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Energy Use Chapter 21-22

Energy Use Chapter 21-22. Conventional Energy (Ch. 21). Fossil Fuels now provide about 85% of the world’s energy Coal Oil Natural Gas Biomass Fuels provide about 6% Wood Peat Charcoal Manure Nuclear Power provides about 5%. Sustainable Energy (Ch.22). Renewable Resources produce 4%

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Energy Use Chapter 21-22

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  1. Energy UseChapter 21-22

  2. Conventional Energy (Ch. 21) • Fossil Fuels now provide about 85% of the world’s energy • Coal • Oil • Natural Gas • Biomass Fuels provide about 6% • Wood • Peat • Charcoal • Manure • Nuclear Power provides about 5%

  3. Sustainable Energy (Ch.22) • Renewable Resources produce 4% • Solar • Wind • Geothermal • Hydro

  4. Consumption • The 20 richest countries consume : • 80% of the natural gas • 65% of the oil • 50% of the coal • The United States consists of 4% of the world’s population but consumes about 25% of the available energy

  5. Energy Use in the U.S. • 38% used by industry • Fuel • Plastics • Chemicals • Raw materials for buildings • Paper • 36% is residential • 25% Mining, milling, smelting, and forging of metal ore

  6. Efficiency? • The problem with our conventional forms of energy is that half of the potential energy is lost when converting it into more usable forms • Coal – about 75% is lost • Oil – about 75% is lost • Natural Gas- only about 10% is lost • Also is best for the atmosphere

  7. COAL PRODUCTION

  8. Coal • The energy we get from coal today is the energy plants absorbed from the sun millions of years ago • Plant matter washed into the bottoms of swamps and later buried under sediment • Under heat and pressure this material changed physically and chemically into coal

  9. Types of Coal • Coal is classified based upon the % of carbon, hydrogen, and oxygen • The higher the carbon content the more efficient it is • Lignite – 25-35% carbon • Bituminous – 45-86% carbon • Anthracite – 86-97% carbon

  10. Coal Mining • Coal can be mined in two different ways • Surface Mining or Strip Mining • Underground Mining • Surface Mining is used when a coal seam is within 200’ of the surface • Underground mining is used below 200’

  11. Surface Mining • First soil and overburden must be removed • Coal is then extracted • Overburden is replaced, covered with topsoil and seeded (reclamation)

  12. Reclamation • Reclamation of mines is required by law and helps restore the biological balance of the area • Very difficult to enforce the reclamation • Usually flattened and planted with non-native species

  13. Underground Mining • Occasional cave-ins, and fires • Accumulation of poisonous gases • Respiratory diseases acquired later in life • 30,000 deaths in PA from 1870-1950 (1 per day)

  14. Underground Mining • Miners and machinery descend into the mine • Coal is dug from the coal face • Coal is transferred via conveyors • Finally carried up to the surface

  15. Coal and the Environment • The biggest issue is the emission of sulfur from the burning of coal • This can result in acid rain • Scrubbers are used to remove as much of the sulfur as possible • Carbon dioxide is also released contributing to the Greenhouse Effect • Radioactive material is also emitted from the burning of coal

  16. Effects of Acid Rain

  17. Clean Coal Technology • These technologies remove sulfur and other harmful chemicals from coal before, during, and after coal is burned • Heated to the point where the chemicals are absorbed by rock • Kept under a temp. at which they form pollutants • Coal can also be turned into a gas removing the harmful chemicals

  18. Summary of Coal • Still have estimated 270 years left for use • Used mainly for electricity, iron/steel manufacturing • Advantages – abundant (for now), cheap, U.S. has the largest supply • Disadvantages – Ash, Sludge (mercury, uranium, arsenic) Sulfur (acid rain), CO2, Fires, Subsidence, Reclamation of Land • How a coal fired plant works

  19. Petroleum

  20. Formation of Oil • Formed from the remains of tiny sea plants and animals that died millions of years ago. • Eventually changes due to pressure and temperature will physically and chemically change the rocks from above • 2% of organic material is turned into oil

  21. Where do we find oil? • We need to look for rocks that are porous (have a lot of pore space to contain liquids and gases) • We also need to look for rocks that are impermeable that would then trap the oils and gas from rising and dissipating

  22. Types of Oil Traps Anticline Trap Fault Trap

  23. Oil Production • Oil drilling and production are regulated by state and federal governments • Companies must get permission to explore for oil on new lands • Experts indicate that 85% of our remaining oil reserves are on land owned by the federal government • Governments receive rental payments as well as a % of the profit

  24. Oil Production • Only about 40% of wells find oil • Wells may go from 6,000 feet to 20,000 feet below the surface • Each well generally produces 11 barrels per day • 31 states produce oil • Largest- Texas, Alaska, California, Louisiana

  25. From Well to Market • Crude oil needs to go to a refinery • Usually is sent by ship, barge, pipeline, truck, or train • Refineries clean and separate oil into various fuels • Gasoline • Diesel Fuel • Heating Oil • Jet Fuel • Refineries also remove contaminants to increase efficiency and reduce air pollution • Oil is then shipped via pipelines to retailers • About 10 days for oil to travel from Texas to Illinois

  26. Imported Oil • We import 2/3 of petroleum from other countries • OPEC (Organization of Petroleum Exporting Countries) is a group that tries to set production levels for petroleum • The less oil they produce, the higher the price of oil on the world market • OPEC controls most of the oil market • The U.S. does have a 3-month supply of oil tucked away (SPR – Strategic Petroleum Reserve)

  27. Offshore Oil • There are significant deposits off the Pacific Coast and the Gulf of Mexico • Offshore drilling gives us 24% of our oil production • Much more costly than drilling on land • Embedded and Floating Drills

  28. Oil and the Environment • Drilling for oil will disturb fragile ecosystems • Transporting oil will endanger wildlife if there is a spill • Leaking storage containers can get into the groundwater • Processing oil and burning gasoline contribute to air pollution

  29. The Clean Air Act has forced refineries to reduce emissions • This Act has also forced gas companies to reformulate gasoline to burn cleaner

  30. ANWR Links • Defenders • ANWR.org

  31. Summary of Petroleum • Used mainly as a transportation fuel (gasoline, diesel, jet) and for heat (heating oil) • Advantages – Fuels entire transportation system, use in manufacturing of plastics • Disadvantages – Air Pollutants, CO2, Spills, Found in Environmentally Sensitive areas, Imported • How a combustion engine works

  32. Natural Gas

  33. What is Natural Gas? • Natural Gas is also formed from the breakdown of organic matter • Natural Gas is usually found directly above an oil deposit • The main ingredient is methane which is odorless, colorless, and tasteless

  34. Production • Wells average 6100 feet • Costs = $100 per foot • 48% of exploratory wells produce gas • Natural gas goes to a processing plant where it is cleaned and separated • Natural gas can also be produced from coal mines or from landfills

  35. Transporting and Storing • 300,000 miles of underground pipelines link wells to cleaning plants of major cities • A compressor forces the gas through the pipelines • Along the pipelines are giant reservoirs used for storage for the winter months • Eventually the gas will reach the local utility where an odorant is added and finally piped to the house

  36. Use • 2nd in energy consumption behind petroleum • 23% of the energy used in the U.S. • Industry is the biggest user • Heat for manufacturing • Also used as an ingredient for a number of products • Residence is the second biggest user • Heating, cooking, as well as electricity (cleaner than coal) • Also can be used by cars for fuel

  37. Natural Gas and the Environment • Releases pollutants into the atmosphere when burned • However, natural gas is the cleanest of the fossil fuels • Less sulfur • Less carbon • Less nitrogen • Few particles of ash emitted into the atmosphere • Produces carbon dioxide (greenhouse gas)

  38. Fracking • Fracking is a process in which water with chemicals are shot into a well in order to fracture the shale to release natural gas.

  39. Fracking has any number of chemicals that could possibly get into the groundwater.

  40. Summary of Natural Gas • Used for heating of indoor spaces and water, as a transportation fuel, or electricity • Advantages- Cleaner than coal or petroleum • Disadvantages- supply (50 years?), air pollutants, greenhouse gases • How a furnace works

  41. Nuclear Power

  42. In the 1950’s, Eisenhower bragged to the world that the U.S. would tame atomic energy and use its power to do useful work • (swords to plowshares) • In the 1970’s the U.S. ordered 140 new reactors • Costs, and safety fears made it less attractive (100 canceled) • Wind, Solar and Hydro are now cheaper than nuclear power

  43. After the Gulf War, nuclear saw a boom due to the fact of the people’s negative views of oil and its claim that nuclear was friendly due to the fact that it doesn’t emit greenhouse gases • Nuclear was then seen as a bridge to a point where we can focus on renewable resources

  44. How do they work? • Uranium – 235 is used • The isotope is cleaned and converted into pellets • Each pellet has the energy of 1 ton coal and 4 barrels of oil • Pellets are stored in rods, rods are arranged in a fuel assembly • Thousands of fuel assemblies are bundled in the reactor core.

  45. The uranium is unstable. When hit with a neutron it splits and releases energy along with other neutrons that split the other isotopes (fission) • This is called a chain reaction, which is then slowed by a cooling solution circulating around the rods (absorbs neutrons) • Control rods also monitor the chain reaction • More coolant is then added to keep the chain reaction under control

  46. PWR40,000 valves compared to 4,000 in a coal plant

  47. BWR • Radioactive water and steam leave the containment structure

  48. Meltdown • If there is a problem with the coolant or the control rods, the chain reaction produces too much heat and a meltdown can occur. • This would then release the radioactive material into the air

  49. Waste Management Mining wastes, mill tailings (200 million tons today in the U.S.), spent fuel rods Ocean Dumping – U.S., Britain, France, Japan and Russia have all dumped radioactive wastes into our oceans Land Disposal • Originally waste was to be stored underground in temporary pools until permanent storage was available • Permanent storage was not ready so it is stored in metal tanks on site • Eventually permanent sites are being planned underground until waste decays to a stable form • Yucca mountain cut off by Obama in 2009

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