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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Greenhouse gas emission from a Prairie pothole landscape in Western Canada

Dunmola, Adedeji Samuel 10 April 2007 (has links)
Knowing the control of landscape position in greenhouse gas (GHG) emission from the Prairie pothole region is necessary to provide reliable emission estimates needed to formulate strategies for reducing emission from the region. Presented here are results of a study investigating the control of landscape position on the flux of nitrous oxide (N2O) and methane (CH4) from an agricultural soil. Field flux of N2O and CH4 and associated soil parameters from the Upper, Middle, Lower and Riparian slope positions were monitored from spring to fall of 2005, and spring of 2006, at the Manitoba Zero-Tillage Research Association (MTRZA) farm, 17.6km North of Brandon, MB. The field site consisted of a transect of 128 chambers segmented into the four landscape positions, with either all chambers or a subset of the chambers (32) sampled on select days. Spring thaw is an important period for annual inventory of N2O emission, thus, soil samples were also collected from the four slope positions in fall 2005, and treated in the laboratory to examine how antecedent moisture and landscape position affect the freeze-thaw emission of N2O from soil. Daily emissions of N2O and CH4 for 2005 were generally higher than for 2006, the former being a wetter year. There was high temporal variability in N2O and CH4 emission, with high fluxes associated with events like spring thaw and fertilizer application in the case of N2O, and rapid changes in soil moisture and temperature in the case of CH4. There was a high occurrence of hotspots for N2O emission at the Lower slope, associated with its high soil water-filled porosity (WFP) and carbon (C) availability. The Riparian zone was not a source of N2O emission, despite its soil WFP and organic C being comparable with the Lower slope. The hotspot for CH4 emission was located at the Riparian zone, associated with its high soil WFP and C availability. The Upper and Middle slope positions gave low emission or consumed CH4, associated with having low soil WFP and available C. This pattern in N2O and CH4 emission over the landscape was consistent with examination of entire 128 chambers on the transect or the 32 subset chambers. Significantly lowering the antecedent moisture content of soil by drying eliminated the freeze-thaw emission of N2O, despite the addition of nitrate to the soil. This was linked to drying slightly reducing the denitrifying enzyme activity (DEA) of soil. The highest and earliest freeze-thaw emission of N2O was from the Riparian zone, associated with its high antecedent moisture content, DEA and total organic C content. The addition of nitrate to soil before freezing failed to enhance freeze-thaw emission of N2O from the Upper, Middle and Lower slope positions, but increased emission three-fold for the Riparian zone. Despite the greater potential of the Riparian zone to produce N2O at thaw compared to the Upland slopes, there was no spring-thaw emission of N2O from the zone on the field. This was because this zone did not freeze over the winter, due to insulation by high and persistent snow cover, vegetation and saturated condition. The denitrifying potential and freeze-thaw N2O emission increased in going from the Upper to the Lower slope position, similar to the pattern of N2O emission observed on the field. The localization of hotspots for N2O and CH4 emission within the landscape was therefore found to be driven by soil moisture and C availability. When estimating GHG emission from soil, higher emission index for N2O and CH4 should be given to poorly-drained cropped and vegetated areas of the landscape, respectively. The high potential of the Riparian zone for spring-thaw emission of N2O should not be discountenanced when conducting annual inventory of N2O emission at the landscape scale. When fall soil moisture is high, snow cover is low, and winter temperature is very cold, freeze-thaw emission of N2O at the Riparian zones of the Prairie pothole region may be very high. / May 2007
142

Three Essays on the Economics of Climate Change and the Electricity Sector

To, Hong Thi-Dieu 28 September 2011 (has links)
This doctoral thesis contains three essays on the economics of climate change and the electricity sector. The first essay deals with the subject of greenhouse gas (GHG) emissions and economic growth. The second essay addresses the issues of climate change policies, especially the role of the emergent innovative technologies, and the restructuring of the electricity sector. The third essay presents a model of transmission investments in electric power networks. Chapter One studies the impacts of climate change on economic growth in the world economies. The paper contains explicit formalization of the depletion process of exhaustible fossil fuels and the phase of technology substitution. The impacts of climate change on capital flows and welfare across countries are also investigated. The restructuring of the electricity sector is studied in Chapter Two. It also analyzes how climate change policies can benefit from emergent innovative technologies and how emergent innovative technologies can lower GHG emissions. It is shown that the price of electricity is strictly rising before emergent innovative firms with zero GHG emissions enter the market, but strictly declining as the entry begins. In Chapter Three, a model of electricity transmission investments from the perspective of the regulatory approach is formulated. The Mid-West region of Western Australia, a sub-system of the South West Interconnected System is considered. In contrast with most models in the literature that deal only with network deepening, this model deals with both network deepening and network widening. Moreover, unlike the conventional investment models which are static and deal only with the long run, this model is dynamic and focuses on the timing of the infrastructure investments. The paper is a study of an optimal transmission investment program which is part of the optimal investment program for an integrated model in which investments in transmission and investments in generation are made at the same time.
143

Phytoremediation of Nitrous Oxide: Expression of Nitrous Oxide Reductase from Pseudomonas Stutzeri in Transgenic Plants and Activity thereof

Wan, Shen 01 February 2012 (has links)
As the third most important greenhouse gas, nitrous oxide (N2O) is a stable greenhouse gas and also plays a significant role in stratospheric ozone destruction. The primary anthropogenic source of N2O stems from the use of nitrogen in agriculture, with soils being the major contributors. Currently, the annual N2O emissions from this “soil–microbe-plant” system is more than 2.6 Tg (one Tg equals a million metric tons) of N2O-N globally. My doctoral studies aimed to explore innovative strategies for N2O mitigation, in the context of environmental microbiology’s potential contribution to alleviating global warming. The bacterial enzyme nitrous oxide reductase (N2OR), naturally found in some soils, is the only known enzyme capable of catalyzing the final step of the denitrification pathway, conversion of N2O to N2. Therefore, to “scrub” or reduce N2O emissions, bacterial N2OR was heterologously expressed inside the leaves and roots of transgenic plants. Others had previously shown that the functional assembly of the catalytic centres (CuZ) of N2OR is lacking when only nosZ is expressed in other bacterial hosts. There, coexpression of nosZ with nosD, nosF and nosY was found to be necessary for production of the catalytically active holoenzyme. I have generated transgenic tobacco plants expressing the nosZ gene, as well as tobacco plants in which the other four nos genes were coexpressed. More than 100 transgenic tobacco lines, expressing nosZ and nosFLZDY under the control of rolD promoter and d35S promoter, have been analyzed by PCR, RT-PCR and Western blot. The activity of N2OR expressed in transgenic plants, analyzed with the methyl viologen-linked enzyme assay, showed detectable N2O reducing activity. The N2O-reducing patterns observed were similar to that of the positive control purified bacterial N2OR. The data indicated that expressing bacterial N2OR heterologously in plants, without the expression of the accessory Nos proteins, could convert N2O into inert N2. This suggests that atmospheric phytoremediation of N2O by plants harbouring N2OR could be invaluable in efforts to reduce emissions from crop production fields.
144

Environmental protection and energy conservation : Hybrid vehicles and combustion vehicles

Bin, Lin, Cao, Yue, Liang, Li January 2013 (has links)
Purpose/aim This study is about environmental protection and energy conservation in the China vehicle market. Based on that, we focus on and comparison of combustion vehicles with hybrid vehicles.Design/method/approach Data was collected through questionnaire. The analysis includes a description of the sample and chi-square tests. We analyze two different particular engines (combustion engine vehicles and hybrid electric vehicles) and our single environment. We compare these two engine vehicles, and analyze the trends of the market. We use scientific data and existing theories to analyze the vehicles, including “lifecycle costs” “CO2 emissions”, “Greenhouse gas”, “Consumers perception”, “Full Costing”, “PPC (Production Possibilities Curve)”, “Supply Demand Curve”, and “Green Taxes”.Findings We conclude that hybrid engine vehicles are environmentally friendly and energy conserving, but they have higher lifecycle costs. The analysis also shows that different ages, education levels and regions affect the customers’ preferences for these two kinds of vehicles.Originality/value Our original idea is the problems of hybrid vehicles and how to support and popularize hybrid vehicles depends on the exact national conditions and policies implemented. However, consumers might not be able to accept the “environmental protection and energy conservation” concept immediately, because it’s difficult to change the consumption concept of a generation or culture. Therefore, the government should carry out policies that are suitable for their local region to update the consumption concepts of the consumers and promote the new energy vehicles. Thus, the goal of environmental protection and energy conservation can be reached.
145

Development of Optimal Energy Infrastructures for the Oil Sands Industry in a CO₂-constrained World

Ordorica Garcia, Jesus Guillermo January 2007 (has links)
Western Canadian bitumen is becoming a predominant source of energy for North American markets. The bitumen extraction and upgrading processes in the oil sands industry require vast quantities of energy, in the form of power, H2, steam, hot water, diesel fuel, and natural gas. These energy commodities are almost entirely produced using fossil feedstocks/fuels, which results in significant CO2 atmospheric emissions. CO2 capture and storage (CCS) technologies are recognized as viable means to mitigate CO2 emissions. Coupling CCS technologies to H2 and power plants can drastically reduce the CO2 emissions intensity of the oil sands industry. The CO2 streams from such plants can be used in Enhanced Oil Recovery, Enhanced Coal Bed Methane, and underground CO2 storage. The above CO2 sinks currently exist in Alberta and roughly half of its territory is deemed suitable for geological storage of CO2. This study investigates the relationship between energy demands, energy costs and CO2 emissions associated with current and proposed oil sands operations using various energy production technologies. Accordingly, two computer models have been developed to serve as energy planning and economic optimization tools for the public and private sectors. The first model is an industry-wide mathematical model, called the Oil Sands Operations Model (OSOM). It serves to quantify the demands for power, H2, steam, hot water, process fuel, and diesel fuel of the oil sands industry for given production levels of bitumen and synthetic crude oil (SCO), by mining and/or thermal extraction techniques. The second model is an optimal economic planning model for large-scale energy production featuring CCS technologies to reduce CO2 emissions in the oil sands industry. Its goal is to feasibly answer the question: What is the optimal combination of energy production technologies, feedstocks, and CO2 capture processes to use in the oil sands industry that will satisfy energy demands at minimal cost while attaining CO2 reduction targets for given SCO and bitumen production levels? In 2003, steam, H2, and power production are the leading sources of CO2 emissions, accounting for approximately 80% of the total emissions of the oil sands industry. The CO2 intensities calculated by the OSOM range from 0.080 to 0.087 tonne CO2 eq/bbl for SCO and 0.037 tonne CO2 eq/bbl for bitumen. The energy costs in 2003 are $13.63/bbl and $5.37/bbl for SCO and bitumen, respectively. The results from the OSOM indicate that demands for steam, H2, and power will catapult between 2003 and 2030. Steam demands for thermal bitumen extraction will triple between 2003-2012 and triple again between 2012-2030. The H2 demands of the oil sands industry will triple by 2012 and grow by a factor of 2.7 thereafter. Power demands will roughly double between 2003 and 2012 and increase by a factor of 2.4 by 2030. The optimal energy infrastructures featured in this work reveal that natural gas oxyfuel and combined-cycle power plants plus coal gasification H2 plants with CO2 capture hold the greatest promise for optimal CO2-constrained oil sands operations. In 2012, the maximum CO2 reduction level attainable with the optimal infrastructure is 25% while in 2030 this figure is 39% with respect to “business as usual” emissions. The optimal energy costs at maximum CO2 reduction in 2012 are $21.43/bbl (mined SCO), $22.48/bbl (thermal SCO) and $7.86/bbl (bitumen). In 2030, these costs are $29.49/bbl (mined SCO), $31.03/bbl (thermal SCO), and $10.32/bbl (bitumen). CO2 transport and storage costs account for between 2-5% of the total energy costs of SCO and are negligible in the case of bitumen. The optimal energy infrastructures are mostly insensitive to variations in H2 and power plant capital costs. The energy costs are sensitive to changes in natural gas prices and insensitive to changes in coal prices. Variations in CO2 transport and storage costs have little impact on SCO energy costs and a null impact on bitumen energy costs. Likewise, all energy costs are insensitive to changes in the length of the CO2 pipeline for transport.
146

Nitrous Oxide Production in the Grand River, Ontario, Canada: New Insights from Stable Isotope Analysis of Dissolved Nitrous Oxide

Thuss, Simon Joseph January 2008 (has links)
Nitrous oxide (N₂O) is a powerful greenhouse gas, and its atmospheric concentration is increasing dramatically. N₂O is produced through the microbially-mediated processes of nitrification and denitrification. Since these processes have different substrates and isotopic enrichment factors, stable isotope analysis (δ¹⁵N and δ¹⁸O) of N₂O can be used to study the production of this important greenhouse gas. Although production in rivers accounts for a significant portion of the global N₂O budget, the isotopic composition of N₂O from this source is poorly characterized. Most of the previous work using stable isotopes of N₂O has been conducted in terrestrial or oceanic environments, and only one published study has measured δ¹⁵N and δ¹⁸O of N₂O produced in a riverine environment. The purpose of this research project was to use stable isotope analysis to characterize the processes responsible for N₂O production in the Grand River, Ontario, Canada, and to determine the spatial and temporal variability of the isotopic composition of the N₂O flux. To meet the study objectives, an offline “purge and trap” method was developed to collect and purify dissolved N₂O for stable isotope analysis. Using this method, δ¹⁵N and δ¹⁸O analysis of dissolved N₂O is possible for samples with concentrations as low as 6 nmol N₂O/L. Due to the isotopic effects of gas exchange and the back flux of tropospheric N₂O, there is a complex relationship between the δ¹⁵N and the δ¹⁸O of source, dissolved, and emitted N₂O in aquatic environments. A simple box model (SIDNO – Stable Isotopes of Dissolved Nitrous Oxide) was developed to properly interpret isotopic data for dissolved N₂O. Using this model, it was determined that the isotopic composition of emitted N₂O is much more representative of N₂O production in aquatic environments than the isotopic composition of dissolved N₂O. If the concentration, δ¹⁵N and δ¹⁸O of dissolved N₂O are measured, the magnitude and isotopic composition of the N₂O flux can be calculated. Sampling downstream of the major wastewater treatment plants (WWTPs) on the Grand River indicates that nitrification and denitrification in the river are strongly tied to diel changes in dissolved oxygen (DO) concentration. During the day, when DO concentrations are high, nitrification or nitrifier-denitrification is the dominant N₂O production pathway, with sediment denitrification also contributing to N₂O production. At night, when DO concentrations are low, denitrification in the sediments and at the sediment / water interface is the dominant production pathway. Using the SIDNO model, N₂O produced during the day was found to have a δ¹⁵N of -22‰ and a δ¹⁸O of 43‰. N₂O produced at night had a δ¹⁵N of -30‰ and a δ¹⁸O of 30‰. The isotopic composition of N₂O emitted from the Grand River is dominated by night-time production downstream of the Waterloo and Kitchener WWTPs during the summer. The flux and time weighted annual average isotopic composition of N₂O emitted from the Grand River is -18.5‰ and 32.7‰ for δ¹⁵N and δ¹⁸O respectively. These values are significantly more depleted than the only other published data for riverine N₂O production. If the Grand River is representative of global riverine N₂O production, these results will have significant implications for the global isotopic budget for atmospheric N₂O.
147

Defense and Civilian Energy Systems: Security, Sustainability and Survivability Considerations for the 21st Century

Lam, Danny 11 September 2013 (has links)
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
148

Utsläpp av växthusgaser och ammoniak från hemkomposter / Emissions of greenhouse gases and ammonia from home composts

Kempe, Björn January 2011 (has links)
Hemkompostering är fördelaktigt bland annat därför att det kan leda till minskade transporter av sopor och därmed koldioxidutsläpp, samt att den färdiga komposten kan användas som näringstillskott för växter. Kompostering av matavfall innebär dock en risk för bildning av metan och lustgas, vilka är starka växthusgaser. Även ammoniak, med försurande och övergödande effekter, kan släppas ut från komposten under vissa förhållanden. Det här arbetet syftar till att undersöka utsläppen av dessa ämnen, samt öka kunskapen om hur skötseln av komposten påverkar utsläppen.   Vid tre tillfällen under juni och juli 2010 utfördes mätningar på 20 komposter i Uppsala.  Temperaturen mättes i komposten, prov togs av gasen i kompostoch prover av materialet togs även för analys av vattenhalt, pH och askhalt. Hushållen förde också protokoll över sin skötsel av komposten under tiden för mätningarna. Utöver detta genomfördes en enkätstudie i vilken ett större antal komposter inkluderades, i avsikt att ge en bredare bild av hur hemkomposter i allmänhet sköts.   Gasproven analyserades i gaskromotograf, och de beräknade koncentrationerna relaterades till uppmätta temperaturer, vattenhalter, pH-värden och askhalter samt de ifyllda protokollen.   Enkätstudien visade att hemkomposter används och sköts om på mycket varierande sätt. Resultaten visade vidare att utsläppen av metan och lustgas (angivna som kvoterna CH4:CO2 respektive N2O:CO2) överlag var låga jämfört med uppmätta utsläpp i andra studier, med högre värden på omkring 2,5% endast för ett fåtal komposter. Effekterna av utsläppen av N2O beräknades till cirka 12 gånger större än de orsakade av utsläppen av CH4. Ett antydan till samband kunde ses mellan uppmätt NH3-halt och tillsatser av kväverikt kött-/fiskavfall. I övrigt kunde inga andra distinkta samband mellan skötsel och utsläpp observeras, något som skulle kunna bero på dels att endast tre mätomgångar ingår i studien och dels på att datan inhämtad från protokollen varierade i kvalitet och innehöll stora osäkerheter. / Home composting is beneficial as it can help reduce transports of household waste, and also because the mature compost can be used as a soil amendment for plants. On the other hand, composting of food waste enables formation of the potent greenhouse gases methane and nitrous oxide. It is also possible that ammonia be formed, which can have acidifying and eutrophicating effects on the environment. The aim of this study was to examine the emissions of these compounds, and if possible to gain knowledge on how the management of the compost affects these emissions.   Measurements were carried out on 20 home composts within Uppsala on three occasions during June and July in 2010. The compost temperature was measured, gas samples were taken and also samples of the material for analysis of moisture and ash content as well as pH. The households were also asked to fill in a protocol with all the compost activities performed during the period of the measurements. In addition to this, a questionnaire study was conducted in order to give an overview of how home composts in general are fed and managed.   The gas samples were analyzed in a gas chromatograph, and the obtained concentrations were then put in relation to the measured temperatures, pH, and moisture and ash contents as well as the data from the protocols.   The questionnaire study showed that home composts are used and managed in very different ways. Moreover, the results showed that the emissions of methane and nitrous oxide (given as CH4:CO2 and N2O:CO2 ratios) in general were small compared to those from other studies, with only a couple of composts with higher ratios than around 2.5%. The effects on the environment from the measured emissions of N2O were calculated to 12 times greater than those given by the emissions of CH4. Regarding ammonia, a clear connection was observed between the few elevated concentrations and additons of meaty waste rich of nitrogen. As for the greenhouse gases, no distinct correlations could be seen between how the composts were managed and the CH4:CO2 and N2O:CO2 ratios. This might be explained by the fact that only three sampling rounds were conducted, but also that the protocol information contained uncertainties and varied in quality.
149

Post Kyoto Protocol International Frameworks on Greenhouse-Gas Emissions: Does the Presence of Informal Economies Limit their Efficacy?

Jones, Cody January 2012 (has links)
This paper examines the informal economy’s greenhouse-gas (GHG) emissions and whether it poses a problem to the effectiveness of international frameworks designed to reduce GHG emissions. With the results of a literature review conducted on the relation between the informal economy and regulations and results on 160 nations’ theoretical informal-economy emissions over time, this paper finds that the informal economy does hinder the ability of governments to manage GHG emissions. This paper then discusses how this aspect of the world’s economy limits the efficacy of international frameworks to reduce GHG emissions. Suggestions are made on how to incorporate this sector into the proposed frameworks. The paper concludes with summarizing the main findings and proposals for further research.
150

Development of Optimal Energy Infrastructures for the Oil Sands Industry in a CO₂-constrained World

Ordorica Garcia, Jesus Guillermo January 2007 (has links)
Western Canadian bitumen is becoming a predominant source of energy for North American markets. The bitumen extraction and upgrading processes in the oil sands industry require vast quantities of energy, in the form of power, H2, steam, hot water, diesel fuel, and natural gas. These energy commodities are almost entirely produced using fossil feedstocks/fuels, which results in significant CO2 atmospheric emissions. CO2 capture and storage (CCS) technologies are recognized as viable means to mitigate CO2 emissions. Coupling CCS technologies to H2 and power plants can drastically reduce the CO2 emissions intensity of the oil sands industry. The CO2 streams from such plants can be used in Enhanced Oil Recovery, Enhanced Coal Bed Methane, and underground CO2 storage. The above CO2 sinks currently exist in Alberta and roughly half of its territory is deemed suitable for geological storage of CO2. This study investigates the relationship between energy demands, energy costs and CO2 emissions associated with current and proposed oil sands operations using various energy production technologies. Accordingly, two computer models have been developed to serve as energy planning and economic optimization tools for the public and private sectors. The first model is an industry-wide mathematical model, called the Oil Sands Operations Model (OSOM). It serves to quantify the demands for power, H2, steam, hot water, process fuel, and diesel fuel of the oil sands industry for given production levels of bitumen and synthetic crude oil (SCO), by mining and/or thermal extraction techniques. The second model is an optimal economic planning model for large-scale energy production featuring CCS technologies to reduce CO2 emissions in the oil sands industry. Its goal is to feasibly answer the question: What is the optimal combination of energy production technologies, feedstocks, and CO2 capture processes to use in the oil sands industry that will satisfy energy demands at minimal cost while attaining CO2 reduction targets for given SCO and bitumen production levels? In 2003, steam, H2, and power production are the leading sources of CO2 emissions, accounting for approximately 80% of the total emissions of the oil sands industry. The CO2 intensities calculated by the OSOM range from 0.080 to 0.087 tonne CO2 eq/bbl for SCO and 0.037 tonne CO2 eq/bbl for bitumen. The energy costs in 2003 are $13.63/bbl and $5.37/bbl for SCO and bitumen, respectively. The results from the OSOM indicate that demands for steam, H2, and power will catapult between 2003 and 2030. Steam demands for thermal bitumen extraction will triple between 2003-2012 and triple again between 2012-2030. The H2 demands of the oil sands industry will triple by 2012 and grow by a factor of 2.7 thereafter. Power demands will roughly double between 2003 and 2012 and increase by a factor of 2.4 by 2030. The optimal energy infrastructures featured in this work reveal that natural gas oxyfuel and combined-cycle power plants plus coal gasification H2 plants with CO2 capture hold the greatest promise for optimal CO2-constrained oil sands operations. In 2012, the maximum CO2 reduction level attainable with the optimal infrastructure is 25% while in 2030 this figure is 39% with respect to “business as usual” emissions. The optimal energy costs at maximum CO2 reduction in 2012 are $21.43/bbl (mined SCO), $22.48/bbl (thermal SCO) and $7.86/bbl (bitumen). In 2030, these costs are $29.49/bbl (mined SCO), $31.03/bbl (thermal SCO), and $10.32/bbl (bitumen). CO2 transport and storage costs account for between 2-5% of the total energy costs of SCO and are negligible in the case of bitumen. The optimal energy infrastructures are mostly insensitive to variations in H2 and power plant capital costs. The energy costs are sensitive to changes in natural gas prices and insensitive to changes in coal prices. Variations in CO2 transport and storage costs have little impact on SCO energy costs and a null impact on bitumen energy costs. Likewise, all energy costs are insensitive to changes in the length of the CO2 pipeline for transport.

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