Article
Green & Sustainable Science & Technology
Martin Nwodo, Chimay J. Anumba
Summary: By applying an exergy-based LCA method to three case-study buildings, this study demonstrates the theoretical benefits of exergy-based LCA over conventional LCA, including improved characterization and valuation, accuracy, and comparability of environmental impacts.
Article
Energy & Fuels
Abbas Aghagoli, Mikhail Sorin, Mohammed Khennich
Summary: Heat pump system is widely used due to its advantages of high energy efficiency, reliability, and environmental impact. However, the major drawback of the system is the exergy loss during the isenthalpic process in the expansion valve. This paper investigates the integration of Tesla turbine exergy analysis with the heat pump system to reduce exergy losses and increase coefficient of performance and exergy efficiency.
Article
Energy & Fuels
Alireza Pirmohamadi, Hadi Ghaebi, Behrooz M. Ziapour, Mohammad Ebadollahi
Summary: This study proposed a nitrogen Brayton cycle system for sodium-cooled fast reactors, and the integration of the topping system with bottoming cycles improved the system performance. Energy, exergy, and exergoeconomic analyses showed that the system had a thermal efficiency of 34% and an exergetic efficiency of 62%, with the topping system of the nitrogen Brayton cycle being the main cause of exergy destruction.
Article
Thermodynamics
Nico Haggqvist, Tor-Martin Tveit, Ron Zevenhoven
Summary: For industrial applications, accurately monitoring the condition of critical equipment and maximizing performance under varying operating conditions is crucial. However, it is often difficult to directly measure important parameters for monitoring and optimization, requiring estimation. This study presents and validates a model that simulates cyclic temperature variations in an industrial Stirling cycle-based high temperature heat pump, using measured cylinder pressures and slow-changing temperature data. This model will be used for online monitoring and system performance optimization.
CASE STUDIES IN THERMAL ENGINEERING
(2023)
Article
Thermodynamics
Riying Wang, Jianying Hu, Zilong Jia, Depeng Chang, Limin Zhang, Ercang Luo, Yanlei Sun, Zhanghua Wu, Yanyan Chen
Summary: Heat pump technology, especially Stirling heat pumps, has gained attention due to their high efficiency, environmental friendliness, and ability to operate at various temperatures. This paper presents a novel heat-driven double-acting free-piston Stirling heat pump system with multiple units, simplifying the design complexity and improving system reliability and efficiency.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Thermodynamics
Weijia Huang, Yufei Liu, Danxing Zheng, Xiaohui Chen, Mo Yang, Yun Li, Xiaoxiao Li
Summary: This study proposed a new exergy-environment assessment method for energy systems, applied to a sludge digestion system as a case study, demonstrating the feasibility and advantages of the proposed method.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Thermodynamics
Z. Y. Xu, J. T. Gao, Bin Hu, R. Z. Wang
Summary: The study compares the efficiency of compression and absorption heat pumps, revealing that compression heat pumps have higher coefficient of performance but lower exergy efficiency, while absorption heat pumps are more effective at higher temperature differentials.
Article
Thermodynamics
Mengdi Cui, Baolong Wang, Cuiling Wang, Falin Wei, Wenxing Shi
Summary: An integrated system of vapor compression cycle and heat exchanger network is proposed for efficient heating and cooling. The existing construction methods of integrated systems are not optimal and cannot be integrated with external heat exchanger networks. This study introduces the GraPHsep method, which achieves one-step optimization of the integrated structures of vapor compression cycles and external heat exchanger networks, resulting in significantly higher coefficient of performance (COP) compared to existing systems.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Environmental Sciences
Mohammadali Kiehbadroudinezhad, Homa Hosseinzadeh-Bandbafha, Keikhosro Karimi, Meysam Madadi, Yusuf Chisti, Wanxi Peng, Dan Liu, Meisam Tabatabaei, Mortaza Aghbashlo
Summary: Life cycle assessment was used to evaluate the environmental impacts of phytoplanktonic biofuels as sustainable alternatives to fossil fuels. Three scenarios were examined, involving the conversion of planktonic biomass into valuable commodities and energy streams. The results showed that the second and third scenarios had reduced potential for damaging human health and environmental impact, as well as reduced cumulative exergy demand compared to the first scenario. Therefore, producing chemicals and utilities within the biorefinery could significantly improve environmental sustainability, reduce waste, and diversify revenue streams.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Agronomy
Andi Mehmeti, Kledja Canaj, Francesca Boari, Vito Cantore, Mladen Todorovic, Nicola Calabrese
Summary: This study compared the resource use and environmental impacts of globe artichoke production using seed propagated (SP) and vegetative propagated (VP) methods. The results showed that VP artichokes had lower resource use and environmental impacts per hectare of land, but higher impacts per ton of product. SP artichokes had lower impacts in certain indicators but higher impacts in others.
Article
Thermodynamics
Riying Wang, Jianying Hu, Zilong Jia, Limin Zhang, Ercang Luo
Summary: This study investigates the performance of an electrically driven free-piston Stirling heat pump system, showing efficient heating in low temperature environments and detailed analysis of its operational characteristics under different temperature conditions.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Thermodynamics
Hongsheng Zhang, Xingang Liu, Yifeng Liu, Chenghong Duan, Zhan Dou, Jiyun Qin
Summary: The novel cogeneration system proposed in the paper effectively increases power generation and heating load, reduces standard coal consumption rate and total exergy loss, and improves total energy and exergy efficiency.
Review
Energy & Fuels
Andrea Aquino, Flavio Scrucca, Emanuele Bonamente
Summary: Geothermal heat pumps have high energy output, but utilizing low-enthalpy geothermal energy presents sustainability issues. Life-cycle analyses show that installation and operation stages have the highest environmental impacts, leading to optimization studies focusing on system thermodynamics to maximize energy performance through component design. Environmental studies investigate how climate and ground properties impact system sustainability and identify suitable locations for geothermal exploitation.
Article
Thermodynamics
Alpaslan Alkan, Ahmet Kolip, Murat Hosoz
Summary: The study compared the energy and exergy performance of an automotive heat pump (AHP) with R1234yf and R134a, finding that while the R1234yf system had slightly lower conditioned air temperature, heating capacity, and coefficient of performance (COP), it had lower total exergy destruction rate and TEWI in comparison with the system using R134a. Additionally, the R1234yf system showed larger exergy destruction in outdoor unit, compressor, and expansion device but lower exergy destruction in the indoor unit.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Thermodynamics
Fariba Mehdizadeh, Nassim Tahouni, M. Hassan Panjeshahi
Summary: This research introduces a new graphical tool called Omega Total Site Profile (OTSP) for calculating exergy destruction and losses within a total site. By combining this tool with mathematical optimization, a method for designing or retrofitting a total site is presented. Two case studies demonstrate the effectiveness of the tool and method.
