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Greenhouse gas emissions into the atmosphere have had devastating environmental effects, including ozone depletion and global warming. Carbon dioxide (CO2) is widely used in oil and gas plants, the food industry, and as a working fluid in the power industry. Carbon dioxide is liquefied for long‐term storage, to be transported to remote areas, and is used for peak shaving in the power plants. Solar flat plate collectors and wasted heat from the CO2 liquefaction system can be used in power plant systems. Also, the use of nanoparticles in the collectors improves the thermal properties of the working fluid and increases the efficiency of solar collectors. This study has developed a new hybrid system for CO2 liquefaction using Linde–Hampson system, Kalina power generation unit, and flat plate solar collectors. The Linde–Hampson system's dissipated heat and solar collectors are used to supplying part of the power of the CO2 liquefaction system. The combined system produces 9416 kmol/h of liquid CO2 by absorbing 35.97 MW of power. The Kalina power generation unit provides 9.546 MW of power by absorbing 76.98 MW of the CO2 liquefaction cycle's dissipated heat and 91.18 MW from flat plate collectors. Based on the output of exergy assessment, exergy efficiency and exergy degradation of the developed integrated structure are 44.16% and 118.3 MW, respectively. Moreover, significant portions of exergy destruction in the combined process belong to solar collectors (74.68%), heat exchangers (12.47%), and compressors (7.157%), respectively. The use of Al2O3 nanoparticles in pure water has been investigated for heat transfer in flat panel solar collectors. According to the sensitivity analysis results, as the volume ratio of particles in nanofluid increases to 6%, the production capacity of the Kalina cycle and exergy efficiency improves to 9.56 MW and 9.522%, respectively. Also, as the pressure of the pumped fluid in the Kalina cycle increases from 800 to 1600 kPa, the exergy yield of the Kalina cycle and the exergy yield of the whole combined system increase to 36.34% and 44.26%, respectively. [ABSTRACT FROM AUTHOR]

Nowadays due to increasing energy demand in the world, the use of energy systems with maximum efficiency is unavoidable. Thermal integration of the systems decreases the number of equipment employed and also raises the efficiency of the hybrid configuration. In the present study, an innovative hybrid system for cogeneration of power and desalinated water including organic Rankine unit, carbon dioxide power plant, Kalina power cycle based on the seawater temperature difference, and multi-effect desalination system is developed. Part of the heat required by the system is provided by solar flat plate collectors. The innovative hybrid system produces 849.5 MW power and 198.5 kg/s potable water. Exergy investigation of the system indicates that the most exergy destruction in the whole system belongs to the combustion chamber and heat exchangers, each of which is 46.60% and 34.91% of the total exergy destruction, respectively, which shows that more than 80% of exergy destruction is related to these two parts. The exergy efficiency of the whole system is 44.81%. Through the pinch method, the heat exchanger network related to the multi-stream heat exchangers of the hybrid system is extracted. The effect of air /fuel ratio (inlet to the combustion chamber) on system performance in the parametric analysis is examined. One of the main results is a 12.69% improvement compared to the initial state of total electrical efficiency of the structure in case of increasing the fuel input to the combustion chamber up to 62.00 kg/s. By system reliability analysis and examining different modes of failure and repair rates of different sections of the system, the probability of the structure operation in different cases is extracted. [Display omitted] [ABSTRACT FROM AUTHOR]

The increasing growth of helium consumption in industries and the limited resources of this element are the challenges that industries will face in the future. One way to reduce the energy consumption in producing crude helium is to integrate it with low-temperature cycles. Also, using solar energy as a source of energy production in areas that receive adequate solar energy is an important strategy for energy supply in terms of environmental compatibility and sustainable development. In this paper, a novel integrated structure for producing liquid methanol, liquefied natural gas, and crude helium gas using the process of separating helium from natural gas, methanol synthesis process, organic Rankine cycle, and solar dish collectors is developed and analyzed. This hybrid system produces 3590 kmol h−1 liquid methanol, 3590 kmol h−1 liquefied natural gas, and 18.91 kmol h−1 crude helium. The feed gas extracted from the process of separating helium from natural gas is fed to the steam-natural gas reforming unit, which produces syngas with an amount of 16,015 kmol h−1. To supply the input heat to the reforming, solar dish collectors with the climatic conditions of Tehran in Iran are used. The produced syngas along with carbon dioxide is fed into the methanol synthesis unit. The energy and exergy efficiencies of the developed integrated structure are 88.48% and 93.79%, respectively. The exergy analysis of the integrated structure shows that the maximum exergy destruction corresponds to the heat exchangers (56.23%) and reactors (13.83%). The sensitivity analysis illustrates that with an increase in the outlet flow temperature of the methanol reactor from 100 to 200 °C, the energy and exergy efficiencies are increased by 9.939% and 9.257%, respectively. Besides, by increasing the amount of carbon dioxide feeding to the methanol production process from 100 to 1200 kmol h−1, the net power consumed and its thermal efficiency are increased by 8.489% and 2.855%, respectively. [ABSTRACT FROM AUTHOR]

Summary: In this study, a novel integrated structure for generation of the oxygen, hydrogen, power, and hot water by employing thermochemical reactors and solar dish collectors is proposed. The presented process including solar dish collectors, sulfur‐iodine thermochemical cycle, and Organic Rankine Cycle. In this configuration, for 5854 kmol/h of inlet water, 2236 kmol/h of oxygen, and 4432 kmol/h of hydrogen are produced. This system can provide 22 666 kW of power that 22 026 kW is utilized in the sulfur‐iodine reaction. So, the net electrical power is found to be 640 kW. A general exergy analysis is carried out on the whole structure and equipment to find its exergy losses and improvement potential to enhance the exergy efficiency of the system. The total exergy efficiency of the process is calculated 56.33% and its exergy destruction is obtained 382 301.31 kW. Heat exchangers and solar collectors have the highest values of destructed exergy, which about 69% of destructed exergy is related to them. These devices have a strong potential for enhancement. The results showed that component P1 (pump) has the lowest exergy efficiency that is 15.58%, while its exergy destruction is not the greatest. Therefore, for having a better examination of this structure, both exergy efficiency and exergy destruction parameters should be evaluated simultaneously. Moreover, a sensitivity analysis is applied to survey the performance of some performance indicators vs different design parameters. It is concluded that by an increase in generated heat by solar collectors, exergy efficiency, energy efficiency, oxygen, and hydrogen production faces increment. [ABSTRACT FROM AUTHOR]

In order to solve the water and energy crisis problem, the thermal water desalination and parabolic trough solar collectors are used at the cogeneration plants. In this paper, an integrated structure for cogeneration of fresh water and power has been developed using a multi-stage thermal water desalination system and organic Rankine cycle. In order to supply the input heat, an integrated structure of parabolic trough solar collectors, and to supply the condenser cooling of organic Rankine cycle, the re-gasification operations have been used. This integrated structure is capable of fresh water generation of 3628 kgmol/h and electrical power of 459.9 MW. In this integrated structure, the efficiency of the organic Rankine cycle power plant and gain output ratio of the multi effect desalination system is 12.47% and 2.918, respectively. Exergy analysis has been used to examine the second law of thermodynamics and the quality of the integrated structure. The total exergy efficiency of the integrated structure is 87.11%, and also, the highest share of equipment exergy destruction is related to the heat exchangers and collectors by 50.23% and 38.18%, respectively. In order to simulate the dynamics of the integrated structure, according to the input climatic information of the studied location in Tehran, Iran. Furthermore, decisions are made upon the sensitivity analysis on economic important indicators within an integrated structure. • Multi effect desalination and organic Rankine cycle hybrid system are introduced. • Parabolic trough solar collectors produced heat is used as a heat source of the ORC & MED. • Re-gasification operation is used as a cooling source of the organic Rankine cycle. • To simulate this integrated structure, the HYSYS, TRNSYS & MATLAB software are used. • Exergy, sensitivity & economic analysis of the integrated system are conducted. [ABSTRACT FROM AUTHOR]

A novel structure for hydrogen liquefaction is developed and thermodynamically analyzed. The modified structure, which produces approximately 290 tons of liquid hydrogen (L H 2) per day, consists of a basic hydrogen liquefier system, an organic Rankine cycle, an absorption refrigeration system, and solar parabolic dishes. The new approach of simultaneous considering of exergy destruction rate and exergy efficiency is used to analyze the system, which results in lower energy consumption and higher exergy efficiency. Accordingly, the COP of the plant is calculated as 0.2002 and it consumes 4.02 k W h / k g L H 2 that is 8.93 percent less than the basic liquefier. Moreover, the overall exergy efficiency of it is 73.57% is 24.60% more than the basic system one. As well as, results indicate that the cryogenic sector of the process consumes 73% of the total consumed energy. Furthermore, exergy analysis shows that the most exergy destruction occurs in the solar collectors (43.59%) and heat exchangers (40.23%), and when the exergy efficiency varies 1.9% during a typical day, the exergy destruction change will be 9.5%. As well as, sensitive analysis shows that when solar energy increases by 204% due to adding more solar collectors, boilers energy decreases by 59%. Moreover, when the number of the collectors doubles, the production rates and the energy consumption of the process are also doubled. However, more power will be needed that will increase the operating cost of the liquefier. Therefore, an exergy-economy analysis may be used to address the optimum solutions. [ABSTRACT FROM AUTHOR]

The simultaneous design of units and the integration of processes reduce the amount of required equipment and energy consumption. Types of research in recent years have turned their attention to improving the efficiency of thermal and heat recovery systems. This paper aims to develop an integrated structure for simultaneous generation of power and liquefaction of carbon dioxide. The hybrid system consists of four sections: oxy - fuel power plant for power generation with CO 2 capture, pure oxygen production using the air separation unit, carbon dioxide liquefaction system using an absorption refrigeration cycle and heat supply using solar dish collectors. The integrated design has the capacity of producing 26.27 kg/s of liquid carbon dioxide and 179 MW of power. Exergy analysis shows that the maximum exergy destruction belongs to the distillation towers at 24.73%, and the minimum exergy destruction is for air coolers at 0.113% compared to other equipment. Accordingly, the total exergy efficiency of the whole integrated structure is 60.74% and the total exergy destruction is 416 MW. The economic analysis of the integrated structure shows that the period of return is 3.3 years, and the prime cost of the product is 3.04 cents/kWh. Furthermore, by using sensitivity analysis the important and effective parameters of the developed integrated structure was investigated. • Air separation unit, oxy-fuel power generation and CO 2 capture with solar dish collector hybrid system are introduced. • Solar dish collectors produced heat is used as heat source of absorption refrigeration, steam power cycle and ORC power generation. • Total energy and exergy efficiencies of the hybrid system are 37.1% and 60.74%. • Rate and period of investment return were obtained 30.33% and 3.3 years respectively. [ABSTRACT FROM AUTHOR]

• Photovoltaic thermal collectors, ejector refrigeration cycle and phase change material hybrid system are introduced. • Photovoltaic thermal collectors produced heat is used as heat source of the ejector refrigeration cycle. • Total energy and total exergy efficiencies of the hybrid system are 50.84% and 60.51%. • The rate and period of investment return were obtained 29.36% and 3.405 years, respectively. In this study, an integrated system which including photovoltaic-thermal collectors, ejector refrigeration cycle and phase change material storage is developed and analyzed. The electrical power and refrigeration energy of the proposed system are about of 6666 kW and 5395 kW, respectively. The phase-change material storage sub-system consists of capric acid-lauric acid that in the absence of heat source of solar energy at night, 5395 kW refrigeration is released to cool at a temperature of 9 °C. The energy and exergy analyses are conducted and the obtained results show that overall thermal and total exergy efficiencies are about of 60.51% and 50.84%, respectively. The sensitivity analysis is performed to investigate the effect of the important operating parameters on the system performance. In this regard, Output temperature, generated heat energy and area of the photovoltaic thermal collectors; solar radiation, produced refrigeration and volume of thermal energy storage are selected. Also, the economic analysis is conducted and the obtained results indicate that the proposed system has an investment return period of 3.405 years and a prime cost of product of 20.45 US$ per ton of refrigeration. [ABSTRACT FROM AUTHOR]

Highlights • Biogas upgrading was integrated with FPC & Kalina cycle and exergetically assessed. • The analysis was based on the real solar data for Bushehr city. • Sensitivity analysis of the integrated system was conducted. • The proposed system was able to produce upgraded biogas with a rate of 2293 kg/h. • Exergy efficiency of cycle was 92.36% & FPCs had the highest exergy destruction. Abstract The goal of this study is to develop and introduce a novel integrated system composed of water scrubbing biogas upgrading process with water regeneration, flat plate solar collectors (FPC) and Kalina power cycle. Solar thermal energy was exploited by means of FPCs and delivered to the Kalina cycle aiming at producing the electrical power required by biogas upgrading process. The excess heat in biogas upgrading cycle was recovered and fed to the Kalina cycle. The proposed system was simulated by Aspen Hysys based on the real solar data for Bushehr city. Overall, the FPCs provided 2627 kW thermal power to the Kalina cycle, where 289.5 kW electrical power was produced and delivered to the biogas upgrading process. The water scrubbing process was capable of removing the CO 2 and H 2 S contents and provided upgraded biogas with a mass flow of 2293 kg h−1. A comprehensive second law based thermodynamic analysis was accomplished to assess the effectiveness of the proposed cycle and the exergetic performance of the components was scrutinized and discussed thoroughly. The exergy efficiency of the proposed integrated system was found 92.36%. The highest exergy destruction was occurred in the FPCs being responsible for 73% of the whole exergy destruction. The desorption column and steam turbine had the second and third highest exergy destruction, respectively. The effects of collector's number and minimum approach temperature on the exergy efficiency, upgraded biogas production, Kalina cycle efficiency, and exergy destruction were studied and discussed as well. [ABSTRACT FROM AUTHOR]

In this paper, an integrated structure of cogeneration and freshwater production for residential complexes usage in an industrial town of Assaluyeh, in south of Iran and besides to the Persian Gulf is developed and analyzed. In this process, solar flat plate collectors on the house's roof to provide the required thermal energy, Kalina cycle to generate integrated power and a multi-stage desalination process for the freshwater production of residential complexes, are utilized. The proposed system is simulated through TRNSYS, HYSYS, and MATLAB Software. This integrated structure has the capability of simultaneous production of 1869 kW power, 65194 kW heating and 83.22 kg/s freshwater for residential complexes. Based on the results the integrated structure has a total thermal efficiency of 44.64% and a total exergy efficiency of 90.04%. Exergy analysis shows that the highest amount of exergy destruction on a specific day of the year, the percentage of the destructed exergy from the input exergy flow, occurs in the solar flat collectors and the auxiliary boiler, 54.72%, 21.89%, respectively. By sensitivity analysis of the important indices for the developed integrated structure, including the number of collectors, the mass flow rate of the collector and the molar composition of the Kalina power generation cycle, an appropriate solution is proposed to improve the modeling effective parameters. [ABSTRACT FROM AUTHOR]

In this paper, a novel process is developed to cogenerate 4741 kg/h of methanol, 297.7 kW of electricity, and 35.73 ton/h of hot water, including a hydrogen purification system, an absorption–compression refrigeration cycle (ACRC), a regenerative Organic Rankine Cycle (ORC), and parabolic solar troughs. The heat produced in the methanol reactor is recovered in the ORC and ACRC. Parabolic solar troughs provide thermal power to the methanol distillation tower. Thermal efficiencies of the integrated structure and the liquid methanol production cycle are 78.14% and 60.91%, respectively. The process's total exergy efficiency and irreversibility are 89.45% and 16.89 MW. The solar thermal collectors take the largest share of exergy destruction (34%), followed by heat exchangers (30%) and mixers (19%). Based on the sensitivity analysis, D17 (mixture of H2 and low-pressure fuel gas before separation) was the most influential stream affecting the performance of the process. With the temperature decline of stream D17 from −139 to −149 °C, the methanol production rate and the total thermal efficiency rose to 4741.2 kg/h and 61.02%, respectively. Moreover, the growth in the hydrogen content from 55% to 80% molar of the feed gas, the flow rate of liquid methanol, and the total exergy efficiency declined to 4487 kg/h and 86.05%. [ABSTRACT FROM AUTHOR]

One of the most common methods of ammonia production used in the last hundred years is the Haber-Bosch process. The basis of this process is hydrogen and nitrogen, which must be supplied in different ways. In the present study, a novel integrated structure for tri-generation of liquid ammonia, carbon dioxide, and power through the Haber-Bosch process, amine-based carbon dioxide capture cycle, and absorption-compression refrigeration cycle is developed. The required nitrogen of this process is supplied by the cryogenic air separation system with the help of the liquefied natural gas regasification process and the required hydrogen is supplied through a steam methane reforming process with the help of an amine-based CO 2 capture cycle. The needed cooling by the Haber-Bosch process at − 50 °C is also provided by the absorption-compression refrigeration cycle. The required power of the whole system is generated through the organic Rankine cycle. Solar energy heat source and power plant exhaust flue gas are used to supply heat to different parts of the integrated system. Simultaneous design of units and integration of processes reduces the number of required equipment and reduces energy consumption, thus increases the system efficiency. This hybrid structure produces 3.042 kg/s ammonia as the main product, 13,300 kW power, 2.762 kg/s CO 2 , 3.929 kg/s pure oxygen, and 11.31 kg/s hot water as byproducts. The total energy and exergy efficiencies of the combined structure are 46.95% and 57.36%, respectively. Exergy investigation of the combined system illustrates that the highest rate of exergy destruction includes heat exchangers (46.18%), collectors (18.45%), and towers (14.97%) of the total exergy destruction. Sensitivity analysis is performed on the sensitive parameters of the system and its results are reported. [Display omitted] • Integrated Haber-Bosch process, steam methane reforming and air separation unit. • CO 2 capture unit were employed to hydrogen purification. • LNG regasification and solar collectors used to supply the utility of the system. • This structure produced 3.042 kg/s ammonia, 13,300 kW power and 2.762 kg/s CO 2. • Total exergy efficiency & exergy destruction of the system were 57.36% & 116,763 kW. [ABSTRACT FROM AUTHOR]

The utilization of renewable energy sources such as solar energy and biogas have recently received more attention due to a decline in fossil energy sources and environmental issues. A leading method for long-term renewable energies sources storage is to convert to fuels such as hydrogen and heavy value hydrocarbons. In this work, a novel integrated structure is developed for sustainable cogeneration of hydrogen and heavy liquid hydrocarbon fuels. This integrated structure consists of the zinc-sulfur-iodine thermochemical cycle, biogas treatment cycle, Fischer–Tropsch synthesis reactions, a carbon dioxide power generation, and solar dish collectors. It is demonstrated that this integrated structure produces 359.8 kmol/h hydrogen, 116.8 kmol/h liquid fuels, 1714 kmol/h carbon monoxide, and 289,149 kmol/h hot water. The thermal energy and exergy efficiencies of the integrated structure are 58.03% and 44.34%, respectively. The exergy analysis illustrates that exergy destruction mostly occurs in heat exchangers (36.67%), reactors (24.69%), and collectors (20.25%). The sensitivity analysis demonstrates that the absorbed useful energy and solar collector thermal efficiency decrease up to 9.735 kW and 0.7751, respectively when the average operating wall temperature in each solar collector increases from 627 °C to 1127 °C. The thermal efficiency and productivity of the liquid fuels increase up to 0.63 and 383.6 kmol/h, respectively with increase of carbon dioxide composition in the biogas from 40 mol% to 55 mol%. [Display omitted] • A novel solar energy storage system for long-term was developed, validated & assessed. • Integrated ZnSI thermochemical cycle, biogas treatment cycle and Fischer–Tropsch synthesis. • Heat generated by the GTL process and solar collectors were used to supply heat to the cycle. • Integrated structure produced 359.8 kmol/h hydrogen and 116.8 kmol/h liquid fuels. • Thermal energy and exergy efficiencies of the hybrid system were 58.03% and 44.34%. [ABSTRACT FROM AUTHOR]

Biogas upgrading is a process that increases methane content to an acceptable percentage is compared with natural gas and reduces impurities such as CO 2 and H 2 S in the biogas. Several methods for biogas upgrading are used. The selection of biogas upgrading methods depends on the type of biogas and the facilities' requirement according to local circumstances. This paper presents a study on an integrated process of cryogenic biogas upgrading by using renewable energy resources for sustainable development. Parabolic trough solar collector (PTC), organic Rankine cycle (ORC) power system and absorption refrigeration cycle are used in this process to separate the impurity of raw biogas. PTC supplies the required heat for the ORC, and absorption refrigeration cycles. Inlet biogas contains 61.10%, 36.93% and 0.01% (mole percent) CH4, CO 2 and H 2 S. After purification, upgraded biogas contains 92.67% CH4 and 4% CO 2. The results of the exergy analysis of the process show that the overall exergy efficiency of the integrated process and solar collector are 71.62% and 51.37% respectively. Also, the cryogenic heat exchangers have the highest exergy efficiency while the most exergy destruction occurs in the solar collector and afterward in the column. Sensitivity analysis on the effective parameters such as wind speed, ambient temperature, and auxiliary energy ratio is investigated. • Integrated process of cryogenic biogas upgrading is studied. • Parabolic trough solar collector, organic Rankine cycle power system are used. • Overall exergy of the process is 71.62% and solar collector exergy efficiency is gained 51.37%. [ABSTRACT FROM AUTHOR]

• An integrated system for production of methanol and power is investigated. • Hybrid solar system and high temperature energy storage system are used in the process. • Overall thermal efficiency of the charging and discharging modes are 0.8486 and 0.4076. • Overall exergy efficiency of the charging and discharging modes are 0.5711 and 0.4232. • The highest exergy destruction belongs to Reactors3 with value of 89324 kW. The utilization of solar-assisted hybrid energy systems is an appropriate way to generate green power. To this aim, an innovative hybrid charging/discharging system comprised of solar dish collectors, methanol synthesis unit, power cycles, and carbon dioxide liquefaction process as well as phase change materials, is introduced and thermodynamically assessed. An ammonia/water absorption refrigeration cycle is applied for the carbon dioxide liquefaction process. The proposed structure is simulated by using HYSYS, TRNSYS, and MATLAB, and a thermodynamics framework is conducted to assess the integrated system performance. The proposed structure successfully produces 8.449 kg/s and 11.49 kg/s of methanol liquid carbon dioxide, respectively. Energy analysis of this integrated system indicates that, the overall thermal efficiency of the charging and discharging modes are 0.8486 and 0.4076, respectively. The results of exergy evaluation reveal that the largest exergy destruction in the charging and discharging modes are related to collectors with 34.07% and reactors with 56.58%, respectively. In addition, the overall exergy efficiency of the charging and discharging cycles are 57.11% and 42.32%, respectively. A comparison between the proposed system and similar works show that the energy efficiencies of the power cycles are higher than similar studies. Finally, sensitivity analyses on the influence of various parameters such as useful energy collected by collectors, stored heat of phase change materials, solar collector thermal efficiency, irreversibility, and exergy efficiency in the cycle and collector are performed. [ABSTRACT FROM AUTHOR]

• A hybrid tri-generation system was developed, validated & assessed. • Integrated parabolic solar collectors, ORC, MED & cryogenic CO 2 capture-LNG cold. • System produced 14.5 ton/h LNG, 1.693 ton/h fresh water & 2.611 ton/h liquid CO 2. • Total exergy efficiency of the hybrid system was 88.97%. • The prime cost of product & POR were obtained 24.2 cents/kg LNG & 6 years, respectively. Global energy consumption, in various forms, is rapidly increasing, owing to population and economic growth, and as a consequence energy-related CO 2 emissions are dramatically rising. Hence, energy demand and mitigation of CO 2 emissions are in urgent need of being dealt with. In this perspective paper, a novel approach, combining a system of simultaneous power cooling and fresh water is conducted an investigation by the exergetic and thermoeconomic approaches. The conventional energy storage methods are not able to perform under long-term condition as well as the possibility of transferring it to the considered location can be exorbitant. One of the leading methods for renewable energy storage is the simultaneous generation of liquid carbon dioxide and LNG using solar energy and heat loss. This integrated structure is composed of four sub-systems: Organic Rankine cycle system for power generation using parabolic trough collectors, using a mixture of ammonia and water as a working fluid in refrigeration cycle to produce liquefied natural gas (LNG) and liquid CO 2 , carbon dioxide capture process, multiple-effect distillation desalination. This hybrid system enjoys a capacity to produce 14.5 ton/h of LNG, 1.693 ton/h of desalinated water, and 2.611 ton/h of liquid CO 2. The results of exergy analysis demonstrate that overall exergy efficiency of the process is 88.97%, and the component-based assessments also show that the highest exergy destruction is associated with towers (the average proportion of 39.23%), whilst the lowest exergy destruction ration is quantified for valves and drums (0.1352%). The economic appraisal results of the hybrid structure reveals that duration of return is 6 years, and the prime cost of the product is 24.2 cents/kg LNG. Moreover, sensitivity analysis is intended to discern the influential parameters of the developed hybrid arrangement. [ABSTRACT FROM AUTHOR]

• Developing of a trigeneration system for fresh water & LNG production using hybrid refrigeration systems. • Using solar dish collector for generating heat & power in the trigeneration system. • Reduction in CO 2 emission & natural gas consumption with the aid of solar dish collectors. • Conducting exergy, sensitivity analyses & economic evaluation for the two integrated structures. In this paper, a hybrid tri-generation system is designed to produce LNG and freshwater simultaneously based on a multi-effect desalination system and analyzed using energy and exergy analyses. For natural gas liquefaction, the initially required cooling of the cycle is supplied by ammonia-water absorption system, and the required intermediate cooling load and liquefaction process are provided by a refrigeration system with mixed fluid. Two alternatives for providing power generation to the system and the required heat for driving the absorption cycle have been considered and compared. The first alternative relies on a natural-gas-fired power plant, while the second is based on steam-solar power plant with dish collectors. The former results in the total energy efficiency of 85.8% (LHV). The highest thermodynamic irreversibilities occur in the heat exchangers (61%), even if they have the highest exergy efficiency compared to the other plant equipment. On the other hand, using solar dish collectors enables to decrease carbon dioxide emissions by 40%, and increases freshwater and LNG production by 95% and 4.7% respectively. The power obtained per kg of LNG produced is about 0.19 kWh, which is less than or equal to the other similar patents. The results of the economic analysis with the annualized cost method of the system show that the products prime cost of both structures 1 and 2 are equal to 0.2580 and 0.1784 US$ per kg of LNG, respectively. A suitable strategy for modelling enhancement of system's parameters is suggested by expanding of sensitivity analysis on the important parameters of the developed system. [ABSTRACT FROM AUTHOR]

• A novel integrated system for liquid hydrogen production is developed. • This system consists of the thermo-electrochemical and hydrogen liquefaction cycles. • Solar dish collectors are used for supplying the system required heat demand. • Pinch method on multi-stream exchangers to achieve heat exchanger networks is used. • The total thermal efficiency of the integrated system is 71.4% Hydrogen production and liquefaction using solar thermo-electrochemical water splitting systems can as an effective method for long-term renewable energy source storage are suggested. In this paper, a novel integrated configuration for the cogeneration of liquid hydrogen and oxygen by magnesium-chlorine thermo-electrochemical water splitting cycle, hydrogen liquefaction unit, and solar dish collectors is developed. The novel integrated structure produces 7116 kg/h liquid hydrogen and 57597 kg/h oxygen. Through the magnesium-chlorine cycle, pure hydrogen is produced and the required energy is supplied through solar renewable energy based on the climatic conditions of Isfahan city in Iran. Then the produced hydrogen enters the liquefaction process to generate liquid hydrogen. The heat and power consumption of the whole system for the cogeneration of liquid hydrogen and oxygen are 207.9 MW and 373.9 MW, respectively. The heat waste of the integrated structure is used to produce hot water as a by-product. The specific power consumption of the liquefaction cycle is 7.6 kWh/kg LH 2 and also the total thermal efficiency of the whole integrated system is 71.4%. Through the pinch method, heat exchanger networks related to multi-stream heat exchangers of the present system are extracted. Sensitivity analysis is used to investigate the effects of changes in major parameters including operating conditions of the thermo-electrochemical cycle as well as changes in the solar dish collector main parameters and the results are reported. [ABSTRACT FROM AUTHOR]