Browsing by Subject "Water"
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Item A comparison of Berl saddles and Nor-Pac rings for absorption in the air-ammonia-water system(Texas Tech University, 1990-05) Caraway, Trina L.This research has two objectives. The first objective is to determine three conventional packed tower performance characteristics for each of two packings: 1/2-in. (nominal) ceramic Berl saddles and 5/8-in. (nominal) polypropylene Nor-Pac® rings. The characteristics are the gas-handling capacity; the height of a transfer unit; and the overall, gas-associated with each packing. The second objective is to compare these performance characteristics in order to determine which packing has the higher gas-handling capacity, the lower height of a transfer unit, and the higher overall, gas-side, mass-transfer coefficient. The first objective was met by obtaining experimental data from a single laboratory-scale gas absorber packed first with the Berl saddles, then with the Nor-Pac® rings when they became available. The data includes the pressure drop at various air and water flowrates, which was used to determine a set of flooding and loading points. The operating range and the gas-handling capacity associated with each packing were based on the flooding- and loading-point data. The packed tower was then used as an absorber to remove ammonia from air using water as the liquid solvent. The steady-state inlet and outlet compositions were used to calculate the number of transfer units (NTU), which represent the amount of contacting required to accomplish a phase enrichment, divided by the driving force in phatphase.^ The HTU values were obtained from the NTU and the height of the packed section. Subsequently, the HTU and other proces parameters were used to calculate KoG. The second objective was met by comparing the flooding points and operating ranges of each packing, as well as the HTUs and KQGS. These last two parameters were reported as functions of both the gas and the liquid flowrates.Item A qualitative investigation of the factors that influence crop planting and water management in West Texas(2008-12) Leigh, Kathryn; Doerfert, David; Fraze, Steven; Akers, CindyThe purpose of this study is to determine the factors that influence farmers in their planting decisions from year to year. The population for this study was be the farmers serving on the board of the Texas Alliance for Water Conservation (TAWC) project. The results of this study will be of benefit to businesses, and companies that depend on the farmer and his decisions for the success of their company. The study will also help policy.Item A study of the costs of quality in a renewable resource environment(Texas Tech University, 2009-05) Banasik, Marcus; Beruvides, Mario G.; Marcy, William M.; Smith, Milton L.; Pasewark, William R.; Simonton, James L.This study provides an in depth literature review of the cost of quality (COQ) research, a COQ compendium, a comparison between the COQ for a manufacturing meta-analysis and 3 water utilities and a sensitivity analysis of the water utilities. These water utilities are El Paso, Lubbock, and San Antonio. The Manufacturing Meta-Analysis consisted of 38 useable studies which included a variety of industries and manufacturing processes. These were used to develop the comparison populations for the prevention, appraisal, failure, and total COQ variables against the water utilities. The water utilities were chosen because they represent three different populations, three difference water source combinations and three different county water usages. The three utilities together also represent 10% of the large water systems and approximately 11% of the population in Texas. Monthly financial data was collected from each water utility. Lubbock provided 33 observations, El Paso 45, and San Antonio 12 after the removal of outliers. This data was then categorized into the Prevention, Appraisal, and Failure (PAF) costs based on annual reports, budgets, utility input and the PAF Cost Compendium. The primary hypotheses of this research were to compare the COQ PAF and Total COQ ratios of the manufacturing meta-analysis with the water utilities to identify, determine the Juran Point for the water utilities and show that it is representative of a mature market, test the materiality of the Opportunity Costs, and determine the significance of the Environmental Opportunity Costs. The results of these hypotheses show that Prevention, Failure, and Total COQ are not the same for water utilities versus manufacturing companies. The Total COQ % for the water utilities was twice as large as the manufacturing companies. Interestingly, Appraisal costs were statistically the same between the water utilities and manufacturing utilities. Also, opportunity costs may or may not be material depending on the utility, but they were about $1M and $1-$2M for El Paso and San Antonio respectively. Hypotheses 2 and 4 were not able to be calculated from the information made available during the study. The sensitivity analysis also showed differences between the utilities. Population may have an impact on the % of Prevention costs. Appraisal costs were still equal across the water utilities. It also showed that wages were the single largest costs factor and that rainfall amounts have no effect on the costs of quality. The conclusions of this research are that differences do exist between water utility and manufacturing company COQ. Further research is needed to completely understand the causes of the differences. What is the reason that even with higher a high % prevention the water utilities have two times the % Total COQ? Are those differences due to risk aversion, public health, regulatory reasons, etc.? More research needs to be conducted to identify the Juran Point and Environmental Costs. The applications for this research is vast and includes over 3900 water utilities serving populations > 10,000, waste water utilities, energy utilities, and storm water utilities to name a few. This research is another tool that utilities could use to better allocate monetary resources to solve gaps in their funding.Item Achieving the minimum 20 percent conservation and reuse mandate in the SWIFT process in Texas(2015-05) Harris, Shannon Carrie; Steiner, Frederick R.; Lieberknecht, Katherine E.; Huber, Karen L.In November 2013, the citizens of Texas approved a new water infrastructure-financing plan called the State Water Implementation Fund for Texas (SWIFT). SWIFT funds will provide low-cost loans for water projects included in the State Water Plan. A few conditions catalyzed this historic legislation, including a year of exceptionally severe drought in 2011, and the 2012 State Water Plan, the first such plan released since 2007. This document assumes one scenario for water planning in Texas in which the population nearly doubles and historic dry periods persist, resulting in an 8.3 million acre feet water shortage. A minimum of 20 percent of the fund must finance conservation and reuse water supply and enhancement methods. These projects must have associated capital costs and be included in the State Water Plan. Conservation strategies often have no capital costs, or if they do, expenses are lower than for other techniques such as desalination. Therefore, this research seeks to discover whether it is possible to meet the 20 percent minimum set-aside. The study focuses mostly on conservation procedures since reuse typically incurs significantly higher costs, and could, theoretically, meet the set-aside alone. Texas water users must think strategically about conservation in order meet the minimum set-aside. In a state with a history of large infrastructure projects, such as 60 years of reservoir construction, planners are no longer in tune with a diverse array of potential projects. Alternative water enhancement techniques not only supply water, but provide benefits to the local ecology and economy. The research also explores alternative water conservation technologies. Texans are fiercely independent, pragmatic, innovative people by nature. The cultural history of the state underscores these facts. The SWIFT fund is a result of creative thinking by planners, legislators, and citizens to alleviate problems before they become serious. That same vision is necessary to inspire synergies between participants using auxiliary water technologies financed through new funding mechanisms resulted from changing economic philosophies. The citizens of the state, and its ecological health, will benefit if they can muster the political will to resourcefully meet the minimum 20 percent conservation and reuse set-aside.Item Aquatic macroinvertebrate diversity and water quality of urban lakes(Texas Tech University, 1996-05) Wolf, Craig F.Macroinvertebrate species diversity and community composition are important themes in aquatic ecology, and are often used to evaluate environmental stress resulting from a variety of anthropogenic disturbances. On the Southern High Plains of Texas, urban areas have incorporated lakes into their stormwater and surface-water management systems. Eight urban lakes were selected to include a range of physical and biological features (i.e., lake size, relative potential for nonpoint source pollution, and presence of aquatic vegetation) representative of urban lakes in Lubbock, Texas. These lakes were categorized into three a priori groups based on the above characteristics. I evaluated 16 physicochemical attributes on a monthly basis, from February 1993 to April 1994, and found that 12 of the attributes contributed significantly to differences among groups of lakes during the study. Macroinvertebrate community composition was sampled on six different dates in each lake to capture seasonal patterns in species diversity. No significant differences in species diversity (Fisher's log series a) existed among groups of lakes in the summer or for the combined seasons data, although significant differences did occur in the spring and fall. Groups of lakes that were signficantly different represent the extremes in habitat complexity and invertebrate community composition. Community composition of group 1 and 3 lakes were dominated by three to four families of invertebrates, whereas in group 2 lakes, over 60% of species abundance was attributed to one species. Mantel's nonparametric test found a significant association between matrices based on water quality similarities and macroinvertebrate similarities during the fall sampling period. Furthermore, stepwise multiple regression using invertebrate species abundances as the dependent variable and water quality characteristics as the independent variables found significant relationships between corixid, notonectid, chironomid, and cladoceran abundances and salinity, total phosphorus, dissolved oxygen, total organic carbon, and ammonia. These attributes accounted for 33-76% of the variation observed in the abundances of these species. Of the water quality characteristics found to be significant predictors of species abundances, salinity, ammonia, and total organic carbon were correlated significantly to areal extent of multiple family housing and commercial land-use surrounding each lake. These results suggest that land-use may indirectly influence macroinvertebrate community composition of urban lakes.Item Cairo ecologies : water in social and material cycles(2014-05) Farmer, Tessa Rose; Ali, Kamran Asdar, 1961-This dissertation investigates the ways in which the natural and the social overlap in the symbolic center of human activity, cities. Cities are full of living organisms, existing not in a perfect state of equilibrium but rather in states of constant flux. The cycles of life moving through the city of Cairo, Egypt are dependent on water as a vital component and scarce resource in systems of biological exchange, as well as one among many pieces of infrastructure that the city requires to survive. This dissertation looks at the informal systems that residents of a squatter settlement in Cairo, Egypt called Ezbet Khairallah have created to make life possible, as well as their attempts to get the state to formally provide these services; work that is done at collective scales and in everyday practices. The dissertation also looks at what happens when areas such as Ezba are successful in getting the state to recognize them and institutionalize utility services, what the hidden costs and unintended consequences are of becoming formal end users of state systems. The dissertation provides an overview of the forces at work in shaping Cairo, highlighting the rural to urban migration patterns and shifting urban policy over the course of the 20th century that have funneled so many into informal housing settlements. In addition, the dissertation highlights the particular material history of Ezbet Khairallah, and how that has shaped the social and material circumstances of residents. It examines the material and affective implications of being unable to escape waste, of bodies that bear signs of systems that both make life possible and make life difficult. By studying the institutional framework in which these questions get worked out in Egypt, we can better situate the struggles of those living in the urban margins of the global south, such as those in Ezbet Khairallah.Item Case Studies on the Effects of Climate Change on Water, Livestock and Hurricanes(2014-07-25) Yu, Chin-HsienThis dissertation investigates the agricultural impacts of climate change in three ways addressing water implications of mitigation strategies, feedlot livestock productivity vulnerability induced by climate change and dust and welfare effects of altered tropical storm frequency and intensity. Even though mitigation alleviates GHG emissions and ultimate climate change, it also has externalities and can alter water quantity and quality. The first essay focuses on examining the water quality and quantity effects of mitigation strategies. This is done using quantile regression and sector modeling. The quantile regression result examined land use change and showed that an increase in grassland significantly decreases water yield with changes in forest land having mixed effects. In the sector modeling we find that water quality is degraded under most mitigation alternatives when carbon prices are low but is improved with higher carbon prices. Also water quantity slightly increases under lower carbon prices but significantly decreases under higher carbon prices. The second essay examines the effects of climate change and dust on feedlot cattle performance plus the benefits of dust control adaption. A linear panel data model is used to see the relationship between climate and dust with cattle sale weight. We find that hotter temperatures and increased dust levels generally worsen cattle live sale weight. Dynamic programming is then used to estimate the benefits of dust control. The results show that dust control activity is beneficial. Additionally, climate change is found to be damaging and a factor that reduces dust control benefits. The last essay applies a demand model to investigate the economic consequences of tropical storm strikes on the vegetable market in Taiwan. Findings are that tropical storm strikes raise vegetable prices and in turn cause consumer loss and producer gain. Also higher intensity storms generally have larger impacts than lower intensity storms. Finally possible climate change induced intensified tropical storms or increased storm frequencies were found to result in a more severe welfare loss.Item Characterizing the energy transfer from a thermite reaction to a target(2007-12) Burkhard, Jonathan N.; Pantoya, Michelle; James, Darryl; Berg, Jordan M.Nano-sized materials often have novel properties that drastically improve performance. Very few studies on the nano-aluminum and water combustion reaction have been done without the addition of a gelling agent. The depth at which gas fueled underwater cutting torches can be used is limited by their fuel gas storage pressure restrictions. Using a nano-aluminum and water thermite reaction as the fuel for an underwater cutting torch eliminates depth limitations and creates a unique opportunity to use ambient water from the surrounding environment as the oxidizer for the reaction. Reaction characteristics were studied with high speed video analysis in inert and oxidizing environments. The heat transfer characteristics of the nano-aluminum and water reaction were compared to baseline methylacetylene-propadiene and propane fueled torches by collecting temperature data on metal test plates with thermocouples and a high speed infrared camera. Additives, such as Teflon powder, were mixed with the original thermite reactants to improve heat transfer to the test plates from the reaction. High speed video data showed that flame propagation rates were not significantly affected by the environment surrounding the reaction. Differential scanning calorimeter data confirmed that the aluminum was reacting efficiently. Temperature data from the test plates was compared after 0.9 s of heating. Thermocouple data confirms infrared camera temperature measurements. The MAPP gas torch, propane torch, Al/water reaction, and Al/water/Teflon reaction heated the plates at an average rate of 29.3 ± 0.2, 23.1 ± 0.2, 54 ± 3, and 38 ± 1 K/s respectively. The temperature change per mass of fuel burned was calculated for each torch and reaction as 400 ± 200, 500 ± 200, 180 ± 60, and 130 ± 30 K/g respectively. The time required to reach the oxidation temperature of steel for each torch and reaction was 40 ± 20, 50 ± 30, 21 ± 9, and 30 ± 10 seconds respectively. This study concludes that the Al/water reaction could significantly improve an underwater cutting device because surrounding water could be used as the primary oxidizer, the reaction has a higher heating rate than gas fuels, and the usable depth is not limited by fuel storage pressures.Item City of mountains : Denver and the Mountain West(2012-12) Busch, Eric Terje; Brands, H. W.; Bsumek, Erika M; Hoelscher, Steven D; Stoff, Michael B; Zamora, EmilioThis study is an urban history of Denver, Colorado, viewed through the lens of its constantly evolving physical, political, cultural and economic relationship with its mountain hinterland. From the town's early years as a 19th century mining and ranching depot to its 20th century emergence as a hub of tourism and technology, that relationship informs every aspect of the city's urban, cultural and environmental history. This study seeks, first, to analyze Denver's historical appropriation and utilization of its mountain hinterland, whether for water, wealth, recreation and cultural identity. Second, it highlights how access to and control over the Rocky Mountain hinterland shaped Denver's evolving political, class and racial landscapes throughout the city's history. Integrating the methodologies of environmental, urban, and social history, it demonstrates how different social groups competed for access, control, and the ability to vii assign value to the mountain hinterland. Every Denverite in the city's history, regardless of station, has lived within the context of this tense and constantly changing relationship. Since the city's founding, that relationship has been the constant object of human agency, accommodation, and change, and in it can be read the story of Denver itself.Item Classification of playa lakes based on origin, morphology, and water quality parameters(Texas Tech University, 1995-05) Casula, KavithaPrevious playa lake studies on the Southern High Plains (SHP) were conducted to undCTstand the origin, development, hydrology, and habitat value of playa lakes, with limited work done on the water quality aspects. The few water quality studies were in the form of analyses of samples from a few playa lakes. Results of sample analyses from a few lakes in a particular region were used to geneialize the water quality of nearly 30,000 lakes on the SHP. However, such generalization is not an adequate measure of the water quality variations of lakes OVCT the wide expanse of the SHP (80,000 km^). Hence, models are needed which can predict water quality based on lake specific parameters (such as morphological variables) without performing extensive analyses of field samples. The first objective of this study, therefore, is to initiate development of such mathematical models for wata* quality variables of playa lakes. During the process of model development, water quality variables from 62 lakes distributed over eleven counties were used. The second objective of this study is to use the values of morphological variables (given by Reeves) in the water quality models developed in the first phase. Consequently, a possible range for the water quality variables of the three types of lakes (characterized by Reeves) can be proposed. With respect to the first objective, strong water quality models could not be developed with the set of lake specific parameters used. Since, strong models could not be developed and validated a possible range for the water quality variables could not be proposed.Item Conservation engineering and agricultural terracing in Tlaxcala, Mexico(2014-05) LaFevor, Matthew Cole; Doolittle, William EmeryThis research examines the practice of hillslope terracing in the state of Tlaxcala, Mexico. It explores how one popular terrace form, zanja-bordo (ditch-and-border) terraces, is employed in two distinct, though sometimes related contexts: (1) producing crops (agriculture) and (2) protecting natural resources (conservation). It first traces the use of zanja-bordo terraces in traditional agriculture in the region, highlighting some of the major elements of their form and function, issues surrounding their antiquity, and their possible role in the landscape degradation so prevalent in the region today. Moving from this agricultural context, the dissertation next examines the role of zanja-bordo terraces in landscape restoration efforts in Tlaxcala. It demonstrates the key role that active and prolonged maintenance plays in long-term efforts to restore previously degraded farmland back to productive capacity. The dissertation then examines more broadly how government programs to promote zanja-bordo terracing in the region impact farmers, whose ancestors have been building zanja-bordo terraces for centuries. Findings from the collection, synthesis, analysis, and groundtruthing of written data on governmental terracing projects in the state reveal that while perhaps well intentioned, these programs did little to promote sustainable agricultural development or environmental conservation in the region. Finally, the dissertation moves above the 3,000-meter mark to examine the relatively recent phenomenon of high-elevation terracing in Mexico's national parks. Conceived as a means of erosion mitigation, water conservation, reforestation, and even fire suppression, government agencies now construct zanja-bordo terraces throughout the understory of many of Mexico's subalpine forests. A case study of the la Malinche (Malintzi or Matlalcueyatl) National Protected Area illustrates some of the difficulties in examining each of the claimed benefits of terracing in these environments. Whether for agriculture or restoration, as a techno-developmental strategy, or as a tool for soil and water conservation, zanja-bordo terraces are shown to be an adaptable and effective hillslope management technology. This dissertation demonstrates, however, that successful adaptation and implementation of zanja-bordo technologies into different contexts largely depends on the effective planning, monitoring, and maintenance of terrace structures and processes. Ultimately, the sustainability of zanja-bordo terracing relates more to issues of contextualization and human motivation than to questions of technological innovation.Item Constructed wetlands for agricultural wastewater treatment(Texas Tech University, 1998-08) Ancell, Michael EdwardA 23-tank, 43 m , pilot-scale constructed wetland system was loaded daily with 136.2 liters of cattle feedlot wastewater to measure the nitrogen removal effectiveness and to compare this removal to nitrogen removal models. The 23-tanks were separated into six different treatment series, and the effects of four different total nitrogen (TN) loading rates were investigated with three different series surface areas and detention times. The four TN loading rates were 11.4, 8.0, 2.3, and 0.5 g TN/day. All four loading rates were tested in treatment series consisting of four tanks. Additionally, the 2.3 g TN/day loading rate was tested in a series with two tanks and a series with five tanks. The removal of nitrogen constituents from wastewater is dominated by maximizing the permanent removal processes inherent to the nitrogen cycle. Although the nitrogen cycle is a complex interaction of biological and chemical phenomena, maximizing its inherent removal processes is attainable in the wetland environment. The primary facilitator of this nitrogen removal is the root-zone aeration of the predominantly anaerobic environment surrounding the wetland soil. Given proper amounts of dissolved oxygen, the microbiota of nitrification can oxidize ammonia to nitrate, and denitrification can take place in the anaerobic environment, ultimately removing nitrogen from the wastewater in the form of nitrogen gas. An additional permanent nitrogen removal pathway in wetlands is defined by the plant uptake of ammonia and/or nitrate. However, maximizing this removal pathway requires plant harvesting, which can be costly in the full scale wetland treatment settmg and does not always yield an appreciable amount of nitrogen removal.Item Design and control of an integrated wind-water desalination system for an inland municipality(Texas Tech University, 2008-08) Noll, Dennis D.; Ewing, Bradley T.; Song, Lianfa; Swift, Andrew H. P.; Chapman, Jamie C.Current water pricing standards do not take economic responsibility for dwindling potable water aquifer resources. By only incorporating financial, but not true economic costs of these scarce resources, serious depletion of these often slow-recharging groundwater resources has occurred in many areas in the United States. Aquifer depletion for some areas looms on a 50-year or closer horizon, and many municipalities in the Southwest and elsewhere face potential distress due to lack of sustainable fresh water availability. In order for these cities to remain economically and physically viable, alternative water resources must be found. An affected West Texas inland municipality will become the subject of research to evaluate the technology and economics of a full-scale, integrated, wind-powered reverse osmosis water purification system. The integrated system will be applied to produce potable water from a brackish aquifer using renewable energy to reduce the energy costs of the system. An adaptive and intelligent control algorithm will control the integrated wind-water system. The algorithm will process streaming real-time water use and electrical demand data in combination with wind speed measurements in order to determine the best use of the energy produced by a turbine array: either for water purification or for displacing conventional power on other municipal loads. The end product of this system is a water purification process that will utilize a brackish water aquifer for all of the city‘s potable water needs, and wind energy for all associated pumping, reverse osmosis, distribution and other electrical loads.Item Diffusion of Innovation: The Introduction of a Point-Of-Use Ceramic Water Filter to South Texas Colonia ResidentsBuentello, Sara A.; Kilburn, John C.People living in South Texas colonias continue to face developing world living conditions. Many residents of the colonias still live without basic and fundamental utilities including running water in their homes. Worldwide lack of access to clean running water is a major social problem and found in new colonias. Research has found that point-of-use ceramic water filters (CWFs) are a viable and cost effective way to purify water and developing countries throughout the world use them today. This study employs Everett Rogers’s 1964 Diffusion of Innovation Theory. Rogers’s theory has been applied in countless studies to analyze the processes through which communities adopt new technologies or practices. One adoption technology, CWFs are made by a facility in the general area in which the residents interviewed for this study live. Results found that residents were interested in the CWF but had not been introduced to the filter and were unaware that a filter making facility was near their homes. While the focus of this study was to determine whether residents would adopt CWF technology, what came into question was why the innovation had not diffused. Research has found that a major reason attributed to a failure to diffuse is that outreach services do not rapidly adapt to the creation of new colonia residents through contact and education about the water filter. Potential adopters did show interest in the CWF when its use was explained as a part of this study. State and local resources need to be deployed to prevent communication of water-borne diseases and preserve new colonia resident’s health.Item Effects of hydroperiods on plant growth and water quality in constructed wetlands(Texas Tech University, 2002-05) White, Troy L.Three experiments were conducted to determine the effects of hydroperiod on plant growth and water quality in wetiands constructed for treatment of agricultural wastewater. Paspalum distichum (knot grass), Typha latifolia (cattails), and Eichhomia crassipes (water hyacinth) specimens were subjected to variable hydroperiod loading regimes and monitored for survival rate and biomass productivity. Test scale knot grass treatment wetlands were subjected to variable hydroperiod regimes and monitored for biomass productivity and water quality improvements. Effective treatment cell length and fate of nitrogen were determined through examination of influent versus effluent total nitrogen, biomass production, plant nitrogen assimilation, and soil nitrogen accumulation as a function of distance down the cells. The fate of total nitrogen (TN) in the system was examined in an evaluation of the mass balance of total nitrogen throughout the systems. Variable hydroperiods examined ranged from 1 day wet and 1 day dry to 28 days wet and 14 days dry. Continuously flooded control systems were also examined. Total nitrogen loading rates in the systems ranged from 30 to 45 mg/1. In experiments conducted to monitor water quality and fate of nitrogen, hydraulic loading rates were maintained to achieve 2 day hydraulic retention times in the treatment cells. The test scale wetiand system was comprised of 21, 3.15 m long x 0.31 m wide x .31 m deep cells, which could be independently loaded and drained.Item Emulsions and microemulsions of water and carbon dioxide: novel surfactants and stabilization mechanisms(2005) Ryoo, Won Sun; Johnston, Keith P., 1955-Item Energy transitions on the Hawaiian Islands : water resources implications for Hawaii's electrical power system(2014-08) Dawes, Colleen Marie; Pierce, Suzanne Alise, 1969-; King, Carey; Beach, FredImported fossil fuels currently supply over 90% of the Hawaiian Islands' annual consumed electricity, the majority of which is produced by petroleum-fired power plants. The state of Hawaii has a goal to dramatically reduce this reliance on imports and achieve 30% locally sourced, renewable power use by 2030. This goal signals an energy transition for the state that is achievable through decommissioning, repurposing and new development in power generating technologies and infrastructure. In addition to dependencies on imports and fossil fuels, Hawaii's electrical industry is also currently the largest water user in the state of Hawaii with over 75% of all surface water and groundwater withdrawals attributed to thermoelectric generation and cooling. Transitions in Hawaii's fuel mix from a petroleum dominant mix to renewable fuel for power generation could have significant impacts on water use and availability: a small change in energy resources could mean significant changes in water use. Integrated planning and management for these two resources is needed. A successful energy transition for Hawaii in the next 15 years will involve precise planning, and strategic decision-making for both energy and water. This research adopts a systems view to evaluate energy-water interdependencies within Hawaii's electrical system, comparing the current fuel mix and projections for energy trends on the islands with the continental United States. A power plant database built from Hawaii-specific utility-scale data combined with national averages for thermoelectric water use reported in the literature provide an overview of Hawaii’s current electrical sector and its water use. This snapshot identifies critical resource management needs and reveals disparities between the electrically detached islands. Scenario analysis of projected change in Hawaii’s electrical sector is used to assess the implications for water use intensity across a range of locally sourced power capacity and generation options. Results indicate that, because it displaces petroleum power production, increases in renewable energies on Hawaii will produce substantial water savings, especially in total operational water withdrawals.Item The energy-water nexus : an examination of the water quality impacts of biofuels(2010-05) Twomey, Kelly Marie; Webber, Michael E., 1971-; Lawler, Desmond F.Water and energy share an important relationship since it takes water to produce energy, and likewise, energy to pump, treat, and distribute water. This thesis explores the energy-water nexus in regards to electricity and transportation fuel production, as well as water treatment. It investigates how the Energy Independence and Security Act of 2007 might affect this interrelationship in the future since increases in corn cultivation for biofuels production are likely to lead to higher nitrate concentrations in US water reservoirs, which could trigger the requirement for additional energy consumption for drinking water treatment. The analysis indicates that advanced drinking water treatment might require an additional 2360 million kWh annually to treat drinking water currently exceeding the Environmental Protection Agency’s maximum contaminant level (MCL) limit of 10 mg per liter of nitrate-nitrogen. This is a 2100% increase in energy consumption for advanced water treatment to meet this MCL in comparison with surface water treatment alone. Although results indicate that most large surface and groundwater drinking water resources are not likely to exceed safe drinking water standards due to the expansion of corn-starch based ethanol production, smaller water reservoirs in agricultural regions are susceptible to nitrate contamination in the future. Consequently, these sources might require energy-intensive drinking water treatment to reduce nitrate levels below 10 mg per liter of nitrate-nitrogen. Based on these results, I conclude that projected increases in nitrate contamination in water may impact the energy consumed in the water treatment sector, because of the convergence of several related trends: (1) increasing cornstarch-based ethanol production, (2) increasing nutrient loading in surface water and groundwater resources as a consequence of increased corn-based ethanol production, (3) additional drinking water sources that exceed the MCL for nitrate, and (4) potentially more stringent drinking water standards for nitrate.Item The energy-water nexus : energetic analysis of water and wastewater treatment, distribution and collection(2014-12) Kjellsson, Jill Blosk; Webber, Michael E., 1971-The water sector is responsible for a significant portion of energy use. Energy is required for water treatment, water distribution, wastewater collection and wastewater treatment. There is significant benefit to water utilities that can be gained by understanding how much energy, what type of energy, and at what time of day energy is being used. The Austin Water Utility (AWU) is a useful testbed for examining the energy use for each specific step of the process due to the availability of data and the fact that the majority of Texas (both in terms of population and land area) is serviced by a single electric grid. This research examines the type and quantity of energy used by AWU. From an electricity supply perspective, electric utilities work year round to ensure that there is enough electricity in their generation portfolios to meet the high loads that their customers demand, and to assure that the electric distribution grid is capable of providing the transmission requirements of that electricity. System peak demand is the largest amount of electricity consumed by a utility's customers at any given time. Therefore electric utilities, such as Austin Energy, create and market their energy efficiency programs to help reduce this peak and avoid the need to build new generation capacity which can be expensive. Because AWU is one of Austin Energy's largest customers, AWU's ability to shift its energy use from on-peak to mid-peak and off-peak time periods can contribute towards reducing the peak, and can help avoid the need for new generation capacity. This analysis finds that AWU can reduce its electricity demand during peak periods by making use of reservoir capacity, i.e. by filling its reservoirs prior to peak time and draining them during peak periods. This proposed pumping schedule could save AWU up to 29% of its monthly electricity costs under current Austin Energy time-of-use rate (as opposed to flat rate) structures at the specific pump station analyzed as part of this research. Together, state-wide water utilities provide even more opportunities for the interconnected Electric Reliability Council of Texas' (ERCOTs) grid that are also evaluated in this research.Item Energy-water nexus in Texas(2010-05) Stillwell, Ashlynn Suzanne; Webber, Michael E., 1971-; Lawler, Desmond F.Energy and water are closely related to each other, yet management of the two resources has historically been independent. Water resources planning and management often ignores increases in energy consumption in response to securing drinking water supplies. At the same time, policies concerning power generation, including emission of greenhouse gases, can dramatically increase water consumption for electricity. As a result, tradeoffs often exist between energy and water resources policies. This work collectively describes and analyzes the nexus of energy and water within the state of Texas, with some extension to the rest of the United States. By aggregating Texas-specific data and national average values reported in literature, a snapshot of the energy-water nexus in Texas is presented, showing water use for thermoelectric power generation and electricity use for water and wastewater systems. Case studies then illustrate the energy and water implications of five policy and resource management scenarios: 1) statewide implementation of municipal water conservation and reuse, 2) installation of alternative thermoelectric cooling technologies to mitigate water scarcity, 3) use of desalination and long-haul water transfer as a drinking water supply for Dallas, Texas, 4) integration of wind power with brackish groundwater desalination as a water supply, and 5) energy recovery from municipal wastewater treatment plants. These analyses combine to reveal the intricacies of the energy-water nexus in Texas and its implications for future resource management.