The International Energy Agency (IEA) expects total natural gas output in the EU to decrease from 216 billion cubic meters per year (bcm/year) in 2006 to 90 bcm/year in 2030. For the same period, EU demand for natural gas is forecast to increase rapidly. In 2006 demand for natural gas in the EU amounted to 532 bcm/year. By 2030, it is expected to reach 680 bcm/year. As a consequence, the widening gap between EU production and consumption requires a 90% increase of import volumes between 2006 and 2030. The main sources of imported gas for the EU are Russia and Norway. Between them they accounted for 62% of the EU’s gas imports in 2006. The objective of this thesis is to assess the potential future levels of gas supplies to the EU from its two main suppliers, Norway and Russia. Scenarios for future natural gas production potential for Norway and Russia have been modeled utilizing a bottom-up approach, building field-by-field, and individual modeling has been made for giant and semi- giant gas fields. In order to forecast the production profile for an individual giant natural gas field a Giant Gas Field Model (GGF-model) has been developed. The GGF-model has also been applied to production from an aggregate of fields, such as production from small fields and undiscovered resources. Energy security in the EU is heavily dependent on gas supplies from a relatively small number of giant gas fields. In Norway almost all production originates from 18 fields of which 9 can be considered as giant fields. In Russia 36 giant fields account for essentially all gas production. There is limited potential for increased gas exports from Norway to the EU, and all of the scenarios investigated show Norwegian gas production in decline by 2030. Norwegian pipeline gas exports to the EU may even be, by 2030, 20 bcm/year lower than today’s level. The maximum increase in exports of Russian gas supplies to the EU amount to only 45% by 2030. In real numbers this means a mere increase of about 70 bcm In addition, there are a number of potential downside factors for future Russian gas supplies to the European markets. Consequently, a 90% increase of import volumes to the EU by 2030 will be impossible to achieve. From a European energy security perspective the dependence of pipeline gas imports is not the only energy security problem to be in the limelight, the question of physical availability of overall gas supplies deserves serious attention as well. There is a lively discussion regarding the geopolitical implications of European dependence on imported gas from Russia. However, the results of this thesis suggest that when assessing the future gas demand of the EU it would be of equal importance to be concerned about diminishing availability of global gas supplies.

In this study / gas production by depressurization method from a hydrate reservoir containing free gas zone below the hydrate zone is numerically modeled through 3 dimensional, 3 phase, non-isothermal reservoir simulation. The endothermic nature of hydrate decomposition requires modeling to be non-isothermal / hence energy balance equations must be employed in the simulation process. TOUGH-Fx, the successor of the well known multipurpose reservoir simulator TOUGH2 (Pruess [24]) and its very first module TOUGH-Fx/Hydrate, both developed by Moridis et.al [23] at LBNL, are utilized to model production from a theoretical hydrate reservoir, which is first studied by Holder [11] and then by Moridis [22], for comparison purposes. The study involves 2 different reservoir models, one with 30% gas in the hydrate zone (case 1) and other one with 30% water in the hydrate zone (case 2). These models are further investigated for the effect of well-bore heating. The prominent results of the modeling study are: &amp / #8226 / In case 1, second dissociation front develops at the top of hydrate zone and most substantial methane release from the hydrate occurs there. &amp / #8226 / In case 2 (hydrate-water in the hydrate zone), because a second dissociation front at the top of hydrate zone could not fully develop due to high capillary pressure acting on liquid phase, a structure similar to ice lens formation is observed. &amp / #8226 / Initial cumulative replenishment (first 5 years) and the replenishment rate (first 3.5 years) are higher for case 2 because, production pressure drop is felt all over the reservoir due to low compressibility of water and more hydrate is decomposed. Compared to previous works of Holder [11] and Moridis [22], amount of released gas contribution within the first 3 years of production is significantly low which is primarily attributed to the specified high capillary pressure function.

Air pollutants and greenhouse gases are two groups of important trace components in the earth’s atmosphere that can affect local air quality, be detrimental to the human health and ecosystem, and cause climate change. Human activities, especially the energy use and energy production processes, are responsible for a significant share of air pollutants and greenhouse gases in the atmosphere. In this work, I specifically focused on characterizing air pollutants and greenhouse gas emissions from the on-road gasoline and diesel vehicles, which is an important energy use process that largely contributes to the urban air pollutions, and from the natural gas production systems, which is a major energy production process that has increased dramatically in recent years and is expected to have a long-lasting impact in the future. We conducted multi-seasonal measurements in the Fort Pitt Tunnel in Pittsburgh, PA to update the on-road vehicle emission factors, to measure the size distribution of vehicle emitted particulate matter (PM), and to quantify the volatility distributions of the vehicle emitter primary organic aerosol (POA). We also conducted mobile measurements in the Denver-Julesburg Basin, the Uintah Basin, and the Marcellus Shale to quantify facility-level VOC emission from natural gas production facilities, and I constructed a gridded (0.1° × 0.1°) methane emission inventory of natural gas production and distribution over the contiguous US. I found that the stricter emission standards were effective on regulating NOx and PM emissions of diesel vehicles and the NOx, CO and organic carbon (OC) emissions of gasoline vehicles, while the elemental carbon (EC) emissions of gasoline vehicles did not change too much over the past three decades. Vehicle-emitted particles may be largely externally mixed, and a large fraction of vehicle-emitted particles may be purely composed of volatile component. Vehicle-emitted smaller particles (10– 60 nm) are dominantly (over 75%) composed of volatile component. The size-resolved particles and particles emission factors for both gasoline and diesel vehicles are also reported in this work. I also found that the POA volatility distribution measured in the dynamometer studies can be applied to describe gas-particle partitioning of ambient POA emissions. The POA volatility distribution measured in the tunnel does not have significant diurnal or seasonal variations, which indicate that a single volatility distribution is adequate to describe the gas-particle partitioning of vehicle emitted POA in the urban environment. The facility-level VOC emission rates measured at gas production facilities in all three gas production fields are highly variable and cross a range of ~2-3 order of magnitudes. It suggests that a single VOC emission profile may not be able to characterize VOC emissions from all natural gas production facilities. My gridded methane emission inventory over the contiguous US show higher methane emissions over major natural gas production fields compared with the Environmental Protection Agency Inventory of US Greenhouse Gas Emission and Sinks (EPA GHGI) and the Emission Database for Global Atmospheric Research, version 4.2 (Edgar v4.2). The total methane emissions of the natural gas production and distribution sector estimated by my inventory are 74% and 20% higher than the Edgar v4.2 and EPA GHGI, respectively. I also run the GEOS-Chem methane simulation with my inventory and EPA GHGI and compare with the GOSAT satellite data, and results show that my inventory can improve the model and satellite comparison, but the improvement is very limited. The size-resolved emission factors of vehicle emitted particles and POA volatility distribution reported in this work can be applied by the chemical transport models to better quantify the contribution of vehicle emissions to the PM in the atmosphere. Since our measurement of VOC emissions of natural gas production facilities were conducted before EPA started to regulate VOC emissions from the O&NG production facilities in 2016, the facility-level VOC emission rates reported in this work can serve as the basis for future studies to test the effectiveness of the regulatory policies. The spatially resolved methane emission inventory of natural gas production and distribution constructed in this work can be applied to update the current default methane emission inventory of GEOS-Chem, and the updated methane emission inventory can be used as a better a priori emission field for top-down studies that inversely estimate methane emissions from atmospheric methane observation.

[pt] Para que ocorra o fluxo de fluidos em um sistema de produção é necessário que a energia dos fluidos no reservatório seja capaz de superar as perdas de carga nos diversos componentes do sistema. Os fluidos têm que escoar do reservatório aos separadores na superfície, passando pelas tubulações de produção dos poços, pelos equipamentos de cabeça de poço e pelas linhas de surgência. O projeto de um sistema de produção não deve ser executado considerando independentemente o desempenho do reservatório e o cálculo do fluxo nas tubulações de produção e nas linhas e equipamentos de superfície. A avaliação do desempenho de um sistema de produção de gás requer a aplicação de um método de análise total que considere simultaneamente o escoamento nos diversos segmentos do sistema. A análise total de um sistema de produção, pode ser efetuada por um método gráfico - analítico a ser empregado no desenho de completação de poços de gás e petróleo com ou sem levantamento artificial. Em termos de conceito de análise total, um sistema de produção é constituído basicamente pelos elementos: reservatório, tubo de produção vertical, linhas de fluxo horizontal e separador, incluindo válvulas de fundo de poço e choke superficiais, onde ocorrem uma certa perda de pressão relacionada com a vazão. O comportamento de fluxo de cada elemento do sistema total de produção é representado por uma equação que relaciona a pressão num nó selecionado e a vazão de produção. O cálculo seqüencial das pressões nos diferentes nós dos diversos elementos do sistema permite que a vazão de produção do poço seja determinada. Para calcular a relação da vazão com as mudanças de pressão que ocorrem durante o transporte do fluido à superfície e conseqüente variação das propriedades físicas do fluido, efetuou-se uma revisão dos conceitos de engenharia de reservatório, correlações de fluxo em tubulações verticais, horizontais e restrições. Finalmente, realizou-se uma análise de sensibilidade da metodologia ao emprego das diferentes relações de performance de fluxo e dos métodos de cálculo de fluxo em poços e linhas. / [en] For the flow of fluids to occur in a production system, the fluids energy in the reservoir must be capable of overcoming load losses along various system components. Fluids must flow from the reservoir to the surface separators through the wells tubing, wellhead equipment and flowing lines. The production system design must not be executed by considering separately the performance of the reservoir and the flow calculation across the tubing, surface equipment and lines. The evaluation of a gas production system performance requires applying a total analysis method that considers the drainage at various system segments simultaneously. The total analysis of a production system can be effected through a graphical- analytical method to be used for the completion design of oil and gas wells with or without artificial lift. In terms of total analysis concept, a production system is basically comprised of the following components: reservoir, vertical tubing, horizontal flow lines and separator, including bottom-hole valves and surface choke, where some pressure loss occurs in relation to the flow rate. The flow behavior of each component in a total production system is represented by an equation that relates the pressure at one selected node and the production flow rate. The sequential pressure calculation at the different nodes of various system components allows determining the well s production flow rate. In order to calculate the relationship between the flow rate and the pressure changes that occur during fluid transportation to the surface, with the resulting variation of the fluid s engineering, flow correlations in vertical and horizontal tubing, and restrictions. Finally, we proceeded to analyze the methodology s sensitivity to the use of different flow performance relations and flow calculation methods in wells and lines.

Oil and natural gas are the most strategic raw materials to meet the expanding energy requirement in today&rsquo / s world. They have great impact on issues such as economy, national security, development, competition, and political consistency. Being a developing country, Turkey&rsquo / s natural gas requirement is increasing rapidly. However, the production is far from covering the demand. Recent assumptions point out that natural gas demand of Turkey will reach 44 billion cubic meters in 2010 with a financial burden of 10 billion $ to the national economy. Therefore Turkey requires meeting natural gas demand by using its own conventional natural gas resources. The geological researches and global data encourage Turkey to drill more exploration wells in offshore side of Western Black Sea .In early 2007, the production will be started in Western Black Sea Region with 1.42 million cubic meter gas per day. Moreover, further exploration and production activities in the region are still continuing in order to increase the production. In this thesis, issues such as importance of the natural gas for Turkey and the world, Turkey&rsquo / s present energy situation and natural gas supply and demand scenarios for Turkey have been investigated. The possible impact of natural gas exploration and production in Black Sea region on Turkey&rsquo / s economy in near future has been emphasized. An extensive literature survey using related printed and unprinted media has been performed in order to collect the necessary data and information.

My dissertation consists of three distinct but related chapters on Energy Economics and Finance. My first chapter is an empirical evaluation of market conduct in global crude oil markets. "Hotelling rule" states that even in competitive equilibrium, price of an "exhaustible resource" exceeds its marginal cost due to the opportunity cost of depleting the non-renewable resource. This cost is called "scarcity rent". Oil price exceeds its marginal extraction cost significantly. This can be attributed to two different sources: effect of scarcity of oil on prices or exercising market power by OPEC (collusion). In this paper, I use Porter (1983) approach considering the possibility of "scarcity rent" component involved in the gap between price and marginal extraction cost in the oil market. The novelty of my approach is to empirically estimate scarcity rent using data on cost of production of oil. Two benchmark cases, where scarcity rent is either zero (non-exhaustible resources hypothesis (Adelman 1990)) or equal to minimum price-cost margin are considered. The results show that in both cases OPEC failed to cooperate effectively and in second case, market conduct estimated is closer to Cournot behavior. In the second chapter of my dissertation, we employ a real options approach to evaluate oil and gas companies' investment decisions in an empirical setup. We develop a theoretical model to derive testable predictions. A unique measure of investment costs is obtained from energy industry data vendors. This novel dataset contains details of contract terms and pricing for offshore drilling equipment, which constitute the major share of investment costs in offshore oil field development. The investment database is combined with financial and macroeconomic data, which enables us to perform a panel data analysis of investments' response to variations in investment costs and market variables such as the slope of futures curve, firms' past earnings, cost of capital and implied oil price volatility. Our results show that the larger firms, facing less financial friction, are more forward looking while the smaller firms, who have less access to capital markets, are more dependent on their past earnings. The third chapter of my dissertation is about the effect of recent natural gas production boom on U.S. manufacturing. Natural gas production in North America has increased significantly over the past decade causing the prices to plunge during past 5 years. The purpose of this research is to investigate the effect of low natural gas prices on energy intensive U.S. manufacturing industries using market data. I empirically evaluate the stock market reactions of publicly traded companies in energy intensive industries to arrival of new information about the unexpected price shocks in natural gas futures markets. My results show that the stock market does not react significantly to innovations in the expected price of natural gas, proxied for by monthly changes in natural gas futures contracts with a fixed maturity date. I then split the sample into two groups based on their expenditure on natural gas as a ratio of their total production value. The stock market valuation of companies in high "natural gas intensity" industries were positively affected by unexpected downward shocks in natural gas prices and the results are significant. / text