Search Results (4,348)

The high energy consumption of conventional mixers equipped with active mixing elements necessitates the development of more efficient technologies for mixing bulk materials and feed mixtures. This study presents a gravity-driven mixing approach based on the rotation of an inclined cylindrical chamber, eliminating the need for active mixing elements. During chamber rotation, the mixture components move toward both end walls while simultaneously undergoing a circular motion along the inner cylindrical surface. This movement intensifies the mixing process and reduces energy consumption, thereby providing an energy-efficient gravity-based mixing approach that operates without active mixing elements. Laboratory experiments were conducted to determine the key physical and mechanical properties of the sapropel, organic fertilizer, and compound feed (formulation K-60-1). The measured values were as follows: velocity on an inclined steel surface, 0.65–1.21 m/s; coefficient of friction, 0.40–0.91; bulk density, 453–1166 kg/m³; and angle of repose, 36–39°. The experimental results confirmed the validity and adequacy of the developed analytical relationships. A structural and technological design of the gravity mixer was developed, and an experimental prototype was manufactured. Analytical relationships were obtained to determine the critical rotational speed of the chamber, particle movement velocity, and the power required for the mixing process. Under optimal operating conditions, the mixture uniformity reached 95.7% after 4 min of mixing. The mixer productivity was 0.95 t/h, while the specific energy consumption was 0.5 kWh/t, which is 2.5 times lower than that of conventional mixers equipped with active mixing elements. The obtained results confirm the feasibility and effectiveness of the proposed gravity-based mixing method for the preparation of feed and organomineral mixtures under the operating conditions of small-scale farms. Full article

Greenhouse microclimate regulation is challenging due to nonlinear coupling among temperature, humidity, soil moisture, and light intensity, which limits the effectiveness of conventional threshold-based and PID control strategies under time-varying environmental disturbances. This paper presents a forecast-augmented ensemble control framework that combines Random Forest, Gradient Boosting, and Support Vector Machine classifiers with one-hour-ahead weather forecasts for closed-loop greenhouse microclimate regulation. The proposed system was deployed and validated in a working greenhouse cultivating cucumber (cv. ‘Madora F1’) over 28 consecutive days. Sensor measurements and forecast inputs were processed through a unified preprocessing pipeline, while control actions were generated through majority voting and executed on Raspberry Pi 4B edge hardware with a worst-case inference latency below 18 ms. The proposed framework achieved a temperature RMSE of 0.83 °C during field deployment. For reference, RMSE values of 3.21 °C and 1.94 °C were obtained for the threshold-based and PID baseline controllers, respectively, under the adopted disturbance-consistent evaluation protocol. Compliance rates reached 96.4% for temperature, 94.1% for relative humidity, and 97.2% for soil moisture across 40,320 resampled observation intervals (60 s analysis grid) derived from the original 10 s acquisition stream. Integration of short-term weather forecasts enabled anticipatory irrigation management, reducing irrigation pump operation by 18% without compromising soil-moisture compliance and yielding an estimated annual energy saving of 158 kWh per greenhouse zone. Unlike prediction-oriented greenhouse artificial-intelligence studies, the proposed approach implements a deployable forecast-augmented closed-loop control architecture validated under continuous real-world greenhouse operation. Full article

Rural electrification in Sub-Saharan Africa faces a trilemma: cutting carbon emissions, making it economically viable, and achieving fair access to energy for all. This paper develops a multi-objective framework that optimises carbon revenue, net present value (NPV), total energy supply, cooking fuel (firewood and LPG), health costs, and benefit to society. The model uses continuous decision variables: daily energy allocation among four sources (solar, generator, firewood, LPG) to three population groups (men, women, children). The case study is a rural community of 7000 people in Nigeria (Tier 1 energy consumers). Six policy scenarios are considered: baseline, high carbon price, low carbon price, microfinance, government subsidy and community cooperative. This study compared algorithms and identified a hybrid Non-dominated Sorting Genetic Algorithm and Particle Swarm Optimisation II as the most suitable algorithm for solving the formulated optimisation problem. It was found that NPV and unit cost of energy would increase to $175,500 and 26.4 ¢/kWh, respectively, by increasing the price of carbon from $8/ton to $12/ton. Firewood generates health savings and carbon revenue in the range of $4100–$12,270/year. Prices below $8/ton do not induce optimal reconfigurations in the system. The best energy supply (2825 kWh/day) and the lowest unsatisfied demand occur in the government subsidy scenario with the greatest disparity index, displaying an equity-efficiency trade-off. The framework shows that sustainable access to energy can be unlocked using strategic integration of carbon finance, valuation of health benefits and equity constraints. Full article

Global demand for sustainability drives interest in bioenergy from sustainable feedstock. Agro-industrial waste such as brewer’s spent grains (BSG) is an important by-product of brewing. This study provides a comprehensive review of the current technologies of BSG for energy recovery and BSG-based materials for energy storage applications. The latest scientific progress, not only from conventional processes on anaerobic digestion, combustion, gasification, pyrolysis, torrefaction, and hydrothermal liquefaction but also from several integrated technologies, pretreatment methods, and additives/catalysts regarding the improvement of energy efficiency and process sustainability, was reviewed. In addition, the co-feedstock practices (co-combustion, anaerobic co-digestion, hydrothermal co-liquefaction, anaerobic co-fermentation) and co-production were examined. AD of BSG yields about 302 NL CH₄/kg COD, generating roughly 0.39 kWh of electricity/kg BSG and 1.71 MJ of thermal energy/kg BSG. Ultrasonic pretreatment enhances methane production up to four times (107 L CH₄/kg TVS) and reduces CO₂ emissions by 0.083 t CO₂eq/t BSG. Anaerobic co-digestion of BSG with other brewery waste increased the yield up to 88 mL CH₄/g TVS, generated approx. 0.348 kWh/kg TVS electricity, and reduced emissions by 0.114 kg CO₂eq/kg TVS. Bioethanol yields can reach 72%, while biohydrogen generation was up to 5154 mL H₂/g glucose. BSG pyrolysis provides up to 71.8% bio-oil, and its calorific value is 18–25 MJ/kg. BSG-derived activated biocarbon has a notable surface area (1792 m²/g) for lithium–sulfur batteries. The assessment showed that BSG’s transformation into bioenergy and energy storage materials aligns with waste reduction and sustainable development goals. However, future research on combined alternative wastes, integrated technologies, green nanotechnology, and artificial intelligence technology could lead to optimal performance and facilitate their industrial application. Full article

Waste-to-energy (WtE) systems are frequently proposed as complementary waste-management strategies; however, their climate performance depends on the interaction between thermodynamic efficiency, material circularity, and electricity-system characteristics. Existing life-cycle assessments generally provide static comparisons between landfill and WtE but rarely identify the operating conditions under which WtE remains environmentally competitive. To address this gap, a parametric life cycle–energy framework was developed by integrating attributional LCA with an analytical energy model capable of evaluating critical efficiency thresholds under varying recovery rates and electricity-grid conditions. Four representative thermoplastics (PET, HDPE, PP, and LDPE) were evaluated using ReCiPe 2016 Midpoint (H) in SimaPro under Mexican electricity conditions ($E{F}_{\mathrm{grid}}=0.444$ kg CO₂eq/kWh). Results indicate that total life-cycle climate impacts are dominated by upstream polymer production, whereas end-of-life management contributes only marginally to overall GWP. Critical-efficiency analysis revealed strong sensitivity to both recovery rate and electricity-grid carbon intensity. For PET, the minimum efficiency required for WtE to outperform landfill increased from 13.1% to 73.5% across the evaluated scenarios, whereas HDPE remained competitive at efficiencies below 1.3%. Monte Carlo simulations (10,000 realizations) further demonstrated that avoided emissions decline systematically with increasing recovery rates, with LDPE exhibiting the highest mean avoided emissions (1735 kg CO₂eq) and PET the lowest (811 kg CO₂eq). These results demonstrate that WtE climate performance is governed primarily by residual waste availability and electricity-system evolution rather than thermodynamic efficiency alone. Consequently, WtE should be interpreted as a transitional residual-waste management strategy whose long-term climate relevance decreases as material circularity and electricity-grid decarbonization advance. Full article

The conversion of bio-waste into functional energy materials provides a robust platform for addressing both environmental and energy challenges. In this paper, discarded absorbent pads are transformed into carbon-rich frameworks, which is followed by the fabrication of composites through the incorporation of Cu₄SnS₄ (CSS) for dual electrochemical applications. Integrating CSS into the waste-derived carbon matrix induces strong synergistic effects, improving electrical conductivity, increasing active-site availability, and accelerating charge-transfer kinetics. Comprehensive physicochemical analyses confirmed the successful formation of a well-integrated heterostructure composite with favorable structural and surface characteristics. Electrochemical evaluations further demonstrated that CSS-modified carbon exhibits superior bifunctional performance. In a two-electrode configuration, the composite delivers an energy density of 12.08 Wh kg⁻¹ at a power density of 250 W kg⁻¹ along with excellent cycling stability in supercapacitor applications. As an electrocatalyst, it achieves a low overpotential of 268 mV at −10 mA cm⁻² and a small Tafel slope of 75 mV dec⁻¹, reflecting efficient reaction kinetics. The strong durability observed in both systems underscores the structural integrity and long-term operational stability of the material. Overall, this paper advances a sustainable waste-to-resource strategy for fabricating multifunctional carbon-based composites, offering a promising platform for integrated energy-storage and hydrogen-generation technologies. Full article

This study investigates an integrated ecological strategy to reduce electricity consumption in semi-collective housing located in the hot–arid climate of Biskra, Algeria, a region with high solar potential. The research combines photovoltaic (PV) electricity generation with passive thermal insulation using a locally sourced bio-based material derived from date palm fibers. The case study includes 104 dwellings within a residential complex of 350 units. Results show that monocrystalline PV panels (350 W) can produce approximately 479 kWh/panel/year. To meet the total annual electricity demand (504,712 kWh), around 1052 panels are required, corresponding to 1714 m² (13.8%) of the available building envelope. This installation area demonstrates the significant photovoltaic potential of the residential complex under hot–arid climatic conditions. Thermal analysis indicates that integrating a 5 cm palm fiber insulation layer increases thermal resistance from 2.06 to 2.62 m²·°C/W and reduces heat flux from 2.18 to 1.72 W/m². This improvement decreases conductive heat transfer through the envelope by approximately 21%, while numerical simulations indicate indoor temperature reductions of 4–8°C during summer conditions. These findings demonstrate that combining PV systems with bio-based insulation significantly enhances energy efficiency and thermal comfort in residential buildings under desert climatic conditions. Full article

Thermal regulation of electrode materials offers an effective strategy for optimizing electrochemical kinetics in phosphate-based energy-storage systems. In this work, cobalt phosphate (Co₃(PO₄)₂) (CoP) electrodes were directly synthesized on nickel foam through a hydrothermal route and subsequently annealed at different temperatures (300, 400, and 500 °C) to investigate the influence of thermal treatment on structural evolution and supercapacitive behavior. X-ray diffraction confirmed the formation of crystalline CoP, while FESEM analysis revealed a strong dependence of morphology on annealing temperature, with CoP-400 exhibiting a well-developed interconnected plate-like architecture favorable for ion transport. XPS and elemental mapping verified the successful incorporation and uniform distribution of Co, P, and O species. Electrochemical investigations demonstrated that annealing temperature critically governs charge-storage behavior, ion diffusion, and mass transport properties. Among all electrodes, CoP-400 exhibited the best electrochemical performance, delivering a high areal capacitance of 28.62 F/cm² at 20 mA/cm², together with the highest ionic diffusion coefficient, lowest equivalent series resistance (0.39 Ω), and dominant diffusion-controlled charge-storage contribution (89%). Furthermore, CoP-400 retained 84.44% capacitance after 12,000 cycles. An asymmetric supercapacitor assembled using CoP-400//AC achieved an areal capacitance of 302 mF/cm², an energy density (ED) of 0.094 mWh/cm², and excellent cycling stability. These findings highlight annealing-engineered CoP as a promising electrode material for high-performance asymmetric supercapacitors. Full article

This study presents an energy-based assessment of a battery electric sport utility vehicle (SUV) tested under high-altitude and high-gradient real-world conditions in Ambato, Ecuador, at approximately 2500 m above sea level. A low-cost instrumentation setup composed of a Global Navigation Satellite System (GNSS) device, a Fluke 393 FC clamp meter, and an On-Board Diagnostics II (OBD-II) interface was used to evaluate zero, positive, and negative road-gradient conditions in Normal and Sport driving modes. The results show that positive gradients increased the acceleration energy from 0.0454 to 0.0658 kWh in Normal mode and from 0.0351 to 0.0535 kWh in Sport mode. In contrast, negative gradients favored regenerative braking, with Normal mode reaching a net energy balance of $-0.0249$ kWh and a segment-level recovery ratio of 194.38%. This value reflects the contribution of gravitational potential energy. Sport mode showed lower regenerative performance, particularly during uphill operation, where the recovery ratio decreased to 8.96%. These findings demonstrate that low-cost instrumentation can capture representative route-level energy trends and support real-world electric vehicle (EV) energy assessment in topographically complex high-altitude environments. Full article

Large-scale dense-phase carbon dioxide (CO₂) injection is an energy-intensive process in the carbon capture, utilization, and storage (CCUS) value chain. To address insufficient utilization of inlet pressure potential energy and sealing/friction losses of conventional reciprocating pumps under high-base-pressure dense-phase CO₂ transport conditions, this study develops a dense-phase CO₂-oriented structural optimization scheme for a hydraulically driven opposed-piston reciprocating pump based on force-coupling. A dynamic model was established to clarify the in situ recovery mechanism by which inlet pressure potential energy is converted into auxiliary thrust, enabling the drive load to shift from absolute pressure to net pressure difference. Simulation results show that under the rated 8 MPa inlet and 25 MPa discharge condition, the optimized opposed-piston configuration reduces peak driving oil pressure by 31.39% compared with the non-opposed reference configuration. Field reliability operation data show an average normalized specific energy consumption of 0.422 kWh/(MPa·m³) during the selected 24 h continuous operating period. The optimized configuration improves inlet-pressure utilization and reduces hydraulic power demand under high-base-pressure dense-phase CO₂ injection conditions, providing theoretical support and engineering reference for low-energy CCUS injection systems. Full article

Alkaline nickel zinc batteries feature high safety, low cost and eco-friendly characteristics, making them highly promising for large-scale energy storage deployment. However, their practical application is severely constrained by the cathode’s electrical conductivity, available active sites, and cycling stability. Herein, vertical 2D hierarchical flake-like NiCoS_x arrays were in situ grown on nickel foam (NF) via a facile alkali-free solvothermal and in situ sulfidation approach. This highly interconnected and open porous flaky structure significantly shortens the ion diffusion pathways, exposes abundant redox-active sites, and accelerates electron transport, imparting excellent rate performance and superior long-cycle stability to the material. The optimized NiCoS_x/NF electrode achieves a high specific capacity of 323 mAh g⁻¹ at 0.5 A g⁻¹, along with excellent capacity retention capability. Assembled with a commercial Zn anode, the NiCoS_x/NF//Zn full battery delivers 124 mAh g⁻¹ at 3 A g⁻¹, and maintains 112.5% of the initial capacity after 500 cyclic tests. Moreover, the assembled NiCoS_x/NF//Zn full cell possesses a high energy density of 615.2 Wh kg⁻¹ along with a power density of 38.6 kW kg⁻¹ (based on the mass of positive electrode active materials). This unique vertical 2D open hierarchical structure plays a crucial role in enhancing the electrochemical performance of cobalt sulfide cathodes and provides valuable insights for the design of high-performance alkaline zinc-based battery electrodes. Full article

Background/Objectives: A current debate addresses where syntactic Merge primarily resides: the left-hemisphere posterior inferior frontal gyrus (IFG) or the temporo-parietal cortex. For proponents of the former, the temporo-parietal cortex supports more effortful processing; for the latter, the IFG supports integration and conflict resolution. We examine aperiodic activity in processing wh-filler-gap dependencies in French for evidence from network dynamics addressing engagement in syntax across L1 and L2. Methods: We extracted aperiodic activity 1/f components (considering offsets as a reflection of neuronal spiking and exponents as a reflection of excitatory–inhibitory balance) out of power spectrum density at 0.5–40 Hz across occipital and bilateral frontal and temporo-parietal regions of interest (ROIs) in reading. Results: Greater exponents arose in temporo-parietal than frontal ROIs in L1 and L2, with strong spiking and regulation suggested by greater offsets and exponents in the occipital ROI in L2—unlike L1—and with potential modulation by L1–L2 representation overlaps. These patterns suggest distributed cell assemblies for L1 and L2 processing. Increased regulation in temporo-parietal ROIs across L1 and L2 cell assemblies might suggest a structural function across temporo-parietal cortices in syntactic processing. Conclusions: Aperiodic activity reflecting connectivity in L1 and L2 processing supports distinct L1 and L2 cell assemblies, with L2 patterns suggesting potential overlap between L1 and L2 circuit modules. Greater exponents in bilateral temporo-parietal ROIs across L1 and L2 indicate increased regulation, supporting the engagement of lateralized temporo-parietal cortices in computations. These effects are discussed by considering advances in syntactic theory and the biology of language readiness. Full article

Residential energy consumption exhibits substantial behavioral uncertainty and temporal heterogeneity, which pose challenges for demand-side management and residential load profiling. However, existing studies often focus on isolated temporal or spatial scales and predominantly employ hard clustering methods based on geometric distance metrics. To address these limitations, this study proposes a multi-scale residential load profiling framework utilizing the Gaussian Mixture Model (GMM) and nearly three years of hourly electricity consumption data from 13 residential buildings in Vancouver. First, schedule-driven and seasonal variations in residential energy consumption were examined through multi-temporal comparative analyses and paired-sample t-tests. The results indicate statistically significant differences between working-time and non-working-time energy consumption patterns in most buildings (p < 0.001). Second, individual-building clustering was performed to identify long-term intra-building daily load evolution characteristics, revealing 2–5 typical daily profiles across different households. Finally, inter-building clustering identified three representative residential groups characterized by low-energy stable patterns, high-energy intensive patterns, and intermediate commuting-oriented patterns. The average daily energy consumption levels of the three clusters were 13.11 kWh, 36.74 kWh, and 21.61 kWh, respectively. The proposed framework provides a data-driven approach for understanding residential energy-use heterogeneity across multiple scales and offers potential guidance for residential demand-side management and urban low-carbon energy planning. Full article

The increasing penetration of wind generation into autonomous and weakly coupled industrial microgrids requires control strategies that can maintain power-supply reliability under stochastic generation and sharply variable loads. This paper proposes an adaptive corridor-based supervisory control algorithm for a lithium-ion battery energy storage system (BESS) integrated with a wind-turbine generator. The novelty of the method is not the general use of battery storage for power smoothing but a control law that maintains the generator within a predefined active-power corridor while transferring fast and medium-duration imbalances to the battery under state-of-charge, power-limit, and response-delay constraints. Unlike PI-based smoothing, model predictive control, or fixed rule-based switching, the proposed approach uses corridor retention as the primary operating criterion and relies only on directly measurable variables. The model was implemented in MATLAB/Simulink for a 2 MW wind-turbine generator coupled with a 444 kWh/1776 kW lithium-ion battery energy storage system. Field-measurement-based simulation validation was performed in MATLAB/Simulink using industrial load data measured at an autonomous oilfield power plant; the validation scenarios included extracted step disturbances, a real multi-peak load profile, prolonged deficit operation, and a scaled configuration scenario. The algorithm compensated for 86.3–87.4% of short-term load peaks, reduced the standard deviation of generator power from 467 to 98 kW, and decreased recovery time from 6.8 to 1.6 s. Full article

The aim of this study is to provide a preliminary assessment of the feasibility of using a three-arm buoy as a small-scale point-absorber wave energy converter under the moderate hydrodynamic conditions of the Baltic Sea. The analysed concept combines an axisymmetric three-floater geometry with two energy-conversion pathways: an electric generator and a pneumatic energy-storage subsystem based on compressed air. The study defines the geometrical and buoyancy parameters of the structure and applies two complementary modelling levels: a simplified screening-level energy estimate and a first-order heave-response model. The extended analysis includes the influence of effective operational density, added mass, PTO damping, conversion-path efficiency, heave RAO and hydrostatic stability. The baseline screening estimate indicates that the total daily energy output may amount to approximately 0.409 kWh under average wave conditions and approximately 0.920 kWh for higher waves. The first-order heave-response model shows that, for an assumed electrical conversion efficiency of 10%, the daily electrical energy estimate ranges from approximately 0.88 kWh/day for the lightweight configuration to approximately 4.12 kWh/day for the most heavily ballasted analysed case. The RAO analysis indicates that increasing the operational mass shifts the natural period towards longer wave periods, although the system remains outside resonance tuning for the reference wave period of 6 s. The hydrostatic analysis indicates that the three-arm configuration increases the waterplane second moment of area compared with a single circular buoy of the same waterplane area and provides a more directionally balanced stability response. The results should be interpreted as conceptual and parametric estimates rather than experimentally validated wave-to-wire performance. Further work should include BEM/CFD-based hydrodynamic coefficients, irregular-wave modelling, multi-degree-of-freedom dynamics, mooring-system coupling and laboratory validation. Full article