Theses and Dissertations at Montana State University (MSU)

Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733

Browse

Search Results

Now showing 1 - 10 of 15

Impacts of species protections on wind turbine development: evidence from golden eagle protection policies
(Montana State University - Bozeman, College of Agriculture, 2023) O'Brien, Brock Daniel; Chairperson, Graduate Committee: Diane Charlton
As demand for wind energy grows, policymakers face tradeoffs between wind turbine development and wildlife species protections. This is particularly relevant for golden eagles, which have a habitat that overlaps areas of high wind energy development potential. Golden eagle protections, such as the Bald and Golden Eagle Protection Act (BGEPA), therefore potentially conflict with wind energy development goals. Policymakers face a lack of information regarding the existence and size of potential impacts of species protections on wind development. To approach this issue, I employ a difference-in-differences research design exploiting variation in BGEPA enforcement over time and geographic variation in golden eagle exposure to identify the impacts of species protections on wind development in resource-rich areas. I find that counties with high golden eagle exposure experienced declines in expected wind turbine capacity additions of 3.78 megawatts during the enforcement period, suggesting a total of 420 megawatts of foregone wind energy. This electricity generation loss has an estimated value of $56 to $142 million annually. Existing golden eagle valuation methods suggest significant economic gains from wind turbine expansion, although these estimations arguably apply only to marginal wildlife impacts and should be applied with caution. These results emphasize that the value of foregone renewable energy is an often-overlooked component of species protection policy discussions, and that effective conservation measures and funding are necessary both for the futures of many species and for renewable technology deployment.
The impact of including a renewable energy theme on physics education and perception of meaning
(Montana State University - Bozeman, College of Letters & Science, 2021) Kahan, Adam; Chairperson, Graduate Committee: Greg Francis
A renewable energy theme was incorporated into an AP Physics class. Renewable energy linked assignments, articles, videos, and discussion developed the theme. The Force Concept Inventory and class exams tracked progress in physics. Surveys and interviews gathered data on perception of meaning. The results suggest that the theme neither facilitated nor interfered with the learning of physics. Learning physics, however, improved their understanding of renewable energy topics. Overall students found the theme meaningful and relevant.
Thermal energy storage with sensible heat in an air-alumina packed bed using axial flow, axial flow with layers and radial flow
(Montana State University - Bozeman, College of Engineering, 2020) Al-Azawii, Mohammad Mahdie Saleh; Chairperson, Graduate Committee: Ryan Anderson; Carter Theade, Megan Danczyk, Erick Johnson and Ryan Anderson were co-authors of the article, 'Experimental study on cyclic behavior of thermal energy storage in an air-alumina packed bed' published in the journal 'Journal of energy storage' which is contained within this dissertation.; Carter Theade, Pablo Bueno and Ryan Anderson were co-authors of the article, 'Experimental study of layered thermal energy storage in an air-alumina packed bed using axial pipe injections' in the journal 'Applied energy' which is contained within this dissertation.; Duncan Jacobsen, Pablo Bueno and Ryan Anderson were co-authors of the article, 'Experimental study of thermal behavior during charging in thermal energy storage packed bed using radial pipe' in the journal 'Applied thermal engineering' which is contained within this dissertation.
Thermal behavior in a packed bed thermal energy storage (TES) system is studied experimentally. TES systems are a promising solution to integrate renewable energy sources such as solar energy. The performance of such systems can be affected by different variables such as storage material size/type, pressure, temperature, heat transfer fluid (HTF), storage type (sensible/latent heat), and flow rate. Although these variables have been studied in literature, the resulting thermal dispersion and heat losses to the environment have been considered in few studies. This thesis studies the thermal behavior of an air-alumina TES packed bed focusing on dispersion and heat losses to quantify the thermal performance. Reducing their effects can improve the thermocline and thus thermal efficiency. The research efforts in this work quantify these effects and provide two new methods to reduce thermal dispersion and increase exergetic efficiency. Three configurations were considered in the present study. In the first configuration, a traditional packed bed is used focusing on performance for multiple partial cycles. This configuration quantified the thermal performance and served as a basis to compare the results from the other configurations. Dispersion effects were found to accumulate before a steady state was achieved during cycling. In the second and third configurations, novel pipe injection techniques were used to charge/discharge the bed. First, the normal bed is divided into layers via inserting pipes along the bed's axial length, focusing on a full charge-discharge cycle. Results show that exergy efficiency increases with flow rate and number of layers. The thermocline improved and dispersion losses decreased with number of layers. Second, a perforated pipe to facilitate radial flow was inserted at the center of the bed along the axial length to heat the bed. Radial charging shows higher charging efficiency compared to normal axial charging. Pipe injection is a novel method and a promising technique that improves the thermal performance of a lab scale storage bed, especially the layering method. Radial injection warrants more investigation to quantify its performance in thermal cycles.
Aluminate spinels for use as catalyst enhancement of solid oxide fuel cells
(Montana State University - Bozeman, College of Engineering, 2019) Zachariasen, Marley Sarria; Chairperson, Graduate Committee: Stephen W. Sofie
The growing necessity to find clean, efficient power sources has led to the advancement of technology in various fields of renewable energy. The field of electrochemical energy conversion, better known has Hydrogen Fuel Cell energy, has shown promise in replacing fossil fuels. This technology is fuel flexible, emits no harmful products, and generates power at efficiencies double or triple that of the Carnot combustion cycle widely used in automotive propulsion and large scale combustion power generation. However, the power production is limited by the short life expectancy of the components used to convert the chemical energy of the fuel into an electrical current. Two mechanisms work simultaneously during fuel cell operation to degrade the anodic electrode of the cell. The coarsening of the catalyst metal particles reduces the total active area of the anode while contaminants from the fuel deposit on the anodes remaining active areas, blocking fuel from the locations where the reaction takes place. Recent studies have shown that doping the industry standard fuel cell anode, Ni/YSZ, with a compound known as Aluminum Titanate (ALT) increases the overall resiliency of the cell. When heat-treated, ALT disassociates in to aluminum and titanium oxides which are then able to go into solution with the material components of the anode. These new secondary phases were shown to increase the strength and overall power output of the cell while decreasing the rate at which the catalyst coarsens. The electrochemical enhancements were attributed to the aluminum based secondary phase, known as nickel aluminate, a spinel structured compound which undergoes unusual reduction and catalytic transport kinetics. This work assesses the viability of transferring these enhancement effects to various other cermet anode systems by individually exchanging the ceramic ion conductor and metal electrocatalyst. The electrochemical performance and degradation, as well as mechanical properties, were evaluated for Ni/GDC anodes doped with ALT and alumina. In addition, synthesis and reduction behavior of cobalt and copper aluminate spinels were analyzed for similarities with nickel aluminate.
Excited state processes in ruthenium(II) polypyridyl complexes and cerium oxide nanoparticles
(Montana State University - Bozeman, College of Letters & Science, 2016) Stark, Charles William; Chairperson, Graduate Committee: Patrik R. Callis; Wolfgang J. Schreier, Janice Lucon, Ethan Edwards, Trevor Douglas and Bern Kohler were co-authors of the article, 'Interligand electron transfer in heteroleptic ruthenium(II) complexes occurs on multiple time scales' in the journal 'The journal of physical chemistry A ' which is contained within this thesis.
Solar driven hydrogen production from water is a sustainable alternative to fossil fuels, but suffers greatly from the large energy cost associated with splitting water. This report uses ultrafast transient absorption and other spectroscopic techniques to analyze several components that show potential for this photocatalysis, in particular observing the excited state dynamics of electron separation and recombination. In ruthenium(II) polypyridyl systems, the rate of interligand electron transfer (ILET) was found to change with time, initially behaving as an ultrafast barrierless process, but transforming into a much slower activated process as excess energy is vibrationally released over 100 ps following excitation. The change in ILET rates lead to changes in the population of localized 3 MLCT states distributed among each ligand, which are initially randomized, but favor the lower energy bipyridine ligands at longer times. Three analogous ruthenium complexes were then linked via a triazole bridge to a cobalt(II) polypyridyl center known to catalyze the formation of H 2, observing the electron transfer from ruthenium to cobalt using emission decay signals of the ruthenium complex. The electron transfer decay pathway was slower and relatively minor compared to similar ruthenium(II)-cobalt(II) systems; however, this reduced efficiency can potentially be explained by localizations on peripheral ligands, as well as a possible energy barrier on the 5-position of phenanthroline. Finally, citrate coated CeO 2 nanoparticles displayed ultrafast trapping of holes upon excitation with UV light, forming significantly deeper traps than has been observed in other metal oxides. Transient absorption signals of the excited holes decayed over hundreds of picoseconds, with lifetimes dependent on the pH of the solution, indicating that the trapping sites are influenced by the surface of the nanoparticle. The corresponding electrons appear to form long lived Ce 3+ sites, observable on timescales of minutes. The fate of these Ce 3+ sites is also pH dependent, indicating that CeO 2 may be an effective water-splitting photocatalyst under basic conditions.
Acoustic propagation modeling for marine hydrokinetic applications
(Montana State University - Bozeman, College of Engineering, 2016) Johnson, Charles Nathan; Chairperson, Graduate Committee: Erick Johnson
The combination of riverine, tidal, and wave energy have the potential to supply over one third of the United States' annual electricity demand [1]. However, in order to deploy and test prototypes and commercial installations, marine hydrokinetic (MHK) devices must meet strict regulatory guidelines. These regulations mandate the maximum amount of noise that can be generated and sets particular thresholds for determining disturbance and injury caused by noise. In the absence of measured levels from in-situ deployments, a model for predicting the propagation of a MHK source in a real hydroacoustic environment needs to be established. An accurate model for predicting the propagation of a MHK source(s) in a real-life hydro-acoustic environment has been established. This model will help promote the growth and viability of marine, water, and hydrokinetic energy by confidently assuring federal regulations are meet and harmful impacts to marine fish and wildlife are minimal. A 3D finite-difference solution to the governing velocity-pressure equations is presented and offers advantages over other acoustic propagation techniques for MHK applications as spatially varying sound speeds, bathymetry, and bed composition that form complex 3D interactions can be modeled. This solution method also allows for the inclusion of complex MHK sound spectra from turbines and/or arrays of turbines. A number of different cases for hydro-acoustic environments have been validated by both analytical and numerical results from canonical and benchmark problems. Several of these key validation cases are presented in order to show the applicability and viability of a finite difference numerical implementation code for predicting acoustic propagation in a hydro environment. With the model successfully validated for hydro-acoustic environments, more complex and realistic MHK sources from turbines and/or arrays can be modeled. A systematic investigation of MHK relevant scenarios is presented with increasing complexity including a single- and multi- source investigation, a random phase change study, and a hydro-acoustic model integration
Characterization of the [FeFe]-hydrogenase : toward understanding and implementing biohydrogen production
(Montana State University - Bozeman, College of Letters & Science, 2014) Swanson, Kevin Daniel; Chairperson, Graduate Committee: John W. Peters
Hydrogen may provide an avenue for a clean renewable fuel source, yet the methods to produce hydrogen are either extremely energy intensive, rely on fossil fuels, or require expensive noble metal catalysts. Biology may hold the keys necessary to unlocking new technologies that could change how hydrogen is produced. Microbial processes also produce hydrogen and harbor enzymes that carryout the reversible reduction of protons to hydrogen gas. These enzymes are capable of producing hydrogen at high rates comparable to platinum catalysts, but biological hydrogen catalysts can produce hydrogen using abundant elements carbon, oxygen, nitrogen, sulfur, iron, nickel and selenium. Biological hydrogen catalysts are termed hydrogenases, and though hydrogenases use abundant elements they are extraordinarily complex. This has made it difficult to construct model complexes using inorganic synthesis that can replicate the activities of their biological counterparts. One way to circumvent this problem is to use microbial hydrogen production and let microbes produce and maintain these enzymes inside a cell. Microbial hydrogen production also has the added benefit that hydrogen production could be engineered to connect with other metabolic processes such as photosynthesis and fermentation. Engineering microbes for hydrogen production could eventually allow for the production of hydrogen using inexpensive energy inputs such as solar energy or waste materials. Yet, there are many barriers that need to be overcome in order to engineer a robust microbial organism. One of the primary difficulties of developing this technology has been the oxygen sensitivity of hydrogenases. Hydrogenases when exposed to atmospheric concentrations of oxygen either completely inactivate or their rates are significantly slowed. To engineer a hydrogenase that is more amenable for microbial hydrogen production, the optimization of expressing and purifying hydrogenase enzymes has been developed. Methodologies have been developed to characterize how oxygen inactivates hydrogenase enzymes, and a new methodology has been explored to help find novel hydrogenase gene sequences that may help in engineering oxygen tolerant enzymes.
Bathymetric effects on marine hydrokinetic array performance
(Montana State University - Bozeman, College of Engineering, 2015) Peebles, Garrett William; Chairperson, Graduate Committee: Erick Johnson
Approximately 16% of the globally generated electricity comes from conventional hydropower installations. Recent technological improvements in marine hydrokinetics (MHK), and a global demand for increased renewable energy, are enabling this technology to become a major contributor in the global energy market. MHK devices convert the kinetic energy, or energy of motion, from waves or water currents into electricity that is then transferred to the electrical grid. Wave energy converters (WECs) capitalize on the oscillatory motion of ocean waves, while current energy converters (CECs) use river, tidal, or ocean currents to generate electricity and often resemble wind turbines. Unlike wind, water currents are less intermittent, and, in the case of tidal currents, highly predictable. At present scales, individual CEC and WEC devices alone are not powerful enough to make hydrokinetic power economically feasible. Therefore, deployment of arrays of marine hydrokinetic devices is the most cost-effective method for these devices to become a major contributor in the energy market. In addition to device design and operational conditions, how these devices are deployed within a site determines their potential for power generation. The power generated depends upon interdevice proximity, where it is generally assumed more electricity is generated as the spacing between each device increases. However, most array performance studies of current-energy converters do not consider bed topography and are either inside smooth walled channels or deep, open waters. The research presented here explores the impact of site bathymetry on array performance since each deployment location is likely to have a significant impact on the optimality of an array layout. It is first shown that without boundary constraints the performance of an array does improve as the inter-device spacing is increased. Uniquely though, the normalized power and loading on an array is not transferable from an unconstrained domain to simple, sloping beds. The effects of this demonstrate the need to consider the topography of real world locations for general array designs.
Insights into key barriers in the implementation of renewable biofuel technologies
(Montana State University - Bozeman, College of Letters & Science, 2013) Therien, Jesse Beau; Chairperson, Graduate Committee: John W. Peters; Keith E. Cooksey, Matthew C. Posewitz, and John W. Peters were co-authors of the article, 'Extended hydrogen production by alginate-immobilized, sulfur-deprived Chlamydomonas reinhardtii' submitted to the journal 'International journal of hydrogen energy' which is contained within this thesis.; Oleg A. Zadvornyy and John W. Peters were co-authors of the article, 'Phototroph co-culturing for the optimal production of biofuels' submitted to the journal 'Biotechnology for biofuels' which is contained within this thesis.; Trinity L. Hamilton, Donald A. Bryant, Zhenfeng Liu, Seth M. Noone, Paul W. King, and John W. Peters were co-authors of the article, 'Genome of Clostridium pasteurianum, transcriptional analysis and structural determinants of its hydrogenases' submitted to the journal 'Journal of bacteriology' which is contained within this thesis.
Bioenergy can be defined as renewable energy derived from biological sources. As world energy consumption increases and fossil fuel supplies are depleted, national and international energy requirements will become more diverse and more complicated. Clearly, the niche that alternative and renewable energy sources occupy in the energy portfolio will continue to increase over time. Currently, bioenergy in the form of biofuel production including alcohols, lipids, and hydrogen represent working technologies that are in large part only economically limited where large scale production is currently too costly to compete with fossil fuels. As a result, there has been a significant investment in basic science research to make these technologies more robust and more amenable to scale up. This includes large scale cultures of model biofuel producing organisms, consortia of organisms, and even mimetic systems in which components derived from biological sources are incorporated into materials. The success of future biofuel technologies is dependent on advancing these technologies by overcoming some of the key barriers that decrease the practicality of wide scale implementation. A key to the large scale production of biofuels in the form of alcohols, lipids, or hydrogen is to develop mechanisms to limit the costs associated with culturing organisms and harvesting fuels. A technique used to facilitate the production of bio-hydrogen from eukaryotic algae is described and shows promise as a way to reduce costs associated with handling microorganisms used in bioreactors. Immobilization the hydrogen producing alga Chlamydomonas reinhardtii in calcium alginate facilitates manipulation of culture conditions during biofuel production and their subsequent harvest. The design of tailored microbial consortia or co-culturing multiple organisms provides a means of simplifying and reducing costs of media components required for biofuel production by providing key media components metabolically. Finally, genomic and gene expression studies have provided clues into structural determinants responsible for superior hydrogen production by certain enzymes that can be incorporated into model hydrogen producing organisms or merged into biomaterials. Together, these studies have contributed to the progression and knowledge of bioenergy promoting an increasing and long lasting presence of renewable fuels in the global energy portfolio.
Algal biofilms, microbial fuel cells, and implementation of state-of-the-art research into chemical and biological engineering laboratories
(Montana State University - Bozeman, College of Engineering, 2010) Menicucci, Joseph Anthony Jr.; Chairperson, Graduate Committee: Ron Larsen
Alternative energy technologies become more attractive as the price of energy from fossil fuels becomes more expensive and the environmental concerns from their use mount. While a number of biological alternative energy technologies currently exist, a complete understanding of these technologies has yet to be developed. This dissertation characterizes an aspect of biological alternative energy technologies: the production of algal biofuels and energy conversion in microbial fuel cells. Specifically, this dissertation addresses the characterization of microalgae as a biofilm and the characterization of the power limitations of microbial fuel cells. The attachment and detachment of algae were observed using temporal microscopic imaging in a flow-cell with autofluorescence and staining techniques as part of a collaborative Montana State University and Idaho National Laboratory project. Colonies of algae exhibit many characteristics seen in bacterial biofilms: adherence; detachment and sloughing; difference in structure of an attached colony; varying strength of attachment on different surfaces; association of other organisms in an EPS matrix; and the heterogeneous nature of attached colonies. The characterization of a microbial fuel cell was completed in less than 30 minutes using an empirical procedure to predict the maximum sustainable power that can be generated by a microbial fuel cell over a short period of time. In this procedure, the external resistance was changed incrementally, in steps of 500 ohms every 60 seconds, and the anode potential, the cathode potential, and the cell current were measured. This procedure highlights the inherent limitations of energy conversion in a microbial fuel cell. A voltage/current characterization of the microbial fuel was also completed from the data collected. This dissertation also includes the evaluation of A Hands-On Introduction to Microbial Fuel Cells, a laboratory developed for an introductory chemical and biological engineering course. The experiment has been updated to include a voltage/current characterization of the microbial fuel cell. Learning objectives have been identified and pre- and post-laboratory activities have been developed for further implementation into a chemical and biological engineering curriculum.

Theses and Dissertations at Montana State University (MSU)

Browse

Filters

Settings

Sort By

Results per page

Search Results