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Data-Driven Techno-Economic Analysis, Optimization, And Uncertainty Quantification of Integrated Energy Systems in Deregulated Electricity Markets
Get PDFElectricity is a ubiquitous energy source in daily life, powering everything from stovetops and cellphones to vehicles and industrial processes. While wind and solar power have become increasingly common sources of electricity, the majority of electricity is still produced by burning fossil fuels, releasing greenhouse gases and propelling climate change. Wind and solar power cannot economically replace these fossil fuel energy sources on their own because they do not produce consistent power; the wind must be blowing, and the sun must be shining for them to make electricity. Nuclear power is a reliable source of energy that does not generate greenhouse gases when generating electricity but is not flexible enough to directly replace existing traditional generators. Pairing these nuclear power plants with energy storage technologies like “thermal batteries” could help them find this needed flexibility, but the economics of these plants are not well-understood. In particular, there is significant uncertainty in construction costs, operating costs, and what revenue these plants would bring in. This dissertation first puts a number to these uncertainties. While the construction costs for advanced nuclear power plants are the greatest source of uncertainty, the uncertainty in revenue is also significant for some markets, and many past studies have not considered this source of uncertainty. One way to measure the effect of variation in quantities which change over time like the electricity demand, renewable energy production, and electricity price is to use a statistical model that describes how these values change over time, then use that model to create many scenarios over which the energy system can be modeled. Previous studies have used models which are either not very well suited for modeling these quantities or use models which are not interpretable. Both having realistic scenarios and having an understanding of how these values relate to each other over time is important for understanding the electricity markets that energy systems operate in. Neural stochastic differential equations are used for the first time in energy systems studies for this purpose in this dissertation, and they are shown to perform comparably to state-of-the-art machine learning models while being more interpretable. The neural stochastic differential equation model developed here is used to optimize a nuclear power plant with thermal energy storage in the ERCOT market in Texas, which was the most sensitive to time series uncertainty of the markets considered earlier. A neural network model is used to estimate the price of electricity from the electricity demand, renewable energy generation, the amount of each type of generator in the market, and the price of natural gas, and this model is used to estimate how much the flexible nuclear plant will decrease the price of electricity and therefore the plant revenue. This analysis is performed for various cases of plant price and system sizes. The energy storage system makes the plant more profitable in almost all cases, but no benefit was seen for very expensive plants in small markets. This shows that adding energy storage to make nuclear power plants more flexible can make them more cost-competitive in electricity markets in many cases, though this should be evaluated on a market-by-market behavior
A Home Dyer\u27s Garden, Part II: Extracting Pigment From Japanese Indigo
Get PDFSeveral indigo dyeing methods use powdered pigment. This fact sheet outlines a simple, inexpensive method of extracting the pigment from plants. For information on growing Japanese indigo or dyeing with plant and pigment, see the other fact sheets in the Utah State University (USU) Extension series A Home Dyer’s Garden, including Part I: Growing Japanese Indigo and Part III: Dyeing With Japanese Indigo
Curriculum Subcomittee Minutes December 5, 2024
Get PDFApproval of Minutes Program Proposals Semester Course Approval Reviews Other Business Adjourn: 3:02p
Function Over Form: The Benefits of Aspen as Surrogate Brood-Rearing Habitat for Greater Sage-Grouse
Get PDFSpecies of conservation concern are often habitat specialists, posing significant risk to those species when specific plant communities are threatened. As a result, practitioners habitually focus conservation efforts on these communities while ignoring ecological mechanisms that explain the wildlife–plant relationships. In doing so, practitioners may overlook alternative vegetation communities that could maintain wildlife populations under alternative conditions (e.g., climate change). Here, we term these areas surrogate habitat, defined as vegetation communities or resource sites that provide similar critical resources as conventional sites, and assess their potential for conservation using a case study of greater sage-grouse (Centrocercus urophasianus) on Parker Mountain, Utah (1998–2009). Sage-grouse are a sagebrush-obligate species and a species of conservation concern. Range-wide conservation efforts have long emphasized management of seasonal habitats within semiarid sagebrush ecosystems, specifically management of mesic or wet meadow sites that provide brood-rearing habitat required for population persistence. Despite this requirement, no conventional mesic habitat exists on Parker Mountain, yet is supports one of Utah\u27s largest sage-grouse populations. Rather, the Parker sagebrush system abuts quaking aspen (Populus tremuloides) stands that may provide brood-rearing habitat analogous to wet meadow sites. It is unclear, however, to what extent sage-grouse use these aspen stands because sage-grouse commonly avoid tall structures (e.g., trees) and their associated avian predators. Thus, we tested whether (1) sage-grouse selected for surrogate habitat (i.e., aspen edge) and (2) selection behaviors related to surrogate habitat had demographic effects on the population. As we predicted, sage-grouse selected for these areas, and the sage-grouse that spent increased time closer to aspen edges did not experience increased mortality. Together, this demonstrates that the aspen–sagebrush edge provided a surrogate for the wet meadows used by other populations. More broadly, this suggests that conservation practitioners should move beyond simplistic wildlife-habit associations toward a more holistic view of animal ecology focused on the wildlife–resource association, an approach that becomes particularly useful in areas where conventional obligate habitat may be degraded or lost. This work also implores us to examine alternative habitat potential rather than applying one-size-fits-all models to threatened species conservation
Multi-Decadal Aspen Dynamics Show Recruitment Bottleneck Across Complex Mountain Community
Get PDFChanges in forest structure and shifts in tree species composition have occurred globally due to climate change and altered disturbance regimes. With climate trending toward warmer and drier conditions, these altered forest communities may reorganize in diverse and unpredictable ways. This is especially true in mountain environments where a range of vegetation types and abiotic conditions coexist. In this study, we used long-term permanent plot data from a site spanning broad environmental gradients to assess regeneration and mortality patterns in populations of aspen (Populus tremuloides). The study site, located on the San Francisco Peaks, Arizona, USA, is near the hot, dry edge of the species\u27 range and has experienced compounding pressure from extreme drought, chronic ungulate browsing, and wildfire in the past two decades. Over a 20-year study period, spanning one of the most prolonged drought periods in at least 1200 years, aspen overstory mortality averaged 42% and was most common in smaller, younger trees and at lower elevations. Aspen regeneration density increased 13% and was found in a greater proportion of study sites. However, we observed a noticeable lack of stems in the tallest regeneration size class ( \u3e200 cm) and the smaller tree size class (2.5–15cm in diameter), potentially indicating a demographic bottleneck whereby few trees are recruiting into the overstory. Likewise, prolific aspen suckering occurred after a 2001 wildfire, although regeneration density eventually decreased to pre-fire levels, with \u3c 1% of individuals reaching heights \u3e 200cm. Aspen regeneration densities showed the greatest increases in cool, wet sites and beneath open forest canopies. Disturbances function as catalysts for aspen regeneration, but persistence of aspen stands depends on recruitment of stems into overstory size classes, a process that is limited, particularly on lower and more exposed sites
Atmospheric Waves Experiment (AWE) Advanced Mesopheric Temperature Mapper (AMTM) Optomechanical Design, Fabrication, and Environmental Test
Get PDFThe AWE AMTM is a widefield of view (WFOV) infrared imaging radiometer designed for use in measuring the P1(2) and P1(4) emission lines of the earth’s OH layer to determine temperature and produce images of gravity waves. The sensor was designed, built, and characterized by Utah State University (USU) Space Dynamics Laboratory (SDL) and has been externally mounted to the International Space Station (ISS) looking nadir to collect images for analysis for a minimum of two years. The Opto-Mechanical Assembly (OMA) consists of four identical imaging telescopes, each comprised of a fisheye lens, a field lens, and a re-imager lens and share a common filter wheel with four narrow band filters. The sixteen lenses in each telescope are coaligned and bonded into five stress stabilized aluminum lens barrels. Precision machining allowed the barrels to be mated together via mechanical tolerances (i.e., snap-to-fit) to form the fore and aft assemblies of each telescope that mount to the front and rear of a common, central tombstone assembly which houses the filter wheel mechanism. The detectors were aligned, supported, and thermally compensated via a titanium thermal compensator and custom focus shim attached to the aft end of each telescope. Following assembly, the OMA was environmentally tested including EMI/EMC, vibration, and thermal cycling. Prior to and following each environmental test, the point response function of each telescope was measured and compared to verify performance. This paper will present an overview of the design, fabrication, assembly, integration, and environmental testing of the OMA
ACT for OCD: An Example of ACT and Values-Based Exposures
No full textExposure exercises as seen in cognitive behavioral therapy (CBT) and exposure and response prevention (ERP) are standard in the treatment of obsessive-compulsive disorder (OCD). In the last two decades, additional research has been conducted on acceptance and commitment therapy (ACT) and the ways that exposure exercises are conducted from an ACT model. Empirical support for conducting exposures from an ACT model exists. Group level statistics suggest that ACT with ACT-based exposures is as effective as traditional ERP or CBT. A key component of ACT and values-based exposures is the focus on teaching psychological flexibility to allow for engagement with values-based exposures. In this case study, we present an adult woman with OCD who completed 24 sessions of ACT+ values-based exposures. Client scores on the Y-BOCS decreased from severe levels to mild-moderate levels through treatment. Additionally, the client was more actively engaged in her life and reported greater quality of life at the conclusion of treatment. The goal of this case study is to demonstrate how values-based exposures can be used in the treatment of OCD
Faculty Senate Agenda October 7, 2024
Get PDF3:00 Call to Order Approval of Minutes 3:05 University Business 3:20 Faculty Senate Business 3:35 Information EPC Report Human Resources Policies 330 & 392 3:55 Report Educational Policies Committee Annual Report Honors Annual Report 4:05 Old Business 4:10 New Business Adjourn: 4:30 p
Nursery Cultural Practices Influence Morphological and Physiological Aspen Seedling Traits: Implications for Post-Fire Restoration
Get PDFAspen forests are threatened by the impacts of a changing climate and are showing large-scale mortality with meager natural regeneration to restore these loses. Therefore, there is an increasing demand for high-quality aspen seedlings to assist with forest restoration efforts. Nursery cultural practices can be used to alter aspen seedling traits to improve adaptability to dry planting conditions. In this study, the effects of container size (SC10 and D30; 158 and 590 mL, respectively) and nursery irrigation treatment (high and low irrigation; 90% and 70% container capacity, respectively) on seedling growth and a suite of morphological and physiological traits were investigated. The combination of large container size and low irrigation treatment resulted in seedlings with lowest height-to-diameter ratio and specific leaf area, which are desired traits for seedling performance on dry sites. Additionally, seedlings exposed to low irrigation conditions at the nursery stage had a lower (more negative) osmotic potential at full turgor, suggesting a higher likelihood of drought tolerance. Overall results from this study provide insight into utilizing nursery cultural practices to produce seedlings with target characteristics that may ultimately lead to establishment on harsh, dry planting sites in large-scale reforestation projects
Sunrise Propulsion Subsystem Leak Rate Measurement Methodology
Get PDFAs part of the integration and testing for Sun Radio Interferometer Space Experiment (SunRISE), it was necessary to characterize the propellent leak rate of the fully assembled propulsion subsystem for each satellite to ensure compliance with performance requirements. SunRISE utilized a cold gas system for its propulsion subsystem, using R-236fa propellant inside a tank made from a monolithic 3D printed SLA material. It was not possible to accurately characterize the propellent leak rate via weight by measuring the mass loss from the tank. This is due to the SLA material having both a high absorbance rate of water in normal atmospheric conditions and a high outgassing rate of water when under vacuum. However, by measuring the rate of change in the partial pressure of the R-236fa via a Residual Gas Analyzer (RGA) in a rate-of-rise test under vacuum and taking the time derivative of the ideal gas law, / = / ( ∙ / ) = / ∙ / , the leak rate could be calculated. This method proved to be efficient and effective in verifying that the fully assembled propulsion subsystem for each satellite met the leak rate requirement