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Ibrahim Dincer - One of the best experts on this subject based on the ideXlab platform.
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Exergy and Energy Analyses
Exergy, 2013Co-Authors: Ibrahim Dincer, Marc A. RosenAbstract:This chapter presents theoretical and practical aspects of thermodynamics that are most relevant to energy and Exergy analyses. Exergy analysis is a thermodynamic analysis technique based on the second law of thermodynamics that provides an alternative and illuminating means of assessing and comparing processes and systems rationally and meaningfully. It yields efficiencies which provide a true measure of how nearly actual performance approaches the ideal, and identifies more clearly than energy analysis the causes and locations of thermodynamic losses. Consequently, Exergy analysis can assist in improving and optimizing designs. Increasing application and recognition of the usefulness of Exergy methods by those in industry, government, and academia have been observed in recent years. Exergy has also become increasingly used internationally. The study examines Exergy analysis methodologies and applies them to industrial systems, thermal energy storage, and environmental impact assessment. General implications of Exergy analysis results are shown and a step-by-step procedure for energy and Exergy analyses is given. Results of Exergy analyses of processes and systems have direct implications on application decisions and on research and development (R&D) directions. It is noted that application and R&D allocation decisions should not be based exclusively on the results of energy and Exergy analyses, even though these results provide useful information to assist in such decision making. Other factors must be considered such as economics, environmental impact, safety, and social and political implications.
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Exergy ANALYSIS OF RENEWABLE ENERGY SYSTEMS
Exergy, 2013Co-Authors: Ibrahim Dincer, Marc A. RosenAbstract:Exergy analysis is usually used to determine Exergy efficiencies and identify and quantify Exergy destructions so that directions for improved efficiency can be determined. This chapter presents Exergy analyses of several renewable energy systems including solar photovoltaic (PV) systems, solar ponds, wind turbines, and geothermal district heating systems and power plants. It describes solar PV systems and their components and discusses the use of Exergy analysis to assess and improve solar PV systems. Exergy methods provide a physical basis for understanding, refining, and predicting the variations in solar PV behavior. The study also provides and compares energy- and Exergy-based solar PV efficiency definitions. It presents a thermodynamic analysis of wind energy using energy and Exergy analysis and the Exergy is formulated of wind energy and its components. Energy and Exergy efficiencies are compared and shown to depend on the area considered. A spatio-temporal mapping approach to wind Exergy analysis is also provided. Finally, the chapter presents two case studies: energy and Exergy analyses of a geothermal district heating system and Exergy analysis of a dual-level binary geothermal power plant. These and other renewable energy systems are likely to play increasingly important roles in societies in the future.
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Performance evaluations of a geothermal power plant
Applied Thermal Engineering, 2011Co-Authors: C. Coskun, Zuhal Oktay, Ibrahim DincerAbstract:Abstract Thermodynamic analysis of an operational 7.5 MWe binary geothermal power plant in Tuzla-Turkey is performed, through energy and Exergy, using actual plant data to assess its energetic and exergetic performances. Eight performance-related parameters, namely total Exergy destruction ratio, component Exergy destruction ratio, dimensionless Exergy destruction, energetic renewability ratio, exergetic renewability ratio, energetic reinjection ratio, exergetic reinjection ratio and improvement potential are investigated. Energy and Exergy losses/destructions for the plant and its units are determined and illustrated using energy and Exergy flow diagrams. The largest energy and Exergy losses occur in brine reinjection unit. The variation of the plant energy efficiency is found between 6% and 12%. Exergy efficiency values change between 35 and 49%. The annual average energy and Exergy efficiencies are found as 9.47% and 45.2%, respectively.
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Exergy Analysis of Green Energy Systems
Green Energy, 2011Co-Authors: Ibrahim Dincer, Marc A. RosenAbstract:Exergy analysis is a thermodynamic analysis technique based primarily on the Second Law of Thermodynamics. As an alternative to energy analysis, Exergy analysis provides an illuminating means of assessing and comparing processes and systems rationally and meaningfully. Consequently, Exergy analysis can assist in improving and optimizing designs. Two key features of Exergy analysis are (1) it yields efficiencies which provide a true measure of how nearly actual performance approaches the ideal, and (2) it identifies more clearly than energy analysis the types, causes and locations of thermodynamic losses.
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Exergy energy environment and sustainable development
2007Co-Authors: Ibrahim Dincer, Marc A. RosenAbstract:This book deals with Exergy and its applications to various energy systems and applications as a potential tool for design, analysis and optimization, and its role in minimizing and/or eliminating environmental impacts and providing sustainable development. In this regard, several key topics ranging from the basics of the thermodynamic concepts to advanced Exergy analysis techniques in a wide range of applications are covered as outlined in the contents. It provides comprehensive coverage of Exergy and its applications. It connects Exergy with three essential areas in terms of energy, environment and sustainable development. It presents the most up-to-date information in the area with recent developments. It provides a number of illustrative examples, practical applications, and case studies. It features an easy to follow style, starting from the basics to the advanced systems.
I. Al-zaharnah - One of the best experts on this subject based on the ideXlab platform.
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Analysis of sectoral energy and Exergy use of Saudi Arabia
International Journal of Energy Research, 2004Co-Authors: Ibrahim Dincer, M M Hussain, I. Al-zaharnahAbstract:This paper presents the analysis of sectoral energy and Exergy utilization of Saudi Arabia by considering the energy and Exergy flows for the 12 years between 1990 and 2001. Sectoral energy and Exergy efficiencies are obtained for the subsectors and the devices used in each sector. Energy and Exergy flow diagrams for Saudi Arabia are also presented, respectively, to illustrate the situation on how energy and Exergy efficiencies vary in each sector. The residential sector appears to be the most energy efficient sector, and the industrial sector to be the most Exergy efficient. It is believed that the current methodology is useful for analyzing sectoral energy and Exergy utilization, which will help Saudi Arabia with energy savings through energy efficiency and/or energy conservation measures. It is also be helpful to establish standards to facilitate application in various sectors and processes for a sustainable energy planning. Copyright © 2004 John Wiley & Sons, Ltd.
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Energy and Exergy utilization in transportation sector of Saudi Arabia
Applied Thermal Engineering, 2004Co-Authors: Ibrahim Dincer, M M Hussain, I. Al-zaharnahAbstract:Abstract In this paper we present an analysis of energy and Exergy utilization in the transportation sector of Saudi Arabia by considering the sectoral energy and Exergy flows for the years of 1990–2001. Energy and Exergy analyses are conducted for its three subsectors, namely road, air and marine, and hence the energy and Exergy efficiencies are obtained for comparison. Road subsector appears to be the most efficient one compared to air and marine subsectors. It is found that the energy efficiencies in air and marine subsectors are found to be equal to the corresponding Exergy efficiencies due to the values of Exergy grade function. A comparison of the overall energy and Exergy efficiencies of Saudi Arabian transportation sector with the Turkish transportation sector is also presented for the year 1993 based on the data available. Although the sectoral coverage is not same for both countries, it is still useful to illustrate the situation on how subsectoral energy and Exergy efficiencies vary over the years. Turkish transportation sector appears to be a bit more efficient for that particular year. It is believed that the present technique is practical and useful for analyzing sectoral energy and Exergy utilization to determine how efficient energy and Exergy are used in transportation sector. It is also be helpful to establish standards, based on Exergy, to facilitate applications in industry and in other planning processes such as energy planning.
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Energy and Exergy use in public and private sector of Saudi Arabia
Energy Policy, 2004Co-Authors: Ibrahim Dincer, M M Hussain, I. Al-zaharnahAbstract:In this paper, we deal with the analysis of energy and Exergy utilization in the public and private sector of Saudi Arabia by considering the energy and Exergy flows for the years between 1990 and 2001. Energy and Exergy analyses for the public and private sector are undertaken to study the energy and Exergy efficiencies. These sectoral efficiencies are then compared, and energy and Exergy flow diagrams for the public and private sector over the years are presented, respectively. Energy and Exergy efficiencies of the public and private sector are compared for its six sub-sectors, namely commercial, governmental, streets, Mosques, hospitals and charity associations, particularly illustrated for the year 2000. Hospital sub-sector appears to be the most energy efficient sector and government sub-sector the most Exergy efficient one. The results presented here provide insights into the sectoral energy use that may assist energy policy makers for the country. It is believed that the present techniques are useful for analyzing sectoral energy and Exergy utilization, and that they provide Saudi Arabia with energy savings through energy efficiency and/or energy conservation measures. It is also be helpful to establish standards to facilitate application in industry and in other planning processes such as energy planning.
Shoaib Khanmohammadi - One of the best experts on this subject based on the ideXlab platform.
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Waste heat recovery in an intercooled gas turbine system: Exergo-economic analysis, triple objective optimization, and optimum state selection
Journal of Cleaner Production, 2021Co-Authors: Farayi Musharavati, Shoaib Khanmohammadi, Amirhossein PaksereshtAbstract:Abstract The development of heat and power generation systems has a major step towards sustainable development, reducing fossil energy consumption and reducing environmental pollution. Integrated energy systems are considered widely due to their high efficiency. In the present paper, an intercooled gas turbine system is developed to achieve a system with high thermal efficiency as well as better economic performance and cleaner production. The main goals of the suggested system is improvement of thermodynamic and exergo-economic performance beside multi-criteria optimization, which lead to improve the system sustainability. The intercooled gas turbine in the current work integrated with hot water system and thermoelectric generator unit to develop an advanced combined heat and power system. A comprehensive energy, Exergy, and exergo-economic analyses are employed to price assessment of the new introduced system. A comparative analysis with conventional intercooled gas turbine system is presented. The results of thermodynamic modeling indicate that an improvement about 613.3 kW, 8.21 kW, and 12.3 kW can be obtained in the gas turbine, Kalina cycle, and regenerative organic Rankine cycle subsystems. The results of energy and Exergy analysis show that the values of both energy and Exergy efficiencies for all subsystems experience increment in the new introduced. Parametric analysis based on thermodynamic and exergo-economic criteria is done and a triple objective optimization conducted to determine the best system configurations. The Technique for Order of Preference by Similarity to Ideal Solution is employed to choose the final optimal state of the system. The result of optimum selection among non-dominant solutions suggested by Pareto points indicates that the energy efficiency, total Exergy destruction rate and electricity cost rate are 53.91%, 2392.01 kW, and 52.29 $/h.
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Comparative analysis and multi-criteria optimization of a supercritical recompression CO_2 Brayton cycle integrated with thermoelectric modules
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Farayi Musharavati, Shoaib Khanmohammadi, Amirhossein PaksereshtAbstract:Regarding the high expense of the exploiting energy from energy resources, each innovation or modification on the energy systems with the aim of enhancing the efficiency and affordability is so valuable. Along with this fact, in the present work, the effects of employing thermoelectric (TEG) unit in a recompression Brayton cycle ( $${\text{sCO}}_{2}$$ sCO 2 -reB/TEG) are examined. The results of thermodynamic modeling represents that adding the thermoelectric to the system in the s $${\text{CO}}_{2}$$ CO 2 -reB can improve the net output power about 2.41 kW and increase the first and second law efficiency of s $${\text{CO}}_{2}$$ CO 2 -reB/TEG system about 1.09% and 1.12% in comparison with s $${\text{CO}}_{2}$$ CO 2 -reB system. Additionally the exergo-economic analysis for s $${\text{CO}}_{2}$$ CO 2 -reB/TEG revealed that the reactor and turbine II should be considered more than other elements from exergo-economic point of view since the highest values of $$\dot{Z}_{\rm k} + \dot{C}_{\rm D,k}$$ Z ˙ k + C ˙ D , k belong to these components. After identifying the important parameters as well as evaluating system from thermodynamic and economic aspects, a multi-objective optimization is implemented on the $${\text{sCO}}_{2}$$ sCO 2 -reB-TEG system for determining the optimum conditions. Two optimization scenarios are defined using the results of parametric analysis. Multi-objective optimization with first scenario results in total cost rate of 1.6 $ h^−1 and total Exergy efficiency of 0.5 in minimum temperature, maximum temperature and compression ratio of 36.17 °C, 577.15 °C and 1.6. Furthermore, for optimization based on second scenario results in total Exergy destruction cost and Exergy destruction rate of 3.04 $ h^−1 and 435.85 kW in 48.75 °C, 569.77 °C and 3.44 for minimum temperature, maximum temperature and compression ratio.
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Comparative analysis and multi-criteria optimization of a supercritical recompression CO_2 Brayton cycle integrated with thermoelectric modules
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Farayi Musharavati, Shoaib Khanmohammadi, Amirhossein PaksereshtAbstract:Regarding the high expense of the exploiting energy from energy resources, each innovation or modification on the energy systems with the aim of enhancing the efficiency and affordability is so valuable. Along with this fact, in the present work, the effects of employing thermoelectric (TEG) unit in a recompression Brayton cycle ( $${\text{sCO}}_{2}$$ sCO 2 -reB/TEG) are examined. The results of thermodynamic modeling represents that adding the thermoelectric to the system in the s $${\text{CO}}_{2}$$ CO 2 -reB can improve the net output power about 2.41 kW and increase the first and second law efficiency of s $${\text{CO}}_{2}$$ CO 2 -reB/TEG system about 1.09% and 1.12% in comparison with s $${\text{CO}}_{2}$$ CO 2 -reB system. Additionally the exergo-economic analysis for s $${\text{CO}}_{2}$$ CO 2 -reB/TEG revealed that the reactor and turbine II should be considered more than other elements from exergo-economic point of view since the highest values of $$\dot{Z}_{\rm k} + \dot{C}_{\rm D,k}$$ Z ˙ k + C ˙ D , k belong to these components. After identifying the important parameters as well as evaluating system from thermodynamic and economic aspects, a multi-objective optimization is implemented on the $${\text{sCO}}_{2}$$ sCO 2 -reB-TEG system for determining the optimum conditions. Two optimization scenarios are defined using the results of parametric analysis. Multi-objective optimization with first scenario results in total cost rate of 1.6 $ h^−1 and total Exergy efficiency of 0.5 in minimum temperature, maximum temperature and compression ratio of 36.17 °C, 577.15 °C and 1.6. Furthermore, for optimization based on second scenario results in total Exergy destruction cost and Exergy destruction rate of 3.04 $ h^−1 and 435.85 kW in 48.75 °C, 569.77 °C and 3.44 for minimum temperature, maximum temperature and compression ratio.
M M Hussain - One of the best experts on this subject based on the ideXlab platform.
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energy and Exergy utilization in agricultural sector of saudi arabia
Energy Policy, 2005Co-Authors: Ibrahim Dincer, M M Hussain, I AlzaharnahAbstract:Abstract This paper presents an analysis of energy and Exergy utilization in the agricultural sector of Saudi Arabia by considering the sectoral energy and Exergy flows for a period of 12 years between 1990 and 2001. Energy and Exergy analyses are conducted for its two essential devices, namely tractors and pumps, and hence the sectoral energy and Exergy efficiencies are obtained for comparison for a period of 12 years. Two main energy sources are diesel for tractors and electricity for pumps in the sector. It is found that the overall Exergy efficiencies in this sector are slightly less than the corresponding energy efficiencies, e.g. 74.19–69.20% for Exergy efficiency and 74.94–74.60% for energy efficiency from 1990 to 2001. The present technique is proposed as a useful tool in sectoral analysis of energy and Exergy utilization, developing energy policies and providing energy conservation measures.
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Analysis of sectoral energy and Exergy use of Saudi Arabia
International Journal of Energy Research, 2004Co-Authors: Ibrahim Dincer, M M Hussain, I. Al-zaharnahAbstract:This paper presents the analysis of sectoral energy and Exergy utilization of Saudi Arabia by considering the energy and Exergy flows for the 12 years between 1990 and 2001. Sectoral energy and Exergy efficiencies are obtained for the subsectors and the devices used in each sector. Energy and Exergy flow diagrams for Saudi Arabia are also presented, respectively, to illustrate the situation on how energy and Exergy efficiencies vary in each sector. The residential sector appears to be the most energy efficient sector, and the industrial sector to be the most Exergy efficient. It is believed that the current methodology is useful for analyzing sectoral energy and Exergy utilization, which will help Saudi Arabia with energy savings through energy efficiency and/or energy conservation measures. It is also be helpful to establish standards to facilitate application in various sectors and processes for a sustainable energy planning. Copyright © 2004 John Wiley & Sons, Ltd.
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Energy and Exergy utilization in transportation sector of Saudi Arabia
Applied Thermal Engineering, 2004Co-Authors: Ibrahim Dincer, M M Hussain, I. Al-zaharnahAbstract:Abstract In this paper we present an analysis of energy and Exergy utilization in the transportation sector of Saudi Arabia by considering the sectoral energy and Exergy flows for the years of 1990–2001. Energy and Exergy analyses are conducted for its three subsectors, namely road, air and marine, and hence the energy and Exergy efficiencies are obtained for comparison. Road subsector appears to be the most efficient one compared to air and marine subsectors. It is found that the energy efficiencies in air and marine subsectors are found to be equal to the corresponding Exergy efficiencies due to the values of Exergy grade function. A comparison of the overall energy and Exergy efficiencies of Saudi Arabian transportation sector with the Turkish transportation sector is also presented for the year 1993 based on the data available. Although the sectoral coverage is not same for both countries, it is still useful to illustrate the situation on how subsectoral energy and Exergy efficiencies vary over the years. Turkish transportation sector appears to be a bit more efficient for that particular year. It is believed that the present technique is practical and useful for analyzing sectoral energy and Exergy utilization to determine how efficient energy and Exergy are used in transportation sector. It is also be helpful to establish standards, based on Exergy, to facilitate applications in industry and in other planning processes such as energy planning.
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Energy and Exergy use in public and private sector of Saudi Arabia
Energy Policy, 2004Co-Authors: Ibrahim Dincer, M M Hussain, I. Al-zaharnahAbstract:In this paper, we deal with the analysis of energy and Exergy utilization in the public and private sector of Saudi Arabia by considering the energy and Exergy flows for the years between 1990 and 2001. Energy and Exergy analyses for the public and private sector are undertaken to study the energy and Exergy efficiencies. These sectoral efficiencies are then compared, and energy and Exergy flow diagrams for the public and private sector over the years are presented, respectively. Energy and Exergy efficiencies of the public and private sector are compared for its six sub-sectors, namely commercial, governmental, streets, Mosques, hospitals and charity associations, particularly illustrated for the year 2000. Hospital sub-sector appears to be the most energy efficient sector and government sub-sector the most Exergy efficient one. The results presented here provide insights into the sectoral energy use that may assist energy policy makers for the country. It is believed that the present techniques are useful for analyzing sectoral energy and Exergy utilization, and that they provide Saudi Arabia with energy savings through energy efficiency and/or energy conservation measures. It is also be helpful to establish standards to facilitate application in industry and in other planning processes such as energy planning.
Marc A. Rosen - One of the best experts on this subject based on the ideXlab platform.
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selection of optimum working fluid for organic rankine cycles by Exergy and Exergy economic analyses
Sustainability, 2015Co-Authors: Kamyar Darvish, M A Ehyaei, Farideh Atabi, Marc A. RosenAbstract:The thermodynamic performance of a regenerative organic Rankine cycle that utilizes low temperature heat sources to facilitate the selection of proper organic working fluids is simulated. Thermodynamic models are used to investigate thermodynamic parameters such as output power, and energy efficiency of the ORC (Organic Rankine Cycle). In addition, the cost rate of electricity is examined with exergo-economic analysis. Nine working fluids are considered as part of the investigation to assess which yields the highest output power and Exergy efficiency, within system constraints. Exergy efficiency and cost rate of electricity are used as objective functions for system optimization, and each fluid is assessed in terms of the optimal operating condition. The degree of superheat and the pressure ratio are independent variables in the optimization. R134a and iso-butane are found to exhibit the highest energy and Exergy efficiencies, while they have output powers in between the systems using other working fluids. For a source temperature was equal to 120 °C, the Exergy efficiencies for the systems using R134a and iso-butane are observed to be 19.6% and 20.3%, respectively. The largest Exergy destructions occur in the boiler and the expander. The electricity cost rates for the system vary from 0.08 USD/kWh to 0.12 USD/kWh, depending on the fuel input cost, for the system using R134a as a working fluid.
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Exergy analysis of thermal energy storage in a district energy application
Renewable Energy, 2015Co-Authors: Behnaz Rezaie, Bale V. Reddy, Marc A. RosenAbstract:The role of thermal energy storage (TES) in district energy (DE) system is assessed. The Friedrichshafen DE system is considered as a case study and Exergy analysis is utilized. The TES is designed to complement and to increase the effectiveness of the solar panels included in the district energy system. The TES stores the surplus solar energy until is needed by thermal energy users of the Friedrichshafen DE system. The results quantify the positive impact of the TES on the performance of the Friedrichshafen DE system, and demonstrate that the overall energy and Exergy efficiencies of the TES are 60% and 19%, respectively. It is also shown over an annual period that the temperature, energy, Exergy and energy efficiency of the TES exhibit similar trends and that the TES Exergy accumulation and Exergy efficiency exhibit similar trends.
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Exergy ANALYSIS OF RENEWABLE ENERGY SYSTEMS
Exergy, 2013Co-Authors: Ibrahim Dincer, Marc A. RosenAbstract:Exergy analysis is usually used to determine Exergy efficiencies and identify and quantify Exergy destructions so that directions for improved efficiency can be determined. This chapter presents Exergy analyses of several renewable energy systems including solar photovoltaic (PV) systems, solar ponds, wind turbines, and geothermal district heating systems and power plants. It describes solar PV systems and their components and discusses the use of Exergy analysis to assess and improve solar PV systems. Exergy methods provide a physical basis for understanding, refining, and predicting the variations in solar PV behavior. The study also provides and compares energy- and Exergy-based solar PV efficiency definitions. It presents a thermodynamic analysis of wind energy using energy and Exergy analysis and the Exergy is formulated of wind energy and its components. Energy and Exergy efficiencies are compared and shown to depend on the area considered. A spatio-temporal mapping approach to wind Exergy analysis is also provided. Finally, the chapter presents two case studies: energy and Exergy analyses of a geothermal district heating system and Exergy analysis of a dual-level binary geothermal power plant. These and other renewable energy systems are likely to play increasingly important roles in societies in the future.
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Exergy and Energy Analyses
Exergy, 2013Co-Authors: Ibrahim Dincer, Marc A. RosenAbstract:This chapter presents theoretical and practical aspects of thermodynamics that are most relevant to energy and Exergy analyses. Exergy analysis is a thermodynamic analysis technique based on the second law of thermodynamics that provides an alternative and illuminating means of assessing and comparing processes and systems rationally and meaningfully. It yields efficiencies which provide a true measure of how nearly actual performance approaches the ideal, and identifies more clearly than energy analysis the causes and locations of thermodynamic losses. Consequently, Exergy analysis can assist in improving and optimizing designs. Increasing application and recognition of the usefulness of Exergy methods by those in industry, government, and academia have been observed in recent years. Exergy has also become increasingly used internationally. The study examines Exergy analysis methodologies and applies them to industrial systems, thermal energy storage, and environmental impact assessment. General implications of Exergy analysis results are shown and a step-by-step procedure for energy and Exergy analyses is given. Results of Exergy analyses of processes and systems have direct implications on application decisions and on research and development (R&D) directions. It is noted that application and R&D allocation decisions should not be based exclusively on the results of energy and Exergy analyses, even though these results provide useful information to assist in such decision making. Other factors must be considered such as economics, environmental impact, safety, and social and political implications.
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closed and open thermochemical energy storage energy and Exergy based comparisons
Energy, 2012Co-Authors: Ali Haji Abedin, Marc A. RosenAbstract:TES (Thermal energy storage) can enhance energy systems by reducing environmental impact and increasing efficiency. Thermochemical TES is a promising new type of TES, which permits more compactness storage through greater energy storage densities. In this article, closed and open thermochemical TES is investigated using energy and Exergy methods. The latter method enhances assessments of made using the former. Efficiencies based on energy and Exergy are determined for the overall storage cycle and its charging, storing and discharging processes. Examples using experimental data are presented to illustrate the analyses of closed and open thermochemical TES. The overall system energy and Exergy efficiencies, respectively, are determined to be 50% and 9% for the closed storage, and 69% and 23% for the open storage. The results suggest that there is a significant margin for loss reduction and efficiency improvement for closed and open thermochemical storages, since the Exergy efficiencies of both are significantly lower than the energy efficiencies.