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- All Subjects: Sustainability
- Creators: Arizona State University
Description
In 2018, building energy use accounted for over 40% of total primary energy consumption in the United States; moreover, buildings account for ~40% of national CO2 emissions. One method for curbing energy use in buildings is to apply Demand Side Management (DSM) strategies, which focus on reducing the energy demand through various technological and operational approaches in different building sectors.
This PhD research examines the integration of DSM strategies in existing residential and commercial buildings in the Phoenix, Arizona metropolitan area, a hot-arid climate. The author proposes three different case studies to evaluate the effectiveness of one DSM strategy in buildings, namely the integration of Phase Change Materials (PCMs). PCMs store energy in the freezing process and use that stored energy in the melting process to reduce the energy demand. The goal of these case studies is to analyze the potential of each strategy to reduce peak load and overall energy consumption in existing buildings.
First, this dissertation discusses the efficacy of coupling PCMs with precooling strategies in residential buildings to reduce peak demand. The author took a case study approach and simulated two precooling strategies, with and without PCM integration, in two sample single-family homes to assess the impact of the DSM strategies (i.e., precooling and PCM integration) on load shifting and load shedding in each home.
Second, this research addresses the feasibility of using PCMs as sensible and latent heat storage in commercial buildings. The author documents the process of choosing buildings for PCM installation, as well as the selection of PCMs for retrofitting purposes. Commercial building case studies compare experimental and simulation results, focusing on the impact of the PCMs on reducing the total annual energy demand and energy cost.
Finally, this research proposes a novel process for selecting PCMs as energy efficiency measures for building retrofits. This process facilitates the selection of a building and PCM that are complementary. Implementation of this process has not yet been tested; however, the process was developed based on experimental and simulation results from prior studies, and it would alleviate many of the PCM performance issues documented in those studies.
This PhD research examines the integration of DSM strategies in existing residential and commercial buildings in the Phoenix, Arizona metropolitan area, a hot-arid climate. The author proposes three different case studies to evaluate the effectiveness of one DSM strategy in buildings, namely the integration of Phase Change Materials (PCMs). PCMs store energy in the freezing process and use that stored energy in the melting process to reduce the energy demand. The goal of these case studies is to analyze the potential of each strategy to reduce peak load and overall energy consumption in existing buildings.
First, this dissertation discusses the efficacy of coupling PCMs with precooling strategies in residential buildings to reduce peak demand. The author took a case study approach and simulated two precooling strategies, with and without PCM integration, in two sample single-family homes to assess the impact of the DSM strategies (i.e., precooling and PCM integration) on load shifting and load shedding in each home.
Second, this research addresses the feasibility of using PCMs as sensible and latent heat storage in commercial buildings. The author documents the process of choosing buildings for PCM installation, as well as the selection of PCMs for retrofitting purposes. Commercial building case studies compare experimental and simulation results, focusing on the impact of the PCMs on reducing the total annual energy demand and energy cost.
Finally, this research proposes a novel process for selecting PCMs as energy efficiency measures for building retrofits. This process facilitates the selection of a building and PCM that are complementary. Implementation of this process has not yet been tested; however, the process was developed based on experimental and simulation results from prior studies, and it would alleviate many of the PCM performance issues documented in those studies.
ContributorsAskari Tari, Neda (Author) / Parrish, Kristen (Thesis advisor) / Bryan, Harvey (Committee member) / Reddy, T. Agami (Committee member) / Arizona State University (Publisher)
Created2020
Description
The circular economy is viewed as a solution to many of the environmental and social ills that the linear economy has exacerbated. Whether it is through refill solutions or redesigning a cardboard shipping container, fast-moving consumer goods (FMCG) brands are rethinking the way their products are delivered to consumers through business model innovations that promote circularity. The consumer plays the important, often overlooked, role of enabler within circular business models. This study aims to increase broader understanding of what motivates circular consumption of fast-moving consumer goods while analyzing the relationship between motivators and the behaviors required to participate. Semi-structured interviews provide insights from consumers who are currently purchasing household cleansers from brands that operate with a circular business model. Results from this study highlight a group of consumers that are distinguished by their common desire to reduce their personal consumption of plastics. There is clear indication that these consumers are in fact seeking out ways to consume more sustainably. A significant subset of this group expresses concern regarding ingredients used in the products. Health concerns for themselves, their family, or a pet are driving a desire to understand product ingredients. There is evidence to indicate that the concern for personal consumption of plastics is being driven by information distributed via social media and supported by targeted advertisements for brands that address this concern.
ContributorsBrown, Jennifer B (Author) / Dooley, Kevin (Thesis advisor) / Fischer, Daniel (Committee member) / Buch, Rajesh (Committee member) / Arizona State University (Publisher)
Created2020
Description
Humans have modified land systems for centuries in pursuit of a wide range of social and ecological benefits. Recent decades have seen an increase in the magnitude and scale of land system modification (e.g., the Anthropocene) but also a growing recognition and interest in generating land systems that balance environmental and human well-being. This dissertation focused on three case studies operating at distinctive spatial scales in which broad socio-economic or political-institutional drivers affected land systems, with consequences for the environmental conditions of that system. Employing a land system architecture (LSA) framework and using landscape metrics to quantify landscape composition and configuration from satellite imagery, each case linked these drivers to changes in LSA and environmental outcomes.
The first paper of this dissertation found that divergent design intentions lead to unique trajectories for LSA, the urban heat island effect, and bird community at two urban riparian sites in the Phoenix metropolitan area. The second paper examined institutional shifts that occurred during Cuba’s “special period in time of peace” and found that the resulting land tenure changes both modified and maintained the LSA of the country, changing cropland but preserving forest land. The third paper found that globalized forces may be contributing to the homogenizing urban form of large, populous cities in China, India, and the United States—especially for the ten largest cities in each country—with implications for surface urban heat island intensity. Expanding knowledge on social drivers of land system and environmental change provides insights on designing landscapes that optimize for a range of social and ecological trade-offs.
The first paper of this dissertation found that divergent design intentions lead to unique trajectories for LSA, the urban heat island effect, and bird community at two urban riparian sites in the Phoenix metropolitan area. The second paper examined institutional shifts that occurred during Cuba’s “special period in time of peace” and found that the resulting land tenure changes both modified and maintained the LSA of the country, changing cropland but preserving forest land. The third paper found that globalized forces may be contributing to the homogenizing urban form of large, populous cities in China, India, and the United States—especially for the ten largest cities in each country—with implications for surface urban heat island intensity. Expanding knowledge on social drivers of land system and environmental change provides insights on designing landscapes that optimize for a range of social and ecological trade-offs.
ContributorsStuhlmacher, Michelle (Author) / Turner, II, Billie L. (Thesis advisor) / Georgescu, Matei (Thesis advisor) / Frazier, Amy E. (Committee member) / Kim, Yushim (Committee member) / Arizona State University (Publisher)
Created2020
Description
Employee-owned businesses, benefit corporations, social enterprises, and other sustainability entrepreneurship innovations are responding to challenges such as climate change, economic inequalities, and unethical business behavior. Academic programs to date, however, often fall short in sufficiently equipping students with competencies in sustainability entrepreneurship – from a coherent set of learning objectives, through effective and engaging pedagogies, to rigorous assessment of learning outcomes. This dissertation contributes to bridging these gaps. The first study proposes a process-oriented and literature-based framework of sustainability entrepreneurship competencies. It offers a general vision for students, faculty, and entrepreneurs, as well as for the design of curricula, courses, and assessments. The second study presents an exploration into the nature of sustainability entrepreneurship courses, with a focus on teaching and learning processes. Using pioneering courses at Arizona State University, the study analyzes and compares the links between learning objectives, pedagogies, and learning outcomes. Based on document analysis and semi-structured interviews with course instructors, the study identifies cognitive apprenticeship from input processing to experimentation, constructive alignment from learning objectives to assessments, and curriculum-level coordination across courses as key success factors of sustainability entrepreneurship education. The result of this study can inform instructors and researchers in applying and further substantiating effective educational models for future entrepreneurs. The third study addresses the key question of competence assessment: what are reliable tools for assessing students’ competence in sustainability entrepreneurship? This study developed and tested a novel tool for assessing students’ competence in sustainability entrepreneurship through in-vivo simulated professional situations. The tool was in different settings and evaluated against a set of criteria derived from the literature. To inform educators in business and management programs, this study discusses and concludes under which conditions this assessment tool seems most effective, as well as improvement for future applications of the tool.
ContributorsFoucrier, Tamsin (Author) / Wiek, Arnim (Thesis advisor) / Basile, George (Thesis advisor) / Barth, Matthias (Committee member) / Arizona State University (Publisher)
Created2020
Description
As the global community raises concerns regarding the ever-increasing urgency of climate change, efforts to explore innovative strategies in the fight against this anthropogenic threat is growing. Along with other greenhouse gas mitigation technologies, Direct Air Capture (DAC) or the technology of removing carbon dioxide directly from the air has received considerable attention. As an emerging technology, the cost of DAC has been the prime focus not only in scientific society but also between entrepreneurs and policymakers. While skeptics are concerned about the high cost and impact of DAC implementation at scales comparable to the magnitude of climate change, industrial practitioners have demonstrated a pragmatic path to cost reduction. Based on the latest advancements in the field, this dissertation investigates the economic feasibility of DAC and its role in future energy systems. With a focus on the economics of carbon capture, this work compares DAC with other carbon capture technologies from a systemic perspective. Moreover, DAC’s major expenses are investigated to highlight critical improvements necessary for commercialization. In this dissertation, DAC is treated as a backstop mitigation technology that can address carbon dioxide emissions regardless of the source of emission. DAC determines the price of carbon dioxide removal when other mitigation technologies fall short in meeting their goals. The results indicate that DAC, even at its current price, is a reliable backup and is competitive with more mature technologies such as post-combustion capture. To reduce the cost, the most crucial component of a DAC design, i.e., the sorbent material, must be the centerpiece of innovation. In conclusion, DAC demonstrates the potential for not only negative emissions (carbon dioxide removal with the purpose of addressing past emissions), but also for addressing today’s emissions. The results emphasize that by choosing an effective scale-up strategy, DAC can become sufficiently cheap to play a crucial role in decarbonizing the energy system in the near future. Compared to other large-scale decarbonization strategies, DAC can achieve this goal with the least impact on our existing energy infrastructure.
ContributorsAzarabadi, Habib (Author) / Lackner, Klaus S (Thesis advisor) / Allenby, Braden R. (Committee member) / Dirks, Gary W (Committee member) / Reddy, Agami (Committee member) / Arizona State University (Publisher)
Created2020
Description
Participatory approaches to policy-making and research are thought to “open up” technical decision-making to broader considerations, empower diverse public audiences, and inform policies that address pluralistic public goods. Many studies of participatory efforts focus on specific features or outcomes of those efforts, such as the format of a participatory event or the opinions of participants. While valuable, such research has not resolved conceptual problems and critiques of participatory efforts regarding, for example, their reinforcement of expert perspectives or their inability to impact policy- and decision-making. I studied two participatory efforts using survey data collected from participants, interviews with policy makers and experts associated with each project, and an analysis of project notes, meeting minutes, and my own personal reflections about each project. Both projects were based one type of participatory effort called Participatory Technology Assessment (pTA). I examined how project goals, materials, and the values, past experiences, and judgments of practitioners influenced decisions that shaped two participatory efforts to better understand how practitioners approached the challenges associated with participatory efforts.
I found four major themes that influenced decisions about these projects: Promoting learning; building capacity to host pTA events; fostering good deliberation; and policy relevance. Project organizers engaged in iterative discussions to negotiate how learning goals related to dominant ideas from policy and expert communities and frequently reflected on the impact of participatory efforts on participants and on broader socio-political systems. Practitioners chose to emphasize criteria for deliberation that were flexible and encompassing. They relied heavily on internal discussions about materials and format, and on feedback collected from participants, policy makers, and other stakeholders, to shape both projects, though some decisions resulted in unexpected and undesirable outcomes for participant discussions and policy relevance. Past experience played a heavy role in many decisions about participatory format and concerns about deliberative or participatory theory were only nominally present. My emphasis on understanding the practice of participatory efforts offers a way to reframe research on participatory efforts away from studying ‘moments’ of participation to studying the larger role participatory efforts play in socio-political systems.
I found four major themes that influenced decisions about these projects: Promoting learning; building capacity to host pTA events; fostering good deliberation; and policy relevance. Project organizers engaged in iterative discussions to negotiate how learning goals related to dominant ideas from policy and expert communities and frequently reflected on the impact of participatory efforts on participants and on broader socio-political systems. Practitioners chose to emphasize criteria for deliberation that were flexible and encompassing. They relied heavily on internal discussions about materials and format, and on feedback collected from participants, policy makers, and other stakeholders, to shape both projects, though some decisions resulted in unexpected and undesirable outcomes for participant discussions and policy relevance. Past experience played a heavy role in many decisions about participatory format and concerns about deliberative or participatory theory were only nominally present. My emphasis on understanding the practice of participatory efforts offers a way to reframe research on participatory efforts away from studying ‘moments’ of participation to studying the larger role participatory efforts play in socio-political systems.
ContributorsWeller, Nicholas, Ph.D (Author) / Childers, Daniel L. (Thesis advisor) / Bennett, Ira (Committee member) / Coseo, Paul (Committee member) / Klinsky, Sonja (Committee member) / Arizona State University (Publisher)
Created2019
Description
Breeding seeds to include desirable traits (increased yield, drought/temperature resistance, etc.) is a growing and important method of establishing food security. However, besides breeder intuition, few decision-making tools exist that can provide the breeders with credible evidence to make decisions on which seeds to progress to further stages of development. This thesis attempts to create a chance-constrained knapsack optimization model, which the breeder can use to make better decisions about seed progression and help reduce the levels of risk in their selections. The model’s objective is to select seed varieties out of a larger pool of varieties and maximize the average yield of the “knapsack” based on meeting some risk criteria. Two models are created for different cases. First is the risk reduction model which seeks to reduce the risk of getting a bad yield but still maximize the total yield. The second model considers the possibility of adverse environmental effects and seeks to mitigate the negative effects it could have on the total yield. In practice, breeders can use these models to better quantify uncertainty in selecting seed varieties
ContributorsOzcan, Ozkan Meric (Author) / Armbruster, Dieter (Thesis advisor) / Gel, Esma (Thesis advisor) / Sefair, Jorge (Committee member) / Arizona State University (Publisher)
Created2019
Description
Demand for green energy alternatives to provide stable and reliable energy
solutions has increased over the years which has led to the rapid expansion of global
markets in renewable energy sources such as solar photovoltaic (PV) technology. Newest
amongst these technologies is the Bifacial PV modules, which harvests incident radiation
from both sides of the module. The overall power generation can be significantly increased
by using these bifacial modules. The purpose of this research is to investigate and maximize
the effect of back reflectors, designed to increase the efficiency of the module by utilizing
the intercell light passing through the module to increase the incident irradiance, on the
energy output using different profiles placed at varied distances from the plane of the array
(POA). The optimum reflector profile and displacement of the reflector from the module
are determined experimentally.
Theoretically, a 60-cell bifacial module can produce 26% additional energy in
comparison to a 48-cell bifacial module due to the 12 excess cells found in the 60-cell
module. It was determined that bifacial modules have the capacity to produce additional
energy when optimized back reflectors are utilized. The inverted U reflector produced
higher energy gain when placed at farther distances from the module, indicating direct
dependent proportionality between the placement distance of the reflector from the module
and the output energy gain. It performed the best out of all current construction geometries
with reflective coatings, generating more than half of the additional energy produced by a
densely-spaced 60-cell benchmark module compared to a sparsely-spaced 48-cell reference
module.ii
A gain of 11 and 14% was recorded on cloudy and sunny days respectively for the
inverted U reflector. This implies a reduction in the additional cells of the 60-cell module
by 50% can produce the same amount of energy of the 60-cell module by a 48-cell module
with an inverted U reflector. The use of the back reflectors does not only affect the
additional energy gain but structural and land costs. Row to row spacing for bifacial
systems(arrays) is reduced nearly by half as the ground height clearance is largely
minimized, thus almost 50% of height constraints for mounting bifacial modules, using
back reflectors resulting in reduced structural costs for mounting of bifacial modules
solutions has increased over the years which has led to the rapid expansion of global
markets in renewable energy sources such as solar photovoltaic (PV) technology. Newest
amongst these technologies is the Bifacial PV modules, which harvests incident radiation
from both sides of the module. The overall power generation can be significantly increased
by using these bifacial modules. The purpose of this research is to investigate and maximize
the effect of back reflectors, designed to increase the efficiency of the module by utilizing
the intercell light passing through the module to increase the incident irradiance, on the
energy output using different profiles placed at varied distances from the plane of the array
(POA). The optimum reflector profile and displacement of the reflector from the module
are determined experimentally.
Theoretically, a 60-cell bifacial module can produce 26% additional energy in
comparison to a 48-cell bifacial module due to the 12 excess cells found in the 60-cell
module. It was determined that bifacial modules have the capacity to produce additional
energy when optimized back reflectors are utilized. The inverted U reflector produced
higher energy gain when placed at farther distances from the module, indicating direct
dependent proportionality between the placement distance of the reflector from the module
and the output energy gain. It performed the best out of all current construction geometries
with reflective coatings, generating more than half of the additional energy produced by a
densely-spaced 60-cell benchmark module compared to a sparsely-spaced 48-cell reference
module.ii
A gain of 11 and 14% was recorded on cloudy and sunny days respectively for the
inverted U reflector. This implies a reduction in the additional cells of the 60-cell module
by 50% can produce the same amount of energy of the 60-cell module by a 48-cell module
with an inverted U reflector. The use of the back reflectors does not only affect the
additional energy gain but structural and land costs. Row to row spacing for bifacial
systems(arrays) is reduced nearly by half as the ground height clearance is largely
minimized, thus almost 50% of height constraints for mounting bifacial modules, using
back reflectors resulting in reduced structural costs for mounting of bifacial modules
ContributorsMARTIN, PEDRO JESSE (Author) / Tamizhmani, Govindasamy (Thesis advisor) / Phelan, Patrick (Committee member) / Wang, Liping (Committee member) / Arizona State University (Publisher)
Created2019
Description
Sustainable food systems have been studied extensively in recent times and the Food-Energy-Water (FEW) nexus framework has been one of the most common frameworks used. The dissertation intends to examine and quantitatively model the food system interaction with the energy system and the water system. Traditional FEW nexus studies have focused on food production alone. While this approach is informative, it is insufficient since food is extensively traded. Various food miles studies have highlighted the extensive virtual energy and virtual water footprint of food. This highlights the need for transport, and storage needs to be considered as part of the FEW framework. The Life cycle assessment (LCA) framework is the best available option to estimate the net energy and water exchange between the food, energy, and water systems. Climate plays an important role in food production as well as food preservation. Crops are very sensitive to temperature changes and it directly impacts a crop’s productivity. Changing temperatures directly impact crop productivity, and water demand. It is important to explore the feasibility of mitigation measures to keep in check increasing agricultural water demands. Conservation technologies may be able to provide the necessary energy and water savings. Even under varying climates it might be possible to meet demand for food through trade. The complex trade network might have the capacity to compensate for the produce lost due to climate change, and hence needs to be established. Re-visualizing the FEW nexus from the consumption perspective would better inform policy on exchange of constrained resources as well as carbon footprints. This puts the FEW nexus research space a step towards recreating the FEW nexus as a network of networks, that is, FEW-e (FEW exchange) nexus.
ContributorsNatarajan, Mukunth (Author) / Chester, Mikhail (Thesis advisor) / Lobo, Jose (Committee member) / Ruddell, Benjamin (Committee member) / Fraser, Andrew (Committee member) / Arizona State University (Publisher)
Created2019
Description
Urban community gardens hold the potential to serve as a form of multifunctional green infrastructure to advance urban sustainability goals through the array of ecosystem services they afford. While a substantial body of literature has been produced that is dedicated to the study of these services (e.g., providing fresh produce, promoting socialization, and enhancing urban biodiversity), less attention has been paid to the strategic planning of urban community gardens, particularly in an expansive urban setting, and in the context of the co-benefit of mitigating extreme heat. The research presented in this dissertation explores the potential of community gardens as a form of multifunctional green infrastructure and how these spaces can be planned in a manner that strives to be both systematic and transparent. It focuses on methods that can (1) be employed to identify vacant or open land plots for large metropolitan areas and (2) explores multicriteria decision analysis and (3) optimization approaches that assist in the selection of “green” spaces that serve as both provisioning (a source of fresh fruits and vegetables) and regulating (heat mitigation) services, among others. This exploration involves three individual studies on each of these themes, using the Phoenix metropolitan area as its analytical backdrop. The major lessons from this piece are: (1) remotely sensed data can be effectively paired with cadastral data to identify thousands of vacant parcels for potential greening at a metropolitan scale; (2) a stakeholder-weighted multicriteria decision analysis for community garden planning can serve as an effective decision support tool, but participants' conceptualization of garden spaces resulted in social criteria being prioritized over physical-environmental factors, potentially influencing the provisioning of co-benefits; and (3) optimized urban community garden networks hold the potential to synergistically distribute co-benefits across a large metropolitan area in a manner that systematically prioritizes high-need neighborhoods. The methods examined are useful for all metropolises with a preponderance of open or vacant land seeking to advance urban sustainability goals through green infrastructure.
ContributorsSmith, Jordan Paul (Author) / Turner, Billie L (Thesis advisor) / Meerow, Sara (Committee member) / Tong, Daoqin (Committee member) / Grebitus, Carola (Committee member) / Arizona State University (Publisher)
Created2021