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Reduced Graphene Oxide (Rgo) Hollow Network Cages For High-Performance Electrochemical Energy Storage, Chi ZHANG, Xu-Jun HE, Gao-Ren LI 2016 School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China;

Reduced Graphene Oxide (Rgo) Hollow Network Cages For High-Performance Electrochemical Energy Storage, Chi Zhang, Xu-Jun He, Gao-Ren Li

Journal of Electrochemistry

The reduced graphese oxide (RGO) hollow network cages were synthesized via zinc oxide (ZnO) template-assisted electrodeposition. The as-prepared RGO hollow network cages exhibited the multi-level architectures, from nano sheets, porous structures, networks, to 3D microscaled hollow cages, which can simultaneously optimize transport of electroactive species, utilization rate of electrode material, and super capacitive performance. Electrochemical measurements confirmed the superior performance of RGO hollow network cages for supercapacitors (SCs), such as high Csp (393 F⋅g-1 at 1.0 A⋅g-1), excellent rate capability (21.2% Csp loss from 1.0 to 20 A⋅g-1), and superior cycling stability (< 1% Csp loss after 10000 cycles).


Developments Of Photo-Assisted Fuel Cells, Ling-ling ZHANG, Shao-jun DONG 2016 niversity of Chinese Academy of Sciences, 100049, Beijing, China

Developments Of Photo-Assisted Fuel Cells, Ling-Ling Zhang, Shao-Jun Dong

Journal of Electrochemistry

The exploitation and utilization of fossil fuels have led to serious energy crisis and environmental pollution. In this case, the development of renewable energy is an alternative to traditional energy consumption. Fuel cells (FCs) can convert chemical energy into electricity via the electrochemical reaction, which is green and environment-friendly. Photo-assisted FCs integrate photo-responsive components into FCs, leading to the dual routes of energy conversion including light energy to electricity and chemical energy to electricity, and thus, improving the energy utilization efficiency. The development of photo-assisted FCs is significant for practical application and promising to solve the coming energy crisis. In …


Energy Consumption Prediction With Big Data: Balancing Prediction Accuracy And Computational Resources, Katarina Grolinger, Miriam AM Capretz, Luke Seewald 2016 Western University

Energy Consumption Prediction With Big Data: Balancing Prediction Accuracy And Computational Resources, Katarina Grolinger, Miriam Am Capretz, Luke Seewald

Electrical and Computer Engineering Publications

In recent years, advances in sensor technologies and expansion of smart meters have resulted in massive growth of energy data sets. These Big Data have created new opportunities for energy prediction, but at the same time, they impose new challenges for traditional technologies. On the other hand, new approaches for handling and processing these Big Data have emerged, such as MapReduce, Spark, Storm, and Oxdata H2O. This paper explores how findings from machine learning with Big Data can benefit energy consumption prediction. An approach based on local learning with support vector regression (SVR) is presented. Although local learning itself is …


Bringing Electricity To Alafiarou: The Solar Microgrid Project, Nicolas Metais, Jacob Leatherberry 2016 Santa Clara University

Bringing Electricity To Alafiarou: The Solar Microgrid Project, Nicolas Metais, Jacob Leatherberry

Electrical and Computer Engineering Senior Theses

Despite the great technological advancements and discoveries that have been made throughout the last century, 1.2 billion people still live without access to electricity, 95% of which live in Sub-Saharan Africa and developing Asia.1 In this paper, we discuss how we designed and implemented a self-sustaining, affordable and highly replicable solar microgrid in order to accelerate the electrification of rural communities in the most environmentally conscious way possible. Our project focused on developing a microgrid for a small community of 10 households in rural Benin that previously had no access to electricity. We travelled to this village in December of …


A Utility-Scale Deployment Project Of Behind-The-Meter Energy Storage For Use In Ancillary Services, Energy Resiliency, Grid Infrastructure Investment Deferment, And Demand-Response Integration, Joseph Nathanael Wilson 2016 Portland State University

A Utility-Scale Deployment Project Of Behind-The-Meter Energy Storage For Use In Ancillary Services, Energy Resiliency, Grid Infrastructure Investment Deferment, And Demand-Response Integration, Joseph Nathanael Wilson

Dissertations and Theses

Electric utilities are increasingly incentivized to integrate new renewable energy generation resources to their systems; however, operations-related issues arise due to the non-dispatchable and stochastic nature of these renewable energy sources. These characteristics lead to a variety of issues for utilities, among which are voltage fluctuations, balancing dispatch against ramping events, short-duration power fluctuations, and the need to invest in peaking generation facilities just to accommodate the renewable energy. A traditional solution to these issues is to employ renewable generation-following techniques using either newly constructed gas peaking plants, or by shifting existing generation resources to this following responsibility. Unfortunately, use …


The Investigation And Optimization Of A Two-Heat-Pump System Incorporating Thermal Storage For Shaping Residential Heating Load, Emily Lord Barrett 2016 Portland State University

The Investigation And Optimization Of A Two-Heat-Pump System Incorporating Thermal Storage For Shaping Residential Heating Load, Emily Lord Barrett

Dissertations and Theses

Portland General Electric has proposed coupling one or more water tanks with two heat pumps in order to perform load-shifting in residential customer heating and cooling applications. By using the water tanks as a thermal storage unit, this project attempts to partially decouple energy consumption from generation to provide peak demand reduction and to better facilitate the integration of variable renewable energy resources. A scoping study was performed to evaluate the potential impact of this project if implemented in single family homes in Portland, Oregon. This study revealed that the system could provide meaningful savings in the cost of electricity …


Wireless Mesh Networks For Scada Systems, Zachary Weisman 2016 California Polytechnic State University, San Luis Obispo

Wireless Mesh Networks For Scada Systems, Zachary Weisman

Computer Engineering

No abstract provided.


Arc Fault Circuit Interrupter Development For Residential Dc Electricity, Cassidy Alan Aarstad 2016 California Polytechnic State University, San Luis Obispo

Arc Fault Circuit Interrupter Development For Residential Dc Electricity, Cassidy Alan Aarstad

Master's Theses

The following technical report describes the development and testing of an arc fault circuit interrupter (AFCI) for DC circuits operating primarily at 48 volts. We have identified an effective method for determining when arcing is occurring. Our method is primarily based on comparing the frequency spectrum of current flowing through the circuit during an arcing event to a known characteristic spectrum. Once an arc has been identified, our interrupter is capable of responding adequately to eliminate the arc. Hardware tests show the AFCI developed in this thesis responded, in all test cases, within 2 seconds of an arc fault occurrence. …


Modelling And Energy Management Optimisation Of Battery Energy Storage System Based Photovoltaic Charging Station (Pv-Cs) For University Campus, Ayda Esfandyari, Brian Norton, Michael Conlon 2016 Technological University Dublin

Modelling And Energy Management Optimisation Of Battery Energy Storage System Based Photovoltaic Charging Station (Pv-Cs) For University Campus, Ayda Esfandyari, Brian Norton, Michael Conlon

Conference Papers

As utilization of Photovoltaic Charging Stations (PV-CS) that generate clean electricity from the sun increase, Technological University Dublin (DIT) adopts this application for accommodating the required charge of small campus Battery Electric Vehicles (BEVs). This paper presents the virtual simulation of the 10.5 kW Battery Energy Storage System (BESS) based PV-CS model. Transient System Simulation (TRNSYS) built-in climatic data and modular structure properties were adopted to replicate the experimentally proposed PV-CS, where special attention was paid to the electrical measurments and energy flow signals. The objective was set to model the PV-CS system, formulate an energy managment optimisation and justify …


Automatic Water Pump Controller, Alam D. Salguero, Kyle Russell Marquez Weeks 2016 California Polytechnic State University, San Luis Obispo

Automatic Water Pump Controller, Alam D. Salguero, Kyle Russell Marquez Weeks

Electrical Engineering

In countries including Indonesia, Mexico, Guatemala, and El Salvador, a city water authority supplies the clean water and pumps it into large ground-level storage tanks. A resident’s water pump then pumps the water to a water tank on top of his/her house. When the water level in the ground-level storage tank becomes too low, the pump siphons air and shuts down, requiring a resident to manually prime the water pump to get it running again. Residents struggle to monitor the water level of the tanks effectively and keep the pump running properly. To remedy the issue, the Automatic Water Pump …


Energy Harvesting From Exercise Machines Buck-Boost Dc Dc Converter With The Lt8705 Controller, Ryan Matteo 2016 California Polytechnic State University, San Luis Obispo

Energy Harvesting From Exercise Machines Buck-Boost Dc Dc Converter With The Lt8705 Controller, Ryan Matteo

Electrical Engineering

In order to increase sustainability and save money, the Energy Harvesting from Exercise Machines (EHFEM) system uses human supplied energy to self-power exercise equipment such as spin bikes, elliptical trainers, ergometers, etc. This document covers the design and implementation of a Buck-Boost DC-DC converter using the LT8705 controller into the EHFEM system. This project improves upon the overall efficiency of the Buck-Boost Converter designed by past groups working on the EHFEM system.


Transformer And Motor Protection Scheme, Bijan Vakilifathi 2016 California Polytechnic State University, San Luis Obispo

Transformer And Motor Protection Scheme, Bijan Vakilifathi

Electrical Engineering

No abstract provided.


Solar Generation's Impact On Fault Current, Kody Heppner 2016 California Polytechnic State University, San Luis Obispo

Solar Generation's Impact On Fault Current, Kody Heppner

Electrical Engineering

California is paving the road for other states with the capacity of solar installations for residential and commercial entities. The added capacity of solar generation to the state's electric grid has an impact on power flow and fault currents. This project looks at the impact of solar installations on fault currents. Feeders with added residential rooftop solar and larger commercial solar installations may impact the system differently than a large, utility-sized solar installation. This project looks at the impact of both cases on the magnitude of fault current during many different fault types and locations that can occur within a …


Integration Of Sel Relays To Provide Motor, Transmission Line, And Transformer Protection, Christopher Ewing, Bryce Keefer 2016 California Polytechnic State University, San Luis Obispo

Integration Of Sel Relays To Provide Motor, Transmission Line, And Transformer Protection, Christopher Ewing, Bryce Keefer

Electrical Engineering

The objective of this project is to familiarize the performers with the principles of operation of the Schweitzer Engineering Laboratories (SEL) protective relays in both normal and fault conditions. The SEL-587, SEL-311L and SEL-710 microprocessor-based relays are used to provide protection for a system composed of transformers, simulated transmission lines and a 3-phase induction motor. Each of these relays provides protection by sending a trip signal to local breakers upon sensing a fault condition. The SEL-587 provides overcurrent and differential protection for a 3-phase transformer, while the SEL-311L provides differential and distance protection for a transmission line, and negative sequence. …


Micro-Inverter Improvement For The Energy Harvesting From Exercise Machine Project, James Ralston 2016 California Polytechnic State University, San Luis Obispo

Micro-Inverter Improvement For The Energy Harvesting From Exercise Machine Project, James Ralston

Electrical Engineering

The Energy Harvesting from Exercise Machines (EHFEM) project at California Polytechnic State University consists of several different projects coming together to add human generated power to the grid. This project focuses on implementing a more efficient micro-inverter. The micro-inverter used to convert DC to AC voltage requires up to 5 minutes before the conversion process begins. This time lag significantly diminishes the power produced from an exercising individual. Research of micro-inverters approved by the CEC introduces desirable micro-inverters, available for use in California, to the EHFEM project. Testing the two most desirable micro-inverters found from research allows for quantifying of …


Rf Power Harvesting Rectenna, Jimmy Tang, Raymond Phu, Tom Geranios, Benjamin Muñoz 2016 California Polytechnic State University, San Luis Obispo

Rf Power Harvesting Rectenna, Jimmy Tang, Raymond Phu, Tom Geranios, Benjamin Muñoz

Electrical Engineering

Sustainability is one of today's primary engineering objectives. This principle involves system design that minimizes environmentally harmful energy emissions and resource consumption, and maximizes renewable energy practices [1]. Communication antennas transmit wireless signals that can be converted into usable energy. The Rectenna system described in this report, shown in Figure 1, was designed to accomplish this energy conversion, with -5dBm (316µW) minimum power at the rectifier input. Since typical ambient signal power is in the -70dBm (0.1nW) range, the proposed system could only convert passive, relatively high-power microwave band AC signals to DC. The Rectenna system was designed for 1.9GHz …


Low-Frequency Series Loaded Resonant Inverter Characterization, Alfredo Medina 2016 California Polytechnic State University, San Luis Obispo

Low-Frequency Series Loaded Resonant Inverter Characterization, Alfredo Medina

Master's Theses

Modern power systems require multiple conversions between DC and AC to deliver power from renewable energy sources. Recent growth in DC loads result in increased system costs and reduced efficiency, due to redundant conversions. Advances in DC microgrid systems demonstrate superior performance by reducing conversion stages. The literature reveals practical DC microgrid systems composed of wind and solar power to replace existing fossil fuel technologies for residential consumers. Although higher efficiencies are achieved, some household appliances require AC power; thus, the need for highly efficient DC to AC converters is imperative in establishing DC microgrid systems. Resonant inverter topologies exhibit …


The Effects Of Phosphonic Acids In Dye-Sensitized Solar Cells, Keith Edward James 2016 Portland State University

The Effects Of Phosphonic Acids In Dye-Sensitized Solar Cells, Keith Edward James

Dissertations and Theses

Novel methods for the construction of dye-sensitized solar cells (DSSCs) were developed. A thin dense underlayer of TiO2 was applied on fluorine-doped tin oxide (FTO) glass using as a precursor Tyzor AA-105. Subsequently a mesoporous film of P-25 TiO2 was applied by spreading a suspension uniformly over the surface of the underlayer and allowing the plate to slowly dry while resting on a level surface. After sintering at 500° C slides were treated with TCPP as a sensitizing dye and assembled into DSSCs. A novel method was used to seal the cells; strips of Parafilm® were used as …


Event Detection Using Correlation Within Arrays Of Streaming Pmu Data, Jordan Landford 2016 Portland State University

Event Detection Using Correlation Within Arrays Of Streaming Pmu Data, Jordan Landford

Dissertations and Theses

This thesis provides a synchrophasor data analysis methodology that leverages both statistical correlation techniques and a statistical distribution in order to identify data inconsistencies, as well as power system contingencies. This research utilizes archived Phasor Measurement Unit (PMU) data obtained from the Bonneville Power Administration in order to show that this methodology is not only feasible, but extremely useful for power systems monitoring, decision support, and planning purposes.

By analyzing positive sequence voltage angles between a pair of PMUs at two different substation locations, an historic record of correlation is established. From this record, a Rayleigh distribution of correlation coefficients …


Reflective Efficiencies Of Materials For Applications Of Bifacial Solar Cells, Michael Metter 2016 Linfield College

Reflective Efficiencies Of Materials For Applications Of Bifacial Solar Cells, Michael Metter

Senior Theses

The bifacial solar cell is superior to its monofacial predecessor due to its ability to convert both incident light on top and reflected light from below into energy. The scattering of the reflected light is affected by the property of the material on which it is interacting. To date, little work has been contributed to studying the properties of these materials to determine optimal quantities for bifacial solar cells. In the first experiment, reflective efficiencies compared to the angle of reflection were explored for different grit of sandpaper in order to develop an understanding of how surface texture impacts reflectivity. …


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