Power and Energy Commons^™

Economic Challenges And Optimisation Of Ocean Energy Electrical Systems, Fergus Sharkey

Books/Book chapters

No abstract provided.

An Investigation Into Energy Consumption And Existing Energy Management Practices In A Dublin Sports Centre, Colin J. Conway

Dissertations

Rising energy costs are a concern to all businesses but especially to those who have a large energy demand. Sports centres with swimming pools have large requirements for heat and electricity in order to maintain thermal comfort within the pool and surrounding areas.

Sports centres which were built in the 1970s were designed at a time when energy was cheap and many of today’s control strategies and energy efficiency measures were unavailable.

This project is an investigation into the electrical and thermal consumption of the Tallaght Sports Complex. The Tallaght Sports Complex was built in the 1970s and is lacking …

An Evaluation Of Seawater Pumped Hydro Storage For Regulating The Export Of Wind Energy To The National Grid, Eoin D. Mclean

Dissertations

Hydroelectric power generation has been in use for a very long time. From the earliest watermills to the current large scale Hydro power plants, this is a technology that is proven to be reliable and commercially viable. The use of wind energy to provide mechanical power for the purpose of turning a rotor is also not a new concept.Four years ago TCD Professor of Applied Physics Igor Shvets conceived the idea of solving Ireland’s energy crisis by taking these two proven renewable technologies and combining them. (McGreevey, 2012) The spirit of Ireland initiative seeks to resolve the biggest issues facing …

Neural Network Based Control Of Integrated Recycle Heat Exchanger Superheaters In Circulating Fluidized Bed Boilers, David D. Biruk

UNF Graduate Theses and Dissertations

The focus of this thesis is the development and implementation of a neural network model predictive controller to be used for controlling the integrated recycle heat exchanger (Intrex) in a 300MW circulating fluidized bed (CFB) boiler. Discussion of the development of the controller will include data collection and preprocessing, controller design and controller tuning. The controller will be programmed directly into the plant distributed control system (DCS) and does not require the continuous use of any third party software.

The intrexes serve as the loop seal in the CFB as well as intermediate and finishing superheaters. Heat is transferred to …

Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The goal of this dissertation research is to develop online nonintrusive condition monitoring and fault detection methods for wind turbine generators (WTGs). The proposed methods use only the current measurements that have already been used by the control and protection systems of WTGs; no additional sensors or data acquisition devices are needed. Current-based condition monitoring and fault detection techniques have great economic benefits and the potential to be adopted by the wind energy industry. However, there are challenges in using current measurements for wind turbine condition monitoring and fault detection. First, it is a challenge to extract WTG fault signatures …

Advances And Challenges Of Intermediate Temperature Solid Oxide Fuel Cells: A Concise Review, Sanping Jiang

Journal of Electrochemistry

Fuel cell is an electrochemical energy conversion device to directly convert the chemical energy of fuels to electricity. Among all types of fuel cells, solid oxide fuel cells (SOFCs) operating at intermediate temperatures of 600~800 ^oC offer an attractive option that is much more fuel flexible than low temperature fuel cells such as proton exchange membrane fuel cells, and is suitable for a wide range of applications. However, two main challenges remain towards the commercial viability and acceptance of the SOFC technologies: the cost and durability. Both are critically dependent on the process, fabrication, performance, chemical and microstructural stability …

Ternary Alloy Electrocatalysts For Oxygen Reduction Reaction, Jin Luo, Lefu Yang, Binghui Chen, Chuanjian Zhong

Journal of Electrochemistry

Proton exchange membrane fuel cell represents an important electrochemical energy conversion device with many attractive features in terms of efficiency of energy conversion and minimization of environmental pollution. However, the large overpotential for oxygen reduction reaction at the cathode and the low activity, poor durability and high cost of platinum-based catalysts in the fuel cells constitute a focal point of major barriers to the commercialization of fuel cells. The development of nanostructured catalysts shows promises to addresses some of the challenging problems. The ability to engineer the composition and nanostructure of nanoalloy catalysts is important for developing active, robust and …

Electrocatalytic Activity Of Palladium Nanocatalysts Supported On Carbon Nanoparticles In Formic Acid Oxidation, Jie Huang, Zhiyou Zhou, Yang Song, Xiongwu Kang, Ke Liu, Wancheng Zhou, Shaowei Chen

Journal of Electrochemistry

Palladium nanostructures were deposited onto carbon nanoparticle surface by a chemical reduction method. Transmission electron microscopic studies showed that whereas the resulting metal-carbon (Pd-CNP) nanocomposites exhibited a diameter of 20 to 30 nm, the metal components actually showed a cauliflower-like surface morphology that consisted of numerous smaller Pd nanoparticles (3 to 8 nm). Electrochemical studies showed that the effective surface area of the Pd-CNP nanoparticles was about 40% less than that of Pd black, possibly because the Pd nanoparticles were coated with a layer of carbon nanoparticles; yet, the Pd-CNP nanocomposites exhibited marked enhancement of the electrocatalytic activity in formic …

Electrocatalytic Oxidation Of Formic Acid On Pd/Ni Heterostructured Catalyst, Mingjun Ren, Liangliang Zou, Ju Chen, Ting Yuan, Qinghong Huang, Haifeng Zhang, Hui Yang, Songlin Feng

Journal of Electrochemistry

A Pd/Ni bimetallic nanostructured electrocatalyst was fabricated via a two-step reduction route. Owing to an epitaxial growth of Pd atoms on the surface of Ni nanoparticles, heterostructured Pd/Ni nanocomposites were formed and verified by high resolution transmission electron microscopy combined with energy-dispersion X-ray spectroscopy. X-ray diffraction confirmed that the as-prepared Pd/Ni nanocomposites possessed a single face-centered-cubic (fcc) Pd structure, probably due to a weaker diffraction intensity of metallic Ni and/or overlapping by that of Pd. The intrinsic catalytic activity on the Pd/Ni is higher than that on the Pd. Moreover, the durability of formic acid oxidation on the Pd/Ni was …

Adsorption And Electrooxidation Of Carbon Monoxide On Platinum Surfaces Modified With Sulfur, A. Mattox Mathew, W. Henney Matthew, Johnson Adam, Zou Shouzhong

Journal of Electrochemistry

Adsorbed sulfur is commonly considered as a reaction poison. However, small amounts of sulfur on platinum significantly increase the surface reactivity toward carbon monoxide (CO) electrooxidation. For the solution CO oxidation, the onset potential was shifted up to over 300 mV negative to that on S-free surface, and the extent of the negative potential shift increases with the sulfur coverage (X_s) up to about 0.6. The enhanced CO oxidation also depends on the solution pH. For the adsorbed CO, at low sulfur coverages (X_s < 0.3), the oxidation peak potential is about 40 mV negative to that of the corresponding clean Pt. However, at higher coverages, the peak potential is about 30 mV more positive. Surface-enhanced Raman spectra show that the adsorption of sulfur significantly redshifts the Pt-CO stretching frequency. These observations are explained by the weakening of the Pt-CO bond and the hindrance of CO diffusion by Sads.

Kinetic Study Of Photoelectrochemical Oxidation Of Lignin Model Compounds On Tio2 Nanotubes, Min Tian, Daniel Liba, Aicheng Chen

Journal of Electrochemistry

In this study, TiO₂ nanotubes were prepared via the electrochemical oxidation of titanium substrates in a non-aqueous electrolyte and their morphology and microstructures were examined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The photoelectrochemical oxidation of two lignin model compounds, 1-(3,4-dimethoxyphenoxy)-2-(2-methoxyphenoxy)-1,3-propanediol (DMP) and 3-hydroxy-1-(3,4-dimethoxyphenoxy)-2-(2-methoxyphenoxy)-1,3-propanone (HDM), was investigated. A new band appeared at ~304 nm during the photoelectrochemical oxidation of DMP. The rate of DMP intermediate formation was amplified with the increase of initial concentrations, while it was diminished with increased temperature. Despite the similarity in structure between HDM and DMP, there are only small increases in absorbance …

Electrochemical Performance Of Screen-Printed Composite Coatings Of Conducting Polymers And Carbon Nanotubes On Titanium Bipolar Plates In Aqueous Asymmetrical Supercapacitors, Xiaohang Zhou, George Z. Chen

Journal of Electrochemistry

Composites of conducting polymers (polypyrrole and polyaniline) with acid treated multi-walled carbon nanotubes were formulated into printable aqueous inks, with the aid of functional additives (benzethonium chloride as a surfactant with or without polyvinyl alcohol as a binder). The inks were screen-printed as fairly uniform coatings of various mass loading densities and areas (up to 75 mg cm^-2 and 100 cm²) on thin titanium plates (0.1 mm in thickness). These screen-printed plates were used to fabricate both unit cell and multi-cell stack of asymmetrical supercapacitors with screen-printed negative electrodes of activated carbon (pigment black) in aqueous electrolytes …

Condition-Dependent Risk Assessment Of Large-Scale Grid-Tied Photovoltaic Power Systems, Sherwin Li

Master's Theses

This thesis reviews the methods for evaluating the reliability of large PV systems and techniques for quantifying the impacts of PV interconnection on distribution system reliability. In addition, a comparative study is performed to evaluate the seasonal condition-dependent risk performance of central-inverter and string-inverter grid-tied PV power systems. Major contributions include: 1) risk analysis of seasonal impacts for string and centralized PV systems. Seasonal sensitivities of PV system risks to system structures, temperature variation, solar insolation, and capacitor equivalent series resistance are analyzed; and 2) the incorporation of the effect of operational conditions and the aging failure model into the …

The Architecture Selection, Design, And Discharge Modeling Of A Passive Compensation, Iron-Core, Two-Phase, Permanent Magnet Compulsator To Power A Small Railgun Platform, Collin Macgregor

Aerospace Engineering

The goal of this project was to design and build a compensated pulsed alternator, or compulsator, to power the Cal Poly Electromagnetic Railgun Mark 1.1. This project examines the feasibility of implementing mechanical pulsed power supplies for repeatable use with a railgun load for orbital debris hypervelocity testing. The final system architecture chosen was a passively compensated, iron-core, 2-phase, permanent magnet compulsator. The Cal Poly Compulsator will be capable of storing 45 kJ of mechanical energy with a peak operating speed of 5,000 rpm at 190 V. Theoretical calculations resulted in the following predicted electrical performance values: a peak output …

Performance And Cost Analysis Of A Structured Concrete Thermocline Thermal Energy Storage System, Matt Nicholas Strasser

Graduate Theses and Dissertations

Increasing global energy demands and diminishing fossil fuel resources have raised increased interest in harvesting renewable energy resources. Solar energy is a promising candidate, as sufficient irradiance is incident to the Earth to supply the energy demands of all of its inhabitants. At the utility scale, concentrating solar power (CSP) plants provide the most cost-efficient method of harnessing solar energy for conversion to electrical energy. A major roadblock to the large-scale implementation of CSP plants is the lack of thermal energy storage (TES) that would allow the continued production of electricity during the absence of constant irradiance. Sensible heat TES …

Smart Wall Plug Design For The Dc House Project, Edward Constant Sibal

Master's Theses

The DC House project at Cal Poly State University faces a challenge of supplying DC voltage to household appliances. Each appliance in the DC House constitutes a DC load that has a unique voltage and power rating, hence the need to develop a smart DC wall plug that will automatically adjust to the operating voltage required by any DC load. This thesis entails a proof of concept design of the smart DC wall plug which can automatically detect an appliance’s voltage rating. The design employs a dc-dc converter in conjunction with a microcontroller to sense load current to properly adjust …

Conductive Concrete For Electromagnetic Shielding – Methods For Development And Evaluation, Aaron P. Krause

Department of Computer Electronics and Engineering: Dissertations, Theses, and Student Research

This research investigates the development and evaluation innovative methods for the use of conductive concrete as an electromagnetic shield. New testing methods are developed to determine the best conductive components to use in the design of a concrete mixture for shielding that shows the best promise. The conductive concrete mixture has the potential to provide electromagnetic shielding that is cost-effective in terms of construction, operation, and maintenance compared to conventional approaches. Two testing methods, Small Sample Testing and Large Slab Testing, are developed based on standardized testing methods that have been modified for the testing of conductive concrete mixtures. As …

Energy Harvesting Of Human Kinetic Movement, David Marusiak, Julia Carrillo

Electrical Engineering

Development of kinetic energy scavenging applications from the human body necessitates additional research to assist in designating a mounting position for a potential device. A data acquisition system adequately provides a parametric average power comparison among four locations on the body (waist, upper arm, hand, and calf) for both a male and female subject. Experimentally, the hand-held device provided the highest average power. Thus, subsequent investigation at set speeds provides further analysis of the output’s characteristically linear behavior. The physical energy-harvesting device features a plastic tube casing wrapped with the stationary coiled wire through which a neodymium magnet oscillates. While …

Single-Phase High Efficiency Motor Testing, Marc Henry Perez

Electrical Engineering

A three-phase induction motor has higher efficiency than the single-phase motor counterpart. It is possible to run a three-phase motor with a single-phase source to develop a single-phase high efficiency system. The single-phase high efficiency motor, or SHE-motor, uses capacitor banks to operate at a balanced three phase induction motor using a single phase source. Unfortunately, this design has been limited, as it can only be balanced for one load configuration at a time. This provides the system to have maximum system performance. Due to this limitation in operations, it has proven to be non-ideal in commercial applications. It is …

Residential Grid-Tied With Battery Backup Photovoltaic System, Thomas Stobuagh

Electrical Engineering

When power outages occur, many homes are left without power for some time as they are dependent on the power grid. This project aims to design a residential grid tied battery backup photovoltaic system that will provide up to 7.2kW in an area that gets 5.36-5.49 kWh/m2/day [1] to support a home with an average daily usage of 28.4 kWh/day. To effectively use this system the house remains connected to the electric utility at all times, so any power needed above what the solar system can produce is simply drawn from the utility. It includes battery backup or uninterruptible power …