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The main objectives of this study are to perform a dynamic thermo-ecological cost (TEC) assessment and performance analyses of a multi generation system using the TRNSYS 18 software package for comparison purposes. The system has five outputs consisting of electricity, clean water, heating, hydrogen, and cooling. Multigeneration is made of an internal combustion engine fueled by natural gas, a heat pump, a reverse osmosis desalination plant and a magnesium-chlorine (Mg–Cl) thermochemical (TC) water splitting cycle. This cycle, which appears to be a promising TC hydrogen production method, is integrated to the multi generation system for producing hydrogen for waste heat recovery. Environmental effect of the system is also considered using the TEC method. In this contribution, a new index, namely the TEC of the irreversibility, is presented and applied. Variation of emissions, electricity, exergy destruction and energy loss values for the considered system and Mg–Cl TC water splitting cycle as well as TECs of the electricity, heat and the hydrogen are calculated through some parametric studies undertaken and presented in figures. It is determined that the multigeneration system has an energy efficiency value of 0.43 and a corresponding exergy efficiency of 0.38. As a result, TECEL, TECHEAT and T E C H 2 values of the considered system are obtained to be 2.98, 0.72 and 2.90, respectively. It may be concluded that the TEC is an effective method to assess the environmental performance of various energy systems and compare them with each other.

This study aims to evaluate the sustainable energy performance of 36 OECD (Organization for Economic Cooperation and Development) countries. The sustainable energy performance evaluation of the cou...

"Early Access" This paper targets to consider a hybrid cycle consisting of a solid oxide fuel cell and an Ericsson thermal engine that provides drinking water by connecting to a reverse osmosis desalination unit. First, a parametric assessment was performed on the target functions, including power, exergy destruction density, and fresh water production. After conducting studies on the composition of these target functions, three scenarios are defned for the simultaneous optimization of the mentioned functions. The frst scenario targets to optimize the exergy destruction density (Exd) and the fresh water production (mf ). In this scenario the exergy destruction and fresh water production have a better condition in the FUZZY approach, that the maximum value of the exergy destruction density and fresh water production are 450.879 (W m−2) and 2.078 (kg s −1), respectively. The second scenario attempts to optimize the power (P) and the fresh water production (mf ). According this scenario the power has the highest value in the FUZZY that is equal to 531.965 (KW), besides the fresh water production achieves to a maximum value in TOPSIS which it value is 0.365 (kg s −1). The third scenario considers optimizing the power (P), the fresh water production (mf ), and the exergy destruction density (Exd). The power (P) has permanent value in three decision-making which is equal 311.105 (KW), also the fresh water production (mf ) is 1.816 (kg s −1) in three decision-making and besides the exergy destruction density (Exd) has a constant value in three decision-making which is 30.439 (W m−2). In all three scenarios, the decision-making methods, such as TOPSIS, FUZZY, and LINMAP were appropriate to specify the ultimate solution between the beam fronts. WOS:000604537000002 Q1 Q2

The aim of this research is to show the potential application of a photon enhanced thermionic emitter (PETE)–irreversible heat engine (HE) hybrid system. Solar energy has the greatest potential for clean energy, and thermionic emission is the alternative way to convert heat and light into electricity. PETE is an efficient solar to electricity converter comparing to other solar converters, which its efficiency can reach above 50%. Briefly, PETE–heat engine system is analyzed, where the PETE is the main cycle and HE is the bottom cycle. Receiving temperature to PETE above 1000 K and this heat can be utilized by a bottom cycle, heat rejected by the PETE is used by the heat engine, and additional power output is obtained. In addition to basic performance evaluation consisting of power output and electricity efficiency, some exergetic parameters are considered. These exergetic parameters can be listed as: exergy efficiency, depletion ratio, waste exergy ratio, exergetic sustainability index, exergetic ecological index, and modified exergetic ecological index. According to the results, power output, energy efficiency, exergy efficiency, sustainability index, ecological exergetic index, and modified ecological index are 63.698 W cm−2, 0.637, 0.721, 2.603, 0.652, and 0.477, for the optimum cathode temperature and for the optimum anode work function are 67.295 W cm−2, 0.673, 0.764, 3.312, 0.735, and 0.616 are possible to be achieved.

Energy is an important indicator of the powers and developments of countries in the world of global competition. There is a causal relationship between the level of economic development and electricity consumption in developing countries. Countries will achieve economic development if they ensure efficient production and distribution of electricity by considering the quality of life. High loss rates may occur in transmission and distribution networks in Turkey. This situation is seen as a point of improvement for energy distribution companies. The purpose of this study, the relative value of the activities of the energy distribution companies for electricity distribution in Turkey is to make the calculation. In the study comparing the effectiveness of existing 21 distribution companies operating in Turkey in 2019 it was carried out with DEA. In total, 4 models were selected as the CCR Model (Input and Output Oriented CCR Models) developed by Charnes, Cooper and Rhodes and the BCC Model (Input and Output Oriented BCC Models) developed by Charnes, Cooper and Rhodes. As a result, the efficiency values of 21 distribution companies were measured in the solution of the models with the EMS Version 1.3 package program and the relative efficiency ranking of the companies was obtained by including the Super Efficiency Model in the models in the EMS Version 1.3 program. This study will benefit decision makers in determining improvement goals, as it will provide perspective on effective distribution of electrical energy from different points such as scale-based returns and input / output orientation., Enerji, küresel rekabet dünyasında ülkelerin güçlerinin ve gelişmişliklerinin önemli bir göstergesidir. Gelişmekte olan ülkelerde ekonomik gelişme düzeyi ile elektrik tüketimleri arasında bir nedensellik ilişkisi bulunmaktadır. Ülkeler, yaşam kalitesini gözeterek elektriğin etkin üretimini ve dağıtımını sağladıkları takdirde ekonomik gelişme sağlayacaklardır. Türkiye’de iletim ve dağıtım şebekelerinde yüksek kayıp oranları oluşabilmektedir. Bu durum enerji dağıtım şirketleri açısından iyileştirme noktası olarak görülmektedir. Bu çalışmanın amacı, Türkiye’deki enerji dağıtım şirketlerinin elektrik dağıtımı için etkinlik değerlerinin göreli hesaplamasını yapmaktır. Çalışmada 2019 yılında Türkiye’de faaliyet gösteren 21 adet enerji dağıtım şirketinin mevcut dağıtım etkinliklerinin karşılaştırılması Veri Zarflama Analizi(VZA) ile yapılmıştır. Uygulamada VZA modellerinden ve Charnes, Cooper ve Rhodes tarafından geliştirilen CCR Modeli (girdi ve çıktı odaklı CCR Modeli) ile Banker, Charnes ve Cooper tarafından geliştirilen BCC modeli (girdi ve çıktı odaklı BCC) olmak üzere toplamda 4 model seçilmiştir. Sonuç olarak modellerin çözümünde EMS Version 1.3 paket programı ile 21 adet enerji dağıtım şirketine ait etkinlik değerleri ölçülmüş ve EMS Version 1.3 programına Süper Etkinlik Modeli’nin dahil edilmesi ile şirketlerin göreli etkinlik sıralaması elde edilmiştir. Bu çalışmanın, elektrik enerjisinin etkin şekilde dağıtımı konusunda, ölçeğe göre getiri ve girdi/çıktı yönelimi gibi farklı noktalardan bakış açısı sağlayacağı için iyileştirme hedeflerinin belirlemesinde karar vericilere fayda sağlayacağı düşünülmektedir.

Environmental concerns have gained great attention in the last decades, especially the global warming caused by usage of fossil fuels mostly. Renewable energy sources are the most reasonable way to decreasing the fossil fuel usage as a primary source and to preventing its environmental effects. In this regard, renewable source multigeneration systems seem to be an alternative. In this paper, a solar driven multigeneration system consisting of PV/T panels, a hydrogen fueled diesel engine generator, an electrolyzer, a hydrogen compressor, a hydrogen storage tank, batteries, an air cooled chiller, a hydrogen combustor, a water storage tank, and a control systems is considered. The simulation of this system is performed through TRNSYS 18. Outputs from the proposed system are heating, cooling, electricity and hydrogen. The performance analysis is done for Izmir, which is the third biggest city in Turkey by population while the obtained results are evaluated over a period of one year. Keywords: Air cooling chiller, Hydrogen, Multigeneration, Solar energy

The purpose of this study is to present an alternative trigeneration system consisting of a proton exchange membrane fuel cell (PEMFC), a chemical heat pump and an absorption refrigeration system. ...

Exergy is the very useful tool to evaluate energy systems besides energy analysis based on the first law of the thermodynamics. In contrast to energy, exergy is not conserved and always decreases. There are many types of exergy analysis involving exergoeconomic, exergoenvironmental, advanced exergy-based analyses, extended exergy analysis etc. In this study, an application of the extended exergy analysis is performed. In extended exergy analysis, not only energy related system is considered but also all materials and energy flows’ exergy, non-energetic and immaterial fluxes (capital, labor and environmental impact) are turned into exergy equivalent values and utilized in the analysis, which are calculating for local econometric and social data. These methods can be applied to societies or energy based or non-energy-based system. In this study, dynamic exergy analysis and extended exergy application of electricity generation from photon enhanced thermionic emitter is conducted. According to results, some important values can be listed as; extended exergy destruction, conventional based exergy destruction, extended exergy efficiency, conventional exergy efficiency, extended sustainability ratio, conventional sustainability ratio, extended exergy-based depletion ratio and conventional exergy-based depletion ratio are 542106006 MJ, 542084601 MJ, 0.01094, 0.01094, 1.011, 1.011, 0.978 and 0.989 respectively.

In this study, an alternative and new method to determine optimum insulation thickness is presented. This method combines economic and environmental effects, and is called as Combined Economic and Environment Method (CEEM). Analyses were carried out for outside walls for Bilecik, Turkey and rockwool and glasswool were chosen as insulation materials. The presented method was compared with economic and environmental approaches. The optimum insulation thicknesses of three different methods were calculated. Optimum points were determined as 0.176 m (CEEM), 0.133 m (economic approach) and 0.227 m (environmental approach) for the rockwool and 0.185 m (CEEM), 0.140 m (economic approach) and 0.467 m (environmental approach) for the glasswool. In addition, annual cost savings and energy savings were also determined.

Aim of this paper is to present an alternative environmental friendly energy system consisting of solar driven Stirling Engine, chemical heat pump and absorption refrigeration system. Solar energy is the main energy source and waste heat is rejected by the Stirling engine is utilized by the chemical heat pump and absorption refrigerator. This system presents an alternative environmental friendly energy system that produces electricity, cooling and heating same time. A parametric research is conducted considering power output, energy efficiency and exergy destruction rate. Results are obtained numerically and discussed. According to the results, system operates most efficiently at the high temperature ratio of the working fluids of the Stirling engine and high collector surface temperature. Maximum power output is 9.463 kW, maximum energy efficiency of the hybrid system is 0.337. Comparing these results with Stirling engine, maximum power output of the hybrid system increases 14% and energy efficiency increases 13% for the hybrid system.

Ülkelerin gelişmişlik ölçütlerinden birisi de enerji tüketimidir. Fosil yakıtların tükenebilirliği, atmosfere önemli miktarda CO₂ ve partikül madde salması, hava kirliliği ve küresel ısınma gibi çevre sorunlarına yol açmaktadır. Biyokütle enerjisinin kullanımı, yerli ve yenilenebilir enerji kaynaklarından yararlanmak, çevre sorunlarını azaltmak, istihdamı artırmak, ekonomiye katma değer yaratmak bakımından oldukça önemlidir. Hayli ekonomik bir kaynak olan biyogaz kırsal kalkınmanın sağlanması bakımından önemli bir potansiyeli bünyesinde barındırmaktadır. Eskişehir, hayvansal, bitkisel ve organik içerikli kentsel atıklar bakımından büyük bir potansiyele sahiptir. Bu çalışmada Eskişehir’in 2010-2019 yılları arasındaki hayvansal atıklarından elde edilebilecek biyogaz miktarı, bu miktardan elde edilebilecek enerji karşılığı, üretilebilecek enerjinin elektrik tüketimine oranı ve atmosfere verilecek CO₂ miktarının azaltılmasına olan yararı incelenmiştir. Eskişehir ilinin hayvan varlığı TÜİK’ten elde edilen verilerdir. Çalışmanın sonucunda toplanabilir gübre miktarı 2.050.383 ton/yıl olarak hesaplanmıştır. Bu miktardaki hayvansal atıktan elde edilen enerji, Eskişehir’in yıllık elektrik tüketiminin yaklaşık %8’ini karşılamaktadır. Eskişehir’de son on yılda görülen hayvan varlığındaki artış, hayvansal atıklardan üretilebilecek biyogaz enerjisinin sürdürülebilir olduğunu göstermektedir. Metan gazından üretilecek elektrik enerjisi sayesinde önemli miktardaki CO₂’in atmosfere salınımının azaltılabileceği hesaplanmıştır. Biyogaz tesislerinden atık olarak çıkan gübrenin tarımsal alanlarda kullanabilir olması, istihdama katkı sağlaması ve çevrenin temiz kalması bakımından da önemlidir., A development indicator of a country is its energy consumption. The exhaustion of fossil fuels causes environmental problems such as the release of significant amounts of CO₂ and particulate matter into the atmosphere, leading to global warming. Biomass energy is an important energy alternative for reducing environmental problems. The province of Eskisehir in Turkey produces massive amounts of animal, herbal, and organic urban waste suitable to obtain biofuel. This study aimed to determine the amount of biogas that could be obtained from the animal waste in Eskisehir between 2010 and 2019 as well as the energy amount that such waste could represent and the ratio of the energy that could be converted into electricity for consumption. The results show that 2,050,383 tons/year of fertilizer could be collected in the study period. This amount of animal waste could satisfy approximately 8% of Eskisehir’s annual electricity demand. Moreover, thanks to the electrical energy generated from methane gas, the release of a significant amount of CO₂ into the atmosphere could have been prevented. In addition to energy, the manure generated as waste from biogas facilities could be used in agriculture, contributing to economic development and maintaining the environment clean.

Renewable energy is an abundant and environmentally friendly local resource. The use, future, and development of wind energy, which is one of today's renewable energy resources, is of great importance. In this study, electrical energy production from wind energy has been examined in Turkey. The electrical energy production (GWh) data set belonging to the years 2010-2019 was used. Trend analysis of electrical energy generation (using three different models) has been evaluated using these data. These models are the linear, s-curve, and quadratic trend models. Then, the model with the minor result in MAPE, MAD, and MSD values was chosen. Finally, it was resolute that the most suitable model for electrical energy production is the quadratic trend model.

The construction industry uses large amounts of energy in building, heating, and cooling to achieve optimum thermal performance and acceptable comfort. Renewable energy is considered clean energy, and these resources should be used in the most appropriate way to minimize environmental impacts. Trombe wall is used to save energy in buildings. The Trombe wall's significant problem is that indoor temperature can reach above the 40 oC and this reasons to rise in cooling load. In this paper, a model has been developed for overcoming temperature growth in outdoor air in the summertime. In this model, a heat pipe is placed to the airflow channel for removing heat to be decreased indoor air. Also, an integrated wind turbine is installed in the building for electricity generation, and the results are evaluated.

The main objective of this study is to compare the two systems in terms of the thermoeconomic and the performance. The first one is called hybrid I and consists of high temperature polymer electrolyte membrane and thermocapacitive cycle. The second one is named hybrid II, which is composed of high temperature polymer electrolyte membrane and thermoelectric generator. Thermocapacitive cycle and thermoelectric generator have various advantages, such as generally lower cost and higher power density. So, they have good potential to utilize waste heat. The performance parameters of the considered hybrid systems include power density, energy efficiency, exergy efficiency and exergy destruction rate. The results have shown that hybrid I is more advantageous than hybrid II. The maximum power density values for hybrid I and hybrid II are obtained to be 2536.91W and 2049.62W while their energy efficiencies are 77.4% and 76.8%, respectively.

Purpose of this paper is to compare the performance of an alkali metal thermal electric converter (AMTEC) and thermoelectric generator (TEG) as a subsystem for utilizing rejected heat from the molten carbonate fuel cell (MCFC). AMTEC and TEG have various advantages such as; higher power density, no maintenance needed, silent and generally lower cost. Therefore, they have good potential to utilize waste heat. Performance parameters of systems are defined as power output density, exergy destruction rate density, energy and exergy efficiencies. Results show that the system MCFC-AMTEC hybrid system is more advantageous than the MCFC-TEG hybrid system. Some important results are listed follows; maximum power output densities for the MCFC-AMTEC and MCFC-TEG are 2425.833 (W/m(2)), and 1964.389 (W/m(2)), respectively, while efficiencies are %, 76.6% and 76.4 %. (C) WOS:000602755200002 1-s2.0-S2352484719307437 Q1 Q2

7th Global Conference on Global Warming, GCGW 2018 -- 24 June 2019 through 28 June 2019 -- -- 233979, Buildings cause to meanly one-third of carbon dioxide release and energy consumption. That is why, decreasing fuel consumption in building is the considerable aim for scientists and engineers. The easiest way of this is to insulate building walls. Insulation thickness optimization is conducted via a new method named as combined environmental and economic method (CEEM). Through this method, environmental costs are integrated in the fuel and insulation material costs. Environmental pollution cost of carbon dioxide, insulation materials and fuels are added to their cost, and total annual cost for the system is calculated and results are investigated according to insulation thickness. In this paper, insulation thickness optimization is researched for cooling applications. Results for the life cycle-integrated economic analysis and economic approach in terms of insulation thickness are presented. © Springer Nature Switzerland AG 2020.

In this paper, a phosphoric acid fuel cell (PAFC) – thermally regenerative electro-chemical cycle (TREC) hybrid system is investigated in terms of the different parameters including ecological function for different temperatures. Low temperature heat obtained by the PAFC is used by the TREC to generate electricity as a secondary power generator. Ecological function is applied to design an environmentally friendly hybrid system. Results are obtained numerically and an ecologically friendly operation range is attempted to determine for the considered system. According to results, the maximum power of the hybrid system is 885.60 W at 150 °C, 935.07 W at 180 °C, 949.07 W at 200 °C and the maximum ecological function is equal to 373.85 W at 150 °C, 431.63 W at 180 °C and 439.02 W at 200 °C and finally, the maximum efficiency is 0.754 at 150 °C, 0.780 at 180 °C and 0.784 at 200 °C. Finally, it is recommended that current density should be chosen between the current density at the maximum ecological function and current density at the maximum efficiency for a more efficient system.

Aim of this paper is to present a new exergetic index. This index is called exergetic ecological index and it is adopted from the ecological function that provides opportunity to compare power output (desired output) and exergy destruction (lost power). The bigger ecological function means the more efficient and environmental friendly energy system. However, this criterion does not give any information about relation with the exergy source and exergetic ecological index provides this comparison. Finally, exergetic ecological function includes product exergy, exergy destruction and exergy source in a one equation and enables to evaluate any energy system considering with these three parameter.

Since oil reservoirs have different properties, each reservoir performs differently during enhanced oil recovery (EOR) processes. In some cases, water injection is the most effective method, while in others, gas injection or other methods will result in better performance. Most reservoir simulations assume that the amount of injection fluid is sufficient. However, in practice, the amount of available gas is enough to supply only a limited number of reservoirs. This study presents a comprehensive model which examines oil reservoirs in concert based on mathematical programming, and considers the competition between them. This model entails sensitive analysis of gas injection projects in order to determine effective factors (technical and economic parameters) on decision-making relating to gas injection projects. Results show that technical and economic parameters such as oil price, gas quality and gas price variation have a marked effect on economic results and may lead to favorable economic conditions. Variations were made in the model regarding changes in interest rate, number of wells and injection pressure, but these variations did not lead to unfavorable economic conditions; in other words, changes in these factors had no significant effect on stability.

In the present study, an alternative method combining economic and environmental costs is suggested for the pipe insulation. This method is called as combined economic and environment method (CEEM)...

This paper is about an irreversible quantum spin-1/2 heat engine. Performance of the irreversible quantum heat engine including basic thermodynamic parameters, power output and energy efficiency, are considered, besides ecological function. Ecological function gives a possibility a comparison between power output and exergy destruction. The results show that power output and ecological function have maximum (optimum) points for different effectiveness values which are 0.9 and 0.8 and according to different magnetic field values . All parameters are compared with each other and it is found that the most convenient operation conditions are obtained at optimum ecological function.

Water scarcity and contamination of available water are becoming one of the most complex problems worldwide and they compromise economic development, global sustainability, and human supply, among others. Water is required in almost all human activities and also for planet equilibrium in terms of biodiversity. In this research a new home scaled water desalination plant, using a reverse osmosis technology and driven with solar energy is analyzed via extended exergy analysis, which is one of the most accurate methods for evaluating both energy performance and sustainability. The proposed system, that is presented and analyzed, consists of a solar concentrator having 1000 concentrating rate, a Photon Enhanced Thermionic Emitter, a Dye-Sensitized Solar Cell for the electricity generation and a Reverse Osmosis Desalination Plant (RODP) for water purification using the produced electricity. This system allows water desalination in small scale plants requiring low density energy sources and can produce sustainable water for multiples uses, such as domestic use or agricultural, among others. The most important results are labor and capital exergy equivalents, 42.68 MJ/workhour and 12.09 MJ/Euro, respectively, and an exergy destruction of 389.700 GJ for all the system annually. The proposed technology can be extended and used in different locations and the Extended Exergy Analysis can be used as a powerful tool for both design and optimization.

Introducing nanotechnology made a revolution in various industries such as upstream, downstream and energy industries. As a result, developing new types of nanoscale thermal cycles can develop the future of energy systems. The present work investigated a nanoscale irreversible Stirling refrigeration cycle thermodynamically in order to optimize the performance of the aforesaid cycle. In the above-mentioned cycle, an Ideal Maxwell–Boltzmann gas plays a role of a working fluid. Ideal Maxwell–Boltzmann gas was employed for working fluid in the cycle. Owing to the quantum limit influence on the gas particles restricted in the finite area, the cycle no longer retains the circumstance of perfect regeneration. He4 is chosen as working fluid. This paper demonstrates two different plans in the process of multi-objective optimization; though, the results of each plan are assessed individually. The first scenario constructed with the purpose of maximizing the ecological coefficient of performance (ECOP), the coefficient of performance ( C O P ) and the dimensionless Ecological function ( e c f ). Furthermore, the second scenario planned with the purpose of maximizing the exergy efficiency ( η e x ), the coefficient of performance ( C O P ) and the dimensionless Ecological function ( e c f ). All the scenarios in this paper are performed through the multi-objective evolutionary algorithms (MOEA) joined with NSGA II approach. Moreover, to determine the final solution in each scenario three effective decision makers are employed. Deviation of the results obtained in each scenario and each decision maker are calculated individually. Finally, the results of the suggested scenarios were compared to each other, and it reveals that when the exergy efficiency achieved the maximum value, the values of COP, ECOP, and ecf also maximized.

The aim of this paper is to determine lost works in a molecular engine and compare results with macro (classical) heat engines. Firstly, irreversible thermodynamics are reviewed for macro and molecular cycles. Secondly, irreversible thermodynamics approaches are applied for a quantum heat engine with -1/2 spin system. Finally, lost works are determined for considered system and results show that macro and molecular heat engines obey same limitations. Moreover, a quantum thermodynamic approach is suggested in order to explain the results previously obtained from an atomic viewpoint., 32 pages, 2 Tables, 1Figure

An irreversible hybrid solid oxide fuel cell (SOFC)-Brayton heat engine system is taken into account in this study. Ecological based thermoenvironmental function is considered to assess the performance of the system as well as the power, exergy destruction, energy and exergy efficiencies. This function enables someone to determine environmental impact of any thermal cycle. Optimum operating conditions for all investigated parameters are obtained. Results are presented numerically and discussed. Some important results are; maximum power density of the hybrid system is 15260.9 (W m−2) at i = 17,000 (A m−2), maximum energy efficiency of the hybrid system is 0.841 at i = 7200 (A m−2), exergy efficiency of the hybrid system is 0.676 at i = 5200 (A m−2) and ecological based thermoenvironmental function density of the hybrid system reaches maximum value at i = 5800 (A m−2) and it is equal to 0.00603 (W m pts−1 m2). Finally, environmental friendly and efficient operation conditions, if ≤ i ≤ iP, is suggested for the hybrid system.

A hybrid, irreversible solid oxide fuel cell – Stirling heat engine system is taken into account. Thermoenvironmental criterion approach, which enables to evaluate environmental impact of any thermal cycle, is applied to the considered system for the first time. Power density, exergy density, thermoenvironmental function density, energy and exergy efficiencies are considered. Results are presented and discussed to determine optimum operating conditions. Some important results for the hybrid system are ordered: maximum power density is 7489.92 (A m−2), maximum energy and exergy efficiencies are 0.800 and 0.887, respectively, and finally, thermoenvironmental function density is 0.0276 (W mpts−1 m−2).

Advanced exergy analysis has gained great importance as a comprehensive evaluation tool for energy conversion systems in recent years. In this regard, splitting the exergy destruction into avoidable/unavoidable parts has enabled us to identify the improvement potential of component while endogenous/exogenous parts of the exergy destruction have been detailed studied to get more information about interactions among the components. An ice rink refrigeration system was investigated using both conventional and advanced exergoeconomic analyses in this paper. The ice rink refrigeration system has a cooling load of 300 kW and ammonia was chosen as refrigerant. Exergy destruction, investment cost rates and exergy destruction cost rates based on these two analyses were calculated first. Endogenous/exogenous and avoidable/unavoidable parts of the exergy destruction, investment cost rates and exergy destruction cost rate for each system component were then presented. Finally, possible solutions to reducing inefficiencies were discussed. It was determined that 47.15% of the total exergy destruction of the system was avoidable while 22.89% of the total exergy destruction of the system was exogenous. The evaporator with 18% endogenous available investment cost rate and the condenser with 64.3% endogenous available exergy destruction cost rate were the two most important components in the ice rink refrigeration system.

An irreversible hybrid molten carbonate fuel cell-Braysson heat engine is taken into account. Basic thermodynamics parameters including power output, efficiency and exergy destruction rate are considered. In addition ecological function and new criteria, which is based on ecological function, for heat engines called as modified ecological function is suggested. Optimum conditions for mentioned parameters above are determined. Numerical results are obtained and plotted. Finally, results are discussed.

In this study, the thermophotovoltaic (TPV)-driven thermionic refrigerator (TIR) is presented as an alternative refrigerator operated by the solar energy. Solar energy is the main energy source and its performance is analyzed. Power output density of the TPV, cooling rate density, COP, exergy destruction rate densities, and exergy efficiencies are the considered parameters. Calculations are performed numerically; results are presented and discussed. The most suitable operation conditions are defined. According to the results, the cooling rate density is 648 W/m2, power output densities are 1189.86 W/m2 and 667.234 W/m2 for the eg = 0.3 eV and eg = 0.4 eV, and the exergy efficiency of the system is about 0.071.

Primary energy sources, fossil fuels mostly, have been depleting and not only in industrial and commercial sectors, but also in residential applications affect negatively the environment. One of the important solutions to these problems depends on renewable energy usage widely. One has focused on renewable energy-based multigeneration systems in the last decade. In this paper, a solar driven multigeneration system is introduced and the simulation of this system is performed by using TRNSYS 18. The proposed system includes PV-T and PV panels, a solid oxide fuel cell (SOFC), an electrolyzer, a hydrogen compressor, a hydrogen storage tank, a generator, a gas turbine cycle, batteries, an air-cooled chiller, an absorption chiller, hydrogen combustors, a water storage tank, a heat exchanger and control systems. In this system, the producing heat, cooling, electricity and hydrogen are designed. This system is considered to be located in Izmir, which is the third biggest in Turkey by population and the performance of the system is analyzed over a period of one year.