Matching Items (8)
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Description
At present, almost 70% of the electric energy in the United States is produced utilizing fossil fuels. Combustion of fossil fuels contributes CO2 to the atmosphere, potentially exacerbating the impact on global warming. To make the electric power system (EPS) more sustainable for the future, there has been an emphasis

At present, almost 70% of the electric energy in the United States is produced utilizing fossil fuels. Combustion of fossil fuels contributes CO2 to the atmosphere, potentially exacerbating the impact on global warming. To make the electric power system (EPS) more sustainable for the future, there has been an emphasis on scaling up generation of electric energy from wind and solar resources. These resources are renewable in nature and have pollution free operation. Various states in the US have set up different goals for achieving certain amount of electrical energy to be produced from renewable resources. The Southwestern region of the United States receives significant solar radiation throughout the year. High solar radiation makes concentrated solar power and solar PV the most suitable means of renewable energy production in this region. However, the majority of the projects that are presently being developed are either residential or utility owned solar PV plants. This research explores the impact of significant PV penetration on the steady state voltage profile of the electric power transmission system. This study also identifies the impact of PV penetration on the dynamic response of the transmission system such as rotor angle stability, frequency response and voltage response after a contingency. The light load case of spring 2010 and the peak load case of summer 2018 have been considered for analyzing the impact of PV. If the impact is found to be detrimental to the normal operation of the EPS, mitigation measures have been devised and presented in the thesis. Commercially available software tools/packages such as PSLF, PSS/E, DSA Tools have been used to analyze the power network and validate the results.
ContributorsPrakash, Nitin (Author) / Heydt, Gerald T. (Thesis advisor) / Vittal, Vijay (Thesis advisor) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Fermentative bioproduction is an efficient production avenue for many small organic acids with less greenhouse gas emissions than petrochemical conversion. Export of these organic acids from the cell is proposed to be mediated by networks of transmembrane transport proteins. However characterization of full transporter networks or the substrate promiscuity of

Fermentative bioproduction is an efficient production avenue for many small organic acids with less greenhouse gas emissions than petrochemical conversion. Export of these organic acids from the cell is proposed to be mediated by networks of transmembrane transport proteins. However characterization of full transporter networks or the substrate promiscuity of individual transporters is often incomplete. Here, we used a cheminformatic approach to predict previously unknown native activity of E. coli transporters based on substrate promiscuity. Experimental validation in characterized several major putative malate exporters, whereas others were characterized as weak putative lactate exporters. The lactate export network remains incompletely characterized and might be mediated by a large, evolved network of promiscuous transporters.
ContributorsSchneider, Aidan (Author) / Wang, Xuan (Thesis director) / Varman, Arul (Committee member) / Nielsen, David (Committee member) / Department of Finance (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description

Ammonia is one of the most critical chemical commodities produced and is integral to a number of current industries such as agriculture as well as a key part to future sustainability areas such as clean H2 production. However, the current production methods for ammonia are largely unsustainable and produce large

Ammonia is one of the most critical chemical commodities produced and is integral to a number of current industries such as agriculture as well as a key part to future sustainability areas such as clean H2 production. However, the current production methods for ammonia are largely unsustainable and produce large amounts of CO2 emissions. This combined with the current dependence on fossil energy for production has led to researchers attempting to develop a clean and sustainable method for ammonia production. This method involves the thermochemical looping of a nitride compound with H2, and the renitridation of the compound with N2. This thermochemical loop would significantly reduce pressure requirements for ammonia production in addition to only being reliant on renewable inputs. This paper expands and complements this research by detailing the methods for the synthesis of nitride compounds as well as confirming their structure through material characterization. The nitride compounds as well as their oxide precursors were synthesized through Pechini synthesis and co-precipitation, and their structure was confirmed through the use of X-ray diffraction analysis. The XRD patterns of the synthesized nitrides matched those previously synthesized as well as those found in literature. In addition, observation of the spectra for the oxide CoMoO4 showed a marked similarity to that of the oxide precursor for (NixCox)2Mo3N. However, further testing is necessary regarding the phase-purity of synthesized nitrides, as well as the reduction and renitridation capability of nitrides in the line of (NixCox)2Mo3N.

ContributorsShakeel, Syed (Author) / Ermanoski, Ivan (Thesis director) / Miller, James (Committee member) / Barrett, The Honors College (Contributor) / Chemical Engineering Program (Contributor)
Created2023-05
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Description
The goal of any solar photovoltaic (PV) system is to generate maximum energy throughout its lifetime. The parameters that can affect PV module power output include: solar irradiance, temperature, soil accumulation, shading, encapsulant browning, encapsulant delamination, series resistance increase due to solder bond degradation and corrosion and shunt resistance decrease

The goal of any solar photovoltaic (PV) system is to generate maximum energy throughout its lifetime. The parameters that can affect PV module power output include: solar irradiance, temperature, soil accumulation, shading, encapsulant browning, encapsulant delamination, series resistance increase due to solder bond degradation and corrosion and shunt resistance decrease due to potential induced degradation, etc. Several PV modules together in series makes up a string, and in a power plant there are a number of these strings in parallel which can be referred to as an array. Ideally, PV modules in a string should be identically matched to attain maximum power output from the entire string. Any underperforming module or mismatch among modules within a string can reduce the power output. The goal of this project is to quickly identify and quantitatively determine the underperforming module(s) in an operating string without the use of an I-V curve tracer, irradiance sensor or temperature sensor. This goal was achieved by utilizing Radiovoltmeters (RVM). In this project, it is demonstrated that the voltages at maximum power point (Vmax) of all the individual modules in a string can be simultaneously and quantitatively obtained using RVMs at a single irradiance, single module operating temperature, single spectrum and single angle of incidence. By combining these individual module voltages (Vmax) with the string current (Imax) using a Hall sensor, the power output of individual modules can be obtained, quickly and quantitatively.
ContributorsTahghighi, Arash (Author) / Tamizhmani, Govindasamy (Thesis advisor) / Rogers, Bradley (Committee member) / Srinivasan, Devarajan (Committee member) / Arizona State University (Publisher)
Created2019
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Description
This thesis provides a cost to benefit analysis of the proposed next generation of distribution systems- the Future Renewable Electric Energy Distribution Management (FREEDM) system. With the increasing penetration of renewable energy sources onto the grid, it becomes necessary to have an infrastructure that allows for easy integration of these

This thesis provides a cost to benefit analysis of the proposed next generation of distribution systems- the Future Renewable Electric Energy Distribution Management (FREEDM) system. With the increasing penetration of renewable energy sources onto the grid, it becomes necessary to have an infrastructure that allows for easy integration of these resources coupled with features like enhanced reliability of the system and fast pro-tection from faults. The Solid State Transformer (SST) and the Fault Isolation Device (FID) make for the core of the FREEDM system and have huge investment costs.

Some key features of the FREEDM system include improved power flow control, compact design and unity power factor operation. Customers may observe a reduction in the electricity bill by a certain fraction for using renewable sources of generation. There is also a possibility of huge subsidies given to encourage use of renewable energy. This thesis is an attempt to quantify the benefits offered by the FREEDM system in monetary terms and to calculate the time in years required to gain a return on investments made. The elevated cost of FIDs needs to be justified by the advantages they offer. The result of different rates of interest and how they influence the payback period is also studied. The payback periods calculated are observed for viability. A comparison is made between the active power losses on a certain distribution feeder that makes use of distribution level magnetic transformers versus one that makes use of SSTs. The reduction in the annual active power losses in the case of the feeder using SSTs is translated onto annual savings in terms of cost when compared to the conventional case with magnetic transformers. Since the FREEDM system encourages operation at unity power factor, the need for installing capacitor banks for improving the power factor is eliminated and this re-flects in savings in terms of cost. The FREEDM system offers enhanced reliability when compared to a conventional system. The payback periods observed support the concept of introducing the FREEDM system.
ContributorsRaman, Apurva (Author) / Heydt, Gerald (Thesis advisor) / Karady, George G. (Committee member) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2015
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Description
Fossil fuels are currently the main source of energy in the world’s transportation sector. They are also the primary contributor to carbon emissions in the atmosphere, leading to adverse climate effects. The objective of the following research is to increase the yield and efficiency of algal biofuel in order to

Fossil fuels are currently the main source of energy in the world’s transportation sector. They are also the primary contributor to carbon emissions in the atmosphere, leading to adverse climate effects. The objective of the following research is to increase the yield and efficiency of algal biofuel in order to establish algal-derived fuel as a competitive alternative to predominantly used fossil fuels. Using biofuel commercially will reduce the cost of production and ultimately decrease additional carbon emissions. Experiments were performed using hydrothermal liquefaction (HTL) to determine which catalyst would enhance the algal biocrude oil and result in the highest quality biofuel product, as well as to find the optimal combination of processing temperature and manure co-liquefaction of biomass ratio. For the catalytic upgrading experiments, Micractenium Immerum algae was used in conjunction with pure H2, Pt/C, MO2C, and HZSM-5 catalysts at 350℃ and 400℃, 430 psi, and a 30-minute residence time to investigate the effects of catalyst choice and temperature on the crude oil yield. While all catalysts increased the carbon content of the crude oil, it was found that using HZSM-5 at 350℃ resulted in the greatest overall yield of about 75%. However, the Pt/C catalyst increased the HHV from 34.26 MJ/kg to 43.26 MJ/kg. Cyanidioschyzon merolae (CM) algae and swine manure were utilized in the co-liquefaction experiments, in ratios (algae to swine) of 80:20, 50:50, and 20:80 at temperatures of 300℃ and 330℃. It was found that a ratio of 80:20 at 330℃ produced the highest biocrude oil yield of 29.3%. Although the 80:20 experiments had the greatest biomass conversion and best supported the deacidification of the oil product, the biocrude oil had a HHV of 33.58 MJ/kg, the lowest between the three different ratios. However, all calorific values were relatively close to each other, suggesting that both catalytic upgrading and co-liquefaction can increase the efficiency and economic viability of algal biofuel.
ContributorsMurdock, Tessa A (Author) / Deng, Shuguang (Thesis director) / Varman, Arul (Committee member) / Chemical Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description

The goal of this research was to identify why the federal government should invest in solar research and development, and which areas of solar improvement should be focused on. Motivation for this can be found in the pressing need to prevent and reverse the effects of climate change, the inevitability

The goal of this research was to identify why the federal government should invest in solar research and development, and which areas of solar improvement should be focused on. Motivation for this can be found in the pressing need to prevent and reverse the effects of climate change, the inevitability of fossil fuel resources eventually running out, and the economic and job creation potential which solar energy holds. Additionally, it is important to note that the best course of action will involve a split of funding between current solar rollout and energy grid updating, and the R&D listed in this research. Upon examination, it can be seen that an energy revolution, led by a federal solar jobs program and a Green New Deal, would be both an ethically and economically beneficial solution. A transition from existing fossil fuel infrastructure to renewable, solar-powered infrastructure would not only be possible but highly beneficial in many aspects, including massive job creation, a more affordable, renewable energy solution to replace coal-fired plants, and no fuel spending or negotiation required.<br/>When examining which areas of solar improvement to focus on for R&D funding, four primary areas were identified, with solutions presented for each. These areas for improvement are EM capture, EM conversion efficiency, energy storage capacity, and the prevention of overheating. For each of these areas of improvement, affordable solutions that would greatly improve the efficiency and viability of solar as a primary energy source were identified. The most notable area that should be examined is solar storage, which would allow solar PV panels to overcome their greatest real and perceived obstacle, which is the inconsistent power generation. Solar storage is easily attainable, and with enough storage capacity, excess solar energy which would otherwise be wasted during the day can be stored and used during the night or cloudy weather as necessary. Furthermore, the implementation of highly innovative solutions, such as agrivoltaics, would allow for a solar revolution to occur.

ContributorsWhitlow, Hunter Marshall (Author) / Fong, Benjamin (Thesis director) / Andino, Jean (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

Out of all fifty states, Arizona boasts the greatest number of sunny days, which comes as no surprise to its residents. According to a CDC data report, Arizona has an average of nearly 286 total days of sun exposure. This sheer amount of sunlight could lead to the assumption that

Out of all fifty states, Arizona boasts the greatest number of sunny days, which comes as no surprise to its residents. According to a CDC data report, Arizona has an average of nearly 286 total days of sun exposure. This sheer amount of sunlight could lead to the assumption that Arizona is also leading the way in harvesting this solar energy, but that isn’t the case. According to the S.E.I.A (Solar Energies Industries Association), Arizona is the fifth largest solar producer, while California comes in first by a significant lead. What happened in the history of California that caused this disparity in solar production that we see today and should Arizona follow in its footsteps? In this video essay, I consider the historical impact that climate change has had on California that directly led them to adopt environmental policies, such as wildfires, droughts, smog, and sea-level rise. These events threaten California specifically, due to its uniquely high population, geography, and climate, and they will continue to get worse as climate change subsists. Due to the persistent threat that they face, California was forced to pass environmental regulations that ultimately ended up developing them into a leader in environmental protectionism. Arizona, while also facing droughts, high heat, and poor air quality, has had its environmental progress greatly hindered by a lack of cohesive action at the State level. Based on information from the U.S Energy Information Agency, over the past 30 years, Arizona has been one of, if not the highest, carbon-dioxide emitters in the West. For a time there was some political response to this fact, but eventually, its momentum was halted in favor of economic challenges and continually stunted by mixed agendas, which polarized Arizona parties even more and left city governments to deal with climate change on their own. With solar being the cheapest means of clean energy production, it seems unavoidable that it will develop eventually. Solar becoming a topic of such polarization in Arizona makes it much more challenging, as it can only progress with bipartisan support, but climate change is inevitable so discourse has to be the first step towards meaningful change.

ContributorsSalvaggio, Niko (Author) / Manfredo, Mark (Thesis director) / Englin, Jeffrey (Committee member) / Barrett, The Honors College (Contributor) / Dean, W.P. Carey School of Business (Contributor)
Created2022-05