The combustion of fossil fuels results in the release of carbon dioxide to the atmosphere, a known greenhouse gas. Evidence suggests that “most of the observed increase in global average temperatures…is very likely due to the observed increase in anthropogenic greenhouse gas concentrations” (IPCC, 2007). One solution currently being examined is carbon capture and storage (CCS). The advantage of CCS is that it does not require an actual reduction in the amount of carbon dioxide emissions created, but reduces emissions to the atmosphere by storing the greenhouse gases in the subsurface. Fundamentally, CCS works in the reverse of oil and gas production. Instead of extracting fluids from the subsurface, CCS injects carbon dioxide (CO2) into the pore spaces of developed oil and gas reservoirs, saline aquifers, or coal bed seams (Bachu, 2007), where it exists in a dense but low-viscosity phase (Supercritical state). The Gulf Coast Carbon Center, based at the University of Texas at Austin’s Bureau of Economic Geology, is currently evaluating the State of Texas Offshore Lands (STOL) in the Gulf of Mexico (GOM) in order to evaluate the carbon-storage capacity in the state owned lands. “Capacity is defined as the volume fraction of the subsurface within a stratigraphic interval available for [CO2] sequestration” (Hovorka, 2004). There are a variety of methods currently used to calculate capacity. With so many options, how does a project decide which method to employ in determining capacity? This paper discusses the methods, presents an analysis of the benefits and drawbacks of the various methods, and develops a process for future projects to utilize in determining which methodology to employ. Additionally, storage capacity is calculated using the various methods presented, in order to compare the methods and understand their various advantages and drawbacks. Reservoir specific simulations are expected to predict smaller capacities in comparison to more broad static methods. This will provide end member predictions of capacity, shedding light on what can be expected in best case and worst case scenarios. The lessons learned from this study can be applied to future endeavors and formations all over the world. / text

The research presented in this thesis examines the use of electric vehicles and renewable energy to reduce emissions of CO₂, SO₂ and NO[subscript x], and within the state of Texas. The analysis examines the impact of increased renewable energy output and electric vehicle charging on the emissions of fossil fuel electric generators used to serve the bulk power system within Texas. The analysis then compares those impacts to alternative scenarios in which fossil fuel generation replaces some renewable energy generation, and Internal Combustion Engine (ICE) vehicles of varying efficiency are used instead of electric vehicles. This research uses temporally-resolved regression analysis combined with a unit commitment and dispatch model that incorporates several different scenarios for EV charging and fuel mixes to evaluate emissions outcomes based on a variety of conditions. Hourly historical generation and emission data for each fossil fuel generator, combined with hourly output data for non-fossil fuel units aggregated by fuel type (i.e. nuclear, wind, hydro-electric) within the Electric Reliability Council of Texas (ERCOT) footprint is regressed to assess the impact of wind generation output on fossil-fuel generation emissions. The regression analysis is used to assess potential increases in emissions resulting from the ramping of fossil-fuel Electric Generation Units (EGUs) to compensate for variability in wind generation output due to changing weather conditions. The unit commitment dispatch model is used to evaluate the impact of changes in customer demand due to increased usage and charging of electric vehicles on the ERCOT system and any resulting increase in emissions from generation used to meet this new demand. The model uses detailed cost, performance and emissions data for EGUs in the ERCOT footprint to simulate the impact of a variety of charging scenarios and fuel mixes on EGU dispatch patterns and any resulting change in system-wide emissions. The results of this model are combined with the results of the regression analysis to present a more complete analysis of the combined impacts of increase EV and renewable energy usage on the emissions of CO₂, SO₂ and NO[subscript x] within the ERCOT footprint. Based on these analyses the increases in renewable energy generation demonstrate clear benefits in terms of emission reductions when the impacts of increased emissions due to more frequent ramping of fossil-fuel units are taken into account. This analysis also finds that EV charging generally has emissions benefits across a range of charging patterns and bulk power system fuel mixes, although in certain circumstances EV charging might result in higher emissions than the use of ICE vehicles. This research finds when future ICE vehicles with reduced emissions are taken into account, approximately half of the modeled scenarios show net emissions benefits from EV charging, while half show net emissions costs when emissions impacts across pollutants are taken into account. / text

The broad objective of this thesis involves investigation of the role agriculture might play in a society wide greenhouse gas emissions reduction effort. Specifically, the breakeven price for carbon emission offsets is calculated for agriculturally based emission reducing practices. The practices investigated in the Texas High Plains involve reduced tillage use, reduced fallow use, reduced crop fertilization, cropland conversion to grassland, feedlot enteric fermentation management and digester based dairy manure handling. Costs of emission reductions were calculated at the producer level. The calculated offset prices are classified into four cost categories. They are: negative cost, low cost (less than $20 per ton of carbon saved), moderate cost ($20 through $100 per ton of carbon saved), and high cost (over $100 for tons of carbon saved). Negative cost implies that farmers could make money and reduce emissions by moving to alternative practices even without any carbon payments. Alternatives in the positive cost categories need compensation to induce farmers to switch to practices that sequester more carbon. All fallow dryland crop practices, dryland and irrigated cotton zero tillage, dryland and irrigated wheat zero tillage, irrigated corn zero tillage, cotton irrigated nitrogen use reduction under minimum tillage and dryland pasture for all systems, and anaerobic lagoon complete mix and plug flow systems fall in the negative cost category. Dryland and irrigated wheat under minimum tillage are found to be in the low cost category. Cotton dryland under minimum tillage and cotton irrigated with nitrogen use reduction under zero tillage fell into the moderate cost class. Both corn and cotton irrigated minimum tillage are found to be in the high cost category. This study only considers the producer foregone net income less fixed costs as the only cost incurred in switching to an alternative sequestering practice. More costs such as learning and risk should probably be included. This limitation along with other constraints such as use of short run budget data, lack of availability and reliability of local budgets, overlooking any market effects, and lack of treatment of costs incurred in selling carbon offsets to buyers are limitations and portend future work.

Recent scientific findings have generated considerable concern about the adverse effect of greenhouse gas (GHG) emissions on the world's climate in general and global warming in particular. In Canada and many other countries, this concern has led to the adoption of legal and political steps with the aim of curbing GHG emissions. The first part of this thesis describes the steps taken by Canada in this regard. / Such steps provide a strong incentive to Canadian power systems to incorporate reduction of GHG emissions in their planning process. Thus, in the second part of the thesis, a long-term supply mix planning model is developed. Since significant decrease in GHG emissions is unlikely to occur without removal of highly polluting power plants, this model allows for decommissioning these power plants. / Finally, the supply mix planning model is applied to evaluate the strategy of joint planning (as opposed to separate planning) of the power systems of Quebec and Ontario. Results obtained from the model leads to the conclusion that joint planning is preferable from the point of view of overall social and financial cost.

Canada’s emissions are nearly 30 per cent above its Kyoto target. Kathryn Harrison is looking to understand why some countries are leading the way and why others are falling short.

The United States and NATO Allies have a national security problem that is the product of America being the home of inexpensive and plentiful modern energy. A century of cheap and plentiful domestic supplies of oil has resulted in the architecture of civilian and military systems that are premised on the continued availability of cheap, high gradient conventional energy. As the pre-eminent military power of the last century, America ensured that access to secure “rear” areas, bases and supply lines can be relied on – at least until recently. With the increasing prevalence of asymmetric warfare conducted primarily with non-state actors and the loss of America’s monopoly on precision munitions (PGMs), or in the event of conflict with peer competitor states, security of supply lines, staging and rear areas can no longer be taken for granted. For expeditionary forces, supply of conventional liquid fuels represents a sizable amount of tonnage required to transport combat units to battle and conduct operations. Supplies are primarily conveyed by inherently vulnerable platforms like tankers and stockpiled in difficult to harden warehouses or dumps. While there is no shortage of petroleum or conventional fossil energy worldwide, the sheer volume of fuel presently needed to conduct modern expeditionary military operations itself creates vulnerabilities. The DoD and individual services have in place long-term programs to reduce the energy intensity with valuable lessons for NATO allies as most military systems and doctrine are patterned after DoD architectures. Transfer of techniques for reducing energy intensity from defense to the civilian sector has spinoff benefits overall; for example, by making operations in remote locations such as the Arctic / Antarctic more affordable and practical, and enabling a more energy / resource efficient civilian economy. Benefits from reduction of energy use include the reduction of signatures from energy use that are expensive and difficult to mask or hide, potentially reducing vulnerabilities in both the military and civilian infrastructure. Despite these benefits, legacy systems architectures in both defense and civilian limit energy efficiency gains. Technological advances of the past century have enabled many functions such as HVAC and lighting to be met with low gradient, low density and intermittent energy if systems are re-architectured. New designs, if standardized and rolled out quickly, offer the potential to benefit from making use of renewables like solar, wind, micro-hydro, or to use conventional high gradient energy more efficiently in combined cycle systems that often can be locally sourced even for remote forward operating bases. Low gradient energy systems, by their nature, present a smaller emissions signature issue. US-DoD has an opportunity to drive the development of the implementation of these high efficiency technologies and institutions and accelerate their spread to the civilian economy. This thesis presents a vision of a technically, politically, economically and logistically viable pathway to a cleaner and more sustainable alternative to current dominant energy systems architecture and provides a roadmap to implementation

Continuous culture fermentation (CCF) was used to test the hypotheses that: marine microalgae (MA) and macroalgae (seaweeds) alter rumen microbial metabolism; MA types differ in abilities to provide rumen escape n-3 polyunsaturated fatty acids (PUFA); and algae have the potential to reduce enteric methane emission. The CCF system of Teather and Sauer (1988) was modified to reduce clogging, refrigerate effluent, and allow for determination of gas production. The CCF systems were inoculated with pooled rumen fluid from 4 cows. Total mixed ration was fed at the rate of 30 g DM d-1. Temperature was maintained at 39 oC, and buffered with artificial saliva to maintain pH 6.2. Response variables were measured from effluent digesta (fatty acids, NH4+-N, digestibility), fermentor contents (CCF density, volatile fatty acids), and the gas phase (CO2, CH4). The experimental design for MA testing was a 3**3 factorial. Treatments consisted of heterotrophic and photoautotrophic MA as well as a 1:1 blend with protection levels of zero, 33 and 50 % of encapsulation (w/w), and fluid turnover rates of 5, 7.5, and 10 % h-1. The seaweed treatments consisted of a PEI shoreweed mix containing Laminaria longicruris and Fucus vesiculosus tested as a component of the mix, and Chondrus crispus and Furcellaria fastigiata tested individually. The design for seaweed testing was an unbalanced 5*5 Latin square. The heterotrophic MA destabilized the digesta mat while the autotroph improved stability. Biohydrogenation was extensive for C18 FA in the basal ration (> 90 %) and less for C22:6n3 (75 %) from the heterotroph and C20:5n3 (60 %) from the photoautotroph. The recovery of PUFA was improved by encapsulation, however PUFA in the MA were not greatly affected and digestibility was improved by turnover rate. Seaweeds had no effect on CCF stability, however they reduced CH4 production without reduction in OM digestibility. The heterotroph reduced overall fermentation resulting in diminished density and volatile fatty acids and NH4+-N concentrations. Seaweed supplementation decreased NH4+-N, CO2 and CH4 production, and increased density.

Recently, electric vehicles (EVs) have been gaining attention in passenger transportation due to their greater fuel economy and reduced greenhouse gas (GHG) emissions compared to conventional vehicles (CVs). The amount of GHG emissions reduction from EVs depends on the energy sources used to generate electricity. Wind is a clean, renewable energy source and EVs charged from wind-generated electricity do not produce any emissions. However, wind is variable in nature. This thesis examines the potential impact of EVs on reducing a jurisdiction’s vehicular GHG emissions using locally available wind-electricity. Four methods of charging EVs using wind-electricity are considered, with grid-electricity as a backup, and the overall well-to-wheels GHG emission reductions are discussed. The thesis includes a case study of Summerside. The results show that up to 68% of the EVs’ demands were met with wind-electricity, and Summerside’s vehicular GHG emissions were reduced by between 56% and 73% when compared to CVs.

Energy crops may present an opportunity to reduce Nova Scotia’s Greenhouse Gas emissions by offsetting fossil fuel use and provide economic benefits for farmers. They have also received government policy support. To investigate this opportunity, I conduct a partial social cost-benefit analysis using non-equity weighted monetary valuation of growing switchgrass on inactive and underused farmland in Nova Scotia for local residential heating. The private net benefit for farmers, processors and consumers is estimated between $24.9 million and $209.9 million. I estimate that the external net benefit to society from the potential reduction in GHG emissions (at $50/tonne CO2E) ranges from $11.3 million to $72.2 million. This must be taken with caution as the analysis does not account for the entire ecological footprint of the project. While a net benefit to society is suggested, the paper also points to a need for more research surrounding the life-cycle emissions of energy crops.

The quality of the human experience depends on a dramatic change in how we think about economics and, more specifically, about the relationship between human economic activity and the natural world. The continued pursuit of a growth agenda threatens the health and stability of global ecological systems, jeopardizes the wellbeing of many people, and undermines opportunities for future generations. In an era of sustainability challenges, we must measure the impacts of economic activity and use that information toward designing more sustainable human systems. This dissertation supports an ecological economic worldview by extending biophysical based measures to local scale applications to improve understanding of environmental impact at the urban and sub-regional scale. To account for environmental impact, I test two calculation approaches: one to estimate municipal ecological footprint values and one to measure environmental impact at a neighbourhood level. The novel calculation approaches account for environmental impact at finer scales of resolution than has traditionally been applied. I also explore drivers of environmental impact using Halifax Regional Municipality as a case study. I examine the relationship between direct GHG emissions and socio-economic and wellbeing variables using a multivariate model. Those reporting to be married, young, low income, and living in households with more people have correspondingly lower direct GHG emissions than other categories in respective groupings. Respondents with lifestyles that generate higher GHG emissions did not report to be healthier, happier or more connected to their communities, suggesting that individuals can experience similar degrees of wellbeing largely independent of their GHG emissions. I explored whether where we live influences direct GHG emissions. Findings indicate that individuals living in the suburbs generate similar GHG emissions to those living in the inner city, challenging a widely held assumption that living in the inner city is better for sustainability. These results underscore the importance of understanding the spatial distribution of GHG emissions at the sub-regional scale. The research offers new insights to measure and understand environmental impact at the local level toward supporting ecologically informed decision-making.