Matching Items (62)
Description
The main objective of this project was to continue research and development of a building integrated solar thermoelectric generator (BISTEG). BISTEG is a promising renewable energy technology that is capable of generating electrical energy from the heat of concentrated sunlight. In order to perform R&D, the performance of different TEG cells and TEG setups were tested and analyzed, proof-of-concepts and prototypes were built. and the performance of the proof-of-concepts and prototypes were tested and analyzed as well. In order to test different TEG cells and TEG setups, a TEG testing apparatus was designed and fabricated. The apparatus is capable of comparing the performance of TEGs with temperature differentials up to 200 degrees C. Along with a TEG testing apparatus, several proof-of-concepts and prototypes were completed. All of these were tested in order to determine the feasibility of the design. All three proof-of-concepts were only capable of producing a voltage output less than 300mV. The prototype, however, was capable of producing a max output voltage of 17 volts. Although the prototype outperformed all of the proof-of-concepts, optimizations to the design can continue to improve the output voltage. In order to do so, stacked TEG tests were performed. After performing the stacked TEG tests, it was determined that the use of stacked TEGs depended on the Fresnel lens chosen. If BISTEG were to use a point focused Fresnel lens, using a stack of TEGs could increase the power density. If BISTEG were to utilize a linear focused Fresnel lens, however, the TEGs should not be stacked. It would be more efficient to lay them out side by side. They can be stacked, however, if the energy density needs to be increased and the costs of the additional TEGs are not an issue.
ContributorsPark, Andrew (Author) / Seager, Thomas (Thesis director) / Margaret, Hinrichs (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The purpose of this research is to study the effect of angle of acceptance and mechanical control system noise on the power available to a two-axis solar concentrating photovoltaic (CPV) system. The efficiency of a solar CPV system is greatly dependent on the accuracy of the tracking system because a strong focal point is needed to concentrate incident solar irradiation on the small, high efficiency cells. The objective of this study was to evaluate and quantify tracking accuracy for a performance model which would apply to similar two-axis systems. An analysis comparing CPV to traditional solar photovoltaics from an economic standpoint was conducted as well to evaluate the viability of emerging CPV technology. The research was performed using two calibrated solar radiation sensors mounted on the plane of the tracking system, normal to the sun. One sensor is held at a constant, normal angle (0 degrees) and the other is varied by a known interior angle in the range of 0 degrees to 10 degrees. This was to study the magnitude of the decrease in in irradiance as the angle deviation increases. The results show that, as the interior angle increases, the solar irradiance and thus available power available on the focal point will decrease roughly at a parabolic rate, with a sharp cutoff point at angles greater than 5 degrees. These findings have a significant impact on CPV system tracking mechanisms, which require high precision tracking in order to perform as intended.
ContributorsPodzemny, Dominic James (Author) / Reddy, Agami (Thesis director) / Kelman, Jonathan (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Bifacial photovoltaic modules are a relatively new development in the photovoltaic industry which allows for the collection and conversion of light on both sides of photovoltaic modules to usable electricity. Additional energy yield from bifacial photovoltaic modules, despite a slight increase in cost due to manufacturing processes of the bifacial cells, has the potential to significantly decrease the LCOE of photovoltaic installation. The performance of bifacial modules is dependent on three major factors: incident irradiation on the front side of the module, reflected irradiation on the back side of the module, and the module's bifaciality. Bifaciality is an inherent property of the photovoltaic cells and is determined by the performance of the front and rear side of the module when tested at STC. The reflected light on the back side of the module, however, is determined by several different factors including the incident ground irradiance, shading from the modules and racking system, height of the module installation, and ground albedo. Typical ground surfaces have a low albedo, which means that the magnitude of reflected light is a low percentage of the incident irradiance. Non-uniformity of back-side irradiance can also reduce the power generation due to cell-to-cell mismatch losses. This study investigates the use of controlled back-side reflectors to improve the irradiance on the back side of loosely packed 48-cell bifacial modules and compares this performance to the performance of 48 and 60-cell bifacial modules which rely on the uncontrolled reflection off nearby ground surfaces. Different construction geometries and reflective coating materials were tested to determine optimal construction to improve the reflectivity and uniformity of reflection. Results of this study show a significant improvement of 10-14% total energy production from modules with reflectors when compared to the 48-cell module with an uncontrolled ground reflection.
ContributorsBowersox, David Andrew (Author) / Tamizhmani, Govindasamy (Thesis director) / Srinivasan, Devarajan (Committee member) / School for Engineering of Matter, Transport and Energy (Contributor) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As more countries move toward renewable energy sources, universal acceptance is only a matter of time. It is no longer a question of if, but of when. For now, these types of energy sources can be too expensive or too complex for the average homeowner to acquire. A considerable financial investment and logistical specifications are required. My goal for this project is to create an analysis that will convey the most efficient and cost-effective way to move to a solar energy system without sacrificing output. There are many factors that go into the most practical and efficient strategy. These may include: solar tax credits, subsidies, rebates, panel type, utility company, among others. I hope to create an analysis that will enable anyone interested in taking advantage of solar power. The process outlined here will permit subjects to determine the best option for them, based on personal preferences and other related mitigating factors.
ContributorsStanley, John Richard (Author) / Simonson, Mark (Thesis director) / Ikram, Atif (Committee member) / Department of Finance (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
This paper introduces an excel tool created to improve the accuracy of electrical subcontracting prices for solar photovoltaic energy systems while also minimizing the time needed to create these price estimations. The need for improved precision, specifically during the early stages of a project, is examined and the paper also goes into detail about the components and pricing method that are incorporated into the excel tool. Lastly, the results of the price estimation tool are compared to real bids and recommendations are made for improvement to the tool.
ContributorsJohnson, Eric Allen (Author) / Fraser, Matthew (Thesis director) / Hjelmstad, Keith (Committee member) / Hughes, Jeff (Committee member) / Civil, Environmental and Sustainable Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Fresh water is essential to the human population and is an integral component in global economics for its multiple uses, and population growth/development cause concern for the possible exhaustion of the limited supply of freshwater. A combined computational and experimental approach to observe and evaluate pervaporation membrane performance for brackish water recovery was done to assess its efficiency and practicality for real world application. Results from modeling conveyed accuracy to reported parameter values from literature as well as strong dependence of performance on input parameters such as temperature. Experimentation results showed improved performance in flux by 34%-42% with radiative effect and then additional performance improvement (9%-33%) with the photothermal effect from carbon black application. Future work will include improvements to the model to include scaling propensity and energy consumption as well as continued experimentation to assess quality of pervaporation in water recovery.
ContributorsDurbin, Mitchell (Co-author) / Rivers, Frederick (Co-author) / Lind Thomas, MaryLaura (Thesis director) / Durgan, Pinar Cay (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Growing up in Ghana West Africa, I realized there were a few major obstacles hindering the education of the youth. One of them was the consistent supply of all year-round power. Therefore, pursuing a career in power electronics, I decided to research and implement a budget-friendly DC-AC converter that can take power from a DC source such as a solar panel to make AC power, suitable for grid-implementation. This project was undertaken with two other colleagues (Ian Vogt and Brett Fennelly), as our Senior Design Capstone project. My colleagues primarily researched into the "advanced" part of the converter such as Volt-VAR, Maximum Power Point Tracking (MPPT), and variable power factor, making the Capstone project be dubbed as "Smart Inverter". In this paper, I elaborate on the entire process of my research and simulation, through the design and layout of the PCB board to milling, soldering and testing. That was my contribution to the capstone project. After testing the board, it was concluded that although the inverter was intended to be the very inexpensive, some electrical and design principles could not be compromised. The converter did successfully invert DC power to AC, but it was only at low voltage levels; it could not withstand the higher voltages. This roadblock stymied the testing of advanced functionalities, paving way for an avenue of further research and implementation.
ContributorsAsigbekye, John (Author) / Ayyanar, Raja (Thesis director) / Sedillo, James (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
To compete with fossil fuel electricity generation, there is a need for higher efficiency solar cells to produce renewable energy. Currently, this is the best way to lower generation costs and the price of energy [1]. The goal of this Barrett Honors Thesis is to design an optical coating model that has five or fewer layers (with varying thickness and refractive index, within the above range) and that has the maximum reflectance possible between 950 and 1200 nanometers for normally incident light. Manipulating silicon monolayers to become efficient inversion layers to use in solar cells aligns with the Ira. A Fulton Schools of Engineering research themes of energy and sustainability [2]. Silicon monolayers could be specifically designed for different doping substrates. These substrates could range from common-used materials such as boron and phosphorus, to rare-earth doped zinc oxides or even fullerene blends. Exploring how the doping material, and in what quantity, affects solar cell energy output could revolutionize the current production methods and commercial market. If solar cells can be manufactured more economically, yet still retain high efficiency rates, then more people will have access to alternate, "green" energy that does not deplete nonrenewable resources.
ContributorsSanford, Kari Paige (Author) / Holman, Zachary (Thesis director) / Weigand, William (Committee member) / Industrial, Systems (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Testing was conducted for a solar assisted water heater and conventional all electric water heater for the purpose of investigating the advantages of utilizing solar energy to heat up water. The testing conducted simulated a four person household living in the Phoenix, Arizona region. With sensors and a weather station, data was gathered and analyzed for the water heaters. Performance patterns were observed that correlated to ambient conditions and functionality of the solar assisted water heater. This helped better understand how the solar water heater functioned and how it may continue to function. The testing for the solar assisted water heater was replicated with the all-electric water heater. One to one analyzes was conducted for comparison. The efficiency and advantages were displayed by the solar assisted water heater having a 61% efficiency. Performance parameters were calculated for the solar assisted water heater and it showed how accurate certified standards are. The results showed 8% difference in performance, but differed in energy savings. This further displayed the effects of uncontrollable ambient conditions and the effects of different testing conditions.
ContributorsMartínez, Luis, active 1995 (Author) / Rajadas, John (Thesis advisor) / Kannan, Arunachala (Committee member) / Rogers, Bradley (Committee member) / Arizona State University (Publisher)
Created2016
Description
The demand for cleaner energy technology is increasing very rapidly. Hence it is
important to increase the eciency and reliability of this emerging clean energy technologies.
This thesis focuses on modeling and reliability of solar micro inverters. In
order to make photovoltaics (PV) cost competitive with traditional energy sources,
the economies of scale have been guiding inverter design in two directions: large,
centralized, utility-scale (500 kW) inverters vs. small, modular, module level (300
W) power electronics (MLPE). MLPE, such as microinverters and DC power optimizers,
oer advantages in safety, system operations and maintenance, energy yield,
and component lifetime due to their smaller size, lower power handling requirements,
and module-level power point tracking and monitoring capability [1]. However, they
suer from two main disadvantages: rst, depending on array topology (especially
the proximity to the PV module), they can be subjected to more extreme environments
(i.e. temperature cycling) during the day, resulting in a negative impact to
reliability; second, since solar installations can have tens of thousands to millions of
modules (and as many MLPE units), it may be dicult or impossible to track and
repair units as they go out of service. Therefore identifying the weak links in this
system is of critical importance to develop more reliable micro inverters.
While an overwhelming majority of time and research has focused on PV module
eciency and reliability, these issues have been largely ignored for the balance
of system components. As a relatively nascent industry, the PV power electronics
industry does not have the extensive, standardized reliability design and testing procedures
that exist in the module industry or other more mature power electronics
industries (e.g. automotive). To do so, the critical components which are at risk and
their impact on the system performance has to be studied. This thesis identies and
addresses some of the issues related to reliability of solar micro inverters.
This thesis presents detailed discussions on various components of solar micro inverter
and their design. A micro inverter with very similar electrical specications in
comparison with commercial micro inverter is modeled in detail and veried. Components
in various stages of micro inverter are listed and their typical failure mechanisms
are reviewed. A detailed FMEA is conducted for a typical micro inverter to identify
the weak links of the system. Based on the S, O and D metrics, risk priority number
(RPN) is calculated to list the critical at-risk components. Degradation of DC bus
capacitor is identied as one the failure mechanism and the degradation model is built
to study its eect on the system performance. The system is tested for surge immunity
using standard ring and combinational surge waveforms as per IEEE 62.41 and
IEC 61000-4-5 standards. All the simulation presented in this thesis is performed
using PLECS simulation software.
important to increase the eciency and reliability of this emerging clean energy technologies.
This thesis focuses on modeling and reliability of solar micro inverters. In
order to make photovoltaics (PV) cost competitive with traditional energy sources,
the economies of scale have been guiding inverter design in two directions: large,
centralized, utility-scale (500 kW) inverters vs. small, modular, module level (300
W) power electronics (MLPE). MLPE, such as microinverters and DC power optimizers,
oer advantages in safety, system operations and maintenance, energy yield,
and component lifetime due to their smaller size, lower power handling requirements,
and module-level power point tracking and monitoring capability [1]. However, they
suer from two main disadvantages: rst, depending on array topology (especially
the proximity to the PV module), they can be subjected to more extreme environments
(i.e. temperature cycling) during the day, resulting in a negative impact to
reliability; second, since solar installations can have tens of thousands to millions of
modules (and as many MLPE units), it may be dicult or impossible to track and
repair units as they go out of service. Therefore identifying the weak links in this
system is of critical importance to develop more reliable micro inverters.
While an overwhelming majority of time and research has focused on PV module
eciency and reliability, these issues have been largely ignored for the balance
of system components. As a relatively nascent industry, the PV power electronics
industry does not have the extensive, standardized reliability design and testing procedures
that exist in the module industry or other more mature power electronics
industries (e.g. automotive). To do so, the critical components which are at risk and
their impact on the system performance has to be studied. This thesis identies and
addresses some of the issues related to reliability of solar micro inverters.
This thesis presents detailed discussions on various components of solar micro inverter
and their design. A micro inverter with very similar electrical specications in
comparison with commercial micro inverter is modeled in detail and veried. Components
in various stages of micro inverter are listed and their typical failure mechanisms
are reviewed. A detailed FMEA is conducted for a typical micro inverter to identify
the weak links of the system. Based on the S, O and D metrics, risk priority number
(RPN) is calculated to list the critical at-risk components. Degradation of DC bus
capacitor is identied as one the failure mechanism and the degradation model is built
to study its eect on the system performance. The system is tested for surge immunity
using standard ring and combinational surge waveforms as per IEEE 62.41 and
IEC 61000-4-5 standards. All the simulation presented in this thesis is performed
using PLECS simulation software.
ContributorsManchanahalli Ranganatha, Arkanatha Sastry (Author) / Ayyanar, Raja (Thesis advisor) / Karady, George G. (Committee member) / Qin, Jiangchao (Committee member) / Arizona State University (Publisher)
Created2015