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Malaysia, as one of the highest producers of palm oil globally and one of the largest exporters, has a huge potential to use palm oil waste to generate electricity since an abundance of waste is produced during the palm oil extraction process. This research aims to investigate the potential electricity generation using palm oil waste and the feasibility of implementing the technology in rural areas. To implement and analyze the feasibility, a case study has been carried out in a rural area in Sarawak, Malaysia. By collecting data through questionnaires and surveys, an analysis has been carried out to determine the approximate cost and quantity of palm oil waste to generate cheaper renewable energy. We concluded that electricity generation from palm oil waste is cost-effective and beneficial.
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  • Open AccessOpen Access

    ARTICLE

    A Feasibility Study of Renewable Energy Generation from Palm Oil Waste in Malaysia

    Mujahid Tabassum1,*, Md. Bazlul Mobin Siddique2, Hadi Nabipour Afrouzi3, Saad Bin Abdul Kashem4
    Energy Engineering, Vol.122, No.9, pp. 3433-3457, 2025, DOI:10.32604/ee.2025.065955 - 26 August 2025
    (This article belongs to the Special Issue: Advances in Renewable Energy Systems: Integrating Machine Learning for Enhanced Efficiency and Optimization)
    Abstract Malaysia, as one of the highest producers of palm oil globally and one of the largest exporters, has a huge potential to use palm oil waste to generate electricity since an abundance of waste is produced during the palm oil extraction process. In this paper, we have first examined and compared the use of palm oil waste as biomass for electricity generation in different countries with reference to Malaysia. Some areas with default accessibility in rural areas, like those in Sabah and Sarawak, require a cheap and reliable source of electricity. Palm oil waste possesses… More >

  • Open AccessOpen Access

    ARTICLE

    Simulation Platform for the Optimal Configuration of Hybrid Energy Storage Assisting Thermal Power Units in Secondary Frequency Regulation

    Cuiping Li1, Ziyun Zong1, Xingxu Zhu1, Zheng Fang2, Caiqi Jia3, Wenbo Si4, Gangui Yan1, Junhui Li1,*
    Energy Engineering, Vol.122, No.9, pp. 3459-3485, 2025, DOI:10.32604/ee.2025.066629 - 26 August 2025
    (This article belongs to the Special Issue: Integration of Hybrid Renewable Energy Systems for Sustainable Development)
    Abstract In response to the issue of determining the appropriate capacity when hybrid energy storage systems (HESS) collaborate with thermal power units (TPU) in the system’s secondary frequency regulation, a configuration method for HESS based on the analysis of frequency regulation demand analysis is proposed. And a corresponding simulation platform is developed. Firstly, a frequency modulation demand method for reducing the frequency modulation losses of TPU is proposed. Secondly, taking into comprehensive consideration that flywheel energy storage features rapid power response and battery energy storage has the characteristic of high energy density, a coordinated control strategy… More >

    Graphic Abstract

    Simulation Platform for the Optimal Configuration of Hybrid Energy Storage Assisting Thermal Power Units in Secondary Frequency Regulation

  • Open AccessOpen Access

    ARTICLE

    Unravelling Temperature Profile through Bifacial PV Modules via Finite Difference Method: Effects of Heat Internal Generation Due to Spectral Absorption

    Khadija Ibaararen, Mhammed Zaimi, Khadija El Ainaoui, El Mahdi Assaid*
    Energy Engineering, Vol.122, No.9, pp. 3487-3505, 2025, DOI:10.32604/ee.2025.067422 - 26 August 2025
    (This article belongs to the Special Issue: Modelling, Optimisation and Forecasting of Photovoltaic and Photovoltaic thermal System Energy Production)
    Abstract This study investigates the complex heat transfer dynamics in multilayer bifacial photovoltaic (bPV) solar modules under spectrally resolved solar irradiation. A novel numerical model is developed to incorporate internal heat generation resulting from optical absorption, grounded in the physical equations governing light-matter interactions within the module’s multilayer structure. The model accounts for reflection and transmission at each interface between adjacent layers, as well as absorption within individual layers, using the wavelength-dependent dielectric properties of constituent materials. These properties are used to calculate the spectral reflectance, transmittance, and absorption coefficients, enabling precise quantification of internal heat… More >

  • Open AccessOpen Access

    ARTICLE

    Numerical Simulation of Air-Assisted Heating for Cold-Start in Cathode-Open Proton Exchange Membrane Fuel Cells

    Wei Shi1,2, Shusheng Xiong1,2,3,*, Wei Li2,3, Kai Meng4, Qingsheng Liu4
    Energy Engineering, Vol.122, No.9, pp. 3507-3523, 2025, DOI:10.32604/ee.2025.065579 - 26 August 2025
    Abstract In the realm of all-electric aircraft research, the integration of cathode-open proton exchange membrane fuel cells (PEMFC) with lithium batteries as a hybrid power source for small to medium-sized unmanned aerial vehicles (UAVs) has garnered significant attention. The PEMFC, serving as the primary energy supply, markedly extends the UAV’s operational endurance. However, due to payload limitations and spatial constraints in the airframe layout of UAVs, the stack requires customized adaptation. Moreover, the implementation of auxiliary systems to facilitate cold starts of the PEMFC under low-temperature conditions is not feasible. Relying solely on thermal insulation measures… More >

  • Open AccessOpen Access

    REVIEW

    Thermo-Hydrodynamic Characteristics of Hybrid Nanofluids for Chip-Level Liquid Cooling in Data Centers: A Review of Numerical Investigations

    Yifan Li1, Congzhe Zhu1, Zhihan Lyu2,*, Bin Yang1,3,*, Thomas Olofsson3
    Energy Engineering, Vol.122, No.9, pp. 3525-3553, 2025, DOI:10.32604/ee.2025.067902 - 26 August 2025
    (This article belongs to the Special Issue: Advancements in Energy Efficiency and Thermal Management for Data Center)
    Abstract The growth of computing power in data centers (DCs) leads to an increase in energy consumption and noise pollution of air cooling systems. Chip-level cooling with high-efficiency coolant is one of the promising methods to address the cooling challenge for high-power devices in DCs. Hybrid nanofluid (HNF) has the advantages of high thermal conductivity and good rheological properties. This study summarizes the numerical investigations of HNFs in mini/micro heat sinks, including the numerical methods, hydrothermal characteristics, and enhanced heat transfer technologies. The innovations of this paper include: (1) the characteristics, applicable conditions, and scenarios of… More >

  • Open AccessOpen Access

    ARTICLE

    A Low Common-Mode Voltage Virtual Space Vector Modulation of Three-Level Converters for Doubly-Fed Variable-Speed Pumped Storage Systems

    Ziqiang Man1, Lei Zhao2, Zheng Tao1, Shiming Cheng2, Wei Yan1, Gaoyue Zhong1, Yu Lu1, Wenming Zhang3, Li Zhang3,*
    Energy Engineering, Vol.122, No.9, pp. 3555-3572, 2025, DOI:10.32604/ee.2025.067027 - 26 August 2025
    Abstract With the rapid integration of renewable energy sources, modern power systems are increasingly challenged by heightened volatility and uncertainty. Doubly-fed variable-speed pumped storage units (DFVS-PSUs) have emerged as promising technologies for mitigating grid oscillations and enhancing system flexibility. However, the excitation converters in DFVS-PSUs are prone to significant issues such as elevated common-mode voltage (CMV) and neutral-point voltage (NPV) fluctuations, which can lead to electromagnetic interference and degrade transient performance. To address these challenges, an optimized virtual space vector pulse width modulation (OVSVPWM) strategy is proposed, aiming to suppress CMV and NPV simultaneously through coordinated… More >

  • Open AccessOpen Access

    ARTICLE

    Second-Life Battery Energy Storage System Capacity Planning and Power Dispatch via Model-Free Adaptive Control-Embedded Heuristic Optimization

    Chuan Yuan1, Chang Liu2,3, Shijun Chen1, Weiting Xu2,3, Jing Gou1, Ke Xu2,3, Zhengbo Li4,*, Youbo Liu4
    Energy Engineering, Vol.122, No.9, pp. 3573-3593, 2025, DOI:10.32604/ee.2025.067785 - 26 August 2025
    (This article belongs to the Special Issue: Construction and Control Technologies of Renewable Power Systems Based on Grid-Forming Energy Storage)
    Abstract The increasing penetration of second-life battery energy storage systems (SLBESS) in power grids presents substantial challenges to system operation and control due to the heterogeneous characteristics and uncertain degradation patterns of repurposed batteries. This paper presents a novel model-free adaptive voltage control-embedded dung beetle-inspired heuristic optimization algorithm for optimal SLBESS capacity configuration and power dispatch. To simultaneously address the computational complexity and ensure system stability, this paper develops a comprehensive bilevel optimization framework. At the upper level, a dung beetle optimization algorithm determines the optimal SLBESS capacity configuration by minimizing total lifecycle costs while incorporating… More >

  • Open AccessOpen Access

    ARTICLE

    Analysis of the Use of Geothermal Energy for Heating in Azerbaijan

    Orkhan Jafarli*
    Energy Engineering, Vol.122, No.9, pp. 3595-3608, 2025, DOI:10.32604/ee.2025.067982 - 26 August 2025
    (This article belongs to the Special Issue: Integrated Renewable Energy Systems for Heating, Cooling, Power Generation and Energy Management)
    Abstract This study investigates the feasibility and efficiency of geothermal energy for heating applications in Azerbaijan, with a specific focus on the Khachmaz region. Despite the country’s growing interest in sustainable energy, limited research has addressed the potential of ground-source heat pump (GSHP) systems under local climatic and soil conditions. To address this gap, the study employs GeoT*SOL simulation to evaluate system performance, incorporating site-specific parameters such as soil thermal conductivity, heating demand profiles, and regional weather data. The results show that the GSHP system achieves a maximum seasonal performance factor (SPF) of 5.62 and an… More >

  • Open AccessOpen Access

    ARTICLE

    The Design and Implementation of a Biomechanics-Driven Structural Safety Monitoring System for Offshore Wind Power Step-Up Stations

    Ruigang Zhang1,*, Qihui Yan2, Jialiang Wang1, Hao Wang1, Jie Sun2, Junjiao Shi2
    Energy Engineering, Vol.122, No.9, pp. 3609-3624, 2025, DOI:10.32604/ee.2025.066880 - 26 August 2025
    (This article belongs to the Special Issue: Advances in Grid Integration and Electrical Engineering of Wind Energy Systems: Innovations, Challenges, and Applications)
    Abstract As the core facility of offshore wind power systems, the structural safety of offshore booster stations directly impacts the stable operation of entire wind farms. With the global energy transition toward green and low-carbon goals, offshore wind power has emerged as a key renewable energy source, yet its booster stations face harsh marine environments, including persistent wave impacts, salt spray corrosion, and equipment-induced vibrations. Traditional monitoring methods relying on manual inspections and single-dimensional sensors suffer from critical limitations: low efficiency, poor real-time performance, and inability to capture millinewton-level stress fluctuations that signal early structural fatigue.… More >

  • Open AccessOpen Access

    ARTICLE

    Mechanistic Investigation of Capacity Degradation in Lithium Iron Phosphate Batteries under Low Temperature Cycling Conditions

    Jianwei Sun, Shuqing Guo*, Shikai Li
    Energy Engineering, Vol.122, No.9, pp. 3625-3646, 2025, DOI:10.32604/ee.2025.067159 - 26 August 2025
    Abstract Since lithium-ion batteries have been put into use, the recession of work cycle efficiency at low temperatures has received widespread attention. In this paper, we investigated the effect of low temperature (−5°C, 0°C, 5°C) environments on the performance of lithium-ion batteries, which are well-known for their excellent discharge performance, cycle life, and safety. However, lithium-ion batteries exhibit significant capacity degradation at low temperatures, especially at 0°C, losing availability after only 10 cycles. Therefore, we conducted cycle degradation tests at 1C discharge and 100% charge-discharge conditions. In this paper, we analyzed the surface morphology, structure, and More >

    Graphic Abstract

    Mechanistic Investigation of Capacity Degradation in Lithium Iron Phosphate Batteries under Low Temperature Cycling Conditions

  • Open AccessOpen Access

    ARTICLE

    Low-Carbon Game Synergistic Strategy for Multi-Park Hydrogen-Doped Integrated Energy System Accessing to Active Distribution Network Based on Dynamic Carbon Baseline Price

    Xin Zhang1,*, Shixing Zhang1, Lina Chen2, Jihong Zhang1, Peihong Yang1, Zilei Zhang1, Xiaoming Zhang1
    Energy Engineering, Vol.122, No.9, pp. 3647-3679, 2025, DOI:10.32604/ee.2025.067035 - 26 August 2025
    Abstract A park hydrogen-doped integrated energy system (PHIES) can maximize energy utilization as a system with multiple supplies. To realize win-win cooperation between the PHIES and active distribution network (ADN), the cooperative operation problem of multi-PHIES connected to the same ADN is studied. A low-carbon hybrid game coordination strategy for multi-PHIES accessing ADN based on dynamic carbon base price is proposed in the paper. Firstly, multi-PHIES are constructed to form a PHIES alliance, including a hydrogen-doped gas turbine (HGT), hydrogen-doped gas boiler (HGB), power to gas and carbon capture system (P2G-CCS), and other equipment. Secondly, a… More >

    Graphic Abstract

    Low-Carbon Game Synergistic Strategy for Multi-Park Hydrogen-Doped Integrated Energy System Accessing to Active Distribution Network Based on Dynamic Carbon Baseline Price

  • Open AccessOpen Access

    ARTICLE

    A Two-Layer Energy Management Strategy for Fuel Cell Ships Considering the Performance Consistency of Fuel Cells

    Yi Zhang1, Diju Gao1,*, Yide Wang2, Zhaoxia Huang3
    Energy Engineering, Vol.122, No.9, pp. 3681-3702, 2025, DOI:10.32604/ee.2025.068656 - 26 August 2025
    Abstract Hydrogen fuel cell ships are one of the key solutions to achieving zero carbon emissions in shipping. Multi-fuel cell stacks (MFCS) systems are frequently employed to fulfill the power requirements of high-load power equipment on ships. Compared to single-stack system, MFCS may be difficult to apply traditional energy management strategies (EMS) due to their complex structure. In this paper, a two-layer power allocation strategy for MFCS of a hydrogen fuel cell ship is proposed to reduce the complexity of the allocation task by splitting it into each layer of the EMS. The first layer of… More >

    Graphic Abstract

    A Two-Layer Energy Management Strategy for Fuel Cell Ships Considering the Performance Consistency of Fuel Cells

  • Open AccessOpen Access

    ARTICLE

    The Overcurrent Limiting Method of GF-SVG in a Wind Farm Based on Adaptive Virtual Reactance

    Jikai Chen, Jiawei Wang, Jiayang Zhang, Shuangshuang Yao, Qianxin Li, Haoru Li*
    Energy Engineering, Vol.122, No.9, pp. 3703-3718, 2025, DOI:10.32604/ee.2025.066620 - 26 August 2025
    (This article belongs to the Special Issue: Integrated Technology Development and Application of Wind Power Systems)
    Abstract As a new dynamic reactive power compensator, the grid-forming Static Var Generator (GF-SVG) can not only provide reactive power-voltage support, but also has inertial support capability. It has been experimentally deployed in many wind farms. However, studies have shown that when the three-phase short-circuit fault occurs in the wind farm, the transient overcurrent during the fault occurrence and fault clearance is suppressed, making it difficult for GF-SVG to use traditional fixed virtual impedance. Aiming at the problem, firstly, the influence of virtual reactance on control stability is analyzed using the GF-SVG’s current open-loop transfer function.… More >

  • Open AccessOpen Access

    ARTICLE

    Fault Diagnosis Method for Photovoltaic Grid-Connected Inverters Based on MPA-VMD-PSO BiLSTM

    Jingxian Ni, Chaomeng Wang, Shiqi Sun, Yuxuan Sun, Gang Ma*
    Energy Engineering, Vol.122, No.9, pp. 3719-3736, 2025, DOI:10.32604/ee.2025.066971 - 26 August 2025
    Abstract To improve the fault diagnosis accuracy of a PV grid-connected inverter, a PV grid-connected inverter data diagnosis method based on MPA-VMD-PSO-BiLSTM is proposed. Firstly, unlike the traditional VMD algorithm which relies on manual experience to set parameters (e.g., noise tolerance, penalty parameter, number of decompositions), this paper achieves adaptive optimization of parameters through MPA algorithm to avoid the problem of feature information loss caused by manual parameter tuning, and adopts the improved VMD algorithm for feature extraction of DC-side voltage data signals of PV-grid-connected inverters; and then, adopts the PSO algorithm for the Then, the… More >

  • Open AccessOpen Access

    ARTICLE

    A Non-Unit Protection Based on Propagation of Fault Traveling Wave for Transmission Line Connected to Wind Power Plant

    Hao Wang*, Wenyue Zhou, Yiping Luo
    Energy Engineering, Vol.122, No.9, pp. 3737-3752, 2025, DOI:10.32604/ee.2025.067938 - 26 August 2025
    (This article belongs to the Special Issue: Integrated Technology Development and Application of Wind Power Systems)
    Abstract Currently, renewable energy has been broadly implemented across diverse sectors, particularly evidenced by its substantially higher integration levels in power systems. The large-scale integration of renewable energy resources introduces distinct fault characteristics into power grids, potentially rendering traditional line protection schemes inadequate for transmission lines interfacing with these sources. Therefore, it is imperative to study line protection methods unaffected by the integration of renewable energy resources. After analyzing the propagation process of the fault traveling wave along the transmission line, a non-unit protection based on traveling wave distance measurement is proposed. The core principle of… More >

  • Open AccessOpen Access

    ARTICLE

    Impact of Building Materials for the Facade on Energy Consumption and Carbon Emissions (Case Study of Residential Buildings in Tehran)

    Amir Sina Darabi*, Mehdi Ravanshadnia
    Energy Engineering, Vol.122, No.9, pp. 3753-3792, 2025, DOI:10.32604/ee.2025.065241 - 26 August 2025
    (This article belongs to the Special Issue: Innovative Strategies for Energy-Efficient Buildings in a Sustainable Future)
    Abstract Although currently, a large part of the existing buildings is considered inefficient in terms of energy, the ability to save energy consumption up to 80% has been proven in residential and commercial buildings. Also, carbon dioxide is one of the most important greenhouse gases contributing to climate change and is responsible for 60% of global warming. The facade of the building, as the main intermediary between the interior and exterior spaces, plays a significant role in adjusting the weather conditions and providing thermal comfort to the residents. In this research, 715 different scenarios were defined… More >

  • Open AccessOpen Access

    ARTICLE

    Low-Carbon Economic Dispatch Strategy for Integrated Energy Systems with Blue and Green Hydrogen Coordination under GHCT and CET Mechanisms

    Aidong Zeng1,2,*, Zirui Wang1, Jiawei Wang 3, Sipeng Hao1,2, Mingshen Wang4
    Energy Engineering, Vol.122, No.9, pp. 3793-3816, 2025, DOI:10.32604/ee.2025.069410 - 26 August 2025
    (This article belongs to the Special Issue: Revolution in Energy Systems: Hydrogen and Beyond)
    Abstract With the intensification of the energy crisis and the worsening greenhouse effect, the development of sustainable integrated energy systems (IES) has become a crucial direction for energy transition. In this context, this paper proposes a low-carbon economic dispatch strategy under the green hydrogen certificate trading (GHCT) and the ladder-type carbon emission trading (CET) mechanism, enabling the coordinated utilization of green and blue hydrogen. Specifically, a proton exchange membrane electrolyzer (PEME) model that accounts for dynamic efficiency characteristics, and a steam methane reforming (SMR) model incorporating waste heat recovery, are developed. Based on these models, a… More >

    Graphic Abstract

    Low-Carbon Economic Dispatch Strategy for Integrated Energy Systems with Blue and Green Hydrogen Coordination under GHCT and CET Mechanisms

  • Open AccessOpen Access

    ARTICLE

    A Fault Location Method of Multi-Branch Distribution Line Based on MODWT Combined with Improved TEO

    Pan Duan*, Enze Peng
    Energy Engineering, Vol.122, No.9, pp. 3817-3838, 2025, DOI:10.32604/ee.2025.066491 - 26 August 2025
    Abstract To address the challenges of fault line identification and low detection accuracy of wave head in Fault Location (FL) research of distribution networks with complex topologies, this paper proposes an FL method of Multi-Branch distribution line based on Maximal Overlap Discrete Wavelet Transform (MODWT) combined with the improved Teager Energy Operator (TEO). Firstly, the current and voltage Traveling Wave (TW) signals at the head of each line are extracted, and the fault-induced components are obtained to determine the fault line by analyzing the polarity of the mutation amount of fault voltage and current TWs. Subsequently,… More >

  • Open AccessOpen Access

    ARTICLE

    Impact of Duty Cycling HVAC Systems on Thermal Comfort, Energy Consumption, and Operational Costs

    Alya Penta Agharid1, Indra Permana2, Linlan Chang1, Yi-Han Luo2, Fujen Wang2,*
    Energy Engineering, Vol.122, No.9, pp. 3839-3866, 2025, DOI:10.32604/ee.2025.068586 - 26 August 2025
    (This article belongs to the Special Issue: Innovative Strategies for Energy-Efficient Buildings in a Sustainable Future)
    Abstract Air conditioning (AC) is essential for maintaining indoor comfort during Taiwan’s hot and humid summers but significantly contributes to increased energy consumption. This study evaluates the effects of AC duty-cycling strategies on energy performance, thermal comfort, and operational costs in office environments. Duty-cycling was implemented using a building energy management system (BEMS), which remotely controlled the ON/OFF cycles of AC units. Five duty-cycling modes were tested, with some modes incorporating air circulation during OFF periods. Field measurements of energy consumption, temperature, humidity, and air velocity were conducted and integrated with thermal comfort analysis tools to… More >

  • Open AccessOpen Access

    ARTICLE

    Bi-Level Collaborative Optimization of Electricity-Carbon Integrated Demand Response for Energy-Intensive Industries under Source-Load Interaction

    Huaihu Wang1, Wen Chen2, Jin Yang1, Rui Su1, Jiale Li3, Liao Yuan3, Zhaobin Du3,*, Yujie Meng3
    Energy Engineering, Vol.122, No.9, pp. 3867-3890, 2025, DOI:10.32604/ee.2025.068062 - 26 August 2025
    (This article belongs to the Special Issue: Integration of Renewable Energies with the Grid: An Integrated Study of Solar, Wind, Storage, Electric Vehicles, PV and Wind Materials and AI-Driven Technologies)
    Abstract Traditional demand response (DR) programs for energy-intensive industries (EIIs) primarily rely on electricity price signals and often overlook carbon emission factors, limiting their effectiveness in supporting low-carbon transitions. To address this challenge, this paper proposes an electricity–carbon integrated DR strategy based on a bi-level collaborative optimization framework that coordinates the interaction between the grid and EIIs. At the upper level, the grid operator minimizes generation and curtailment costs by optimizing unit commitment while determining real-time electricity prices and dynamic carbon emission factors. At the lower level, EIIs respond to these dual signals by minimizing their… More >

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