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Fossil Fuels: Their advantages, disadvantages and future. Geoffrey Thyne Enhanced Oil Recovery Institute University of Wyoming. Modern Civilization. World Energy Demand.
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Fossil Fuels: Their advantages, disadvantages and future Geoffrey Thyne Enhanced Oil Recovery Institute University of Wyoming
World Energy Demand In 1999, with less than 5 % of the world's population, the US generated 30 % of the world's GDP (Gross Domestic Product), consumed 25 % of the world's energy, and emitted 25 % of the world's carbon dioxide."
Energy Sources • Fossil fuels • Nuclear • Solar • Wind • Efficiency
US Energy Sources and Sinks • http://www.eia.doe.gov/emeu/aer/pdf/pages/sec1_3.pdf
Fossil Fuels • Oil – liquid hydrocarbon phase formed during burial between 70 and 120C from kerogen. • Natural Gas – hydrocarbons that are gaseous at earth surface conditions (C1-C4) and formed by thermal degradation of kerogen or oil, or by microbial action near surface. • Coal – Solid phase hydrocarbon formed from organic matter deposited in fresh water shallow environments (swamps).
Fossil FuelsPluses and Minuses • Highly efficient fuels with good energy density and energy return. • Large and mature infrastructure. • Major liquid reserves are not domestic. • Ultimately limited amount. • May have reached or are reaching peak oil. • Still don’t have clean coal.
For electricity, America can become self-sufficient since 76% is generated domestically from US-based coal (50%), nuclear (19%) and hydro-power (7%).
Improved technology Increased pricing Resource Triangle Conventional Reservoirs Small volumes that are easy to develop Unconventional Large volumes difficult to develop
Liquid Fuels • Almost all liquid petroleum (oil) is refined producing liquid and solid products such as gasoline, jet fuel, petrochemical feedstocks and asphalt. • Almost all liquids are used for transportation (gasoline and diesel).
Proved oil reserves BP Statistical Review of World Energy 2008
But - transportation (auto, truck, aircraft, military), plastics and food energy demands are nearly 100% dependent on oil
Most natural gas is used in home heating, electrical generation and petrochemical synthesis. So is compressed for transportation (LPG). The major current sources are conventional petroleum fields. The major future sources will be unconventional sources (coal beds, tight sandstones and shale). Gaseous Fuels
Production of Coal Bed Gas • Groundwater is removed from shallow coal beds to release natural gas (methane). • Production of water is much higher (10-100X) than traditional gas wells • (400 bbl. water = 100 MCF) • Capacity of traditional water disposal method (re-injection) is limited
Coal – the solid hydrocarbon • 6.2 billion tons annually (global) • 75% is burned to produce electricity • Distribution is fairly uniform on global scale
Coal • Formed when organic-rich sediments were buried to form peat • Further burial creates more carbon–rich forms • Lignite or brown coal, fuel only • Sub-bituminous, fuel • Bituminous, dense, black, fuel and coke • Anthracite, glossy black, heating
Using Coal Coal Carbon Based Products Electrical Generation Standard Pulverized Coal Plant Coal Gasification IGCC Coal Plant Ammonia Fertilizer Natural Gas Liquids
Coal • Emissions of toxic products • Nitrogen produces nitric acid (HNO3), NOX • Sulfur produces SO2, sulfuric acid (H2SO4), SOX • Major metal is mercury (Hg) • Produces Flyash as by-product of combustion
Using Coal • Large domestic resource • Infrastructure in place • Carbon tax will increase electricity costs • Will need “clean coal” – capture and dispose of C, N, S and Hg (Future Gen)
Demand for Energy Will Continue to RiseOil and gas provide about two-thirds of energy consumed Gas 24% Quadrillion Btu Oil 40% Year DOE EIA, Annual Energy Outlook 2004, Figure 2
Future of Petroleum Industry Development of unconventional resources (heavy oils, tar sands, gas, oil shale, coal-to-liquids) Broad implementation of EOR/IOR Big companies are diversifying into other energy sources