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Self‐charging power systems (SCPSs) are envisioned as promising solutions for emerging electronics to mitigate the increasing global concern about battery waste. However, present SCPSs suffer from large form factors, unscalable fabrication, and material complexity. Herein, a type of highly stable, eco‐friendly conductive inks based on poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) are developed for direct ink writing of multiple components in the SCPSs, including electrodes for miniaturized spacer‐free triboelectric nanogenerators (TENGs) and microsupercapacitors (MSCs), and interconnects. The principle of "one ink, multiple functions" enables to almost fully print the entire SCPSs on the same paper substrate in a monolithic manner without post‐integration. The monolithic fabrication significantly improves the upscaling capability for manufacturing and reduces the form factor of the entire SCPSs (a small footprint area of ≈2 cm × 3 cm and thickness of ≈1 mm). After pressing/releasing the TENGs for ≈79000 cycles, the 3‐cell series‐connected MSC array can be charged to 1.6 V while the 6‐cell array to 3.0 V. On‐paper SCPSs are promising to serve as lightweight, thin, sustainable, and low‐cost power supplies. [ABSTRACT FROM AUTHOR]

This study delves into the dynamic evolution of solids content in a pilot-scale through air drying tissue machine, aiming to enhance comprehension and refine optimization strategies for tissue manufacturing. It focuses on development of solids content throughout the process. Analyzing the interaction between process parameters and solids content provides deeper insights into water removal dynamics. The research employs solid contents monitoring techniques in pilot scale, offering a detailed view of solids content evolution from the wet web's inception to the final tissue product. It significantly highlights the impact of key parameters, particularly pulp refining, on solids content across all positions of the pilot machine. Additionally, the study emphasizes the influence of vacuum system configurations, identifying the relationship between energy expended in the vacuum system and evaporation energy. Furthermore, the results indicate that compression and air displacement dewatering in vacuum boxes are less speed-sensitive compared to heat-driven evaporation in the TAD- and Yankee cylinders. Solid contents at all positions in the tissue machine correlates between various dewatering elements. Optimizing site-specific dewatering and evaporation strategies can potentially save drying energy in the Yankee drying phase which hold promise for enhanced energy and resource utilization, aligning with demands for sustainable manufacturing practices. [ABSTRACT FROM AUTHOR]

Overwintering insects are facing energetic challenges because of food shortage, low temperature, and desiccation stress. Paper wasps of the genus Polistes overwinter as mated adults (gynes) in hibernacula protecting them from predation, snow, and rain but barely from low environmental temperature. In different climates, they face differing overwintering temperature regimes, and therefore they may differ in their energy use. We investigated how much of energy resources built up until autumn is used during diapause dormancy in natural hibernacula by measuring lipid, glycogen, and free carbohydrate content in autumn and early spring in Polistes dominula from temperate European (Austrian) and warm Mediterranean (Italian) climate and Polistes gallicus from Mediterranean climate. Winter energy consumption amounted to ~ 339 and ~ 310 J per wasp in the Austrian and Italian Polistes dominula populations. The smaller Italian Polistes gallicus consumed ~ 247 J. This amounts to 2.62, 2.35, and 1.79 J per day. Of this, the energy demand was mainly fuelled by lipids (84%, 93%, and 90%, respectively), but glycogen stores contributed also considerably (16%, 6%, and 9%). Free carbohydrates decreased only by 0.7%, 1%, and 0.8%. While fat stores seem still sufficient in spring, the wasps depleted most of their carbohydrates. The energy reserves of 396, 400, and 147 J per wasp remaining in spring in the three populations seem sufficient to fuel rest or simple brood care activities for a whole summer but restrict foraging flights to a few hours (~ 3.5–6 h). Results suggest that energy supply might become challenging in expected future climate scenarios. [ABSTRACT FROM AUTHOR]

Micro Fuel cells or microfluidic fuel cells (μMFCs) are one of the most promising power supplies for portable electronics. However, the necessary electrode spacing is required to prevent fuel-crossover and maintain the stable operation, introducing the unavoidable ohmic resistance and retarding the miniaturization. Herein, we propose a novel μMFC device combining the cellulose paper as separator, with selective catalysts at the cathode side to eliminate the unwanted side reactions and increase the system compactness. One single reactant solution containing fuel and electrolyte is applied to keep the device stable operation. The power-generation properties are evaluated in typical alkaline conditions. A great construction simplification makes the device a substantial high-power density of 2.14 W cm−3 and maximum current density of 15.82 A cm−3. The μMFC stacks are arranged in series and parallel manners, which delivers a maximum power output of 23.6 mW and current of 194.6 mA. It is expected that innovative and customizable performance from commercial paper and low-cost carbonaceous catalysts can provide a forum for future advancement in chip-based electrochemical energy generation and storage devices. • Filter paper served as a membrane for μMFC is proposed. • The electrode-pair distance is greatly minimized (∼140 μm). • The optimized μMFC delivers an ultrahigh power density of 2.14 W cm−3. • The μMFC stacks power output of 23.6 mW and current output of 194.6 mA are achievable. [ABSTRACT FROM AUTHOR]

Sustaining life on the Earth with its ever-growing population is forcing changes in people’s way of life, industrial and agricultural production, exploitation of energy resources, and approaches to ecology. We face continual growth in the world’s population, and the demand for materials is growing even more rapidly. Every manufacturing and consumer sector is looking for ways to save energy and materials, attempting to minimize their negative impacts on the environment. In the pulp and paper industry, one of the segments in which progress can be made and help protect the planet is to reduce the brightness of paper. Such a reduction would lead to a lowering in the energy and material costs associated with paper production. [ABSTRACT FROM AUTHOR]

The conversion of ubiquitous hygrothermal resources into renewable energy offers significant potential for cable‐free, self‐powered systems that can operate worldwide without regard to climatic or geographic limitations. Here, an all‐printed flexible hygro‐thermoelectric paper generator is demonstrated that uses bifunctional mobile ions and electrons to make the moist‐diffusion effect, the Soret effect, and the Seebeck effect work synergistically. In the ordinary hygrothermal settings, it generates an unconventional hygro‐thermoelectric output pattern and shows almost a dozen‐fold increase in positive hygro‐thermopower of 26.70 mV K−1 and also another negative hygro‐thermopower of −15.71 mV K−1 compared to pure thermopower. A single paper generator can produce a giant 680 mV displaying typical cyclic sinusoidal waveform characters with volt‐sized amplitudes. The ion‐electron conductive ink is easily printable and consists primarily of a Bi2Te3/PEDOT:PSS thermoelectric matrix modulated with a hygroscopic glycerol that releases ion charges for moist‐diffusion effect and Soret effect, as well as electron charges for Seebeck effect. The emerged hygro‐thermoelectric harvesting strategy from surrounding hygrothermal resources offers a revolutionary approach to the next generation of hybrid energy with cost‐efficiency, flexibility, and sustainability, and also enables large‐scale roll‐to‐roll production. [ABSTRACT FROM AUTHOR]

The large-scale implementation of renewable energy systems necessitates the development of energy storage solutions to effectively manage imbalances between energy supply and demand. Herein, we investigate such a scalable material solution for energy storage in supercapacitors constructed from readily available material precursors that can be locally sourced from virtually anywhere on the planet, namely cement, water, and carbon black. We characterize our carbon-cement electrodes by combining correlative EDS-Raman spectroscopy with capacitance measurements derived from cyclic voltammetry and galvanostatic charge-discharge experiments using integer and fractional derivatives to correct for rate and current intensity effects. Texture analysis reveals that the hydration reactions of cement in the presence of carbon generate a fractal-like electron-conducting carbon network that permeates the load-bearing cement-based matrix. The energy storage capacity of this space-filling carbon black network of the high specific surface area accessible to charge storage is shown to be an intensive quantity, whereas the high-rate capability of the carbon-cement electrodes exhibits self-similarity due to the hydration porosity available for charge transport. This intensive and self-similar nature of energy storage and rate capability represents an opportunity for mass scaling from electrode to structural scales. The availability, versatility, and scalability of these carbon-cement supercapacitors opens a horizon for the design of multifunctional structures that leverage high energy storage capacity, highrate charge/discharge capabilities, and structural strength for sustainable residential and industrial applications ranging from energy autarkic shelters and self-charging roads for electric vehicles, to intermittent energy storage for wind turbines and tidal power stations. [ABSTRACT FROM AUTHOR]

This work describes a direct optical readout of an ion-selective potentiometric sensing array without an external power supply. Electronic paper (e-paper) was chosen as the signal transducer owing to its fast response on the order of seconds and its wide dynamic range of about 1.5 V. The capacitive character of the display allows one to observe the optical response at zero current, which is a desired condition for the potentiometric measurement. An applied potential of 1 V gives a transient charge flow of about 11 μC for the e-paper to exhibit a maximal intensity change. The cathodes of three different pixels of the e-paper were connected to three different ISEs responsive to Na+, K+, and Ca2+, while their common anode was connected to the shared reference electrode (RE). In this manner, each pixel is mapped to the behavior of one sensor, making it possible to detect multiple ions with an e-pixel array. The sensor configuration gave quantitative information on Na+, K+, and Ca2+ from 10−5 M to 10−1 M by analyzing the RGB information of the pixels. The e-paper exhibited a stable response within half a minute, much faster than previously established electrochromic material transducers such as Prussian Blue (PB). With this approach we successfully carried out multi-ion concentration sensing without external power, which is potentially attractive for applications in environmental monitoring, clinical assays and wearable sensing devices. [Display omitted] • A self-powered multi-channel potentiometric sensor array for simultaneous monitoring of potassium, calcium, and sodium. • The rapid optical response of this sensor is adequate for real time monitoring. • Excellent correlation between this approach and direct potentiometry. [ABSTRACT FROM AUTHOR]

Recently, as the use of wearable devices and the demand for eco-friendly energy have increased, many studies have been conducted on triboelectric nanogenerators (TENGs), which can economically harvest energy. Paper is considered a promising substrate and frame material that can be used to manufacture self-powered TENGs, owing to its flexibility, low cost, and accessibility. Herein, we present a sandwich-structured foldable paper-based TENG (FP-TENG) that comprises flexible materials and uses paper as a substrate. The FP-TENG can generate up to 572 mW/m2 of power via contact–separation of the triboelectric electrified body at the top and bottom. With more folds of the FP-TENG, the triboelectric cross-sectional area increases, and, thus, the electrical output increases. In addition, the proposed TENG exhibits excellent durability without signal degradation under 5000 cycles of repeated pushing motions. To demonstrate its practicality, the FP-TENG was manufactured in the form of a wristwatch Velcro and connected to an electronic watch panel to supply power. Various deformations are possible with origami, and they can drive wristwatches through external forces. Therefore, the FP-TENG is expected to be utilized as a sustainable and promising eco-friendly energy source for small electronic devices. [ABSTRACT FROM AUTHOR]

The direct integration of paper-based microfluidic fuel cells (μFC's) toward creating autonomous lateral flow assays has attracted attention. Here, we show that an air-breathing paper-based μFC could be used as a power supply in pregnancy tests by oxidizing the human urine used for the diagnosis. We present an air-breathing paper-based μFC connected to a pregnancy test, and for the first time, as far as we know, it is powered by human urine without needing any external electrolyte. It uses TiO 2 -Ni as anode and Pt/C as cathode; the performance shows a maximum value of voltage and current and power densities of ∼0.96 V, 1.00 mA cm − 2 , and 0.23 mW cm − 2 , respectively. Furthermore, we present a simple design of a paper-based μFC's stack powered with urine that shows a maximum voltage and maximum current and power densities of ∼1.89 V, 2.77 mA cm − 2 and 1.38 mW cm − 2 , respectively, which powers the display of a pregnancy test allowing to see the analysis results. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) capable of efficiently harvesting various mechanical energies from the environment are an effective way to solve the energy supply problem of wearable electronic devices. A series of flexible and lightweight TENGs with different surface morphologies of "dots"–"lines"–"honeycombs" hierarchical micro-structures are developed using low-cost and easily accessible background paper as a substrate. Polydimethylsiloxane films with dots–lines–honeycombs hierarchical micro-structures are prepared by the spin coating to obtain larger contact areas and, thus, enhance the triboelectric effect. Under the same test conditions, the honeycombs TENG (H-TENG) with complex surface morphology has the largest output performance with an open-circuit voltage of 55 V and a short-circuit current of 2.7 μA, which is 2.1 and 2.5 times that of the flat TENG, respectively. By combining with nylon gloves, the H-TENG can harvest the mechanical energy during hand movement and realize sensing of hand movement patterns through the difference of electrical signals. In addition, this device can power the liquid crystal display screen through a rectifier circuit and capacitor. This simple and efficient TENG device shows great potential in the wearable field. [ABSTRACT FROM AUTHOR]

Rationale: Plasma‐based ionization sources play a vital role in rapidly analyzing diverse compounds without extensive sample pretreatment. In contrast to other sources, DC voltage‐based ionizations are more advantageous due to their high analytical sensitivity and good tandem with commercially available mass spectrometers without extra power supplies. However, their performance is at the risk of high current DC voltage and helium flow rate, which poses significant challenges to practical operation and increased expense. Methods: In this work, we propose a novel focusing plasma desorption ionization (FPDI) in which a visible plasma beam is favorably generated between a conducting wire in a polymeric tube and a counter electrode composed of metal mesh and filter paper drilled with holes. A systematic investigation has been conducted on the influences of the geometry of drilled holes in filter paper, applied DC voltage, helium flow rate, and filter paper size. The optimized system is used to analyze various pesticides in fluid foodstuffs. Results: Compared to metal mesh and conducting paper as the counter electrode for FPDI‐MS, combining metal mesh and filter paper drilled holes improved the analysis sensitivity by a factor of more than five. By applying the developed protocol for determining pesticides in complex matrixes such as orange juice and milk, a limit of detection as low as 1.3–3.0 ng mL−1 could be achieved. Conclusions: A novel FPDI‐MS technique has been developed by combining metal mesh and filter paper drilled with holes as the counter electrode and sample carrier. The corresponding improvement in analysis sensitivity facilitates the future expansion of FPDI‐MS applications into different pesticides and other compounds in complex matrixes. [ABSTRACT FROM AUTHOR]

Plant operators and policy makers frequently use energy benchmarking to assess the potential for reducing energy consumption from industrial plants. As benchmarking studies require considerable resources and the cooperation of plant operators it is tempting to try to merge or compare data from different studies. This paper reviews published benchmarks and energy-saving estimates from the paper and pulp industries to explore how comparable data from independent studies are. A literature review was conducted which identified that benchmarks were either produced through a top-down process using annual production and fuel consumption data or through a bottom-up process from process-level data. It was concluded that top-down benchmarks are useful in measuring national trends but are of little value to individual plants. For common process such as Kraft pulp production it is possible to compare values from different studies but only if sufficient information is given in the original studies to confirm that their scope is identical. However, it is unlikely that improvement rates in energy use can be inferred from the difference between studies that use different sources, as the degree of disagreement between contemporary studies is of the same order as the identified potential energy savings. Benchmarking studies were found to provide good summaries of potential technological improvements although there is some inconsistency in estimations of potential impacts. [ABSTRACT FROM AUTHOR]

As a mainstream power storage and supply device, batteries are continuously upgraded. The microfluidic fuel cell has great development potential, and the paper-based microfluidic fuel cell is the latest achievement of its lightweight, which can be applied in the field of medical and biological detection. In this work, the cell models with various folding forms and unconventional absorption pads are creatively constructed, then the influence mechanism on cell performance is revealed by numerical simulation. Both transient and steady-state simulation methods are employed to monitor the whole process of paper-based microfluidic fuel cell. Conclusions show that the cell performance decreases with the increase of folding angle, the peak power density is as low as 1.71 mW/cm2, and the corresponding fuel utilization is only 2.73%. The changes in the absorbent pad shapes have little improvement on cell performance, thus the most direct way is increasing the absorbent pad volume. Moreover, materials with better water absorption capacity can increase the maximum current density to 28.70 mA/cm2, and the appropriate increase of operating temperature can also increase the peak power density to 2.36 mW/cm2, but the effect on the cell is significantly weakened if the temperature exceeds a certain limit. [ABSTRACT FROM AUTHOR]

In this framework, experimental tests on different battery technologies, BMS and cooling systems are extremely important to extend the battery life and BEV performance (Sehil et al. [[13]]). Electrical machines and magnetic components, high-voltage voltage power converters, and battery storage systems are some basic bricks to build an effective and efficient energy conversion environment. Electrical Machines and Power Converters The electrical power conversion from renewable energy sources plays a crucial role in the development of a sustainable society. Finally, the fil rouge of every contribution in this section is oriented to investigate the power converters, electrical machines, magnetic components, and battery storage systems in actual energy conversion applications for renewable energy sources integration by a modelling approach. [Extracted from the article]

The Buck converter is a commonly used voltage regulator (VR) structure that supplies power to the load devices and responds to load transients. In most of the applications, the VR is controlled by voltage or current mode control, and some nonlinear approaches are used to improve the transient response which brings more complexities to the closed loop design. To achieve a fast transient response without over-regulation under a load step transient, this paper proposes a digital single-cycle regulation (SCCR) controller, which comprised a fast path, a slow path, and a neutralization path. Unlike the conventional PID control, the neutralization path of the SCCR controller is used to offset the excessive energy change in the first cycle after a load step occurs, which makes the inductor current reach its new static condition in a shorter period of time. The mathematical model of the SCCR control is established in this paper and a scanning algorithm is proposed for the design of the compensator parameters. Experimental results are presented to verify the improvement of the transient response when compared to the conventional and nonlinear PID control, the recovery time is decreased by 64.3% and 43% for load step-up and step-down when compared with nonlinear PID control. [ABSTRACT FROM AUTHOR]

Self-powered electronic equipment has rapidly developed in the fields of sensing, motion monitoring, and energy collection, posing a greater challenge to triboelectric materials. Triboelectric materials need to enhance their electrical conductivity and mechanical strength to address the increasing demand for stability and to mitigate unpredictable physical damage. In this study, polyaniline-modified cellulose was prepared by means of in situ polymerization and compounded with polydimethylsiloxane, resulting in a triboelectric material with enhanced strength and conductivity. The material was fabricated into a tubular triboelectric nanogenerator (TENG) (G-TENG), and an electrocatalytic pretreatment of mixed office waste paper (MOW) pulp was performed using papermaking white water as the flowing liquid to improve the deinking performance. The electrical output performance of G-TENG is highest at a flow rate of 400 mL/min, producing a voltage of 22.76 V and a current of 1.024 μA. Moreover, the deinking effect of MOW was enhanced after the electrical pretreatment. This study explores the potential application of G-TENG as a self-powered sensor power supply and emphasizes its prospect as an energy collection device. [ABSTRACT FROM AUTHOR]

Traction transformers are one of the most important equipment in the traction power supply system. Thermal aging of transformer insulation system determines its reliable life. To achieve an estimation of the insulation life of traction power transformers operated under real load condition, the effects of traction loads on the thermal aging of oil-paper insulation in traction transformers were investigated. First, the design principles for the accelerated thermal aging experiment were studied and proposed by considering magnitude (i.e., load rate) and frequency (i.e. spare time and lasting time) of the traction load. Then, an experimental system was established in the laboratory to conduct extensive accelerated thermal aging experiments, in which the traction loads were mimicked by using positive temperature coefficient (PTC) heating plates and a programmable logic controller (PLC). Finally, the experimental results were analyzed and discussed to reveal the effects of traction load on the thermal aging of oil-paper insulation in traction transformers. [ABSTRACT FROM AUTHOR]

This review analyzes papers presented at the "Second International Kosygin Readings: Energy- and Resource-Efficient Environmentally Safe Technologies and Equipment," an International Scientific and Technical Symposium Celebrating the 100th Anniversary of the Kosygin State University of Russia, which was held as part of the International Kosygin Forum. These papers consider the fundamental principles of methods for intensifying basic processes in various industrial technologies, the scientific fundamentals of the development of energy- and resource-efficient chemical and other processes, innovative developments in this field, issues of the environmental safety of technological processes and equipment, effective systems for increasing technosphere safety, the theory and calculation of heat and mass transfer processes in technosphere protection systems, the issues of digitization as an intellectual and technological factor for increasing the energy and resource efficiency of chemical-manufacturing processes and plants, and the results of studies aimed at developing the theoretical fundamentals of energy- and resource-efficient industrial machinery and equipment. [ABSTRACT FROM AUTHOR]

Paper-based microfluidics (lab on paper) emerges as an innovative platform for building small-scale devices for sensing, diagnosis, and energy storage/conversions due to the power-free fluidic transport capability of paper via capillary action. Herein, we report for the first time that paper-based microfluidic concept can be employed to fabricate high-performing aluminum–air batteries, which entails the use of a thin sheet of fibrous capillary paper sandwiched between an aluminum foil anode and a catalyst coated graphite foil cathode without using any costly air electrode or external pump device for fluid transport. The unique microfluidic configuration can help overcome the major drawbacks of conventional aluminum–air batteries including battery self-discharge, product-induced electrode passivation, and expensive and complex air electrodes which have long been considered as grand obstacles to aluminum–air batteries penetrating the market. The paper-based microfluidic aluminum–air batteries are not only miniaturized in size, easy to fabricate and cost-effective, but they are also capable of high electrochemical performance. With a specific capacity of 2750 A h kg−1 (@20 mA cm−2) and an energy density of 2900 W h kg−1, they are 8.3 and 12.6 times higher than those of the non-fluidic counterpart and significantly outperform many other miniaturized energy sources, respectively. The superior performance of microfluidic aluminum–air batteries originates from the remarkable efficiency of paper capillarity in transporting electrolyte along with O2 to electrodes. [ABSTRACT FROM AUTHOR]

The P&P (pulp and paper) industry in Taiwan is highly energy intensive and there is much product diversification. Taiwan has extremely limited coal and petroleum resources and imports 98% of its energy supply. Increased energy utilization efficiency to reduce energy consumption is necessary for industry in order to implement energy audit recommendations. This work summarizes the energy-saving potential of 118 firms from 2009 to 2013 as determined by on-site energy audits, as well as the energy savings implemented in 2011 by 72 firms in Taiwan's P&P industry, according to data from the on-line Energy Declaration System. It is found that the total of the energy-saving potential and the implemented energy savings are 168.3 and 762.1 TJ, respectively. The results of this study can serve as a reference for current P&P operations and as a base case for stimulating changes in energy utilization. [ABSTRACT FROM AUTHOR]

For high-power quasi-continuous laser drivers, the switched pulse power supply (PPS) is a promising technique due to its higher efficiency when compared with linear drivers. However, there are some digital control challenges with high precision, fast response and zero overshoot during the flat-top current stage. To promote the use of a switched PPS, this paper proposes a digital control strategy based on predictive current control under a multiphase PPS converter circuit. The key of the proposed control strategy is that predictive inner current control is only used for the master phase circuit. Meanwhile, the current sharing control is used for balancing the phase currents, and the setting outer current controller is used for keeping the whole converter control system stable and robust. Furthermore, to obtain fast and precise current tracking, a predictive average current control independent from the load values is derived. Moreover, a reducing gain method is applied to guarantee the stability of the inner current control. When compared with the conventional multiphase control, the proposed strategy possesses a faster dynamic response and a higher accuracy. In addition, it is more flexible under digital control implementation. A 360 W dual-interleaved PPS prototype is utilized for verifying the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

Rapid, low-cost, and sensitive nucleic acid detection and quantification assays enabled by microfluidic paper-based analytical devices (μPADs) hold great promise for point-of-care disease diagnostics and field-based molecular tests. Through the capillary action in μPAD, flexible manipulation of nucleic acid samples can be achieved without the need for external pumps or power supplies, making it possible to fabricate highly integrated sample-to-answer devices that streamline the nucleic acid extraction, separation, concentration, amplification, and detection. To detect minute amounts of genetic materials from clinical and biological samples, it is also critical to develop sensitive signal readouts that generate physically detectable signals for in-device nucleic acid detection and/or quantification. In this review, we will focus on μPAD approaches for the facile manipulation of nucleic acids and emerging signal transduction strategies allowing sensitive and specific nucleic acid detection in μPAD. [ABSTRACT FROM AUTHOR]

Use of recycled fiber material for the production of paper and paperboard has a significant share in solving problems related to environmental protection and conservation of energy resources. One of the most important processes for the paper recycling with printing press is a deinking. Perspective method for deinking of waste paper by the method of flotation is the enzyme treatment at neutral pH. The aim of this work is to study the deinking of recycled paper with offset printing press through flotation and use of enzymes. [ABSTRACT FROM AUTHOR]

This paper examines the potential of solar and hydrogen (H 2) energy-based hybrid energy systems for residential applications. The growing need for energy and the demand for sustainable energy sources have led to the development of integrated energy systems that combine renewable energy resources to meet energy needs. This paper overviews recent studies on hybrid energy systems for on-grid and off-grid residential utilizations. It discusses the system configuration and components of hybrid energy systems, including solar panels, electrolyzers, fuel cells (FC), and batteries. It also covers the technical optimization of integrated energy systems, including sizing, control strategies, and economic analysis. The key findings of this review paper indicate that hybrid energy systems can offer dependable and sustainable energy for residential applications. Through numerical analyses, the optimal dimensioning of the system elements and control strategies can significantly enhance the system's performance and lower the cost of energy. This study also highlights the challenges and opportunities for integrating hybrid energy systems within residential applications. Overall, it provides in-depth perspectives on the possibilities inherent in solar and hydrogen energy-based hybrid energy systems for residential applications. The findings can guide future research and the advancement of hybrid energy systems for sustainable energy solutions. • Comprehensive review on solar and hydrogen-based residential applications. • Holistic approach to system configuration, optimization, and economics. • Detailed analysis of interconnected components enhancing system efficiency. • Unique focus on real-world residential applications and scenarios. • Broad applicability across diverse geographical regions. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) technology can completely isolate the equipment from the power supply, and has been widely used. However, the transmission efficiency of WPT system is optimal only as the transmitting coil was completely aligned with the receiving coil. But in practical applications, the mobile devices are all dynamic system, and perfectly alignment of the coils is a very demanding condition. In order to solve this problem, the paper proposed a coil position adaptive adjustment control scheme of WPT system with lateral misalignment or angular misalignment. Firstly, the relationship between transmission efficiency and lateral misalignment and angular misalignment was analyzed. And the research results show that if there is a lateral misalignment between the coils, the transmission efficiency can be optimized by adjusting the angular misalignment. Secondly, based on the hill climbing algorithm, a coil position adaptive adjustment control method was proposed. Finally, a coil position adaptive adjustment WPT system experimental platform was built, and the experimental researches are carried on. The results of the experiment show that as the transfer distance is 0.10 m and the lateral misalignment is 0.12 m, the transfer efficiency can be increased from 38.38% to 55.61% through the proposed control scheme. And the results verify the feasibility and effectiveness of control scheme proposed in the paper. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Power converters enhance the DC-AC power supply by using multi-level inverters based on switched capacitor technology. The voltage stress on the switches in switched capacitor-based multi-level inverters decreases as the number of switches rises, and vice versa when the number of switches falls. This paper suggests a quadruple boost nine-level inverter based on a switched capacitor with a single voltage source to address this issue. Only nine switches are used in the suggested architecture to implement the inverter with two diodes and two capacitors. Since the diodes and capacitors are linked to the low voltage input side, the total voltage stress of the inverter is kept low even at the elevated for quadruple boost output voltage. The theoretical study, computations, and design parameters of the nine-level inverter are presented in this paper. The switching specifics of the seven-level boost extension topology are also reported in this work. Simulations and laboratory tests on a 120 W inverter prototype have confirmed the viability of the suggested topology. [ABSTRACT FROM AUTHOR]

A Virtual Power Plant (VPP) is a centralized energy system that manages, and coordinates distributed energy resources, integrating them into a unified entity. While the physical assets may be dispersed across various locations, the VPP integrates them into a virtual unified entity capable of responding to grid demands and market signals. This paper presents a tri-level hierarchical coordinated operational framework of VPP. Firstly, an Improved Pelican Optimization Algorithm (IPOA) is introduced to optimally schedule Distributed Energy Resources (DERs) within the VPP, resulting in a significant reduction in generation costs. Comparative analysis against conventional algorithms such as Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) demonstrates IPOA's superior performance, achieving an average reduction of 8.5% in generation costs across various case studies. The second stage focuses on securing the optimized generation data from rising cyber threats, employing the capabilities of machine learning, preferably, a convolutional autoencoder to learn the normal patterns of the optimized data to detect deviations from the optimized generation data to prevent suboptimal decisions. The model exhibits exceptional performance in detecting manipulated data, with a False Positive Rate (FPR) of 1.92% and a Detection Accuracy (DA) of 98.06%, outperforming traditional detection techniques. Lastly, the paper delves into the dynamic nature of the day ahead market that the VPP participates in. In responding to the grid by selling its optimized generated power via the day-ahead market, the VPP employs the Prophet model, another machine learning technique to forecast the spot market price for the day-ahead to mitigate the adverse effects of price volatility. By utilizing Prophet forecasts, the VPP achieves an average revenue increase of 15.3% compared to scenarios without price prediction, emphasizing the critical role of predictive analytics in optimizing economic gains. This tri-level coordinated approach adopted addresses key challenges in the energy sector, facilitating progress towards achieving universal access to clean and affordable energy. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid NBO–SDRN approach for a solar PV (SPV) array fed water pumping system utilizing a single-ended primary inductor converter (SEPIC) based BLDC motor drive. The proposed hybrid method combines Namib beetle optimization algorithm (NBO) and spiking deep residual networks (SDRN). Commonly, it is named the NBO–SDRN technique. The main goal of the NBO–SDRN method is enhanced energy efficiency, improved control algorithms, and optimal utilization of available solar energy resources. This paper focuses on integrating a SEPIC converter-based brushless DC motor drive in such systems to optimize energy conversion, enhance control, and promote environmentally friendly water supply. The BLDC (brushless direct current) motor drive and advanced control algorithms enable precise speed and torque control, improving overall energy efficiency and adaptability to varying water demand. By then, the NBO–SDRN method is done in the MATLAB working stage, and the execution is calculated with the present procedures. The proposed approach performs better outcomes in all existing singular spectrum analysis (SSA), heap-based optimization (HBO), and bee circle search algorithm (CSA) methods. From the result, the NBO–SDRN method-based efficiency is 95% higher than the existing methods. [ABSTRACT FROM AUTHOR]

The increasing integration of distributed energy resources such as photovoltaic (PV) systems into distribution networks introduces intermittent and variable power, leading to high voltage fluctuations. High PV integration can also result in increased terminal voltage of the network during periods of high PV generation and low load consumption. These problems can be solved by optimal utilization of the reactive power capability of a smart inverter. However, solving the optimization problem using a detailed mathematical model of the distribution network may be time-consuming. Due to this, the optimization process may not be fast enough to incorporate this rapid fluctuation when implemented in real-time optimization. To address these issues, this paper proposes a co-simulation-based optimization approach for optimal reactive power control in smart inverters. By utilizing co-simulation, the need for detailed mathematical modeling of the power flow equation of the distribution network in the optimization model is eliminated, thereby enabling faster optimization. This paper compares three optimization algorithms (improved harmony search, simplicial homology global optimization, and differential evolution) using models developed in OpenDSS and DigSilent PowerFactory. The results demonstrate the suitability of the proposed co-simulation-based optimization for obtaining optimal setpoints for reactive power control, minimizing total power loss in distribution networks with high PV integration. This research paper contributes to efficient and practical solutions for modeling optimal control problems in future distribution networks. [ABSTRACT FROM AUTHOR]

The consumption of high power and an extended start-up time are some of the major issues faced by piezoelectric energy harvesting. With this in mind, a control circuit with an extremely low power consumption of a few milliwatts is designed in this paper to energize heavy loads like wireless sensor nodes. A low-duty cycled self-powered control circuit, which works only at the maximum power point, is proposed in this paper. During a cold-start, optimum operative conditions can be achieved by this circuit. Moreover, a low power threshold at the input is sufficient to start the circuit. An additional piezoelectric transducer or a DC power supply is not required to operate this designed circuit. In terms of harvesting energy, performance enhanced by 320% can be achieved by this circuit when compared to the standard energy harvesting circuit when connected to a series-synchronized switch harvesting on an inductor (SSHI) with a large storage capacitor of 150 mF. An input power of 4.42 μW is enough for the circuit during cold-start and it consumes an ultra-low power of 0.3 μW. [ABSTRACT FROM AUTHOR]

This paper is concerned with a hydraulic cylinder directly controlled by a variable speed motor-driven fixed-displacement pump. The considered configuration is referred to as a one-motor-one-pump (1M1P) motor-controlled hydraulic cylinder (MCC). A 1M1P MCC with a hydraulically driven passive load-holding function enabled by controlled system pressures is proposed. The proposed load-holding functionality works if there is a standstill command, a loss of power supply, or a hose rupture. Additionally, this paper conducts a comprehensive analysis of the proposed system's operation and load-holding function across four quadrants. The simulation results demonstrate four-quadrant operation and good load-holding performance under the aforementioned scenarios. In conclusion, the proposed 1M1P MCC can be successfully used on practical applications characterized by overrunning loads and four quadrant operation. [ABSTRACT FROM AUTHOR]

The development of DC microgrids is reliant on multi-input converters, which offer several advantages, including enhanced DC power generation and consumption efficiency, simplified quality, and stability. This paper describes the development of a multiple input supply based modified SEPIC DC–DC Converter for efficient management of DC microgrid that is powered by two DC sources. Here Multi-Input SEPIC converter offers both versatility in handling output voltage ranges and efficiency in power flow, even under challenging operating conditions like lower duty cycle values. These features contribute to the converter's effectiveness in managing power within a DC microgrid. In this configuration, the DC sources can supply energy to the load together or separately, depending on how the power switches operate. The detailed working states with equivalent circuit diagrams and theoretical waveforms, under steady-state conditions, are shown along with the current direction equations. This paper also demonstrates the typical analysis of large-signal, small-signal, steady-state modeling techniques and detailed design equations. The proposed configuration is validated through the conceptual examination using theoretical and comprehensive MATLAB simulation results. Detailed performance analysis has been done for different cases with various duty ratios. Finally, to show the competitiveness, the multi-input SEPIC topology is compared with similar recent converters. [ABSTRACT FROM AUTHOR]

In this paper, the notion of a cohesive and self-sufficient grid is proposed. Based on a cohesive and self-sufficient virtual microgrid, an active distribution network is optimally planned, and an optimal configuration of demand-side resources, distributed generations, and energy storage systems are generated. To cope with stochastic uncertainty from forecast error in wind speed and load, flexibility reserves are needed. In this paper, the supply relation between flexibility and uncertainty is quantified and integrated in an innovative index which is defined as cohesion. The optimization objectives are a minimized operational cost and system net-ability cohesion as well as self-sufficiency, which is defined as the abilities both to supply local load and to deal with potential uncertainty. After testing the optimal configuration in the PG&E 69 bus system, it is found that with a more cohesive VM partition, the self-sufficiency of VMs is also increased. Also, a case study on uncertainty-caused system imbalance is carried out to show how flexibility resources are utilized in real-time operational balance. [ABSTRACT FROM AUTHOR]

In the built heritage studies, the intricate web of social and selective processes that define heritage is evident. These processes are, in many cases, intertwined with the notion of scale, examplified through the production of heritage sites at the local, national, and transnational scales. While heritage and geography scholars have articulated the role played by scale in heritage-making and argue against a rigid, fixed, and hierarchical understanding of scale, they highlight the constant reproduction of scale. There is, so far, limited explanation of how the perception of scale gets reproduced and how crucial actors manipulate scalar power and resources for heritage making and the reproduction of scale. To fill this gap, this paper delves into mainland China's heritage-making, using the southern Anhui historical villages as an example. Based on intensive 5-month field research, this paper has three findings: 1) The nomination process for a World Heritage Site is notably influenced by politics and selectivity; 2) Diverse stakeholders are pivotal in shaping heritage narratives; 3) Individual contributions to heritage creation directly interact with, and subsequently reshape, 'scale', an entity that is simultaneously discursive and tangible. By integrating the notion of 'scale' into heritage discussions, we illuminate two concurrent processes: creating hierarchies through rule assimilation by interpreting the UNESCO standard internally and evolving socio-spatial dynamics via the manifestation of individual agency with resource manipulation, scale jumping, and reproduction of scale. This approach aligns with the material orientation in human geography and repositions 'scale'. Here, it's not just an epistemological framework but also a tangible force that steers individual perceptions and actions and yields measurable material impacts. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a self‐powered SSHI piezoelectric energy extraction circuit combined with Modified FOCV‐MPPT technology, which analyzes the electrical characteristics of S‐SSHI operation. The paper demonstrates that the determination of the optimal operating state of S‐SSHI can be determined independently of the open‐circuit voltage. Based on the key parameters obtained from the theoretical analysis, the FOCV‐MPPT strategy is modified, and the corresponding functional circuit is designed. This strategy serves as an intermediate stage between S‐SSHI and the load, addressing the dependence of S‐SSHI output power on the load while avoiding the power supply interruption issue of the traditional FOCV‐MPPT strategy. In addition, the higher output power provided by S‐SSHI improves the utilization of MPPT technology. The correctness of the investigations is verified through the simulation and experiments. By using self‐powered S‐SSHI, the proposed circuit increases the output power of PEH by a factor of 2.46. In the open‐circuit voltage range of 2–7 V, the average maximum power tracking efficiency achieved 90.1%. The maximum tracking efficiency can reach 98%. [ABSTRACT FROM AUTHOR]

In recent years, with the continuous derivative of the Internet of Things (IoT) business, the use of various types of information sensing equipment needs to continue to increase. However, power supply conditions are getting tougher. On the other hand, as the function of the devices itself increases, the power consumption also increases, and the lack of energy demand is more obvious. To solve these problems, a dual-frequency RF energy harvesting system is designed in this paper. First of all, in order to expand the effective receiving range of RF energy, this paper designed a 920 MHz hexagonal windmill circular-polarized antenna, and added an energy receiving circuit in the 2.45 GHz band on this basis, which fully alleviated the problem of insufficient energy collection for small devices in the Internet of Things while ensuring a small volume wavelength ratio. In addition, in order to improve the energy conversion efficiency, this paper also designed a dual-frequency rectifier circuit based on conjugate separation matching, using the harmonic signal of 920 MHz signal to broaden the bandwidth of 2.45 GHz. The experimental results show that the peak conversion rates of 920 MHz and 2.45 GHz channels are 72.8%@0dBm and 38.7%@-2dBm, respectively. Overall testing in a Wireless Fidelity (Wi-Fi) room with a commercial Radio Frequency Identification (RFID) reader. The experimental results show that the system can steadily output 3.29 V–3.3 V voltage within 6 m charging distance, which is 20% higher than the output voltage of the single-channel receiving system, and the receiving angle is 36.84% larger. [ABSTRACT FROM AUTHOR]

The Magnetic Pulse Compression (MPC) system is a well-established method for generating high-peak-power, short-duration voltage pulses, commonly used in pulse power supplies (PPS). Traditionally designed for a fixed high repetition rate, this paper explores the techniques and outcomes of variable repetition rate operation in an MPC-based PPS used to excite a copper vapor laser (CVL). Specifically, the PPS, initially designed for 9 kHz operation, is tested at three different rates: 8 kHz, 9 kHz, and 10 kHz. A mathematical model is developed, and experimental modifications are presented in this paper. The study investigates the impact of repetition rate variations on CVL parameters, particularly phantom current (Phantom current: 47% at 8 kHz, 54% at 9 kHz, and 51% at 10 kHz). Phantom current reduces at 10 kHz due to improved impedance matching. At 8 kHz, the laser output is 24W, increases to 30W at 9 kHz and 43W at 10 kHz with a plane-plane resonator configuration. This trend extends to the master oscillator power amplifier (MOPA) at 10 kHz, resulting in a 50% increase in optical power output compared to 9 kHz. This improvement at 10 kHz applies to various parameters, including optical pulse characteristics, average power, electro-optic efficiency, energy per pulse, reduced jitter, and impedance matching. [ABSTRACT FROM AUTHOR]

Aiming to overcome the obstacles of power supply requirement and chip usefulness in practice, a low-cost and convenient portable electrochemical sensing device is introduced for the first time, featuring bipolar electrode system, LED read-out, laminated paper-based devices, and low-voltage button cells. The electric circuits of this practical device are constructed on laminating films with copper and conductive carbon tapes, and the reservoirs facilitating chemical reactions are made with chromatography paper. The device is sensitive to electrochemical responses, validated by the demonstrative hydrogen peroxide and enzyme-assisted glucose detection. The business-card-size chip achieves sensitive analyte detection by naked eyes as well as further image processing in both laboratory samples and human serum samples testing, featuring detection limit as low as 1.79 μM and a dynamic range from 10 μM to 10 mM. This new practical design of point-of-care sensing chip entails the properties of facile fabrication, simple usage, high robustness, low power consumption, and accurate sensing showing the attainability of fabricating a useful and portable analytical device. [ABSTRACT FROM AUTHOR]

Renewable energy resources can potentially solve global warming issues that arise from the large amounts of CO2 emissions from currently used energy resources. Microbial fuel cells (MFC) can produce electrical energy from the environment, making them attractive for energy harvesting. The structures and mechanisms of MFC have been studied for a few decades, and the performance of MFC has constantly been improved using new materials in the devices or by interacting microbial species on the anode chamber of MFC. However, the ecological phenomena, especially inter‐species interactions, within the microbial community in MFC are still largely unknown. Analysis and control of the microbial community have high potential to improve the MFC performance. In this idea paper, I have provided ways to analyze the species interactions in the microbial communities of MFC: (a) empirical dynamic modeling for detecting species interactions in MFC, and (b) network analysis to explore the core microbe species in the MFC. The interaction analyses of the microbial communities in MFC devices can potentially contribute to improving the performance of MFC. [ABSTRACT FROM AUTHOR]

In this paper, an array piezoelectric energy harvester (APEH) is designed for energy collection from water hydraulic system. The APEH is arranged in a spatial axial array, exhibiting excellent insulation and waterproof properties. The effects of connection modes and pressure pulsation parameters on the output performance of APEH are investigated through theoretical analysis, simulation and experiment. The results show that the output electric energy of each piezoelectric disk is consistent, and it is generated by the deformation caused by pressure pulsation. The connection modes show significant differences at different resistances. Series and parallel connections have the same maximum output power. The parallel connection has a smaller optimal resistance and has advantages in practical engineering applications. Both the pressure amplitude and the pulsation frequency affect the output voltage and power and increasing the pulsation frequency leads to the decrease of optimal resistance. By employing parallel connection, APEH can achieve higher output at lower load resistances. When the resistance is 12 kΩ, the average power and power density are reach as 997.63 μ W and 2.54 μ W mm−3, respectively. In summary, the APEH proposed in this paper offering a viable solution for energy recovery in water hydraulic systems and the sustainable power supply of the sensors, along with providing relevant theoretical references and practical schemes. [ABSTRACT FROM AUTHOR]

Flexible all-solid-state supercapacitors (FASSCs) have attracted much attention as power supplies for portable and wearable electronic products. Herein, we report the fabrication of a foldable, extra lightweight, flexible chopped carbon fiber paper (CFP) with a porous network structure prepared via wet-mold papermaking that can serve as a conductive substrate. The conductivity and pseudocapacitance of the electrode were improved by controlling the growth of 3D Cu(OH) 2 nanorod arrays on CFP substrate. The Cu(OH) 2 @CFP electrode has a high specific capacitance of 421.8 mF cm−2 at a current density of 0.5 mA cm−2 with capacitance retention of 82.98% at a current density of 10 mA cm−2 after 5000 charge-discharge cycles. The FASSC manifested not only a large capacitance of 196.1 mF cm−2 at 2 mA cm−2, as well as energy and power densities of 6.97 × 10−2 mWh cm−2 and 1.6 mW cm−2, respectively, but also excellent stability of 80.3% over 5000 cycles at 5 mA cm−2. In addition, we confirmed that the FASSC has a large bending angle and can be twisted into various shapes, thereby indicating its applicability in portable and wearable electronic devices. [Display omitted] • The folding, ultra-light carbon fiber paper was prepared by Papermaking wet molding. • 3D Cu(OH) 2 nanorod arrays were controlled to grow on CFP substrate. • Cu(OH) 2 @CFP electrode exhibits prominent flexibility and capacitive properties. • The commercial LED can be lit in series by two FASSC devices for up to 6 min. [ABSTRACT FROM AUTHOR]

In this work, a handheld paper-based bipolar electrode-electrochemiluminescence (P-BPE-ECL) system has been proposed. In this system, a rechargeable battery is used for power supply, while a smartphone is applied for read-out of ECL signal. For the P-BPE-ECL, the carbon ink-based BPE and driving electrodes are screen-printed on the paper, and the wax-screen-printing is employed to fabricate microfluidic channels on electrode-patterned paper. Moreover, the luminol/H 2 O 2 -based ECL reaction is applied to demonstrate the quantitative ability of the P-BPE-ECL system. Under optimized conditions, H 2 O 2 can be determined over the range of 5–5000 μM, with a detection limit of 1.75 μM, and relative standard deviations (RSDs) of 7.59%, 3.82% and 4.93% for 10, 100 and 1000 μM H 2 O 2 (n = 5). Thus, this system has an acceptable sensitivity, dynamic range, stability and reproducibility. Finally, the applicability of the P-BPE-ECL system is demonstrated for detection of glucose in phosphate buffer solution (PBS) and artificial urine (AU) samples, with the detection limits of 0.017 mM and 0.030 mM, respectively. Moreover, the P-BPE-ECL system has the ability to perform high-throughput detection of glucose. Therefore, the developed system can provide a new platform for many applications such as point-of-care testing, health diagnosis and environmental monitoring. [ABSTRACT FROM AUTHOR]