Sustainable Power Supply Research Articles

Predictive Control of a Wind Turbine Based on Neural Network-Based Wind Speed Estimation

Predictive control is an advanced control technique that performs well in various application domains. In this work, linearised control design models are first derived in state-space form from the full nonlinear model of the 5 MW Supergen (Sustainable Power Generation and Supply) exemplar wind turbine. Feedback model predictive controllers (FB-MPCs) and feedforward model predictive controllers (FF-MPCs) are subsequently designed based on these linearised models. A neural network (NN)-based wind speed estimation method is then employed to obtain the accurate wind estimation required for designing a FF-MPC. This method uses a LiDAR to be shared between multiple wind turbines in a cluster, i.e., one turbine is mounted with a LiDAR, and each of the remaining turbines from the cluster is provided with a NN-based estimator, which replaces the LiDAR, making the approach more economically viable. The resulting controllers are tested by application to the full nonlinear model (based on which the linearised models are derived). Moreover, the mismatch between the control design model and the simulation model (model–plant mismatch) allows the robustness of the controllers’ design to be tested. Simulations are carried out at varying wind speeds to evaluate the robustness of the controllers by applying them to a full nonlinear 5 MW Matlab/SIMULINK model of the same exemplar Supergen wind turbine. Improved torque/speed plane tracking is achieved with a FF-MPC compared to a FB-MPC. Simulation results further demonstrate that the control performance is enhanced in both the time and frequency domains without increasing the wind turbine’s control activity; that is, the controller’s gain crossover frequency (or bandwidth) remains within the acceptable range, which is about 1 rad/s.

Performance enhancement of the wavy cylinder-based piezoelectric wind energy harvester with different wave-shaped attachments

The vortex-induced vibration (VIV)-based piezoelectric wind energy harvester (PWEH) has a small working bandwidth and poor wind energy harvesting performance. In order to improve the output power of the PWEH and achieve sustainable power supply for microelectronic products, this study proposes a novel wavy cylinder-based PWEH with two wavy attachment rods attached to the surface of the wavy cylinder, the mathematical model of PWEH is developed. The flow-induced vibration (FIV) response mechanism and the energy harvesting characteristics of the wavy cylinder-based PWEH are numerically explored. The wavy cylinder with wavy-shaped attachments produces a three-dimensional shear layer that can increase the wavy cylinder’s aeroelastic instability range and realize the synergistic effects of VIV and galloping, which increases the wave cylinder’s vibrational amplitude and lowers the galloping critical wind speed. Compared with the typical VIV-PWEH, the novel wind energy harvester can work outside the VIV lock-in range, and its output power and voltage rise as wind speed does. The wavy attachment rods with triangular cross section have greater advantages than other rods, its output power is 6.13 mW at a wind speed of 5.7 m/s and load resistance of 100 KΩ, compared with the circular cylinder PWEH, the average power increases by approximately 166%. The study’s findings can theoretically promote the enhancement of PWEH’s energy harvesting efficiency.

Universal Energy Solution for Triboelectric Sensors Toward the 5G Era and Internet of Things.

The launching of 5G technology provides excellent opportunity for the prosperous development of Internet of Things (IoT) devices and intelligent wireless sensor nodes. However, deploying of tremendous wireless sensor nodes network presents a great challenge to sustainable power supply and self-powered active sensing. Triboelectric nanogenerator (TENG) has shown great capability for powering wireless sensors and work as self-powered sensors since its discovery in 2012. Nevertheless, its inherent property of large internal impedance and pulsed "high-voltage and low-current" output characteristic seriously limit its direct application as stable power supply. Herein, a generic triboelectric sensor module (TSM) is developed toward managing the high output of TENG into signals that can be directly utilized by commercial electronics. Finally, an IoT-based smart switching system is realized by integrating the TSM with a typical vertical contact-separation mode TENG and microcontroller, which is able to monitor the real-time appliance status and location information. Such design of a universal energy solution for triboelectric sensors is applicable for managing and normalizing the wide output range generated from various working modes of TENGs and suitable for facile integration with IoT platform, representing a significant step toward scaling up TENG applications in future smart sensing.

A sandwich-like flexible nanofiber device boosts moisture induced electricity generation for power supply and multiple sensing applications

Moisture-electricity generators (MEGs) are emerging as an attractive sustainable power supply due to their clean energy harvesting and conversion. However, there still remain some challenges in the development of high-performance and practical MEGs. Herein, we develop a novel sulfonate-polyaniline-bifunctionalized lignin (SAlignin), which can be incorporated into additive polyacrylonitrile for engineering electrospun nanofiber membrane (BioMem) to improve moisture power generation. To achieve maximal electric conversion efficiency, a flexible sandwich-like MEG (fMEG) consisting of an outer bilayer electrode of carbonized BioMem and an inner hygroscopic layer of as-spun BioMem is constructed. The unique structures and compositions endow fMEG with optimal ion diffusion, streaming tendency and surface potential for moisture electric generation. Importantly, phase-field simulation reveals that the interpenetrating network of SAlignin and polyacrylonitrile has good moisture absorption capacity and electricity generation, thereby boosting electric outputs. We identify that fMEG exhibits SAlignin-dose dependent increase in power conversion efficiency, and can generate a stable voltage of 0.28 V and current of 125 nA/cm2. In addition, electric output can be further improved by assembling multiple fMEG units in series or parallel, which is sufficient to power up electronic devices. More excitingly, fMEG can sensitively detect humid wind, and especially harvest the energy from human breath for respiration monitoring. Particularly, fMEG exhibits the potential of real-time monitoring of different human motions, including finger movements, sound waves and neck pulses. Therefore, our study provides new insights for advancing MEGs and related applications.

Multiphysics Co-Simulation and Experimental Study of Deep-Sea Hydrothermal Energy Generation System

With the continuous deepening of research on seafloor hydrothermal observations, the demand for a sustainable power supply of observation equipment is increasingly urgent. A kind of device that utilizes the temperature difference near hydrothermal vents to provide power is studied. However, the frequent experiments required for in-depth research on this device contradict the rare opportunities for hydrothermal field experiments and the difficulty in laboratory replication. In response to the above difficulties, a multiphysics co-simulation of the deep-sea hydrothermal energy generation system is studied in this paper. Firstly, the output performance analysis and modeling of the TEG installed in the device under pressure are carried out. An enhanced heat transfer model of the system is proposed for the hydrothermal fluids in the flow channel of the device. Then, the thermoelectric model of TEG and the heat transfer model of the device are jointly simulated by using Fluent and Simulink software. Eventually, the simulation data are compared with the data obtained through experiments. The average absolute of the relative error of the open-circuit voltage is 5.07%, and the maximum one is 6.28%. The corresponding values of the maximum output power are 5.16% and 6.79%, respectively. Therefore, the performance of the hydrothermal thermoelectric power generation system and the correctness of the proposed overall co-simulation model are verified.

Simple and Portable Self-Powered Sensor Using Ultrasonically Dispersed Graphene as an Electron Transfer Promoter for Ultra-Trace Atrazine Monitoring

Atrazine (ATZ) is a typical environmental endocrine disruptor that is persistent, highly residual, and widely present in various environmental media. Thus, it is of great significance to establish a sensitive and portable detection method for ATZ. In this work, a simple and portable enzymatic biofuel cell-based self-powered sensor (EBFC-SPS) for ATZ is proposed with the ultrasonically dispersed graphene (US-G) serving as the electron transfer promoter for both the enzymatic bioanode and molecularly imprinted cathode. US-G acts as a molecular bridge to stabilize the glucose dehydrogenase (GDH) immobilization and accelerate the electron transfer between GDH and anode, promoting the spontaneous electricity generation by the bioanode and sustainable power supply to the EBFC-SPS while ensuring cathode recognition and electron transfer. The portable detection of ultra-trace ATZ is achieved using a digital multimeter with a wide linear range of 0.5 pM to 100 nM, a low detection limit of 0.37 pM, excellent selectivity and stability in complex actual water samples based on the separation strategy of the bioanode power supply, and molecularly imprinted cathode target recognition. A promising platform for the design of portable sensing strategies with the EBFC-SPS has therefore been provided, which can also be extended to a wider range of environmental pollutants.

Integration of Footstep Power Generation with Energy Storage Systems for Sustainable Power Supply

Abstract: This design is generating electricity in a non traditional expressway in this type we exercise piezo sequel to induce electricity the pressure is applied on piezo component which creates the electricity that sequel exercised in step authority generation, in this we created a mechanical arrangement for them to turned on bedded system. The at mega 8/168/328 microcontroller is exercised control the tackle outfit detention on colorful outfit it can numerous tackle outfit through the series law and detention. the bedded system is interface with TV( liquid demitasse exposition) and the step count is reflected down in the TV the system main function and regulator is Arduino uno Ac and Dc regulator unidirectional regulator, 12v,1.3 Amp supereminent acid battery and an inverter is assumed 12 volts ac is converted to ac force the loads are actuated utilizing 230 volts Ac we're utilizing rechargeable battery to authority the compass and AURDINO is interface between the liquid demitasse flash 16X2 exposition. Though it will not meet the demand of electricity but as a matter of fact if we're suitable to design a authority generating bottom that can produce 100W on precisely 12 way, also for 120 way we can produce 1000 Watt and if we install similar type of 100 bottoms with this system also it can produce 1MegaWatt. Which itself is an acquirement to make it significant.

Kesterite based monograin photovoltaics: The ideal solution for sustainable power supply

Kesterite based monograin photovoltaics: The ideal solution for sustainable power supply

Human body heat-driven thermoelectric generators as a sustainable power supply for wearable electronic devices: Recent advances, challenges, and future perspectives

Thermoelectric generators are devices that directly convert heat flux or the temperature difference between two hot and cold surfaces into electricity. With the advancement of the Internet of Things (IoT) technology and the development of wearable and portable devices, the issue of providing a sustainable power source is one of the main challenges in the development path of these tools. Creating electric power by harvesting the waste heat from the human body is one of the effective solutions in this way. For this reason, the development and improvement of the technology of wearable thermoelectric generators have received much attention recently. Due to the low-temperature difference between the two sides of wearable thermoelectric generators and the high thermal resistance between the skin and the heated surface of these modules, the performance of these systems is highly dependent on their structural parameters and environmental factors. In this paper, it has tried to review all the previous studies regarding the impact of structural factors (such as the matching of internal and external thermal resistances, geometrical parameters of the module, design of heat source and sink, and flexibility of thermoelectric module) and environmental parameters (including the effect of ambient air temperature and humidity, skin temperature, and the interaction of power consumers with thermoelectric modules). Based on the studies, it seems that in optimizing the performance of wearable thermoelectric generators (WTEGs), it is necessary to consider the effect of the human body's thermoregulatory responses, such as skin temperature and sweating rate. The change in skin temperature directly affects the performance of WTEGs, and the change in sweating rate can also affect the thermal resistance between the skin and the hot plate and overshadow the matching of thermal resistances during operation.

Design and performance comparisons of power converters for battery energy storage systems

SummaryThe use of grid‐connected battery energy storage systems (BESSs) has increased around the world. In the scenario of high penetration level of renewable energy sources in distributed generation, BESS plays an important role to combine a sustainable power supply with a reliable dispatched energy source. Different power converter topologies are employed to connect the batteries to the grid, generally using single‐stage converters. However, the battery voltage changes according to its state of charge, which can introduce great variations in the dc‐link voltage. Therefore, the dc/ac stage converter must have its power switches designed to support this voltage variation. A controllable dc‐link voltage is achieved by inserting a dc/dc converter stage to connect the batteries to the dc/ac stage. Among the dc/dc converters, the interleaved bidirectional converter has been widely used due to the low input current ripple. However, the trade‐off of the insertion of the dc/dc stage is barely explored in the literature. Therefore, this work presents a methodology of analysis, considering the battery voltage variation and its influence on BESS power conversion system design and efficiency. Furthermore, it is proposed a power conversion system design oriented toward the voltage class of power switches and efficiency. The analysis in this study are conducted through the use of a case study approach, incorporating both simulated and experimental results.

Flexible, Wash-Resistant Human Mechanical Energy Harvesting and Storage System for Monitoring Human Movement.

The rapid development of personal portable electronic devices has brought an increasingly urgent need for flexible and portable power sources. Herein, a low-cost, wearable, efficient, sustainable energy harvesting and storage system for human motion detection has been developed, based on a supercapacitor (SC) and triboelectric nanogenerator (TENG). Carbon cloth (CC)-loaded ZnO/ZnS nanoarrays and a PVD-treated polyurethane conductive sponge are employed as positive and negative triboelectric friction layers, respectively. Besides, flexible and robust silicone rubber provides stable output performance and enables the TENG to harvest mechanical energy from human motion even under complex conditions. As a result, it shows excellent electrical output performance in terms of the open-circuit voltage, short-circuit current, and average power density, reaching 175 V, 12 μA, and 816.7 mW m-2, respectively. These outstanding performances enable the TENG to effectively charge an all-solid-state symmetrical SC (MnO2/LiMn2O4@CC//MnO2/LiMn2O4@CC) and subsequently store it as electrochemical energy for sustainable power supply. Because of the flexible all-texture-type structure of the entire system, it is capable of monitoring the human body's movement. This work has a promising future in random mechanical energy harvesting and storage, as well as human motion tracking.

Flexible photo-charging power sources for wearable electronics

Sustainable power supply is one of the key guarantees for wearable electronics. However, the trend of multifunctionality in integrated miniatured platform and higher operational expectation for modern untethered electronics raises great challenges. A flexible photo-charging system that harvests light energy from ambient environment and simultaneously charges the energy storage devices would be a promising power solution other than manual battery replacement or frequently recharging. In this review, we discuss the state-of-the-art flexible photo-charging technologies as power sources for wearable electronics. Planar photo-charging devices and wearable photo-charging fibers/textiles are summarized, including the materials engineering, device designs, and performances. Then we will briefly present their current applications in sensing and health monitoring. This review concludes with some key challenges and perspectives for further research and development.

Photovoltaics literature survey (no. 182)

Photovoltaics literature survey (no. 182)

Electret elastomer-based stretchable triboelectric nanogenerators with autonomously managed power supplies for self-charging systems

Stretchable power sources capable of accommodating large deformations are urgently demanded for various stretchable and wearable electronics. In this work, we report a stretchable electret-based triboelectric nanogenerator (SEB-TENG) consisting of elastomeric electret as electrification materials and organo-hydrogels as electrodes. The electret elastomer, prepared by uniformly dispersing SiO2 nanoparticles in the elastomer matrix and thermally injecting static charges, obtains a high surface potential, high tensile strain (796%), and long stability. Then, the SEB-TENG device also achieves high stretchability (423%) and high charge density (0.2 mC m−2). Furthermore, a power management module (PMM) is designed to maximize the energy utilization of the SEB-TENG. The integrated self-charging system can be sufficiently used to constantly power a watch, or charge a Li-ion coin cell which subsequently provides sustainable power supplies to a digital thermometer. This work provides a viable approach to simultaneously achieve high output performances and high stretchability of integrated power sources.

Effect of renewable energy development on sustainable development of small and medium enterprises potentials in Nigeria

The effect of renewable energy (RE) development on the sustainable development of SMEs' potential in Nigeria was empirically done to unlock the possibility of deciphering the perennial energy problem in Nigeria. The development of renewable energy (RE) resources and utilization can greatly benefit Small and Medium Enterprises (SMEs) in Nigeria by providing a reliable, sustainable and cost-effective power supply. This is especially important, as many sectors of Nigeria's economy, including SMEs, are highly dependent on the poor power supply that is currently available. Thus, this study specifically examines the effect of RE resources availability, generation, system efficiency and effectiveness, and utilization on SMEs’ sustainable development potential in Nigeria. A survey research design was adopted and a population of 73,081 SMEs across Nigeria was utilized with a sample of 398 SMEs selected using multi-stage sampling techniques. A validated questionnaire was administered to the owners/managers of the selected SMEs, information obtained from the questionnaire was collated, scrutinized, and analyzed using Structural Equation Model (SEM) with the aid of SMART PLS 4 software through the structural model. The findings revealed that RE resources availability, generation, system efficiency and effectiveness, and utilization potentials of SMEs have a positive and significant effect on the potential development of SMEs in Nigeria. The study concluded that RE resources availability, generation, system efficiency and effectiveness, and utilization have significant influence on SMEs’ sustainable development potential in Nigeria. Thus, government, private sectors, and international development partners should focus on providing more resources, knowledge, and support to enable SMEs to access, generate and effectively use renewable energy resources more efficiently.

Optimising a Biogas and Photovoltaic Hybrid System for Sustainable Power Supply in Rural Areas

This paper proposes a method for evaluating the optimal configuration of a hybrid system (biomass power plant and photovoltaic plant), which is connected to the electrical grid, to achieve minimum energy costs. The study is applied to a small rural municipality in the Valencian Community, Spain, as an energy community. The approach takes into account the daily energy demand variation and price curves for energy that are either imported or exported to the grid. The optimal configuration is determined by the highest internal rate of return (IRR) over a 12-year period while providing a 20% discount in electricity prices for the energy community. The approach is extrapolated to an annual period using the statistical data of sunny and cloudy days, considering 23.8% of the year as cloudy. The methodology provides a general procedure for hybridising both plants and the grid to meet the energy needs of a small rural population. In the analysed case, an optimal combination of 140 kW of rated power from the biogas generator was found, which is lower than the maximum demand of 366 kW and 80 kW installed power in the photovoltaic plant, resulting in an IRR of 6.13% over 12 years. Sensitivity studies for data variations are also provided.

Energy, economic and environmental (3E) evaluation of a hybrid wind/biodiesel generator/tidal energy system using different energy storage devices for sustainable power supply to an Indian archipelago

This paper thoroughly analyses energy, economic and environmental (3E) performance of using different battery (BAT) energy storage system like lead acid battery (LAB), lithium-ion battery (LIB), vanadium redox flow (VRF) battery and mechanical energy storage (MES) like flywheel and pumped hydro storage (PHS) using three different dispatch strategies (DS) such as cycle charging (CC), load following (LF) and generator order (GO), respectively. Andaman and Nicobar(A&N) Island of India have no main grid. Hybrid Optimization Model for Electric Renewable (HOMER) Pro software is used to study feasibility of power generation using various sources. Study incorporating tidal plant with wind turbine and Bio-DG in micro grid is considered first time for an Indian scenario as per authors’ knowledge with application of various DS and energy storage technologies. The superiority of LIB over LAB and MES is proved in this study. Wind/Bio-DG /tidal/LIB have relatively least net present cost(NPC), cost of energy (COE) of $1.30M and $0.263, respectively among five energy storage devices using CC dispatch strategy compared to other two strategies. It is investigated that LIB uses only 250 units of batteries, which is 46% less than total utilized LAB units for catering same load. In terms of expected lifespan, energy losses, energy production and state of charge (SOC), performance of LIB are superior to LAB. SWOT and sensitivity analysis have been performed considering fuel price and wind speed. Different techno economic indicators like cost summary, cash flow, fuel summary, economics, electrical parameters, renewable fraction (RF), return of investment (ROI), lowest simple payback period, internal rate of return (IRR), pollutant emission are considered and compared with each other for LAB and LIB combinations.

Resilience-Based Sequential Recovery Planning for Substations Subjected to Earthquakes

Electrical substations are crucial components in a power system while substation equipment can be easily damaged in an earthquake. Repairing the damaged equipment as soon as possible is essential to restore the functionality of the substation system and further secure the sustainable power supply of the power grid after the earthquake. However, the damaged equipment cannot be repaired simultaneously due to the limitation of emergency repair resources, and the recovery rate of the substation functionality will vary dramatically depending on the selection of different equipment repair sequences. Therefore, a sensible equipment repair sequence is needed to improve the recovery efficiency of the substation functionality. A resilience-based method was thus proposed in this paper to optimize the equipment repair sequence with the objective of minimizing the resilience index of the substation, which was defined as the post-earthquake overall functionality loss. The heuristic algorithm was incorporated into the systemic resilience assessment framework to find the optimal equipment repair sequence according to different initial damage states of equipment and the limitation of emergency repair resources. A case study was performed on a real-world substation system to illustrate and verify the proposed method, the analysis results can aid decision-makers in the post-earthquake recovery planning.

Dynamic measurement setups for validating piezoelectric energy harvesters in driving conditions

Sustainable power supply to flexible electronics is currently of high interest due to the transition to autonomous and self-driving vehicles. Piezoelectric Energy Harvesters (PEH) can be used as sustainable energy sources by harvesting the electrical power through the material deformation occurring in a tire. In this work, an analytical setup was developed to experimentally validate the energy harvesters for their use in tires. It was designed to measure the harvested electrical energy under simulated driving conditions. The setup includes a Dynamic Mechanical Analysis (DMA) as foundation to simulate the vibrations and dynamic responses occurring in a rolling tire. The dynamic properties and the output voltage from the harvesters were monitored under these sinusoidal conditions. For this, a PEH for tire applications was prepared in a sandwich configuration. It consists of a piezoelectric material, i.e. PolyVinyliDene diFluoride (PVDF) film, inserted in between two layers of electrodes, i.e. elastomers filled with conductive carbon black fillers. The electrical conductivity of elastomeric compounds was measured under dynamic conditions varying dynamic strain, frequencies, and temperatures. Dynamic strain and temperature resulted to be the most significant factors influencing the electrical conductivity of elastomers. Output power from the piezoelectric energy harvester was also measured at varied frequencies and temperatures. Both properties increase considerably the piezoelectric power. This development gives a promising method for analyzing the electro-mechanical properties of conductive and piezoelectric materials and optimizing their performance according to simulated tire-rolling conditions.

Modelling and Energy Management of an Off-Grid Distributed Energy System: A Typical Community Scenario in South Africa

Conventional power systems have been heavily dependent on fossil fuel to meet the increasing energy demand due to exponential population growth and diverse technological advancements. This paper presents an optimal energy model and power management of an off-grid distributed energy system (DES) capable of providing sustainable and economic power supply to electrical loads. The paper models and co-optimizes multi-energy generations as a central objective for reliable and economic power supply to electrical loads while simultaneously satisfying a set of system and operational parameters. In addition, mixed integer nonlinear programing (MINLP) optimization technique is exploited to maximize power system generation between interconnected energy sources and dynamic electrical load with highest reliability and minimum operational and emission costs. Due to frequent battery cycling operation in the DES, rainflow algorithm is applied to the optimization result to estimate the depth of discharge (DOD) and subsequently count the number of cycles. The validity and performance of the power management strategy is evaluated with an aggregate load demand scenario of sixty households as a benchmark in a MATLAB program. The simulation results indicate the capability and effectiveness of optimal DES model through an enhanced MINLP optimization program in terms of significant operational costs and emission reduction of the diesel generator (DG). Specifically, the deployment of DES minimizes the daily operational cost by 71.53%. The results further indicate a drastic reduction in CO2 emissions, with 22.76% reduction for the residential community load scenario in contrast to the exclusive DG system. This study provides a framework on the economic feasibility and effective planning of green energy systems (GESs) with efficient optimization techniques with capability for further development.