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Nonrenewable Energy Chapter 15 Total World Energy Consumption - 2013 *Fossil Fuel 78.4% *Petroleum Renewable 19% *Coal *Natural Gas Nuclear 2.6% Worldwide Energy Use by Source Nonrenewable energy resources (81%) • Fossil fuels (oil, natural gas, coal) • Nuclear energy Renewable Energy Sources (19%): • Direct solar energy • Wind, hydropower, biomass (indirect solar) Energy Use in the United States Oil Sand and the Keystone XL Pipeline OPEC Controls Most of the World’s Oil Supplies Oil reserves – identified deposits from which conventional oil can be extracted OPEC (Organization of Petroleum Exporting Countries) • Algeria, Angola, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates, Venezuela • 60% of world’s crude oil reserves • 75% of reserves are government controlled – private companies are bit players (Exxon/Mobil, etc.) Oil production/flow controls rates to consumers: • Higher prices for products made with petrochemicals • Higher food prices • Airfares higher CRUDE (Conventional) OIL Crude oil, (conventional, light oil) – a thick, gooey liquid that comes from the ground Contains: • Hundreds of different combustible hydrocarbons • Small amounts of S, O, N Extracted: • Drilling a well into deposit; pumping oil out HEAVY OIL from SAND Oil Sand, – a mixture of water, clay, sand and bitumen Bitumen - Combustible hydrocarbon with high amounts of S Extracted: More oil from sand than oil in Saudi Arabia HEAVY OIL from SAND Oil Sand, – a mixture of water, clay, sand and bitumen Bitumen - Combustible hydrocarbon with high amounts of S Extracted: • By removing overburden of forest • Surface mining More oil from sand than oil in Saudi Arabia Natural Capital: Important Nonrenewable Energy Resources OIL AND NATURAL GAS COAL Oil storage Contour strip mining Oil drilling platform Geothermal power plant Oil well Pipeline Gas well Mined coal Pipeline Area strip mining Drilling tower Pump Deposits of crude oil and natural gas are trapped together under a dome deep within earth’s crust on land or under sea floor. Coal seam Water penetrates down through the rock Fig. 15-2, p. 372 CRUDE (Conventional) OIL Crude oil, or conventional oil, or light oil – a thick, gooey liquid that comes from the ground Contains? • Hundreds of different combustible hydrocarbons • Small amounts of S, O, N Formed? • From decaying fossil remains • 100-500 MYA CRUDE (Conventional) OIL Found? • Deep in the earth’s crust • Under the ocean floor Extracted? • Drilling a well into deposit; pumping oil out Products? • Petrochemicals • Gasoline CRUDE (Conventional) OIL Found? • Deep in the earth’s crust • Under the ocean floor Extracted? • Drilling a well into deposit; pumping oil out Products? • Petrochemicals • Gasoline CRUDE (Conventional) OIL Countries with majority reserves? • Saudi Arabia • Venezuela Production in U.S.? • 10% Used by U.S.? • 21% HEAVY OIL from SAND Oil Sand, – a mixture of water, clay, sand and bitumen Bitumen contains? • Combustible hydrocarbons • High amounts of S HEAVY OIL from SAND Found? • Beneath boreal forests of Canada Extracted? • By removing overburden of forest • Surface mining Products? • Synthetic crude oil HEAVY OIL from SAND Countries with majority reserves? • Canada More oil than in Saudi Arabia • Venezuela Environmental issues with extracting? • • • • Deforestation Drain wetlands; divert streams Toxic sludge Tailings stored in ponds HEAVY OIL from SHALE ROCK Oil Shale – oily shale rock that contains kerogens Kerogens contain? • Combustible hydrocarbons HEAVY OIL from SHALE ROCK Found? • Shale rock formations Extracted? • Surface mining Products? • Gasoline, heating oil • Natural gas • Other petrochemicals HEAVY OIL from SHALE ROCK Countries with majority reserves? • U.S. Environmental issues with extracting? • Land disruption • Large water usage • Air emissions HEAVY OIL from SHALE ROCK HEAVY OIL from SHALE ROCK Oil Shale – oily shale rock that contains kerogens Kerogens (combustible hydrocarbons) Science: Refining Crude Oil Natural gas Fractional Distillation Solvents Fig. 15-4a, p. 375 Science: Refining Natural Gas Is a Useful and CleanCrude Oil Burning Fossil Fuel http://www.youtube.com/watch?v=26AN1LfbUPc Keystone XL and Oil Sand Pipeline the Keystone XL Pipeline KeystoneGas XL Pipeline Natural Is a Useful and CleanBurning Fossil Fuel http://news.yahoo.com/katie-couric-explains-theclash-over-the-keystone-xl-pipeline-171519752.html Oil Sand and the Keystone XL Pipeline Proposed pipeline to link oil sands of Alberta, Canada to refineries in Texas Permit denied to build the pipeline in 2012 Oil Sand and the Keystone XL Pipeline Arguments for: • Reliable supply of oil close to U.S. • Better than transporting by truck or rail Arguments against: • Environmental costs of oil sand mining • Pipeline would cross Ogallala Aquifer NATURAL GAS Natural Gas – a mixture of gases, mainly methane Contains: • Combustible gases: • Methane (CH4) • Ethane (C2H6) • Propane (C3H8) • Butane (C4H10) • H2S NATURAL GAS Found? • Above crude oil reserves • Within shale rock Extracted? • By drilling into deposit • Hydraulic fracturing (fracking) of shale NATURAL GAS Hydraulic Fracturing Technique NATURAL GAS The Fracking Song NATURAL GAS Products? • Purified methane (in pipelines) • LPG (liquefied petroleum gas-ethane,propane,butane) • LNG (liquefied natural gas-methane) Shipped Stored in tanks LPG overseas Natural Gas Is a Useful and CleanBurning Fossil Fuel Propane and butane are liquified, removed as LPG (liquified petroleum gas) and distributed in tanks to be used in rural areas that do not have access to pipeline Remainder (mostly methane) is dried, purified, and pumped into pipelines as conventional natural gas Conventional NG (methane) can be liquified as LNG (liquified natural gas) in refrigerated tanker ships for transport overseas • Re-gasified at destination and distributed in pipelines NATURAL GAS Country with majority reserves? • Russia Used by U.S.? • 21% COAL Coal, or solid fossil fuel; most abundant fossil fuel Contains? • Mostly carbon • Small amounts of S, N • Toxic Hg COAL Formed? • From remains of plants • 300-400 MYA Found? • In the earth’s crust Extracted? • Surface mining • Subsurface mining COAL Major uses? • Generate electricity • Burned to smelt iron • Produce SNG (synthetic natural gas) – gasified coal • Synthetic gasoline or methanol – liquefied coal COAL Countries with majority reserves? • U.S. • Russia, India, China Used by U.S.? • 10% Used by China? • 50% COAL Subsurface Mining Nuclear Fission NUCLEAR ENERGY Nuclear Fission Reaction Sample Half-life Problem Approximately what fraction of a sample of radon (half-life 4 days) will remain after 4 weeks? 4 weeks = 28 days = 7 half-lifes (½)7 = 1/27 = 1/128 1/128 of the original sample remains Decommissioning of reactor Fuel assemblies 3 Enrichment Fuel fabrication of UF6 2 Conversion of U3O8 to UF6 1 5 Reactor (conversion of enriched UF6 to UO to UO2 and fabrication of fuel assemblies) Uranium-235 as UF6 Plutonium-239 as PuO2 Temporary storage of spent fuel assemblies underwater or in dry casks 4 Spent fuel reprocessing Low-level radiation with long half-life The Nuclear Fuel Cycle Open fuel cycle today Recycling of nuclear fuel Geologic disposal of moderate- and high-level radioactive wastes Fig. 15-19, p. 389 What Is the Nuclear Fuel Cycle? 1. Mine the uranium 2. Process the uranium as fuel 3. Use it in the reactor 4. Safely store the radioactive waste 5. Decommission the reactor Light-Water-Moderated and –Cooled Nuclear Power Plant with Water Reactor Small amounts of radioactive gases Uranium fuel input (reactor core) Control rods Containment shell Heat Waste heat exchanger Turbine Generator Steam Hot coolant Pump Pump Shielding Pressure vessel Coolant Moderator Coolant passage Periodic removal and storage of radioactive wastes and spent fuel assemblies Pump Water Condenser Periodic removal and storage of radioactive liquid wastes Pump Hot water output Cool water input 1. Water boils 2. Steam turns turbine 3. Electricity generated Useful electrical energy 25%–30% Waste heat Water source (river, lake, ocean) Fig. 15-17, p. 387 How Does a Nuclear Fission Reactor Work? How Does a Nuclear Reactor Work? How Does a Nuclear Fission Reactor Work? Fuel assemblies placed in core of reactor Control rods in core absorb neutrons to regulate the rate of fission Coolant (H2O) circulates through core to remove heat (prevent meltdown) Containment shell – thick, steel-reinforced concrete walls surround the core for protection Water-filled pools or dry casks for storage of radioactive spent fuel rod assemblies After 3 or 4 Years in a Reactor, Spent Fuel Rods Are Removed and Stored in Water NUCLEAR ENERGY Reaction? • Controlled nuclear fission reaction Elements? • Uranium Found? • Earth’s crust NUCLEAR ENERGY Extracted? • Surface mining • Subsurface mining Processed? • Uranium enriched to increase concentration of fissionable 235U • Packed into pellets in fuel rods and grouped as fuel assemblies NUCLEAR ENERGY Majority of reserves? • Kazakhstan • Canada • Australia World’s electricity produced? • 16% Expected by 2025? • 12% NUCLEAR ENERGY Major problems? • Radioactive waste storage (long-term) • Radiation leaks • Safety concerns – catastrophes, terrorism Case Study: Worst Commercial Nuclear Power Plant Accident in the U.S. Three Mile Island (TMI) – PA (1979) • • • • • Nuclear reactor lost coolant Partial uncovering/melting of core Unknown amounts of radiation escaped No human casualties Led to improved safety regulations in the U.S. Case Study: Worst Nuclear Power Plant Accident in the World Chernobyl – Ukraine (1986) Explosions caused reactor roof to blow off Partial meltdown/fire for 10 days Huge radioactive cloud spread over many countries 350,000 people left their homes Impacted human health, water supply, and agriculture FUKUSHIMA: Worse than Chernobyl? Fukushima: Daiichi Nuclear Plant – Japan (2011) One reactor melted down after massive earthquake and tsunami. Fuel rods lost surrounding coolant for 4 ½ hours. Radiation leaked into surrounding ocean water. Increased risk of cancer (thyroid, breast, leukemia). FUKUSHIMA: Worse than Chernobyl? Video Clip-Fukushima Explained CO2 Emissions Per Unit of Electrical Energy Produced for Energy Sources Science Focus: Net Energy Is the Only Energy That Really Counts It takes energy to get energy Second Law of Thermodynamics – high-quality energy gets used, wasted, degraded to lower-quality energy. Net energy • Useful energy available from an energy resource minus the energy needed to find, extract, process, etc. • Expressed as net energy ratio: • energy produced/energy used Net Energy Ratios for Various Energy Systems over Their Estimated Lifetimes Will Nuclear Fusion Save Us? Nuclear fusion is nuclear change in which two isotopes of light elements (H) are forced together at extremely high temperatures until they fuse to form a heavier nucleus, releasing energy in the process Still in the laboratory phase after 50 years of research and $34 billion dollars 2006: U.S., China, Russia, Japan, South Korea, and European Union • Will build a large-scale experimental nuclear fusion reactor by 2040