Engineering Commons^™

Photovoltaics And Battery-Based End-To-End Direct Current Sustainable Power Networks- Concept, Design, And Control, Vishwas Powar

All Dissertations

The consequences of climate change have emphasized the need for a power network that is centered around green, low-cost, and renewable sources of energy. Currently, photovoltaics (PV) and wind turbines are the only two technologies that can convert renewable energy from the sun and wind, respectively, into large-scale power for the electricity network. This dissertation aims to provide a novel solution to implement direct current-based architecture for PV generation coupled with lithium-ion battery storage in an efficient and sustainable manner. Such a power network can enable efficiency, reliability, low cost, and sustainability with minimum impact on the environment. The first …

Vertical Free-Swinging Photovoltaic Racking Energy Modeling: A Novel Approach To Agrivoltaics, Koami Soulemane Hayibo, Joshua M. Pearce

Electrical and Computer Engineering Publications

To enable lower-cost building materials, a free-swinging bifacial vertical solar photovoltaic (PV) rack has been proposed, which complies with Canadian building codes and is the lowest capital-cost agrivoltaics rack. The wind force applied to the free-swinging PV, however, causes it to have varying tilt angles depending on the wind speed and direction. No energy performance model accurately describes such a system. To provide a simulation model for the free-swinging PV, where wind speed and direction govern the array tilt angle, this study builds upon the open-source System Advisor Model (SAM) using Python. After the SAM python model is validated, a …

Quantitative, Photocurrent Multidimensional Coherent Spectroscopy, Adam Halaoui

Electronic Theses and Dissertations

Multidimensional coherent spectroscopy (MDCS) is a quickly growing field that has a lot of advantages over more conventional forms of spectroscopy. These advantages all come from the fact that MDCS allows us to get time resolved correlated emission and absorption spectra using very precisely chosen interactions between the density matrix and the excitation laser. MDCS spectra gives the researcher a lot of information that can be extracted purely through qualitative analysis. This is possible because state couplings are entirely separated on the spectra, and once we know how to read the data, we can see how carriers transport in the …

Spectroscopic Studies On Silicon And Chalcopyrite Materials For Solar Energy Applications, Amandee Hua

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation, silicon-based materials for photovoltaics and chalcopyrite-based materials for photoelectrochemical water splitting are investigated using various spectroscopic and microscopic techniques. Although silicon dominates the photovoltaic market, further improvement can be made by using an alternative low temperature passivation approach. Currently, thermally grown SiO2 passivation is commonly used for silicon solar cells. However, this technique requires high processing temperatures (>800 °C), which increases the thermal budget, potentially decreases the bulk quality of Si, and can lead to difficulties in implementing in production lines. Here, a S-based passivation approach is studied that require lower processing temperatures of ~550 °C. …

Understanding The Role Thin Film Interfaces Play In Solar Cell Performance And Stability, Mirra M. Rasmussen, Laura S. Bruckman, Ina T. Martin

Student Scholarship

As more efficient and cost-effective photovoltaic (PV) architectures are developed, solar becomes an ever more competitive and viable replacement for fossil fuels. Full grid electrification necessitates the development of efficient, reliable, cost-effective technologies - and there is room for many different kinds of PV in this expanding market. The practical challenges and constraints of terawatt PV production have brought scalability and durability into sharp scientific focus. From a materials perspective, there are commonalities in the materials questions and challenges across different PV technologies. Whereas most PV technology is referred to by the absorber layer - e.g. silicon, or perovskite solar …

Statistical Analysis And Degradation Pathway Modeling Of Photovoltaic Minimodules With Varied Packaging Strategies, Sameera Nalin Venkat, Xuanji Yu, Jiqi Liu, Jakob Wegmueller, Jayvic Cristian Jimenez, Erika I. Barcelos, Hein Htet Aung, Roger H. French, Laura S. Bruckman

Faculty Scholarship

Degradation pathway models constructed using network structural equation modeling (netSEM) are used to study degradation modes and pathways active in photovoltaic (PV) system variants in exposure conditions of high humidity and temperature. This data-driven modeling technique enables the exploration of simultaneous pairwise and multiple regression relationships between variables in which several degradation modes are active in specific variants and exposure conditions. Durable and degrading variants are identified from the netSEM degradation mechanisms and pathways, along with potential ways to mitigate these pathways. A combination of domain knowledge and netSEM modeling shows that corrosion is the primary cause of the power …

Comparison Of Predicted And Measured Annual Performance Of A Roof-Top Grid-Connected Pv System In The Irish Climate, Chibuisi Chinasaokwu Okorieimoh, Brian Norton Prof, Michael Conlon Prof

Conference Papers

The problem of energy scarcity has reached a global scale as a result of the majority of energy production relying on non-renewable sources of energy. Solar photovoltaic cells use the photovoltaic effect to convert solar energy into electrical energy. Solar energy can reduce emissions of carbon dioxide (CO₂) associated with the generation from fossil fuels as the only CO₂ emissions are those embodied in their manufacture. A 268.8 m² area roof-top grid-connected PV system with a total capacity of 49.92kW_p was installed at Warrenpoint (54.11^oN and 6.26^oW) in Ireland. 192 “Renesola” …

Fabrication And Characterization Of Carbon Nanotube Metal Matrix Composites For Use In Photovoltaic Gridline Applications, Cayla M. Nelson

Nanoscience and Microsystems ETDs

Performance reliability is crucial for photovoltaic (PV) cells in both terrestrial and space-based applications. Electrical efficiency losses over time are heavily impacted by electrical losses due to microcracks within the cell structure and metallization failure. Mechanical stresses and thermal cycling of the device can lead to fracture of the current-carrying metal (Ag) lines on the surface of the device, significantly reducing output power. Incorporating carbon nanotubes (CNTs) into PV metal lines as a reinforcement, forming a CNT/Ag metal matrix composite (MMC), enhances the electrical and mechanical performance of the device. In this work the influence of CNT/Ag MMCs were explored …

Grid-Connected Renewable Energy Systems For Residential Hvac Load Management, Oscar Samuel Acosta

Open Access Theses & Dissertations

With an ongoing mission of utility operators to maintain a resilient and reliable power grid in the face of continuously increasing load demand, it is essential that advancements be made in developing both technology and methodology to help account for the increasing energy requirements. According to the U.S. Department of Energy (DOE) and Energy Information Administration (EIA), the residential end-use sector alone counted for 22% of all electricity used in the U.S. in 2020. Of this, approximately 32% of household electricity load is the direct result of air conditioning and space heating units (HVAC). One way to account for this …

Tailoring Interfaces And Composition For Stable And Efficient Perovskite Solar Cells, Hamza Javaid

Doctoral Dissertations

Metal halide perovskite solar cells (PSCs) have revolutionized the field of thin film photovoltaics. Within a decade, the power conversion efficiencies (PCEs) have increased at a phenomenal rate, rising from 3.8% to more than 25% in single-junction devices, moving them ahead of the current silicon-based technology. The high efficiencies of perovskite solar cells (PSCs) and their other unique properties arise from a combination of organic and inorganic components and electronic-ionic conduction, making them excellent candidates for a plethora of applications. However, PSCs face a significant—and ironic—roadblock to commercialization: these light-harvesting materials degrade under sunlight—the very condition they would need …

Perovskite Film Formation For Solar Cell Absorbers: Effects Of Substrate Modification, Mirra M. Rasmussen, Kyle M. Crowley, Ina T. Martin

Student Scholarship

As perovskite solar cell efficiencies have risen rapidly, practical constraints have made durability a critical concern. Whereas much attention has been paid to the development of the perovskite absorber layer, the charge transport layers can also be engineered to better the performance and stability of the device. This work uses the molecular modifier bromopropyltrimethoxysilane (BPTMS) to alter the interface between indium tin oxide (ITO, a common thin film solar cell transparent electrode) and methylammonium lead iodide (MAPbI3, a common perovskite absorber) to improve the morphology and stability of the perovskite absorber film. The substrate, molecular modifier, and perovskite film were …

Development Of A Low-Cost, Photovoltaic-Powered, Automated Water Recovery System, David E. Daley

Master's Theses

An existing water filtration system at the Channel Islands Marine & Wildlife Institute (CIMWI) wastes approximately 25 gallons of water per day rinsing out solid waste under light load. To reduce CIMWI’s water and energy consumption, an automated system was designed and built to recover the rinse water and return it to the existing filtration loop. Models for fluid system requirements, basic energy needs, and photo- voltaic energy generation were created to aid in component selection. Basic sensors and electronics were programmed in Python for use with a Raspberry Pi single board computer to collect and process water recovery data …

Decoupling The Effects Of Interfacial Chemistry And Grain Size In Perovskite Stability, Mirra M. Rasmussen, Kyle M. Crowley, Miranda S. Gottlieb, Geneviève Sauvé, Ina T. Martin

Student Scholarship

No abstract provided.

Performance And Economics Of Solar Inverters And Module Level Power Electronics In A 1 Mw Photovoltaic System, Maxwell Criswell

Biological and Agricultural Engineering Undergraduate Honors Theses

Photovoltaic solar panels convert sunlight to electricity in the form of direct current; therefore, a necessary component of every photovoltaic system is an inverter to convert the electricity to usable alternating current. There are various commercially available inverter technologies manufactured today such as microinverters, string inverters, and central inverters, as well as module level power electronic devices such as DC optimizers that are capable of improving system performance in string and central inverter systems. This thesis compares the performance and economics of five different inverter and module level power electronic systems through model simulation using Helioscope software. The five alternatives …

A Photoanode With Hierarchical Nanoforest Tio 2 Structure And Silver Plasmonic Nanoparticles For Flexible Dye Sensitized Solar Cell, Brishty Deb Choudhury, Chen Lin, Sk Md Ali Zaker Shawon, Javier Soliz-Martinez, Hasina Huq, Mohammed Jasim Uddin

Electrical and Computer Engineering Faculty Publications and Presentations

Due to unique photovoltaic properties, the nanostructured morphologies of TiO2 on flexible substrate have been studied extensively in the recent years for applications in dye sensitized solar cells (DSSCs). Microstructured electrode materials with high surface area can facilitate rapid charge transport and thus improve the light-to-current conversion efficiency. Herein we present an improved photoanode with forest like photoactive TiO2 hierarchical microstructure using a simple and facile hydrothermal route. To utilize the surface plasmon resonance (SPR) and hence increase the photon conversion efficiency, a plasmonic nanoparticle Ag has also been deposited using a very feasible photoreduction method. The branched structure of …

Renewable Energy Generation And Ghg Emission Reduction Potential Of A Satellitewater Reuse Plant By Using Solar Photovoltaics And Anaerobic Digestion, Jonathan R. Bailey, Saria Bukhary, Jacimaria R. Batista, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Wastewater treatment is a very energy-intensive process. The growing population, increased demands for energy and water, and rising pollution levels caused by fossil-fuel-based energy generation, warrants the transition from fossil fuels to renewable energy. This research explored the energy consumption offset of a satellite water reuse plant (WRP) by using solar photovoltaics (PVs) and anaerobic digestion. The analysis was performed for two types of WRPs: conventional (conventional activated sludge system (CAS) bioreactor with secondary clarifiers and dual media filtration) and advanced (bioreactor with membrane filtration (MBR)) treatment satellite WRPs. The associated greenhouse gas (GHG) emissions were also evaluated. For conventional …

Transmission-Level Impact Analysis Of Utility-Scale Solar Photovoltaic Systems And Battery Energy Storage Grid Support, Gerald W. Bankes Ii

Theses and Dissertations--Electrical and Computer Engineering

Solar photovoltaic energy generation is expected to grow dramatically in coming years in order to take advantage of renewable and clean sources of electricity. This thesis presents research on the impact of increasing solar PV penetration, specifically of large, utility-scale PV facilities, on transmission network performance. The development of Python programming tools for automation of power flow analysis is presented. A modified version of the IEEE 118-Bus test system is developed and modified to simulate increasing PV generation on the transmission system. The impacts on performance are analyzed trends are reported. Battery energy storage systems are studied in this thesis …

Modeling Energy Flows In Floating In-Pond Raceways Utilizing Solar Power Back-Up, Bo Smith

Theses and Dissertations--Biosystems and Agricultural Engineering

The In-pond Raceway (IPR) is a novel option for production aquaculture, depending on water moving devices to provide constant flow. Device failure may result in catastrophic fish loss, requiring power backup systems to mitigate risk in case of power outages. Because these systems must be dependable and many suitable locations are remote, off-grid solar photovoltaic (PV) systems with battery storage have been considered since they eliminate need for utility power. Such systems can be hard to size and expensive. This study modeled system requirements using an energy balance to determine whether systems could withstand varying loads based on climatological conditions. …

Annual Simulation Of Photovoltaic Retrofits Within Existing Parabolic Trough Concentrating Solar Powerplants, Nipun Goel, Hannah O'Hern, Matthew Orosz, Todd Otanicar

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Solar power for electricity production comes from either photovoltaics or concentrating solar power plants. The former has seen rapid growth and expansion due to the rapid fall in global prices, while the latter has seen moderate growth due to ability to cheaply store thermal energy for later use. Hybridization, or combining photovoltaics with concentrating solar power represents a potential way for lowering cost while enabling long term storage. Over 5 GW of capacity exist worldwide using parabolic trough style technology for concentrating solar power which presents a unique option for optimization in the form of a photovoltaic retrofit. While it …

Cost Analysis Of Optimized Islanded Energy Systems In A Dispersed Air Base Conflict, Jay F. Pearson, Torrey J. Wagner, Justin D. Delorit

Faculty Publications

The United States Air Force has implemented a dispersed air base strategy to enhance mission effectiveness for near-peer conflicts. Asset dispersal places many smaller bases across a wide geographic area, which increases resupply requirements and logistical complexity. Hybrid energy systems reduce resupply requirements through sustainable, off-grid energy production. This paper presents a novel hybrid energy renewable delivery system (HERDS) model capable of (1) selecting the optimal hybrid energy system design that meets demand at the lowest net present cost and (2) optimizing the delivery of the selected system using existing Air Force cargo aircraft. The novelty of the model’s capabilities …

Design Aspects, Energy Consumption Evaluation, And Offset For Drinking Water Treatment Operation, Saria Bukhary, Jacimaria Batista, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Drinking water treatment, wastewater treatment, and water distribution are energy-intensive processes. The goal of this study was to design the unit processes of an existing drinking water treatment plant (DWTP), evaluate the associated energy consumption, and then offset it using solar photovoltaics (PVs) to reduce carbon emissions. The selected DWTP, situated in the southwestern United States, utilizes coagulation, flocculation, sedimentation, filtration, and chlorination to treat 3.94 m3 of local river water per second. Based on the energy consumption determined for each unit process (validated using the plant’s data) and the plant’s available landholding, the DWTP was sized for solar PV …

A Multi-Criteria Logistics Analysis Of Photovoltaic Modules For Remote Applications, Nathan Thomsen [*], Dimitri Papazoglou, Torrey J. Wagner, Andrew J. Hoisington, Steven J. Schuldt

Faculty Publications

Reliable electrical power grids are frequently unavailable or inaccessible in remote locations, including developing nation communities, humanitarian relief camps, isolated construction sites, and military contingency bases. This often requires sites to rely on costly generators and continuous fuel supply. Renewable energy systems (RES) in the form of photovoltaic (PV) arrays and energy storage present a rapidly improving alternative to power these remote locations. Previous RES literature and PV optimization models focused on economics, reliability, and environmental concerns, neglecting the importance of logistics factors in remote installations. This paper proposes additional optimization variables applicable to remote PV systems and compares PV …

First-Principles Studies Of Anion Engineering In Functional Ceramics, Steven Timothy Hartman

McKelvey School of Engineering Theses & Dissertations

Ceramic materials display a wide variety of valuable properties, such as ferroelectricity, superconductivity, and magnetic ordering, due to the partially covalent bonds which connect the cations and anions. While many breakthroughs have been made by mixing multiple cations on a sublattice, the equivalent mixed-anion ceramics have not received nearly as much attention, despite the key role the anion plays in the materials’ properties. There is great potential for functional ceramics design using anion engineering, which aims to tune the materials properties by adding and removing different types of anions in existing classes of ceramic materials. In this dissertation, I present …

Improving Pv Module Efficiency Through Cooling, Ashley Cox

Chemical Engineering Undergraduate Honors Theses

The Solarbacks researched and designed a variety of cooling methods that could be used to improve the efficiency of photovoltaics. These cooling methods can be separated into two categories: active and passive methods. The active cooling method of hydraulic cooling and the passive cooling methods of heat sinks (fins), optical coatings, thermosyphons, phase change materials, and thermoelectric generators were all taken into consideration as potential cooling methods. Passive cooling methods were preferred because the use of electricity required for the cooling mechanism would reduce the net electricity and subsequent profit from the panels.

Two variations of hydraulic cooling were researched: …

Improving Pv Module Efficiency Through Cooling, Harrison Dawson

Chemical Engineering Undergraduate Honors Theses

The Solarbacks researched and designed a variety of cooling methods that could be used to improve the efficiency of photovoltaics. These cooling methods can be separated into two categories: active and passive methods. The active cooling method of hydraulic cooling and the passive cooling methods of heat sinks (fins), optical coatings, thermosyphons, phase change materials, and thermoelectric generators were all taken into consideration as potential cooling methods. Passive cooling methods were preferred because the use of electricity required for the cooling mechanism would reduce the net electricity and subsequent profit from the panels.

Two variations of hydraulic cooling were researched: …

Machine Learning Modeling Of Horizontal Photovoltaics Using Weather And Location Data, Christil Pasion, Torrey J. Wagner, Clay Koschnick, Steven J. Schuldt, Jada B. Williams, Kevin Hallinan

Faculty Publications

Solar energy is a key renewable energy source; however, its intermittent nature and potential for use in distributed systems make power prediction an important aspect of grid integration. This research analyzed a variety of machine learning techniques to predict power output for horizontal solar panels using 14 months of data collected from 12 northern-hemisphere locations. We performed our data collection and analysis in the absence of irradiation data—an approach not commonly found in prior literature. Using latitude, month, hour, ambient temperature, pressure, humidity, wind speed, and cloud ceiling as independent variables, a distributed random forest regression algorithm modeled the combined …

Data-Driven Modeling Through Power Hardware In The Loop Experiments: A Pv Micro-Inverter Example, Hayder Dawood Abbood Almukhtar

Theses and Dissertations

The increasing penetration of wind turbines, photovoltaics (PV), fuel cells, microturbines, cogeneration, energy storage systems, and other Distributed Energy Resources (DER) presents both challenges and opportunities for distribution systems. A deep understanding of the characteristics of those devices, as well as accurate modeling, are essential to plan, design, and control modern distribution grids.

The objective of this research is to define data-driven modeling techniques that allow capitalizing on the results of Hardware In the Loop (HIL) and Power Hardware In the Loop (PHIL) testing by creating models of the devices under test (DUT) –also for closed-source, proprietary systems– using the …

Golng Off The Grid: Optimizing Solar Renewable Energy Systems At Remote Locations To Minimize Logistics Requirements, Increase Sustainability, And Strengthen Energy Assurance, Nathanael J. Thomsen

Theses and Dissertations

Grid-based electrical infrastructure is unavailable at many remote locations including developing nation communities, isolated construction sites, and military contingency bases. Powering these locations with diesel generators requires regular fuel resupply, resulting in increased costs, environmental impacts, and burdensome logistics—making generators an obstacle for energy resiliency and sustainability. This research examines using solar renewable energy systems to replace generators at remote locations and presents a multi-objective optimization model that minimizes logistics variables. Replacing a single deployed generator would save over 500,000 gal of fuel annually, eliminating the need for 100 fuel tanker deliveries.

Tailoring The Grain Boundaries Of Wide-Bandgap Perovskite Solar Cells By Molecular Engineering, Khalid Emshadi

Electronic Theses and Dissertations

Due to the attraction of fabricating highly efficient tandem solar cells, wide-bandgap perovskite solar cells have attracted substantial interest in recent years. However, polycrystalline perovskite thin-films show the existence of trap states at grain boundaries, which diminish the optoelectronic properties of the perovskite and thus remains a challenge. This research demonstrates a one-step solution-processing of the [MA_0.9Cs_0.1Pb(I_0.6Br_0.4)3] wide-bandgap perovskite using Phenylhydrazine Iodide with amino groups to successfully passivate the trap density within grain boundaries and increase the perovskite grain size. The reinforced morphology and grain boundaries treatment considerably enhanced the photovoltaic performance …

Photovoltage Enhancement For Stable Perovskite Solar Cells With A Temperature-Controlled Grain Growth Technique, Luis Eduardo Valerio

Open Access Theses & Dissertations

By performing strong characterizations methods, one can begin to fully understand the chemistry and composition behind a great performing perovskite solar cell. Understanding how the interaction between layers inside a solar cell is driven by the temperature and overall environment is a key element to improve the fabrication process and overall efficiency of such cells. This Thesis will present a study of the hybrid organic-inorganic, mixed-cation, mixed-halide, temperature and thickness-controlled perovskite solar cell. A constant power conversion efficiency (PCE) ranging between 15-17% and an open circuit voltage V¬oc above 1.05 V for a wide-band gap perovskite cell is presented.