MS, University of Cincinnati, 2013, Engineering and Applied Science: Civil Engineering

The interest in renewable energy has been increasing in recent years as attempts to reduce energy costs as well the consumption of fossil fuels are becoming more common. Companies and organizations are recognizing the increasing reliance on limited fossil fuels' resources, and as competition and costs for these resources grow, alternative solutions are becoming more appealing. Many federally run buildings and associations also have the added pressure of meeting the mandates of federal energy policies that dictate specific savings or reductions. Federal highway maintenance facilities run by the Department of Transportation fall into this category. To help meet energy saving goals, an investigation into potential renewable energy technologies was completed for the Ohio Department of Transportation. This research examined several types of renewable energy technologies and the major factors that affect their performance and evaluated their potential for implementation at highway maintenance facilities. Facilities energy usage data were provided, and a facility survey and site visits were completed to enhance the evaluation of technologies and the suitability for specific projects. Findings and technology recommendations were presented in the form of selection matrices, which were designed to help make selections in future projects. The benefits of utilization of other tools such as analysis software and life cycle assessments were also highlighted. These selection tools were designed to be helpful guides when beginning the pursuit of a renewable energy technology for highway maintenance facilities, and can be applied to other similar building types and projects. This document further discusses the research strategies and findings as well as the recommendations that were made to the personnel overseeing Ohio's highway maintenance facilities.

Committee: Hazem Elzarka Ph.D. (Committee Chair); Shaaban Abdallah Ph.D. (Committee Member); Ahmed Elgafy Ph.D. (Committee Member); Heng Wei Ph.D. (Committee Member) Subjects: Civil Engineering

Doctor of Philosophy, The Ohio State University, 2022, Electrical and Computer Engineering

Due to the increased penetration of inverter-based resources (IBRs) in bulk power system (BPS) networks, to conduct interconnection studies, generic dynamic mod- els of the second-generation renewable energy system models were developed by the Western Electricity Coordinating Council (WECC) Renewable Energy Modeling Task Force. The dynamic models have been extensively implemented in various power system simulation software packages, and the block diagram representation of the dynamic models is widely present in various technical reports and literature. However, there is a gap between the mathematical model and knowledge of key parameters for the second-generation renewable energy system dynamic models. The complex nonlinear nature of the dynamic models makes it highly challenging for the transmission planning engineers to identify the key parameters when the IBRs are subjected to large-scale voltage and frequency disturbances. This is needed to ensure grid stability under contingencies. For instance, the Type 3 wind turbine generator (WTG-3) model consists of 7 modules with 118 user-defined parameters, interfaced through 26 states and 9 control flags to facilitate the plant operation in different control modes. Thus, this work presents a methodology for the key parameter identification in non- linear models of power systems. The proposed methodology is applied to identify the key parameters of the transmission-scale IBRs (solar PV power plants, wind power plants, and battery energy storage system plants) dynamic models using proposed global sensitivity analysis techniques. It fills up the gap regarding the requirement of the mathematical model and knowledge of key parameters. In contrast to the state-of-the-art methods, the proposed modified Morris, modified Sobol', and modified eFAST sensitivity analysis techniques do not linearize the dynamic models of IBRs around an operating point, providing critical insights into the large-signal stability analysis. The (open full item for complete abstract)

Committee: Mahesh Illindala Dr. (Advisor); Xin Feng Dr. (Committee Member); Jin Wang Dr. (Committee Member); Antonio Conejo Dr. (Committee Member) Subjects: Electrical Engineering; Energy

Master of Science (MS), Ohio University, 2021, Geography (Arts and Sciences)

Issues of greenhouse gas emissions and climate change are shaping the energy policies of various nations. Embracing low carbon technologies whiles incrementally reducing dependence on fossil fuel technologies seems to be the world's direction on energy at the moment. This study investigates how the energy policy of Ohio is promoting, if at all, this larger transition away from fossil fuels. The study made use of both primary and secondary data. The primary data was generated from responses through a semi-structured interview protocol from experienced professionals working within and outside the energy industry of Ohio. Secondary data was gotten from published academic and journalistic articles and then the use of document analysis was used to analyze them. There was a combined use of both textual and content analysis on secondary data obtained for this research. The study revealed that even though Ohio has a good ranking on its net metering policy, a holistic view of the energy policy thwarts Renewable Energy development. As it stands, the Renewable Wind Industry is stalled in development due to current policies. Also, various attempts by the legislature to introduce bills that do not promote renewables scare would-be investors. Ohio's current energy policy favors fossil fuels and nuclear plants. Lastly, stakeholders with an interest in Renewable Energy development have insufficient power to see it through the Ohio legislature. In light of this, the study proposes the way forward for a smooth transition from fossil fuel plants to renewables by calling for federal intervention in setting standards and providing the way forward for the cleaning of the electricity grid of Ohio.

Committee: Harold Perkins (Committee Chair); Geoffrey Buckley (Committee Member); Risa Whitson (Committee Member) Subjects: Climate Change; Energy; Environmental Justice; Geography; Political Science; Public Policy; Regional Studies

Doctor of Philosophy (Ph.D.), University of Dayton, 2019, Electrical and Computer Engineering

Electric power grids are currently undergoing a major transition from large centralized power stations to distributed generation in which small and flexible facilities produce power closer to where it is needed. This move towards a decentralized delivery of energy is driven by a combination of economic, technological and environmental factors. In recent years, the cost of renewable energy in the form wind turbines and solar PV has dropped dramatically due to advances in manufacturing and material science, leading to their rapid deployment across the US. To supplement the intermittent nature of wind and solar energy, there is a growing need for small, highly controllable sources such as natural gas turbines. With the fracking boom in the US, there is currently abundant natural gas to use for this purpose. The resulting proliferation of many small energy producers creates technical problems such as voltage and frequency control that can be addressed with battery storage, whose cost is also dropping. These factors are leading to a move away from large energy production facilities that require too much initial investment. Also, a distributed supply is more efficient and reliable. The threat of global climate change is creating pressure to increase the integration of distributed generation and information technology is now capable of managing a greater number of energy producers, utilizing a vast supply of information to predict supplies and demand and to determine optimal dispatching of energy. The move towards a higher percentage of renewable energy creates many interesting technical issues, many of which are due to the lack of control over the renewable resources. Energy dispatching between multiple sources, some controllable and some not, and multiple loads leads to a need for dispatching strategies that maximize the percentage of the load that is met with renewable energy. A growing aspect of this energy dispatch is a stream of information about energy demand, w (open full item for complete abstract)

Committee: Malcolm Daniels Dr. (Advisor) Subjects: Electrical Engineering; Energy; Mechanical Engineering

Master of Science, The Ohio State University, 2020, Environment and Natural Resources

Community solar projects allow users to take ownership in the energy they consume. With several such projects emerging rapidly all around the world, within United States and in the state of Ohio, very little is known today regarding the development and community acceptance of these projects. In this scenario, this exploratory research investigates the different reasons as to why a community adopts such renewable energy systems in order to clarify our understanding of the diffusion process. This rapid diffusion of community solar projects in Ohio is examined through the lens of diffusion of innovation (DOI) theory put forward by E. Rogers (1962), which states that the adoption of an innovation is dependent on factors like the characteristics of potential adopters, the attributes of the innovation itself and as well as the setting where the diffusion takes place. The research involves in-depth interviews with key informants, starting with the current managers of municipally owned/utility-owned solar projects, representatives from area businesses, industry, and community groups in three study sites located within Ohio. The interviews seek to capture the development (process) of three community solar initiatives: the local decision-making process for the projects, project features, types of impacts perceived to have occurred in local communities due to these projects and their future. My findings from this exploratory research suggests that it is indeed the local context of these communities that drives the groundwork and development of such renewable energy initiatives, with each of the three study sites having a distinct premise, along with the provision of an incentive program or a policy enacted at either state or federal level (or both), contributing towards the establishment of these solar facilities. Moreover, the findings also suggest that it is the economic benefits of these projects, combined with their relative unobtrusiveness, that ultimately determin (open full item for complete abstract)

Committee: Jeffrey Jacquet (Advisor) Subjects: Environmental Studies

BA, Oberlin College, 2012, Environmental Studies

I performed quantitative analyses and qualitative interpretation of energy policy data, energy production and consumption data, and political data. I collected data on state Renewable Portfolio Standards from the Database for State Incentives for Renewable Energy (DSIRE), energy production and consumption data for the 50 states and Washington D.C. from the Energy Information Agency (EIA), and 1992 presidential election data from the internet. I identify relationships that exist between these different types of variables, and where Ohio fits in the national context of existing energy patterns and policies. There are several conclusions found in the literature that are independently tested with the data I have collected. I hypothesize that enactment of Renewable Portfolio Standard (RPS) policies and geographic location in the United States are not robust indicators of the proportion of energy generation in states that comes from renewable sources, and that the strength of RPS policies is not based upon location (Carley 2009). Furthermore, I predict that states that are politically left leaning have larger proportions of their energy generation coming from renewable sources and have stronger RPS policies (Carley 2009). Finally, I postulate that Ohio's energy policy will be weaker relative to some policies based upon descriptive statistics of the RPS policies. Tests utilized include correlations, T-tests, and multiple linear regressions for geographic variables. I also performed a spatial analysis of renewable energy potential and unemployment rates in the state of Ohio. I found National Renewable Energy Laboratory maps of average wind speed, solar radiation, biomass yield, and a Bureau of Labor Statistics map of unemployment rates at the county level. I calculated correlation coefficients between unemployment rate and renewable resource abundance according to a 24-section grid I overlaid on the state. No positive statistically significant results occurred, with the h (open full item for complete abstract)

Committee: Jordan Suter PhD (Advisor); Harlan Wilson PhD (Committee Chair); John Petersen PhD (Committee Member) Subjects: Environmental Studies

Master of Science in Renewable and Clean Energy Engineering (MSRCE), Wright State University, 2023, Renewable and Clean Energy

In the past several years, the energy sector has experienced a rapid increase in renewable energy installations due to declining capital costs for wind turbines, solar panels, and batteries. Wind and solar electricity generation are intermittent in nature which must be considered in an economic analysis if a fair comparison is to be made between electricity supplied from renewables and electricity purchased from the grid. Energy storage reduces curtailment of wind and solar and minimizes electricity purchases from the grid by storing excess electricity and deploying the energy at times when demand exceeds the renewable energy supply. The objective of this work is to study the generation of electric power with wind turbines and solar panels coupled to either battery energy storage or hydrogen energy storage. So that logical conclusions can be drawn on the economic effectiveness of battery and hydrogen energy storage, four scenarios are analyzed: 1) purchasing all required electricity from the grid, 2) generating electricity with a combined wind and solar farm without energy storage, 3) generating electricity with a combined wind and solar farm with battery energy storage, and 4) generating electricity with a combined wind and solar farm with hydrogen energy storage. All four of these scenarios purchase electricity from the grid to meet demand that is not met by the renewable energy power plant. All scenarios are compared based on the lowest net present cost of supplying the specified electrical loads to serve 25,000 homes in Rio Vista, California over 25 years of operation. The detailed economics and electric power production of both wind and solar combined with energy storage for any size of wind facility, solar facility, battery facility, and hydrogen facility are analyzed with a MATLAB computer program developed for this work. The program contains technical and economic models of each of these systems working in different combinations. Current equipment c (open full item for complete abstract)

Committee: James Menart Ph.D. (Advisor); Hong Huang Ph.D. (Committee Member); Mitch Wolff Ph.D. (Committee Member) Subjects: Alternative Energy; Energy; Engineering

Doctor of Philosophy (Ph.D.), University of Dayton, 2023, Electrical Engineering

Lithium-ion batteries (LIBs) have transformed modern electronics and rapidly advancing electric vehicles (EVs) due to high energy, power, cycle-life, and acceptable safety. However, the comprehensive commercialization of EVs necessitates the invention of LIBs with much enhanced and stable electrochemical performances, including higher energy/power density, cycle-life, and operation safety but at a lower cost. An unprotected lithium-ion battery (LIB) cell cathode using lithium metal anode and organic carbonate liquid electrolyte undergoes significant structural damage during the cycling (Li+ intercalation/ deintercalation) process. Also, a bare cathode in contact with a liquid electrolyte forms a resistive cathode electrolyte interface (CEI) layer. Both the cathode structure damage and CEI lead to rapid capacity fade. Different strategies have been used to mitigate the degradation of LIB electrodes, including designing electrolytes to enhance SEI/CEI formation, cycle stability, interface engineering with protective coatings to prevent the breakdown of active material particles during cycling, composition control of the electrode particles, synthetic optimization to control particle morphology, the use of composites made from conductive scaffolds and active materials and designing new electrode architectures to overcome volume changes and enhance transport properties. Cathode surface modification has been used to reduce CEI formation and structural damage, improving capacity retention, cycle life, energy density, power density, and safety of a LIB. Recently, the coating of the cathode with an intermediate layer (IL), which is transparent to Li+ conduction but impermeable to electrolyte solvent, has been developed to minimize CEI formation and structural damage. IL based on Li+ insulating ceramics, such as aluminum oxide (Al2O3), tin oxide (SnO2), and magnesium oxide (MgO), has been developed but to limited success in mitigating the above cathode degradation. The (open full item for complete abstract)

Committee: Dr. Jitendra Kumar (Committee Chair); Dr. Guru Subramanyam (Committee Member); Dr. Feng Ye (Committee Member); Dr. Vikram Kuppa (Committee Member) Subjects: Electrical Engineering; Energy; Engineering

Master of Science, The Ohio State University, 2022, Environmental Science

US policymakers at the local, state, and federal levels are considering policy mechanisms to promote renewable energy development and ensure a just transition to a clean energy infrastructure. These policies have the potential to both reduce greenhouse gas emissions and create jobs; however, the number of actual jobs created from these policy instruments is often disputed. In this study, I evaluate the direct non-hydroelectric renewable energy employment impacts from eight types of renewable energy policies: (1) subsidy programs; (2) corporate, (3) personal, and (4) other tax incentives; (5) performance-based incentives; (6) industry recruitment/support; (7) renewable portfolio standards; and (8) net metering. Using data from 3,035 US counties from 2001 to 2017, I employ Fixed Effects (FE) regression models controlling for calculated propensity scores, which address the potential selection bias in the model. The results indicate that three of the policy instruments (renewable portfolio standards, industry recruitment/support, and performance-based incentives) have positive and statistically significant impacts on direct non-hydro renewable energy employment at the county level. The policy type with the greatest positive impact was industry recruitment/support. Counties with industry recruitment/support policies present, on average, had 82 more direct non-hydro renewable energy jobs than counties that did not have industry recruitment/support present, holding all else constant. Critically, the results show the importance of addressing selection bias in analyses of renewable energy policy outcomes, as the models run without controlling for propensity scores led to an overestimation of employment impacts.

Committee: Dr. Daniel Gingerich (Advisor); Dr. Jeff Bielicki (Committee Member); Dr. Rob Greenbaum (Committee Member) Subjects: Energy; Public Policy; Sustainability

Master of Sciences, Case Western Reserve University, 2022, Physics

The increasing adoption of renewable sources of electricity (i.e. wind and solar farms) is being driven by the demand for carbon neutral electricity production. Although zero carbon is emitted during electricity production, these renewable energy sources suffer from intermittency, which is a mismatch between the supply and demand of electricity of the grid. Renewable energy sources, such as wind and solar, produce their peak electricity at off-demand periods of the day. This strains the electrical grid as it risks over-generation in some locations as well as a need for quick ramping of the electrical load which is hard on electricity producing infrastructure. As a partial solution to intermittency, pumped storage hydropower (PSH) is the dominant form of grid-scale energy storage. PSH accounts for 95% of the U.S. grid-scale storage capacity, which amounts to 22.9 GW of capacity [1]. The EIA also estimates with all possible sites, the U.S. can double their PSH capacity [1]. However, much more than that is not feasible being constrained by the availability of locations suitable for PSH. As a result, other gridscale energy storage options are in development. The main options include batteries, thermal energy storage, compressed air energy storage (CAES) and flywheels. However, these storage options are plagued by high cost per kWh prices, location specificity (ex. PSH, CAES) and/or low energy density. With these concerns in mind, Cratus LLC is developing a molten salt thermal energy storage option known as ThermaBlox, which is location-independent, low-cost, and high-capacity (with the capability to scale). ThermaBlox will play a significant role in intermittency reduction while enabling increased adoption rates of renewable energy.

Committee: Edward Caner (Committee Chair); Dr. Benjamin Monreal (Committee Member); Dr. Robert Brown (Committee Member) Subjects: Chemical Engineering; Energy; Engineering; Entrepreneurship; Fluid Dynamics; Mathematics; Nanotechnology; Physics; Technology

Doctor of Philosophy, The Ohio State University, 2022, Chemistry

Increasing concerns about carbon emissions has led to the global adoption of renewable energy initiatives. Direct integration of renewable energy sources, however, is difficult because of the intermittency of such sources. Furthermore, direct integration would overload the grid and lead to blackouts. Thus, grid-scale electrical energy storage is required to store and provide energy on-demand. Redox flow batteries have attracted attention as a scalable, inexpensive storage technology. Flow batteries store energy in solvated, redox-active electrolytes, as opposed to conductive, solid materials. These solutions are stored in separated reservoirs and are flowed to the electrochemical cell to cycle the redox-active compound. Energy stored in this fashion decouples energy and power, which allow for increased operational control. While many electrolytes exist, few electrolyte examples have achieved commercialization because of low solubility and low cell voltage. Redox-targeting flow batteries have emerged as an improvement to classic flow technology. Rather than storing energy in solution, redox -targeting flow batteries store energy in an insoluble solid while a solubilized electrolyte serves to shuttle electrons from the electrochemical cell to the solid. This strategy serves to combine the high energy density of solid-state batteries and scalability of flow batteries. Current redox targeting technology is mainly limited to the use of inorganic solid materials. These materials are cycle by an intercalation mechanism, which requires low current densities that lead to long cycle times. Furthermore, pairing shuttles with these materials are difficult because of distinct redox potentials and electron transfer rates of these solids. Our efforts focused on the development of an all-organic redox targeting flow battery. Organic materials generally do not operate based on intercalation mechanisms and the synthetic flexibility of organic compounds allow for the fin (open full item for complete abstract)

Committee: Christo Sevov (Advisor); Yiying Wu (Committee Member); Jovica Badjic (Committee Member) Subjects: Chemistry; Energy

Master of Arts (MA), Ohio University, 2022, Geography (Arts and Sciences)

Environmental issues such as habitat destruction, pollution, and climate change have spurred societies around the world to invest in new forms of alternative energy to reduce dependency on fossil fuels and the impacts that result from their extraction and use. The United States is the largest economy on Earth and consumes the most fossil fuels per capita. In this regard, the U.S. is lagging behind in terms of developing and utilizing alternative energy, but it is not the case that alternatives beyond fossil fuels are not being utilized at all. In fact, one of the biggest alternative energy booms in the U.S. has developed around wind energy. At the same time, the fossil fuel industry has undergone massive changes, shifting to natural gas while phasing out the use of coal. The state of Iowa has been a leader in developing and utilizing wind power for more than a decade, and in combination with utilizing more natural gas, has phased out using coal as a primary source for generating electricity. Like Iowa, Ohio has been replacing coal with natural gas in recent years, but unlike the Hawkeye State, has largely shunned wind power. Both states have gone in opposite directions in terms of electricity generation, but both have reduced their carbon footprint by very large amounts. In this thesis, I compare and contrast Iowa and Ohio

Committee: Geoffrey Buckley (Committee Chair); Ana Myers (Committee Member); Timothy Anderson (Committee Member) Subjects: Energy; Environmental Economics; Environmental Geology; Environmental Science; Environmental Studies; Geography; Geology; Land Use Planning; Natural Resource Management

PHD, Kent State University, 2021, College of Arts and Sciences / Department of English

Ethnographic UX research applied to technical communication about a large scale sustainable energy project shows that an embodied understanding of the environment prevails in the public, pointing toward more effective methods for communicating scientific and policy information through improved use of metaphor in technical communication.

Committee: Pamela Takayoshi (Advisor); Brian Huot (Committee Member); Derek Van Ittersum (Committee Member); Joseph Ortiz (Committee Member); Eren Metin (Other) Subjects: Alternative Energy; Climate Change; Cognitive Psychology; Communication; Composition; Ecology; Education; Energy; Environmental Education; Linguistics; Literacy; Logic; Public Policy; Rhetoric; Technical Communication

Master of Science in Chemistry, Youngstown State University, 2021, Department of Biological Sciences and Chemistry

The semiconductor cadmium telluride (CdTe) has become the leading material for thin-film photovoltaic applications. Among the many techniques for preparing these thin films, electroless deposition, commonly known as chemical bath deposition, deserves special focus since it has been shown to be a pollution-free, low-temperature and inexpensive method. In this project, CdTe thin films were deposited on stainless steel 304 by the electroless deposition method using cadmium acetate and tellurium oxide dissolved in pH 12.5 NH3(aq). The deposition was based on the gradual release of cadmium ions (Cd2+) and the gradual addition of tellurium as TeO3 2- and their subsequent reduction in a hot aqueous alkaline chemical bath at 70 °C. This was attained by adding a complexing agent such as ammonia and a chemical reducing agent. Using triethanolamine as a complexing agent produced similar results. The following reducing agents were used: aluminum, sodium hypophosphite, formaldehyde, sodium borohydride and hydrazine. All of them deposited a film on stainless steel containing Cd and Te, but formaldehyde produced the best films in terms of uniform thickness, photosensitivity, and rapid growth rate. Electroless deposition of a thin Pt layer on top of the CdTe film improved the cathodic CdTe polarization for hydrogen evolution. The structural and morphological properties of the resulting films were characterized using X-ray diffraction (XRD), stylus profilometry, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) while the light/dark voltametric methods were used to determine the films' photosensitivity.

Committee: Clovis Linkous PhD (Advisor); Timothy Wagner PhD (Committee Member); Christopher Arnsten PhD (Committee Member) Subjects: Chemistry; Energy; Experiments; Materials Science

Doctor of Philosophy, The Ohio State University, 2020, Environment and Natural Resources

The ongoing shale energy revolution has transformed global energy markets and positioned the United States as a leader in oil and natural gas production and exports for the first time in generations. However, little scholarly attention has been directed toward the downstream impacts of these developments on the people and places which experience energy export activity or host related infrastructure, particularly those in rail export corridors. This research presents a first-of-its kind, cross-regional comparative analysis of community risks, risk perceptions, energy and environmental attitudes, and related discourses in oil train export corridor communities. The mixed-methods design uses household-level survey data (N=571), interview data (N=58), and news media content analysis data (N=149), to address three key knowledge gaps regarding impacts of and attitudes toward crude oil by rail in examining: 1) the influences and distributions of support, opposition, and increased concern to oil by rail; 2) views toward hydrocarbon exports as well as broader energy preferences; and 3) dominant news media and stakeholder discourses and discursive channels concerning oil train activity. Results and related recommendations include the identification of community risk perceptions, vulnerabilities, and broader energy and export attitudes as well as predictors of their variation; discussion of implications for related community energy siting and planning, news media reporting, and communications; and the contribution of novel baseline data vis-a-vis predictors of risk perception and opposition concerning oil train activity and infrastructure to the risk perception and energy impacts fields.

Committee: Jeffrey Jacquet PhD (Advisor); Kerry Ard PhD (Committee Member); Jeffrey Bielicki PhD (Committee Member); Robyn Wilson PhD (Committee Member) Subjects: Area Planning and Development; Energy; Environmental Science; Social Psychology; Sociology

Doctor of Philosophy, The Ohio State University, 2019, Environmental Science

Reducing carbon dioxide (CO2) emissions is one of the most pressing issues facing the electricity system. Towards this end, prior work investigated generating electricity with geologically stored CO2 by using it to extract heat from sedimentary basins geothermal resources. This dissertation expands on this idea by developing and valuing approaches for CO2-based energy storage. In the first chapter, we investigate the value that three bulk energy storage (BES) approaches have for reducing system-wide CO2 emissions and water requirements: CO2-Bulk Energy Storage (CO2-BES), which is a CO2-based energy storage approach that uses a concentric-ring, pressure based (CRP-BES) design, Pumped Hydro Energy Storage (PHES), and Compressed Air Energy Storage (CAES). Our results suggest that BES could decrease system-wide CO2 emissions by increasing the utilization of wind, but it can also alter the dispatch order of regional electricity systems in other ways (e.g., increase in the utilization of natural gas power capacity and of coal power capacity, decrease in the utilization of nuclear power capacity). While some changes provide negative value (e.g., decrease in nuclear increased CO2 emission), the system-wide values can be greater than operating cost of BES. In the second and third chapters, we investigate two mechanisms for using CO2 for energy storage: storage of (1) pressure and (2) heat. For pressure storage, we investigated the efficacy of the CO2-BES system using the CRP-BES design over cycles of varying durations. We found that CO2-BES could time-shift up to a couple weeks of electricity, but the system cannot frequently dispatch electricity for longer durations than was stored. Also, the cycle duration does not substantially affect the power storage capacity and power output capacity if the total time spent charging, discharging, or idling is equal over a multi-year period. For thermal energy storage, we investigated the efficacy of using pre-heated CO2 and pre-h (open full item for complete abstract)

Committee: Jeffrey Bielicki (Advisor); Ramteen Sioshansi (Committee Member); Gil Bohrer (Committee Member); Brent Sohngen (Committee Member) Subjects: Alternative Energy; Energy; Engineering; Environmental Economics; Environmental Science

Master of Science (M.S.), University of Dayton, 2018, Renewable and Clean Energy

The off-grid location and unreliable electricity supply to medical clinics in remote parts of India make it difficult to safely store vaccines and other medications using traditional refrigeration systems. The Engineers in Technical Humanitarian Opportunities of Service-learning (ETHOS) program at the University of Dayton, in collaboration with Solar Alternative and Associated Programmes (SAAP) of Patna India, are developing a novel refrigeration system which works on the principle of solar thermal adsorption. This refrigeration system does not require electricity for operation and uses safe, environmentally benign and locally available adsorption pair of ethanol-activated carbon. A bench -scale prototype was developed at the University of Dayton using ethanol-activated carbon as working pair which can generate evaporative temperatures between 2°C and 8°C. The existing horizontally oriented system can achieve targeted refrigeration temperatures (2 - 8°C) during the adsorption cycle and ethanol can be desorbed from the activated carbon during desorption. However, the horizontal geometry inhibited the return of liquid ethanol to the evaporation chamber. A new vertical oriented bench scale system was built to addresses the limitation of the original prototype. The effects of desorption heating temperature, desorption time duration, double activation of activated carbon on evaporative cooling, and possible decomposition of ethanol during desorption were analyzed. Experimental results suggested better desorption happens at elevated temperature (90-125°C) and most of the desorption happens in the first 1-2 hours of heating the adsorbent bed. The high pressure on the evaporator side for multiple adsorption-desorption process, and analysis of GC/MS of desorbed ethanol obtained from the analytical chemist showed possible decomposition of ethanol. The ethanol decomposition prevented multiple cycle operation of the system. The use of double activation techn (open full item for complete abstract)

Committee: Amy Ciric Ph.D. (Committee Chair); Jun Ki Choi Ph.D. (Committee Chair); Li Cao Ph.D. (Committee Member) Subjects: Alternative Energy; Chemical Engineering; Chemistry; Climate Change; Energy; Engineering; Environmental Science; Experiments; Materials Science; Mechanical Engineering

MS, University of Cincinnati, 2017, Engineering and Applied Science: Aerospace Engineering

A conceptual energy ship is presented to provide renewable energy. The ship, driven by the wind, drags a hydrokinetic turbine through the water. The power generated is used to run electrolysis on board, taking the resultant hydrogen back to shore to be used as an energy source. The basin efficiency (Power/thrust*velocity) of the Hydrokinetic Turbine (HTK) plays a vital role in this process. In order to extract the maximum allowable power from the flow, the blades need to be optimized. The structural analysis of the blade is important, as the blade will undergo high pressure loads from the water. A procedure for analysis of a preliminary Hydrokinetic Turbine blade design is developed. The blade was designed by a non-optimized Blade Element Momentum Theory (BEMT) code. Six simulations were run, with varying mesh resolution, turbulence models, and flow region size. The procedure was developed that provides detailed explanation for the entire process, from geometry and mesh generation to post-processing analysis tools. The efficiency results from the simulations are used to study the mesh resolution, flow region size, and turbulence models. The results are compared to the BEMT model design targets. Static pressure maps are created that can be used for structural analysis of the blades.

Committee: Mark Turner Sc.D. (Committee Chair); Shaaban Abdallah Ph.D. (Committee Member); Clarissa Belloni Ph.D. (Committee Member) Subjects: Aerospace Materials

Doctor of Philosophy, University of Toledo, 2017, Mechanical Engineering

This dissertation proposes a multi-level optimization method for slender structures such as blades or towers of wind turbine structures. This method is suited performing structural optimizations of slender structures with a large number of design variables (DVs). The proposed method uses a two-level optimization process: a high-level for a global optimization of a structure and a low-level for optimizations of sectioned computational stations of the structure. The high-level optimization uses approximating functions to define target structural properties along the length of a structure, such as stiffness. The approximating functions are functions of the distance from the root of the structure that are defined using basis functions such as polynomials or exponential functions. The high-level DVs are the coefficients of the functions. Thus, the number of the high-level DVs is independent of the number of sections. Moreover, selecting smooth approximating functions help to obtain alternative designs with smooth shapes. The low-level optimization finds an optimum parametric design, such as laminate layups, that matches with the target structural properties defined at the high-level optimization. At the low-level optimization, the proposed method uses an optimizer in each section. Each optimizer is independent of the optimizers in the other sections, thereby decomposing a large optimization problem into several small ones. This approach reduces the number of DVs per optimizer at the low-level optimization which reduces the design space of each section and eliminates the design space of coupling between sections. Once optimum designs are found from all sections at the low-level, the high-level solvers evaluate them for the entire structure. The advantage of the proposed method is that it reduces the number of iterations of the high-level optimization because it considers a small number of high-level DVs. Computational efficiency increases because the computationally e (open full item for complete abstract)

Committee: Efstratios Nikolaidis Ph.D. (Committee Chair); Vijay Devabhaktuni Ph.D. (Committee Co-Chair); Abdollah Afjeh Ph.D. (Committee Co-Chair); Sorin Cioc Ph.D. (Committee Member); Douglas Nims Ph.D. (Committee Member); Larry Viterna Ph.D. (Committee Member) Subjects: Aerospace Engineering; Energy; Engineering; Environmental Economics; Environmental Engineering; Mechanical Engineering; Operations Research

Master of Science in Engineering, University of Akron, 2017, Electrical Engineering

In recent years, the Microgrid (MG), a widely acceptable small-scale power infrastructure, is being well developed due to its two characteristics. The rst is its ability to integrate distributed energy resources (DER), especially renewable energy sources (RES). The second is its resilience and reliability especially during emergent situations such as blackouts. Two important aspects for Microgrid Networks (MGN) are efficient coordination with other supportive MGs, which is achieved via energy trading, and security. This thesis proposes several mechanisms for energy trading in the MGN. Firstly, we propose a self-healing resilient Microgrid social network, in which the Deep Belief Network (DBN) algorithm is developed to predict the social relations between different energy users and producers and a coalition game model is designed to reduce the power loss in energy transmission. Secondly, we propose an energy trading mechanism using the game theoretic method by considering the non-stability of renewable energy sources (RES) and social network, by which the individual's decision-making is influenced. Finally, this thesis proposes a Bayesian game-based energy trading mechanism, in which the market participants can share partial information with others to preserve their privacy. The work in this thesis paves the way for further investigation and realization of resilient reliable Microgrids (MGs) to improve reliability and quality of the power supply.

Committee: Jin Wei (Advisor); Hamid Bahrami (Committee Member); Shiva Sastry (Committee Member) Subjects: Electrical Engineering; Energy