Journal Description
Energies
Energies
is a peer-reviewed, open access journal of related scientific research, technology development, engineering policy, and management studies related to the general field of energy, from technologies of energy supply, conversion, dispatch, and final use to the physical and chemical processes behind such technologies. Energies is published semimonthly online by MDPI. The European Biomass Industry Association (EUBIA), Association of European Renewable Energy Research Centres (EUREC), Institute of Energy and Fuel Processing Technology (ITPE), International Society for Porous Media (InterPore), CYTED and others are affiliated with Energies and their members receive a discount on the article processing charges.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), Ei Compendex, RePEc, Inspec, CAPlus / SciFinder, and other databases.
- Journal Rank: CiteScore - Q1 (Engineering (miscellaneous))
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 16.1 days after submission; acceptance to publication is undertaken in 3.3 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
- Sections: published in 41 topical sections.
- Testimonials: See what our editors and authors say about Energies.
- Companion journals for Energies include: Fuels, Gases, Nanoenergy Advances and Solar.
Impact Factor:
3.2 (2022);
5-Year Impact Factor:
3.3 (2022)
Latest Articles
Research on the EMA Control Method Based on Transmission Error Compensation
Energies 2024, 17(11), 2528; https://doi.org/10.3390/en17112528 - 23 May 2024
Abstract
This research investigates the impact of nonlinear clearance factors on position tracking accuracy in the servo drive system of a harmonic reducer. The study introduces a technique for modeling and compensating for transmission errors, thereby improving position tracking accuracy through online compensation combined
[...] Read more.
This research investigates the impact of nonlinear clearance factors on position tracking accuracy in the servo drive system of a harmonic reducer. The study introduces a technique for modeling and compensating for transmission errors, thereby improving position tracking accuracy through online compensation combined with an auto-disturbance rejection controller. Initially, the mathematical model of the permanent magnet synchronous motor is outlined, and the current loop and speed loop control models are derived. Subsequently, an electromechanical actuator (EMA) simulation model with clearance is established, and detailed simulation analysis is conducted to verify the impact of clearance on tracking accuracy. A model for online compensation of transmission errors is then developed. Following the principles of active disturbance rejection control (ADRC), a second-order ADRC is formulated for real-time compensation of transmission errors in EMA position mode. Finally, through no-load and load experiments, the change in position tracking error with and without transmission error compensation is compared and analyzed. The results demonstrate that utilizing automatic disturbance rejection control with transmission error compensation achieves the highest position tracking accuracy. Compared to the proportion integration differentiation (PID) control method, the root mean square of position tracking error is reduced by approximately 12.8% and 17.3% under no-load and load conditions, respectively. By compensating for position errors online, the accuracy of the EMA position can be improved.
Full article
(This article belongs to the Section F: Electrical Engineering)
Open AccessArticle
A Study on the Plugging Effect of Different Plugging Agent Combinations during CO2 Flooding in Heterogeneous Reservoirs
by
Xuetong Zhang, Wenjuan Ji, Haiyang Yu, Yilin Li, Fei Yan, Weiqiang Song, Xinrui Jiang and Hongbao Wang
Energies 2024, 17(11), 2527; https://doi.org/10.3390/en17112527 - 23 May 2024
Abstract
Gas channeling control is key to improving CO2-flooding efficiency. A traditional plugging system has disadvantages, such as poor adaptability and stability, leading to the poor plugging effect of CO2 channeling in heterogeneous reservoirs and difficulty in controlling the subsequent CO
[...] Read more.
Gas channeling control is key to improving CO2-flooding efficiency. A traditional plugging system has disadvantages, such as poor adaptability and stability, leading to the poor plugging effect of CO2 channeling in heterogeneous reservoirs and difficulty in controlling the subsequent CO2 injection pressure. To achieve a significant plugging effect and effectively control the subsequent CO2 injection pressure, a heterogeneous physical model of gas channeling in a horizontal well was established, and plugging experiments were conducted using four different combinations of plugging agents during CO2 flooding. Three evaluation parameters were defined, including the temperature field variation coefficient (TFVC), medium-permeability diversion rate (MPDR), and subsequent injection pressure coefficient (SIPC). The plugging effect of different combinations of plugging agents during CO2 flooding in heterogeneous reservoirs was analyzed. The results show that the plugging effect after using a combination of plugging agents was significantly better than after using a single plugging agent, and different plugging agent combinations had distinct characteristics. The strong–medium–weak (S-M-W) combination had the best MPDR for subsequent CO2 flooding, but the SIPC was the highest. The strong–weak–strong–weak (S-W-S-W) and weak–strong–weak–strong (W-S-W-S) combinations could effectively control the SIPC. These results indicate that plugging using the S-W-S-W and W-S-W-S combinations can achieve an effective plugging effect and reasonably control the subsequent CO2 injection pressure. This work provides a personalized design scheme for effective gas channeling control and maintenance of appropriate injection pressure during CO2 flooding in heterogeneous reservoirs.
Full article
(This article belongs to the Section H: Geo-Energy)
►▼
Show Figures
Figure 1
Open AccessArticle
Assessment of Refracturing Potential of Low Permeability Reservoirs Based on Different Development Approaches
by
Jingchun Zhang, Ming Gao, Jingfeng Dong, Tianxi Yu, Kebao Ding and Yan Liu
Energies 2024, 17(11), 2526; https://doi.org/10.3390/en17112526 - 23 May 2024
Abstract
The technique of refracturing is an effective method to solve the rapid decline in oil well production caused by factors such as severe reservoir energy loss and fracture failure after the initial hydraulic fracturing of low-permeability reservoirs. The key to designing refracturing lies
[...] Read more.
The technique of refracturing is an effective method to solve the rapid decline in oil well production caused by factors such as severe reservoir energy loss and fracture failure after the initial hydraulic fracturing of low-permeability reservoirs. The key to designing refracturing lies in establishing a model for evaluating the potential fracturing layers. Based on the geological characteristics of the low-permeability conglomerate reservoir in the Lower Wuerhe area of the Eig District of the Xinjiang Oilfield, this paper studies the influence of different development approaches on the distribution pattern of remaining oil in the reservoir. A coupled model of remaining oil distribution and the in situ stress field is established and discusses the characteristics of the four-dimensional in situ stress field under different development modes. This paper analyzes the influence of geological factors and well network factors on the distribution of residual oil, and analyzes the influence of various factors, such as reservoir properties and injection and extraction parameters, on ground stress. Based on the residual oil distribution and ground stress changes, an evaluation method for screening potential fractured layers in reservoirs with different development modes (water injection development and depletion development) is developed.
Full article
(This article belongs to the Special Issue Subsurface Energy and Environmental Protection)
►▼
Show Figures
Figure 1
Open AccessArticle
Analysis of the Combined Effect of Major Influencing Parameters for Designing High-Performance Single (sBHE) and Double (dBHE) U-Tube Borehole Heat Exchangers
by
Esa Dube Kerme, Alan S. Fung and Wey H. Leong
Energies 2024, 17(11), 2525; https://doi.org/10.3390/en17112525 - 23 May 2024
Abstract
In this paper, a comprehensive analysis of the combined effect of major influencing parameters on heat transfer in a single U-tube BHE (sBHE) and a double U-tube BHE (dBHE) with two independent circuits was performed by using a validated numerical heat transfer model.
[...] Read more.
In this paper, a comprehensive analysis of the combined effect of major influencing parameters on heat transfer in a single U-tube BHE (sBHE) and a double U-tube BHE (dBHE) with two independent circuits was performed by using a validated numerical heat transfer model. Geometrical parameters, such as shank spacing (with maximum, average, and minimum values), borehole diameter (large, medium, and small borehole sizes), and borehole depth (shallow, average, and deep borehole depths) as well as the thermal conductivity of soil and grout, which ranges from minimum to high values, were considered. The combined impact of these parameters was included under the following four major cases: (1) the combined effect of borehole depth, borehole size, and shank spacing; (2) the combined effect of borehole depth and soil and grout thermal conductivity; (3) the combined effect of soil and grout thermal conductivity and borehole size; and (4) the combined effect of soil thermal conductivity, borehole size, and shank spacing. Each of these major cases has nine different design options for both sBHEs and dBHEs. A series of results of heat transfer per unit borehole depth were generated for all the considered various cases. With the given parameters, the BHE case that provides the highest heat transfer among the various cases of sBHEs and dBHEs were obtained.
Full article
(This article belongs to the Special Issue New Insights into Geo-Energy, Geo-Resources and Environment)
►▼
Show Figures
Figure 1
Open AccessReview
Evaluation of Biohydrogen Production Depending on the Substrate Used—Examples for the Development of Green Energy
by
Zbigniew Jarosz, Magdalena Kapłan, Kamila Klimek, Dorota Anders, Barbara Dybek, Marcin Herkowiak, Jakub T. Hołaj-Krzak, Serhiy Syrotyuk, Serhiy Korobka, Hanna Syrotyuk and Grzegorz Wałowski
Energies 2024, 17(11), 2524; https://doi.org/10.3390/en17112524 - 23 May 2024
Abstract
Biohydrogen production is a promising alternative to replace fossil fuels in an environmentally friendly way. In addition to the many available renewable energy sources, the production of “colored” hydrogen and biohydrogen occupies an irreplaceable position due to the undeniable availability of biomass and
[...] Read more.
Biohydrogen production is a promising alternative to replace fossil fuels in an environmentally friendly way. In addition to the many available renewable energy sources, the production of “colored” hydrogen and biohydrogen occupies an irreplaceable position due to the undeniable availability of biomass and the need to manage food waste (FW). This article presents the current state of biohydrogen production technology—examples on continents (America, Africa, Asia, Australia and Oceania) and in Europe in terms of the efficiency of dark methane fermentation (CH4). Biophotolysis processes leading to the production of biohydrogen are indicated: directly and indirectly. The mechanism of the fermentation process of obtaining hydrogen and two-stage hydrogen fermentation are presented. The novelty of this article is the development of innovative trends in the development of the biohydrogen industry in Europe. Various models of the biohydrogen process are presented for different raw materials and proportions of substrates used in co-fermenters. Researchers from China are the undisputed pioneers in the use of renewable energy sources. However, improved energy self-sufficiency and environmental impacts are reflected in the growing number of pilot installations operating in European countries. This also gives hope for rapid progress towards full animal and FW management also in Poland.
Full article
(This article belongs to the Section B: Energy and Environment)
Open AccessArticle
Frequency Regulation Adaptive Control Strategy of Wind Energy Storage System for Wind Speed Uncertainty
by
Changqing Chen and Lixiong Li
Energies 2024, 17(11), 2523; https://doi.org/10.3390/en17112523 - 23 May 2024
Abstract
In order to reduce the negative influence of wind speed randomness and prediction error on frequency modulation, the reliability of the wind storage system was assessed effectively. In the wind storage frequency modulation system, a state of charge (SOC) adaptive adjustment method for
[...] Read more.
In order to reduce the negative influence of wind speed randomness and prediction error on frequency modulation, the reliability of the wind storage system was assessed effectively. In the wind storage frequency modulation system, a state of charge (SOC) adaptive adjustment method for wind speed randomness is proposed. Firstly, through the correlation analysis between the standby capacity of frequency modulation and the output power of wind turbine, the uncertainty of its frequency modulation capacity is revealed. Secondly, in view of the uncertainty of wind turbine frequency modulation, the output power of energy storage frequency modulation is optimized with the goal of minimizing the frequency modulation power deviation of the wind storage front under the framework of model predictive control, and the improved whale optimization algorithm (WOA) is used to solve the problem. Finally, the simulation results show that, under the given 5 min continuous disturbance, the root mean square of frequency regulation of the proposed restoration method is reduced by 56.65% compared to the SOC recovery base point set to 0.5. Under continuous large perturbations, the maximum frequency deviation is reduced by 0.0455 Hz. This effectively shows that this method can not only improve the frequency modulation reliability of wind power system but also improve the continuous frequency modulation capability of energy storage system.
Full article
(This article belongs to the Special Issue Development of Energy Harvesting Systems and Methods from Uncommon Sources)
Open AccessArticle
Experimental and DFT Studies of Influence of Flue Gas Components on the Interaction between CaO and As during Sludge Combustion
by
Yilin Shi, Huan Zhang, Jingxiang Yu, Youxiang Feng and Yan Jin
Energies 2024, 17(11), 2522; https://doi.org/10.3390/en17112522 - 23 May 2024
Abstract
The problem of As pollution emission from sludge during combustion has received widespread attention. The impact of flue gas components on the interaction with CaO and As during sludge combustion was analyzed using a series of experimental characterization methods. The strength of the
[...] Read more.
The problem of As pollution emission from sludge during combustion has received widespread attention. The impact of flue gas components on the interaction with CaO and As during sludge combustion was analyzed using a series of experimental characterization methods. The strength of the activity of As2O3 on the CaO(001) surface as well as on the CO2/SO2/H2O+CaO(001) surface with different O adsorption sites was revealed by combining with Density Functional Theory (DFT). According to the results, CO2 in the flue gas reacted with CaO in a reversible carbonation reaction, which optimized the pore structure of the solid phase products and promoted the capture of As by CaO. SO2 in the flue gas reacted with CaO in a sulfation reaction reaction to block the pores, which was not conducive to the capture of As by CaO. The presence of moisture led to poor pore structure collapse of the solid phase products as well as the formation of gehlenite, which reduced the enrichment of As by CaO. DFT calculations showed that the adsorption of As2O3 molecules on the CO2+CaO(001) surface was affected by the position of the O active site, and the adsorption energy at the OC1 top site was higher than that on the clean surface, which was favorable for the stable adsorption of As2O3 molecules. The existence of SO2 decreased As2O3 molecules’ adsorption energy on the CaO(001) surface, which was unfavorable for the adsorption of As2O3 molecules. There were two main effects of H2O molecules on the adsorption of As2O3 on the CaO(001) surface. One was the H2O molecules weakened the interaction between the As atoms and Osurf atoms, which was unfavorable to the adsorption of As2O3 molecules; the other was the existence of stronger adsorption of O atoms in H2O molecules on As atoms in As2O3 molecules, which made As2O3 molecules adsorbed at the top of OH0 adsorbed with adsorption energies much larger than that of clean surface, and the adsorption was more stable.
Full article
(This article belongs to the Special Issue Zero Carbon Emissions, Green Environment and Sustainable Energy)
►▼
Show Figures
Figure 1
Open AccessArticle
The Impact of Green Finance and Financial Technology on Regional Green Energy Technological Innovation Based on the Dual Machine Learning and Spatial Econometric Models
by
Mingyue Xie, Suning Zhao and Kun Lv
Energies 2024, 17(11), 2521; https://doi.org/10.3390/en17112521 - 23 May 2024
Abstract
Regional green energy technological innovation is an important means to alleviate economic–environmental contradictions. The purpose of this study was to explore the mechanisms of green finance, financial technology, and regional green energy technological innovation. In this study, we constructed dual machine learning models,
[...] Read more.
Regional green energy technological innovation is an important means to alleviate economic–environmental contradictions. The purpose of this study was to explore the mechanisms of green finance, financial technology, and regional green energy technological innovation. In this study, we constructed dual machine learning models, spatial econometric models, and panel threshold effect models to investigate the effects of green finance and financial technology on regional green energy technological innovation, using panel data from 266 cities nationwide from 2009 to 2021. The research findings are as follows: (1) Both green finance and financial technology significantly promote regional green energy technological innovation. (2) Based on a spatial weight matrix embedded in economic geography, both green finance and financial technology generate positive spatial spillover effects on regional green energy technological innovation. (3) The interaction between green finance and financial technology significantly contributes to regional green energy technological innovation. Financial technology can strengthen the positive local and neighboring effects of green finance on regional green energy technological innovation. (4) Based on the threshold effect of financial technology, green finance cannot significantly promote regional green energy technological innovation when financial technology is in an underdeveloped stage. With the advancement of financial technology, green finance continues to have a positive impact on regional green energy technological innovation. Based on this analysis and our conclusions, we propose practical policy recommendations that can provide a more sustainable approach to green energy technology innovation.
Full article
(This article belongs to the Special Issue Circular Business Models and Circular Economy in Energy Production and Consumption)
►▼
Show Figures
Figure 1
Open AccessArticle
A Route for Bioenergy in the Sahara Region: Date Palm Waste Valorization through Updraft Gasification
by
Mohammed Djaafri, Fethya Salem, Slimane Kalloum, Umberto Desideri, Pietro Bartocci, Mostefa Khelafi, Abdulaziz E. Atabani and Arianna Baldinelli
Energies 2024, 17(11), 2520; https://doi.org/10.3390/en17112520 - 23 May 2024
Abstract
The Adrar region (Algeria) has a total of 397,800 date palm trees (Phoenix dactylifera L.). Due to annual palm cleaning, large quantities of lignocellulosic biomass are produced. Depending on the variety, an average of 65 kg of biowaste is obtained per palm
[...] Read more.
The Adrar region (Algeria) has a total of 397,800 date palm trees (Phoenix dactylifera L.). Due to annual palm cleaning, large quantities of lignocellulosic biomass are produced. Depending on the variety, an average of 65 kg of biowaste is obtained per palm tree. Since the value of this biowaste is underrated, most of the palms are burned outdoors, causing air and visual pollution. This work explores the gasification potential of lignocellulosic waste from date palms (Phoenix dactylifera L. Takarbouche variety) into useful energy. The technology investigated is air updraft fixed-bed gasification, thanks to an originally designed and built reactor, with the capability to process 1 kg of feedstock. Four types of palm waste—namely, palms, petioles, bunch, and bunch peduncles—are first characterized (bulk density, proximate analysis, fixed carbon, elemental composition, and calorific value) and then used as feedstock for two gasification tests each. The syngas produced for the four date palm wastes is combustible, with an outlet temperature between 200 and 400 °C. The operating temperature inside the gasifier varies according to the feature of the biomass cuts (from 174 °C for the peduncles to 557 °C for palms). The experimental setup is also equipped with a cyclone, allowing for the recovery of some of the tar produced during the tests. Finally, the results show that the residence time has a positive effect on the conversion rate of date palm waste, which can significantly increase it to values of around 95%.
Full article
(This article belongs to the Special Issue Advances in Fuels and Combustion)
►▼
Show Figures
Figure 1
Open AccessArticle
Model Predictive Control of a Modular Multilevel Converter with Reduced Computational Burden
by
Hussein Kadhum, Alan J. Watson, Marco Rivera, Pericle Zanchetta and Patrick Wheeler
Energies 2024, 17(11), 2519; https://doi.org/10.3390/en17112519 - 23 May 2024
Abstract
Recent advances in high-power applications employing voltage source converters have been primarily fuelled by the emergence of the modular multilevel converter (MMC) and its derivatives. Model predictive control (MPC) has emerged as an effective way of controlling these converters because of its high
[...] Read more.
Recent advances in high-power applications employing voltage source converters have been primarily fuelled by the emergence of the modular multilevel converter (MMC) and its derivatives. Model predictive control (MPC) has emerged as an effective way of controlling these converters because of its high response. However, the practical implementation of MPC encounters hurdles, particularly in MMCs featuring many sub-modules per arm. This research introduces an approach termed folding model predictive control (FMPC), coupled with a pre-processing sorting algorithm, tailored for modular multilevel converters. The objective is to alleviate a significant part of the computational burden associated with the control of these converters. The FMPC framework combines multiple control objectives, encompassing AC current, DC current, circulating current, arm energy, and leg energy, within a unified cost function. Both simulation studies and real-time hardware-in-the-loop (HIL) testing are conducted to verify the efficacy of the proposed FMPC. The findings underscore the FMPC’s ability to deliver fast response and robust performance under both steady-state and dynamic operating conditions. Moreover, the FMPC adeptly mitigates circulating currents, reduces total harmonic distortion (THD%), and upholds capacitor voltage stability within acceptable thresholds, even in the presence of harmonic distortions in the AC grid. The practical applicability of MMCs, notwithstanding the presence of a large number of sub-modules (SMs) per arm, is facilitated by the significant reduction in switching states and computational overhead achieved through the FMPC approach.
Full article
(This article belongs to the Section F3: Power Electronics)
Open AccessArticle
Grid Model of Energy Consumption Using Random Forest by Integrating Data on the Nighttime Light, Population, and Urban Impervious Surface (2000–2020) in the Guangdong–Hong Kong–Macau Greater Bay Area
by
Yanfei Lei, Chao Xu, Yunpeng Wang and Xulong Liu
Energies 2024, 17(11), 2518; https://doi.org/10.3390/en17112518 - 23 May 2024
Abstract
Energy consumption is an important indicator for measuring economic development and is closely related to the atmospheric environment. As a demonstration zone for China’s high-quality development, the Guangdong–Hong Kong–Macao Greater Bay Area imposes higher requirements on ecological environment and sustainable development. Therefore, accurate
[...] Read more.
Energy consumption is an important indicator for measuring economic development and is closely related to the atmospheric environment. As a demonstration zone for China’s high-quality development, the Guangdong–Hong Kong–Macao Greater Bay Area imposes higher requirements on ecological environment and sustainable development. Therefore, accurate data on energy consumption is crucial for high-quality green development. However, the statistical data on local energy consumption in China is insufficient, and the lack of data is severe, which hinders the analysis of energy consumption at the metropolitan level and the precise implementation of energy policies. Nighttime light data have been widely used in the inversion of energy consumption, but they can only reflect socio-economic activities at night with certain limitations. In this study, a random forest model was developed to estimate metropolitan-level energy consumption in the Guangdong–Hong Kong–Macao Greater Bay Area from 2000 to 2020 based on nighttime light data, population data, and urban impervious surface data. The estimation results show that our model shows good performance with an R2 greater than 0.9783 and MAPE less than 9%. A long time series dataset from 2000 to 2020 on energy consumption distribution at a resolution of 500 m in the Guangdong–Hong Kong–Macao Greater Bay Area was built using our model with a top-down weight allocation method. The spatial and temporal dynamics of energy consumption in the Greater Bay Area were assessed at both the metropolitan and grid levels. The results show a significant increase in energy consumption in the Greater Bay Area with a clear clustering, and approximately 90% of energy consumption is concentrated in 22% of the area. This study established an energy consumption estimation model that comprehensively considers population, urban distribution, and nighttime light data, which effectively solves the problem of missing statistical data and accurately reflects the spatial distribution of energy consumption of the whole Bay Area. This study provides a reference for spatial pattern analysis and refined urban management and energy allocation for regions lacking statistical data on energy consumption.
Full article
(This article belongs to the Section K: State-of-the-Art Energy Related Technologies)
►▼
Show Figures
Figure 1
Open AccessArticle
Analysis of Power System Electromagnetic Transients Using the Finite Element Technique
by
Ivica Jurić-Grgić, Dino Lovrić and Ivan Krolo
Energies 2024, 17(11), 2517; https://doi.org/10.3390/en17112517 - 23 May 2024
Abstract
In this paper, a numerical model for the analysis of electromagnetic transients in a power system, based on the finite element technique, was developed. The simplicity of the finite element technique is manifested in the fact that the problem of solving any mathematically
[...] Read more.
In this paper, a numerical model for the analysis of electromagnetic transients in a power system, based on the finite element technique, was developed. The simplicity of the finite element technique is manifested in the fact that the problem of solving any mathematically described phenomena in an area is reduced to solving those same phenomena in a small part of that area, i.e., finite elements. Based on appropriate mathematical models, numerical models of the synchronous generator and other parts of the power system have been developed. System of differential equations of each power system element have been included in the numerical model in such a way that we employ numerical integration of the differential equations using the generalized trapezoidal rule ( -method) and reduce it to a system of algebraic equations in each time step. In a practical sense, this method enables a very simple solution to the problem of a real power system, i.e., a system with many generators, transformers, transmission lines and other elements. The accuracy of the developed numerical model for the analysis of electromagnetic transients in a power system has been confirmed by comparing the calculated results with the results obtained using the EMTP software (version 3.3) package.
Full article
(This article belongs to the Special Issue Energy, Electrical and Power Engineering 2024)
Open AccessArticle
Analyzing Potential Failures and Effects in a Pilot-Scale Biomass Preprocessing Facility for Improved Reliability
by
Rachel M. Emerson, Nepu Saha, Pralhad H. Burli, Jordan L. Klinger, Tiasha Bhattacharjee and Lorenzo Vega-Montoto
Energies 2024, 17(11), 2516; https://doi.org/10.3390/en17112516 - 23 May 2024
Abstract
This study demonstrates a failure identification methodology applied to a preprocessing facility generating conversion-ready feedstocks from biomass meeting conversion process critical quality attribute (CQA) specifications. Failure Modes and Effects Analysis (FMEA) was used as an industrially relevant risk analysis approach to evaluate a
[...] Read more.
This study demonstrates a failure identification methodology applied to a preprocessing facility generating conversion-ready feedstocks from biomass meeting conversion process critical quality attribute (CQA) specifications. Failure Modes and Effects Analysis (FMEA) was used as an industrially relevant risk analysis approach to evaluate a logging residue preprocessing system to prepare feedstock for pyrolysis conversion. Risk evaluations considered both system-level and operation unit-level assessments considering process efficiency, product quality, cost, sustainability, and safety. Key outputs included estimations of semi-quantitative risk scores for each failure, identification of the failure impacts, identification of failure causes associated with material attributes and process parameters, ranking success rates of failure detection methods, and speculation of potential mitigation strategies for decreasing failure risk scores. Results showed that deviations from moisture specifications had cascading consequences for other CQAs along with process safety implications. Failures linked to fixed carbon specifications carried the highest risk scores for product quality and process efficiency impacts. As increased throughput can be inversely related to meeting product quality specifications; achieving throughput and other material-based CQAs simultaneously will likely require system optimization or prioritization based on system economics. Ultimately, this work successfully demonstrates FMEA as a risk analysis approach for other bioenergy process systems.
Full article
(This article belongs to the Special Issue Thermochemical Conversions of Biomass and Its Safety Evaluation)
►▼
Show Figures
Figure 1
Open AccessArticle
A Long-Term Power Supply Risk Evaluation Method for China Regional Power System Based on Probabilistic Production Simulation
by
Jianzu Hu, Yuefeng Wang, Fan Cheng and Hanqing Shi
Energies 2024, 17(11), 2515; https://doi.org/10.3390/en17112515 - 23 May 2024
Abstract
To qualify the risk of extreme weather events for power supply security during the long-term power system transformation process, this paper proposes a risk probability evaluation method based on probabilistic production simulation. Firstly, the internal relationship of extreme weather intensity and duration is
[...] Read more.
To qualify the risk of extreme weather events for power supply security during the long-term power system transformation process, this paper proposes a risk probability evaluation method based on probabilistic production simulation. Firstly, the internal relationship of extreme weather intensity and duration is depicted using the copula function, and the influences of extreme weather on power security are described using the guaranteed power output ability coefficient, which can provide the extreme scenario basis for probabilistic production simulation. Then, a probabilistic production simulation method is proposed, which includes a typical-year scenario and extreme weather events. Meanwhile, an index system is proposed to qualify the power security level, which applies the loss of load expectation (LOLE) and time of loss of load expectation (TOLE) under different scenarios and other indices to reveal the long-term power security trend. Finally, the long-term power supply risks for the Yunnan provincial power system are analyzed using the proposed method, validating that the proposed method is capable of characterizing the influences of extreme weather on power security. The security level of different long-term power transformation schemes is evaluated.
Full article
(This article belongs to the Special Issue Sustainable Management of Energy Resources, Energy Strategies and Climate Change—2nd Edition)
Open AccessArticle
Dynamic Clustering of Wind Turbines Using SCADA Signal Analysis
by
Pere Marti-Puig and Carles Núñez-Vilaplana
Energies 2024, 17(11), 2514; https://doi.org/10.3390/en17112514 - 23 May 2024
Abstract
This work explores the ability to dynamically group the Wind Turbine (WT) of a Wind Farm (WF) based on the behavior of some of their Supervisory Control And Data Acquisition (SCADA) signals to detect the turbines that exhibit abnormal behavior. This study is
[...] Read more.
This work explores the ability to dynamically group the Wind Turbine (WT) of a Wind Farm (WF) based on the behavior of some of their Supervisory Control And Data Acquisition (SCADA) signals to detect the turbines that exhibit abnormal behavior. This study is centered on a small WF of five WTs and uses the observation that the same signals from different WTs in the same WF coherently evolve temporally in a time domain, describing very similar waveforms. In this contribution, averaged signals from the SCADA system are used and omit maximums, minimums and standard deviations, focusing mainly on velocities and other slowly varying signals. For the temporal analysis, sliding windows of different temporal durations are explored. The signals are encoded using the Discrete Cosine Transform, which reduces the problem’s dimensions. A hierarchical tree is built in each time window. Clusters are formed by pruning the tree using a threshold interpretable in terms of distance. It is unnecessary to work with an a priori known number of clusters. A protocol for enumerating the clusters based on the tree’s shape is then established, making it easier to follow the evolution of the clusters over time. The capability to automatically identify WTs whose signals differ from the group’s behavior can alert and program preventive maintenance operations on such WTs before a major breakdown occurs.
Full article
(This article belongs to the Section A3: Wind, Wave and Tidal Energy)
Open AccessReview
Modeling of Heat and Mass Transfer in Cement-Based Materials during Cement Hydration—A Review
by
Barbara Klemczak, Aneta Smolana and Agnieszka Jędrzejewska
Energies 2024, 17(11), 2513; https://doi.org/10.3390/en17112513 - 23 May 2024
Abstract
Cement-based materials encompass a broad spectrum of construction materials that utilize cement as the primary binding agent. Among these materials, concrete stands out as the most commonly employed. The cement, which is the principal constituent of these materials, undergoes a hydration reaction with
[...] Read more.
Cement-based materials encompass a broad spectrum of construction materials that utilize cement as the primary binding agent. Among these materials, concrete stands out as the most commonly employed. The cement, which is the principal constituent of these materials, undergoes a hydration reaction with water, playing a crucial role in the formation of the hardened composite. However, the exothermic nature of this reaction leads to significant temperature rise within the concrete elements, particularly during the early stages of hardening and in structures of substantial thickness. This temperature rise underscores the critical importance of predictive modeling in this domain. This paper presents a review of modeling approaches designed to predict temperature and accompanying moisture fields during concrete hardening, examining different levels of modeling accuracy and essential input parameters. While modern commercial finite element method (FEM) software programs are available for simulating thermal and moisture fields in concrete, they are accompanied by inherent limitations that engineers must know. The authors further evaluate effective commercial software tools tailored for predicting these effects, intending to provide construction engineers and stakeholders with guidance on managing temperature and moisture impacts in early-age concrete.
Full article
(This article belongs to the Special Issue Advances in Numerical Modeling of Multiphase Flow and Heat Transfer)
Open AccessArticle
Nonlinear Impact of Topological Configuration of Coupled Inverter-Based Resources on Interaction Harmonics Levels of Power Flow
by
Masoud Safarishaal, Rasul Hemmati, Reza Saeed Kandezy, John N. Jiang, Chenxi Lin and Di Wu
Energies 2024, 17(11), 2512; https://doi.org/10.3390/en17112512 - 23 May 2024
Abstract
The increasing level of harmonics in the power grid, driven by a substantial presence of coupled inverter-based energy resources (IBRs), poses a new challenge to power grid transient stability. This paper presents the findings from experiments and analytical studies on the impact of
[...] Read more.
The increasing level of harmonics in the power grid, driven by a substantial presence of coupled inverter-based energy resources (IBRs), poses a new challenge to power grid transient stability. This paper presents the findings from experiments and analytical studies on the impact of the topological configuration of coupled IBRs on the level of power flow harmonics in a distribution grid: (i) our findings report that the impact of grid topology on harmonics is nonlinear, which is in contrast to the common perception that the power grid operates as a large linear low-pass filter for harmonics; (ii) importantly, this study highlights that the influence of the topological configuration of inverters on the reduction of system-level harmonics is more substantial than the effect of line impedance, emphasizing the significance of grid topological configuration; (iii) furthermore, the observed reduction in harmonics is attributed to a harmonic cancellation effect achieved through self-compensation by all the coupled inverters without affecting the active power flow in the power grid. These findings propose a new approach to limit the penetration of complex IBR harmonics in the power grid from a system-wide perspective. This approach significantly differs from the component-level or localized solutions used today, such as inverter control, power filtering, and transformer tap changes.
Full article
(This article belongs to the Section F1: Electrical Power System)
Open AccessArticle
Jerusalem Artichoke: Energy Balance in Annual and Perennial Cropping Systems—A Case Study in North-Eastern Poland
by
Krzysztof Józef Jankowski and Bożena Bogucka
Energies 2024, 17(11), 2511; https://doi.org/10.3390/en17112511 - 23 May 2024
Abstract
This article presents the results of a three-year experiment (2018–2020) conducted at the Agricultural Experiment Station in Bałcyny (north-eastern Poland) with the aim of determining Jerusalem artichoke (JA) yields and the energy balance of biomass production in (i) a perennial cropping system (only
[...] Read more.
This article presents the results of a three-year experiment (2018–2020) conducted at the Agricultural Experiment Station in Bałcyny (north-eastern Poland) with the aim of determining Jerusalem artichoke (JA) yields and the energy balance of biomass production in (i) a perennial cropping system (only aerial biomass was harvested each year) and (ii) an annual cropping system (both aerial biomass and tubers were harvested each year). When JA was grown as a perennial crop, the demand for energy reached 25.2 GJ ha−1 in the year of plantation establishment and 12.3–13.4 GJ ha−1 in the second and third year of production. The energy inputs associated with the annual cropping system were determined in the range of 31.4–37.1 GJ ha−1. Biomass yields were twice as high in the annual than in the perennial cropping system (20.98 vs. 10.30 Mg DM ha−1). Tuber yield accounted for 46% of the total yield. The energy output of JA biomass was 1.8 times higher in the annual than in the perennial cropping system (275.4 vs. 157.3 GJ ha−1). The average energy gain in JA cultivation ranged from 140 (perennial crop) to 241 GJ ha−1 (annual crop). The energy efficiency ratio of JA biomass production reached 7.7–13.3 in the perennial cropping system, and it was 20% lower in the annual cropping system. These results imply that when JA was grown as an annual crop, an increase in energy inputs associated with plantation establishment (tillage and planting) and the harvest and transport of tubers was not fully compensated by the energy output of tubers.
Full article
(This article belongs to the Special Issue Green Energy from Soil Remediation)
►▼
Show Figures
Figure 1
Open AccessArticle
Dynamic Response Study of Overhead Contact System Portal Structure Based on Vehicle–Track–Bridge Coupled Vibration
by
Tao Li and Xia Zhao
Energies 2024, 17(11), 2510; https://doi.org/10.3390/en17112510 - 23 May 2024
Abstract
In light of the rapid development of electrified railways, the safety and stability of train operations, as well as the catenary’s interaction with current quality, have garnered widespread attention. Electrified train operation with additional track irregularities serves as a principal excitation source within
[...] Read more.
In light of the rapid development of electrified railways, the safety and stability of train operations, as well as the catenary’s interaction with current quality, have garnered widespread attention. Electrified train operation with additional track irregularities serves as a principal excitation source within the vehicle–bridge–catenary system, significantly influencing the vibration characteristics of the system. Addressing the aforementioned issues, we first established the vehicle–track dynamics model and the bridge–catenary finite element model based on the principles of coupled dynamics of the vehicle–track system. These models are interconnected using dynamic forces between the wheel and rail. Subsequently, within the vehicle–track coupled system, track random irregularities are introduced as input excitations for the coupled model, and the dynamic response of the system is simulated and solved. Then, the obtained wheel–rail forces are applied to the bridge–catenary coupled system finite element model in the form of time-varying moving load forces. Finally, the dynamic response characteristics of the catenary portal structure under different conditions are determined. Meanwhile, a study on the vibration characteristics of the truss-type pillar portal structure was conducted, and the results were compared with those of existing models. The results indicate that the vertical and lateral forces between the vehicle and track are positively correlated with the speed and irregularity amplitude. Response values such as the derailment coefficient and wheel load reduction rate are within the specified range of relevant standards. The low-order natural resonant frequency of the truss-type pillar structure has, on average, increased by 0.86 compared to the existing pillar structure, which signifies improved stability. Furthermore, under various conditions, the average reductions in maximum displacement and stress response of this pillar structure are 13.2% and 14.19%, respectively, in comparison to the existing pillar structure, rendering it more suitable for practical engineering applications.
Full article
(This article belongs to the Topic Structural Health Monitoring and Non-destructive Testing for Large-Scale Structures (2nd Edition))
Open AccessReview
The Economic Competitiveness of Hydrogen Fuel Cell-Powered Trucks: A Review of Total Cost of Ownership Estimates
by
Romeo Danielis, Mariangela Scorrano, Manuela Masutti, Asees Muhammad Awan and Arsalan Muhammad Khan Niazi
Energies 2024, 17(11), 2509; https://doi.org/10.3390/en17112509 - 23 May 2024
Abstract
This paper investigates the economic competitiveness of hydrogen-powered trucks. It reviews the growing number of papers that provide an estimate of the total cost of ownership (TCO) of hydrogen-powered trucks relative to their diesel equivalents. It examines the methodology applied, the variables considered,
[...] Read more.
This paper investigates the economic competitiveness of hydrogen-powered trucks. It reviews the growing number of papers that provide an estimate of the total cost of ownership (TCO) of hydrogen-powered trucks relative to their diesel equivalents. It examines the methodology applied, the variables considered, the data used for estimation, and the results obtained. All reviewed studies conclude that hydrogen-powered trucks are not currently cost-competitive, while they might become competitive after 2030. The conclusion holds across truck types and sizes, hydrogen pathways, mission profiles, and countries. However, we find that there is still a huge area of uncertainty regarding the purchase price of hydrogen-powered trucks and the cost of hydrogen, which hampers the reliability of the results obtained. Various areas of methodological improvements are suggested.
Full article
(This article belongs to the Special Issue The Interplay between Technologies and Energy Policies for Reducing the Environmental Impact of Transportation: Scenarios and Case Studies)
Journal Menu
► ▼ Journal Menu-
- Energies Home
- Aims & Scope
- Editorial Board
- Reviewer Board
- Topical Advisory Panel
- Instructions for Authors
- Special Issues
- Topics
- Sections & Collections
- Article Processing Charge
- Indexing & Archiving
- Editor’s Choice Articles
- Most Cited & Viewed
- Journal Statistics
- Journal History
- Journal Awards
- Society Collaborations
- Conferences
- Editorial Office
Journal Browser
► ▼ Journal BrowserHighly Accessed Articles
Latest Books
E-Mail Alert
News
Topics
Topic in
Energies, Materials, Processes, Solar, Sustainability
Solar Thermal Energy and Photovoltaic Systems, 2nd Volume
Topic Editors: Pedro Dinis Gaspar, Pedro Dinho da Silva, Luís C. PiresDeadline: 31 May 2024
Topic in
Applied Sciences, Electricity, Electronics, Energies, Sensors
Power System Protection
Topic Editors: Seyed Morteza Alizadeh, Akhtar KalamDeadline: 20 June 2024
Topic in
Economies, Energies, Mathematics, Sustainability
Energy Economics and Sustainable Development
Topic Editors: Cuihong Yang, Xiuting Li, Zhuoying Zhang, Xuerong LiDeadline: 30 June 2024
Topic in
Remote Sensing, Energies, Minerals, Geosciences, Geotechnics
Support Theory and Technology of Geotechnical Engineering
Topic Editors: Qi Wang, Bei Jiang, Xuezhen Wu, Hongke GaoDeadline: 20 July 2024
Conferences
Special Issues
Special Issue in
Energies
Transformation of Energy Systems: From the Perspective of Climate and Energy Policies
Guest Editors: Carmelina Cosmi, Senatro Di LeoDeadline: 24 May 2024
Special Issue in
Energies
Modeling and Simulation of Floating Offshore Wind Farms
Guest Editor: M. Salman SiddiquiDeadline: 31 May 2024
Special Issue in
Energies
Governance, Legislation and Economic Policy for Green Energy Production: The EU Green Deal Framework and Horizon 2030
Guest Editors: Antonio Sánchez-Bayón, Estrella Trincado, Jesús Alberto Valero-Matas, Rafael Rávina-RipollDeadline: 19 June 2024
Special Issue in
Energies
Tidal Turbines II
Guest Editors: Sylvain Guillou, Eric L. Bibeau, Jérôme ThiebotDeadline: 30 June 2024
Topical Collections
Topical Collection in
Energies
Featured Papers in Electrical Power and Energy System
Collection Editors: Nicu Bizon, Mihai Oproescu, Philippe Poure, Rocío Pérez de Prado, Abdessattar Abdelkefi
Topical Collection in
Energies
Energy Economics and Policy in Developed Countries
Collection Editor: Almas Heshmati
Topical Collection in
Energies
Editorial Board Members’ Collection Series: Advances in Power Converters
Collection Editors: Rosa Anna Mastromauro, Luigi Piegari
Topical Collection in
Energies
Artificial Intelligence and Smart Energy
Collection Editors: Wei-Hsin Chen, Núria Agell, Zhiyong Liu, Ying-Yi Hong