Electric Harvesting Research Articles

Electricity Harvesting Tiles

Electricity Harvesting Tiles

Numerical investigation of switchable cooling-heating-power trigeneration system based on flow channel control in summer

In this study, a numerical model is proposed via MATLAB software to respond to the dynamic indoor heating and cooling loads. This model combines spectral splitting PV/T systems and sky radiative cooling to achieve switchable heating, cooling, and electricity harvesting. Especially in the summer, the application of sky radiation cooling technology can lower the energy consumption of buildings. Meanwhile, the outdoor parameters and the operating factors are studied to explore the effects on the electric power and cooling power. Results indicate the threshold value of solar radiation for running daytime mode or nighttime mode is vital to output performance, and the optimal threshold value is recommended as 150W/m2 to regulate the switchable system. The flow velocity affects the convective heat transfer effects between the flowing water and the glass. As the flow velocity increases from 0.0005m/s and 0.0040m/s, the mean electric power improves from 41.3W to 54.1W and the cooling power improves from 62.6W to 96.4W respectively. Hence, it is suggested to employ a flow velocity of 0.0040 m/s to augment the system's capacity and adopt a channel thickness of 5mm, which can effectively reduce material costs without substantially compromising the power output.

Forecasting spare part extractions from returned systems in a closed-loop supply chain

In a closed-loop supply chain, the reuse of spare parts from returned systems is a recovery process referred to as spare parts harvesting. The unpredictability of the parts supply capacity from returned systems is a challenge in healthcare industry as product returns depend on several factors and regulatory and legal requirements must be respected. The focus of this paper is to provide a forecasting method of harvested parts supply capacity in healthcare industry that combines statistical methods with field information and business knowledge to provide an informed forecast. We propose a dynamic forecasting process that gets updated monthly employing TSB-Croston, 12-month moving average, ARIMA, ARIMA with seasonality, and a new business knowledge based model. A prediction method of the inventory state changes is introduced. The forecasters judgment is transformed into validation rules for an automatic forecast adjustment. This method is evaluated on more than 1400 time series with intermittent behaviour representing General Electric Healthcare spare parts harvesting history. We evaluate the performance of our method compared to each tested model using a modified MAPE, MAE, MSE, and RMSE. By means of the designed method, the forecast performance is improved compared to all tested models.

All-Wood-Based Ionic Power Generator with Dual Functions for Alkaline Wastewater Reuse and Energy Harvesting.

Water-induced electricity harvesting has gained much significance for energy sustainability. Bio-based hydrovoltaic materials increase the attractiveness of this strategy. Although promising, it faces a challenge due to its reliance on fresh water and its inherently low power output. Herein, the energy from alkalinity-gradient power generation demonstrated the feasibility of reuse of alkaline wastewater to develop an all-wood-based water-induced electric generator (WEG) based on ion concentration gradients. The intermittent water droplets bring about uneven distribution of electrolyte and endow delignified wood with the difference of ion concentration along aligned cellulose nanochannels, thus supplying electrical power. The practice of using alkali reservoirs, including industrial wastewater, further contributes to electricity generation. The cubic WEG with a side length of 2 cm can produce an ultrahigh open-circuit voltage of about 1.1 V and a short-circuit current of up to 320 μA. A power output of 6.75 μW cm-2 is correspondingly realized. Series-connected WEGs can be used as an energy source for commercial electronics and self-powered systems. Our design provides a double value proposition, allowing for sustainable energy generation and wastewater reuse.

Electricity generation from carbon dioxide adsorption by spatially nanoconfined ion separation

Selective ion transport underpins fundamental biological processes for efficient energy conversion and signal propagation. Mimicking these ‘ionics’ in synthetic nanofluidic channels has been increasingly promising for realizing self-sustained systems by harvesting clean energy from diverse environments, such as light, moisture, salinity gradient, etc. Here, we report a spatially nanoconfined ion separation strategy that enables harvesting electricity from CO2 adsorption. This breakthrough relies on the development of Nanosheet-Agarose Hydrogel (NAH) composite-based generators, wherein the oppositely charged ions are released in water-filled hydrogel channels upon adsorbing CO2. By tuning the ion size and ion-channel interactions, the released cations at the hundred-nanometer scale are spatially confined within the hydrogel network, while ångström-scale anions pass through unhindered. This leads to near-perfect anion/cation separation across the generator with a selectivity (D-/D+) of up to 1.8 × 106, allowing conversion into external electricity. With amplification by connecting multiple as-designed generators, the ion separation-induced electricity reaching 5 V is used to power electronic devices. This study introduces an effective spatial nanoconfinement strategy for widely demanded high-precision ion separation, encouraging a carbon-negative technique with simultaneous CO2 adsorption and energy generation.

Multifunctional Piezoelectric Yarns and Meshes for Efficient Fog Water Collection, Energy Harvesting, and Sensing

Given global water scarcity and the quest for sustainable energy, there's a pressing need for integrated approaches addressing water‐energy interdependence worldwide. A practical approach for this challenge involves the implementation of fog water collectors. Herein, a polyvinylidene fluoride (PVDF) multifunctional device capable of harvesting water and electricity from wind is developed and tested, collecting up to 365 mg cm−2 h−1 of fog water. Due to the piezoelectric nature of electrospun PVDF, these yarns and meshes not only serve as piezoelectric sensors, enabling the detection of incoming fog flow and determination of its speed and, bust also harvest electricity by charging a capacitor, making it a green and renewable power source. In this study, promising insights are offered into developing efficient fog water collection methods and utilizing piezoelectric fiber‐based yarns and meshes for multifunctional applications in sustainable water management, energy harvesting, and sensing in a single device.

Charge-defect tuned PVDF based ternary biocompatible composite as skin touch actuated single electrode triboelectric nanogenerator for wireless healthcare monitoring

Here, PVDF/ZnO/Ag (PVDF – poly(vinylidene fluoride)) based ternary biocompatible composites with the unique feature of improved conductivity have been developed which have enabled enhanced energy harvesting performance. A single-electrode triboelectric mechanism has been used here to use the films directly on the human body (as they are biocompatible). The optimized piezoelectric nanogenerator (PENG) device has shown a very high output with ∼28 V of open-circuit voltage (VOC), 1.2 μA of short-circuit current (ISC), and 17 μW/cm2 of power density. On the other hand, the optimized single electrode triboelectric nanogenerator (SETENG) device has been found to show ∼175 V of VOC, 21 μA of ISC, and 170 μW/cm2 of power density. The enhanced output performance has been correlated with improved polarity, enhanced charge-defects, and improved tribo-negativity of the composites caused by Ag addition. Due to this high output, both the PENGs and SETENGs have been used here for different real-life applications including pressure sensing, vibration sensing, touch sensing, and powering small electronics. The biocompatibility of the films and the unique design of SETENGs with wireless activity have enabled them to harvest electricity from body movement and sense body movement, which was very advantageous for healthcare monitoring and phonation monitoring purposes.

Asymmetric self-powered cellulose-based aerogel for moisture-electricity generation and humidity sensing

In view of the current problems of fossil consumption and environmental pollution, harvesting electricity from water to obtain renewable and clean energy has become a trend. Herein, an asymmetric self-powered cellulose-based aerogel generator (SMEG) was proposed by directional freeze-drying using quaternized cellulose nanofibril (Q-CNF), sodium carboxymethylcellulose (CMC) and single-walled carbon nanotube. When exposed to humid air, the prepared aerogel generated ionic ionization and directional flow, resulting in a potential difference. The single SMEG could separately produce a continuous voltage and current output of up to 668 mV and 6.4 μA, accompanied by a power density of 0.871 μW⋅cm−2 at high humidity (90 %). Meanwhile, connecting several SMEG devices could directly provide satisfied power for some commercial electronics including LED lights and calculators. More importantly, it was compatible for applications in contactless sensing and respiratory monitoring with high moisture sensitivity and good durability. This work provides a low-cost and environmentally friendly strategy for the optimal design of moisture-electricity generators and self-powered humidity sensors.

Nanofluid-Guided Janus Membrane for High-Efficiency Electricity Generation from Water Evaporation.

Harvesting electricity from widespread water evaporation provides an alternative route to cleaner power generation technology. However, current evaporation power generation (EPG) mainly depends on the dissociation process of certain functional groups (e.g., SO3 H) in water, which suffers from low power density and short-term output. Herein, the Janus membrane is prepared by combining nanofluid and water-grabbing material for EPG, where the nanoconfined ionic liquids (NCILs) serve as ion sources instead of the functional groups. Benefiting from the selective and fast transport of anions in NCILs, such EPG demonstrates excellent power performance with a voltage of 0.63V, a short-circuit current of 140µA, and a maximum power density of 16.55 µW cm-2 while operating for at least 180 h consistently. Molecular dynamics (MD) simulation and surface potential analysis reveal the molecular mechanism, that is, the diffusion of Cl- anions during evaporation is much faster than that of cations, generating the voltage and current across the membrane. Furthermore, the device performs well in varying environmental conditions, including different water temperatures and sources of evaporating water, showcasing its adaptability and integrability. Overall, the nanofluid-guided Janus membrane can efficiently transform low-grade thermal energy in evaporation into electricity, showing a competitive advantage over other sustainable applied approaches.

Bio-inspired polyionic membrane for long-lasting and repeatable electricity harvesting from moisture

Evaporation power generation (EPG), hailed as a promising clean power generation technology, has garnered significant attention. Nonetheless, achieving consistent and replicable performance of EPG remains a major challenge, hampering its practical application potential. Herein, we present the design of a tri-layered poly-ionic membrane (TL-PIM) inspired by transpiration processes in plants, that can not only continuously output electricity with an average voltage of ∼0.6 V for over 8 consecutive days with a maximum power density of 1.6 µW cm−2, but can also be reused for at least 70 cycles (> 350 h) with a stable voltage, demonstrating superior repeatability over most previous works. The excellent long-lasting and repeatable performance of EPG in the TL-PIM can be attributed to the stable nanochannels constructed by a hydrophilic polymer, 2D nanosheets, and poly-ionic liquids (PILs), where the bromide ions (Br-) in the PILs can shuttle back and forth selectively and efficiently during the power generation and discharge processes. More importantly, the TL-PIM can be integrated linearly to generate electricity within a wide range of temperatures and humidity, even outdoors, showcasing remarkable environmental adaptability. These findings on EPG indicate that the bio-inspired TL-PIM offers a promising venue for continuous and reproducible electricity generation by harnessing thermal energy from moisture, which holds significance for the sustainable utilization of EPG as a renewable energy source in the future.

Modified Wood Fibers Spontaneously Harvest Electricity from Moisture.

With the rapid development of modern society, our demand for energy is increasing. And the extensive use of fossil energy has triggered a series of problems such as an energy crisis and environmental pollution. A moisture-enabled electric generator (MEG) is a new type of energy conversion method, which can directly convert the ubiquitous moisture in the air into electrical energy equipment. It has attracted great interest for its renewable and environmentally friendly qualities. At present, most MEGs still have low power density, strong dependence on high humidity, and high cost. Herein, we report the development of a high-efficiency MEG based on a lignocellulosic fiber frame with high-power-density, all-weather, and low-cost characteristics using a simple strategy that optimizes the charge transport channel and ion concentration difference. The MEG devices we manufactured can generate the open-circuit voltage of 0.73 V and the short-circuit current of 360 μA, and the voltage can still reach 0.6 V at less than 30% humidity. It is possible to drive commercial electronic devices such as light-emitting diodes, electronic displays, and electronic calculators by simply connecting several electric generators in series. Biomass-based moisture-enabled electric generation has a low cost, is easy to integrate on a large scale, and is green and pollution-free, providing clean energy for low-humidity or high-electricity-cost areas.

Proton-Conductive COF Evenly Embedded Cellulose Aerogels toward Water Harvesting and Spontaneous Sustained Power Generation from Ambient Moisture and Human Respiration.

Herein, we develop a new intelligent moisture-sensitive hybrid aerogel by evenly embedding a proton-conductive covalent organic framework (COF-2SO3H) into a carboxylated cellulose nanofiber network (CNF-C) for water harvesting and spontaneous sustained electricity production from ambient humidity and human respiration. Our strategy first exploits the "suspending agent" role of CNF-C to stably disperse COF materials in water for forming uniform hierarchical hybrid structures. By utilizing the synergy of COF-2SO3H and CNF-C together with their inherent structure merits and surface group effects, the hybrid aerogel displays increased water uptake and ion conductivity. Upon asymmetric moisturization, it can create a self-maintained moisture gradient to engender a concentration difference for mobile Na+ and H+, resulting in efficient charge separation and diffusion. Thus, the hybrid aerogel-based coin-type generator achieves a continuous output voltage of ∼0.55 V for at least 5 h in ambient environments in contrast to that using pure CNF-C and carbon-based generators with transient voltage response. Intriguingly, the wearable generator with an aerogel in a mask is more sensitive to human respiration and achieves repeatable and reliable self-charge for persistent electricity along with an increased output voltage of up to 1.0 V and much faster self-charge (only 3 min), both of which surpass most reported moisture-enabled generators.

Power Generation from the Interaction of a Carbon Foam and Water.

Understanding the interaction mechanisms between the surface of carbon-based materials and water is of great significance for the development of water-based energy storage and energy conversion devices. Herein, a self-supporting electric generator is demonstrated based on water adsorption on the surface of the carbon foam (CF) that works with various water resources, including deionized (DI) water, tap water, wastewater, and seawater. It is revealed that the dissociation of oxygen-containing groups on the surface of CF after water molecule adsorption leads to a reduction of the surface potential of the CF. Through surface modulation techniques such as reduction and oxidation, a balance has been uncovered between the oxygen content and conductivity for the high-performance CFs. The generator can generate an open-circuit voltage of approximately 0.6 V in natural seawater with a power density of up to 0.77 mW g-1. A high voltage of more than 2 V can be achieved easily by assembling components connected in series to drive electronic devices, such as a light-emitting diode (LED). This work demonstrates a simple and low-cost method for electricity harvesting, offering an additional option for self-powered devices.

Moisture-induced ionovoltaic electricity generation using lead free 2-dimensional Cs3SbBiBr9 perovskite

Harvesting of electricity from the environment is an easy, effective and sustainable method for energy production: this is based on the ionovoltaic effect, a process where moisture absorption induces ionic motion in a material, thus driving the movement of charge carriers and generating electricity.

Photomechaelectric Nanogenerators with Different Photoisomers and Dipole Units for Harvesting UV Light Energy.

To date, transforming environmental energy into electricity through a non-mechanical way is challenging. Herein, a series of photomechaelectric (PME) polyurethanes containing azobenzene-based photoisomer units and ionic liquid-based dipole units are synthesized, and corresponding PME nanogenerators (PME-NGs) to harvest electricity are fabricated. The dependence of the output performance of PME-NGs on the structure of the polyurethane is evaluated. The results show that the UV light energy can directly transduce into alternating-current (AC) electricity by PME-NGs via a non-mechanical way. The optimal open-circuit voltage and short-circuit current of PME-NGs under UV illumination reach 17.4V and 696µA, respectively. After rectification, the AC electricity can be further transformed into direct-current (DC) electricity and stored in a capacitor to serve as a power system to actuate typical microelectronics. The output performance of PME-NGs is closely related to the hard segment content of the PME polyurethane and the radius of counter anions in the dipole units. Kelvin probe force microscopy is used to confirm the existence of the PME effect and the detailed mechanism about the generation of AC electricity in PME-NGs is proposed, referring to the back and forth drift of induced electrons on the two electrodes in contact with the PME polyurethanes.

Enhanced Solar Tracking System Using Internet of Things Technology

Solar energy has grown in popularity in recent years. Conventional solar panels cannot provide enough energy to meet consumer demand. Therefore, more solar panels are needed to meet consumer demand. The Internet of Things (IoT) Solar Tracker maximises solar energy collecting by connecting the physical and digital worlds. This study integrates IoT to improve solar tracker performance. Blynk uses the NodeMCU ESP8266 control unit to monitor voltage, current, and power usage. This research uses the Arduino IDE, a photoresistor sensor, and a current sensor, INA219. This work advances solar energy efficiency. By comparing solar panel electrical qualities in different environments, this research succeeded. To assess solar panel efficiency, 5 V and 12 V fans were used as loads. The results demonstrated that load configuration deliberately influences power and energy production. Solar panels produced greater power and energy under 12 V fan loads than 5 V loads. This observation assists solar energy system analysis and design. Second, the IoT solar tracker was tested for electricity harvesting. The solar tracker harvested more solar energy than a fixed orientation. After tracking the sun, it enhances voltage, current, power, and energy by 30%. Web dashboards and smartphone apps allow real-time IoT device monitoring and control. The interactive web dashboard displayed solar panel data. Track electrical properties and sunshine intensity. IoT devices influence solar tracker decisions and promote sustainable energy.Keywords: IoT solar tracker, Blynk application, NodeMCU ESP8266

Charge Exchange and Transfer between Water and van der Waals Monolayers Under Tensile Strains.

Charge exchange and transfer between water and low-dimensional materials are critical for water-related nanogenerators to harvest electricity from water. By first-principles calculations and molecular dynamics simulations, the interface interaction and charge transfer between ion-containing or pure water and two-dimensional (2D) van der Waals monolayers including transition metal dichalcogenides, hexagonal boron nitride, and graphene have been systematically investigated. Applying uniaxial tensile strain or the introduction of defects on 2D monolayers could significantly enhance the interface interaction and charge transfer from 2D monolayers to water molecules, as the tensile strain or defect weakens the bonds of 2D monolayers and changes the hydrogen bond networks in the interfacial water layer. In contrast, the presence of ions in water suppresses the charge transfer from 2D monolayers to water molecules and reduces interfacial adhesion because of the formation of hydrated ions and stronger charge exchange between ions and water molecules. These results reveal the role of strain, defect, and ion in dominating the charge exchange and transfer between water and 2D monolayers.

Plasma-Induced 2D Electron Transport at Hetero-Phase Titanium Oxide Interface.

Interfaces of metal oxide heterojunctions display a variety of intriguing physical properties that enable novel applications in spintronics, quantum information, neuromorphic computing, and high-temperature superconductivity. One such LaAlO3 /SrTiO3 (LAO/STO) heterojunction hosts a 2D electron liquid (2DEL) presenting remarkable 2D superconductivity and magnetism. However, these remarkable properties emerge only at very low temperatures, while the heterostructure fabrication is challenging even at the laboratory scale, thus impeding practical applications. Here, a novel plasma-enabled fabrication concept is presented to develop the TiO2 /Ti3 O4 hetero-phase bilayer with a 2DEL that exhibits features of a weakly localized Fermi liquid even at room temperature. The hetero-phase bilayer is fabricated by applying a rapid plasma-induced phase transition that transforms a specific portion of anatase TiO2 thin film into vacancy-prone Ti3 O4 in seconds. The underlying mechanism relies on the screening effect of the achieved high-density electron liquid that suppresses the electron-phonon interactions. The achieved "adiabatic" electron transport in the hetero-phase bilayer offers strong potential for low-loss electric or plasmonic circuits and hot electron harvesting and utilization. These findings open new horizons for fabricating diverse multifunctional metal oxide heterostructures as an innovative platform for emerging clean energy, integrated photonics, spintronics, and quantum information technologies.

Coupled iterative partitioning analysis for flow-driven piezoelectric energy harvesters

Scavenging of energy from the environment is an important engineering challenge. Recently, many researchers have investigated flow-driven piezoelectric energy harvesters, which harvest electricity from flow-induced vibration via the piezoelectric effect, and have applied them to drive low-power devices. Such harvesting is a complicated multi-physics problem involving fluid–structure interactions, piezoelectricity, and circuit design. The purpose of this study is to model such harvesting in detail and to solve the detailed model by strong coupling approaches. Although a few studies based on monolithic approaches have been recently reported, there is no study based on iterative partitioning approaches, which offer the advantage of allowing the use of existing sub-solvers. The novelty of the present study is to develop the iterative partitioning method-based analysis system. In this paper, we formulate nonlinear equations for flow-driven piezoelectric energy harvesting, of which unknown is structural displacement. We then provide an algorithm based on the iterative partitioning method. The proposed analysis system comprises an arbitrary Lagrangian–Eulerian-based fluid analysis solver, a monolithic structure–piezoelectricity interaction analysis solver, and a circuit analysis solver. Finally, we show the results of two numerical simulations to validate our proposed analysis systems. The first involves an analysis of piezoelectric energy harvesting in the absence of the effects of the surrounding fluid. The second considers flow-driven piezoelectric energy harvesting. The results of both simulations are in good agreement with those reported in previous studies.

Asymmetric GO-PPy based energy generator via synergistic flowing potential and ionovoltaic effect

Harvesting energy from ambient water, a renewable technology of generating electrical energy, promises to relieve the worldwide energy shortage. However, most of the electricity from ambient water is flowing potential, which has a short duration and is greatly affected by external conditions. Herein, a graphene oxide-polypyrrole-nonwoven fabric (GO-PPy-NWF) with asymmetric structure based water-induced energy generator is developed to harvest electricity via synergistic flowing potential and ionovoltaic effect. Electric power of ∼0.86 V and ∼40 μA can be harvested for ∼40 min with 0.1 mL brine or seawater infiltrating into the generator. Moreover, under one sun, the GO-PPy-NWF achieves electric power up to ∼0.93 V due to rapid evaporation. The GO-PPy-NWF harvests electricity by water to light up light emitting diodes (LEDs) and small electronic devices, showing good practicability prospects with flexibility, low cost and sustainability.