Browsing by Subject "coal"

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A Feasibility Study for Mapping Abandoned Coal Mining Areas in Young County, Texas
(1979) Finley, Robert J.; Hupp, William H.
A total of 276 sites of possible bituminous coal mining were located within Young County, Texas, using black-and-white aerial photography at a scale of 1:20,000. More than 80 percent of these sites are less than 10 acres in size; 14 sites are 40 acres or more in size. Lack of vegetation, disturbed land surfaces, and evidence of active erosion characterize these sites. Forty-five sites are either directly adjacent to natural streams or show distinct runoff channels entering natural streams. Historical mining records were utilized where available, but no field confirmation of sites was included as part of this feasibility study.
Backyard Politics, National Policies: Understanding the Opportunity Costs of National Fracking Bans
(2013-12-31) Spence, David B
Bringing Climate Action ‘Down Under’: The Politics of Climate Change in Australia
(2015-09-16) Webb, Romany
Can switching fuels save water? A life cycle quantification of freshwater consumption for Texas coal-and natural gas-fired electricity
(IOP Publishing, 2012-10-08) Grubert, Emily A.; Beach, Fred C.; Webber, Michael E.; Grubert, Emily A.; Beach, Fred Charles, 1959-; Webber, Michael E.
Thermal electricity generation is a major consumer of freshwater for cooling, fuel extraction and air emissions controls, but the life cycle water impacts of different fossil fuel cycles are not well understood. Much of the existing literature relies on decades-old estimates for water intensity, particularly regarding water consumed for fuel extraction. This work uses contemporary data from specific resource basins and power plants in Texas to evaluate water intensity at three major stages of coal and natural gas fuel cycles: fuel extraction, power plant cooling and power plant emissions controls. In particular, the water intensity of fuel extraction is quantified for Texas lignite, conventional natural gas and 11 unconventional natural gas basins in Texas, including major second-order impacts associated with multi-stage hydraulic fracturing. Despite the rise of this water-intensive natural gas extraction method, natural gas extraction appears to consume less freshwater than coal per unit of energy extracted in Texas because of the high water intensity of Texas lignite extraction. This work uses new resource basin and power plant level water intensity data to estimate the potential effects of coal to natural gas fuel switching in Texas’ power sector, a shift under consideration due to potential environmental benefits and very low natural gas prices. Replacing Texas’ coal-fired power plants with natural gas combined cycle plants (NGCCs) would reduce annual freshwater consumption in the state by an estimated 53 billion gallons per year, or 60% of Texas coal power’s water footprint, largely due to the higher efficiency of NGCCs.
Coal Ash Disposal Challenge (Part 1)
(The Center for Global Energy, International Arbitration, and Environmental Law, 2014-06-13) Baumstark, Kristine
Coal Ash Disposal Challenge (Part 2)
(The Center for Global Energy, International Arbitration, and Environmental Law, 2014-06-20) Baumstark, Kristine
Coal relegated to the back burner: More countries look to natural gas for electricity generation
(The Center for Global Energy, International Arbitration, and Environmental Law, 2015-02-24) Webb, Romany
Coal, lignite and asphalt rocks
(University of Texas at Austin, 1902-05) Phillips, William Battle
The Coal, Lignite and Asphalt Rocks of Texas
(University of Texas at Austin, 1904-05) Phillips, Dr. W.B.
Comparing post-combustion CO2 capture operation at retrofitted coal-fired power plants in the Texas and Great Britain electric grids
(IOP Publishing, 2011-04-07) Cohen, Stuart M.; Chalmers, Hannah L.; Webber, Michael E.; King, Carey W.; Cohen, Stuart M.; Webber, Michael E.; King, Carey W.
This work analyses the carbon dioxide (CO2) capture system operation within the Electric Reliability Council of Texas (ERCOT) and Great Britain (GB) electric grids using a previously developed first-order hourly electricity dispatch and pricing model. The grids are compared in their 2006 configuration with the addition of coal-based CO2 capture retrofits and emissions penalties from 0 to 100 US dollars per metric ton of CO2 (USD/tCO2). CO2 capture flexibility is investigated by comparing inflexible CO2 capture systems to flexible ones that can choose between full- and zero-load CO2 capture depending on which operating mode has lower costs or higher profits. Comparing these two grids is interesting because they have similar installed capacity and peak demand, and both are isolated electricity systems with competitive wholesale electricity markets. However, differences in capacity mix, demand patterns, and fuel markets produce diverging behaviours of CO2 capture at coal-fired power plants. Coal-fired facilities are primarily base load in ERCOT for a large range of CO2 prices but are comparably later in the dispatch order in GB and consequently often supply intermediate load. As a result, the ability to capture CO2 is more important for ensuring dispatch of coal-fired facilities in GB than in ERCOT when CO2 prices are high. In GB, higher overall coal prices mean that CO2 prices must be slightly higher than in ERCOT before the emissions savings of CO2 capture offset capture energy costs. However, once CO2 capture is economical, operating CO2 capture on half the coal fleet in each grid achieves greater emissions reductions in GB because the total coal-based capacity is 6 GW greater than in ERCOT. The market characteristics studied suggest greater opportunity for flexible CO2 capture to improve operating profits in ERCOT, but profit improvements can be offset by a flexibility cost penalty.
Computerized Calculation of Lignite Resources in Texas
(1983) Tewalt, Susan J.; Kaiser, W. R.
The Bureau of Economic Geology (BEG) is currently utilizing the National Coal Resources Data System (NCRDS) to estimate near-surface lignite resources in the state of Texas. Data provided to the BEG for this project primarily consist of geophysical logs from holes drilled for lignite exploration. These logs, obtained from industry sources on a proprietary basis, typically include density and resistivity traces, with occasional availability of natural gamma data. The boreholes average 150-200 ft in depth, with some reaching depths of up to 300 ft. Due to the distribution of the data, accurate correlation of individual lignite seams is challenging. Therefore, resources are calculated by summing the thicknesses of seams encountered in each borehole (total lignite). There is no standardized NCRDS method for selecting data for the calculation of total coal resources; however, the BEG has developed a method through a series of trial methods. The process begins with using PACER to search TXSTRAT for all information within a specified topographic quadrangle and a surrounding three-mile border. The additional border is included to ensure that resource calculation encompasses inferred resources from points located outside the quadrangle's latitudinal and longitudinal limits. All non-lignite (rock) lithologies in this initial file are then set to zero thickness, resulting in a file containing all data point locations with zero total thickness. Next, the initial file is searched again for lignite lithologies in the three thickness categories specified by the USGS and two additional thickness categories used in Texas (2 to 3 ft, and greater than or equal to 3 ft). Five lignite files are generated based on these thickness categories and merged one at a time with the zero-thickness file. The thicknesses are then summed in each borehole for all five files. Data locations (boreholes) without coal or with seams thinner or thicker than the searched thickness category are assigned zero total thickness. This control mechanism improves interpolation of thicknesses between points. While subsequent resource estimates may be conservative, this method prevents unrealistically large tonnages in the inferred resource category, addressing a major issue observed in earlier methods.
The Costs of Inaction: The Risks of Failing to Implement the Clean Power Plan
(2015-11-13) Webb, Romany
Delineation and Environmental Geologic Evaluation of Abandoned Coal Mines in North Central Texas
(1979) Finley, Robert J.; Caran, S. Christopher; Hupp, William H.
An environmental geologic survey of abandoned bituminous coal mines in North-Central Texas located 140 confirmed and probable mines in 12 counties. Previously, 67 mines were known, although some locations were found to be inaccurate. Present surface conditions at the mine sites have been evaluated relative to the need for possible reclamation. Based on the oldest available (and more recent) 1:20,000 to 1:40,000 scale aerial photography, low-altitude aerial observation, and ground confirmation, mining and subsequent mine abandonment have resulted in five major effects. These are: Devegetation, in part due to leachates from mine spoil. Erosion by gullying, sheetwash, and mass wasting. Increased sedimentation in tanks and streams. Ground surface subsidence. Accumulation of mine spoil, deteriorated equipment, and other refuse. The coals, mined from the 1850s to the 1940s, are in the middle and late Pennsylvanian Strawn, Canyon, and Cisco Groups. Mining was primarily underground by a modified longwall advancing method. A total of 585 acres has been affected by mining, with 142 acres in Young County (13 confirmed mines), 94 acres in Palo Pinto County (16 confirmed mines), and 45 acres in Wise County (15 confirmed mines). The greatest surface effects are evident near Thurber in Erath County and at Strawn in Palo Pinto County, where extensive spoil piles are present. Near Bridgeport in Wise County, shale in the spoil piles has been used in brick-making. Presently there is renewed interest in these bituminous coal resources, and exploration is active.
The Economic Regulation of Western Coal Transportation: An Unnecessary Conflict Between National Energy and Transportation Policies, PRP 38
(LBJ School of Public Affairs, 1980) Boske, Leigh B.
Economics, not Regulations, are Killing Coal Plants
(2018-03-13) Brooks, Steve
Energy in Texas Volume I: Electric-Power Generation, PRP 7
(LBJ School of Public Affairs, 1976) Blissett, Marlan; Haynes, Kingsley E.; Tolo, Kenneth
Energy in Texas Volume II: Policy Alternatives, PRP 7
(LBJ School of Public Affairs, 1974) Blissett, Marlan; Rohlich, Gerard A.; Johnson, Corwin W.; Callero, Monti
EPA's Clean Power Plan: Implementation Options
(The Kay Bailey Hutchison Center for Energy, Law, and Business, 2015-06-23) Webb, Romany; Taylor, Melinda
EPA’s Clean Power Plan Gives States Much Needed Flexibility in Reducing Power Sector Emissions
(The Kay Bailey Hutchison Center for Energy, Law, and Business, 2015-08-10) Webb, Romany
Estimation of Uncertainty In Coal Resources
(University of Texas at Austin. Bureau of Economic Geology, 1983) Tewalt, Susan J.; Bauer, Mary A.; Mathew, David; Roberts, M. P.; Ayers, Jr., W. B.; Barnes, J. W.; Kaiser, W. R.
Official estimates of United States coal resources published during the past 15 years vary from less than 1.5 to 3.5 trillion metric tons (1.7 to 3.9 trillion short tons). These differences imply that a high degree of uncertainty exists in resource assessment. This report identifies sources of uncertainty in coal resource estimation. Our report focuses on the comparison of variability in coal resource estimates in areas of different ancient depositional environments. The Texas Gulf Coast Basin was chosen for this study because it exhibits a full range of ancient depositional environments: (1) upper alluvial plain, (2) lower alluvial/upper delta plain, (3) delta plain, and (4) strandplain/lagoonal. Four lignite deposits, each representing one of these depositional environments, were evaluated. Important sources of uncertainty in resource estimation include variability of seam thickness, areal distribution, and the number of seams. To test the degree of uncertainty caused by variations in seam thickness, the numbers of boreholes considered in each lignite deposit are reduced and resources calculated for each reduction in data. Various techniques of resource calculation (manual, computer, and geostatistical) are used to investigate the uncertainties associated with each method. Classical statistics is the method used to determine the number of boreholes required to obtain resource estimates of individual seams within a given confidence interval under specified conditions; geostatistical methods (variograms and kriging) are used to measure variability in resource estimates. Classical statistical methods show that the minimum number of evenly distributed boreholes required to characterize resources of a lignite seam to within a precision of 20 percent is substantially less than might be expected intuitively, and depends on the coefficient of variation of seam thickness. Geostatistical methods indicate that a substantial further reduction in the minimum number of boreholes is possible when a spatial dependency structure can be established by means of a variogram. Resource figures for seams calculated by manual, computer, and geostatistical methods at various levels of data density are well within those predicted by classical statistical theory. These studies demonstrate that the maximum seam thickness variation occurs at the margins of lignite seams and that variations in thickness of individual lignite seams are not a major source of uncertainty in resource estimation, given the level of data usually available. However, determination of the areal extent and seam boundaries of coal beds is a major source of uncertainty. Data availability for regional-scale resource analysis nullifies seam-by-seam (deposit) methodologies. Our regional test area was the Wilcox Group outcrop in east-central Texas. Geostatistics did not yield a dependency structure for the entire area, therefore alternate methods were used: (1) equal weighting over the entire area: (2) equal weighting within grid cells; and (3) equal weighting within internally homogeneous blocks chosen using statistical or geologic parameters. Our methodology was successfully transferred to the Tongue River Member, Wyoming, and the Allegheny Formation, Ohio. Tonnages calculated for Wyoming and Ohio exceeded official estimates because we included deep-basin, thick continuous coals. Depositional models were used to calculate resources for the entire Gulf Coast. Calculated resources indicate the magnitude of total resources but do not quantitatively measure the associated uncertainty.