Recently, the use of solar thermal collectors has increased significantly. In the present work, energy, exergy, enviroeconomic and exergoeconomic analyses of various solar thermal collectors are ...investigated. These solar thermal collectors include flat-plate solar collector, linear Fresnel solar reflector, parabolic trough solar collector and solar parabolic dish collector. To examine the performance of these solar collectors two different working fluids, i.e. water and Thermia Oil B are considered. Furthermore, evaluation of the performance of solar collectors using nanofluids consisting of Al2O3 and CuO nanoparticles is presented. Also, in this paper, parameters such as exergy destruction rate, entropy generation rate, Sustainability index and Levelized Cost of Electricity for solar collectors are discussed. The performance of solar collectors in two different cities located in Iran (Tehran and Tabriz) is discussed for two different days (a winter day (2-Feb) and a summer day (14-Jun)). MATLAB software is used for mathematical modeling of solar thermal collectors. The results revealed that, the best and weakest performance from energy and energy points of view in all cases are related to the dish collector and flat-plate collector, respectively. Furthermore, the obtained results of the use of nanofluids as well as economic analysis may present new insights to the operation and development of such solar thermal systems.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the present study, a combined heat and power process consists of molten carbonate fuel cell, thermoelectric generator, linear Fresnel solar reflector and power turbine is introduced and ...investigated from energy, exergy and thermodynamic points of view. Fuel cell produces electrical and thermal power. A part of waste heat from the fuel cell is sent to the thermoelectric generator to produce additional power and the remaining enters the environment. The solar field as a heat exchanger generates a part of the required thermal power of the proposed process. Linear Fresnel solar reflector with duty of 1728 kW is used too. Numerical modeling and thermodynamic analysis of the proposed system is done using MATLAB and HYSYS softwares, respectively. The results were discussed in two scenarios: (1) investigation of fuel cell and thermoelectric generator hybrid system and (2) investigation of whole combined heat and power process. Results indicate that the overall and electrical efficiencies of the proposed system are 64.93% and 31.57%, respectively. Also, in this process, 41728.8 kW of exergy is destroyed and the process total exergy efficiency is gained 0.12%. Finally sensitivity analysis of the fuel cell, turbines, solar system and thermoelectric generator against effective parameters is investigated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Due to the high volume of wastewater produced from dairy factories, it is necessary to integrate a water recovery process with the treatment plant. Today, bipolar membrane electrodialysis units ...(BMEUs) are increasingly developed for wastewater treatment and reutilizing. This article aims to develop and evaluate (technical and cost analyses) a combined BMEU/batch reverse osmosis unit (BROU) process for the recovery of chemicals and water from the dairy wastewater plant. The combined BROU/BMEU process is able to simultaneously produce water and strong base-acid, and reduce power consumption due to the injection of concentrated feed flow into the BMEU. A comprehensive comparative analysis on the performances of two combined and stand-alone BMEU configurations are developed. The proposed combined technology for dairy factory wastewater treatment is designed on a new structure and configuration that can address superior cost analysis compared to similar technologies. Further, the optimal values of permeate flux and current density as two vital and influencing parameters on the performance of the studied dairy wastewater treatment process were calculated and discussed. From the outcomes, the total cost of production in the combined configuration has been reduced by approximately 26% compared to the stand-alone configuration. Increasing the feed concentration rate using the batch reverse osmosis process for the dairy wastewater treatment process can be an ideal solution from an economic point of view. Moreover, point (current density, feed concentration rate, total unit cost) =
can be considered as an optimal point for the economic performance of the studied wastewater treatment process.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Effective and maximum utilization of waste heat from industrial processes and fossil plants can improve thermodynamic performance and declined the environmental impacts of waste heat discharge to the ...atmosphere. Here, the multi-aspect assessment and optimization of a novel cogeneration power and cooling load cycle (CPCC) is developed. The considered cogeneration process is designed under a three-level waste heat recovery process consisting of an ORC (organic Rankine cycle) unit and an ejection-based refrigeration process. Thermodynamic performance, cost feasibility and environmental assessments of the suggested process have been comprehensively evaluated and discussed. A two-objective optimization is developed to minimize the total cost and maximize the exergy efficiency. Moreover, the comprehensive CPCC behavior is compared with a reference system (a single-level recovery/ORC process and a compression-based refrigeration process). The performance of the considered CPCC is also examined under various environmentally compatible refrigerants. The environmental analysis is based on two indicators (i.e., life cycle-climate performance and total equivalent-warming impacts). Due to the multi-level recovery of waste heat, the environmental impacts of emitting waste heat into the environment are significantly reduced. The outcomes revealed that the R1234/yf is considered as the most suitable refrigerant that can causes to optimum achievements for both systems. The exergetic performance is improved by about 10.3% compared to that reference system, while the exergy destruction and total annual cost of the CPCC, respectively, are reduced by approximately 7.4% and 21.6% compared to the reference cycle. It was also found that about 11,640 tons of carbon dioxide can be reduced by using the ejector in the refrigeration process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Due to the growing population rate and increasing social activities, the content of municipal solid waste (MSW) production is increasing. Energy production from MSW is one of the promising ways to ...dispose of waste and reduce the limitations of fossil energies. However, this technology has a relatively low efficiency due to the high volume of moisture and inert materials in MSW and the lower heating value of waste. The integration of solar thermal collectors is one of the suggested solutions to increase the temperature of inlet steam to the power generation cycle in order to improve the power plant performance. In this regards, the present study develops a comprehensive thermodynamic-conceptual and exergoeconomic investigation of the performance of a MSW-incineration (MSWI) plant integrated with a parabolic trough collector (PTC)-based solar field. Accordingly, the temperature of the steam elevates by the solar field before entering the electric power generation cycle. Additionally, the solar unit is integrated with a phase change material (PCM)-based storage system. The use of storage tank at the delivery line of PTC can improve the power plant’s reliability. A comprehensive comparison of the developed power plant with the conventional MSWI power plant is presented. In addition, the technical and economic behaviors of the considered power plant have been optimized under two different single and multi-objective optimization scenarios. The outcomes indicated that the developed power plant can provide 15.75% and 15.68% higher energetic and exergetic efficiencies compared to MSWI power plant. In addition, the rate of electric power obtained from S-MSWI power plant is almost 16.1% more compared to MSWI power plant. However, the total cost rate of MSWI plant is almost 24.13% lower compared to the developed power plant. But, the value of LCOE in the developed power plant is approximately 8.93% lower than MSWI power plant. It was also found that, the multi-objective optimization can provide better and optimal results to energy engineers and decision makers compared the single-optimization. The conceptual design of the implementation of the solar field is also developed in a specific geographical condition. Additionally, this research comes from the key technology of the National Key Laboratory of Environmental Protection.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•An innovative eco-efficient hybrid system that leverages coke plant energy.•The system achieves high energy efficiency, with competitive production costs.•Significantly reduce CO2 emission, aligning ...with global sustainability objective.•To generate of 12.72 MW of power, 0.51 kg/s of oxygen, and 0.53 kg/s of methanol.•The energy and exergy efficiencies of 46.8% and 85.13%, respectively.
This research presents a novel, eco-efficient hybrid system designed for the simultaneous production of power, oxygen, and methanol. It utilizes energy from coke plants and incorporates state-of-the-art waste heat recovery processes (WHRPs). The system effectively merges electricity and methanol production with WHRPs, improving both environmental sustainability and economic feasibility in industrial energy transformation. It consists of a fuel reforming and combustion unit, a waste heat recovery unit, a unit for hydrogen gas production through water electrolysis, and a methanol synthesis module. This configuration enables the production of 12.72 MW of electricity, 0.51 kg/s of oxygen, and 0.53 kg/s of methanol, achieving an energy productivity of 46.8 % and an exergy efficiency of 85.13 %. The economic analysis indicates competitive costs of $0.099 per kWh for electricity and $0.56 per kg for methanol. The system surpasses current technologies in thermodynamic efficiency, operational and product costs, and reduced CO2 emissions, demonstrating its potential as a sustainable and economically sound solution for industrial energy challenges. It supports global sustainability initiatives and fits within the circular economy concept.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•A hybrid system including fuel cell and thermoelectric subsystems is investigated.•Four cities of Iran with different weather conditions are chosen as the case studies.•Electrical ...efficiency of the proposed polygeneration system is 53.3%.
A new polygeneration system based on photovoltaic solar system, proton exchange membrane fuel cell and thermoelectric device is introduced. This proposed system is able to provide the electrical, thermal and cooling demand. A proton exchange membrane electrolyzer is used to supply the required fuel and oxidant for the fuel cell. Also, the required electrical power of the electrolyzer is supplied by a solar photovoltaic system. Heating and cooling demand is provided by proton exchange membrane fuel cell and thermoelectric cooler, respectively. Also, the required electrical power of the thermoelectric cooler is supplied by a thermoelectric generator, which uses waste heat recovery from fuel cell to produce electricity. To evaluate the solar system's performance, four cities in Iran (Tabriz, Esfahan, Shiraz and Bandar' Abbas) have been considered with different climatic conditions. The energetic modeling of the proposed system is done using coding in MATLAB software. The results show that, the electrical efficiency of the proposed system and fuel cell efficiency are 53.3% and 40.97%, respectively. The average number of solar module required in Tabriz, Esfahan, Shiraz and Bandar' Abbas is 62, 48, 46 and 46, respectively. Also, Shiraz has the highest average annual additional hydrogen production by the electrolyzer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Optical and thermal analysis of the most well-known solar concentrator system; parabolic trough collector (PTC) are investigated and analyzed. To evaluate performance of the PTC, four cities of ...Iran with different weather conditions are chosen as case studies. Effective parameters such as concentration ratio, incident angle correction factor, collector mass flow rate are considered. The main objective of this work is evaluation of the solar energy potential using PTC in under consideration cities with different climates. Numerical modeling of the analysis is done using MATLAB software. Simulation results shows that Shiraz, with an average annual thermal efficiency of 13.91% and annual useful energy of 2213 kWh/m2, is the best region to use solar concentrator systems. The impacts of other parameters such as fluid inlet temperature, input fluid flow rate and aperture area of the collector on the output of the system are also investigated. Finally, the effect of using nanofluids as heat transfer fluid on increasing the heat transfer is investigated.
•Optical and thermal analysis of the parabolic trough collector (PTC) is done for Iran cities.•Four cities of Iran with different weather conditions are chosen as the case studies.•Shiraz, with an annual thermal efficiency of 13.91% is the best region.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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•Electrical and overall exergy efficiencies of the power plant are 37.68%, 71.29%.•Effect fuel and oxidant flow rate, outlet turbine and control valves are analyzed.•Parabolic trough ...solar collector is used for supplying a portion the thermal load.•Molten carbonate fuel cell is used in the hybrid energy system.
In this paper, a combined heating and power plant consisting of molten carbonate fuel cell and parabolic trough solar collector with the carbon dioxide capturing process is investigated. Electrochemical model of the fuel cell and numerical modeling of the solar system is done using MATLAB software and thermodynamic model of the power plant is done by HYSYS software. In this plant, solar system is used as a heat exchanger with a capacity of 10.4 MW. The gas turbine and molten carbonate fuel cell are able to produce 640 MW and 81 MW of electrical power, respectively. The results show that, the electrical, overall and exergy efficiencies of the power plant are 37.68%, 71.29% and 45.13%, respectively. Also, total exergy destruction of the process and carbon capture ratio are 346029 kW and 91%, respectively. The impacts of other parameters such as fuel and oxidant flow rate, outlet pressure of the turbine, air compressor and control valves and capacity of the solar farm on the performance of the process are also investigated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZRSKP
A new integrated combined cooling, heating and power system which includes a solid oxide fuel cell, Stirling engine, steam turbine, linear Fresnel solar field and double effect absorption chiller is ...introduced and investigated from energy, exergy and thermodynamic viewpoints. In this process, produced electrical power by the fuel cell and steam turbines is 6971.8 kW. Stirling engine uses fuel cell waste heat and produces 656 kW power. In addition, absorption chiller is driven by waste heat of the Stirling engine and generates 2118.8 kW of cooling load. Linear Fresnel solar field produces 961.7 kW of thermal power as a heat exchanger. The results indicate that, electrical, energy and exergy efficiencies and total exergy destruction of the proposed system are 49.7%, 67.5%, 55.6% and 12560 kW, respectively. Finally, sensitivity analysis to investigate effect of the different parameters such as flow rate of inputs, outlet pressure of the components and temperature changes of the solar system on the hybrid system performance is also done.
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•An integrated SOFC, Fresnel collector and Stirling engine process is investigated.•Electrical, energy and exergy efficiencies of the system are 49.7%, 67.5%, 55.6%, respectively.•Stirling engine uses the SOFC waste heat and produces 656 kW power.•Fresnel solar field as a heat exchanger is used for supplying a portion the thermal power.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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