Energies最新文献

{"title":"Enabling High-Degree-of-Freedom Thermal Engineering Calculations via Lightweight Machine Learning","authors":"Yajing Tian, Yuyang Wang, Shasha Yin, Jia Lu, Yu Hu","doi":"10.3390/en17163916","DOIUrl":"https://doi.org/10.3390/en17163916","url":null,"abstract":"U-tube steam generators (UTSGs) are crucial in nuclear power plants, serving as the interface between the primary and secondary coolant loops. UTSGs ensure efficient heat exchange, operational stability, and safety, directly impacting the plant’s efficiency and reliability. Existing UTSG models have fixed structures, which can only be used when certain parameters are given as model input. Such constraints hinder their ability to accommodate the diverse operating conditions, where input and output parameters can vary significantly. To address this challenge, we propose a machine learning-based method for developing a high-degree-of-freedom UTSG thermal model. The most notable feature of this approach is its capacity to flexibly interchange input and output parameters. By adopting comprehensive parameter sensitivity analysis, the most efficient method for training dataset generation is determined. Leveraging a lightweight machine learning method, the prediction accuracy for all UTSG parameters is improved to within 2.1%. The flexibility of the proposed machine learning approach ensures that the UTSG model can accommodate any type of parameter input without extensive reconfiguration of the model structure, thereby enhancing its applicability and robustness in real-world applications.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141927509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Quantitative Evaluation Method Based on Single-Ended Information Protection Adaptability Considering Distributed Generator Access","authors":"Weichen Liang, Yiwei Zhao, Xuan Li, Guomin Luo, Jin Zong, Mengyu Wu, Bo Liu","doi":"10.3390/en17163907","DOIUrl":"https://doi.org/10.3390/en17163907","url":null,"abstract":"A high proportion of distributed generators (DGs) connected to the distribution network causes a significant change in the normal and fault currents of the system as well as in the linearization of the characteristics. It is difficult to adapt to conventional protection. This paper theoretically analyzes the possible impact of fault current characteristics on traditional protection based on single-ended informativeness after connecting to DGs. From the perspective of protection action, the evaluation index system of DG protection is established by considering the maximum short-circuit current output from DG. Combined with the relay protection requirements, the calculation method of evaluation indexes is given concerning the protection characteristics and expert experience. An analytic hierarchy process (AHP) and a CRITIC combination assignment method based on the principle of minimum information identification are proposed. The scores of different types of protection before and after DG access are calculated using the proposed methodology employing a typical distribution network example. The proposed method can quantitatively obtain the distribution network protection adaptability boundary. In the actual calculation example selected in this paper, a DG can reasonably improve the adaptability of the three-stage current protection when it increases the current amplitude at a penetration rate of 50%; the DG needs to adjust the three-stage current protection rectification value when it decreases the current amplitude at a penetration rate of 20%; and adaptive overcurrent protection and inverse time limit current protection need to be adjusted when the penetration rate of DG is 50%. Compared with the traditional protection evaluation method, the method adopted in this paper can intuitively derive the weak link between protection handling faults after DG access as well as the appropriate capacity of DG to improve protection performance. It can provide a powerful reference for the optimization of protection schemes after the high percentage of DG access.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141926504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Life Cycle Assessment of Piezoelectric Devices Implemented in Wind Turbine Condition Monitoring Systems","authors":"Rabie Aloui, R. Gaha, Barbara Lafarge, B. Celik, Caroline Verdari","doi":"10.3390/en17163928","DOIUrl":"https://doi.org/10.3390/en17163928","url":null,"abstract":"Assessing the vibration signature produced by a rotating component of the wind turbine enables the identification of operational conditions and the detection of potential faults at an early stage. The main purpose is to enhance the sustainability of wind turbines while increasing the lifespan and uptime of their operational systems. This vibration analysis is based on the processing of the signal provided by sensors, which often incorporates piezoelectric transducers. This paper evaluates the consequences of employing piezoelectric sensors used for vibration measurement on electrical machines integrated into wind turbines by conducting a life cycle assessment (LCA). The widespread use of piezoelectric materials is due to their high sensitivity to vibrations, although their selection is also influenced by regulatory restrictions. This research focuses on the environmental impact of piezoelectric accelerometers used commonly in condition monitoring systems. The collected literature data on the manufacturing processes are inputted into the LCA model which is powered by the Ecoinvent 3 database. The impact assessment is carried out using the European ILCD 2011 Midpoint+ method by calculating the unique scores of the selected impact categories. The results are presented and discussed in terms of environmental indicators, as well as ecological recommendations on the design.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141928185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FTIR Analysis for Determining Stability of Methanol–HVO Blends for Non-Road Engine Application","authors":"F. Balogun, H. Wang-Alho, K. Sirviö, M. Mikulski","doi":"10.3390/en17163921","DOIUrl":"https://doi.org/10.3390/en17163921","url":null,"abstract":"The Green Deal targets, along with tightening emissions legislation, foster research on alternative propulsion systems. In non-road mobile machinery (NRMM), these efforts largely rally around sustainable fuels while keeping the benefits of energy security (multi-fueling) high. In this context, the blends of Hydrogenated Vegetable Oil (HVO) and Methanol (MEOH) are amongst the most promising yet under-researched alternatives and, as such, need dedicated methods for determining their suitability in engine applications. In this paper, we evaluate the feasibility of Fourier transform infrared (FTIR) analytics for determining the stability of MEOH-HVO mixtures. The research considers temperature effects during storage by conditioning the test samples at −20 °C and +20 °C. The stability of the blends and different co-solvents is analysed after six weeks, and FTIR spectra are used to identify the chemical bonds. From FTIR analysis, blending MEOH20 with 1-dodecanol results in stable homogenous alkyl-ether fuels, while the MEOH20 blend with methyl-butyrate results in ester fuels. There are observable differences in the blend samples according to their storage temperatures. In conclusion, both fuel blend samples formed different fuel types, which are stable and homogenous at room temperature, posing great potential for their applicability in different NRMM types.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141925468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Bi-Level Reactive Power Optimization for Wind Clusters Integrating the Power Grid While Considering the Reactive Capability","authors":"Xiping Ma, Wenxi Zhen, Rui Xu, Xiaoyang Dong, Yaxin Li","doi":"10.3390/en17163910","DOIUrl":"https://doi.org/10.3390/en17163910","url":null,"abstract":"With the integration of large-scale wind power clusters into the power system, wind farms play a crucial role in grid reactive power regulation. However, the range of its reactive power remains uncertain, posing challenges in formulating a viable program for regulating reactive power to ensure the safe and cost-effective operation of the power system. Based on this, this paper develops a bi-level reactive power optimization for wind clusters integrating the power grid while considering the reactive capability. Firstly, this paper carries out a refined analysis of the wind power clusters, taking into account the characteristics of different areas to estimate the exact value of the reactive power capability in wind power clusters. Secondly, a bi-level reactive power optimization model is established. The upper-layer optimization aims to minimize active losses and voltage deviation in power system operation, while the lower-layer optimization focuses on maximizing reactive power margin utilization in wind farms. To solve this bi-level optimization model, an improved artificial fish swarm algorithm (AFSA) is employed, which decouples real variables and integer variables to enhance the optimization ability of the algorithm. Finally, the effectiveness of our proposed optimization strategy and algorithm is validated through the simulation results.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141928184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on Gas Channeling Identification Using the Fuzzy Comprehensive Evaluation Method","authors":"Yang Liu, Mingqiang Hao, Ran Bi, Chaoliang Bian, Xiaoqing Wang","doi":"10.3390/en17163908","DOIUrl":"https://doi.org/10.3390/en17163908","url":null,"abstract":"With the development of the petroleum industry and advancements in technology, gas injection techniques have gradually matured and become an important means to enhance oil recovery in reservoir development. Gas channeling is a major challenge in the process of gas injection development. The presence of gas channeling can lead to a decrease in the swept volume of gas flooding, severely affecting the effectiveness of gas injection development. This paper focuses on low-permeability reservoirs, comprehensively analyzing the development characteristics of low-permeability reservoirs and the dynamic characteristics of gas flooding production. It selects and evaluates indicators for assessing the development degree of gas channeling and establishes a fuzzy comprehensive evaluation method for evaluating gas channeling in the gas injection development of low-permeability reservoirs. Based on the evaluation values derived from the fuzzy comprehensive evaluation, it classifies the development levels of gas channeling. Application in oilfield cases shows that the evaluation results of this method are generally consistent with the dynamic response of production data, with high evaluation accuracy. This provides strong support for implementing gas channeling prevention and control measures on site and improving the effectiveness of gas injection development.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Importance of Public Sources of Financing the Development of Renewable Energy in Agriculture, Using the Example of Eastern Poland","authors":"R. Przygodzka, A. Badora, K. Kud, Jarosław Mioduszewski, M. Woźniak, Artur Stec","doi":"10.3390/en17153682","DOIUrl":"https://doi.org/10.3390/en17153682","url":null,"abstract":"This article addresses the issue of public support for the development of renewable energy and the assessment of this support from the perspective of farmers in Eastern Poland. Since it is a region characterized by a relatively high share of agriculture in the economy, a diversified structure of this sector, and at the same time, a region with a relatively high level of energy poverty, it can be considered a good example for illustrating the research problem. To achieve the goal, surveys were carried out covering 519 farms. Upon the consideration of a literature review and the research results of other authors, the collected opinions of the owners of these farms regarding the motivators encouraging them to invest in renewable energy technologies and the assessment of the role of the state in supporting energy transformation allowed for the formulation of conclusions. The research results indicate that renewable energy technologies are present in 47% of the surveyed farms, while in 36% of them, investments were financed from farmers’ own funds. This means that the possibility of obtaining support from public funds is not a necessary condition for implementing renewable energy investments.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141799198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural and Compositional Analysis of CZTSSe Thin Films by Varying S/(S+Se) Ratio","authors":"M. Zaki, Florinel Sava, I. Simandan, C. Mihai, Alin Velea","doi":"10.3390/en17153684","DOIUrl":"https://doi.org/10.3390/en17153684","url":null,"abstract":"The development of kesterite (Cu2ZnSn(S,Se)4, CZTSSe) thin films for photovoltaic applications is highly necessary, given their composition of Earth-abundant, environmentally friendly elements and their compatibility with established photovoltaic technologies. This study presents a novel synthesis approach for CZTSSe films with varied S/(S+Se) ratios, ranging from 0.83 to 0.44, by a two-step magnetron sputtering deposition/annealing process. The first step consists in an initial deposition of stacked Mo/SnS2/Cu layers, which, upon thermal treatment in a sulfur atmosphere, were transformed into Cu2SnS3 (CTS) films. In the second step, further deposition of ZnSe and subsequent annealing in a tin and selenium atmosphere resulted in the formation of a CZTSSe phase. These processes were optimized to fabricate high-quality and single-phase CZTSSe films, thereby mitigating the formation of secondary phases. Characterization techniques, including scanning electron microscopy, demonstrated a clear correlation between decreased S/(S+Se) ratios and enhanced film densification and grain size. Moreover, grazing incidence X-ray diffraction and Raman spectroscopy confirmed a compositional and structural transition from close to CZTS to nearly a CZTSe phase as the S/(S+Se) ratios decreased. This study advances kesterite-based solar cell technology by enhancing the structural properties and crystallinity of the absorber layer, necessary for improving photovoltaic performance.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141800360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct CO2 Hydrogenation over Bifunctional Catalysts to Produce Dimethyl Ether—A Review","authors":"Samira Ebrahimian, Sankar Bhattacharya","doi":"10.3390/en17153701","DOIUrl":"https://doi.org/10.3390/en17153701","url":null,"abstract":"Hydrogenation of CO2 represents a promising pathway for converting it into valuable hydrocarbons and clean fuels like dimethyl ether (DME). Despite significant research, several challenges persist, including a limited understanding of reaction mechanisms, thermodynamics, the necessity for catalyst design to enhance DME selectivity, and issues related to catalyst deactivation. The paper provides a comprehensive overview of recent studies from 2012 to 2023, covering various aspects of CO2 hydrogenation to methanol and DME. This review primarily focuses on advancing the development of efficient, selective, and stable innovative catalysts for this purpose. Recent investigations that have extensively explored heterogeneous catalysts for CO2 hydrogenation were summarized. A notable focus is on Cu-based catalysts modified with promoters such as Zn, Zr, Fe, etc. Additionally, this context delves into thermodynamic considerations, the impact of reaction variables, reaction mechanisms, reactor configurations, and recent technological advancements, such as 3D-printed catalysts. Furthermore, the paper examines the influence of different parameters on catalyst deactivation. The review offers insights into direct CO2 hydrogenation to DME and proposes paths for future investigation, aiming to address current challenges and advance the field.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141800789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Analysis of Greenhouse Gas Emissions in Electrolysis for Certifying Clean Hydrogen","authors":"Yunji Kim, Inhong Min, Jieun Lee, Heena Yang","doi":"10.3390/en17153698","DOIUrl":"https://doi.org/10.3390/en17153698","url":null,"abstract":"The drive for carbon neutrality has led to legislative measures targeting reduced greenhouse gas emissions across the transportation, construction, and industry sectors. Renewable energy sources, especially solar and wind power, play a pivotal role in this transition. However, their intermittent nature necessitates effective storage solutions. Green hydrogen and ammonia have gained attention for their potential to store renewable energy while producing minimal emissions. Despite their theoretical promise of zero greenhouse gas emissions during production, real-world emissions vary based on system configurations and lifecycle assessments, highlighting the need for detailed evaluations of their environmental impact. Therefore, in this study, calculations were performed for the actual amount of produced greenhouse gas emissions that are associated with the production of green hydrogen using electrolysis, from raw material extraction and processing to hydrogen production, with these assessed from well-to-gate emission estimates. Emissions were also evaluated based on various types of renewable energy sources in South Korea, as well as hydrogen production volumes, capacities, and types. Using these data, the following factors were examined in this study: carbon dioxide emissions from the manufacturing stage of electrolysis equipment production, the correlation between materials and carbon dioxide emissions, and process emissions. Current grades of clean hydrogen were verified, and the greenhouse gas reduction effects of green hydrogen were confirmed. These findings are significant against the backdrop of a country such as South Korea, where the proportion of renewable energy in total electricity production is very low at 5.51%. Based on the domestic greenhouse gas emission efficiency standard of 55 kWh/kgH2, it was found that producing 1 kg of hydrogen emits 0.076 kg of carbon dioxide for hydropower, 0.283 kg for wind power, and 0.924 kg for solar power. The carbon dioxide emissions for AWE and PEM stacks were 8434 kg CO2 and 3695 kg CO2, respectively, demonstrating that an alkaline water electrolysis (AWE) system emits about 2.3 times more greenhouse gasses than a proton exchange membrane (PEM) system. This indicates that the total carbon dioxide emissions of green hydrogen are significantly influenced by the type of renewable energy and the type of electrolysis used.","PeriodicalId":11557,"journal":{"name":"Energies","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141800875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}