling system (CTS) at different indoor air supply temperatures were compared. The STS performance characteristics were investigated under varying ambient temperature, outdoor air velocity, and exergy analysis was performed on the system and its components. A fitting correlation equation for optimal discharge pressure was obtained based on experimental data. The results demonstrate that implementing STS significantly reduces CO2 ASHPs energy consumption (Wcom), enhances the coefficient of performance (COP), and reduces exergy destruction. When the indoor air supply temperature reaches 45 °C, using STS can result in an 8.1 % reduction in Wcom, a 9.4 % increase in COP, and a 6.1 % improvement in the exergy efficiency (Exη) compared to that of CTS. Furthermore, the advantages of STS become more pronounced with higher indoor target air supply temperatures. As the ambient temperature decreases, the exergy efficiency of the STS reaching the target air supply temperature decreases. The velocity of outdoor air significantly affects the STS performance, and increasing outdoor air velocity can effectively enhance the Exη of STS. The optimal discharge pressure fitting equation for the STS was obtained through multiple linear regression analysis. These findings can provide ideas for architectural optimization and design of CO2 ASHPs for EVs, which are important for further improving system performance.

Techno-exergy-economic assessment of humidification-dehumidification/reverse osmosis hybrid desalination system integrated with concentrated photovoltaic/thermal

Desalination is a process used to generate water for human consumption, irrigation, or industrial purposes. Assessment of desalination plants is crucial for freshwater productivity, energy consumption, exergy destruction, and economic feasibility calculations. Therefore, the study aims to conduct a technical, exergy, and economic analysis of a concentrated photovoltaic/thermal hybrid humidification-dehumidification reverse osmosis desalination system. The photovoltaic/thermal provides the electrical and thermal requirements for the hybrid desalination unit. Theoretical models for each unit are developed and integrated using the Engineering Equation Solver software. The sensitivity of system performance parameters was investigated under different climatic and operation factors. The analysis shows that the system produces 860 L per hour at the lowest specific energy consumption and water cost (3.3 kW-hours per cubic meter and 0.916 United States dollars per cubic meter), respectively, with a cost payback period of only 12 years compared to other green-powered desalination systems. The highest destruction portion of 84.6 % is at photovoltaic/thermal, while the largest cost portion of 68 % is at reverse osmosis. Productivity, energy consumption, and water cost are influenced by feed salinity, while destruction is most affected by solar irradiance. Ambient temperature, wind speed, and cooling fluid flow rate slightly affect the techno-exergy-economics of the system.

3E analyses and multi-objective optimization of a liquid nitrogen wash based cogeneration system for electrical power and LNG production

A liquid nitrogen wash based novel system is proposed for electricity generation and LNG production. This system utilizes cold energy of methane rectification for power generation, and realizes the LNG production through methane recovery from exhaust gas. Effects of operational parameters on net generation capacity (NEG) and energy efficiency are studied. Exergy destruction/efficiency and exergy cost are obtained. Advanced exergy/exergo-economic analyses are conducted to clarify the improvement potential and improvement strategy. Finally, the optimal solutions are obtained in multi-objective optimization. Results show that propane could be used as the organic working medium and the maximum NEG is 675.95 kW and the energy efficiency is 19.34 %. As 88.8 % of the system investment cost is for the equipment, reduction on exergy destruction cost of equipment should be considered. Advanced analysis indicates that 27.27 % of the exergy destruction, 30.02 % of the exergy cost and 7.20 % of the investment cost can be avoided. The thermodynamic optimization shows that the highest energy efficiency is 67.26 %, the highest exergy efficiency is 76.95 % and the lowest exergy cost per unit is 28.45 $/GJ. The economic optimization shows that exergy efficiency is improved by 2.83 % and NEG is improved by 47.95 % when increasing the investment cost for 6.13 %.

Multi-criteria optimization of a combined power and freshwater system using modified NSGA-II and AHP-entropy-topsis

This paper proposed an innovative hybrid system to generate electricity and fresh water with higher energy efficiency. A subsystem is employed by integrating DCMD and heat pump to recover waste heat of PEMFC to produce fresh water. The thermodynamic and exergoeconomic models are established to evaluate the system comprehensive performance. Compared with the PEMFC alone, the results demonstrated that the proposed hybrid system achieves a 42.07 % increase in energy efficiency and provides 177.86 kg/h of fresh water. The components with high exergy destruction are PEMFC, Relief value, Inverter, Separator 2 and DCMD with the exergy destruction rate of PEMFC stack accounting for 54.55 %. The parametric analysis results indicate that the variation of the membrane filament number, feed and permeate flow rates all have evident impacts on the thermodynamic and economic performances of the hybrid system. The multi-objective optimization is conducted by adopting NSGA-II and three decision-making methods. The optimal solution obtained by AHP-entropy-TOPSIS approach for the net power out, exergy efficiency, WPC, and total exergy cost rate are 96059W, 0.5293, 0.2995 $/m3, and 14.27 $/h, respectively. In addition, the obtained results shown that the simulation times of NSGA-II are significantly reduced from 89.30 to 11.20 h by introducing BP-ANN to improve the simulation efficiency.

Optimal 4E evaluation of an innovative solar-wind cogeneration system for sustainable power and fresh water production based on integration of microbial desalination cell, humidification- dehumidification, and reverse osmosis desalination

Reliable freshwater production is vital for tackling two of the most critical challenges the world is facing today: climate change and sustainable development. Present work presents an innovative cogeneration system based on solar and wind energies for sustainable production of freshwater, power, and wastewater treatment. For freshwater production and wastewater treatment in this system, the integration of a microbial desalination cell with a humidification-dehumidification and reverse osmosis desalinations has been used. The mentioned systems provide their heat demand from solar energy, and when solar radiation is unable to provide this heat, a hydrogen internal combustion engine drive produces the required heat for the freshwater plant. Excess heat from the hydrogen internal combustion engine is fed into the organic Rankine cycle for more power generation in the whole system to reduce system waste heat and increase efficiency. PEM electrolyzer has been used to supply the hydrogen needed by the internal combustion engine, and this system uses wind turbines to supply the power demand. To evaluate the performance of the whole system, energy, exergy, exergeoeconomic, and exergoenvironmental (4E) analyses have been carried out. Finally, to improve the performance parameters of the system, multi-objective optimization using the Salp swarm algorithm has been used. Investigation of the results show that the proposed system can produce 720 kW of electricity and 5.36 m3/h of freshwater. The energy efficiency of the system is 22.09 %, and its overall cost rate and overall environmental impact rate are 540.33 $/hr and 17.37 Pt/h, respectively. Among the qualitative results obtained in this research, it is possible to mention the high exergy destruction, cost destruction, and environmental impact destruction of the internal combustion engine compared to other equipment used in the proposed system, and this point shows the need to improve this equipment, similar to previous researches. The five-objective optimization results of the proposed system showed that the performance parameters of the system, such as polygeneration energy efficiency, total cost rate, and total environmental impact rate, can be improved by 6.2 %, 1.44 %, and 0.52 %, respectively. The payback period of the proposed system in the optimal state is 6.95 years.