Abdellah Idrissi^1,*, Elbachir Abddaim^2,3, Hicham El Mghari¹, Rachid El Amraoui¹, Siham Sakami⁴, Lahcen Boukhattem^2,3, Brahim Addou¹

Energy Engineering, Vol.123, No.10, 2026, DOI:10.32604/ee.2026.083896 - 30 August 2026

Abstract This study numerically investigates the influence of inlet–outlet arrangement on the thermo-hydraulic performance of a thermocline thermal energy storage (TES) tank using three-dimensional transient CFD simulations in ANSYS Fluent. Four different inlet–outlet configurations were analyzed under identical discharge conditions to evaluate their effects on thermal stratification, discharge efficiency, and internal flow behavior. The numerical model was developed using the continuity, momentum, and energy equations with the Boussinesq approximation and validated against reference experimental data with deviations below 5%. The results showed that the inlet–outlet arrangement significantly affects thermocline evolution and thermal mixing inside the storage More > Graphic Abstract

Ruanming Huang¹, Yuchen Qi¹, Yaoliang Zhu¹, Chen Qian¹, Haojie Li^2,*, Bing Wang²

Energy Engineering, Vol.123, No.10, 2026, DOI:10.32604/ee.2026.083133 - 30 August 2026

Abstract With the continuous expansion of installed capacity of renewable energy represented by wind power, modern power systems are increasingly characterized by high penetration of power electronics. This trend leads to reduced system inertia and compromised disturbance resilience, posing prominent challenges to frequency stability. Mainstream wind turbines operating in maximum power point tracking (MPPT) mode typically lack effective responses to system frequency fluctuations. Although conventional fixed-parameter virtual synchronous generator (VSG) technology can provide inertial support, it struggles to balance dynamic response speed and operational stability under variable operating conditions. To address these issues, this paper proposes… More >

Erman Taer^1,*, Novi Yanti¹, Asmarwati¹, Apriwandi¹, Abrar Ismardi², Indra Wahyudhin Fathona², Memoria Rosi², Bidayatul Armynah³, Dahlang Tahir³, Ninis Hadi Haryanti⁴, Suryajaya⁴, Isnasyauqiah⁵, Ida Usman⁶, Julnaidi⁷, Rika Taslim^8,*

Journal of Renewable Materials, Vol.14, No.8, 2026, DOI:10.32604/jrm.2026.02026-0022 - 26 August 2026

Abstract The promotion of bio-carbon for developing superior electrodes has become a trending topic in realising the practical application of supercapacitor devices. This study aimed to prepare porous carbon (PC) with a taproot fiber-like nanostructure that was decorated with self-doped oxygen. The waste of red suren leaves (RSL) was further treated using a direct heating method with the catalyst effect of ZnCl₂ (0.3, 0.5, and 0.7 M) in an N₂/CO₂ environment at 850°C, being examined. The results showed that RSL@PC-0.5 exhibited the best amorphous carbon structure (FWHM = 0.105° and 0.182°). The specific surface area (SSA =… More > Graphic Abstract

Fatin Nadhirah¹, Surajudeen Sikiru^1,2,*, Mohd Muzamir Mahat^1,3

Energy Engineering, Vol.123, No.9, 2026, DOI:10.32604/ee.2026.082624 - 06 August 2026

Abstract Agricultural waste has received increased attention as a sustainable precursor for activated carbon manufacture because of its availability, inexpensive price, and ecological benefits. However, the search for the right biomass and optimization of the activation process remain one of the major challenges in the production of high-performance composites in energy storage applications. In this study, pyrolysis of durian and eggshells was performed for activated carbon production using sodium sulfite (Na₂SO₃) and orthophosphoric acid (H₃PO₄) as activating agents, then combined both together with a ratio of 1:1 to produce a hybrid activated carbon to increase the performance… More >

Yiqun Kang^1,*, Zhe Li¹, Li You¹, Haozhe Xiong², Yuxuan Hu³, Fei Wang^4,*

Energy Engineering, Vol.123, No.9, 2026, DOI:10.32604/ee.2026.078724 - 06 August 2026

Abstract As the world’s energy framework shifts towards a low-carbon model, the widespread incorporation of renewable energy (RE) sources, primarily wind power and photovoltaics (PV), into the power grid is an unavoidable development. The micro-energy grid (MEG), as an integrated system that combines distributed energy, energy storage (ES), and power loads, can achieve efficient consumption of RE by implementing multi-machine optimal allocation and unified coordinated power control for parallel operation of grid-forming energy storage (GFES). For this purpose, this paper puts forward a low-carbon and economic dispatch strategy for MEG that considers multi-machine optimal allocation of… More >

Jiyuan Liao¹, Jiangyan Zhao^2,*, Xin Li³, Changmao Liu¹, Banghong Tang¹, Zihan Ling³

Energy Engineering, Vol.123, No.9, 2026, DOI:10.32604/ee.2025.074667 - 06 August 2026

Abstract To address the uncertainty and volatility of renewable energy while meeting the requirements of low-carbon economic operation, this paper proposes a two-stage robust optimal dispatch model for an integrated wind-solar-hydro-thermal-storage energy system with coupled power-to-gas (P2G) and carbon capture system (CCS). First, a mathematical model of the integrated wind-solar-hydro-thermal-storage energy system with P2G-CCS coupling is developed to promote internal carbon cycling and enhance the capability to accommodate renewable energy. Second, the scheduling problem is formulated as a two-stage robust optimization model. A cardinality-based uncertainty set is adopted to model deviations in renewable energy output, and… More >

Qiang Liu¹, Yongqiang Zhou¹, Chaoyang Lu², Zhen Yan¹, Gangui Yan², Cheng Yang^2,*, Yupeng Wang²

Energy Engineering, Vol.123, No.9, 2026, DOI:10.32604/ee.2025.073028 - 06 August 2026

Abstract The increasing proportion of power generated by new energy has meant that grid-forming energy storage has become a key method for improving power grid flexibility. However, the small disturbance stability problem has become an important challenge. The issue is that grid-forming energy storage is prone to low-frequency oscillation under strong grid conditions. Therefore, this study proposes a multi damping torque model to analyze the small signal stability of grid-forming energy storage converters. The impact of grid strength, operating conditions, and control parameters on the damping characteristics of the low-frequency oscillation by the system was quantitatively More >

Ikenna D. Arungwa^1,2,*, Elochukwu C. Moka²

Revue Internationale de Géomatique, Vol.35, pp. 423-459, 2026, DOI:10.32604/rig.2026.083164 - 29 July 2026

Abstract This study utilized nearly two decades of temporal gravity field observations from the Gravity Recovery and Climate Experiment (GRACE/GRACE-FO) satellite missions to analyze the spatial and temporal variations of terrestrial water storage (TWS) and groundwater storage (GWS) in Nigeria. Advanced statistical techniques, including Singular Spectrum Analysis (SSA), Principal Component Analysis (PCA), and Empirical Orthogonal Function (EOF), were applied to characterize and quantify these variations at a basin scale. Results show that TWS exhibits biennial, annual seasonal fluctuations (between ±10 to ±55 mm), reaching its lowest levels during the dry season (February–June) and peaking in the… More >

Alireza Norouzpour Shahrbejari¹, Nafiseh Pishbin², Mohammad Reza Maghami^3,*, Mazlan Mohamed^4,*, Mohammad Golmohammad¹

CMES-Computer Modeling in Engineering & Sciences, Vol.148, No.1, 2026, DOI:10.32604/cmes.2026.083763 - 27 July 2026

Abstract This study presents a weighted-sum multi-criteria optimization framework using PSO for the optimal siting, sizing, and scenario-based operation of energy storage systems (ESSs) in renewable-integrated distribution networks. The proposed model concurrently addresses technical, economic, and reliability objectives—minimizing active power losses (PL), voltage deviation (VD), expected energy not supplied (EENS), and short-circuit level (SCL), while maximizing voltage sensitivity index (VSI) and power-loss sensitivity factor (PLSF). A Particle Swarm Optimization (PSO) algorithm with weighted-sum scalarization is employed to solve this complex, nonlinear optimization problem and effectively balance the conflicting operational goals. The framework is validated using IEEE… More >

Rukun Hu¹, Liao Zhang¹, Wenbin Han¹, Wei Chen¹, Bo Ma¹, Xuan Liu¹, Yongzhi Lei¹, Qian Lu¹, Yuanji Li², Xiaohu Yang^2,*

Frontiers in Heat and Mass Transfer, Vol.24, No.3, 2026, DOI:10.32604/fhmt.2026.081154 - 29 June 2026

Abstract To enhance the efficiency of phase change heat storage, this study investigates the synergistic effects and parameter interactions of a coupled strategy integrating fins, metal foam, and nanoparticles. A validated numerical model is developed for a shell-and-tube heat storage unit. The influence of porosity and pore density of metal foam, as well as Al₂O₃ nanoparticle concentration, on melting behavior, heat storage rate, and fluid flow features are systematically analyzed. Results indicate that reducing porosity significantly enhances heat conduction, shortening the complete melting time by up to 53.71%. Conversely, increasing pore density markedly suppresses natural convection, reducing… More >