FOSSIL FUELS

1. CH. 10 FOSSIL FUELS CHAPTER 10

2. political and environmental issue • OPEC – largely Arab countries – Organization of Petroleum Exporting Countries • 1973 restricted import into US. – ahhhhh!!!! • Strategic Petroleum Reserve – prevent crisis during f.f. interruption – 1 billion barrels

3. 1970s – US conserved – drove less, bought fewer cars, used less heat/air • 1980s – oil prices low and consumption is high • 1990s – continued foreign dependence • Current – more non OPEC suppliers, cheap energy, HIGH US consumption – large vehicles, larger energy-sucking homes (high ceilings, central air, hot tubs, etc.), increased speed limits from 55 mph • 55% US oil imported • Supplies won’t last forever

4. HDC v. LDC • 20% of population using 60% of energy • 1 person in HDC = 8 in LDC • Ex: agriculture – tractors v. animals in field, energy to make fertilizers and pesticides • To raise LDC standard of living usually includes a rise in per capita energy consumption • Energy in US: 42% industries (making chemicals, minerals, food); 33% make buildings comfortable (heat/air, lights, hot water); 25% transportation

5. Fossil fuels • Coal, oil, natural gas • Partially decayed remnants of organism • Supplies most of energy in N. America • Other sources: nuclear, solar, wind, etc. • Nonrenewable resource – forming, but too slowly

6. Fossil fuel formation • Ancient climate: warm with many swamps with big trees • Plant die, don’t decompose well in watery grave – no fungi in oxygen deprived env., anaerobic bacteria don’t decay wood quickly • Sea level changes, sediment traps plants • TIME, heat, pressure  convert nondecomposedplant material into carbon rich coal. • Oil: microscopic aquatic organism died and decompose in sediment and create oxygen deprived env.  no more decomposition. Sediment covered. • Natural gas (mainly methane): similar formation as oil, but hotter • Oil/natural gas are less dense than rock – tend to move up through porous rock and accumulate beneath nonporous rock

7. COAL • Industrial Revolution of mid 18th century • Mainly for electricity; other: energy to melt iron during conversion to steel • Different grades – higher heat during formation = drier, harder, higher energy content

8. Grades of Coal Little heat/soft Lots of heat/hard • Lignite – soft, little heat, little sulfur; lots in W. US • Subbituminous – little heat and little sulfur, lots in Alaska • Bituminous (“soft coal”) – most common, sulfur!, lots of heat, lots in Appalachian region • Anthracite (“hard coal”) least sulfur, highest heat, mostly depleted in US

9. COAL RESERVES • Most abundant ff • China, US (25%), Russia, etc. • Last 200 years at present rate, more if deeper deposits become available

10. SAFETY PROBLEMS WITH COAL • Subsurface mining dangerous for miners (cave-ins) • Increased risk of cancer and black lung disease

11. ENVIRONMENTAL IMPACTS OF MINING • Surface Mining Control and Reclamation Act (SMCRA) – 1977: requires reclamation of surface coal mines • Reshape land, spread topsoil, plant seeds/plants, sedimentation ponds confine sediment filled water, prevent acid mine drainage (rains through iron sulfide minerals and carries sulfuric acid to lakes/streams) QUICK SUMMARY: Water pollution: sediment and acid Land destruction: removes topsoil/can’t grow plants/erosion/habitat loss

12. ENVIRONMENAL IMPACTS WITH BURNING COAL • Releases CO2 – prevents heat from leaving planet • Possible effects: melt polar ice  raise sea levels and flood coastal areas, increases coastal erosion and increase risk of violent storms • Most CO2 per unit heat • Most air pollution • Mercury – 1/3 of all airborne emissions (biomagnification!!! Consuming large fish…ick) • NOx and SOx from bituminous coal + H2O  acid deposition • Normal rain = ph 5.6 • Effects: decrease aquatic animal populations, damage forests

13. MAKING COAL CLEANER 1. Scrubbers – remove sulfur. Chemical react with sulfur to create precipitate to settle out; expensive – 10%-15% of construction costs 2. Lime scrubbers – H2O + lime sprayed to neutralize sulfur dioxide – creates calcium sulfate sludge. Landfills • Resource recovery: • sell calcium sulfate (synthetic gypsum) to make drywall, to farmers for soil (hold water) • Fly ash is used to make lightweight concrete 3. Electrostatic precipitator – removes particulate matter (like fly ash) 4. fluidized-bed combustion – mixes crushed coal with limestone during combustion. Limestone neutralizes sulfur-dioxide  calcium sulfate. Lower temperature produces less Nox • Produces more heat from a given amount of coal, less CO2 emitted per unit electricity

15. Can coal ever be truly clean? • What does that mean anyway? • “Clean coal”

16. Clean Air Actprotects the public from air pollutants hazardous to our health Amendments of 1990: Reduce emissions of sulfur dioxide and nitrogen oxides to reduce acid rain

17. OIL AND NATURAL GAS • Most of energy used in world (including US) • Petroleum = crude oil • Petrochemical: plastics, fertilizers, pesticides • Natural gas: mainly methane, some butane, propane. • +: very little air pollutants • -: difficult to transport b/c a gas • Methane – generate electricity, transportation • Store butane, propane as liquid (liquified petroleum gas)

19. EXTRACTION • Oil pumps • Find traps by: • Drill test holes to obtain rock samples • Produce explosion and analyze sound waves • $$

20. “Fracking” – hydraulic fracturing • Water, sand, and chemicals injecting underground to release natural gas • Concerns: contaminating groundwater with unknown chemicals and methane

21. RESERVES • Oil: middle east – over 50%/ ~ 50 years left (not considering industrialization of China) • Natural gas – Russia (40%) and Iran/ ~ 150 years

22. Environmental problems with natural gas and oil • 1. burning the fuel – CO2 (less with natural gas), acid deposition (not natural gas) • 2. production and transport – • Exxon Valdez Alaskan Oil Spill 1989: lack of double hull; hit reef; killed birds, sea otters, etc. • Persian Gulf Oil Spill – biggest in world, on purpose, 6 million barrels • Deepwater Horizon (BP) oil spill - during deep water drilling – 5 million barrels

23. Arctic National Wildlife Refuge (ANWR) • Debate to open to oil exploration • + create jobs, area close by production declining, decrease dependence of foreign oil • - hurt national wildlife refuge (platforms, pipelines, roads, potential spills), temporary amount will increase future dependence

24. SYNFUELS – another option for the future • Liquid/gas from coal or other natural sources • Drawbacks – energy intensive to produce = low net energy yield • Types: • Methane Hydrates – methane in ice (permafrost areas, beneath deep ocean floor); positive feedback (global warming) • Tar sands – have bitumen (semi-solid oil), can convert bitumen to oil, mined using strip-mining • Oil Shale – “oily rock” • Coal-to-liquid • Easy to transport through pipes, produce gasoline, can use lower grade coal, $$, requires energy

25. Keystone XL pipeline • Oil sands (tar sands) in Canada • Concerns : • Oil spills/crossing Ogallala Aquifer • Extracting: surface mining or injecting lots of steam to make less thick = lots of energy (=lots of CO2)/ Boreal forest • Expensive to turn into gasoline

26. Pros/cons summary • Coal +: plentiful, not harmful if spilled, relative high energy yield -: erosion, acid mine drainage, hurts miners, NOx/SOx/CO2/mercury • Oil +: cheap, versatile, high energy yield - : NOx/SOx, CO2, , oil spills, wildlife habitats • Natural gas +: no pollution from NOx and SOx, high energy yield -: highly explosive, hard to transport (pipes carry risk of leaks/explosions), methane (CH4 is a greenhouse gas and ozone destroyer), least amount CO2