Matching Items (83)
Description

This study analyzes the feasibility of using algae cultivated from wastewater effluent to produce a biodiesel feedstock. The goal was to determine if the energy produced was greater than the operational energy consumed without consideration to constructing the system as well as the emissions and economic value associated with the

This study analyzes the feasibility of using algae cultivated from wastewater effluent to produce a biodiesel feedstock. The goal was to determine if the energy produced was greater than the operational energy consumed without consideration to constructing the system as well as the emissions and economic value associated with the process.

Four scenarios were created:
       1) high-lipid, dry extraction.
       2) high-lipid, wet extraction.
       3) low-lipid, dry extraction.
       4) low-lipid, wet extraction.
In all cases, the system required more energy than it produced. In high lipid scenarios, the energy produced is close to the energy consumed, and a positive net energy balance may be achieved with minor improvements in technology or accounting for coproducts. In the low lipid scenarios, the energy balance is too negative to be considered feasible. Therefore the lipid content affects the decision to implement algae cultivation.

The dry extraction and the wet extraction both require some level of mechanical drying and this makes the two methods yield similar results in terms of the energy analysis. Therefore, the extraction method does not dramatically affect the decision for implementing algae-based oil production from an energetic standpoint. The economic value of the oil in both high lipid scenarios results in a net profit despite the negative net energy. Emission calculations resulted in avoiding a significant amount of CO2 for high lipid scenarios but not for the low lipid scenarios. The CO2 avoided does not account for non-lipid biomass, so this number is an underestimation of the final CO2 avoided from the end products.

While the term "CO2 avoided" has been used for this study, it should be noted that this CO2 would be emitted upon use as a fuel source. These emissions, however, are not “new” CO2 because it has already been emitted and is being captured and recycled. Currently, literature is very divisive on the lipid content present in algae and this study shows that lipid content has a tremendous affect on energy and emissions impacts. The type of algae that can grow in wastewater effluent also should be investigated as well as the conditions that promote high lipid accumulation. The dewatering phase must be improved as it is extremely energy intensive and dominates the operational energy balance.

In order to compete, wet extraction must have a much more significant effect on the drying phase and must avoid the use of the human toxicants methanol and chloroform. Additionally, while the construction phase was beyond the scope of this project it may be a critical aspect in determining the feasibility these systems. Future research in this field should focus on lipid production, optimizing the belt dryer or finding a different method of dewatering, and allocating the coproducts.

Created2012-05
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Description
Transformational sustainability science demands that stakeholders and researchers consider the needs and values of future generations in pursuit of solutions to sustainability problems. This dissertation research focuses on the real-world problem of unsustainable water governance in the Phoenix region of Central Arizona. A sustainability transition is the local water system

Transformational sustainability science demands that stakeholders and researchers consider the needs and values of future generations in pursuit of solutions to sustainability problems. This dissertation research focuses on the real-world problem of unsustainable water governance in the Phoenix region of Central Arizona. A sustainability transition is the local water system is necessary to overcome sustainability challenges and scenarios can be used to explore plausible and desirable futures to inform a transition, but this requires some methodological refinements. This dissertation refines scenario methodology to generate water governance scenarios for metropolitan Phoenix that: (i) feature enhanced stakeholder participation; (ii) incorporate normative values and preferences; (iii) focus on governance actors and their activities; and (iv) meet an expanded set of quality criteria. The first study in the dissertation analyzes and evaluates participatory climate change scenarios to provide recommendations for the construction and use of scenarios that advance climate adaptation and mitigation efforts. The second study proposes and tests a set of plausibility indications to substantiate or evaluate claims that scenarios and future projections could become reality, helping to establish the legitimacy of radically different or transformative scenarios among an extended peer community. The case study of water governance begins with the third study, which includes a current state analysis and sustainability appraisal of the Phoenix-area water system. This is followed by a fourth study which surveys Phoenix-area water decision-makers to better understand water-related preferences for use in scenario construction. The fifth and final study applies a multi-method approach to construct future scenarios of water governance in metropolitan Phoenix in 2030 using stakeholder preferences, among other normative frames, and testing systemic impacts with WaterSim 5.0, a dynamic simulation model of water in the region. The scenarios are boundary objects around which stakeholders can weigh tradeoffs, set priorities and reflect on impacts of water-related activities, broadening policy dialogues around water governance in central Arizona. Together the five studies advance transformational sustainability research by refining methods to engage stakeholders in crafting futures that define how individuals and institutions should operate in transformed and sustainable systems.
ContributorsKeeler, Lauren Withycombe (Author) / Wiek, Arnim (Thesis advisor) / White, Dave D (Committee member) / Lang, Daniel J (Committee member) / Arizona State University (Publisher)
Created2014
Description

The research topic for this assignment is shrimp farming in Thailand located throughout the coastal areas of the southern, eastern, and central regions of the country. Thailand’s huge shrimp export driven industry represents one of the largest in the world accounting for over twenty-five percent of food exports out of

The research topic for this assignment is shrimp farming in Thailand located throughout the coastal areas of the southern, eastern, and central regions of the country. Thailand’s huge shrimp export driven industry represents one of the largest in the world accounting for over twenty-five percent of food exports out of the country (Sriboonchitta & Wiboonpongse, n.d.).

Specific research questions include:
       1. What are the current unsustainable practices in shrimp farm production?
       2. In what part of the life cycle should intervention take place?
       3. What does a sustainable shrimp farming practice look like in the future?

Created2012-05
Description

Anticipatory LCA seeks to overcome the paucity of data through scenario development and thermodynamic bounding analyses. Critical components of anticipatory LCA include:
       1) Laboratory-scale inventory data collection for nano-manufacturing processes and
           preliminary performance evaluation.
       2) Thermodynamic modeling of manufacturing processes and developing scenarios

Anticipatory LCA seeks to overcome the paucity of data through scenario development and thermodynamic bounding analyses. Critical components of anticipatory LCA include:
       1) Laboratory-scale inventory data collection for nano-manufacturing processes and
           preliminary performance evaluation.
       2) Thermodynamic modeling of manufacturing processes and developing scenarios of     
           efficiency gains informed by analogous material processing industries.
       3) Use-phase bounding to report inventory data in a functional unit descriptive of
           performance.

Together, these analyses may call attention to environmentally problematic processes or nanotechnologies before significant investments in R&D and infrastructure contribute to technology lock in. The following case study applies these components of anticipatory LCA to single wall carbon nanotube (SWCNT) manufacturing processes, compares the rapid improvements in SWCNT manufacturing to historic reductions in the embodied energy of aluminum, and discusses the use of SWCNTs as free-standing anodes in advanced lithium ion batteries.

Created2012-05
Description

Sonoma County, CA is on an ambitious pathway to meeting stringent carbon emissions goals that are part of California Assembly Bill 32. At the county-level, climate planners are currently evaluating options to assist residents of the county in reducing their carbon footprint and also for saving money. The Sonoma County

Sonoma County, CA is on an ambitious pathway to meeting stringent carbon emissions goals that are part of California Assembly Bill 32. At the county-level, climate planners are currently evaluating options to assist residents of the county in reducing their carbon footprint and also for saving money. The Sonoma County Energy Independence Program (SCEIP) is one such county-level measure that is currently underway. SCEIP is a revolving loan fund that eligible residents may utilize to install distributed solar energy on their property. The fund operates like a property tax assessment, except that it only remains for a period of 20 years rather than in perpetuity.

This analysis intends to estimate the potential countywide effect that the $100M SCEIP fund might achieve on the C02 and cost footprint for the residential building energy sector. A functional unit of one typical home in the county is selected for a 25 year analysis period. Outside source data for the lifecycle emissions generated by the production, installation and operations of a PV system are utilized. Recent home energy survey data for the region is also utilized to predict a “typical” system size and profile that might be funded by the SCEIP program. A marginal cost-benefit calculation is employed to determine what size solar system a typical resident might purchase, which drives the life cycle assessment of the functional unit. Next, the total number of homes that might be financed by the SCEIP bond is determined in order to forecast the potential totalized effect on the County’s lifecycle emissions and cost profile.

The final results are evaluated and it is determined that the analysis is likely conservative in its estimation of the effects of the SCEIP program. This is due to the fact that currently offered subsidies are not utilized in the marginal benefit calculation for the solar system but do exist, the efficiency of solar technology is increasing, and the cost of a system over its lifecycle is currently decreasing. The final results show that financing distributed solar energy systems using Sonoma County money is a viable option for helping to meet state mandated goals and should be further pursued.

Created2012-05
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Description
The purpose of this quantitative study is to test the validity of a behavioral theory, value-belief-norm theory (Stern, 2000), in the context of environmental hotel management. The lack of theoretical consideration in previous studies on environmental attitudes of hotel/resort managers warrants an investigation of a theory with the potential to

The purpose of this quantitative study is to test the validity of a behavioral theory, value-belief-norm theory (Stern, 2000), in the context of environmental hotel management. The lack of theoretical consideration in previous studies on environmental attitudes of hotel/resort managers warrants an investigation of a theory with the potential to better explain behaviors that support the goals of environment management systems. The goal of this research was to document the values, beliefs, personal norms, and environmental management support behaviors of managers in a hospitality setting. Data were collected from a sample of hotel and resort managers in the Phoenix metropolitan area by using a survey of well-documented items from previous research on the theory. Results suggest the value-belief-norm theory is successful in explaining environmental management support behaviors. Implications for practitioners as well as researchers are discussed.
ContributorsRubin, Simon (Simon David) (Author) / White, Dave D (Thesis advisor) / Lee, Woojin (Committee member) / Basile, George (Committee member) / Arizona State University (Publisher)
Created2011
Description

Our objectives are to:
       1. Review the LCA literature to determine the dominant environmental impact categories in
           wild-caught fisheries in order to evaluate which phases are causing the greatest impacts.
       2. Determine how these impacts can best be mitigated and develop a

Our objectives are to:
       1. Review the LCA literature to determine the dominant environmental impact categories in
           wild-caught fisheries in order to evaluate which phases are causing the greatest impacts.
       2. Determine how these impacts can best be mitigated and develop a framework that seeks
           to incorporates LCA into sustainable seafood guides so that consumers can make better-
           informed decisions.

This framework will include developing meaningful LCA impact categories for sustainable seafood guides. Despite their importance, we considered social factors beyond the scope of this paper.

Created2012-05
Description

Our study calculates the estimated difference in water use, energy demands, and CO2 emissions of head lettuce associated with the production (land preparation and growing operations, chemical inputs, irrigation) and the transportation (diesel demand) to the Phoenix metro area from:
       1. A local level, defined here as within Maricopa

Our study calculates the estimated difference in water use, energy demands, and CO2 emissions of head lettuce associated with the production (land preparation and growing operations, chemical inputs, irrigation) and the transportation (diesel demand) to the Phoenix metro area from:
       1. A local level, defined here as within Maricopa County, Arizona (AZ).
       2. From the central coast of California (CA) in Monterey County.

Our research results demonstrate that local lettuce is more resource intensive than non-local or regional produce. Production in Maricopa County has significantly higher (more than double) energy demands and emissions than Monterey County. Irrigation and chemical inputs are the greatest contributors to energy demand in Maricopa, but it is primarily irrigation that contributes to emissions. Comparatively, transportation and chemical inputs are the greatest contributors to energy demand in Monterey, and it is primarily transportation that contributes to emissions.

This life cycle inventory suggests that we need to reconsider the “food miles” framing of the local food debate and whether local food production is a viable sustainable alternative to the current food system in the arid Southwest. However, we also recognize that factors beyond resource-use and emissions affect policymakers’ and consumers’ demands for local foods. Future studies ought to provide a more nuanced look at the issue that also includes social, psychological, and economic factors that influence food policies and purchases. These results have important implications for future water management and suggest the need to pursue more water efficient practices in AZ.

Created2012-05
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Description
As urban populations rapidly increase in an era of climate change and multiple social and environmental uncertainties, scientists and governments are cultivating knowledge and solutions for the sustainable growth and maintenance of cities. Although substantial literature focuses on urban water resource management related to both human and ecological sustainability, few

As urban populations rapidly increase in an era of climate change and multiple social and environmental uncertainties, scientists and governments are cultivating knowledge and solutions for the sustainable growth and maintenance of cities. Although substantial literature focuses on urban water resource management related to both human and ecological sustainability, few studies assess the unique role of waterway restorations to bridge anthropocentric and ecological concerns in urban environments. To address this gap, my study addressed if well-established sustainability principles are evoked during the nascent discourse of recently proposed urban waterway developments along over fifty miles of Arizona’s Salt River. In this study, a deductive content analysis is used to illuminate the emergence of sustainability principles, the framing of the redevelopment, and to illuminate macro-environmental discourses. Three sustainability principles dominated the discourse: civility and democratic governance; livelihood sufficiency and opportunity; and social-ecological system integrity. These three principles connected to three macro-discourses: economic rationalism; democratic pragmatism; and ecological modernity. These results hold implications for policy and theory and inform urban development processes for improvements to sustainability. As continued densification, in-fill and rapid urbanization continues in the 21st century, more cities are looking to reconstruct urban riverways. Therefore, the emergent sustainability discourse regarding potential revitalizations along Arizona’s Salt River is a manifestation of how waterways are perceived, valued, and essential to urban environments for anthropocentric and ecological needs.
ContributorsHorvath, Veronica (Author) / White, Dave D (Thesis advisor) / Mirumachi, Naho (Committee member) / Childers, Dan (Committee member) / Chester, Mikhail (Committee member) / Arizona State University (Publisher)
Created2019
Description

Meaningful sustainable consumption patterns require informed consumers who understand the actual impact of their actions on a quantitative and tangible basis. Life cycle assessment (LCA) is a tool well suited to achieving this goal, but has only been superficially applied to the analysis of plant-based diets. This analysis looks at

Meaningful sustainable consumption patterns require informed consumers who understand the actual impact of their actions on a quantitative and tangible basis. Life cycle assessment (LCA) is a tool well suited to achieving this goal, but has only been superficially applied to the analysis of plant-based diets. This analysis looks at a common component of plant-based meat alternatives: a wheat-based protein known as seitan, which is a common substitute for beef. A comparative consequential analysis shows the overall change in environmental impact when 1000 servings of seitan displace 1000 servings of beef. The functional unit for comparison is one serving of seitan or one serving of beef and the system boundaries include production but not distribution, consumption or disposal. Life cycles are created for seitan and beef in the LCA modeling software SimaPro and an analysis is run using the Eco-indicator 99 methodology. The beef life cycle is created using complete existing LCA data, while the seitan life cycle is created using LCA data for constituent materials and processes.

Findings indicate that beef is much more environmentally impactful than seitan, but the largest difference is found in land use change. Significant data quality and uncertainty issues exist due to the data being incomplete or not representative for US processes and the use of proxy processes to estimate industrial processing. This analysis is still useful as a screening tool to show rough differences in impact. It is noted that despite seitan having a lower environmental impact than beef, increasing seitan production will probably have the effect of increasing overall environmental impacts, as beef production is not likely to decrease as a result. Massive changes in consumer purchase patterns are required before reductions in impact can be expected. Recommendations for future work include expanding system boundaries and obtaining industry specific data for seitan production.

Created2012-05