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Do Now. Download ch.12 notes. Does anyone owe me work? Reminders: $89 due Monday (moved to next Friday) Preliminary Report due Wed Recycling permission slip due next Fri. Energy. Energy Star Program 1992, US Dept of E 2005 Energy Policy Act Improvements in energy conservation
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Do Now • Download ch.12 notes. • Does anyone owe me work? • Reminders: • $89 due Monday (moved to next Friday) • Preliminary Report due Wed • Recycling permission slip due next Fri
Energy • Energy Star Program 1992, US Dept of E • 2005 Energy Policy Act • Improvements in energy conservation • Continue development of alternative energy sources: • Hydrogen • Solar • Wind
History • Greeks 2,500ya • Burned charcoal, primary source = wood • 5th century BCE: fuel shortage • Built houses to allow more sunlight in winter, less in summer • Romans 2,000ya • Burned wood • Eventually depleted and so imported • Developed glass windows, greenhouses • Illegal to build and shade another house
Basics • Work = force x distance • Review potential vs. kinetic • Review laws of thermodynamics • Friction – causes E loss as heat
Efficiency actual amt of E that does work amt of E supplied • Furnace: 1.5 units of energy released by burning fuel, only 1 unit actually heats house. Efficiency? • 1/1.5 = 0.67 or 67% efficient • Means, 33% lost as waste heat
Units • Energy unit = joule (1 Newton applied over 1 meter) • Use exajoules = 1018 Joules • 1 BTU (raise temp of 1lb of H2O 1F) • 1BTU = 1055 Joules • 1 Quad = 1 exajoules or 1015 BTU • US uses 100 quads annually • World uses 425 quads annually
More units • Power = E/time • joules/sec or Watts (1 joule/sec = 1 W) • kilowatt (kW) = 1,000 W • megawatt (MW) = 1,000,000 W • gigawatt (GW) = 1,000,000,000 W • 1 GW = 1,000 MW
Electricity • Expressed as kW hours • 1000 W applied for 1 hr (3,600 sec) • 1000W • 1000 joules x 3600 sec = 3,600,000 J 1 sec 1hr • So, 3,600,000J applied every hr.
Thermal efficiency • E produced by heat engines • Modern 1000MW generating plants are 30-40% efficient, meaning 60 – 70% wasted heat (twice the amount that produces electricity!!!!) • Electricity fed into a grid to distribute among power lines
Efficiency Examples • Coal Power Plant: 30% (70% lost as heat) • Incandescent Light Bulb: 5% (95% lost) • Photosynthesis: 1% (99% lost as heat) • Betw. trophic levels: 10% (90% lost) • Nuclear power: 35% (65% lost as heat)
Electrical resistivity • Power lines have a natural resistance to electric flow, so heat energy released from lines.
US • ¼ of the world’s total energy consumption with 5% of total population !
Energy from Fossil Fuels • Energy sources and uses • Exploiting crude oil • Other fossil fuels • Fossil fuels and energy security
Electrical Power Production: The Beginning Michael Faraday 1831
Generators in a Hydroelectric Plant Attached by a shaft to a turbine propelled by water.
oil-based fuels natural gas coal nuclear power transportation industrial processes space heating and cooling generation of electrical power Match Dominant Primary (Left) with Secondary (Right) Energy Sources
Exploiting Crude Oil • How fossil fuels are formed • Crude-oil reserves versus production • Declining U.S. reserves and increasing importation • Problems of growing U.S. dependency on foreign oil
Crude-Oil Reserves Versus Production • Estimated reserves: educated guesses about the location and size of oil or natural gas deposits • Proven reserves: how much oil can be economically obtained from the oil field • Production: withdrawal of oil or gas from the oil field
Algeria Indonesia Iran Iraq Kuwait Libya Nigeria Qatar Saudi Arabia United Emirates Venezuela Organization of Petroleum Exporting Countries: OPEC
Oil • US: ~20+ million barrels used per day • World: 85+ million barrels per day • 850 BB of proven reserves left • 700+/- BB unknown reserves??? • Run out in +/- 40 years • OPEC dominates oil • Increased reliance on OPEC nations http://www.worldometers.info/
Algeria Indonesia Iran Iraq Kuwait Libya Nigeria Qatar Saudi Arabia United Emirates Venezuela Organization of Petroleum Exporting Countries: OPEC
Problems from Foreign Oil Dependency • Variations in cost of purchases • Threat of supply disruptions • Limitations of nonrenewable resource
Impacts of Foreign Oil Dependence • Trade imbalances • Military actions • Pollution of oceans • Coastal oil spills
Oil History • 70’s Oil Crisis: OPEC banned Israel supporting nations (US) • Persian Gulf War: 1990, Saddam Hussein attacked Kuwait to control oil 6MB/day, US maintained control…upset Al Qaeda • 9/11/01: 2003 War - Blood for Oil?
Keystone Pipeline • 700,000 barrels per day capacity.
Today’s prices 1 barrel crude oil = 42 gallons = 19 gallons of gas after processing http://www.oil-price.net/
Cost of Gasoline • Cost of crude oil is about 48% of the price. • Federal and state taxes make up about 23% of the price. • Refining costs and margins is about 18% of the price. • And all other distribution and marketing costs are about 12% of the price. This includes transportation, storage, credit card fees (typically 2 to 4 percent), cost of doing business, sales taxes, and the retailer's gross margin.
Trans Alaskan Pipeline • Built 1974-1977 because of oil crisis • 16 billion barrels of oil shipped from opening until 2010 • 97% oil from North Slope • ~38 billion barrels in reserves
1960: Eisenhower made the Arctic National Wildlife Refuge (ANWR) • Bush Admin pushing to open ANWR for oil drilling • Pros: thousands of jobs, profit for oil industry • Cons:4% of daily oil consumption, wildlife
Alaskan National Wildlife Refuge • ~5.7-16 BB estimated reserves • Political battle to use oil here • Tundra: permafrost • Thin/delicate soil layer • Slow recovery for growth • Cold: slow decomposition (oil spill???)
Pipeline/drilling consequences: • Displace populations • Disrupt migration (Caribou) • Etc. • Benefits: • Electric production, lubricants, fuel, plastics, heating, fuel, synth. rubber pesticides, etc.
Other Fossil Fuels • Natural gas – ~92 -year supply • Coal – 225-year supply • Oil shales and oil sands - complex extraction technologies