Power and Energy Commons^™

Magnetic Resonance In Metal-Ion Batteries: From Nmr (Nuclear Magnetic Resonance) To Epr (Electron Paramagnetic Resonance), Bing-Wen Hu, Chao Li, Fu-Shan Geng, Ming Shen

Journal of Electrochemistry

Metal-ion batteries have changed our quotidian lives. The research on the electrode materials for metal-ion battery is the key to improve the performance of the battery. Therefore, understanding the structure-performance relationship of the electrode materials can help to improve the energy density and power density of the materials. Magnetic resonance, including nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR), has been continuously improved during the past three decades, and has gradually become one of the important technologies to study the structure-performance relationship of electrode materials. This paper summarizes the progress of magnetic resonance research from our group on several …

Recent Advances In Electrochemical Kinetics Simulations And Their Applications In Pt-Based Fuel Cells, Ji-Li Li, Ye-Fei Li, Zhi-Pan Liu

Journal of Electrochemistry

Theoretical simulations of electrocatalysis are vital for understanding the mechanism of the electrochemical process at the atomic level. It can help to reveal the in-situ structures of electrode surfaces and establish the microscopic mechanism of electrocatalysis, thereby solving the problems such as electrode oxidation and corrosion. However, there are still many problems in the theoretical electrochemical simulations, including the solvation effects, the electric double layer, and the structural transformation of electrodes. Here we review recent advances of theoretical methods in electrochemical modeling, in particular, the double reference approach, the periodic continuum solvation model based on the modified Poisson-Boltzmann …

Recent Advances In Structural Regulation On Non-Precious Metal Catalysts For Oxygen Reduction Reaction In Alkaline Electrolytes, Xue Wang, Li Zhang, Chang-Peng Liu, Jun-Jie Ge, Jian-Bing Zhu, Wei Xing

Journal of Electrochemistry

Oxygen reduction reaction (ORR) in alkaline electrolytes is an important electrochemical process for metal-air batteries and anion exchange membrane fuel cells (AEMFCs). However, the sluggish kinetics spurs intensive research on searching robust electrocatalysts. Non-precious metal catalysts (NPMCs) that can circumvent the cost and scarcity issues associated with platinum (Pt)-based materials have been pursued and the challenges lie in the performance improvement to rival Pt-based benchmarks. As the composition and structure of the NPMCs have a significant impact on the catalytic performance, precise regulation on the catalyst structure holds great promise to bridge the activity gap between NPMCs and Pt-based benchmarks. …

Selective Co2 Reduction To Formate On Heterostructured Sn/Sno2 Nanoparticles Promoted By Carbon Layer Networks, Xue Teng, Yanli Niu, Shuaiqi Gong, Xuan Liu, Zuofeng Chen

Journal of Electrochemistry

Tin (Sn)-based materials have emerged as promising electrocatalysts for selective reduction of CO₂ to formate, but their overall performances are still limited by electrode structures which govern the accessibility to active sites, the electron transfer kinetics, and the catalytic stability. In this study, the heterostructured Sn/SnO₂ nanoparticles dispersed by N-doped carbon layer networks (Sn/SnO₂@NC) were synthesized by a melt-recrystallization method taking the low melting point of Sn (m.p. 232^oC). The N-doped carbon layer networks derived from polydopamine could attract more electrons on the electrocatalyst, serve as conductive agents and protect the ultrafine nanoparticles from …

Mass Loading Optimization For Ethylene Glycol Oxidation At Different Potential Regions, Sheng-Nan Sun, Zhi-Chuan Xu

Journal of Electrochemistry

Designing and fabricating the electrocatalysts is attracting more and more attention in recent years due to a global interest in developing techniques for electrochemical energy conversion and storage, as well as elelectro-synthesis of valuable chemicals. The activity is one of the key performance parameters for electrocatalysts, while the observed activity can be affected by mass loading of electrocatalysts. Here, we take cobalt oxide (Co₃O₄)/graphite paper electrode (Co₃O₄/GPE) as a model electrode to demon-strate how the mass loading of Co₃O₄ catalyst influences ethylene glycol (EG) oxidation in alkaline (KOH) by …

Economic Analysis Of Islanded Microgrid: A Case Study Of Kisiju Village - Coastal Region, Jackson Justo

Tanzania Journal of Engineering and Technology (TJET)

The concept of Microgrid (MG) has gained significant attention of researchers and projects on the business side of electrical power generation and utilization, particularly in electrification of islanded areas such as villages. Most of these microgrids are powered by renewable energy resources (RERs) and they distribute power in low voltage distribution networks. Hence, these systems are faced with reliability problems due to the intermittency nature of RERs which affect the technical as well as the return on Investment of specific projects. In the latter context, reliability and economic analysis of the MG systems is an inevitable choice. This paper presents …

Building Marginal Pattern Library With Unbiased Training Dataset For Enhancing Model-Free Load-Ed Mapping, Qiwei Zhang, Fangxing Li, Wei Feng, Xiaofei Wang, Linquan Bai, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

Input-output mapping for a given power system problem, such as loads versus economic dispatch (ED) results, has been demonstrated to be learnable through artificial intelligence (AI) techniques, including neural networks. However, the process of identifying and constructing a comprehensive dataset for the training of such input-output mapping remains a challenge to be solved. Conventionally, load samples are generated by a pre-defined distribution, and then ED is solved based on those load samples to form training datasets, but this paper demonstrates that such dataset generation is biased regarding load-ED mapping. The marginal unit and line congestion (i.e., marginal pattern) exhibit a …

Facile One-Step Hydrothermal Method For Nico2s4/Rgo Nanocomposite Synthesis For Efficient Hybrid Supercapacitor Electrodes, Ahmed Mysara, Sayed Y. Attia, Fouad I. El-Hosiny, M A. Sadek, Saad G. Mohamed, M M. Rashad

Nanotechnology Research Centre

Spinel nickel-cobalt sulfide (NiCo2S4) supported on reduced graphene oxide (rGO) was fabricated through a facile one-step hydrothermal method for energy storage applications. The distribution of the NiCo2S4 nanoparticles on the rGO surface was found to improve the supercapacitive performance of the assembled device. The NiCo2S4/rGO nanocomposite exhibits outstanding electrochemical behavior with a capacity (C)/specific capacitance (Cs) of 536 C g−1/1072 F g−1 at a current density of 1 A g−1. To further investigate the electrochemical behavior of the NiCo2S4/rGO nanocomposite, a hybrid supercapacitor (HSC) was constructed utilizing a NiCo2S4/rGO positive electrode and an activated carbon …

Joint Bidding Decision Of Wind Farms And Energy Storage Based On Newsvendor Model, Xinyue Sun, Jian Liu, Meng Ou, Yanyan Liu

Electrical and Computer Engineering Faculty Research & Creative Works

Currently, renewable energy generation has received more and more attention. This article focuses on wind energy generation, one of the renewable energy sources. Aiming at the intermittent and unpredictable wind power problems, according to the day ahead bidding mechanism in the power market, this paper introduces the energy storage system to maximize wind power merchants profit based on the newsvendor model. First, this paper focuses on the wind farms combined with storage system to put forward the optimal bidding decision of selling or buying electricity to the market one day in advance and the optimal bidding amount. Then, we analyze …

A High-Performance Continuous-Flow Mea Reactor For Electroreduction Co2 To Formate, Pei-Xuan Liu, Lu-Wei Peng, Rui-Nan He, Lu-Lu Li, Jin-Li Qiao

Journal of Electrochemistry

The electrochemical carbon dioxide reduction reaction (CO₂RR) is a promising approach to produce liquid fuels and industrial chemicals by utilizing intermittent renewable electricity for mitigating environmental problems. However, the traditional H-type reactor seriously limits the electrochemical performance of CO₂RR due to the low CO₂ solubility in electrolyte, and high ohmic resistance caused by the large distance between two electrodes, which is unbeneficial for industrial application. Herein, we demonstrated a high-performance continuous flow membranes electrode assembly (MEA) reactor based on a self-growing Cu/Sn bimetallic electrocatalyst in 0.5 mol·L^-1 KHCO₃ for converting CO₂ to …

Oxidative Efficiency Of Ozonation Coupled With Electrolysis For Treatment Of Acid Wastewater, Ze-You Hu, Feng-Yun Xiang, Ji-Qiang Mao, Ya-Lei Ding, Shao-Ping Tong

Journal of Electrochemistry

Establishment of an ozone-based advanced oxidation process (AOPs-O₃) for effective treatment of acid wastewater is an important and difficult task. The process of ozonation coupled with electrolysis (electrolysis-ozonation, E-O₃) has been reported to effectively degrade pollutants in neutral solution. We studied the efficiency of E-O₃ for degradation of acetic acid (HAc, an ozone inert chemical) in acid solution and found that E-O₃ had high oxidative efficiency at pH less than 3. For example, 52.2% of 100 mg·L^-1 HAc could be removed by E-O₃ in 120 min at pH 1.0, but only 2.2% …

Progress Of Pt-Based Catalysts In Proton-Exchange Membrane Fuel Cells: A Review, Long Huang, Hai-Chao Xu, Bi Jing, Qiu-Xia Li, Wei Yi, Shi-Gang Sun

Journal of Electrochemistry

Fuel cells are energy conversion devices that convert chemical energy directly into electricity. It has the advantages of high energy density, high utilization efficiency of fuel, clean and noiseless during working. Among all kinds of fuel cells, proton exchange membrane fuel cells (PEMFCs) are most popular since PEMFCs function at near ambient temperature, while their power densities are higher than those of other fuel cells. Currently, Pt-based nanomaterials are still the unreplaceable catalysts in commercialized PEMFCs. The lack of low-cost and high-performance cathode catalysts is still one of key factors that hampers the commercialization of PEMFCs. In this review, the …

Advances Of Phosphide Promoter Assisted Pt Based Catalyst For Electrooxidation Of Methanol, Meng Li, Li-Gang Feng

Journal of Electrochemistry

Transition metal phosphide (TMP), as an ideal catalytic promoter in methanol fuel oxidation, has received increased attention because of its multifunctional active sites, tunable structure and composition, as well as unique physical and chemical properties and efficient multi-composition synergistic effect. Some advances have been made for this catalyst system recently. In the current review, the research progresses of transition metal phosphides (TMPs) in the assisted electrooxidation of methanol including the catalysts fabrication and their performance evaluation for methanol oxidation are reviewed. The promotion effect of TMPs has been firstly presented and the catalyst systems based on the different metal centers …

Acetate Solutions With 3.9 V Electrochemical Stability Window As An Electrolyte For Low-Cost And High-Performance Aqueous Sodium-Ion Batteries, Dao-Yun Lan, Xiao-Feng Qu, Yu-Ting Tang, Li-Ying Liu, Jun Liu

Journal of Electrochemistry

Low-cost and high-safety aqueous sodium-ion batteries have received widespread attention in the field of large-scale energy storage, but the narrow electrochemical stability window (1.23 V) of water limits the energy density of aqueous sodium-ion batteries. The “water-in-salt” strategy which uses the interaction between cations and water molecules in the solution can inhibit water decomposition and broaden the electrochemical stability window of water. In this work, two types of low-cost salts, namely, ammonium acetate (NH₄CH₃COOH) and sodium acetate (NaCH₃COOH), were used to configure a mixed aqueous electrolyte for aqueous sodium-ion batteries. The solution consisted of …

Synthesis Of Lithium-Rich Manganese-Based Layered Cathode Materials And Study On Its Structural Evolution Of First Cycle Overcharge, Chen-Xu Luo, Chen-Guang Shi, Zhi-Yuan Yu, Ling Huang, Shi-Gang Sun

Journal of Electrochemistry

Lithium-rich manganese-based cathode materials have become one of promising cathode materials due to their low cost and large discharge specific capacity exceeding 250 mAh·g^-1. However, their problems such as low coulombic efficiency of first cycle and apparent voltage decay influence commercialization process. The high charging voltage will cause instability of structure and increase the hidden danger of the battery. Therefore, structural evolution of first cycle at higher voltage needs to be further studied. In this work, the precursor was synthesized by the co-precipitation method, and the lithium-rich manganese-based layered cathode materials were prepared by lithium-mixed and high-temperature sintering, …

Recent Advances Of Wind-Solar Hybrid Renewable Energy Systems For Power Generation: A Review, Pranoy Roy, Jiangbiao He, Tiefu Zhao, Yash Veer Singh

Electrical and Computer Engineering Faculty Publications

A hybrid renewable energy source (HRES) consists of two or more renewable energy sources, such as wind turbines and photovoltaic systems, utilized together to provide increased system efficiency and improved stability in energy supply to a certain degree. The objective of this study is to present a comprehensive review of wind-solar HRES from the perspectives of power architectures, mathematical modeling, power electronic converter topologies, and design optimization algorithms. Since the uncertainty of HRES can be reduced further by including an energy storage system, this paper presents several hybrid energy storage system coupling technologies, highlighting their major advantages and disadvantages. Various …

Evaluation Of The Accuracy Of Different Pv Estimation Models And The Effect Of Dust Cleaning: Case Study A 103 Mw Pv Plant In Jordan, Loiy Al-Ghussain, Moath Abu Subaih, Andres Annuk

Mechanical Engineering Graduate Research

The estimation of PV production has been widely investigated previously, where many empirical models have been proposed to account for wind and soiling effects for specific locations. However, the performance of these models varies among the investigated sites. Hence, it is vital to assess and evaluate the performance of these models and benchmark them against the common PV estimation model that accounts only for the ambient temperature. Therefore, this study aims to evaluate the accuracy and performance of four empirical wind models considering the soiling effect, and compare them to the standard model for a 103 MW PV plant in …

Development Of A Testing Station For Grid-Interactive Smart Inverter Systems, Yudong Lan

Dissertations and Theses

As renewable energy penetration increases within the electrical power grid, flexible power is required to ensure reliability. Reliability can be jeopardized by the fluctuation and non-dispatch ability of renewable generators. This instability is caused by an imbalance between the amount of power produced and the amount of power consumed. Grid-enabled battery inverter systems are considered a solution to offset voltage and frequency fluctuations, which arise due to this power imbalance.

The objective of this work is to develop a system for testing grid-enabled inverters. These inverters use one or more communication standards to control their interactions with the grid. This …

Data-Enabled Distribution Grid Management, Zohreh Sadat Hosseini

Electronic Theses and Dissertations

In 2020, U.S. electric utilities installed more than 94 million advanced meters, which brought the percentage of residential customers equipped with smart meters to 75%. This significant investment allows collecting extensive customer data at the distribution level, however, the data are not currently leveraged effectively to help with system operations. This dissertation aims to use the smart meters’ data to improve the grid’s reliability, stability, and controllability by solving two of the most challenging problems at the distribution level, namely distribution network phase identification and outage identification.

Distribution networks have typically been the least observable and most dynamic and locally …

The Development Of An Inexpensive Alternative To Industry Solar Simulators, Raines A. Vanhuss

OUR Journal: ODU Undergraduate Research Journal

Solar cells are a prominent renewable energy source used in the twenty-first century. In order for the technology to grow, research lab equipment is needed to measure and characterizes these cells. This report covers solar simulator devices and proposes an alternative design solution to lessen the cost of solar cell lab equipment. Common household light sources were tested by generating I-V characteristics using an amorphous silicon solar cell. The light bulb that generated the best I-V curve was selected and then tested for the optimal distance between the light source and the solar panel. The alternative solar simulator was then …

Reconfigurable Load-Modulated Power Amplifier For Energy- And Spectrum-Efficient Wireless Communications, Haifeng Lyu

Electronic Theses and Dissertations, 2020-2023

With the increasing demand for faster date rates and extensive user connectivities, the complex modulation schemes and large-scaled arrays have been widely researched and employed in the modern wireless links e.g., 5G and beyond-5G systems. These pose major challenges to design the power amplifiers (PAs) to accommodate the system level evolution. As the critical part, the power amplifiers (PAs) dominate the output power, efficiency, linearity and reliability of the radio frequency (RF) transmitter. Consequently, the PA's capability of maintaining an efficient, linear and reliable signal amplification operation is essential to the communication systems. On the other hand, due to the …

Power Inductors: Design, Modeling And Analysis, Subash Pokharel

Electronic Theses and Dissertations, 2020-2023

Power inductors, or reactors as they are called in the power industry, are one of the fundamental components of a power system. They serve various purposes in both conventional and emerging power systems including: power flow control, fault current limitation, reactive power compensation, harmonic filtering, and others. This dissertation explores the design and applications of conventional power inductors and ways to overcome their shortcomings and expand their functionalities. In addition, novel inductor designs are proposed and analyzed to address power system challenges. A series of inductors, including traditional constant reactance inductor, gapless ferromagnetic core reactor (GFCR) (both costant and variable …

Grid-Interactive Buildings: Modeling, Operations, And Security, Guanyu Tian

Electronic Theses and Dissertations, 2020-2023

Smart grids and smart buildings are two highly interdependent energy infrastructure systems. Buildings rely on the grid to provide reliable power while their flexibility can also be utilized to enhance the reliability and efficiency of power system operations. The quantification of heating, ventilation, and air condition (HVAC) system flexibility is critical to the operations of both the grid and buildings in demand response (DR) programs. However, the flexibility quantification is challenging due to the non-linearity and non-convexity of thermal dynamics associated with HVAC components. This dissertation proposes a novel HVAC flexibility quantification method based on a semidefinite programming (SDP) formulation. …

Honey Badger Optimizer For Extracting The Ungiven Parameters Of Pemfc Model: Steady-State Assessment, Hossam Ashraf, Sameh Osama Abdellatif Dr, Mahmoud Elkoly Dr, Attia Elfergany Prof

Electrical Engineering

In this work, a novel attempt is performed to optimally identify the seven ungiven parameters of the proton exchange membrane fuel cells (PEMFCs) steady-state model. A fitness function is adapted to reduce the sum of quadratic errors (SQEs) between the experimentally measured voltages and the corresponding computed values. A honey badger optimizer (HBO) is utilized to minimize the SQEs, exposed to a group of inequality bounds. Three test cases of well-known commercial PEMFCs units as benchmarking are elucidated and discussed over different steady-state operating conditions. Substantial comparisons to the other up-to-date optimizers published in the art-of-literature are provided to appraise …

Synergy Of Neuro-Fuzzy Controller And Tuna Swarm Algorithm For Maximizing The Overall Efficiency Of Pem Fuel Cells Stack Including Dynamic Performance, Hossam Ashraf, Mahmoud M. Elkholy Prof, Sameh O. Abdellatif, Attia A. El-Fergany Prof

Electrical Engineering

Recently, world endeavors are focused on promoting energy savings by operating both sources and loads at their maximum efficiency points. Thus, this paper presents a novel attempt to optimally determine the operating parameters of an isolated system comprising the proton exchange membrane fuel cells (PEMFCs) stack serving a variable load. A fitness function is adapted to maximize the PEMFCs stack’s efficiency using tuna swarm algorithm (TSA), subjected to set of inequality constraints. A well-known commercial type of PEMFCs stack namely Nedstack PS6 6 kW, are carefully studied over two TSA-based optimization scenarios. The first scenario aims at optimizing five operating …

Large-Scale Modeling And Dr Control Of Electric Water Heaters With Energy Star And Cta-2045 Control Types In Distribution Power Systems, Huangjie Gong, Evan S. Jones, A. H. M. Jakaria, Aminul Huque, Ajit Renjit, Dan Ionel

Power and Energy Institute of Kentucky Faculty Publications

The paper proposes a generalized energy storage (GES) model for battery energy storage systems (BESS), electric water heaters (EWH) and heating, ventilation, and air-conditioning (HVAC) systems to enable demand response control complying to Energy Star and CTA-2045 standards. The demand response control has been implemented in the DER integration testbed, which was originally developed by EPRI, to demonstrate that the “energy content” and “energy take” for BESS and EWH with mixing valve technology are comparable for typical residential ratings. A distribution power system was modeled using the modified IEEE 123-bus feeder system, measured residential loads, and EWH power simulated based …

Multi-Physics And Artificial Intelligence Models For Digital Twin Implementations Of Residential Electric Loads, Steven Poore, Rosemary E. Alden, Huangjie Gong, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Heating, ventilation, and air-conditioning (HVAC) and electric water heating (EWH) represent residential loads. Simulating these appliances for electric load forecasting, demand response (DR) studies, and human behavior analysis using physics-based models and artificial intelligence (AI) can further advance smart home technology. This paper explains the background of residential load modeling, starting with the concept of digital twin (DT) as well as the different types of methods. Two major types of appliance load monitoring (ALM) and their advantages/disadvantages are then discussed. This is followed by a review of multiple studies on residential load modeling, particularly for HVAC, EWH, and human behavior. …

Power Decoupling Control And Optimization For A Photovoltaic Inverter In D-Q Rotation Frame, Zhaoxia Yang

All Graduate Theses, Dissertations, and Other Capstone Projects

In the past decade, solar energy, the fastest growing renewable energy, has been a growing interest in integration to the utility grid. Power electronics converters play important role in renewable energy integration, e.g., integrate the distributed photovoltaic (PV) panels to the grid. In many applications, particularly in the residential area, a single-phase rather than three-phase inverter is used to regulate the voltage from one form to the other while tracking the maximum power point of the PV system. The input voltage and current are DC and its maximum power is desired to be a constant value. However, in the single-phase …

Techno-Economic Feasibility Of Electrifying Food Markets In Nigeria With Biogas Hybrid Mini-Grids, Demi Temitope Ogunwo

Cal Poly Humboldt theses and projects

This thesis explored the feasibility of electrifying a food market in an urban city in Nigeria with a hybrid biogas-powered mini-grid. Under the Energizing Economies Initiative of the Rural Electrification Agency of Nigeria, nine markets in the country currently receive constant access to electricity via hybrid mini-grid systems. As a majority of these systems are diesel-solar-battery systems, this thesis explored the use of biogas generators as a substitute for diesel generators in hybrid mini-grids for food markets. A fruit and vegetable market in Ketu, Lagos was used as a case study for the research. The research for this thesis was …

Stochastic Battery Soc Model Of Ev Community For V2g Operations Using Cta-2045 Standards, Huangjie Gong, Rosemary E. Alden, Dan Ionel

Power and Energy Institute of Kentucky Faculty Publications

An electric vehicle (EV) battery has large energy storage capacity in the context of residential total usage, and the potential to provide large energy reserves for Home energy Management (HEM) systems. In an electric distribution system, groups of EVs could provide vehicle-to-grid (V2G) service in response to control signals and enable virtual power plant (VPP) operation of the car batteries. The CTA-2045 standards were considered for integration of the EV controls into the HEM system for maximal interoperability with other appliances, such as residential battery, electric water heater, and heating, ventilation, and air conditioning (HVAC) system. The power distribution system …