Engineering Commons^™

Life Cycle Assessment Projection Of Photovoltaic Cells: A Case Study On Energy Demand Of Quantum Wire Based Photovoltaic Technology Research, Shilpi Mukherjee

Graduate Theses and Dissertations

With increasing clean-energy demand, photovoltaic (PV) technologies have gained attention as potential long-term alternative to fossil fuel energy. However, PV research and manufacture still utilize fossil fuel-powered grid electricity. With continuous enhancement of solar conversion efficiency, it is imperative to assess whether overall life cycle efficiency is also being enhanced. Many new-material PV technologies are still in their research phase, and life cycle analyses of these technologies have not yet been performed. For best results, grid dependency must be minimized for PV research, and this can be accomplished by an analytical instrument called Life Cycle Assessment (LCA).

LCA is the …

Analysis And Optimization Of The Scheffler Solar Concentrator, Simone Alberti

Master's Theses

The Scheffler reflector is a new solar concentrator design which maintains a fixed focus while only having a single axis tracking mechanism. This design makes the construction and operation of high temperature solar concentrators accessible to developing nations. In this project, I wrote computer simulation codes to better understand the dynamics and the effect of deformation or deviations from ideal conditions in order to define necessary manufacturing and operational tolerances. These tools and knowledge drove the prototyping of new reflector concepts by myself and other students on my team. A fiberglass prototype was able to drive the cost of a …

Transimpedance Amplifier For Polymer Photodiodes, Sheridan Knighton

Electrical Engineering

Dr. Braun’s students in the Polymer Electronics Lab currently have a way to measure the light intensity from their light emitting devices however it consumes an unnecessary amount of space and power. I offer to improve upon the existing transimpedance circuit that Dr. Braun currently uses, reducing the total space occupied by the circuit and the power consumption of the current setup. The transimpedance circuit measures the incidence light intensity from the polymer-based photo detector and outputs an accurate, discrete, and measurable voltage. The current setup however utilizes two 20V wall warts for the positive and negative rails of the …

Solar Power Deployment: Forecasting And Planning, Mohana Shandal Alanazi

Electronic Theses and Dissertations

The rapid growth of Photovoltaic (PV) technology has been very visible over the past decade. Recently, the penetration of PV plants to the existing grid has significantly increased. Such increase in the integration of solar energy has brought attention to the solar irradiance forecasting. This thesis presents a thorough research of PV technology, how solar power can be forecasted, and PV planning under uncertainty.

Over the last decade, the PV was one of the fastest growing renewable energy technologies. However, the PV system output varies based on weather conditions. Due to the variability and the uncertainty of solar power, the …

Solar Sail Trajectory Design In The Earth-Moon Circular Restricted Three Body Problem, Ashwati Das

Open Access Theses

The quest to explore the Moon has helped resolve scientific questions, has spurred leaps in technology development, and has revealed Earth's celestial companion to be a gateway to other destinations. With a renewed focus on returning to the Moon in this decade, alternatives to chemical propulsion systems are becoming attractive methods to efficiently use scarce resources and support extended mission durations. Thus, an investigation is conducted to develop a general framework, that facilitates propellant-free Earth-Moon transfers by exploiting sail dynamics in combination with advantageous transfer options offered in the Earth-Moon circular restricted multi-body dynamical model. Both periodic orbits in the …

Electrical & Computer Engineering News, Georgia Southern University

Electrical & Computer Engineering News (2014-2023)

• EE Department wins Sustainability Grant for Solar Vehicle Research

Solar And Visible Light Driven Photocatalysis For Sacrificial Hydrogen Generation And Water Detoxification With Chemically Modified Ti02, Pankaj Chowdhury

PC

Photocatalysis is a recognized approach where light energy is employed to excite the semiconductor material producing electron/hole pair which eventually involves in the detoxification of pollutants and/or water splitting producing hydrogen. Existing photocatalysts suffer from poor activity or no activity in visible light irradiation which restricts them from solar light utilization. This work is focused on two key applications of photocatalysis (i) sacrificial hydrogen generation, and (ii) phenol degradation in visible and/or solar light. Platinum was loaded on TiO2 photocatalyst by solar photo-deposition method. Eosin Y dye was used as a sensitizer for sensitization of platinum loaded TiO2 photocatalyst. The …

All Purpose Mobile Gps, James C. Smith, Matt Weege, Kevin Peters

Electrical Engineering

The aim of the All Purpose Mobile GPS (The System) is to create a GPS tracking device that can accurately record location and calculate velocity, distance traveled and elevation change even when the satellite signal is lost. This data can later overlay on existing internet-based maps illustrating a trip to oneself or others. The portable tracker consumes very little power achieving several days’ worth of power in a single charge. A solar cell provides a quick battery boost in a pinch. SD Card storage increases compatibility with computers and other forms of data transfer. Data processing, such as viewing the …

Application Of A High-Performance Optically Enhanced Solar Thermal Collector System, Timothy H. Cameron

Honors Theses

In an effort to make Union College a more environmentally friendly campus, this research project focuses on the application of Union’s liquid-based solar thermal collector system. The motivation for this research project is due to the increasing demand for renewable energy sources in order to decrease our society’s dependence on fossil fuels. The system features nine, 16-tube, evacuated tube solar modules which absorb radiant solar energy from the sun. Through a two loop system, thermal energy is stored in water within two-80 gallon storage tanks. This research project involves the design, construction, and analysis of two applications in order to …

Bike Safe: An Automatic Turn Signal System, Betty He Chan, Ricardo Alberto Duran

Electrical Engineering

Bicycles are vehicles that do not require a license to operate and share the road with cars, motorcycles, and other fast moving vehicles. An improper lane change from a bicyclist, such as one without any warning, can lead to great injury or death (especially after sundown). Bike Safe addresses this safety concern by providing a low-cost device that mimics the warning system motorists’ use every day. The system consists of a red brake light and amber turning signal lights that mounts to the rear of the bike, as well as a white headlamp that mounts to the front handlebars. The …

Retrofitting Two Solar Hot Water Systems For Year Round Operation, Zachary A. Cook

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Solar energy in a variety of applications is again becoming more widely used. Solar collectors have been installed during the construction of two Utah State University buildings: Wetlands Discovery located in Kaysville, Utah and Swaner Nature Preserve located in Park City, Utah. While these systems are capable of capturing a significant amount of solar energy, problems have been encountered when the demand is less than the system’s capacity. This project report documents the problems encountered while operating the two solar water heating systems and how the systems were modified to be operational year round under typical operating conditions. The peak …

Gis-Based Suitability Modeling And Multi-Criteria Decision Analysis For Utility Scale Solar Plants In Four States In The Southeast Us, Kata Tisza

All Theses

Photovoltaic (PV) development shows significantly smaller growth in the Southeast U.S., than in the Southwest; which is mainly due to the low cost of fossil-fuel based energy production in the region and the lack of solar incentives. However, the Southeast has appropriate insolation conditions (4.0-6.0 KWh/m2/day) for photovoltaic deployment and in the past decade the region has experienced the highest population growth for the entire country. These factors, combined with new renewable energy portfolio policies, could create an opportunity for PV to provide some of the energy that will be required to sustain this growth. The goal of the study …

A Nonconjugated Bridge In Dimer-Sensitized Solar Cells Retards Charge Recombination Without Decreasing Charge Injection Efficiency, Kenji Sunahara, Matthew J. Griffith, Takayuki Uchiyama, Pawel Wagner, David L. Officer, Gordon G. Wallace, Attila J. Mozer, Shogo Mori

Gordon Wallace

Dye sensitized solar cells (DSSCs) employing a dimer porphyrin, which was synthesised with two porphyrin units connected without conjugation, have shown that both porphyrin components can contribute to photocurrent generation, that is, more than 50 % internal quantum efficiency. In addition, the open-circuit voltage (Voc) of the DSSCs was higher than that of DSSCs using monomer porphyrins. In this paper, we first optimized cell structure and fabrication conditions. We obtained more than 80% incident photon to current conversion efficiency from the dimer porphyrin sensitized DSSCs and higher Voc and energy conversion efficiency than monomer porphyrin sensitized solar cells. To examine …

Novel Nanographene/Porphyrin Hybrids-Preparation, Characterization, And Application In Solar Energy Conversion Schemes, Daniel Kiessling, Ruben D. Costa, Georgios Katsukis, Jenny Malig, Fabian Lodermeyer, Sebastian Feihl, Alexandra Roth, Leonie Wibmer, Matthias Kehrer, Michel Volland, Pawel W. Wagner, Gordon G. Wallace, David L. Officer, Dirk M. Guldi

Gordon Wallace

Four novel nanographene/porphyrin hybrids were prepared, characterized, and probed in solar energy conversion schemes. Exfoliation of graphite by means of immobilizing four different porphyrins onto the basal plane of graphene is accompanied by distinct electronic interactions in both the ground and the excited states. In the ground state, a strong loss in oscillator strength goes hand-in-hand with a notable broadening of the porphyrin transitions and, as such, attests to the shift of electron density from the electron donating porphyrins to nanographene. In the excited state, a nearly quantitative quenching of the porphyrin fluorescence is indicative of full charge transfer. The …

Cation Exchange At Semiconducting Oxide Surfaces: Origin Of Light-Induced Performance Increases In Porphyrin Dye-Sensitized Solar Cells, Matthew J. Griffith, Kenji Sunahara, Akihiro Furube, Attila J. Mozer, David L. Officer, Pawel Wagner, Gordon G. Wallace, Shogo Mori

Gordon Wallace

The origin of simultaneous improvements in the short-circuit current density (Jsc) and open-circuit voltage (Voc) of porphyrin dye-sensitized TiO2 solar cells following white light illumination was studied by systematic variation of several different device parameters. Reduction of the dye surface loading resulted in greater relative performance enhancements, suggesting open space at the TiO2 surface expedites the process. Variation of the electrolyte composition and subsequent analysis of the conduction band potential shifts suggested that a light-induced replacement of surface-adsorbed lithium (Li+) ions with dimethylpropylimidazolium (DMPIm+) ions was responsible for an increased electron lifetime by decreasing the recombination with the redox mediator. …

The Sun Also Rises: Prospects For Solar District Heating In The United States, Adam L. Reed, John S. Mccartney

Kevin L Doran

Renewable thermal energy remains a largely untapped resource in the United States, despite its low costs and growing popularity in many other countries and the pressing need to rapidly deploy and scale carbon-free energy sources in order to mitigate anthropogenic climate change. In this article, an energy attorney and a civil engineer collaborate to examine the prospects in the United States for solar district heating (SDH), a thermal technology that leverages economies of scale to provide zero-carbon, round-the-clock space and water heating (on average, the two largest components of building energy demand) to neighborhoods and commercial zones at costs competitive …

A Novel Microgrid Demand-Side Management System For Manufacturing Facilities, Terance J. Harper, William J. Hutzel, James C. Foreman, Aaron L. Adams, Athula Kulatunga

Purdue Polytechnic Masters Theses

Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable.

For this research, a manufacturing process that had approximately …

Modeling And Fault Detection In Dc Side Of Photovoltaic Arrays, Mohd Akram

Electronic Theses and Dissertations

Fault detection in PV systems is a key factor in maintaining the integrity of any PV system. Faults in photovoltaic systems can cause irrevocable damages to the stability of the PV system and substantially decrease the power output generated from the array of PV modules. Among'st the various AC and DC faults in a PV system, the clearance of the AC side faults is achieved by conventional AC protection schemes,the DC side, however , there still exists certain faults which are difficult to detect and clear. This paper deals with the modeling, detection and classification of these types of DC …

An Approach For Online Assessment Of Rooftop Solar Pv Impacts On Low-Voltage Distribution Networks, Md Jan-E- Alam, Kashem Muttaqi, Darmawan Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

Assumption-based offline analysis tools may not be able to provide sufficient and accurate information for the corrective decision making to mitigate solar photovoltaic (PV) impacts in the future distribution grids. This is mainly due to the increasing penetration level of intermittent power generation resources and also the fluctuating behavior of consumer demand. Online assessment tools can assist to manage PV impacts and aid to mitigate those on a real-time basis. This paper proposes an approach for online assessment of rooftop PV impacts on low-voltage (LV) networks using real-time network data. A variable-width sliding window will be used to provide the …

A Novel Approach For Ramp-Rate Control Of Solar Pv Using Energy Storage To Mitigate Output Fluctuations Caused By Cloud Passing, M J. E Alam, K M. Muttaqi, D Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

The variability of solar irradiance with a high ramp-rate, caused by cloud passing, can create fluctuation in the PV output. In a weak distribution grid with a high PV penetration, this can create significant voltage fluctuations. Energy storage devices are used to smooth out the fluctuation using traditional moving average control. However, moving average does not control the ramp-rate directly; rather the ramp-rate depends on previous values of PV output. This paper proposes a strategy where the ramp-rate of PV panel output is used to control the PV inverter ramp-rate to a desired level by deploying energy storage (which can …

Solar Pv And Battery Storage Integration Using A New Configuration Of A Three-Level Npc Inverter With Advanced Control Strategy, Hamid Teymour Ghasemabadi, Danny Soetanto, Kashem M. Muttaqi, Philip Ciufo

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, a novel configuration of a three-level neutral-point-clamped (NPC) inverter that can integrate solar photovoltaic (PV) with battery storage in a grid-connected system is proposed. The strength of the proposed topology lies in a novel, extended unbalance three-level vector modulation technique that can generate the correct ac voltage under unbalanced dc voltage conditions. This paper presents the design philosophy of the proposed configuration and the theoretical framework of the proposed modulation technique. A new control algorithm for the proposed system is also presented in order to control the power delivery between the solar PV, battery, and grid, which …

Highly Connected Hierarchical Textured Tio2 Spheres As Photoanodes For Dye-Sensitized Solar Cells, Jianjian Lin, Andrew Nattestad, Hua Yu, Yang Bai, Lianzhou Wang, S X. Dou, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

We present a new type of microstructured TiO2 sea urchin-like assembly, composed of high aspect-ratio nanosheets. We also demonstrate the applicability of these structures as photoanodes in dye-sensitized solar cells, with 9.0% conversion efficiency realized, a considerable improvement over the commercial Dyesol paste (8.2%) under the same conditions. We reveal that this new TiO2 nanostructure is beneficial to enhanced dye loading and efficient light scattering. In particular, the interpenetrating individual sheets of the spheres result in more intimate interparticle connections and provide efficient electron transfer pathways.

Enhanced Performance Of Dye-Sensitized Solar Cells Using Carbazole-Substituted Di-Chromophoric Porphyrin Dyes, Long Zhao, Pawel Wagner, Anastasia Elliott, Matthew Griffith, Tracey M. Clarke, Keith C. Gordon, Shogo Mori, Attila Mozer

Australian Institute for Innovative Materials - Papers

The purpose of this work is to investigate the origin of improved photovoltaic performance of a series of di-chromophoric carbazole-substituted porphyrin dyes employed as sensitizers in dye-sensitized solar cells. Five di-chromophoric zinc porphyrin dyes with the same porphyrin core, a carbazole unit attached in the meso-position through a phenylethenyl linkage, and substituents spanning a range of electron affinities, in an attempt to tune the electronic level of the carbazole unit, have been synthesized (CZPs). Density functional theory (DFT) calculations predicted the nature of the electronic transitions observed in the CZP systems, showing a large degree of orbital mixing. In contrast, …

Integrating A Triplet-Triplet Annihilation Up-Conversion System To Enhance Dye-Sensitized Solar Cell Response To Sub-Bandgap Light, Andrew Nattestad, Yuen Yap Cheng, R Macqueen, Gordon G. Wallace, Timothy Schmidt

Australian Institute for Innovative Materials - Papers

The poor response of dye-sensitized solar cells (DSCs) to red and infrared light is a significant impediment to the realization of higher photocurrents and hence higher efficiencies. Photon up-conversion by way of triplet-triplet annihilation (TTA-UC) is an attractive technique for using these otherwise wasted low energy photons to produce photocurrent, while not interfering with the photoanodic performance in a deleterious manner. Further to this, TTA-UC has a number of features, distinct from other reported photon up-conversion technologies, which renders it particularly suitable for coupling with DSC technology. In this work, a proven high performance TTA-UC system, comprising a palladium porphyrin …

3d Hierarchical Rutile Tio2 And Metal-Free Organic Sensitizer Producing Dye-Sensitized Solar Cells 8.6% Conversion Efficiency, Jianjian Lin, Yoon-Uk Heo, Andrew Nattestad, Ziqi Sun, Lianzhou Wang, Jung Ho Kim, S X. Dou

Australian Institute for Innovative Materials - Papers

Three-dimensional (3D) hierarchical nanoscale architectures comprised of building blocks, with specifically engineered morphologies, are expected to play important roles in the fabrication of 'next generation' microelectronic and optoelectronic devices due to their high surface-to-volume ratio as well as opto-electronic properties. Herein, a series of well-defined 3D hierarchical rutile TiO2 architectures (HRT) were successfully prepared using a facile hydrothermal method without any surfactant or template, simply by changing the concentration of hydrochloric acid used in the synthesis. The production of these materials provides, to the best of our knowledge, the first identified example of a ledgewise growth mechanism in a rutile …