Nonrenewable Energy Sources Mined coal Pipeline Pump Oil well Gas well Oil storage Coal Oil and Natural Gas Geothermal Energy Hot water storage Contour strip mining Drilling tower Magma Hot rock Natural gas Oil Impervious rock Water Floating oil drilling platform Valves Underground coal mine Water is heated and brought up as dry steam or wet steam penetrates down through the rock Area strip mining Geothermal power plant Coal seam Oil drilling platform on legs

Nature and Formation of Mineral Resources Existence Decreasing certainty Known Decreasing cost of extraction Other resources Reserves Undiscovered Identified Not economical Economical

Kilocalories per Person per Day Society Kilocalories per Person per Day Modern industrial (United States) 260,000 Modern industrial (other developed nations) 130,000 Early industrial 60,000 Advanced agricultural 20,000 Early agricultural 12,000 Hunter– gatherer 5,000 Primitive 2,000

Evaluating Energy Resources Renewable energy Nuclear power 6% Hydropower, geothermal, Solar, wind 7% Non-renewable energy Natural Gas 23% Future availability Biomass 12% Coal 22% Net energy yield Oil 30% Cost World Environmental effects

North American Energy Resources Coal Gas Oil High potential areas MEXICO UNITED STATES CANADA Pacific Ocean Atlantic Grand Banks Gulf of Alaska Valdez ALASKA Beaufort Sea Prudhoe Bay Arctic Prince William Sound Arctic National Wildlife Refuge Trans Alaska oil pipeline

100 Wood Coal 80 60 Natural gas Oil 40 Hydrogen Solar 20 Nuclear 1800 Contribution to total energy consumption (percent) Oil 40 Hydrogen Solar 20 Nuclear 1800 1875 1950 2025 2100 Year

Coal Formation

Removing Nonrenewable Mineral Resources Surface mining Subsurface mining Strip mining Open-pit Mountain Top Removal

Underground Coal Mine

Burning Coal More Cleanly Calcium sulfate and ash Air Air nozzles Water Fluidized bed Steam Flue gases Coal Limestone Fluidized-Bed Combustion

Oil Petroleum (crude oil) Petrochemicals Refining Transporting Gases Diesel oil Asphalt Grease and wax Naphtha Heating oil Aviation fuel Gasoline Gases Furnace Heated crude oil Petroleum (crude oil) Petrochemicals Refining Transporting

Opec countries Saudi Arabia (11.9%), Iran (5.1%), Venezuela (4.7%), Iraq (3.6%), United Arab Emirates (3.2%), Nigeria (2.9), Libya (2%), Indonesia (2%), Algeria (1.6%), Qatar (1%) Non-Opec countries United States (10.3%), Russia (8.8%), Mexico (4.8%), China (4.6%), Norway (4.3%), UK (4%), Canada (3.5%) (Percentages of world oil output)

40 2,000 x 109 barrels total 30 (x 109 barrels per year) Annual production 20 10 1900 1925 1950 1975 2000 2025 2050 2075 2100 Year World

Advantages Disadvantages Ample supply for 42–93 years Need to find substitute within 50 years Low cost (with huge subsidies) Artificially low price encourages waste and discourages search for alternatives High net energy yield Easily transported within and between countries Air pollution when burned Low land use Releases CO2 when burned Moderate water pollution

Shale oil pumped to surface Oil Shale Above Ground Conveyor Spent shale Pipeline Retort Mined oil shale Air compressors Shale oil storage Impurities removed Hydrogen added Crude oil Refinery injection Shale layer Underground Sulfur and nitrogen compounds Shale oil pumped to surface Shale heated to vaporized kerogen, which is condensed to provide shale oil

Tar Sands Tar sand is mined. Tar sand is heated until bitumen floats to the top. Bitumen vapor Is cooled and condensed. Pipeline Impurities removed Hydrogen added Synthetic crude oil Refinery Tar Sands

Natural Gas 50-90% methane Approximate 200 year supply

Advantages Disadvantages Ample supplies (125 years) Releases CO2 when burned High net energy yield Methane (a greenhouse gas) can leak from pipelines Low cost (with huge subsidies) Shipped across ocean as highly explosive LNG Less air pollution than other fossil fuels Sometimes burned off and wasted at wells because of low price Lower CO2 emissions than other fossil fuels Moderate environ- mental impact Easily transported by pipeline Low land use Good fuel for fuel cells and gas turbines

Nuclear Energy Fission reactors Uranium-235 Potentially dangerous Periodic removal and storage of radioactive wastes and spent fuel assemblies radioactive liquid wastes Pump Steam Small amounts of Radioactive gases Water Black Turbine Generator Waste heat Electrical power Hot water output Condenser Cool water input Waste heat Useful energy 25 to 30% Water source (river, lake, ocean) Heat exchanger Containment shell Emergency core Cooling system Control rods Moderator Pressure vessel Shielding Coolant passage Hot coolant Uranium fuel input (reactor core) Uranium-235 Potentially dangerous Radioactive wastes

The Nuclear Fuel Cycle Front end Back end Uranium mines and mills Ore and ore concentrate (U3O8) Geologic disposal of moderate- and high-level radioactive wastes High-level radioactive waste or spent fuel assemblies Uranium tailings (low level but long half-life) Conversion of U3O8 to UF6 Processed uranium ore Uranium-235 as UF6 Enrichment UF6 Enriched Fuel fabrication Spent fuel reprocessing Plutonium-239 as PuO2 (conversion of enriched UF6 to UO2 and fabrication of fuel assemblies) Fuel assemblies Reactor Spent fuel assemblies Interim storage Under water Open fuel cycle today Prospective “closed” end fuel cycle Decommissioning of reactor

Advantages Disadvantages Large fuel supply High cost (even with large subsidies) Low environmental impact (without accidents) Low net energy yield High environmental impact (with major accidents) Emits 1/6 as much CO2 as coal Moderate land disruption and water pollution (without accidents) Catastrophic accidents can happen (Chernobyl) Moderate land use No acceptable solution for long-term storage of radioactive wastes and decommissioning worn-out plants Low risk of accidents because of multiple safety systems (except in 35 poorly designed and run reactors in former Soviet Union and Eastern Europe) Spreads knowledge and technology for building nuclear weapons

Dealing with Nuclear Waste Low-level waste High-level waste Underground burial Disposal in space Burial in ice sheets Dumping into subduction zones Burial in ocean mud

Up to 60 deep trenches dug into clay. As many as 20 flatbed trucks deliver waste containers daily. Barrels are stacked and surrounded with sand. Covering is mounded to aid rain runoff. Clay bottom Fig. 14.38b, p. 351

Crane for moving fuel rods Steam generator Cooling pond Turbines Almost all control rods were removed from the core during experiment. Automatic safety devices that shut down the reactor when water and steam levels fall below normal and turbine stops were shut off because engineers didn’t want systems to “spoil” experiment. Crane for moving fuel rods Emergency cooling system was turned off to conduct an experiment. Steam generator Cooling pond Turbines Radiation shields Reactor Water pumps Reactor power output was lowered too much, making it too difficult to control. Additional water pump to cool reactor was turned on. But with low power output and extra drain on system, water didn’t actually reach reactor. Fig. 14.37, p. 350