Energies

Research

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19 pages, 6650 KiB

Open AccessArticle

Research on the Blades and Performance of Semi-Submersible Wind Turbines with Different Capacities

by Jiaping Cui, Zhigang Cao, Pin Lyu, Huaiwu Peng, Quankun Li, Ruixian Ma and Yingming Liu

Energies 2024, 17(13), 3259; https://doi.org/10.3390/en17133259 - 2 Jul 2024

Viewed by 896

Abstract

With the gradual increase in the maturity of wind energy technology, floating offshore wind turbines have progressively moved from small-capacity demonstrations to large-capacity commercial applications. As a direct component of wind turbines used to capture wind energy, an increase in the blade length [...] Read more.

With the gradual increase in the maturity of wind energy technology, floating offshore wind turbines have progressively moved from small-capacity demonstrations to large-capacity commercial applications. As a direct component of wind turbines used to capture wind energy, an increase in the blade length directly leads to an increase in blade flexibility and a decrease in aerodynamic performance. Furthermore, if the floater has an additional six degrees of freedom, the movement and load of the blade under the combined action of wind and waves are more complicated. In this work, two types of semi-submersible wind turbines with different capacities are used as the research objects, and the load and motion characteristics of the blades of these floating offshore wind turbines are studied. Through the analysis of the simulation data, the following conclusions are drawn: with the increase in the capacity of the wind turbine, the flexible deformation of the blade increases, the movement range of the blade tip becomes larger, the blade root load increases, and the power fluctuation is more obvious. Compared with the bottom-fixed wind turbine, the flexible blade deformation of the floating offshore wind turbine is smaller; however, the blade root load is more dispersed, and the power output is more unstable and lower. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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16 pages, 1041 KiB

Open AccessArticle

Optimizing the Charging Mobility of WPT-Enabled UAV to Enhance the Stability of Solar-Powered LoRaWAN IoT

by Yujin Gong, Ikjune Yoon and Dong Kun Noh

Energies 2024, 17(7), 1617; https://doi.org/10.3390/en17071617 - 28 Mar 2024

Cited by 1 | Viewed by 923

Abstract

In the majority of Internet of Things (IoT) applications, persistent and stable operation is a crucial requirement. While environmental energy-harvesting technologies can enhance IoT’s persistence, they do not guarantee stability. Therefore, we aim to address the stability challenges in solar-powered IoT (SP-IoT) by [...] Read more.

In the majority of Internet of Things (IoT) applications, persistent and stable operation is a crucial requirement. While environmental energy-harvesting technologies can enhance IoT’s persistence, they do not guarantee stability. Therefore, we aim to address the stability challenges in solar-powered IoT (SP-IoT) by employing wireless power transmission (WPT) through unmanned aerial vehicles (UAVs). This study focuses on determining the optimal charging mobility of drones for WPT to enhance the stability of nodes operating in a wide area network (WAN)-based SP-IoT environment. The proposed scheme identifies nodes with insufficient solar energy harvesting and defines the optimal charging mobility parameters (hovering position, hovering time, and moving path) to efficiently transmit the drone’s energy to these nodes in a balanced manner. The experimental results confirm that the proposed scheme significantly improves the stability of solar-powered IoT nodes by optimally utilizing the limited energy of the drone. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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25 pages, 9826 KiB

Open AccessArticle

Evaluation of a Database of the Spanish Wind Energy Resources Derived from a Regional Reanalysis

by Antonio Jiménez-Garrote, Francisco J. Santos-Alamillos, Guadalupe Sánchez-Hernández, Miguel López-Cuesta, José A. Ruiz-Arias and David Pozo-Vázquez

Energies 2024, 17(7), 1523; https://doi.org/10.3390/en17071523 - 22 Mar 2024

Viewed by 873

Abstract

An enhanced database (RetroDB) of the Spanish wind energy resources, derived from a high spatial resolution integration with the WRF model, is proposed and evaluated. RetroDB provides hourly capacity factor (CF) values for the Spanish regions, along the period of 2007–2020, with an [...] Read more.

An enhanced database (RetroDB) of the Spanish wind energy resources, derived from a high spatial resolution integration with the WRF model, is proposed and evaluated. RetroDB provides hourly capacity factor (CF) values for the Spanish regions, along the period of 2007–2020, with an unprecedented spatial resolution. RetroDB estimates were benchmarked based on the ERA5 global reanalysis. A comprehensive evaluation study of both RetroDB and ERA5 estimates was conducted using surface and tall mast measurements, along with actual CF values. The extent to which RetroDB and ERA5 reproduced the CF spatial variability, distribution, and ramp distribution were specifically addressed. The results showed no differences between the global and regional reanalysis performance regarding nationally aggregated wind energy estimates. Nevertheless, RetroDB clearly shows a superior performance reproducing the wind speeds’ and CFs’ spatial and temporal distributions. This was found to be related to the higher reliability of RetroDB reproducing the aloft winds in complex topographic areas. Overall, the results clearly indicate that, in areas such as the study region, where the wind resources are mostly associated with topographic enhancements, high spatial resolution regional reanalyses are preferable over relative coarse reanalyses (e.g., ERA5), particularly for wind energy integration studies. RetroDB database is made publicly available. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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28 pages, 6366 KiB

Open AccessArticle

Techno-Economic Performance and Sensitivity Analysis of an Off-Grid Renewable Energy-Based Hybrid System: A Case Study of Kuakata, Bangladesh

by Sheikh Md. Nahid Hasan, Shameem Ahmad, Abrar Fahim Liaf, A. G. M. B. Mustayen, M. M. Hasan, Tofael Ahmed, Sujan Howlader, Mahamudul Hassan and Mohammad Rafiqul Alam

Energies 2024, 17(6), 1476; https://doi.org/10.3390/en17061476 - 19 Mar 2024

Cited by 5 | Viewed by 1726

Abstract

Hybrid renewable energy sources (HRES) are increasingly being utilized to meet global energy demands, particularly in rural areas that rely on diesel generators and are disconnected from the utility grid, due to their environmental and human health benefits. This study investigates the performance [...] Read more.

Hybrid renewable energy sources (HRES) are increasingly being utilized to meet global energy demands, particularly in rural areas that rely on diesel generators and are disconnected from the utility grid, due to their environmental and human health benefits. This study investigates the performance of an off-grid, hybrid PV/diesel generator/battery system for a decentralized power plant in Kuakata, Bangladesh, meeting a load demand of 3000 kWh/day with a 501.61 kW peak load demand. HOMER Pro (hybrid optimization model for electric renewable) software (version 3.11) was used to simulate and optimize system operations utilizing real-time solar radiation and load profile data from that location. This study also includes a sensitivity analysis of the off-grid HRES system under different electrical load demands, project longevity, and derating variables. The results reveal that CO₂ emissions have potentially decreased by more than 30% and over 10 tons per year, respectively, when compared to traditional power plants. The optimized system’s net present cost (NPC) was determined to be around USD 5.19 million, with a cost of energy (COE) of USD 0.367 per kWh per unit with a 100% renewable component. Furthermore, the current study’s findings are compared to previous research that has resulted in an economical hybrid renewable energy system with an affordable COE. The hybrid energy system under consideration might also be applicable to other parts of the world with comparable climate conditions. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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18 pages, 4682 KiB

Open AccessArticle

A Numerical Method for the Dynamics Analysis of Blade Fracture Faults in Wind Turbines Using Geometrically Exact Beam Theory and Its Validation

by Xianyou Wu, Kai Feng and Qing’an Li

Energies 2024, 17(4), 824; https://doi.org/10.3390/en17040824 - 9 Feb 2024

Cited by 1 | Viewed by 1019

Abstract

In pursuit of China’s goals for carbon peak and carbon neutrality, wind turbines are continually evolving to achieve a lower levelized cost of energy. The primary technological focus in the wind power industry is on large-scale, lightweight designs for entire turbines to enhance [...] Read more.

In pursuit of China’s goals for carbon peak and carbon neutrality, wind turbines are continually evolving to achieve a lower levelized cost of energy. The primary technological focus in the wind power industry is on large-scale, lightweight designs for entire turbines to enhance cost competitiveness. However, this advancement has led to an increased risk of blade fractures under extreme operating conditions. This paper addresses this challenging issue by using geometrically exact beam theory to develop a nonlinear simulation model for long, flexible blades. The model accounts for sudden changes in blade properties at the moment of failure, covering both the extensive motions and deformations of the fractured blade. The validation of the proposed model is carried out by comparing the results from power production cases with bladed simulations and further validating the simulations of blade fracture load cases against measurement data. The methodologies and findings presented in this study offer valuable insights for diagnosing faults in wind turbines. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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25 pages, 12934 KiB

Open AccessArticle

Estimation of Solar Irradiance Using a Neural Network Based on the Combination of Sky Camera Images and Meteorological Data

by Lilla Barancsuk, Veronika Groma, Dalma Günter, János Osán and Bálint Hartmann

Energies 2024, 17(2), 438; https://doi.org/10.3390/en17020438 - 16 Jan 2024

Viewed by 1245

Abstract

In recent years, with the growing proliferation of photovoltaics (PV), accurate nowcasting of PV power has emerged as a challenge. Global horizontal irradiance (GHI), which is a key factor influencing PV power, is known to be highly variable as it is determined by [...] Read more.

In recent years, with the growing proliferation of photovoltaics (PV), accurate nowcasting of PV power has emerged as a challenge. Global horizontal irradiance (GHI), which is a key factor influencing PV power, is known to be highly variable as it is determined by short-term meteorological phenomena, particularly cloud movement. Deep learning and computer vision techniques applied to all-sky imagery are demonstrated to be highly accurate nowcasting methods, as they encode crucial information about the sky’s state. While these methods utilize deep neural network models, such as Convolutional Neural Networks (CNN), and attain high levels of accuracy, the training of image-based deep learning models demands significant computational resources. In this work, we present a computationally economical estimation technique, based on a deep learning model. We utilize both all-sky imagery and meteorological data, however, information on the sky’s state is encoded as a feature vector extracted using traditional image processing methods. We introduce six all-sky image features utilizing detailed knowledge of meteorological and physical phenomena, significantly decreasing the amount of input data and model complexity. We investigate the accuracy of the determined global and diffuse radiation for different combinations of meteorological parameters. The model is evaluated using two years of measurements from an on-site all-sky camera and an adjacent meteorological station. Our findings demonstrate that the model provides comparable accuracy to CNN-based methods, yet at a significantly lower computational cost. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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15 pages, 5766 KiB

Open AccessArticle

State of Charge Estimation of Lithium-Ion Battery Based on Back Propagation Neural Network and AdaBoost Algorithm

by Bingzi Cai, Mutian Li, Huawei Yang, Chunsheng Wang and Yougen Chen

Energies 2023, 16(23), 7824; https://doi.org/10.3390/en16237824 - 28 Nov 2023

Cited by 3 | Viewed by 1210

Abstract

The accurate estimation of the state of charge (SOC) of lithium-ion batteries is critical in battery energy storage systems. This paper introduces a novel approach, the AdaBoost–BPNN model, to overcome the limitations of traditional data-driven estimation methods, such as a low estimation accuracy [...] Read more.

The accurate estimation of the state of charge (SOC) of lithium-ion batteries is critical in battery energy storage systems. This paper introduces a novel approach, the AdaBoost–BPNN model, to overcome the limitations of traditional data-driven estimation methods, such as a low estimation accuracy and poor generalization ability. The proposed model employs a back propagation neural network (BPNN) for the preliminary estimation. Subsequently, an AdaBoost–BPNN model is developed as a strong learner using the AdaBoost integration algorithm. Each BPNN sub-model serves as a weak learner within the AdaBoost framework. The final output of the strong learner is obtained by combining the individual outputs from the weak learners using weighting factors. This adaptive adjustment of weighting factors enhances the accuracy of SOC estimation. The proposed SOC estimation algorithm is evaluated and validated through experimental analysis. Throughout the paper, theoretical analysis is conducted, and the proposed AdaBoost–BPNN model is validated and verified using experimental results. The results demonstrate that the AdaBoost–BPNN model outperforms traditional methods in accurately estimating SOC under various conditions, including constant current-constant voltage (CCCV) charging, dynamical stress testing (DST), US06, a federal urban driving schedule (FUDS), and pulse discharge conditions. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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16 pages, 6734 KiB

Open AccessArticle

Reactive Power Dispatch Algorithm for a Reduction in Power Losses in Offshore Wind Farms

by Seung-Ho Song, Gyo-Won Tae, Alexandr Lim and Ye-Chan Kim

Energies 2023, 16(21), 7426; https://doi.org/10.3390/en16217426 - 3 Nov 2023

Cited by 1 | Viewed by 926

Abstract

This paper presents a groundbreaking power distribution technique that focuses on the loss rate of individual wind turbines. Distinct from conventional methods, our strategy prioritizes seamless integration and adaptability within wind farm management systems. By evaluating power losses in specific branches of a [...] Read more.

This paper presents a groundbreaking power distribution technique that focuses on the loss rate of individual wind turbines. Distinct from conventional methods, our strategy prioritizes seamless integration and adaptability within wind farm management systems. By evaluating power losses in specific branches of a wind farm, our approach enhances overall performance by strategically allocating reactive power to reduce cumulative losses. When compared to traditional uniform distribution and Particle Swarm Optimization (PSO) methods, our innovative approach stands out for its superior efficiency and adaptability. Comprehensive simulations underline the strengths and weaknesses of prevailing methods and underscore the superior efficacy of our proposed technique. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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16 pages, 2582 KiB

Open AccessArticle

Analysis of the Impact of Integrating Variable Renewable Energy into the Power System in the Colombian Caribbean Region

by Carlos Arturo Cárdenas Guerra, Adalberto José Ospino Castro and Rafael Peña Gallardo

Energies 2023, 16(21), 7260; https://doi.org/10.3390/en16217260 - 26 Oct 2023

Cited by 2 | Viewed by 1447

Abstract

This paper compares the effects of adding solar and wind power to the power system of Colombia’s Caribbean region and its connections to the National Interconnected System. A base scenario was simulated in the PowerFactory 2003 software considering the actual data of the [...] Read more.

This paper compares the effects of adding solar and wind power to the power system of Colombia’s Caribbean region and its connections to the National Interconnected System. A base scenario was simulated in the PowerFactory 2003 software considering the actual data of the power system in 2023, and then, they were compared with the results obtained for 2033, considering the growth of the network and the addition of new power plants based on variable renewable energy. The comparison analyzes the impact of the newly added renewable energy in the power system on the voltage stability and system frequency. The results obtained show that the addition of new variable renewable energy plants generates voltage fluctuations in the lower voltage levels, ranging from 1% to 3.1%, which indicates potential challenges in maintaining the voltage stability. In higher voltages, no significant variations were found. Regarding the system frequency, the transient value tends to increase but is within the regulatory range, with variations of less than 0.2 Hz. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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15 pages, 2776 KiB

Open AccessArticle

Simulated Impact of Shortened Strings in Commercial and Utility-Scale Photovoltaic Arrays

by Ryan M. Smith, Manjunath Matam and Hubert Seigneur

Energies 2023, 16(21), 7222; https://doi.org/10.3390/en16217222 - 24 Oct 2023

Cited by 1 | Viewed by 1016

Abstract

The deliberate removal of photovoltaic modules from a string can occur for various reasons encompassing maintenance, measurements, theft, or failure, reducing that string length relative to others when replacement modules are not available and there are not any viable alternative makes and models [...] Read more.

The deliberate removal of photovoltaic modules from a string can occur for various reasons encompassing maintenance, measurements, theft, or failure, reducing that string length relative to others when replacement modules are not available and there are not any viable alternative makes and models that could be inserted. This phenomenon, delineated in our prior experimentally validated research, manifests two significant effects: (1) a shift in the ideal maximum power point and (2) the induction of potentially substantial reverse currents in the shortened strings at open-circuit voltage, V_OC. However, the scalability and asymptotic limits of these observed behaviors concerning array size remained undetermined. In this study, we elucidate the operational dynamics of such arrays by manipulating two mismatch-contributing variables in simulated arrays of up to 900 strings: the number of removed modules per string (indicative of the level of mismatch, ranging up to 5) and the quantity of shortened strings (1 to 60). Simulation outcomes underscore that mismatch severity impacts array operation more than the proportion of shortened strings. This research delves into the practical ramifications of operating with shortened strings, including implications for low-irradiance operation and the manifestation of deleterious reverse currents (>35 A in specific cases), emphasizing the need for careful array configuration for optimal performance and safety in these implementations. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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17 pages, 2468 KiB

Open AccessArticle

Refined Equivalent Modeling Method for Mixed Wind Farms Based on Small Sample Data

by Qianlong Zhu, Wenjing Xiong, Haijiao Wang and Xiaoqiang Jin

Energies 2023, 16(20), 7191; https://doi.org/10.3390/en16207191 - 21 Oct 2023

Cited by 2 | Viewed by 1781

Abstract

For equivalent modeling of mixed wind farms (WFs), existing clustering indicators cannot consider the complex coupling characteristics between different types of wind turbines (WTs). In this paper, a refined equivalent modeling approach based on artificial intelligence technology is proposed. Firstly, the electromechanical transient [...] Read more.

For equivalent modeling of mixed wind farms (WFs), existing clustering indicators cannot consider the complex coupling characteristics between different types of wind turbines (WTs). In this paper, a refined equivalent modeling approach based on artificial intelligence technology is proposed. Firstly, the electromechanical transient performance of mixed WFs is analyzed. The WT type, wind speed and direction, and voltage dip are considered the dominant factors affecting the external dynamic response of mixed WFs. Secondly, the equivalent node model is established, including the selection of independent and dependent variables. Then, the multiple artificial neural networks (ANNs) are trained one by one based on small sample data, to fit the nonlinear relationship between the dependent variables and the independent variables. Finally, the dynamic response of the power systems with a mixed WF is simulated in the MATLAB platform. A comparison of the errors in electromechanical phenomena demonstrates that the proposed model can reflect the external characteristics of the test mixed WF in different wind conditions and voltage dips. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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20 pages, 4211 KiB

Open AccessArticle

Modeling and Simulating Wind Energy Generation Systems by Means of Co-Simulation Techniques

by Loan Tullio F. W. da Silva, Marcelo Aroca Tomim, Pedro Gomes Barbosa, Pedro Machado de Almeida and Robson Francisco da Silva Dias

Energies 2023, 16(19), 7013; https://doi.org/10.3390/en16197013 - 9 Oct 2023

Cited by 1 | Viewed by 1752

Abstract

This paper presents the development of a wind energy conversion system co-simulation based on the Functional Mock-up Interface standard aiming at contributing to the development of co-simulation of large electrical power systems by means of open-source and standardized computational tools. Co-simulation enables the [...] Read more.

This paper presents the development of a wind energy conversion system co-simulation based on the Functional Mock-up Interface standard aiming at contributing to the development of co-simulation of large electrical power systems by means of open-source and standardized computational tools. Co-simulation enables the computational burden of a monolithic simulation to be shared among several processing units, significantly reducing processing time. Through the Functional Mock-up Interface standard, developed models are encapsulated into Functional Mock-up Unit, providing an extra means for the protection of intellectual property, a very appealing feature for end users, both in industry and academia. To achieve the decoupling of the subsystems, the Bergeron ideal transmission line model will be used, with travel time equal to the simulation time-step. The computational performance and effectiveness of the proposed co-simulation technique was evaluated with a wind power plant with 50 wind turbines. The system digital models were developed into Modelica language, while co-simulation was implemented in Python. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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Review

Jump to: Research

28 pages, 3562 KiB

Open AccessReview

Circular Economy Aspects of Permanent Magnet Synchronous Reluctance Machine Design for Electric Vehicle Applications: A Review

by Mihály Katona and Tamás Orosz

Energies 2024, 17(6), 1408; https://doi.org/10.3390/en17061408 - 14 Mar 2024

Cited by 3 | Viewed by 2046

Abstract

Innovative technological solutions have become increasingly critical in addressing the transportation sector’s environmental impact. Passenger vehicles present an opportunity to introduce novel drivetrain solutions that can quickly penetrate the electric vehicle market due to their shorter development time and lifetime compared to commercial [...] Read more.

Innovative technological solutions have become increasingly critical in addressing the transportation sector’s environmental impact. Passenger vehicles present an opportunity to introduce novel drivetrain solutions that can quickly penetrate the electric vehicle market due to their shorter development time and lifetime compared to commercial vehicles. As environmental policy pressure increases and customers demand more sustainable products, shifting from a linear business approach to a circular economy model is in prospect. The new generation of economically competitive machines must be designed with a restorative intention, considering future reuse, refurbishment, remanufacture, and recycling possibilities. This review investigates the market penetration possibilities of permanent magnet-assisted synchronous reluctance machines for mini and small-segment electric vehicles, considering the urban environment and sustainability aspects of the circular economy model. When making changes to the materials used in an electric machine, it is crucial to evaluate their potential impact on efficiency while keeping the environmental impact of those materials in mind. The indirect ecological effect of the vehicle’s use phase may outweigh the reduction in manufacturing and recycling at its end-of-life. Therefore, thoroughly analysing the materials used in the design process is necessary to ensure maximum efficiency while minimising the environmental impact. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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22 pages, 2700 KiB

Open AccessReview

Current Challenges in Operation, Performance, and Maintenance of Photovoltaic Panels

by Tamás Orosz, Anton Rassõlkin, Pedro Arsénio, Peter Poór, Daniil Valme and Ádám Sleisz

Energies 2024, 17(6), 1306; https://doi.org/10.3390/en17061306 - 8 Mar 2024

Cited by 4 | Viewed by 2051

Abstract

The installed solar capacity in the European Union has expanded rapidly in recent years. The production of these plants is stochastic and highly dependent on the weather. However, many factors should be considered together to estimate the expected output according to the weather [...] Read more.

The installed solar capacity in the European Union has expanded rapidly in recent years. The production of these plants is stochastic and highly dependent on the weather. However, many factors should be considered together to estimate the expected output according to the weather forecast so that these new PV plants can operate at maximum capacity. Plants must be operated in coordination with maintenance operations and considering actual energy market prices. Various methods have recently been developed in the literature, ranging from the most impactful artificial-intelligence-based generation estimation methods to various diagnostic and maintenance methods. Moreover, the optimal operational and maintenance strategy usually depends on market regulation, and there are many concerns related to the distribution system operator. This review article aims to summarize and illustrate the challenges of operating and maintaining solar power plants and the economic and technical importance of these problems. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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33 pages, 999 KiB

Open AccessFeature PaperReview

Voltage Optimization in Active Distribution Networks—Utilizing Analytical and Computational Approaches in High Renewable Energy Penetration Environments

by Mohammed Alshehri and Jin Yang

Energies 2024, 17(5), 1216; https://doi.org/10.3390/en17051216 - 3 Mar 2024

Cited by 3 | Viewed by 2133

Abstract

This review paper synthesizes the recent advancements in voltage regulation techniques for active distribution networks (ADNs), particularly in contexts with high renewable energy source (RES) penetration, using photovoltaics (PVs) as a highlighted example. It covers a comprehensive analysis of various innovative strategies and [...] Read more.

This review paper synthesizes the recent advancements in voltage regulation techniques for active distribution networks (ADNs), particularly in contexts with high renewable energy source (RES) penetration, using photovoltaics (PVs) as a highlighted example. It covers a comprehensive analysis of various innovative strategies and optimization algorithms aimed at mitigating voltage fluctuations, optimizing network performance, and integrating smart technologies like smart inverters and energy storage systems (ESSs). The review highlights key developments in decentralized control algorithms, multi-objective optimization techniques, and the integration of advanced technologies such as soft open points (SOPs) to enhance grid stability and efficiency. The paper categorizes these strategies into two main types: analytical methods and computational methods. In conclusion, this review underscores the critical need for advanced analytical and computational methods in the voltage regulation of ADNs with high renewable energy penetration levels, highlighting the potential for significant improvements in grid stability and efficiency. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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28 pages, 3805 KiB

Open AccessReview

A Review of Passive Solar Heating and Cooling Technologies Based on Bioclimatic and Vernacular Architecture

by Julia Lima Toroxel and Sandra Monteiro Silva

Energies 2024, 17(5), 1006; https://doi.org/10.3390/en17051006 - 21 Feb 2024

Cited by 4 | Viewed by 3870

Abstract

The increase in global average temperature, mainly due to the high rate of greenhouse gas emissions, has triggered severe global warming and climate change. In Europe, the building sector accounts for a significant portion of emissions and energy consumption, prompting attention on nearly-zero-energy [...] Read more.

The increase in global average temperature, mainly due to the high rate of greenhouse gas emissions, has triggered severe global warming and climate change. In Europe, the building sector accounts for a significant portion of emissions and energy consumption, prompting attention on nearly-zero-energy buildings (nZEBs) and zero-carbon buildings, as they play a pivotal role in reaching the goal of climate neutrality by 2050. Passive systems offer a promising solution, optimizing energy usage by better adapting buildings to their local climates. This paper reviews the state-of-the-art of passive heating and cooling techniques, exploring their contributions to contemporary architecture and showcasing their features and adaptability across different climates. Furthermore, the link between traditional and bioclimatic architecture is assessed. Recent years have witnessed a surge in publications on bioclimatic solar passive strategies, reflecting an intensified debate on climate change. Europe leads research in this area, aligned with initiatives like the Green Deal and Fit for 55. While dynamic simulation software is widely utilized for energy efficiency analysis, there remains limited integration of Building Information Modeling (BIM) and life cycle analysis (LCA) tools, which could enhance holistic assessments. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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30 pages, 1662 KiB

Open AccessReview

Current Source Inverter (CSI) Power Converters in Photovoltaic Systems: A Comprehensive Review of Performance, Control, and Integration

by Fabrizio Marignetti, Roberto Luigi Di Stefano, Guido Rubino and Roberto Giacomobono

Energies 2023, 16(21), 7319; https://doi.org/10.3390/en16217319 - 28 Oct 2023

Cited by 2 | Viewed by 5427

Abstract

Grid converters play a central role in renewable energy conversion. Among all inverter topologies, the current source inverter (CSI) provides many advantages and is, therefore, the focus of ongoing research. This review demonstrates how CSIs can play a pivotal role in ensuring the [...] Read more.

Grid converters play a central role in renewable energy conversion. Among all inverter topologies, the current source inverter (CSI) provides many advantages and is, therefore, the focus of ongoing research. This review demonstrates how CSIs can play a pivotal role in ensuring the seamless conversion of solar-generated energy with the electricity grid, thereby facilitating stable and reliable integration. This study extensively investigates various categories of single-stage CSI photovoltaic inverters, categorizing them into two-level, three-level, and multi-level architectures. Furthermore, these inverters are classified based on construction attributes, power factor, and total harmonic distortion values to assess their compliance with the standards, such as IEEE 1547 and IEC 61727. This review also delves into diverse control strategies for seamless grid integration. This comprehensive assessment serves as a resource for researchers in the field, enabling them to effectively choose the most suitable CSI for their specific applications. Additionally, it offers a quick reference point to steer research endeavors toward refining the integration of CSIs within photovoltaic systems. Full article

(This article belongs to the Special Issue Modern Technologies for Renewable Energy Development and Utilization II)

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