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CH. 10
CHAPTER 10
political and environmental issue OPEC – largely Arab countries –
Organization of Petroleum Exporting Countries1973 restricted import into US. – ahhhhh!!!!Strategic Petroleum Reserve – prevent crisis
during f.f. interruption – 1 billion barrels
• 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
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
Fossil fuels Coal, oil, natural gas Partially decayed
remnants of organism Supplies most of
energy in N. AmericaOther sources: nuclear,
solar, wind, etc.
Nonrenewable resource – forming, but too slowly
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 nondecomposed
plant 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
COALCOAL 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
Grades of Coal
1. Lignite – soft, little heat, little sulfur; lots in W. US
2. Subbituminous – little heat and little sulfur, lots in Alaska
3. Bituminous (“soft coal”) – most common, sulfur!, lots of heat, lots in Appalachian region
4. Anthracite (“hard coal”) least sulfur, highest heat, mostly depleted in US
Little heat/soft
Lots of heat/hard
COAL RESERVES Most abundant ff China, US (25%),
Russia, etc. Last 200 years at
present rate, more if deeper deposits become available
SAFETY PROBLEMS WITH COAL Subsurface mining dangerous for miners
(cave-ins) Increased risk of cancer and black lung
disease
ENVIRONMENTAL IMPACTS OF MINING
Surface Mining Control and Reclamation Act (SMCRA) – 1977: requires reclamation of surface coal minesReshape 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
ENVIRONMENAL IMPACTS WITH BURNING COAL
Releases CO2 – prevents heat from leaving planetPossible 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
MAKING COAL CLEANER1. 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
Can coalcoal ever be truly clean? What does that mean anyway?
“Clean coal”
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
OIL AND NATURAL GASOIL 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 gasMethane – generate electricity, transportationStore butane, propane as liquid (liquified petroleum gas)
EXTRACTION Oil pumps
Find traps by:Drill test holes to obtain rock samplesProduce explosion and analyze sound waves$$
“Fracking” – hydraulic fracturing Water, sand, and chemicals injecting
underground to release natural gasConcerns: contaminating groundwater with
unknown chemicals and methane
RESERVES Oil: middle east – over 50%/ ~ 50 years
left (not considering industrialization of China)
Natural gas – Russia (40%) and Iran/ ~ 150 years
Environmental problems with natural gas and oil 1. burning the fuel – CO2 (less with natural gas),
acid deposition (not natural gas)
2. production and transport – Exxon Valdez Alaskan Oil Spill 1989: lack of
double hull; hit reef; killed birds, sea otters, etc.Persian Gulf Oil Spill – biggest in world, on purpose,
6 million barrelsDeepwater Horizon (BP) oil spill - during deep water
drilling – 5 million barrels
Arctic National Wildlife Refuge (ANWR) Debate to open to oil exploration + create jobs, area close by production declining,
decrease dependence of foreign oil
- hurt national wildlife refuge (platforms, pipelines, roads, potential spills), temporary amount will increase future dependence
SYNFUELS – another option for the future Liquid/gas from coal or other natural sources Drawbacks – energy intensive to produce = low net energy yield Types:
Methane Hydrates – methane in ice (permafrost areas, beneath deep ocean floor); positive feedback (global warming)
Tar sands – have bitumen (semi-solid oil), can convert bitumen to oil, mined using strip-mining
Oil Shale – “oily rock” Coal-to-liquid
○ Easy to transport through pipes, produce gasoline, can use lower grade coal, $$, requires energy
Keystone XL pipeline
Oil sands (tar sands) in Canada Concerns :
Oil spills/crossing Ogallala AquiferExtracting: surface mining or injecting lots of
steam to make less thick = lots of energy (=lots of CO2)/ Boreal forest
Expensive to turn into gasoline
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