Browsing by Department "Energy and Earth Resources"
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Item 24x7 load matching with wind, solar photovoltaic, and battery storage power plants(2020-06-29) Sauer, Jennifer Ellen; Butler, John C. (Clinical associate professor)Corporations and cities with decarbonization targets have to date accounted for green energy achievements by offsetting fossil-fuel power consumption with renewable energy certificates (RECs) on annual region-agnostic bases. In 2018 Google pronounced the decarbonization and risk management benefits of procuring time-matched regionally generated zero-carbon energy with consumption, asserting that the pathway toward deep decarbonization of the grid will require solutions that ensure low-cost power at all times across all regions. This thesis explores the viability of using portfolios of wind, solar photovoltaic (PV), and lithium-ion battery energy storage systems (BESS) to provide competitively priced 24x7 load-matched power in Texas, where these technologies comprise 95% of the power plant queue seeking to interconnect to the Electric Reliability Council of Texas (ERCOT) grid. The first stage of analysis develops a linear program that identifies capital-cost- minimized portfolios of wind, PV, and four-hour Li-ion BESS capacity capable of servicing a data center’s load every hour in the year. In a second stage of analysis, a tax-neutral financial model compares the unsubsidized economics of use cases for an optimized portfolio, including selling power production on a merchant basis, selling ancillary services using the BESS, and selling a long-term 24x7 renewable energy service. The linear program finds that least-cost 24x7 portfolios capable of servicing a steady 50 MW load include on average 77 MW solar PV, 78 MW coastal wind, 74 MW north Texas wind, and 165 MW / 660 MWh BESS. At a BESS capital cost of $300 per kWh, a 24x7-capable renewable energy portfolio reaches economic parity with a fully merchant PV + wind use case when the load-matching service is priced at the long-term average wholesale energy price. While further study is necessary to assess risk management costs and strategies, this analysis provides initial indication that a 24x7 load-matching service may be an economically viable long-term contracting pathway in regions with diversified intermittent resources and wholesale markets for BESS services.Item A cash flow model of carbon capture retrofit investment in Texas power generation using Monte Carlo simulation(2021-04-28) Murosko, Andrew Makary; Dyer, James S.The retrofitting of carbon capture systems to fossil-based powerplants is increasingly critical to decarbonization efforts within the power sector. However, private retrofit investment remains limited due to substantial project costs and risks without adequate incentives. Ambiguity in climate policy design, feasibility, and influence adds to the preexisting commercial and technical risks of retrofitting. Consequently, power producers must make retrofit decisions under considerable uncertainty. This research seeks to construct a flexible discounted cash flow (DCF) model to represent plant-level retrofit decision-making within the ERCOT power system of Texas. Through Monte Carlo simulation techniques, the model incorporates both user-determined and stochastic parameters representative of the technical, financial, and policy uncertainties associated with retrofitting coal and natural gas powerplants. The model separately evaluates both the net present value (NPV) of a hypothetical standalone retrofit project and the incremental NPV comparison to the existing, non-retrofitted status quo. Model results indicate minimal commerciality for CCS retrofitting within the Texas and ERCOT markets. Disparities in parameter sensitivity by plant fuel type, driven by differences in retrofit costs and CO₂ intensities, suggest that plant type partially dictates the efficacy of decarbonization policy proposals, including a carbon tax. Sensitivity results show that existing CCS incentives and policy designs overcompensate inefficient coal plants in maximizing electricity generation for the sake of subsequent capture of the CO₂ byproduct. Future policies will likely need to both reduce the upfront cost and offset post-retrofit additional operational and fuel costs to incentivize retrofitting. Overall, the model design establishes a simple, yet flexible, tool to improve the consensus on carbon capture retrofit sensitivities, policy design, and decision-making considerationsItem A comparative analysis of conventional internal combustion vehicle and electric buses in Austin, Texas(2022-05-19) Fuentes-Afflick, Tomás; Webber, Michael E., 1971-; Lewis, Michael; Tuttle, DavidThis thesis project examines the life cycle and environmental impact of carbon dioxide (CO₂) and greenhouse gas emissions related to the city of Austin, Texas’ transition from conventional diesel buses to electric vehicle buses. I utilized a life cycle assessment model derived from two data sources. I conducted a comprehensive literature review to analyze the energy intensity and greenhouse gas emissions of electric buses and used this information to estimate the effects and externalities of a municipal program that incentivizes individuals to change their form of transportation from private vehicles to public buses. Second, I obtained data from the City of Austin and Austin Capital Metro and analyzed ridership and vehicles miles traveled (VMT) to estimate energy intensity, emissions per passenger mile traveled (PMT), and emissions per vehicle mile traveled. Because electric energy is derived from multiple sources, I considered various electricity production scenarios, including the Austin Energy mix, Electric Reliability Council of Texas’s (ERCOT) electricity production makeup, and scenarios using combinations of renewables, fossil fuels and nuclear energy. The goal was to utilize Austin as an example for other American cities that are considering a transition from diesel buses to electric buses. The analysis showed that electric buses significantly outperformed their diesel counterparts, on a CO2-equivalent basis, using every electricity mix that was evaluated, for the empty-load, half-load and full-load scenarios. For the electric buses, electricity mixes that used more renewable energy sources (i.e. wind, solar and hydropower) had lower emissions than other options, such as nuclear, coal and natural gas. The results of this thesis project will be available to policymakers and other stakeholders who are engaged in decisions about enhancing the environmental sustainability of Austin’s transit system. I hope that decision-makers within Austin Energy’s and ERCOT’s leadership will find this report valuable. I would like to share the results with other cities, in the hopes of encouraging transportation systems throughout the country to consider large-scale change to advance sustainability and mitigate the transportation-related aspects of climate change.Item A decision analysis for valuation of natural gas resources with high CO₂ in East Natuna Basin, Indonesia(2023-04-26) Mirsha, Addian; Bickel, J. Eric; Chuchla, Richard; Hovorka, SusanThe natural gas industry is experiencing greenhouse gas emissions-related challenges. The naturally occurring CO₂ in natural gas reservoirs is one of the major anthropogenic sources of atmospheric CO₂ when it is produced. Unfortunately, a significant portion of the world's natural gas resources are contaminated with CO₂, at varying concentrations. Decarbonization targets of oil and gas companies increase the difficulty in developing these challenging resources. The conventional practice of releasing the separated CO₂ gas into the atmosphere is unlikely to be favorable to the recent oil and gas companies’ (OGCs) attitude towards decarbonization. A synergy between natural gas resources with high CO₂ concentrations and oil fields with CO₂-EOR applications can effectively address the two most important issues: the environment and the economy. However, economic issues arise when opportunities for the utilization of CO₂ produced are unavailable, making saline aquifer the only realistic storage option for developing these resources in an environmentally responsible manner with carbon capture and storage (CCS) deployment. This obviously will increase resource development costs without increasing expected revenue, and lessen their financial viability. A valuation model based on decision analysis was built to assess the impact of additional costs from CCS deployment. The model focuses on the valuation of a natural gas exploration venture opportunity that potentially contains high CO₂ concentrations. The case of the Paus Prospect in East Natuna Basin, Indonesia, was selected for implementing the model due to basinal and local indications that its target reservoirs have significant CO₂ concentrations. An Indonesian PSC cashflow model was used to estimate the potential outcomes of developing this prospect. The results indicate negative expected monetary values (EMVs) for this investment opportunity by considering that aside from its incremental cost, the CCS deployment would cause a delay in development schedule. The fiscal terms improvement of the PSC and the adaptation of a tax credit for CCS were evaluated to provide recommendations for attracting investment to develop this challenging natural gas resources.Item A facies-scale chemo-lithostratigraphic composite profile of Del Rio claystone through Austin Chalk deposition, late Cretaceous, central Texas, USA(2016-05) Gabb, Kyle Christopher; Fisher, W. L. (William Lawrence), 1932-; Rowe, Harry; Hentz, Tucker FLate Cretaceous deposition (Comanche/Gulfian Series) across the San Marcos Arch of central Texas is characterized by both aluminosilicate- and carbonate-dominated mudrock successions. Twelve drill cores were recovered from the 2-acre construction site of the AT&T Executive Education and Conference Center on The University of Texas at Austin main campus. Thirteen detailed chemo-lithofacies were defined through a combination of visual description and elemental analysis utilizing energy-dispersive X-ray fluorescence (ED-XRF). Elemental analysis was undertaken at a 0.25-ft sampling interval to provide a record of facies-scale variability. A composite profile from two cores was created by identifying the boundary between the top of the Buda Limestone and bottom of the Eagle Ford Group and then splicing the records together, thus maximizing the length of the composite core to 174 ft and incorporating the Del Rio Claystone, Buda Limestone, Eagle Ford Group, and Austin Chalk formations. Lithofacies within the four formations were defined based on Dunham’s (1962) carbonate and Potter’s (1980) shale classifications. Important sedimentary structures and mineralogical compositions were identified and added as modifiers to the facies description. The shifts between the carbonate formations and the clay-rich formations are caused by changes in sea level, productivity, anoxia, and reworking by bottom currents. The Buda Limestone and Austin Chalk are identified to range in composition from limestone to marl, as the matrixes of the formations are composed of alumo-siliceous mud. Covariance of silicon with aluminum and titanium (proxies for detrital inputs) suggests that the silica is dominantly of terrigenous origin, rather than of biogenic origin. The enrichment of redox elements (molybdenum and vanadium) indicates the occurrence of anoxia during deposition of the Eagle Ford Group. The increased presence of volcanic ash beds within fossil-rich section of the Eagle Ford Group indicates that nutrients supplied by volcanism led to increased primary productivity, triggering depleted oxygen levels and anoxic bottom waters. Whereas sea level was likely the driving force that caused changes within the Del Rio Claystone, Buda Limestone, and Austin Chalk, productivity and anoxia are the drivers of transitions within the Eagle Ford Group.Item A regression analysis of the prices of ancillary services operating reserves in the Texas market(2018-05) Meng, Jingwei; Baldick, Ross; Zarnikau, Jay William, 1959-; Hersh, MattAncillary services are an important part of the electricity market to keep the system in balance. This work studies ancillary services in the ERCOT electricity market. Having a better understanding of the relationship of ancillary services to other elements including the generation levels of the various resources, the Day-Ahead Market Price, quantities of ancillary services, and changes in market rules as specified in Nodal Protocol Revision Requests (NPRRs) is meaningful to the market. This paper uses a general linear regression model, a Panel Data Model and Seemingly Unrelated Repressors and finds that Regulation Down is different from other three ancillary services in general. The results shows that coal's generation levels and NPRR352 have a significant negative influence. The Day Ahead Market Price has a significant positive influence on all the ancillary services. Effects of other elements are different.Item A study on the interdependency of hydroponic wastewater quality and the energy and costs for onsite treatment(2020-08-18) Rose, Heather; Faust, Kasey M.; Webber, Michael E., 1971-Hydroponic growing methods have the potential to use less water while producing higher yields when compared to traditional soil-based agriculture. However, hydroponic wastewater is a nutrient dense effluent that can be harmful to the environment if not managed properly. Onsite treatment and reuse of hydroponic wastewater would avoid thousands of gallons a month of freshwater use while preventing this effluent from harming receiving streams. The efficacy, energy requirements and costs of some treatment methods are not well known. To assess the efficacy of select treatment methods, the contaminants in hydroponic wastewater were measured using samples of hydroponic wastewater collected from a greenhouse test facility and analyzed by an environmental laboratory. Contaminants evaluated were Total Dissolved Solids (TDS), calcium, potassium, magnesium, total phosphorus, nitrogen, and Total Organic Carbon (TOC). Wastewater samples were also treated onsite using a sand filter, a granular activated carbon (GAC) filter, and reverse osmosis (RO). Samples of wastewater treated by these methods were then re-analyzed by the environmental laboratory and post-treatment concentrations of the studied contaminants were recorded. Sand and GAC filtration were shown to be essentially ineffective for contaminant removal due to the high concentrations of metals in the hydroponic wastewater. Reverse osmosis was the most effective treatment method, removing an average of 85% TDS concentration in wastewater samples. The results from the water quality analysis showed that Reverse Osmosis was the only treatment method that effectively removed the large concentration of metal contaminants in the wastewater. For this reason, only reverse osmosis was analyzed for energy and cost requirements for onsite treatment of hydroponic wastewater. The energy requirements to treat hydroponic wastewater onsite by reverse osmosis ranged from 3 to 43 kWh per day, depending on the facility size and percent of water treated. The annualized cost of treatment ranged from $0.63 to $2.83 per thousand gallons of water treated. Finally, a cost savings from reduced water bills analysis was also performed using local water utility prices in Austin TX. Based on the assumptions made for water meter size and monthly water use, it was found that financial savings could be achieved in all facility sizes with a payback period of 7 to 24 months if facilities utilized municipal water as their water source. These results can help to determine whether recycling hydroponic wastewater is feasible within financial and energy constraints as a way to avoid discharging harmful effluent and using thousands of gallons of source water each month.Item A techno-economic study of a CO₂-plume geothermal system in mature gas reservoirs of the Brazos Area protraction, Gulf of Mexico(2023-04-20) Klarin, Samuel Jacob; Livescu, Silviu; Chuchla, Richard J. (Richard Julian); Wisian, Kenneth; Webber, MichaelThe Brazos Area protraction of the Gulf of Mexico was the focus of exploration and development of Middle Miocene aged natural gas reservoirs along the Corsair fault trend for many decades of the late 20th century. With this development came the installation of supporting infrastructure. This included fixed offshore platforms and pipelines to bring the produced natural gas back to shore, roughly 65 kilometers in waters between 40 to 60 meters deep. As operations have shifted to deeper waters with larger reservoirs, much of this infrastructure has been left abandoned with removals being delayed due to the high decommissioning costs. Carbon capture and sequestration (CCS) and geothermal energy are two such technologies that received increased attention in the Gulf Coast region as efforts to reduce atmospheric CO₂ concentrations accelerate. Specifically, CO₂-plume geothermal (CPG) systems inject supercritical CO₂ (sCO₂) into a sandstone reservoir where the heat is extracted from the surrounding rock as the fluid migrates, then the fluid is produced into a direct-sCO₂ turbine power plant. Upon exiting the power cycle, the sCO₂ is then reinjected into the reservoir to start the sequence again. This study uses open-source well data from the National Geothermal Data System (NGDS), reservoir and infrastructure data from the Bureau of Ocean Energy Management (BOEM), and the Sequestration of CO₂ Tool (SCO₂T [superscript PRO]) software to conduct a resource assessment in terms of geothermal energy and CO₂-capacity of the gas reservoirs in the Brazos Area protraction and the potential power output and specific capital costs of greenfield and brownfield CPG systems. These characteristics are then used to adapt the CPG system to an offshore application exploiting the mature/depleted reservoir with the most potential, the BA133A_CM7D sand. This application is modeled by creating a workflow to conduct a techno-economic analysis involving three main schemes and the implications of current policy incentives under the Inflation Reduction Act of 2022, namely the 45Q carbon tax credit and the investment tax credit. The schemes analyzed are a Post-CCS CPG-only application (PCC), a combined CCS and CPG operation with newly built infrastructure (CCNB), and a combined CCS and CPG operation utilizing repurposed infrastructure (CCRI). The economic analysis yields a levelized cost of electricity (LCOE) range for the PCC scheme of 72-332 $/MWh. The reduction potential (25-78%) is driven by the amount of infrastructure reuse and ITC incentive at a 20 $/tCO₂ storage cost and 35 $/tCO₂ purchase price. The LCOE range under the CCNB and CCRI schemes are about 84-573 $/MWh (52-85% reduction potential) and 5-464 $/MWh (58-99% reduction potential), respectively. A sensitivity analysis was performed for 35, 60, and 85 $/tCO₂ purchase price and number of sCO₂ power plants (1-10) that can be installed on the platform. LCOE ranges for either CCNB or CCRI scenarios are shown to decrease from roughly 1,385 $/MWh to 441 $/MWh.Item A value of information analysis of fracture prediction methods(2017-08) Almansour, Abdulaziz Saad; Laubach, Stephen EThis thesis applies a multidisciplinary approach to evaluate the technical effectiveness and economic value of a fracture characterization method that uses limited core information (including sidewall cores) to diagnose the presence or absence of open fractures. The potential value of the technique lies primarily in completion decision making. The characterization method known as the degradation (Dg) index (Laubach, 2003) uses petrographic observations of the unfractured rock (i.e., a fracture surrogate) to overcome the inherently incomplete sampling that limits analysis of large fractures. Relying on recent insights into how progressive diagenesis and fracture growth interact, degradation index predicts whether large fractures (aperture > 0.1 mm) are sealed or open by measuring the abundance of rock-mass cement that precipitated after fractures ceased opening. I conducted an accuracy assessment of the predictions using degradation index profiles for wells from the Upper Cretaceous Mesaverde Group Sandstones, Piceance Basin in Colorado; Lower Cretaceous Frontier Formation, Green River Basin, Wyoming; Permian Wolfcamp sandstone, West Texas; and Permian Weber sandstone, Rangely Field, Colorado. Results indicate that the accuracy of the degradation index technique is around 82%. To determine the economic value of insights provided by the technique, we used decision analysis and Bayes’ theorem to perform a Value of Information (VOI) analysis. Since the parameters that go into calculating the VOI are mostly unique to specific locations and depend on the exact design of the well, I built a user-friendly spreadsheet model to calculate VOI using play-specific geologic and cost parameters. Using a range of typical costs for a vertical well drilled into a tight sandstone formation having multiple completion targets, I calculated the VOI at US$ 151,750. In the base case scenario, the VOI of the degradation index is most sensitive to completion costs, accuracy of the degradation index, expected revenue from a successful well, and probabilities we assign to the state and presence of fractures in this order.Item Aggregating pore space ownership for geologic sequestration of CO2(2011-05) Rozsypal, Audrey Marie; Groat, Charles G.; Dzienkowski, John; Duncan, IanThe injection operator for a carbon dioxide sequestration project must control the reservoir and associated pore space within the project boundaries to allow for orderly development of the storage facility. A large number of interest owners within a project area is likely to make reaching unanimous agreement among all owners of pore space unlikely, and thus control of the reservoir difficult. In order to facilitate geologic sequestration of carbon dioxide on privately owned land in the United States, or on land for which the minerals or pore space are privately owned, a scheme for aggregating the ownership of pore space is needed. To allow geologic sequestration projects to move forward with less than unanimous consent of interest owners, states can employ various methods of aggregating pore space ownership. This paper examines oil and gas unitization statues and statutes creating groundwater districts to find legislative regimes useful for achieving pore space ownership aggregation. Among the approaches discussed, aggregation of pore space ownership through a unitization model is the most likely choice. Taking that one step further and setting up new unit operating agreements for enhanced oil recovery to serve as a repository for incremental geologic sequestration, and eventual full sequestration activities, provides a firm path toward reducing carbon dioxide emissions while respecting property rights. This paper also compares the few existing pore space aggregation statutes in the United States, which achieve aggregation of pore space ownership through either unitization or eminent domain. The state that appears to be the best equipped to deal with aggregation of pore space ownership is Wyoming. Wyoming has been a leader in developing legislation to deal with pore space ownership before other states. North Dakota and Utah are also very well situated to move forward with carbon sequestration activities.Item An analysis of geothermal viability in Pecos County, Permian Basin, West Texas(2022-05-06) Pastorek, Nathan; Young, Michael H.; Wisian, Kenneth W.Pecos County, located in the Permian Basin of west Texas, is a deep sedimentary basin within which the Delaware Basin and Central Basin Platform are located. Significant oil and gas activity has occurred here over nearly 100 years. This activity has yielded substantial available well data for temperature and heat flow analyses. While several national-scale heat flow and temperature-at-depth data sets exist, very few county-level studies within Texas are available. Well data from the National Geothermal Data System (NGDS) are used to construct a Pecos County heat flow model and four temperature-at-depth models (3.5, 5.0, 6.5, and 10.0 km depths), using 947 data points available in Pecos County. Wells are distributed throughout the county, with higher well densities occurring in the north, northeast, and south-central portions. A radiogenic heat production model was incorporated to account for radioactive decay within the basement and sedimentary sections. Results show below-average heat flow (< 65 mW/m²) across the Central Basin Platform and average to above-average heat flow in the Delaware Basin in comparison to previous national heat flow models. High heat flows (>90 mW/m²) were calculated in portions of south and south-central Pecos County. Temperature-at-depth models indicate the lowest temperatures occurring across the Central Basin Platform and eastern Delaware Basin. Temperatures are elevated near the center of the county, with the highest temperatures located in south and south-central Pecos County. Temperature-at-depth model values are comparable with recorded well datapoints around the depth intervals of interest. Maximum temperatures for developed models at 3.5, 5.0, 6.5, and 10.0 km depths are 195°C, 213°C, 232°C, and 273°C, respectively. Findings show that calculated heat flow and temperature-at-depth in southern Pecos County is higher than those calculated for the region in existing national-scale models. Higher than average heat flow and temperature-at-depth anomalies can be attributed in part to higher radiogenic heat production (15.26 mW/m²) than previously estimated and increased model resolution compared to earlier national-scale heat flow and temperature models. Other possible explanations include shallow plutonic complexes, advective groundwater flow, and the Sierra Madera impact and crater. Pecos County has suitable temperatures for geothermal electricity production (> 150°C) at as shallow as 3.5 km depth, and most of the county reaches this temperature by 6.5 km depth. Opportunity exists for co-production of oil and gas and geothermal energy from existing wells at depths where this temperature is met or exceededItem An analysis of regional drought management plans in Texas(2018-11-21) Collado, Elbin Antonio; Kreitler, Charles W.; Eaton, David J.Water scarcity can be defined as a lack of enough water, or not having access to safe water supplies (Liu, Gosling and Yang). Due to population growth and shifts in rainfall over the coming decades, management of water resources may need to change. This thesis reports on how Texas deals with its current water scarcity to understand future options. While droughts cannot be prevented, the recent statewide Texas droughts in 2011 underscored the need for better preparation for responding to the impacts of drought. Having effective preparedness plans and an adequate supply is particularly critical to the proper management of water resources. (Division, 2005) This thesis describes how regions within Texas address issues such as droughts, climate change, population growth, and how Texas’s 16 Water Planning Regions respond to water shortage. Sections of the thesis examine drought preparedness strategies founding the 16 Regional Water Plans (2016). A Drought Contingency Plan (DCP) is a set of conservation measures that increase during different stages of drought. The Texas Water Development Board (TWDB) requires a DCP for any water entities that serves 3,000 connections or more. Emergency Drought Responses (EDR) are potential ways of increasing water supply during water scarcity conditions. The TWDB requires an EDR for any entities that serve fewer than 3,000 people or only have a single source of water supply. This report also includes data for water use in each Water Planning Region, to compare how much water the people in each region currently consume. After compiling information on DCPs, EDRs, and water use, the 16 Water Planning Regions were compared, and the results presented graphically. Regardless of the climate or the available water resources, Texas drought contingency strategies are similar and follow a trend to further improve conservation methods across regions. Most entities report that demand, not supply, is the biggest threat to water availability. Most plans address conditions of severe drought, but do not plan for more than the previous worst-case scenario. This thesis concludes that Texas may not be able to continue to provide water to all its consumers during the next major drought. It remains an open question whether Texas can increase supply from drought-proof sources, such as use of brackish groundwater. Drought Contingency Plans (DCP) rely mostly on consumer conservation efforts. Emergency Drought Responses (EDR) emphasize increasing water supply. My original hypothesis was that drier areas of Texas would have differing strategies than regions with ample annual rainfall. However, this research has indicated that this is not the case: DCPs and EDRs are comparable across Texas. Small communities across Texas conserve water with the limited resources they have. Large cities are improving water conservation strategies; with population growth, their conservation measures may not be enough because there is a limit to how much can be conserved.Item An analysis of renewable tax incentives and electricity pricing in Texas(2023-04-21) Rudolph, Mary (Mary Allison); Damien, Paul, 1960-; Olmstead, Sheila M.Texas has abundant natural resources, making it a good place for renewable energy facilities to build. Unfortunately, property taxes are the highest tax an incoming renewable energy facility have in the state (Texas Taxpayers and Research Association, 2021). To increase renewable energy in the state, Texas tax code Chapter 313 was introduced. Chapter 313 allows school districts the opportunity to offer a 10-year limit, ranging from 10 million dollars to 100 million dollars, on the taxable value of a new, green energy project (Texas Taxpayers and Research Association, 2021). With Chapter 313 ending in 2022, the question is: how tax incentives that increase the number of applications for producing renewable energy in ERCOT relates to wholesale, real-time pricing of electricity in the state? Skew-t regression models were implemented on a large dataset, focusing on the North, Houston, and West regions of the Electricity Reliability Council of Texas (ERCOT), since these regions account for 80% of the state's energy consumption. Analysis focused on the hours ending at 3am, 11am, and 4pm, due to ERCOT's time-of-day pricing. Energy demand is generally low at 3am, while it increases during the day, peaking around 4pm to 6pm. The regressions in this analysis are association models, meaning no causality is implied in any of the results. When tax incentives increase the number of active wind and solar facilities there is a reduction in wholesale electricity price ($/MWh), ranging between 2.31% and 6.6% across ERCOT during different hours of the day, this is statistically significant (p<0.0001). And electricity price reductions from solar are much lower than those from wind generation.Item An “inescapable obligation” : the treatment of well decommissioning liability in recent oil and gas bankruptcies(2019-12-04) Cook, Kristin Alexandra; Spence, David B.Oil prices fell by fifty percent during the latter half of 2014, tumbling from a high of $105 per barrel in June to a mere $53 per barrel by year’s end. As a result of sustained depressed commodities prices, more than 350 North American oil and gas operators and service companies filed for bankruptcy between January 2015 and September 2019, representing more than $162 billion of debt. Despite the existence of federal and state statutes ensuring that operators decommission wells at the end of economic life, these environmental laws frequently lose efficacy in bankruptcy proceedings. This unresolved conflict, among other contributing factors, has led to the existence of tens of thousands of “orphaned wells” in the United States. This thesis paper examines the bankruptcies of American oil and gas operators after the precipitous decline in oil prices to determine whether operators successfully discharged decommissioning liability during bankruptcy. A survey of 2015 bankruptcies shows that 33% of oil and gas operating companies abandoned properties with unmet decommissioning liability and created 285 new orphan wells in eight states. This paper also estimates the cost to plug and abandon wells orphaned from bankruptcies between 2015 and 2019 at more than $200 million. The paper concludes with a discussion of the advantages and disadvantages of several possible solutions to the orphan well problem.Item An analysis for promoting residential-scale solar photovoltaic (PV) in Bangkok, Thailand(2015-12) Chaianong, Aksornchan; King, Carey Wayne, 1974; Pharino, ChanathipSolar Photovoltaic (PV) has a significant potential for distributed energy in the urban environment of Bangkok, Thailand in order to decrease the country’s reliance on imported conventional energy and enhance the country’s energy security. This research analyzes the technical, economic and policy analysis of installing 3,000 MW (Thailand’s solar PV goal) of residential solar PV in Bangkok using System Advisor Model (SAM) and also compares each analysis to large-scale load (e.g. manufacturing). In technical analysis, the relationship of distributed solar energy and electric load from the grid is analyzed. While the residential load and peak solar irradiance are not correspondent for residential scale, generating electricity from 3,000 MW of solar PV can still decrease residential daily load consumption from the grid by 38 percent. On the other hand, the distributed of solar energy and large-scale load are well matched. As a result, the large-scale peak load can be reduced by 16.7 percent from 3,000 MW solar installation. Regarding to economic analysis, the levelized cost of energy of residential scale is higher than large scale. Without tariff, costs of solar electricity are higher than grid price. Therefore, it is necessary to introduce solar tariff to encourage people to install solar PV. Throughout solar project’s lifetime, with current Thailand’s solar incentives (Feed-in Tariff; FIT), solar project investments of both scales seem feasible from financial perspectives under Thai’s government cost assumptions. In addition, due to the increasing urbanization rate and typical land use of Bangkok, residential solar PV seems to be the better candidate. However, some technical and policy barriers remain, such as the lacks of skilled manpower, policy mix, and financing options as well as the inconsistence of governmental support. It is essential for Thai government to overcome these barriers in order to create sustainable growth of solar PV in the country.Item Analysis of hydrocarbon under-filled Miocene deep-water reservoirs, eastern Mexico offshore(2019-09-17) Apango Perez, Fernando Agustin; Snedden, John W. (John William); Chuchla, Richard J. (Richard Julian)Hydrocarbon exploration in the deep-water portion of the southwestern Gulf of Mexico commenced a decade ago, but discoveries have not been able to meet the optimistic expectations based on historical success in the northern Gulf of Mexico. Based on the existence of organic-rich source rocks and high-quality Miocene reservoir rocks, this research initially hypothesized that the lack of significant hydrocarbon accumulations in some prominent traps in the northern Catemaco fold belt (Veracruz Trough) is the result of an ineffective sealing and/or trapping mechanism. By integrating well core, 3D seismic, and other well data provided by the Mexican National Hydrocarbon Commission, this thesis attempts to determine the cause of hydrocarbon under-filled or dry Miocene traps within the Veracruz Trough using the structures drilled by Pemex-operated Kunah-1 and Yoka-1 wells as case studies. Three hypotheses are considered and analyzed: top seal leakage, the existence of unmapped shallow spill points, and late trap formation relative to the timing of hydrocarbon charge. Seal bed leakage analyses, which involved pressure data analysis and MICP laboratory measurements on cuttings, suggest that the evaluated intra reservoir and top seal rocks are at least moderately effective. In addition, 3D seismic structural interpretation around the Yoka-1 trap strongly suggests that the spill points are much deeper than fluid contacts. However, the trap formation assessment showed that by the time the traps began to develop, the oil generation phase was exhausted and gas generation was at a very late stage for the most prominent source rocks. Consequently, a more robust explanation for the Kunah-1 and Yoka-1 under-filled structures is poor timing between the generation and migration of hydrocarbons and trap volume evolution. A high-level economic assessment was made to determine if it would be commercially viable to produce some of the natural gas reserves that have already been found in the Catemaco fold belt. A notional gas development that would tie in production from the Kunah, Lakach, and Piklis fields into an onshore gas processing plant, was proposed and analyzed. The net present value calculated for this project suggests that the high costs of building the required infrastructure and the relatively low forecasted future prices of natural gas, make the profitability of a deep-water gas development project around the study area unlikely at the present timeItem An analysis of Latin America’s electricity market restructuring efforts : the role of energy regulators, performance, and competition(2009-12) Baca Bañuelos, Miguel Alejandro; Spence, David B.; Foss, MichelleThis thesis reviews restructuring efforts of the electricity market in Latin America. The work first examines the drivers that have encouraged Latin American countries to restructure their power markets, going from government-held monopolies to fully privatized systems. Then a general conceptual theory is presented to describe the main differences between restructuring and privatization, and antitrust theory. Next, five countries are selected due to their leadership role in electric reforms in the region as well as their economic weight. Then a complete description of their power generation and electricity consumption is described as well as their experiences undergone before and after electricity restructuring. A summary section is presented by benchmarking the five countries and identifying the common issues faced that will help others plan better electric systems. Then, an analysis of their internal market competition is presented, analyzing the impact of electricity costs and rates. Finally, the last portion of this thesis concludes by exploring future trends in market integration programs as well as the challenges for sustainable economic growth, environmental impacts, and cooperation.Item Analysis of oil spill strategies in the Canadian Beaufort Sea(2016-05) Lee, Beomrak; Fisher, W. L. (William Lawrence), 1932-; Malik, Krishan A.; Dunton, Kenneth H.The objective of this study is to apply historical data on ice concentration, temperature, sea level, salinity and wind speed to an evaluation of the effectiveness of oil spill responses in various seasons and regions. Keeping operations safe on ice is critical to Arctic exploration and production. Specialized construction techniques and engineering designs are required for the harsh environment in the Arctic. Factors that trigger marine oil spills include accidents involving oil transportation vessels carrying large quantities of fuel oil, releases from on-land storage tanks or pipelines that travel to water, acute or slow releases from subsea pipelines and hydrocarbon well blowouts during subsea exploration or production. In addition, dynamic ice cover, low temperatures, reduced visibility or darkness, high winds and extreme storms increase the probability of a marine oil spill. The Arctic remains among the harshest, coldest and most remote places elevating both the risk of spills and their potential impact. In order to identify effective oil spill strategies, a careful assessment of the benefits, limitations and tradeoffs related to available response techniques must be made. The findings presented here will help stakeholders select appropriate response strategies in the Arctic.Item An analysis of the city of Austin pipe networks using network and information theory metrics(2016-05) Haegele, Tess Marian; King, Carey Wayne, 1974; Huber, Karen; Faust, KaseyAustin’s rapid population growth over the past few decades has given rise to the need for additional water infrastructure and supply. There are limited funds for investment in water infrastructure so it should be spent with the goal of optimizing system robustness. A robust system comes from a balance of efficiency and redundancy. There are two methods used in this analysis to establish baseline metrics. Information Theory and Network Theory are based on the connectivity of the system looking at efficiency and redundancy. These theories are used by first converting the water pipe networks into a graph of nodes and links, extracting a connectivity matrix, and converting the data to “igraph” format in the statistical computing software R for analysis. The Network Theory calculations are built in to the “igraph” package in R and the Information Theory calculations are based on the equations developed by Robert Ulanowicz. The starting point metrics of this study can be replicated for the main and wastewater systems and built upon considering operational and hydraulic characteristics unique to the system in future work, and eventually inform utility decisions.Item Analysis of the evolving relationship between NOCs and IOCs : the Venezuelan case(2005-12) Briceno, Romulo P.; Van Rensburg, W. C. J.Close to ninety percent of the world's oil reserves are owned by governments and partially privatized National Oil Companies (NOCs), and any investment by the International Oil Companies (IOCs) is bound to involve a close interaction between them. Nowadays, with higher demand for oil, particularly in the United States and China, international oil investment has grown progressively because of the need to balance supply and demand. Therefore, it appears reasonable to expect more balanced agreements in which the contractual conditions are fair to all sides, allowing an increase in petroleum exploration activity. The objective of this thesis is to understand and analyze the evolving relationships between the International Oil Companies and the National Oil companies with a special focus on The Bolivarian Republic of Venezuela and its National Oil Company, Petróleos de Venezuela, S.A. (PDVSA).