825 research outputs found
Evaluation of power generation operations in response to changes in surface water reservoir storage
We used a customized, river basin-based model of surface water rights to evaluate the response
of power plants to drought via simulated changes in reservoir storage. Our methodology
models surface water rights in 11 river basins in Texas using five cases: (1) storage decrease of
existing capacity of 10%, (2) storage decrease of 50%, (3) complete elimination of storage,
(4) storage increase of 10% (all at existing locations), and (5) construction of new reservoirs
(at new locations) with a total increase in baseline reservoir capacity for power plant cooling
of 9%. Using the Brazos River basin as a sample, we evaluated power generation operations in
terms of reliability, resiliency, and vulnerability. As simulated water storage decreases,
reliability generally decreases and resiliency and vulnerability remain relatively constant. All
three metrics remain relatively constant with increasing reservoir storage, with the exception
of one power plant. As reservoir storage changes at power plants, other water users in the
basin are also affected. In general, decreasing water storage is beneficial to other water users
in the basin, and increasing storage is detrimental for many other users. Our analysis reveals
basin-wide and individual power plant-level impacts of changing reservoir storage,
demonstrating a methodology for evaluation of the sustainability and feasibility of
constructing new reservoir storage as a water and energy management approach.Mechanical Engineerin
Nontraditional Jobs Case Study
A case study of nontraditional job training programs for women with lessons learned and recommendations for the field
Swimming Without Fear: Equitable Instruction
A qualitative single-subject exploratory case study approach was used to examine the effectiveness of an intervention process to assist a 30-year-old female in reducing her fear of water. During the 18-week intervention, systematic desensitization was utilized in conjunction with multiple data sources to determine its success. Data sources included the Spielberger State-Trait Anxiety Inventory (STAI), semi-structured interviews, swimming skills tests, collages, and participant and researcher journals. Data analysis examined changes in scores for the STAI and swimming skills tests while an inductive data analytic strategy was applied to organize and make sense of the interviews, collages, and participant journal entries. A researcher’s journal was kept confirming major findings. Results showed a decrease in fear as documented by interviews, participant journal entries, and the post-collage. No differences in scores were noted for the STAI and swimming skills tests. These findings suggest that cognitive and psychological progress was made by the participant; however, more time was needed to transform this progress into performing physical skills in the water
Implementation of Brackish Groundwater Desalination Using Wind-Generated Electricity: A Case Study of the Energy-Water Nexus in Texas
Growing populations and periodic drought conditions have exacerbated water stress in many areas worldwide. In response, some municipalities have considered desalination of saline water as a freshwater supply. Unfortunately, desalination requires a sizeable energy investment. However, renewable energy technologies can be paired with desalination to mitigate concern over the environmental impacts of increased energy use. At the same time, desalination can be operated in an intermittent way to match the variable availability of renewable resources. Integrating wind power and brackish groundwater desalination generates a high-value product (drinking water) from low-value resources (saline water and wind power without storage). This paper presents a geographically-resolved performance and economic method that estimates the energy requirements and profitability of an integrated wind-powered reverse osmosis facility treating brackish groundwater. It is based on a model that incorporates prevailing natural and market conditions such as average wind speeds, total dissolved solids content, brackish well depth, desalination treatment capacity, capital and operation costs of wind and desalination facilities, brine disposal costs, and electricity and water prices into its calculation. The model is illustrated using conditions in Texas (where there are counties with significant co-location of wind and brackish water resources). Results from this case study indicate that integrating wind turbines and brackish water reverse osmosis (BWRO) systems is economically favorable in a few municipal locations in West TexasMechanical Engineerin
A Review of Energy-for-water Data in Energy-water Nexus Publications
Published literature on the energy-water nexus continues to increase, yet much of the supporting data, particularly regarding energy-for-water, remains obscure or inaccessible. We perform a systematic review of literature that describes the primary energy and electricity demands for drinking water and wastewater systems in urban environments. This review provides an analysis of the underlying data and other properties of over 170 published studies by systematically creating metadata on each study. Over 45% of the evaluated studies utilized primary data sources (data collected directly from utilities), potentially enabling large-scale data sharing and a more comprehensive understanding of global water-related energy demand. The most prevalent geographic scale of the existing literature was at the individual city scale (39%), limiting comparisons between utilities. Additionally, energy-for-water studies span 34 different countries with 11 countries having at least 4 published studies. The analyzed literature often considered greenhouse gas emissions of energy demand as an important input for life cycle analysis, highlighting the broader impact of the energy-water nexus. As a result of the review, we identify several common practices for filling data gaps, discover that research and data are primarily concentrated in three countries (Australia, China, and the United States), and offer suggestions for the future of the energy-water nexus, specifically regarding energy-for-water
Where does solar-aided seawater desalination make sense? A method for identifying sustainable sites
AbstractGlobal water planners are increasingly considering seawater desalination as an alternative to traditional freshwater supplies. Since desalination is both expensive and energy intensive, taking advantage of favorable natural and societal conditions while siting desalination facilities can provide significant financial and environmental returns. Currently, policy makers do not use a location-specific integrated analytical framework to determine where natural and societal conditions are conducive to desalination. This analysis seeks to fill that gap by demonstrating a multi-criteria, geographically-resolved methodology for identifying suitable regions for desalination infrastructure where 1) available renewable resources can offset part of the fossil energy load; 2) feedwater characteristics reduce the total energy needed for desalination; and 3) human populations have capacity and willingness to pay for desalinated water. This work demonstrates the method with a quantitative global analysis that identifies favorable sites for solar-aided seawater reverse osmosis desalination (SWRO) based on specific target criteria. Location-based data about natural conditions (solar insolation, ocean salinity, and ocean temperature) are integrated and mapped with social indicators (water stress, prevailing water prices, and population) to identify regions where solar-aided SWRO has the highest potential. This work concludes that water-stressed tropical and subtropical cities show the highest potential for economically sustainable solar-aided SWRO
Quantum Mechanics on the h-deformed Quantum Plane
We find the covariant deformed Heisenberg algebra and the Laplace-Beltrami
operator on the extended -deformed quantum plane and solve the Schr\"odinger
equations explicitly for some physical systems on the quantum plane. In the
commutative limit the behaviour of a quantum particle on the quantum plane
becomes that of the quantum particle on the Poincar\'e half-plane, a surface of
constant negative Gaussian curvature. We show the bound state energy spectra
for particles under specific potentials depend explicitly on the deformation
parameter . Moreover, it is shown that bound states can survive on the
quantum plane in a limiting case where bound states on the Poincar\'e
half-plane disappear.Comment: 16pages, Latex2e, Abstract and section 4 have been revise
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