Energy Conversion and Management最新文献

{"title":"Annual space heating and cooling carbon dioxide system based on hybrid techniques of ejector and integrated mechanical subcooling: Optimization and energy, exergy, environment and economic evaluation throughout the world","authors":"Baomin Dai ,&nbsp;Peifang Yang ,&nbsp;Shengchun Liu ,&nbsp;Ruirui Zhao ,&nbsp;Xuan Li ,&nbsp;Xiangjun Wang","doi":"10.1016/j.enconman.2025.119749","DOIUrl":"10.1016/j.enconman.2025.119749","url":null,"abstract":"<div><div>A novel air source transcritical carbon dioxide heating and cooling system employing the techniques of both ejector and integrated mechanical subcooling is suggested. The innovative system is designed to fulfill the annual heating and cooling demands of residential buildings. Different cities from diverse climate zones across the globe are selected as application scenarios. A comprehensive energy, exergy, environment, and economic evaluation model for the system is developed. Coefficient of performance is set as the objective function, and discharge pressure and subcooling degree is optimized using genetic algorithm. The results are compared with the traditional solutions, including baseline system, ejector system, integrated mechanical subcooling system, traditional heating and cooling system using difluoromethane as working fluid, and fossil fuel-fired boiler. The results demonstrate the coefficient of performance and annual performance factor of the new system can be increased by 4.32 ∼ 37.74 % and 7.16 ∼ 38.25 %. The exergy efficiency is 4.24 ∼ 46.02 % and 6.92 ∼ 46.12 % higher than that of the baseline system, ejector system and integrated mechanical subcooling system in heating and cooling mode, respectively. The life cycle climate performance of the new system demonstrates a significant reduction, ranging from 6.67 ∼ 72.90 %, when compared to the other solutions across 10 representative cities. The life cycle cost of the new system can be diminished by 3.44 ∼ 19.11 % in contrast to the baseline system, ejector system and integrated mechanical subcooling system. In comparison with the difluoromethane system, the payback period of the new system is 2.64 ∼ 7.07 years less than that of the ejector system and integrated mechanical subcooling system. This research can serve as a reference for the enhancement and optimization of air source transcritical carbon dioxide heating and cooling systems for residential buildings.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119749"},"PeriodicalIF":9.9,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and performance analysis of a tidal ducted turbine considering rotor-duct interaction","authors":"Yunlei Mei ,&nbsp;Fengmei Jing ,&nbsp;Xinru Wang ,&nbsp;Bin Guo ,&nbsp;Song Wang ,&nbsp;Qiang Lu","doi":"10.1016/j.enconman.2025.119758","DOIUrl":"10.1016/j.enconman.2025.119758","url":null,"abstract":"<div><div>This paper constructs a multi-objective optimization design method for ducted turbines by combining Computational Fluid Dynamics with Response Surface Methodology and NSGA-II algorithm. The optimization objectives is to achieve the maximum power coefficient. The design variables include the duct angle, duct length, tip clearance, and rotor axial position. Firstly, a simulation model of the ducted turbine was established and validated through experimental data from a towing tank. Secondly, a regression equation between the duct structure design variables and the optimization objectives was constructed using response surface methodology. Finally, the NSGA-II algorithm was employed to optimize the objectives, and the hydrodynamic and flow field characteristics of the ducted turbine were analyzed. The results indicate that the maximum <em>C_P</em> value of the ducted turbine reached 0.791, representing a 104.9% increase compared to the open turbine. In addition, the kinetic energy of the wake of the ducted turbine is lower, and its near-field wake velocity deficit is 44.05% higher than that of the open turbine. Due to the interaction between the duct-shedding vortex and the blade tip vortex, the diffusion range of the ducted turbine wake is broader, and the wake recovery is faster. At the downstream 7D, the degree of wake recovery is basically consistent with that of the open turbine. Finally, the duct alters the operating conditions of the blades. In the future, the blades can be optimized based on the radial flow distribution within the duct, which will further enhance the output power.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119758"},"PeriodicalIF":9.9,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reducing carbon footprint in ports through electrification and flexible energy management of ships","authors":"Giovanni Barone ,&nbsp;Annamaria Buonomano ,&nbsp;Gianluca Del Papa ,&nbsp;Giovanni Francesco Giuzio ,&nbsp;Adolfo Palombo","doi":"10.1016/j.enconman.2025.119742","DOIUrl":"10.1016/j.enconman.2025.119742","url":null,"abstract":"<div><div>The environmental impact of maritime transport has become a central concern for the international community. The Carbon Intensity Indicator and the Emissions Trading System are key mechanisms pushing the shipping sector towards more sustainable and less polluting solutions, including the adoption of alternative technologies to diesel generators and the reduction of heavy fuel oil employment. Port areas are particularly controlled, as the environmental impact of shipping operations affects both the environment and human-inhabited areas. Given that the electrification of ports (cold ironing) is not yet widespread globally, this work proposes an on-board poly-generation system equipped with high-temperature proton exchange membrane fuel cells and batteries to meet energy demands during entry, dock, and exit from port areas. Various operational strategies (rule-based energy system management) for managing on-board technologies are analysed, offering a range of potential applications based on the on-board availability of hydrogen and battery discharge modes, with the aim of reducing the ship’s environmental impact in port areas. Additionally, to fully electrify the poly-generation system, this study explores replacing auxiliary oil-fired boilers with heat pumps for steam production, integrating this technology into the low-temperature engine cooling circuit to enhance energy efficiency and eliminate emissions from auxiliary systems. By implementing these technologies alongside the developed operational strategies, it is possible to achieve an 80–90% reduction in carbon dioxide emissions in the port area, improving the carbon intensity indicator by 4.74%, from 11.06 to 10.38.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119742"},"PeriodicalIF":9.9,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance optimization and comparative study on a novel coupled power cycle featuring isochoric and isothermal processes in internal combustion engine","authors":"Ruizhao Gao ,&nbsp;Kunteng Huang ,&nbsp;Hongrui Li ,&nbsp;Ruikai Zhao ,&nbsp;Ruihua Chen ,&nbsp;Jian Li ,&nbsp;Jun Shen ,&nbsp;Li Zhao","doi":"10.1016/j.enconman.2025.119760","DOIUrl":"10.1016/j.enconman.2025.119760","url":null,"abstract":"<div><div>Developing thermodynamic cycles with higher efficiency is a critical approach to addressing energy conservation, environmental protection, and emission reduction challenges in internal combustion engines. However, existing optimized cycles for internal combustion engines remain constrained by the fundamental limitations of classical thermodynamic cycles, such as the Otto, Diesel, and Brayton cycles, resulting in a bottleneck in cycle performance. Benefit from tension pistons based on advanced flexible materials, isothermal processes in internal combustion engine are flexible. In this paper, a novel cycle called coupled power cycle featuring isochoric and isothermal processes is proposed, increasing the average heat absorption temperature. A thermodynamic model is developed based on the fundamental laws of thermodynamics, and ideal thermal efficiency equation for ideal gas is derived. Results show that the thermal efficiency and the sustainability index are positively correlated to the pressure ratio in compressor and piston combustion chamber. By contrast, the power density will reach the top as a result of the increase in the pressure ratio in compressor while the power density will show the downwards trend with the pressure ratio in piston combustion chamber growing up. If the weights of thermal efficiency and power density are 0.5 and 0.5 differently, optimal performance is achieved at pressure ratios in compressor and piston combustion chamber at 46.00 and 1.56, respectively. Compared to the Diesel and Brayton cycles, the proposed coupled power cycle achieves at least a 30% and 10% improvement in thermal efficiency, respectively. Together with a specific swashplate, the proposed coupled power cycle is expected to realize a significant improvement in the performance of internal combustion engines.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119760"},"PeriodicalIF":9.9,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dairy-farm micro-energy system optimal planning and operation: Driven by dynamic coordination approach to material output and energy demand","authors":"Chen Wang ,&nbsp;Rui Liang ,&nbsp;Kaize Liang ,&nbsp;Honghang Zhang ,&nbsp;Le Zhang ,&nbsp;Hongxu Huang ,&nbsp;Zehua Tang ,&nbsp;Chaoxian Lv","doi":"10.1016/j.enconman.2025.119728","DOIUrl":"10.1016/j.enconman.2025.119728","url":null,"abstract":"<div><div>With the modernization progress of large-scale dairy farms, the demands for eco-friendly operation are becoming increasingly stringent. Some existing farms and those in the early development stages, characterized by underutilized manure, imbalances in electricity supply and demand, and potentially insufficiently considered scalability, are particularly sensitive to these requirements. To address these issues, this paper presents a model characterizing the dynamic coordinated material and energy by analyzing the various cattle growth stages influence, based on specific energy-material requirements in dairy farm. Furthermore, the energy-material cycle of farms is studied to reveal its impacts on the performance of dairy farm micro-energy system(DFMES). Integrating these findings, an optimized planning and operational method for DFMES is proposed, aiming to enhance the initial setup and meet long-term efficiency goals. Case studies from dairy farm in East and Northeast China validate the method, highlighting its effective support for low-carbon operations and efficient energy conversion in dairy farms.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119728"},"PeriodicalIF":9.9,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced Carnot battery for high-efficiency energy storage: Feasibility analysis","authors":"Ce Zhang ,&nbsp;Minxia Li ,&nbsp;Chaobin Dang ,&nbsp;Xun Chen ,&nbsp;Xiuming Li ,&nbsp;Zongwei Han","doi":"10.1016/j.enconman.2025.119754","DOIUrl":"10.1016/j.enconman.2025.119754","url":null,"abstract":"<div><div>The widespread application of renewable energy generation technologies poses a serious challenge to grid stability. It is essential to develop advanced energy storage technologies. The Carnot battery has advantages such as low construction cost and high installation flexibility. However, the low round-trip efficiency of conventional Carnot battery limits its widespread application. In this study, the enhanced Carnot battery is constructed to achieve high-efficiency energy storage, and the performance of various enhanced technologies is discussed. Taking three cities in China as the application sites, the feasibility of the enhanced Carnot battery is analyzed by selecting industrial low-grade waste heat recovery as the application scenario. The results show that the overall performance is optimal when the heat pump module applies the vapor injection technology, and the organic Rankine cycle module applies the dual-pressure evaporation technology. Compared with conventional Carnot battery, the payback period of the enhanced Carnot battery can be shortened by 76.8%, and the levelized cost of storage can be reduced by 26.7%.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119754"},"PeriodicalIF":9.9,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance analysis and optimization of Tesla turbine based on comprehensive operational and structural parameters","authors":"Yang Zhao ,&nbsp;Shiyang Teng ,&nbsp;Dou An ,&nbsp;Huan Xi","doi":"10.1016/j.enconman.2025.119757","DOIUrl":"10.1016/j.enconman.2025.119757","url":null,"abstract":"<div><div>The Tesla turbine shows great potential in small-scale energy utilization systems. Consequently, it is crucial to investigate methods for enhancing the Tesla turbine’s output performance. In response to the current situation of incomplete performance optimization process of Tesla turbine, a comprehensive analysis of its operational and structural parameters is conducted. To identify the optimal parameters and structure of the Tesla turbine in operation, a three-dimensional simulation model is developed, and the computational fluid dynamics method is employed for analysis. Additionally, a prototype of Tesla turbine is designed and manufactured, and experiments are conducted using compressed air to drive the Tesla turbine, thereby validating the reliability of the simulation model. In the study, output power and isentropic efficiency are regarded as optimization objective parameters, while key operational parameters including rotational speed, inlet pressure, and mass flow rate are also considered. The fundamental operating characteristics of the Tesla turbine are initially examined, followed by sequential analyses of the structural parameters including nozzle height, nozzle width, disc spacing, disc thickness, disc diameter, and the number of discs. Through the comprehensive optimization process, the Tesla turbine achieves significant performance improvements, resulting in an output power of 787 W and an efficiency of 32.1 %.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119757"},"PeriodicalIF":9.9,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143703914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aging-aware real-time multi-layer co-optimization approach for hybrid vehicles: across configuration, parameters, and control","authors":"Yunge Zou ,&nbsp;Yalian Yang ,&nbsp;Yuxin Zhang ,&nbsp;Xiaolin Tang","doi":"10.1016/j.enconman.2025.119748","DOIUrl":"10.1016/j.enconman.2025.119748","url":null,"abstract":"<div><div>The powertrain configuration, parameters, and control of hybrid vehicles are intertwined. All of these factors have a significant impact on acceleration, fuel economy, and battery degradation. However, research on the impact of the multi-layer co-optimization of the powertrain physical configuration and control on battery life has been neglected. Therefore, to fill this gap, an innovative aging-aware real-time multi-layer co-optimization method is proposed in this study. In the topology layer, a novel and improved multi-mode multi-gear configuration is proposed, and the performance differences and the intrinsic mechanism of different powertrain types are analyzed quantitatively and qualitatively. In the control layer, an advanced aging-aware fast real-time control strategy (AFRCS) is proposed. In the AFRCS, the offline optimization layer works in combination with Pareto optimization, battery life aging optimization (BLAO), and parallel computation to speed up the computational efficiency. The online mode coordination layer is used for real-time control, which improves the computational efficiency by approximately 20,000 times, and the battery life optimization is in the range of 10.22 %–12.9 %. During real-world driving cycles, the proposed configuration improves the acceleration and the battery life by an average of 50 % and 22.67 %, respectively, compared to a Toyota Prius, and it improves fuel saving by 8.82 % compared to a Honda Accord. Finally, the proposed AFRCS is verified with a hardware-in-the-loop (HIL) experiment. This study provides guidance for the selection, optimization, and real-time control of next-generation electrified transmissions.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119748"},"PeriodicalIF":9.9,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143678188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced energy conversion in a concentrated photovoltaic/thermal system using phase change material as a spectral beam filter","authors":"Yue Yang ,&nbsp;Mostafa M. Abd El-Samie ,&nbsp;Ahmed M.I. Abutalib ,&nbsp;Mohamed I. Hassan Ali ,&nbsp;Lei Zhou","doi":"10.1016/j.enconman.2025.119751","DOIUrl":"10.1016/j.enconman.2025.119751","url":null,"abstract":"<div><div>Thermal stability and spectral absorption challenges still limit concentrated PV/thermal efficiency. This study proposes a novel concentrated PV/thermal system with a hybrid spectral filter integrating a selective liquid filter and phase change material. Innovative numerical procedures are applied to perform 3D multiphysics modeling, uniquely accounting for variations in the optical behavior of phase change materials across phase transitions and wavelengths. Following model validation, performance analysis explores the effects of operating conditions and design parameters on yields, efficiencies, and market feasibility. The findings indicate that integrating phase change material with a selective liquid filter enhances thermal management, stabilizes PV temperatures, and improves spectral absorption, increasing overall yields. The proposed design achieves superior efficiency, with a 49.15 % energy conversion rate and a 240 % improvement over conventional concentrated PV systems.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119751"},"PeriodicalIF":9.9,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143678192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of direct air capture with Allam cycle: Innovative pathway in negative emission technologies","authors":"Alireza Ghorbani ,&nbsp;Ayat Gharehghani ,&nbsp;Jabraeil Ahbabi Saray ,&nbsp;Amin Mahmoudzadeh Andwari ,&nbsp;Tohid N. Borhani","doi":"10.1016/j.enconman.2025.119746","DOIUrl":"10.1016/j.enconman.2025.119746","url":null,"abstract":"<div><div>The advancement of negative emission technologies (NETs) is crucial for addressing climate change by reducing atmospheric carbon dioxide levels. This study presents a comprehensive evaluation of a High Temperature Direct Air Capture (HT-DAC) system integrated with a supercritical CO₂ (S-CO₂) cycle, representing a significant advancement in carbon capture, energy optimization, and NET systems. Given to significant energy demands of HT-DAC, the primary objective of this research is to address the process’s energy intensity by focusing on the development of a more efficient power island. Specifically, this study investigates the energy demands of the Air Separation Unit (ASU) to minimize energy consumption and improve the overall efficiency of the Allam cycle when coupled with the ASU. Additionally, the study examines the thermal integration of the system using pinch analysis to assess the impact of this innovative power island on energy efficiency. Key results indicate that the proposed system is capable of capturing 0.99 million tons of CO₂ per year directly from the air, achieving a capture efficiency of 75 %. The specific energy requirement for the process is initially 3.19 kWh per kg of captured CO₂, which is reduced to 2.21 kWh/kgCO₂ following process optimization and heat integration. Through this optimization, hot and cold utility demands are reduced by 69.7 % and 36.9 %, respectively, while 110.1 MW of heat is recovered through the design of heat exchangers network, resulting in an 9.66 % reduction in overall energy demand compared to the base case. Furthermore, the integration of captured and regenerated CO₂ (135.1 tons per hour with a purity of 98.1 mol%) offers substantial potential for synthetic fuel production and underground storage.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"332 ","pages":"Article 119746"},"PeriodicalIF":9.9,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143678194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}