Energy Harvesting Approach Research Articles

An analysis of phase change material for subterranean cooling of the thermoelectric energy harvesting system at asphalt pavement

ABSTRACT This study proposes a novel thermoelectric harvester design for asphalt pavements, incorporating thermoelectric generators and phase change material. Through simulation and experimentation, a system was developed using PCM as a cold storage unit to maintain subterranean cooling. The design comprises an asphalt base holder and top and bottom plates for heat capture and dissipation, respectively. The exposed top plate harvests solar heat, while the submerged bottom plate connects to an H-shaped cooling element and a PCM container. This configuration leverages subterranean cooling and facilitates a significant temperature difference between the TEG plates. Consequently, the experiment observed a maximum attainable temperature difference of 42.22°C with PCM compared to 14.39°C without PCM, translating to a three-fold increase in charging efficiency, as demonstrated by a 5 V supercapacitor fully charged within 2.6 h. This novel TEG design offers a promising approach for self-sustainable energy harvesting from asphalt pavements.

Modeling of Photodynamic Self-Oscillation Based on a Suspended Liquid Crystal Elastomer Ball System.

Self-oscillation enables continuous motion by transforming constant external stimuli into mechanical work, eliminating the necessity for supplementary control systems. This holds considerable promise in domains like actuators, wearable devices and biomedicine. In the current study, a novel suspended liquid crystal elastomer (LCEs) ball system consisting of a light-responsive hollow LCE ball and an air blower is constructed. Stable illumination allows for its continuous periodic oscillation. Drawing from the theoretical model in conjunction with the dynamic LCE model, the control equations for the system are established, and its dynamic motion characteristics are explored from theoretical viewpoint. The numerical calculations suggest that two motion patterns are present, i.e., hovering and self-oscillatory patterns. The critical conditions required to initiate the transition between two motion patterns are quantified for different system parameters. As evidenced by the outcomes, manipulating the light intensity, damping coefficient, contraction coefficient, air density, gravitational acceleration, bottom illumination zone height, characteristic coefficient and vertical wind speed at the blower outlet facilitates precise control over the motion patterns as well as the amplitude and frequency. With its simple structure, customizable dimensions, remote activation and active manipulation, this system may potentially change the design approach for energy harvesting, microsensors and aerial vehicles.

Waste-to-energy: Repurposing flexible polyurethane waste for triboelectric nanogenerator applications

Triboelectric Nanogenerators (TENG) is a promising approach for clean energy harvesting. Light weight, flexible, cheap and environmentally-friendly materials are being explored as potential components in the TENG device in order to increase its efficiency. This paper reports the first effort to successfully utilize rebonded flexible polyurethane (RFPU) waste as a tribopositive material in a TENG device. A batch moulding technique was used to create two different densities (60 and 70 kg/m3) of flexible polyurethane (FPU) scraps, including customer waste and slabstock foam production waste. The current study investigates the effect of density on the compression strengths of the RFPU materials, as well as the impact on the output voltage of the TENG. Additionally, the effect of various RFPU sheet thicknesses (2, 4, 6, and 8 mm) as well as the effect of different applied forces and frequencies on the TENG's output voltage were investigated. The findings showed that the compressive strength increases with higher RFPU density. The output voltage values of the TENG device were recorded both with and without pre-charging. The results, without pre-charging, revealed that the highest output voltage of the TENG was obtained using an RFPU sheet with a density of 60 kg/m3. Furthermore, output voltage was shown to decrease with increasing RFPU sheet thickness and to increase with applied frequency. Pre-charging showed a similar trend, but yielded better results compared to the RFPU samples that were not pre-charged. The power density peaked at 0.085 mW/cm2, at a load resistance of 5 MΩ and a force of 4.7 N. The RFPU-based TENG successfully powered four white LEDs connected in series. Analysis of the embodied energy associated with using PU foam waste instead of virgin PU foam was conducted and demonstrated that utilizing PU foam waste provides environmental benefits due to the significant contribution of raw materials to the overall embodied energy in PU foam that is saved when reusing foam waste. Additionally, assessing the embodied energy of the components of the TENG device was also conducted and shows that the generated energy can partially offset the embodied energy of the TENG device. As a result, the prepared RFPU material not only helps to safeguard the environment but also shows great promise for use in developing more efficient and affordable TENGs in the future.

Enhancing MPPT efficiency in PV systems under partial shading: A hybrid POA&PO approach for rapid and accurate energy harvesting

Partial shading in operational environments introduces multiple peaks in the output characteristics of photovoltaic (PV) systems, presenting significant challenges to energy harvesting. This study introduces a novel meta-heuristic algorithm, termed POA&PO, which aims to address the maximum power point tracking (MPPT) issues in PV systems. The algorithm capitalizes on the global search capability of the POA method to quickly pinpoint the range with the maximum power, followed by the fast convergence of the PO method to ensure both rapidity and accuracy of the solution. Extensive simulation tests, conducted in MATLAB/SIMULINK, have demonstrated the efficacy of the POA&PO algorithm, achieving an average tracking efficiency of 99.97 % with a convergence time of 0.3 s in step response tests; under the EN50530 test standard, the algorithm also showed sustained and stable tracking of ramp signals. Moreover, practical testing utilizing a new, low-cost indoor PV simulator confirmed the algorithm’s high performance under controlled conditions, yielding an average tracking efficiency of 97.03 % and a convergence time of 0.18 s. This paper highlights the capacity of the developed algorithm to reliably, accurately, and swiftly achieve high energy transfer efficiency. Additionally, the innovative and economical experimental testing methods employed are emphasized, contributing to the practical applicability and cost-effectiveness of the proposed solution.

High‐Performance Piezoelectric Nanogenerator and Self‐Charging Photo Power Cell Using Hexagonal Boron Nitride Nanoflakes and PVDF Composite

Two‐dimensional (2D) piezoelectric hexagonal boron nitride nanoflakes (h‐BN NFs) exhibit substantial potential for energy harvesting, electronics, and optoelectronics applications. Herein, a free‐standing PVDF/h‐BN NFs (Ph‐BN) composite film is synthesized for multi‐functional purposes. First and foremost, a piezoelectric nanogenerator (PENG) device is fabricated using free‐standing Ph‐BN composite films and the energy harvesting properties are performed. The nanogenerator, Ph‐BN‐7.5 PENG, exhibits the highest output voltage of 50 V and current of 250 nA with a maximum power of about 2 μW compared to other fabricated composite devices. Further, a photo power cell (PPC) is fabricated using PVA‐EY mixture dye as the photosensitive part or solar energy absorber, and Ph‐BN 7.5 film is utilized as the energy storage part. The PPC is self‐charged up to ≈1 V within 80 s under light illumination. The self‐charging mechanism for PPC is explained in detail. The Ph‐BN composite films demonstrate an innovative energy harvesting and storage approach, which can fulfill the energy prerequisite in the imminent future.

On the role of sliding friction effect in nonlinear tri-hybrid vibration-based energy harvesting

This work aims to develop an experimental investigation into the effectiveness of the sliding-mode approach for hybrid vibration-based energy harvesting. A proposed sliding-mode triboelectric-electromagnetic-piezoelectric energy harvesting model involves a cantilever beam with a tip mass exposed to magnetic and frictional forces. The experimental findings indicate that the system can achieve its peak inter-well oscillation output within a low-frequency range of 4Hz–6Hz. Friction has a lesser impact on the open-circuit voltage output at an excitation acceleration of 1.5g compared with 1g. The distribution of tri-stability changes with the presence of friction. This model provides a deeper understanding of the influence of the dry friction coefficient (0.2–0.5) on the interactive behaviors of different generator units.

Enhanced energy harvesting from random excitations: A dynamic amplifier-augmented hybrid bistable piezoelectric energy harvester

In the energy harvesting field, it is critical to efficiently convert ambient vibrations into usable electrical energy, especially under conditions characterized by low amplitude and random excitations. This study introduces a novel hybrid bistable piezoelectric energy harvester (HBPEH) designed to optimize energy conversion in challenging environmental conditions. The HBPEH features a unique piezoelectric cantilever beam integrated with a dynamic amplifier at the fixed end, significantly enhancing both rotational and lateral displacements of the beam. This innovation lowers the threshold for snap-through events, crucial for maximizing energy transfer in bistable systems, and enables superior energy harvesting capabilities. Furthermore, the HBPEH demonstrates significantly higher power outputs when subjected to excitation intensities beyond critical levels, outperforming conventional energy harvesters. Extensive numerical and theoretical analyses confirm that the HBPEH offers a promising solution for applications hindered by suboptimal energy conversion rates. Its ability to operate effectively under diverse and unpredictable excitation conditions underscores the HBPEH's robustness and superiority in advanced energy harvesting scenarios. The design improvements introduced in this study highlight the potential of the HBPEH to transform energy harvesting approaches. By addressing the limitations of traditional harvesters, the HBPEH provides enhanced efficiency and reliability, making it suitable for a broader range of practical applications in variable environmental conditions.

A hybrid energy harvesting approach for transmission lines based on triboelectric nanogenerator and micro thermoelectric generator

To effectively detect faults in transmission lines, monitoring the operating status of these lines is imperative. However, providing power to monitoring devices for transmission line status presents a significant challenge. In this research, a hybrid energy harvesting approach based on micro thermoelectric generator (MTEG) and triboelectric nanogenerator (TENG) is proposed, and a theoretical model for MTEG-TENG hybrid energy harvesting is established. This study develops an integrated energy harvesting prototype, which incorporates oscillating-TENG (O-TENGs), MTEGs, and a power management control unit. This prototype not only harvests energy from the vibrations of transmission lines but also converts the lines thermal energy into electricity. The Experiment results show that the maximum open-circuit voltages of O-TENG and MTEG reach 80.3 V and 1.094 V, respectively. Compared to a single MTEG energy harvesting device, the prototype of the MTEG-TENG hybrid energy harvesting device demonstrates a 5.36% improvement in energy harvesting and battery charging performance. Consequently, this approach achieves self-powered monitoring with excellent stability and lower manufacturing costs. It provides an efficient and durable power approach for transmission line status monitoring devices.

Enhancing energy efficiency in power looms: utilizing regression machine learning for electrokinetic energy assessment

This study focuses on optimizing electro-kinetic energy utilization in textile weaving units, addressing power interruptions, reducing electrical costs, and harnessing latent kinetic energy during the weaving process. Power looms, vital to textile production, often incur inefficiencies and increased operational costs due to underutilized kinetic energy. To address these challenges, three innovative electrokinetic energy harvesting approaches are proposed: the Modified Series-Parallel Piezo Matrix, bi-directional linear generation, and uni-directional non-linear power extraction methods. The research further incorporates the Super Lift and Ultra Lift DC-DC power conversion techniques to enhance energy efficiency. The Modified Series-Parallel Piezo Array integrates Piezoelectric elements to capture and convert discarded kinetic energy efficiently. The bi-directional linear generation method captures mechanical energy from both forward and backward movements in weaving, minimizing energy wastage. The uni-directional non-linear power extraction method optimizes energy recovery by targeting specific weaving cycle phases. Machine learning algorithms, including Gaussian Process Regression, Linear Regression, Neural Network, and Support Vector Machine, enable precise energy estimation for meticulous modeling and optimization. Rigorous validation through MATLAB simulations aims to bolster energy efficiency, trim operational costs, and promote sustainable energy practices in the textile industry, contributing to a more environmentally friendly and sustainable future for the sector.

Influence of Mesh Design and Surface Treatments on Particle Transport and Fate in a Vibration-Enhanced Flooded Bed Dust Scrubber

Respirable coal mine dust (RCMD) is one of the biggest occupational health hazards for underground coal miners. Dusty mining environments can cause long-term health problems, including pneumoconiosis and progressive massive fibrosis. The Mine Safety and Health Administration (MSHA) has recently revised regulations promoting enhanced dust mitigation technologies, which have sparked renewed interest in the development of dust mitigation technologies. The flooded bed dust scrubber (FBS) is one of the most widely used technologies; however, it is limited by technical challenges, the most notable being the potential to clog. Recent studies have shown that applying vibration to filter mesh can improve the overall efficiency of the scrubber and that the system can be readily integrated to existing continuous mining equipment using an energy harvesting approach. In this follow-up study, the impact of mesh design and surface modification on system efficiency was examined using different vibrating liquid-coated stainless-steel mesh panels in a laboratory-scale FBS. Based on the two-way interaction data from a multi-factor experimental design, the results show that the performance of the system can be optimized by using hydrophilic 20- or 30-layer filters and by excitation frequencies between 67 and 134 Hz. This laboratory study suggests that a 20-layer mesh screen with hydrophilic surface applications and optimized vibration parameters can perform similar to that of a 30-layer static mesh, which is typically used in industrial units.

Rainbow energy harvesting using a high-order topological meta-device

We present an innovative rainbow piezoelectric energy harvesting approach that harnesses the untapped potential of the topological meta-device for robust and efficient vibration energy trapping and conversion, from its theoretical rudiments, through design of the device to experimental validation. The rigorously designed meta-device features a series of second-order phononic topological insulators to host topologically protected corner states of different eigenfrequencies. By tailoring and tuning various corner sites, multi-frequency vibrations along a specially engineered channel that supports the edge states spanning these frequencies can be trapped into different corner sites. The vibrational energy is thus converted into electrical energy efficiently using strategically placed piezoelectric harvesters. Experimental results reveal the capability of the device in trapping targeted vibration, in which vibrational energy can be trapped into different corner sites in terms of its frequency, leading to an interesting rainbow energy conversion. This new approach not only implements high-efficiency energy harvesting but also offers enhanced design flexibilities for diverse applications by spatially separating vibrational frequencies.

DNA‐rGO Aerogel Bioanodes with Microcompartmentalization for High‐Performance Bioelectrochemical Systems

AbstractBioelectrochemical systems (BES) have garnered significant attention for their applications in renewable energy, microbial fuel cells, biocatalysis, and bioelectronics. In BES, bioelectrodes are used to facilitate extracellular electron transfer among microbial biocatalysts. This study is focused on enhancing the efficiency of these processes through microcompartmentalization, a technique that strategically organizes and segregates microorganisms within the electrode, thereby bolstering BES output efficiency. The study introduces a deoxyribonucleic acid (DNA)‐based reduced graphene oxide (rGO) aerogel engineered as a bioanode to facilitate microorganism compartmentalization while providing an expanded biocompatible surface with continuous conductivity. The DNA‐rGO aerogel is synthesized through the self‐assembly of graphene oxide and DNA, with thermal reduction imparting lightweight structural stability and conductivity to the material. The DNA component serves as a hydrophilic framework, enabling precise regulation of compartment size and biofunctionalization of the rGO surface. To evaluate the performance of this aerogel bioanode, measurements of current generation are conducted using Shewanella oneidensis MR‐1 bacteria as a model biocatalyst. The bioanode exhibits a current density reaching up to 1.5 A·m⁻2, surpassing the capabilities of many existing bioanodes. With its abundant microcompartments, the DNA‐rGO demonstrates high current generation performance, representing a sustainable approach for energy harvesting without reliance on metals, polymers, or heterostructures.

Anti-moisture, anti-bacterial cellulosic triboelectric materials enabled by hydroxyl coordination effect

Owing to their low cost, customizability, and environmental stability, cellulosic triboelectric materials have emerged among polymer materials. However, the rich hydrogen bonding network inherent in cellulose limits its polarity and electron-donating ability, and charge dissipation caused by the hygroscopicity of the hydroxyl-rich groups limits its application as a triboelectric material. In this study, a more convenient, economical, and environmentally friendly "stent surgery" strategy was adopted. The wetting and swelling of fiber molecules allowed Cu (II) coordination with hydroxyl groups in nanocellulose. The coordination effect of cellulose hydroxyl groups weakens the intermolecular hydrogen bonding network, leading to an increase in the molecular dipole moment and the formation of new polar regions to regulate its space charge distribution, which significantly improved the electron-supplying capacity of the nanocellulose materials, and the maximum output power density increased by a factor of 2.78 (from 45 to 125 μW cm−2). Notably, the CNF-Cu (II) triboelectric material demonstrated excellent antimicrobial (>99%) and UV transmittance (<8%) as well as resistance to humidity interference, exhibiting only 5.9% voltage output loss at high humidity (90% RH). The design of this study provides new approaches for cellulose polarity modulation and energy harvesting adapted to harsh environments.

Synergistic Hybrid Marine Renewable Energy Harvest System

This paper proposes a novel hybrid marine renewable energy-harvesting system to increase energy production, reduce levelized costs of energy and promote renewable marine energy. Firstly, various marine renewable energy resources and state-of-art technologies for energy exploitation and storage were reviewed. The site selection criteria for each energy-harvesting approach were identified, and a scoring matrix for site selection was proposed to screen suitable locations for the hybrid system. The Triton Knoll wind farm was used to demonstrate the effectiveness of the scoring matrix. An integrated energy system was designed, and FE modeling was performed to assess the effects of additional energy devices on the structural stability of the main wind turbine structure. It has been proven that the additional energy structures have a negligible influence on foundation/structure deflection (&lt;1%) and increased system natural frequency by 6%; thus, they have a minimum influence on the original wind system but increased energy yield.

Energy harvesting approaches in IoT scenarios with very low ambient energy

The feasibility of multi-source energy harvesting in Internet of Things (IoT) scenarios with low and intermittent ambient energy is addressed. As a relevant case study, application to a smart cargo container system is analysed. The most relevant features of the main energy sources available in this target application are identified, and various transducers adapted to such sources are evaluated. Measurement results indicate that combined piezoelectric and thermoelectric generation inside cargo containers can significantly extend the battery lifetime of IoT end nodes embedded in such containers.

Effect of density and thickness of flexible polyurethane foam on the performance of triboelectric nanogenerators

Triboelectric nanogenerators (TENGs) based on flexible polyurethane foam (FPU) offer an attractive approach for energy harvesting for self-powered devices.

Energy harvesting and electricity production through dissolved carbon dioxide by connecting two form-stable phase change materials

Herein, we report a new solar energy harvesting approach by connecting two form-stable phase change materials in a moist environment with dissolved carbon dioxide (CO2).

Solution-mixed PANI-coated Bi2Si2Te6 nanosheet-based composite film for flexible thermoelectric energy harvesting

This paper introduces a novel approach for flexible thermoelectric energy (TE) harvesting via the synthesis and characterization of polyaniline (PANI)-coated Bi2Si2Te6 nanosheet (NS) composite films. The study focuses on enhancing the TE performance of the Bi2Si2Te6 NSs by coating their surfaces with PANI via a solution-mixing method. Specifically, the process involves exfoliation of Bi2Si2Te6 into nanosheets, followed by coating with camphorsulfonic acid (CSA)-doped PANI. An investigation of the TE power factor of the PANI-coated Bi2Si2Te6 NS is then conducted by analyzing the influence of the PANI coating times, and the results are explained in terms of the charge-carrier transport. Thus, the PANI-coated Bi2Si2Te6 NS composite films obtained using two coating cycles are shown to exhibit a maximum power factor of (∼411 μW/m·K2 at 500 K). Further, the flexibility and bending stability of the composites are revealed by an evaluation of their mechanical properties. Moreover, the as-fabricated PANI-coated Bi2Si2Te6 NS composite films exhibit outstanding durability after 1000 bending cycles. The findings contribute to the advancement of flexible inorganic/organic hybrid TE materials and their practical applications.

Hybrid nanogenerator for harvesting electric-field and vibration energy simultaneously via Maxwell’s displacement current

Hybrid energy harvesters (HEHs) have shown immense potential in powering distributed sensors. Conventional HEHs are assemblies of different energy harvesting modules, leading to complicated structures and intricate hybrid power management. This study presents a unique hybrid energy harvesting paradigm based on Maxwell’s displacement current for simultaneously harvesting electric-field and vibration energy. A triboelectric nanogenerator (TENG) is utilized to capture vibration energy via polarization of media (∂P⁄∂t), while the parasitic capacitance between TENG’s metal electrodes and AC electrical equipment generates electricity from time-varying electric field (ε0∂E⁄∂t). The continuous output of electric-field energy harvesting at high frequency (660 V, 105.7 mW/m2 × 50 Hz) and the pulse output of vibration energy harvesting at low-frequency (1.38 kV, 2.23 W/m2 × 1 Hz) exhibit comparable average charging power and complementary characteristics, contributing to a remarkable hybrid output performance. Furthermore, the similar energy conversion process and electrical properties of electric-field and vibration energy harvesting enable a universal hybrid power management system with simplified procedures and boosted efficiency (773 %). This work offers a cost-effective, efficient, and widely applicable approach for hybrid energy harvesting and paves the avenue for its practical applications.

Piezoelectric system on harnessing sound energy in closed environment

Traditional energy sources are progressively moving toward depletion, resulting in a growing scarcity of energy driven by demand. In contrast, the realm of acoustic energy harvesting remains relatively unexplored, particularly within enclosed environments. In this work, we proposed a novel piezoelectric energy harvesting system, enhanced with various circuit components such as operational amplifiers and voltage quadruplers. Piezoelectric transducers are a type of electro acoustic transducer that convert the electrical charges triggered by some forms of mechanical vibrations like sound into energy. The core of the system relies on the utilization of piezoelectric technology to transform untapped sound energy into electrical energy. This innovative energy harvesting approach holds the promise of enhancing the quality of sound conditioning within enclosed spaces. Furthermore, the proposed methodology serves to mitigate the risk of noise-induced trauma, which has the potential to cause detrimental long-term effects. It is also cascade into a transformative trajectory, offering sustainable energy harvesting avenues and fostering the amelioration of soundscapes within the tapestry of confined environs. The observations made increased the efficiency of the system by 6%, and the range is increased four times. In our experiments, we obtained a higher voltage of around 12 V for a theater setup with sound levels between 70 and 90 dB, which surpasses the existing results.