Article
Construction & Building Technology
Emin Acikkalp, Arif Hepbasli, Ana I. Palmero-Marrero, David Borge-Diez
Summary: Different definitions of Zero-Energy Building (ZEB) have been proposed, including zero energy, zero carbon, zero exergy, and zero cost. This study introduces the concept of net zero extended exergy buildings, which combines extended exergy and net zero exergy building concepts to measure the exergetic footprint. The proposed methodology is applied to a building, and the results indicate the required peak power and electrical energy for meeting the electricity demand.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Energy & Fuels
A. Picallo-Perez, J. M. Sala-Lizarraga, C. Escudero-Revilla, J. M. Hidalgo-Betanzos, I Ruiz de Vergara
Summary: In this study, thermoeconomics is used to evaluate the cost distribution of a central thermal system consisting of a cogeneration engine, an aerothermal heat pump, and a natural gas condensing boiler. The combination of cogeneration systems with renewable energy technologies is attractive in the building industry, however, the use of cogeneration systems with active envelope solutions is rare and efforts to enhance the synergies between these systems are even scarcer. By applying thermoeconomics, the complex and innovative system can be analyzed and diagnosed, leading to improved energy efficiency.
FRONTIERS IN ENERGY RESEARCH
(2022)
Article
Thermodynamics
Xiaohui Zhong, Tao Chen, Xiangyu Sun, Juanjuan Song, Jiajun Zeng
Summary: This study conducted exergy analysis on a novel wind-to-heat system and investigated its thermodynamic performances using experimental data. The wind turbine and the compressor of the heat pump subsystem were found to be the most critical components in the system. Through mathematical modeling and exergy analysis, it was discovered that the system's exergy destruction could be reduced by optimizing internal structure parameters and considering interactions with other components.
Article
Thermodynamics
Lixing Zheng, Yangdi Hu, Changning Mi, Jianqiang Deng
Summary: This study investigates the exergetic performance of a CO2 two-phase ejector and explores the interactions among its components. The results show that the mixing chamber is the component with the largest exergy destruction, followed by the motive nozzle, diffuser, and suction chamber. The optimization potential of the components in terms of exergy destruction is ranked as follows: motive nozzle, diffuser, mixing chamber, and suction chamber. Reducing the suction flow temperature and ejector area ratio can decrease the avoidable exergy destruction. The study provides valuable insights for optimizing the efficiency of ejectors.
APPLIED THERMAL ENGINEERING
(2022)
Article
Energy & Fuels
Emin Acikkalp, Hakan Caliskan, Hiki Hong, Hongjie Piao, Dohyun Seung
Summary: In this paper, a photovoltaic-thermal (PVT) module based desiccant air-cooling system for buildings is analyzed using extended exergy analysis. The results show that extended exergy analysis provides different results from conventional exergy analysis in terms of exergy destruction and exergy efficiency. The exergy equivalent of capital has the highest portion, mainly due to the significant expenses of electricity consumption. Therefore, it is important to increase exergy efficiency and reduce exergy destruction.
Article
Energy & Fuels
Emin Acikkalp, Hakan Caliskan, Hiki Hong, Hongjie Piao, Dohyun Seung
Summary: In this study, a PVT module based desiccant air-cooling system for buildings is analyzed using extended exergy analysis, revealing differences in exergy destruction and efficiency compared to conventional analysis, with electricity consumption being the main contributor to exergy destruction.
Article
Engineering, Chemical
Zhiqiang Liu, Zhixiang Zeng, Chengwei Deng, Nan Xie
Summary: This research conducts exergy analysis and advanced exergy analysis of an absorption chiller/Kalina cycle integrated system, obtaining the exergy destruction of each component and overall exergy efficiency of the cascade process. Advanced exergy analysis investigates the interactions among different components and the actual improvement potential.
Article
Thermodynamics
Emin Acikkalp, Hakan Caliskan, Onder Altuntas, Arif Hepbasli
Summary: A novel combined extended-advanced exergy analysis method has been developed and applied to a gas turbine system for a case study, showing its variability. The method integrates various thermodynamic analysis methodologies to assess all input parameters including labor, capital, and environment with better efficiency.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Thermodynamics
M. Fallah, Z. Mohammadi, S. M. Seyed Mahmoudi
Summary: The study investigates the irreversibility and improvement potential of the combined supercritical carbon dioxide and organic Rankine cycle. It reveals that a significant portion of exergy destruction can be avoided, with a majority being endogenous and modifiable by altering components. High temperature recuperator, turbine1, and pre-cooler1 are identified as having the highest priority for improvement.
Article
Thermodynamics
Zahra Mohammadi, Mohsen Fallah
Summary: A comparative and comprehensive investigation was conducted on the six different layouts of supercritical carbon dioxide cycle based on conventional and advanced exergy. The effect of different layouts on exogenous exergy destruction of each component was studied for the first time. Advanced exergy analysis provided different priority suggestions for improving components of each cycle compared to conventional exergy analysis. The pre-compression cycle showed the most potential for development, while the partial cooling cycle had the highest impact on exogenous exergy destruction, followed by the recompression and intercooling cycles.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Thermodynamics
Yuan Zhang, Erren Yao, Zhen Tian, Wenzhong Gao, Ke Yang
Summary: Compressed Carbon dioxide Energy Storage (CCES) system is a novel technology for energy storage, offering a solution to the instability of renewable energy sources. Research has shown that utilizing both conventional and advanced exergy analysis can optimize system performance and improve overall exergy efficiency.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Xiaoxia Xia, Zhipeng Liu, Zhiqi Wang, Qingsong Zuo, Tong Sun
Summary: Global issues such as energy crisis and environmental pollution have driven the development of waste heat recovery technology. The organic Rankine cycle (ORC)-vapor compression refrigeration (VCR) combined system is a promising solution to achieve refrigeration requirements by recycling waste heat. It is of great significance to determine the irreversible losses of the system and the improvement priority of the components in order to enhance the system performance.
APPLIED THERMAL ENGINEERING
(2023)
Article
Energy & Fuels
Xianzhi Tang, Gongxing Yan, Azher M. Abed, Aman Sharma, Elsayed Tag-Eldin, Yashar Aryanfar, Jorge Luis Garcia Alcaraz
Summary: This paper identifies the inefficiency of the studied energy conversion system using advanced exergy analysis to reduce losses and improve performance. The main role of advanced exergy analysis is to provide information by isolating exergy destruction, helping engineers improve system design and performance.
Article
Energy & Fuels
Yingnan Tian, Tong Zhang, Ningning Xie, Zhen Dong, Zeting Yu, Mingxin Lyu, Yanhua Lai, Xiaodai Xue
Summary: Identifying the main sources of exergy destruction is crucial for optimizing the performance of compressed air energy storage (CAES) systems. This study applied advanced exergy analysis to an adiabatic CAES power plant and found that the internal exergy destruction of the main components was more significant than the external exergy destruction. The third-stage heat exchanger (HEX3) was identified as having the highest optimization value among the components, followed by HEX2 and HEX1.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Thermodynamics
Abid Ustaoglu, Hande Torlakli, Alper Ergun, Ertugrul Erdogmus, Mehmet Emin Akay
Summary: This study evaluates the performance of an ORC-based solid waste-powered cogeneration system using conventional and advanced exergy analysis methods. Different working fluids are selected for evaluation and the effect of cycle parameters is examined. The study also identifies improvement potentials and the interaction between components using advanced exergy analysis. The highest thermal and exergy efficiency values are achieved and R141b is found to be the best working fluid. The study emphasizes the importance of system improvements in reducing exergy destruction.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Energy & Fuels
Ozgur Balli, Selcuk Ekici, Hikmet T. Karakoc
Summary: The research discusses the issues, opportunities, and benefits of a combined heat and power system, particularly focusing on the performance and environmental assessment of a micro gas turbine engine (M-CHP) system.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Thermodynamics
Irem Turk, Emre Ozbek, Selcuk Ekici, T. Hikmet Karakoc
Summary: Solar energy is an alternative energy source to fossil fuels, it is unlimited and nondestructive to nature. A solar-powered UAV with six hours of endurance is designed and evaluated, showing its potential for efficient flight in certain climate conditions.
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2022)
Article
Thermodynamics
Burak Tarhan, Ozge Yetik, Tahir Hikmet Karakoc
Summary: The current challenges in the aviation industry, such as energy needs and environmental pollution, have led to the adoption of lithium-derived batteries with a battery management system (BMS) to ensure ideal operating conditions. A hybrid BMS system has been designed to control and measure multiple battery types for electric aircraft, enhancing safety and reliability.
Article
Thermodynamics
David Borge-Diez, Daniel Icaza, Diego Francisco Trujillo-Cueva, Emin Acikkalp
Summary: The research analyzes the potential of decarbonization using heat pumps, with a case study conducted in Spain. The results show that this technology can serve as a worldwide solution for emissions reduction and energy efficiency improvement.
Article
Energy & Fuels
Ozge Yetik, Tahir Hikmet Karakoc
Summary: In this study, the cooling effect of 15 prismatic batteries connected in series was compared using air and alumina nanofluid. The results showed that the nanofluid can effectively keep the battery at a safe operating temperature under certain conditions.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Review
Thermodynamics
Alper Dalkiran, Murat Ayar, Utku Kale, Andras Nagy, T. Hikmet Karakoc
Summary: The study focuses on analyzing the impact of airport operations and investments in a comprehensive manner, with a particular emphasis on the concept of green airports. The findings suggest that economic efficiency and design themes are of primary importance, followed by environmental concerns.
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2022)
Editorial Material
Thermodynamics
T. Hikmet Karakoc, Can Ozgur Colpan, Selcuk Ekici, Ozge Yetik
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2022)
Article
Thermodynamics
Ozgur Balli, T. Hikmet Karakoc
Summary: This study presents a detailed analysis of exergy, exergoeconomic, environmental damage cost and impact of the aircraft engine turbofan (ATFE) in the aerospace industry. The results indicate the need to reduce waste exergy rate to improve exergy efficiency and sustainability index of the turbofan engine.
Article
Energy & Fuels
Ozgur Balli, Utku Kale, Daniel Rohacs, T. Hikmet Karakoc
Summary: This study presents a comprehensive investigation of the emission impact, environmental damage cost, exergoenvironmental and life cycle assessment (LCA) analyses of a micro turbojet engine (m-TJE) utilized on Unmanned Air Vehicle (UAV) for four different operating cases. The study shows that an increase in engine product rate reduces specific emission impact, specific environmental damage cost, specific exergy cost, specific exergoenvironmental impact, and relative exergoenvironmental impact difference of engine production.
Article
Thermodynamics
Duran Calisir, Selcuk Ekici, Adnan Midilli, T. Hikmet Karakoc
Summary: This study investigates the environmental impacts of using different power groups in a fixed-wing UAV, and finds that using a hybrid power group can reduce global warming, terrestrial ecotoxicity, photochemical oxidation, and other environmental impacts.
Article
Thermodynamics
Cem Tahsin Yucer, Yavuz Nacakli
Summary: The main purpose of this study is to analyze the performance of a small-scale turbojet engine for UAVs when different blend ratios of kerosene with diesel are necessary. Comparative analysis was performed to understand the effects of different diesel rates on the jet engine's performance. The performance parameters evaluated were specific fuel consumption, thrust, overall exergy efficiency, and air-to-fuel ratio.
INTERNATIONAL JOURNAL OF ENGINE RESEARCH
(2023)
Review
Multidisciplinary Sciences
Daniel Rohacs, Onur Yasar, Utku Kale, Selcuk Ekici, Enver Yalcin, Adnan Midilli, T. Hikmet Karakoc
Summary: This study reviews articles from open literature that examine particle image velocimetry techniques, focusing on components such as lasers, cameras, lenses, tracers, computers, synchronizers, and seeders. The evaluation results are categorized and explained using tables and figures. The study serves as a starting point for researchers and industrial companies interested in studying and implementing PIV experiments, as well as providing insights into the advantages and disadvantages of past and current technologies and potential upgrades for existing PIV laboratories.
Article
Transportation
Selcuk Ekici, Murat Ayar, Ugur Kilic, T. Hikmet Karakoc
Summary: This study examines the noxious emissions caused by equipping two types of aircraft offered by different manufacturers in the industry with the most commonly used engine combinations for commercial aviation on the same route and trajectory. The research utilizes the latest databases such as BADA v4.2_1, ANP v2.3, and ICAO EDDB25/FOCA to analyze fuel consumption and emissions in four different scenarios during identical flight operations. It also proposes a systematic aircraft-engine pair decision mechanism and a comprehensive computer simulation method for fuel consumption and emissions analysis.
JOURNAL OF AIR TRANSPORT MANAGEMENT
(2023)
Review
Engineering, Aerospace
Hursit Degirmenci, Alper Uludag, Selcuk Ekici, T. Hikmet Karakoc
Summary: This paper provides a historical overview of hydrogen-powered aviation and analyzes the critical components of the hydrogen supply network. As part of the Sustainable Development Goals, the study presents a future-oriented concept and discusses the challenges and prospects for decarbonization.
PROGRESS IN AEROSPACE SCIENCES
(2023)
Review
Chemistry, Physical
Onur Yasar, Emre Ozbek, Selcuk Ekici, Enver Yalcin, Adnan Midilli, T. Hikmet Karakoc
Summary: Fuel cells are a promising system utilized in various sectors, and particle image velocimetry is a practical technique for exploring the flow field inside fuel cells. Research on fuel cells focusing on particle image velocimetry technique has been reviewed, with discussions on system design, performance improvement, and cost benefit efforts affected by flow and design parameters.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Construction & Building Technology
Samiran Khorat, Debashish Das, Rupali Khatun, Sk Mohammad Aziz, Prashant Anand, Ansar Khan, Mattheos Santamouris, Dev Niyogi
Summary: Cool roofs can effectively mitigate heatwave-induced excess heat and enhance thermal comfort in urban areas. Implementing cool roofs can significantly improve urban meteorology and thermal comfort, reducing energy flux and heat stress.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Qi Li, Jiayu Chen, Xiaowei Luo
Summary: This study focuses on the vertical wind conditions as a main external factor that limits the energy assessment of high-rise buildings in urban areas. Traditional tools for energy assessment of buildings use a universal vertical wind profile estimation, without taking into account the unique wind speed in each direction induced by the various shapes and configurations of buildings in cities. To address this limitation, the study developed an omnidirectional urban vertical wind speed estimation method using direction-dependent building morphologies and machine learning algorithms.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Xiaojun Luo, Lamine Mahdjoubi
Summary: This paper presents an integrated blockchain and machine learning-based energy management framework for multiple forms of energy allocation and transmission among multiple domestic buildings. Machine learning is used to predict energy generation and consumption patterns, and the proposed framework establishes optimal and automated energy allocation through peer-to-peer energy transactions. The approach contributes to the reduction of greenhouse gas emissions and enhances environmental sustainability.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Ying Yu, Yuanwei Xiao, Jinshuai Chou, Xingyu Wang, Liu Yang
Summary: This study proposes a dual-layer optimization design method to maximize the energy sharing potential, enhance collaborative benefits, and reduce the storage capacity of building clusters. Case studies show that the proposed design significantly improves the performance of building clusters, reduces energy storage capacity, and shortens the payback period.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Felix Langner, Weimin Wang, Moritz Frahm, Veit Hagenmeyer
Summary: This paper compares two main approaches to consider uncertainties in model predictive control (MPC) for buildings: robust and stochastic MPC. The results show that compared to a deterministic MPC, the robust MPC increases the electricity cost while providing complete temperature constraint satisfaction, while the stochastic MPC slightly increases the electricity cost but fulfills the thermal comfort requirements.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Somil Yadav, Caroline Hachem-Vermette
Summary: This study proposes a mathematical model to evaluate the performance of a Double Skin Facade (DSF) system and its impact on indoor conditions. The model considers various design parameters and analyzes their effects on the system's electrical output and room temperature.
ENERGY AND BUILDINGS
(2024)
Article
Construction & Building Technology
Ruijun Chen, Holly Samuelson, Yukai Zou, Xianghan Zheng, Yifan Cao
Summary: This research introduces an innovative resilient design framework that optimizes building performance by considering a holistic life cycle perspective and accounting for climate projection uncertainties. The study finds that future climate scenarios significantly impact building life cycle performance, with wall U-value, windows U-value, and wall density being major factors. By using ensemble learning and optimization algorithms, predictions for carbon emissions, cost, and indoor discomfort hours can be made, and the best resilient design scheme can be selected. Applying this framework leads to significant improvements in building life cycle performance.
ENERGY AND BUILDINGS
(2024)
