Energy最新文献

{"title":"Convergence in energy self-sufficiency: the role of renewable energy, fossil fuel rents, energy efficiency and gross domestic product per capita","authors":"Mehmet Pinar","doi":"10.1016/j.energy.2025.136285","DOIUrl":"10.1016/j.energy.2025.136285","url":null,"abstract":"<div><div>Increasing energy self-sufficiency and energy security are essential for countries to promote sustainable development. Analyzing convergence in energy self-sufficiency is crucial for designing policies to address energy security challenges. This paper examines convergence in energy self-sufficiency (measured by the ratio of total primary energy production to total primary energy consumption) across 159 countries from 1993 to 2022. The club convergence algorithm is used to assess whether all countries converge in energy self-sufficiency. The findings indicate that there is no overall convergence across all countries, but distinct convergence clubs exist. Additionally, the analysis reveals varying numbers of convergence clubs in energy self-sufficiency across different geographical regions. Furthermore, conditional beta convergence analyses are conducted using system generalized methods of moments (GMM) to identify the key determinants of energy self-sufficiency. A Probit model is also employed to examine the factors that increase the likelihood of belonging to a high-energy self-sufficiency club. The results suggest that countries with higher fossil fuel rents, greater renewable energy production, and improved energy efficiency tend to increase their energy self-sufficiency and belong to the final convergence club with higher energy self-sufficiency.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136285"},"PeriodicalIF":9.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864201","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":"Fatigue analysis of wind turbine and load reduction through wind-farm-level yaw control","authors":"Yize Wang,&nbsp;Zhenqing Liu","doi":"10.1016/j.energy.2025.136266","DOIUrl":"10.1016/j.energy.2025.136266","url":null,"abstract":"<div><div>Wind-farm-level yaw-control-based power optimization can improve the total power output. However, previous related studies have rarely considered wind turbine fatigue loads during power optimization. Consequently, this study proposes a novel farm-level yaw control optimization algorithm that can maximize the total power output and simultaneously minimize the wind turbine fatigue loads. To implement this, the structural dynamics of a wind turbine under different wind speeds, turbulence intensities, and yaw angles are calculated first. The out-of-plane fatigue loads at the blade root are positively correlated with the yaw angle, and the out-of-plane fatigue loads at the yaw bearing and tower base are negatively correlated with the yaw angle. Subsequently, accurate meta models are trained to predict the wind turbine fatigue loads. They perform well, with the errors of the out-of-plane meta models all being smaller than 1.0 %. Finally, the yaw angles of the wind turbines are optimized via the differential evolution algorithm. The numerical results indicate that for the examined wind farms, the proposed optimization method can increase the total power output by at least 6.4 % and at most 7.8 %; moreover, it can reduce the added wind turbine fatigue loads caused by power optimization by at least 23.53 % and 52.25 % at most.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136266"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143864197","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":"The flame structure and combustion dynamics in micro-mixing combustion of hydrogen-rich syngas with air","authors":"Dengke Chen ,&nbsp;Penghua Qiu ,&nbsp;Chang Liu ,&nbsp;Wentong Wang ,&nbsp;Rui Sun ,&nbsp;Yijun Zhao ,&nbsp;Linyao Zhang ,&nbsp;Chang Xing ,&nbsp;Li Liu","doi":"10.1016/j.energy.2025.136282","DOIUrl":"10.1016/j.energy.2025.136282","url":null,"abstract":"<div><div>Micro-mixing (MM) combustion technology demonstrates remarkable NOx reduction capability in gas turbines. As for hydrogen-rich syngas with typical heating value, the experimental studies are carried out at different equivalence ratio (<em>φ</em>) of 0.380, 0.403, 0.426, 0.450, 0.474 and 0.499 and different nozzle outlet mixture velocity (<em>v</em>) of 32, 43, 54,64 and 75 m/s. An in-depth discussions on flame structure, combustion dynamics, and pollutant emissions is conducted. The result shows that in the operation range, no flashback or combustion oscillation occurred in actual experiments of the combined MM nozzles. With the increase of <em>φ</em> or decrease of <em>v</em>, the overall OH signal intensity and the anchoring ability of the flames become stronger, the heat release rate and temperature distribution uniformity would be enhanced, the degree of flame fluctuation decreases. NO emission increases rapidly with the increase of <em>φ</em>, which is consistent with the generation characteristics of thermal type NO, but under test conditions, they are not higher than 15 μL/L at 15 %O₂. The increase of <em>v</em> is beneficial for reducing NO emission, attributed to the shortened residence time of gas.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136282"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869336","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":"Influence of blockage ratio and length-to-diameter ratio on explosion dynamics of DME/H2 blended gas in semi-open space","authors":"Yu Ma ,&nbsp;Tao Fan ,&nbsp;Yijun Li ,&nbsp;Qi Zhang ,&nbsp;Qian Zhao ,&nbsp;Yuchun Zhang","doi":"10.1016/j.energy.2025.136258","DOIUrl":"10.1016/j.energy.2025.136258","url":null,"abstract":"<div><div>This study systematically investigates the influence of obstacle blockage ratio (BR = 0–0.75) and pipeline length-to-diameter (L/D = 45–90) ratio on explosion dynamics in dimethyl ether/hydrogen (DME/H₂) blended gas. The results indicate that increasing BR enhances flame turbulence, which intensifies combustion reactions and accelerates flame propagation. Consequently, there is a significant rise in the maximum explosion overpressure (<em>P</em>_max) and a reduction in the time to reach <em>P</em>_max. Specifically, <em>P</em>_max increases the most at BR = 0.55 with 204 % and the time to reach <em>P</em>_max shortens the most at BR = 0.35 with 13.3 % compared to unobstructed condition. However, at the higher blockage ratio of BR = 0.75, the throttling effect becomes dominant, resulting in a decrease in <em>P</em>_max and an extended time to reach <em>P</em>_max. Additionally, increasing the L/D ratio enhances the turbulence effect generated during the flame propagation, resulting in the formation of more small-scale vortex structures at the flame front. This promotes the mixing of unburned gas with the flame front, thereby increasing the combustion rate and peak overpressure, while shortening the time to reach <em>P</em>_max by 7.95–41.4 %. Notably, neither BR nor L/D ratio significantly affected peak flame temperatures.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136258"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874971","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":"Optimized combustion characteristics in a top-blown converter utilizing a swirling-flow post-combustion oxygen lance","authors":"Qichang Liu ,&nbsp;Jian Wang ,&nbsp;Guangqiang Liu ,&nbsp;Yuanxin Liu","doi":"10.1016/j.energy.2025.136082","DOIUrl":"10.1016/j.energy.2025.136082","url":null,"abstract":"<div><div>The steel industry is confronted with urgent challenges in the Post-Combustion (PC) phase of converters, such as reduced combustion efficiency, inefficient energy utilization, and high CO emissions. To address these issues, this study presents an innovative technical approach: integrating secondary combustion with swirl composite injection smelting. By leveraging the Swirl-Flow Post-Combustion Oxygen Lance (SFPCL), a comprehensive three-dimensional numerical model of the combustion zone in a top-blown converter has been developed. Using Computational Fluid Dynamics (CFD) techniques combined with a turbulence-chemical reaction coupling model, this study investigates the velocity field, temperature field, component distribution, and Post-Combustion Ratio (PCR) related to the SFPCL. The results indicate that the swirling jet ejected from the primary oxygen nozzle significantly enhances the jet's independent characteristics and effectively reduces the coupling between the primary and secondary jets. The secondary jet's impact area increases, and its impact velocity at H = 1.25 m rises by 39.12 %. As the swirl angle was incremented to 15°, the CO concentration within the converter space diminished by 37.5 %, whereas the CO₂ concentration escalated by 42.86 %. Furthermore, the combustion temperature soared by 215K, and the combustion zone area expanded by 36.67 %. At the converter outlet, notable changes were observed: the CO concentration decreased by 2.56 %, the CO₂ concentration rose by 2.7 %, and the PCR improved by 3.7 %. These findings underscore that increasing the swirl angle can bolster post-combustion efficiency and mitigate CO emissions. This study offers fresh theoretical underpinnings and practical insights for developing high-efficiency, energy-saving converter steelmaking technologies.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136082"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876631","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":"An Informer-BiGRU-temporal attention multi-step wind speed prediction model based on spatial-temporal dimension denoising and combined VMD decomposition","authors":"Zhengze Fu ,&nbsp;Hongliang Qian ,&nbsp;Wei Wei ,&nbsp;Xuanxuan Chu ,&nbsp;Fan Yang ,&nbsp;Chengchao Guo ,&nbsp;Fuming Wang","doi":"10.1016/j.energy.2025.136265","DOIUrl":"10.1016/j.energy.2025.136265","url":null,"abstract":"<div><div>Accurate wind speed prediction is crucial for optimizing renewable energy utilization and enhancing operational safety in wind farms. However, existing methods face challenges due to data noise, mode mixing in decomposition, and limited model adaptability for multi-step forecasting. This paper proposes a novel hybrid framework (HPMTC-CVMD-IBTA) integrating three innovations: (1) A spatial-temporal denoising method (HPMTC) combining high-order polynomial fitting with M-estimator correction and temporal clustering to preserve signal integrity while removing noise; (2) A decomposition-optimization approach (CVMD) that adaptively weights variational mode decomposition (VMD) components via convolutional neural networks, reducing reconstruction errors compared to traditional methods; and (3) An Informer-BiGRU-Temporal Attention (IBTA) model that leverages multi-variable dependencies and long-sequence patterns through bidirectional gated units and attention mechanisms. Experiments on real-world wind farm datasets (Guangdong and Gansu, China) demonstrate the framework's superiority: It achieves over 99 % prediction accuracy (R²), reduces MAE by 15–40 % against benchmarks (e.g., LSTM, BiGRU), and improves multi-step forecasting robustness across seasons. The proposed system addresses critical limitations in noise sensitivity, decomposition instability, and temporal feature decay, offering a reliable solution for energy management and disaster prevention.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136265"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876636","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":"The effect of straw management on energy use efficiency, food security, and environmental costs","authors":"Deqiang Zhao ,&nbsp;Yiping Xu ,&nbsp;Zhitong Wang ,&nbsp;Pinshang Xu ,&nbsp;Zexue Li ,&nbsp;Weibao Yu ,&nbsp;Zixi Liu ,&nbsp;Yuan Wen","doi":"10.1016/j.energy.2025.136261","DOIUrl":"10.1016/j.energy.2025.136261","url":null,"abstract":"<div><div>Straw return is widely acknowledged as an effective strategy for reducing greenhouse gas emissions and enhancing energy use efficiency, but its effectiveness depends on the specific management approach. We conducted a three-year field experiment to investigate the effects of five straw management strategies on crop yield, soil organic carbon (SOC), carbon footprint (CF), energy use efficiency, and economic benefits. The strategies included straw removal, straw mulching, straw incorporation, deep-ploughed straw incorporation and deep-injected straw incorporation. The findings show that although straw return increased CF compared to straw removal, this effect can be offset by increased SOC sequestration. Straw return also increase energy consumption and costs during agricultural operations, but higher crop productivity creates higher energy use efficiency and net benefits. Compared to others, deep-injected straw incorporation demonstrated a concurrent increase in CF and SOC sequestration (42.4 Mg ha⁻¹ year⁻¹), while also achieving the highest crop yields and farmer income. Straw mulching exhibited the lowest energy consumption and CF but led to a 7.3 % reduction in wheat yield. In conclusion, deep-injected straw incorporation offers a promising approach to achieving the dual goals of enhancing crop productivity and mitigating environmental impacts.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136261"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143878820","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":"Migration characteristics and prediction of high temperature points in coal spontaneous combustion","authors":"Changkui Lei ,&nbsp;Yaoqian Zhu ,&nbsp;Quanchao Feng ,&nbsp;Li Ma ,&nbsp;Jingyu Zhao ,&nbsp;Chuanbo Cui ,&nbsp;Cunbao Deng","doi":"10.1016/j.energy.2025.136288","DOIUrl":"10.1016/j.energy.2025.136288","url":null,"abstract":"<div><div>The determination and quantitative prediction of the high temperature points of coal spontaneous combustion in the gob is crucial for preventing coal spontaneous combustion fires. In this study, a large scale 2-ton experimental furnace was used to investigate the spontaneous oxidation process of coal and to explore the migration characteristics of the high temperature points of coal spontaneous combustion within the experimental furnace. Furthermore, a Bayesian-optimized K-nearest neighbors (BO-KNN) model for the quantitative prediction of coal spontaneous combustion temperature was established, and the model was compared with support vector regression (SVR) and partial least squares (PLS) models. The accuracy and robustness of the BO-KNN model were verified using in-situ monitoring data. The results show that the mean absolute percentage errors (MAPE) of the KNN, SVR, and PLS models during the testing stage were 2.065%, 6.893%, and 7.909%, respectively, and they reduced to 1.355%, 2.656%, and 7.503% after Bayesian optimization, respectively, indicating that the KNN model outperforms both the SVR and PLS models in terms of prediction accuracy. Moreover, the BO algorithm significantly enhances the predictive performance of the SVR model, while the improvement in the PLS model is minimal. The overall prediction performance of the PLS model is the lowest, suggesting its difficulty in capturing the nonlinear relationship between the gas products and coal temperature of coal spontaneous combustion. To further validate the practical performance of the KNN method, a long-term in-situ observation was conducted in the gob of the fully mechanized caving face at the Dafosi Coal Mine in Binzhou City, Shaanxi Province, China. Based on the in-situ data, KNN and BO-KNN models were developed, which demonstrated MAE &lt; 1.033 °C, MAPE &lt; 3.190%, and R² &gt; 0.912 during the training stage, and MAE &lt; 0.902 °C, MAPE &lt; 2.826%, R² &gt; 0.916 during the testing stage. These results confirm the high accuracy, strong generalization ability, and robust reliability of the KNN algorithm, making it highly suitable for the precise prediction of coal spontaneous combustion temperatures.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136288"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876633","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":"A feature optimized attention transformer with kinetic information capture and weighted robust Z-score for industrial NOx emission forecasting","authors":"Jian Long ,&nbsp;Siyu Jiang ,&nbsp;Luyao Wang ,&nbsp;Jiazi Zhai ,&nbsp;Feng Zhang ,&nbsp;Liang Zhao","doi":"10.1016/j.energy.2025.136276","DOIUrl":"10.1016/j.energy.2025.136276","url":null,"abstract":"<div><div>Establishing an accurate and stable NO_x concentration prediction model is of great significance for pollution control in refineries and achieving carbon neutrality goals. The actual industrial denitrification process exhibits high nonlinearity, strong coupling, and multivariable dynamic characteristics, which makes modeling difficult. This paper proposes a novel model based on Transformer designed to uncover the potential dynamic relationships between variables. First, for unstable industrial data, a Weighted Robust Z-score (WRZ) method is employed, which assigns weights to data points and uses weighted median and interquartile range to replace traditional mean and standard deviation for calculating deviations of data points. Second, to address the complex dynamic characteristics of the data, an Enhanced Pooling Feature Module (EPFM) is proposed, combining weighted pooling and average pooling to optimize feature extraction. Embedded in Transformer, EPFM adjusts attention, highlighting key features. Finally, Attention scores visualization explicitly clarifies variable interaction mechanisms, enhancing model interpretability. Experiments on four chemical datasets validated the proposed model's effectiveness. In the catalytic cracking regeneration flue gas denitrification dataset, the proposed method has RMSE values of 0.8 and 0.922, and R² values of 0.993 and 0.956, outperforming others. It offers an effective way to boost industrial denitrification efficiency and reduce NO_x emissions.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136276"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143878822","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":"Comparative analysis of a CCHP system based on municipal solid waste (MSW) gasification using micro gas turbine and internal combustion engine: Energy, exergy, economic, and environmental (4E) perspectives","authors":"Behzad Omidi Kashani ,&nbsp;Rahim Khoshbakhti Saray ,&nbsp;Reza Kheiri","doi":"10.1016/j.energy.2025.136004","DOIUrl":"10.1016/j.energy.2025.136004","url":null,"abstract":"<div><div>This paper introduces a thermo-economic model for a combined cooling, heating, and power (CCHP) system using municipal solid waste (MSW) as feedstock, designed to operate without external energy sources. Two configurations are evaluated: one with a micro gas turbine-based (MGTB) generator and another with an internal combustion engine-based (ICEB) system. Syngas undergoes post-treatment and is used for power generation, steam and hot water production, and heating air for processes like the MSW dryer. The MGTB system achieves energy efficiencies of 41.03 % (summer) and 42.18 % (cold season), while the ICEB system achieves 61.37 % and 67.77 %, respectively. Exergy efficiencies for the MGTB system are 9.52 % and 10.87 %, and for the ICEB system, 31.12 % and 29.93 %, respectively. The annual cost per MWh for the MGTB system is $10.38, compared to $8.69 for the ICEB system. CO₂ emissions for the MGTB system are 9548 and 8882 tons per year (hot and winter), while the ICEB system emits 7488 and 7055 tons per year, respectively. The ICEB system's higher exergy efficiency leads to lower exergy loss, a 270 % increase in the environmental improvement index, and a 26 % annual increase in the sustainability index compared to the MGTB system.</div></div>","PeriodicalId":11647,"journal":{"name":"Energy","volume":"326 ","pages":"Article 136004"},"PeriodicalIF":9.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859959","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}